Mifsud SA, etal., J Am Soc Nephrol. 2002 Mar;13(3):684-92.
It was previously reported that transgenic (mRen-2)27 rats with streptozotocin-induced diabetes mellitus progressively develop advanced nephropathy in 12 wk. These lesions are largely prevented when the angiotensin-converting enzyme inhibitor perindopril is administered from the time of induction of
diabetes mellitus. This study aimed to determine the lowest dose of early perindopril treatment required for substantial improvement of renal function and structure and to investigate whether late intervention prevents or reverses the progression of established renal lesions. At 6 wk of age, female heterozygous Ren-2 rats were randomized to receive either streptozotocin (diabetic) or citrate buffer (control). Rats were gavaged, beginning early after the induction of diabetes mellitus or the administration of control vehicle, with 0, 0.02, 0.2, or 2 mg/kg per d perindopril for 12 wk. A separate group of diabetic Ren-2 rats received late treatment with 2 mg/kg per d perindopril throughout week 8 to week 12, when rats were hypertensive and albuminuric and exhibited increased kidney weight and glomerulosclerotic index (GSI). Among diabetic rats, early 0.02 mg/kg per d perindopril treatment reduced systolic BP, GSI, and renal collagen staining but had no effect on albuminuria or kidney hypertrophy. Early 0.2 or 2 mg/kg per d perindopril treatment further reduced systolic BP, GSI, and renal collagen staining and decreased albuminuria and kidney hypertrophy. Late intervention was as antihypertensive and antialbuminuric as early 0.2 or 2 mg/kg per d perindopril treatment but did not prevent a moderate increase in GSI. In conclusion, early treatment with 0.2 mg/kg per d perindopril was the lowest dosage to largely prevent severe diabetic nephropathy in transgenic Ren-2 rats. Late-onset perindopril treatment of diabetic rats with established nephropathy was as efficacious as early treatment with respect to various renal parameters, such as albuminuria, but was associated with moderate progression of glomerulosclerosis.
Mifune Y, etal., Osteoarthritis Cartilage. 2013 Jan;21(1):175-85. doi: 10.1016/j.joca.2012.09.018. Epub 2012 Oct 4.
OBJECTIVE: Platelet-rich plasma (PRP) is reported to promote collagen synthesis and cell proliferation as well as enhance cartilage repair. Our previous study revealed that the intracapsular injection of muscle derived stem cells (MDSCs) expressing bone morphogenetic protein 4 (BMP-4) combined with
soluble Flt-1 (sFlt1) was effective for repairing articular cartilage (AC) after osteoarthritis (OA) induction. The current study was undertaken to investigate whether PRP could further enhance the therapeutic effect of MDSC therapy for the OA treatment. METHODS: MDSCs expressing BMP-4 and sFlt1 were mixed with PRP and injected into the knees of immunodeficient rats with chemically induced OA. Histological assessments were performed 4 and 12 weeks after cell transplantation. Moreover, to elucidate the repair mechanisms, we performed in vitro assays to assess cell proliferation, adhesion, migration and mixed pellet co-culture of MDSCs and OA chondrocytes. RESULTS: The addition of PRP to MDSCs expressing BMP-4 and sFlt1 significantly improved AC repair histologically at week 4 compared to MDSCs expressing BMP-4 and sFlt1 alone. Higher numbers of cells producing type II collagen and lower levels of chondrocyte apoptosis were observed by MDSCs expressing BMP-4 and sFlt1 and mixed with PRP. In the in vitro experiments, the addition of PRP promoted proliferation, adhesion and migration of the MDSCs. During chondrogenic pellet culture, PRP tended to increase the number of type II collagen producing cells and in contrast to the in vivo data, it increased cell apoptosis. CONCLUSIONS: Our findings indicate that PRP can promote the therapeutic potential of MDSCs expressing BMP-4 and sFlt1 for AC repair (4 weeks post-treatment) by promoting collagen synthesis, suppressing chondrocyte apoptosis and finally by enhancing the integration of the transplanted cells in the repair process.
In the present study, effects of voluntary exercise in an obese animal model were investigated in relation to the rhythm of daily activity and ghrelin production. Male Sprague-Dawley rats were fed either a high fat diet (HFD) or a chow diet (CD) from four to 16 weeks old. They were further subdivid
ed into either an exercise group (HFD-Ex, CD-Ex) with a running wheel for three days of every other week or sedentary group (HFD-Se, CD-Se). At 16 weeks old, marked increases in body weight and visceral fat were observed in the HFD-Se group, together with disrupted rhythms of feeding and locomotor activity. The induction of voluntary exercise brought about an effective reduction of weight and fat, and ameliorated abnormal rhythms of activity and feeding in the HFD-Ex rats. Wheel counts as voluntary exercise was greater in HFD-Ex rats than those in CD-Ex rats. The HFD-obese had exhibited a deterioration of ghrelin production, which was restored by the induction of voluntary exercise. These findings demonstrated that abnormal rhythms of feeding and locomotor activity in HFD-obese rats were restored by infrequent voluntary exercise with a concomitant amelioration of the ghrelin production and weight reduction. Because ghrelin is related to food anticipatory activity, it is plausible that ghrelin participates in the circadian rhythm of daily activity including eating behavior. A beneficial effect of voluntary exercise has now been confirmed in terms of the amelioration of the daily rhythms in eating behavior and physical activity in an animal model of obesity.
It remains poorly understood how the haematopoietic stem/progenitor cells (HSPC) are attracted to their niches and the functional consequences of such interaction. In the present study, we show that the cell cycle regulator cyclin A1 in association with vascular endothelial growth factor receptor 1
(VEGFR1), is required for HSPC and their niches to maintain their function and proper interaction. In the absence of cyclin A1, the HSPC in the BM are increased in their frequency and display an increased migratory and homing ability. Concomitantly, the ability of the endosteal and central BM niche zones to attract and home the wild-type HSPC is significantly reduced in cyclin A1-null mice as compared to the wild-type controls. The impaired proliferation and homing of HSPC in the BM of cyclin A1-null mice are attributed to the increased density of microvessels in the endosteal and central BM niche zones, which is associated with the increased VEGFR1 expression. Thus, modulation of cyclin A1 and VEGFR1 in HSPC and their niches may provide new insights into therapeutic approaches.
Ramayani OR, etal., J Dev Orig Health Dis. 2016 Feb;7(1):102-7. doi: 10.1017/S2040174415007850. Epub 2015 Nov 6.
There is no satisfactory explanation as to why some nephrotic syndrome (NS) patients respond to glucocorticoids and others do not. The aim of this study was to investigate an association between single nucleotide polymorphism of the MIF gene -rs755622 and serum
MIF concentrations in NS patients. During a period between November 2011 and September 2012, 120 consecutive children divided into three groups [healthy children, steroid-resistant nephrotic syndrome (SRNS) and steroid-sensitive nephrotic syndrome (SSNS)] were examined. Children were defined as healthy when they had a normal estimated glomerular filtration rate and spot urinary albumin creatinine ratio <150 mug/mg creatinine. SRNS was diagnosed in children who did not respond to the usual doses of steroids within 4 weeks of initiating treatment. SSNS patients were defined as those who had remission after usual doses of steroids. The genotype of -173 G to C polymorphism of the MIF gene was determined using polymerase chain reaction restriction fragment length polymorphism methods. Serum MIF concentration was measured using sandwich enzyme-linked immunosorbent assay. The allele frequency of the C allele was higher in SRNS compared with that of SSNS patients (P=0.025). There was a trend toward an association between genotypes and serum MIF disturbances. In conclusion, this study noted elevated circulating serum MIF levels and higher frequency of the C allele of the MIF gene in SRNS patients. The presence of the C allele implies an increased risk for steroid resistance.
The objective of the study was to determine whether plasma migration inhibitor factor (MIF) concentration and mononuclear cell (MNC) mRNA are elevated in obesity and whether treatment with metformin reduces plasma MIF concen
tration.Forty obese subjects [body mass index (BMI), 37.5 +/- 4.9 kg/m(2)] and 40 nonobese healthy subjects (BMI, 22.6 +/- 3.4 kg/m(2)) had their plasma MIF, glucose, insulin, free fatty acids (FFAs) and C-reactive protein (CRP) concentrations measured. Sixteen obese patients and 16 nonobese healthy subjects had RNA prepared from MNCs. Eight obese subjects with normal glucose concentration were treated with metformin 1 g (Glucophage XR; 1000 mg twice daily) twice daily for 6 wk. Eight obese subjects were used as controls. Plasma concentration of glucose, insulin, FFAs, and MIF was measured by appropriate assays. mRNA for MIF was measured by real-time PCR.Forty obese subjects had a fasting concentration of MIF of 2.8 +/- 2.0 ng/ml, whereas 40 nonobese subjects had a fasting MIF concentration of 1.2 +/- 0.6 ng/ml (P < 0.001). Plasma MIF concentrations were significantly related to BMI (r = 0.52; P < 0.001). mRNA for MIF was correlated to plasma FFAs (r = 0.40; P < 0.05) and plasma CRP (r = 0.42; P < 0.05) concentrations. Eight obese subjects had their fasting blood samples taken before and after taking a slow-release preparation of metformin at 1, 2, 4, and 6 wk. The mean plasma concentration fell from 2.3 +/- 1.4 to 1.6 +/- 1.2 ng/ml at 6 wk (P < 0.05). Obese subjects not on treatment with metformin showed no change. During the period of treatment with metformin, the body weight did not change and the plasma concentration of glucose, insulin, and FFAs did not alter.We conclude that: 1) plasma MIF concentrations and MIF mRNA expression in the MNCs are elevated in the obese, consistent with a proinflammatory state in obesity; 2) these increases in MIF are related to BMI, FFA concentrations, and CRP; 3) metformin suppresses plasma MIF concentrations in the obese, suggestive of an antiinflammatory effect of this drug; and 4) this action of metformin may contribute to a potential antiatherogenic effect, which may have implications for the reduced cardiovascular mortality observed with metformin therapy in type 2 diabetes mellitus.
The function of macrophage migration inhibitory factor (MIF) in sperm maturation was studied by investigating its role in the biochemical maturation of the outer dense fibres. Rat sperm obtained from the caput and cauda epididymis were stimulated overnight with
either recombinant MIF or MIF-containing vesicles originating from epididymal fluid at various concentrations. The zinc content of both the sperm and the medium was determined by means of atomic absorption spectrometry. Incubation in both recombinant MIF and vesicular MIF resulted in a statistically significant decrease of the zinc content in stimulated caput sperm of approximately 50%. In parallel, the conditioned media showed a clear increase in the concentration of this trace metal. The effect of MIF was less marked in cauda sperm. In addition, we demonstrated a statistically significant increase of detectable free thiol groups in the sperm mid- and principle piece in isolated rat sperm after stimulation with MIF at concentrations of 25 and 50 ng/ml. Our data suggest that MIF plays an important role in the maturation process of rat sperm during epididymal transit by inducing the elimination of zinc and affecting the amount of free sulphydryl groups in the sperm flagella.
Macrophage migration inhibitory factor (MIF) is a potent pro-inflammatory cytokine that also counter-regulates glucocorticoid action. We investigated whether immunoneutralization of MIF could reverse established experimental
crescentic glomerulonephritis and if this treatment could modulate endogenous glucocorticoid levels. Accelerated anti-GBM glomerulonephritis was induced in six littermate pairs of rats. Once crescentic disease was established on day 7, one animal in each pair was given a daily injection of neutralizing anti-MIF antibody (Ab) or irrelevant isotype control Ab for 14 days and then killed on day 21. In addition, a group of 6 animals was killed on day 7 of disease without any treatment. Animals receiving the control Ab exhibited a rapidly progressive glomerulonephritis with severe renal injury (proteinuria), loss of renal function (creatinine clearance), anemia, and marked histologic damage (including glomerular crescent formation), compared with animals killed on day 7 without treatment. In contrast, anti-MIF Ab treatment partially reversed the disease by restoring normal renal function and reducing histological damage compared with untreated animals killed on day 7 (p < 0.05). Interestingly, anti-MIF Ab treatment also prevented severe anemia (p < 0.05). Reversal of disease was associated with a significant reduction in leukocyte infiltration and activation and renal interleukin-1 (IL-1) production. Importantly, anti-MIF Ab treatment caused a significant increase in endogenous serum corticosterone levels, which correlated with the reversal of disease parameters. In conclusion, this study has demonstrated that blocking MIF activity can partially reverse established crescentic glomerulonephritis and suggests that MIF operates by both enhancing the cellular immune response and suppressing the endogenous anti-inflammatory glucocorticoid response.
Vera PL, etal., Exp Biol Med (Maywood). 2008 May;233(5):620-6. Epub 2008 Mar 28.
The objective of this study was to determine if macrophage migration inhibitory factor (MIF) is upregulated in the bladder during persistent cystitis. MIF is a pro-inflammatory cytokine found pre-formed in the urothelium. Pr
evious findings showed that acute bladder inflammation increased MIF release into the bladder lumen while upregulating MIF and CD74 (MIF receptor) in the bladder. Because the effects of persistent cystitis on MIF and CD74 are not known, MIF and CD74 changes in the bladder were examined after short-term (1-day) or persistent (8-day) cyclophosphamide (CYP)-induced bladder inflammation. Anesthetized male Sprague-Dawley rats received either a single CYP treatment (150 mg/kg, ip; saline, control) and examined 1 day after treatment (short-term), or repeated CYP doses (20-75 mg/ kg, ip; saline, control; every third day for 8 days) and examined after 8 days of treatment (persistent). MIF protein levels in urine and bladder were determined. In addition, Mif, CD74, and cox-2 expression in the bladder was determined. Histology verified cystitis and MIF and CD74 immunoreactivity in the bladder. Repeated CYP doses were decreased to avoid toxicity. Short-term or repeated low CYP doses (40 mg/kg; 8 days) increased urinary MIF and decreased bladder MIF amounts while upregulating bladder Mif and CD74 mRNA expression. Persistent CYP-induced bladder inflammation (even at 40 mg/kg; 8-day treatment) also upregulated other inflammatory cytokines (CCL5, IL-11, iNOS) in the bladder. Short-term and persistent (low dose) CYP cystitis are associated with markedly increased MIF release into the urine and upregulation of Mif and CD74 in bladder. This supports the hypothesis that MIF and CD74 play a significant role in both acute and persistent stages of bladder inflammation.
Majewski IJ, etal., Proc Natl Acad Sci U S A. 2006 Sep 19;103(38):14146-51. Epub 2006 Sep 11.
We have generated mice from a N-ethyl-N-nitrosourea mutagenesis screen that carry a mutation in the translation initiation codon of Gata-1, termed Plt13, which is equivalent to mutations found in patients with acute megakaryoblastic leukemia and Down syndrome. The Gata-1 locus is present on the X c
hromosome in humans and in mice. Male mice hemizygous for the mutation (Gata-1Plt13/Y) failed to produce red blood cells and died during embryogenesis at a similar stage to Gata-1-null animals. Female mice that carry the Plt13 mutation are mosaic because of random inactivation of the X chromosome. Adult Gata-1Plt13/+ females were not anemic, but they were thrombocytopenic and accumulated abnormal megakaryocytes without a concomitant increase in megakaryocyte progenitor cells. Gata-1Plt13/+ mice contained large numbers of blast-like colony-forming cells, particularly in the fetal liver, but also in adult spleen and bone marrow, from which continuous mast cells lines were readily derived. Although the equivalent mutation to Gata-1Plt13 in humans results in production of GATA-1s, a short protein isoform initiated from a start codon downstream of the mutated initiation codon, Gata-1s was not detected in Gata-1Plt13/+ mice.
Kennedy CLM, etal., Neurobiol Stress. 2023 Mar 7;23:100532. doi: 10.1016/j.ynstr.2023.100532. eCollection 2023 Mar.
Hippocampal mineralocorticoid receptors (MRs) and glucocorticoid receptors (GRs) mediate glucocorticoid hormone (GC) action in the hippocampus. These receptors bind to glucocorticoid responsive elements (GREs) within target genes, eliciting transcriptional effects in response to stress and circadian
variation. Until recently, little was known about the genome-wide targets of hippocampal MRs and GRs under physiological conditions. Following on from our genome-wide MR and GR ChIP-seq and Ribo-Zero RNA-seq studies on rat hippocampus, we investigated the Krüppel-like factors (KLFs) as targets of MRs and GRs throughout the brain under circadian variation and after acute stress. In particular, Klf2, Klf9 and Klf15 are known to be stress and/or GC responsive and play a role in neurobiological processes including synaptic plasticity and neuronal differentiation. We found increased binding of MR and GR to GREs within Klf2, Klf9 and Klf15 in the hippocampus, amygdala, prefrontal cortex, and neocortex after acute stress and resulting from circadian variation, which was accompanied by upregulation of corresponding hnRNA and mRNA levels. Adrenalectomy abolished transcriptional upregulation of specific Klf genes. These results show that MRs and GRs regulate Klf gene expression throughout the brain following exposure to acute stress or in response to circadian variation, likely alongside other transcription factors.
Kuroda M, etal., J Gastroenterol Hepatol. 2004 Feb;19(2):146-53.
BACKGROUND AND AIM: Eisai hyperbilirubinuria rats (EHBR) are animal models of Dubin-Johnson syndrome, which suffer from jaundice due to impaired biliary excretion of bilirubin glucuronides. In EHBR, deficiency of multidrug resistance-associated protein 2 (mrp2) causes defective biliary excretion of
numerous organic anions. However, little is known about the expression of other organic anion transporters in this mrp2-deficient model. The aim of the present study was to investigate adaptive expressions of mrp1, mrp3, mrp6, organic anion transporting polypeptide 1 (oatp1) and oatp2 in liver and kidney of EHBR. METHODS: For the present study, EHBR (n = 5) were used. Hepatic and renal mRNA expression of the aforementioned transporters was determined by constructed semiquantitative reverse transcription polymerase chain reaction assay. Their protein expression was determined by western blotting. Localization of hepatic and renal mrp3 was confirmed by immunohistochemistry. Sprague-Dawley (SD) rats (n = 5) were used as normal controls. RESULTS: Deficiency of mrp2 protein was confirmed in EHBR. Hepatic and renal expression of mrp3 mRNA was 53.6% (P < 0.001) and 82.9% (P < 0.001), and its protein expression was 298.9% (P < 0.001) and 245.0% (P = 0.001) higher in EHBR than in SD rats, respectively. Hepatic and renal expression of mrp1 and mrp6 mRNA was not significantly different between EHBR and SD rats. The mrp1 and mrp6 proteins were expressed in very low amounts in the liver and kidney of both EHBR and SD rats. In contrast to mrp3, hepatic expression of oatp1 and oatp2 mRNA was 33.9% (P = 0. 001) and 38.6% (P < 0.001), and their protein expression was 57.4% (P < 0.05) and 51.0% (P < 0.01) lower in EHBR than in SD rats, respectively. Hepatic and renal mrp3 protein was localized at the basolateral membrane. CONCLUSIONS: Mrp3 plays an important role in the compensation of mrp2 deficiency in liver and kidney of EHBR. Hepatic expressions of mrp3, oatp1 and oatp2 changed adaptively in this animal model. This is a compensatory mechanism for reducing injury to hepatocytes from cytotoxic materials that increase in mrp2 deficiency.
DNA damage is a cause of age related pathologies, including osteoarthritis (OA). Excision repair cross complementation group 1 (ERCC1) is an endonuclease required for DNA damage repair. In this study we investigated the function of ERCC1 in chondrocytes and its association with the pathophysiology
of OA. ERCC1 expression in normal and osteoarthritic cartilage was assessed, as were changes in ERCC1 expression in chondrocytes under catabolic stress. Inhibiting ERCC1 in chondrocytes under interleukin-1beta stimulation using small interfering RNA (siRNA) was also evaluated. Finally, cellular senescence and apoptosis were examined in relation to ERCC1 function. ERCC1 expression was decreased in OA cartilage and increased within 4 h of exposure to interleukin (IL)-1beta, but decreased after 12 h. The inhibition of ERCC1 by siRNA increased the expression of matrix metallopeptidase 13 and decreased collagen type II. ERCC1 inhibition also increased the number of apoptotic and senescent cells. The inhibition of ERCC1 in chondrocytes increased their expression of OA related proteins, apoptosis, cellular senescence, and hypertrophic-like changes which suggest that ERCC1 is critical for protecting human chondrocytes (HCs) from catabolic stresses and provides insights into the pathophysiology of OA and a potential target for its treatment. (191)
Reactive oxygen species are involved in the mitogenic signal transduction cascades initiated by several growth factors and play a critical role in mediating cardiovascular diseases. Interestingly, H(2)O(2) induces tyrosine phosphorylation and trans-activation of the platelet-derived growth factor re
ceptor and the epidermal growth factor receptor in many cell lines including vascular smooth muscle cells. To investigate the molecular mechanism by which reactive oxygen species contribute to vascular diseases, we have examined a signal transduction cascade involved in H(2)O(2)-induced platelet-derived growth factor receptor activation in vascular smooth muscle cells. We found that H(2)O(2) induced a ligand-independent phosphorylation of the platelet-derived growth factor-beta receptor at Tyr(1021), a phospholipase C-gamma binding site, involving the requirement of protein kinase C-delta and c-Src that is distinct from a ligand-dependent autophosphorylation. Also, H(2)O(2) induced the association of protein kinase C-delta with the platelet-derived growth factor-beta receptor and c-Src in vascular smooth muscle cells. These findings will provide new mechanistic insights by which enhanced reactive oxygen species production in vascular smooth muscle cells induces unique alleys of signal transduction distinct from those induced by endogenous ligands leading to an abnormal vascular remodeling process.
The Polycomb repressive complexes PRC1 and PRC2 maintain embryonic stem cell (ESC) pluripotency by silencing lineage-specifying developmental regulator genes. Emerging evidence suggests that Polycomb complexes act through controlling spatial genome organization. We show that PRC1 functions as a mast
er regulator of mouse ESC genome architecture by organizing genes in three-dimensional interaction networks. The strongest spatial network is composed of the four Hox gene clusters and early developmental transcription factor genes, the majority of which contact poised enhancers. Removal of Polycomb repression leads to disruption of promoter-promoter contacts in the Hox gene network. In contrast, promoter-enhancer contacts are maintained in the absence of Polycomb repression, with accompanying widespread acquisition of active chromatin signatures at network enhancers and pronounced transcriptional upregulation of network genes. Thus, PRC1 physically constrains developmental transcription factor genes and their enhancers in a silenced but poised spatial network. We propose that the selective release of genes from this spatial network underlies cell fate specification during early embryonic development.
Balogh E, etal., Proc Natl Acad Sci U S A. 2020 Jun 30;117(26):15137-15147. doi: 10.1073/pnas.2002328117. Epub 2020 Jun 17.
RNA modifications play a fundamental role in cellular function. Pseudouridylation, the most abundant RNA modification, is catalyzed by the H/ACA small ribonucleoprotein (snoRNP) complex that shares four core proteins, dyskerin (DKC1), NOP10, NHP2, and GAR1. Mutations in DKC1, NOP10, or NHP2 cause dy
skeratosis congenita (DC), a disorder characterized by telomere attrition. Here, we report a phenotype comprising nephrotic syndrome, cataracts, sensorineural deafness, enterocolitis, and early lethality in two pedigrees: males with DKC1 p.Glu206Lys and two children with homozygous NOP10 p.Thr16Met. Females with heterozygous DKC1 p.Glu206Lys developed cataracts and sensorineural deafness, but nephrotic syndrome in only one case of skewed X-inactivation. We found telomere attrition in both pedigrees, but no mucocutaneous abnormalities suggestive of DC. Both mutations fall at the dyskerin-NOP10 binding interface in a region distinct from those implicated in DC, impair the dyskerin-NOP10 interaction, and disrupt the catalytic pseudouridylation site. Accordingly, we found reduced pseudouridine levels in the ribosomal RNA (rRNA) of the patients. Zebrafish dkc1 mutants recapitulate the human phenotype and show reduced 18S pseudouridylation, ribosomal dysregulation, and a cell-cycle defect in the absence of telomere attrition. We therefore propose that this human disorder is the consequence of defective snoRNP pseudouridylation and ribosomal dysfunction.
Dakic A, etal., J Exp Med 2005 May 2;201(9):1487-502.
Although the transcription factor PU.1 is essential for fetal lymphomyelopoiesis, we unexpectedly found that elimination of the gene in adult mice allowed disturbed hematopoiesis, dominated by granulocyte production. Impaired production of lymphocytes was evident in PU.1-deficient bone marrow (BM),
but myelocytes and clonogenic granulocytic progenitors that are responsive to granulocyte colony-stimulating factor or interleukin-3 increased dramatically. No identifiable common lymphoid or myeloid progenitor populations were discernable by flow cytometry; however, clonogenic assays suggested an overall increased frequency of blast colony-forming cells and BM chimeras revealed existence of long-term self-renewing PU.1-deficient cells that required PU.1 for lymphoid, but not granulocyte, generation. PU.1 deletion in granulocyte-macrophage progenitors, but not in common myeloid progenitors, resulted in excess granulocyte production; this suggested specific roles of PU.1 at different stages of myeloid development. These findings emphasize the distinct nature of adult hematopoiesis and reveal that PU.1 regulates the specification of the multipotent lymphoid and myeloid compartments and restrains, rather than promotes, granulopoiesis.
Saunderson EA, etal., Proc Natl Acad Sci U S A. 2016 Apr 26;113(17):4830-5. doi: 10.1073/pnas.1524857113. Epub 2016 Apr 12.
Stressful events evoke long-term changes in behavioral responses; however, the underlying mechanisms in the brain are not well understood. Previous work has shown that epigenetic changes and immediate-early gene (IEG) induction in stress-activated dentate gyrus (DG) granule neurons play a crucial ro
le in these behavioral responses. Here, we show that an acute stressful challenge [i.e., forced swimming (FS)] results in DNA demethylation at specific CpG (5'-cytosine-phosphate-guanine-3') sites close to the c-Fos (FBJ murine osteosarcoma viral oncogene homolog) transcriptional start site and within the gene promoter region of Egr-1 (early growth response protein 1) specifically in the DG. Administration of the (endogenous) methyl donor S-adenosyl methionine (SAM) did not affect CpG methylation and IEG gene expression at baseline. However, administration of SAM before the FS challenge resulted in an enhanced CpG methylation at the IEG loci and suppression of IEG induction specifically in the DG and an impaired behavioral immobility response 24 h later. The stressor also specifically increased the expression of the de novo DNA methyltransferase Dnmt3a [DNA (cytosine-5-)-methyltransferase 3 alpha] in this hippocampus region. Moreover, stress resulted in an increased association of Dnmt3a enzyme with the affected CpG loci within the IEG genes. No effects of SAM were observed on stress-evoked histone modifications, including H3S10p-K14ac (histone H3, phosphorylated serine 10 and acetylated lysine-14), H3K4me3 (histone H3, trimethylated lysine-4), H3K9me3 (histone H3, trimethylated lysine-9), and H3K27me3 (histone H3, trimethylated lysine-27). We conclude that the DNA methylation status of IEGs plays a crucial role in FS-induced IEG induction in DG granule neurons and associated behavioral responses. In addition, the concentration of available methyl donor, possibly in conjunction with Dnmt3a, is critical for the responsiveness of dentate neurons to environmental stimuli in terms of gene expression and behavior.
The human cytomegalovirus (CMV) immune evasion protein, UL40, shares an identical peptide sequence with that found in the leader sequence of many human leukocyte antigen (HLA)-C alleles and when complexed with HLA-E, can modulate NK cell functions via interactions with the CD94-NKG2 receptors. Howev
er the UL40-derived sequence can also be immunogenic, eliciting robust CD8+ T cell responses. In the setting of solid organ transplantation these T cells may not only be involved in antiviral immunity but also can potentially contribute to allograft rejection when the UL40 epitope is also present in allograft-encoded HLA. Here we assessed 15 bilateral lung transplant recipients for the presence of HLA-E-restricted UL40 specific T cells by tetramer staining of peripheral blood mononuclear cells (PBMC). UL40-specific T cells were observed in 7 patients post-transplant however the magnitude of the response varied significantly between patients. Moreover, unlike healthy CMV seropositive individuals, longitudinal analyses revealed that proportions of such T cells fluctuated markedly. Nine patients experienced low-grade acute cellular rejection, of which 6 also demonstrated UL40-specific T cells. Furthermore, the presence of UL40-specific CD8+ T cells in the blood was significantly associated with allograft dysfunction, which manifested as Bronchiolitis Obliterans Syndrome (BOS). Therefore, this study suggests that minor histocompatibility antigens presented by HLA-E can represent an additional risk factor following lung transplantation.
Compelling data are revealing that the CD40/CD40L system is involved in bone metabolism. Furthermore, we have previously demonstrated that polymorphisms in both genes are associated with bone phenotypes. The aim of this study is to further characterize this association and to identify the causal fun
ctional mechanism. We conducted an association study of BMD with 15 SNPs in CD40/CD40L genes in a population of 779 women. In addition, we assessed the functionality of this association through the study of the allele-dependent expression of CD40 and CD40L in peripheral blood leukocytes (PBLs) and in human osteoblasts (OBs) obtained from bone explants by qPCR and by sequencing. When an allelic imbalance (AI) was detected, studies on allele-dependent in vitro transcription rate and on CpG methylation in the gene promoter were also performed. Our results confirm the genetic association between SNP rs116535 (T>C) of CD40L gene with LS-BMD. Regarding CD40 gene, two SNPs showed nominal P-values<0.05 for FN- and LS-BMD (Z-scores), although the association was not significant after correcting for multiple testing. Homozygous TT women for SNP rs1883832 (C>T) of CD40 gene showed a trend to have lower levels of OPG (Q-value=0.059), especially when women of BMD-quartile ends were selected (P<0.05). Regarding functionality, we detected an AI for rs1883832 with the C allele the most expressed in OBs and in PBLs. Since the rs116535 of CD40L gene did not show AI, it was not further analyzed. Finally, we described a differential methylation of CpGs in the CD40 promoter among women of high in comparison to low BMD. Our results suggest that the CD40/CD40L system plays a role in regulating BMD. Effectively, our data suggest that a decreased production of OPG could be the cause of the lower BMD observed in TT women for rs1883832 of the CD40 gene and that the degree of methylation of CpGs in the CD40 promoter could contribute to the acquisition of BMD. One possibility that deserves further study is whether the degree of methylation of the CD40 gene affects the level of CD40 expression and, consequently, the level of OPG.
Park JE, etal., Am J Physiol Gastrointest Liver Physiol. 2016 May 15;310(10):G799-807. doi: 10.1152/ajpgi.00343.2015. Epub 2016 Mar 11.
Deficiency of the orphan nuclear hormone receptor small heterodimer partner (SHP, NR0B2) protects mice from diet-induced hepatic steatosis, in part, via repression of peroxisome proliferator-activated receptor (PPAR)-gamma2 (Pparg2) gene expression. Alcoholic fatty liver diseases (AFLD) share many c
ommon pathophysiological features with non-AFLD. To study the role of SHP and PPARgamma2 in AFLD, we used a strategy of chronic ethanol feeding plus a single binge ethanol feeding to challenge wild-type (WT) and SHP-null (SHP(-/-)) mice with ethanol. The ethanol feeding induced liver fat accumulation and mRNA expression of hepatic Pparg2 in WT mice, which suggests that a high level of PPARgamma2 is a common driving force for fat accumulation induced by ethanol or a high-fat diet. Interestingly, ethanol-fed SHP(-/-) mice displayed hepatic fat accumulation similar to that of ethanol-fed WT mice, even though their Pparg2 expression level remained lower. Mortality of SHP(-/-) mice after ethanol binge feeding was significantly reduced and their acetaldehyde dehydrogenase (Aldh2) mRNA level was higher than that of their WT counterparts. After an intoxicating dose of ethanol, SHP(-/-) mice exhibited faster blood ethanol clearance and earlier wake-up time than WT mice. Higher blood acetate, the end product of ethanol metabolism, and lower acetaldehyde levels were evident in the ethanol-challenged SHP(-/-) than WT mice. Ethanol-induced inflammatory responses and lipid peroxidation were also lower in SHP(-/-) mice. The current data show faster ethanol catabolism and extra fat storage through conversion of acetate to acetyl-CoA before its release into the circulation in this ethanol-feeding model in SHP(-/-) mice.
Despite the discovery and application of many parenteral (unfractionated and low-molecular-weight heparins) and oral anticoagulant vitamin K antagonist (VKA) drugs, the prevention and treatment of venous and arterial thrombotic phenomena remain major medical challenges. Furthermore, VKAs are the on
ly oral anticoagulants used during the past 60 years. The main objective of this study is to present recent data on non-vitamin K antagonist oral anticoagulants (NOACs) and to analyze their advantages and disadvantages compared with those of VKAs based on a large number of recent studies. NOACs are novel direct-acting medications that are selective for one specific coagulation factor, either thrombin (IIa) or activated factor X (Xa). Several NOACs, such as dabigatran (a direct inhibitor of FIIa) and rivaroxaban, apixaban and edoxaban (direct inhibitors of factor Xa), have been used for at least 5 years but possibly 10 years. Unlike traditional VKAs, which prevent the coagulation process by suppressing the synthesis of vitamin K-dependent factors, NOACs directly inhibit key proteases (factors IIa and Xa). The important indications of these drugs are the prevention and treatment of deep vein thrombosis and pulmonary embolisms, and the prevention of atherothrombotic events in the heart and brain of patients with acute coronary syndrome and atrial fibrillation. They are not fixed, and dose-various strengths are available. Most studies have reported that more advantages than disadvantages for NOACs when compared with VKAs, with the most important advantages of NOACs including safety issues (ie, a lower incidence of major bleeding), convenience of use, minor drug and food interactions, a wide therapeutic window, and no need for laboratory monitoring. Nonetheless, there are some conditions for which VKAs remain the drug of choice. Based on the available data, we can conclude that NOACs have greater advantages and fewer disadvantages compared with VKAs. New studies are required to further assess the efficacy of NOACs.
BACKGROUND: Urinary monocyte chemoattractant protein-1 (MCP-1) and hepcidin are potential biomarkers of renal inflammation. We examined their association with development of diabetic nephropathy (DN) lesions in normotensive normoalbuminuric subjects with type 1 diabetes (T1D) from the Renin-Angioten
sin System Study. METHODS: Biomarker concentrations were measured in baseline urine samples from 224 subjects who underwent kidney biopsies at baseline and after 5 years. Fifty-eight urine samples below the limit of quantitation (LOQ, 28.8 pg/mL) of the MCP-1 assay were assigned concentrations of LOQ/ radical2 for analysis. Relationships between ln(MCP-1/Cr) or ln(hepcidin/Cr) and morphometric variables were assessed by sex using multiple linear regression after adjustment for age, T1D duration, HbA1c, mean arterial pressure, albumin excretion rate (AER) and glomerular filtration rate (GFR). In models that examined changes in morphometric variables, the baseline morphometric value was also included. RESULTS: Baseline mean age was 24.6 years, mean duration of T1D 11.2 years, median AER 6.4 microg/min and mean iohexol GFR 129 mL/min/1.73 m(2). No associations were found between hepcidin/Cr and morphometric variables. Higher MCP-1/Cr was associated with higher interstitial fractional volume at baseline and after 5 years in women (baseline partial r = 0.244, P = 0.024; 5-year partial r = 0.299, P = 0.005), but not in men (baseline partial r = -0.049, P = 0.678; 5-year partial r = 0.026, P = 0.830). MCP-1 was not associated with glomerular lesions in either sex. CONCLUSIONS: Elevated urinary MCP-1 concentration measured before clinical findings of DN in women with T1D was associated with changes in kidney interstitial volume, suggesting that inflammatory processes may be involved in the pathogenesis of early interstitial changes in DN.
Leng L, etal., J Exp Med 2003 Jun 2;197(11):1467-76.
Macrophage migration inhibitory factor (MIF) accounts for one of the first cytokine activities to have been described, and it has emerged recently to be an important regulator of innate and adaptive immunity. MIF is an upstr
eam activator of monocytes/macrophages, and it is centrally involved in the pathogenesis of septic shock, arthritis, and other inflammatory conditions. The protein is encoded by a unique but highly conserved gene, and X-ray crystallography studies have shown MIF to define a new protein fold and structural superfamily. Although recent work has begun to illuminate the signal transduction pathways activated by MIF, the nature of its membrane receptor has not been known. Using expression cloning and functional analysis, we report herein that CD74, a Type II transmembrane protein, is a high-affinity binding protein for MIF. MIF binds to the extracellular domain of CD74, and CD74 is required for MIF-induced activation of the extracellular signal-regulated kinase-1/2 MAP kinase cascade, cell proliferation, and PGE2 production. A recombinant, soluble form of CD74 binds MIF with a dissociation constant of approximately 9 x 10-9 Kd, as defined by surface plasmon resonance (BIAcore analysis), and soluble CD74 inhibits MIF-mediated extracellular signal-regulated kinase activation in defined cell systems. These data provide a molecular basis for MIF's interaction with target cells and identify it as a natural ligand for CD74, which has been implicated previously in signaling and accessory functions for immune cell activation.
BACKGROUND Single-nucleotide polymorphisms (SNPs) located at lncRNA may affect the stability and splicing processes of mRNA formation, which result in the alteration of its interacting partners. The SNP rs755622 within exon of antisense lncRNA MIF- AS and promot
er of MIF was implicated in renal disease risk. MATERIAL AND METHODS In this case-control study, we genotyped the SNP rs755622 in 230 patients diagnosed with nephrolithiasis and 250 controls in a Chinese population. RESULTS We found that the rs755622 CG and CC genotypes had a significantly increased nephrolithiasis risk (adjusted OR=1.52, 95% CI=1.03-2.25; OR=2.63, 95% CI=1.21-5.72, P=0.015), compared with GG genotype in the additive model. The rs755622 C carriers (GC/CC) had an adjusted OR (95% CI) of 1.65 (1.14-2.39, P=0.016), compared with the GG genotype in the dominant model. This hazardous effect was more pronounced in subgroup age >46, BMI >24, hypertension, ever smoking, and ever drinking subjects. Moreover, we found that rs755622 could modulate the function of MIF-AS by influencing its folding. CONCLUSIONS These results indicate that the MIF-AS rs755622 polymorphism may have a crucial role in the development of nephrolithiasis.
BACKGROUND/AIMS: The counterbalance of macrophage migration inhibitory factor (MIF) and Gremlin-1 is a useful tool to predict the acuity of coronary artery disease (CAD) and plaque stability. Gremlin1 is an endogenous antagonist of MIF
>MIF and therefore influences plaque vulnerability. This study was designed to elucidate the mechanistic basis determining the biophysical binding of Gremlin-1 to MIF. METHODS: An in silico model suggested that several charged C-terminal amino acids are crucial in mediating Gremlin-1/MIF-binding. We produced several single amino acid exchange mutants of Gremlin-1 by site-directed mutagenesis. These Gremlin-1 mutants were tested for their ability to reduce MIF effects on monocytes. RESULTS: We observed that the critical element of the Gremlin-1 molecule for regulating MIF-induced chemotactic activity lies at the C-terminal region. A single amino acid exchange of an arginine to an alanine residue is sufficient to abolish the antagonistic effect of Gremlin-1 on MIF. Therefore, the Gremlin-1 mutant R172A failed to reduce MIF-induced monocyte differentiation into macrophages. CONCLUSION: Gremlin-1 C-terminus is essential for antagonizing MIF effects. Our results could offer a novel strategy utilizing Gremlin-1 to target pro-inflammatory effects of MIF in various diseases.
Yao J, etal., J Clin Invest. 2016 Feb;126(2):732-44. doi: 10.1172/JCI81937. Epub 2016 Jan 11.
The immunoregulatory cytokine macrophage migration inhibitory factor (MIF) is encoded in a functionally polymorphic locus that is linked to the susceptibility of autoimmune and infectious diseases. The MIF promoter contains
a 4-nucleotide microsatellite polymorphism (-794 CATT) that repeats 5 to 8 times in the locus, with greater numbers of repeats associated with higher mRNA levels. Because there is no information about the transcriptional regulation of these common alleles, we used oligonucleotide affinity chromatography and liquid chromatography-mass spectrometry to identify nuclear proteins that interact with the -794 CATT5-8 site. An analysis of monocyte nuclear lysates revealed that the transcription factor ICBP90 (also known as UHRF1) is the major protein interacting with the MIF microsatellite. We found that ICBP90 is essential for MIF transcription from monocytes/macrophages, B and T lymphocytes, and synovial fibroblasts, and TLR-induced MIF transcription is regulated in an ICBP90- and -794 CATT5-8 length-dependent manner. Whole-genome transcription analysis of ICBP90 shRNA-treated rheumatoid synoviocytes uncovered a subset of proinflammatory and immune response genes that overlapped with those regulated by MIF shRNA. In addition, the expression levels of ICBP90 and MIF were correlated in joint synovia from patients with rheumatoid arthritis. These findings identify ICBP90 as a key regulator of MIF transcription and provide functional insight into the regulation of the polymorphic MIF locus.
BACKGROUND: Colorectal cancer (CRC) is the highest leading cause of cancer-related mortality in Taiwan. Macrophage migration inhibitory factor (MIF) has recently been defined as a novel protumorigenic factor that promotes cell proliferation, migration, and inva
sion. The aim of the present study is to identify the association between MIF gene polymorphism and CRC. METHODS: A case-control study was designed to test the hypothesis. A total of 192 biopsy-diagnosed CRC patients (CRC) and 256 healthy subjects (control) were recruited. Genotyping of four single nucleotide polymorphism (SNPs; rs755662, rs11548059, rs1049829, rs1803976) at chromosome positions 755662 (5' UTR), 11548059 (exon2), 1049829 (exon2), 1803976 (exon3) was performed using a Taqman SNP genotyping assay. RESULTS: There is a significant difference in genotype frequency distribution of rs755662 polymorphism between CRC patients and controls (P = 0.011). No significant difference was found in the frequency distribution of rs11548059, rs1049829, rs1803976 polymorphism in CRC patients and controls (P = 0.660, P = 0.700, and P = 0.959, respectively). Moreover, the MIF-173 SNP was also significantly associated with young patients (age < 50 years, P = 0.026) late stage (Stage IV, P = 0.038) and poor differentiation group (P = 0.040). Compared to the control group, the MIF-173 SNP also significantly associated with patients with stages III and IV (P = 0.034 and 0.003, respectively). CONCLUSION: The presence of MIF-173 (G/C) gene polymorphism (rs755662) was associated with susceptibility, patient age, and stages of CRC in Taiwanese.
Melanoma is believed to be a highly immunogenic tumor and recent developments in immunotherapies are promising. IFN-gamma produced by immune cells has a crucial role in tumor immune surveillance; however, it has also been reported to be pro-tumorigenic. In the current study, we found that IFN-gamma
enhances the expression of CD74, which interacts with its ligand, macrophage migration inhibitory factor (MIF), and thereby activates the PI3K/AKT pathway in melanoma, promoting tumor survival. IFN-gamma increased phosphorylation of AKT Ser473 and upregulated total cell surface expression of CD74 in human melanoma cell lines tested. CD74 was highly expressed in melanoma tissues. Moreover, the expression of CD74 on tumor cells correlated with plasma IFN-gamma levels in melanoma patient samples. In our analysis of melanoma cell lines, all produced MIF constitutively. Blockade of CD74-MIF interaction reduced AKT phosphorylation and expression of pro-tumorigenic molecules, including IL-6, IL-8, and BCL-2. Inhibition of CD74-MIF interaction significantly suppressed tumor growth in the presence of IFN-gamma in our xenograft mouse model. Thus, we conclude that IFN-gamma promotes melanoma cell survival by regulating CD74-MIF signaling, suggesting that targeting the CD74-MIF interaction under IFN-gamma-stimulatory conditions would be an effective therapeutic approach for melanoma.
Macrophage migration inhibitory factor (MIF) is a cytokine that has broad effects on immune system and inflammatory response. A growing body of evidence implicates the role of MIF in tumor growth and metastasis. Lysophosphat
idic acid (LPA), a bioactive lipid mediator, regulates colon cancer cell proliferation, invasion, and survival through LPA2 receptor. Loss of LPA2 results in decreased expression of MIF in a rodent model of colon cancer, but the mechanism of MIF regulation by LPA is yet to be determined. In this study, we show that LPA transcriptionally regulates MIF expression in colon cancer cells. MIF knockdown decreased LPA-mediated proliferation of HCT116 human adenocarcinoma cells without altering the basal proliferation rates. Conversely, extracellular recombinant MIF stimulated cell proliferation, suggesting that the effect of MIF may in part be mediated through activation of surface receptor. We have shown recently that LPA increases hypoxia-inducible factor 1alpha (HIF1alpha) expression. We found that MIF regulation by LPA was ablated by knockdown of HIF1alpha, indicating that MIF is a transcriptional target of HIF1alpha. Conversely, knockdown of MIF ablated an increase in HIF1alpha expression in LPA-treated cells, suggesting a reciprocal relationship between HIF1alpha and MIF. LPA stimulated co-immunoprecipitation of HIF1alpha and MIF, indicating that their association is necessary for stabilization of HIF1alpha. It has been shown previously that CSN9 signalosome subunit 5 (CSN5) interacts with HIF1alpha to stabilize HIF1alpha under aerobic conditions. We found that LPA did not alter expression of CSN5, but stimulated its interaction with HIF1alpha and MIF. Depletion of CSN5 mitigated the association between HIF1alpha and MIF, indicating that CSN5 acts as a physical link. We suggest that HIF1alpha, MIF, and CSN5 form a ternary complex whose formation is necessary to prevent degradation of HIF1alpha under aerobic conditions.
derived macrophage migration inhibitory factor (MIF) is necessary for the immunosuppressive function of tumor-associated macrophages and MDSCs in mouse models of melanoma. In the current study, we sought to determine whether MIF contributes to human melanoma MDSC induction and T-cell immunosuppression using melanoma patient-derived MDSCs and an ex vivo coculture model of human melanoma-induced MDSC. We now report that circulating MDSCs isolated from late-stage melanoma patients are reliant upon MIF for suppression of antigen-independent T-cell activation and that MIF is necessary for maximal reactive oxygen species generation in these cells. Moreover, inhibition of MIF results in a functional reversion from immunosuppressive MDSC to an immunostimulatory dendritic cell (DC)-like phenotype that is at least partly due to reductions in MDSC prostaglandin E(2) (PGE(2)). These findings indicate that monocyte-derived MIF is centrally involved in human monocytic MDSC induction/immunosuppressive function and that therapeutic targeting of MIF may provide a novel means of inducing antitumor DC responses in late-stage melanoma patients.
BACKGROUND/AIM: To determine whether macrophage migration inhibitory factor (MIF) and monocyte chemoattractant protein-1 (MCP-1) levels in patients with hepatitis B (HB) are different than in normal individuals and whether the HB surface antigen (HBs
Ag) level and viral load are correlated with each other and with the two aforementioned parameters. MATERIALS AND METHODS: Sera were obtained from 52 chronic active HB (CAHB) patients and 33 healthy controls, and their MIF and MCP-1 levels were measured. Statistical analyses were performed. A value of P < 0.05 was considered statistically significant. RESULTS: The MIF and MCP-1 values of the control group were increased compared to those of the CAHB group. The MIF and MCP-1 levels were negatively correlated with HBs Ag levels and viral loads. The MIF and MCP-1 levels were positively correlated. The HBs Ag levels and the log10 of the viral loads were positively correlated. CONCLUSION: We conclude that the negative correlation of MIF and MCP-1 with viral load and HBs Ag levels may be due to T-cell deficiency, antinuclear antibody seropositivity, and/or inhibition of chemokine ligand 2 receptors by viral antigens. More studies with a greater number of subjects are needed to evaluate the potential role of MIF and MCP in CAHB.
An emerging body of data indicates that the protein mediator described originally as macrophage migration inhibitory factor (MIF) exerts a central and wide ranging role in host inflammatory responses. MIF is a major constitu
ent of corticotrophic cells within the anterior pituitary gland and is secreted into the circulation in a hormone-like fashion. MIF also exists performed in monocytes/macrophages and is a pivotal mediator in the host response to endotoxic shock. To gain further insight into the biologic expression of this protein that encompasses components of both the immune and the endocrine systems, we have cloned the mouse MIF gene and identified potential regulatory sequences present within the 5'-proximal promoter region. The gene for mouse MIF is located on chromosome 10, spans approximately 1 kb, and shares a high degree of structural homology with its human counterpart. Of note, the consensus enhancer/promoter motifs identified include both inflammatory/growth factor-related elements and sites associated with the genes for certain peptide hormones. We also report the structures of two MIF pseudogenes that account for early observations suggesting that mouse MIF is encoded by a highly homologous multigene family.
Baysal E, etal., Int J Pediatr Otorhinolaryngol. 2013 Mar;77(3):338-40. doi: 10.1016/j.ijporl.2012.11.020. Epub 2012 Dec 14.
OBJECTIVES: Mannose-binding lectin and macrophage migration inhibitory factor gene polymorphisms are associated with several acute/chronic autoimmune or inflammatory diseases. The aim of this study was to investigate if there was any association between mannose-binding lectin 2 (MBL2) and macrophag
e migration inhibitory factor (MIF) gene polymorphisms and profound congenital sensorineural hearing loss in children who underwent cochlear implantation. METHODS: A total of 62 patients with congenital hearing loss and 80 age- and sex-matched healthy controls were evaluated for codon 54 A/B polymorphisms in MBL2 and the-173 G/C polymorphism in MIF by using the polymerase chain reaction and restriction fragment length polymorphism method. RESULTS: The frequency of the BB genotype of MBL2 and MIF -173 GC genotype were statistically significantly higher in the patient group than in the controls (p=0.0127, p=0.0408, respectively). CONCLUSION: In this study, we found that a subject who is homozygous for the variant allele B of codon 54 of the MBL2and heterozygous for variant allele C of -173 MIF has a risk factor for sensorineural hearing loss.
Macrophage migration inhibitory factor (MIF), a putative cytokine involved in inflammatory and immune responses, was identified in rat peritoneal macrophages by Western blot analysis and its secretion into culture medium by enzyme-linked immunosorbent assay. To
clarify the possibility of vitamin E as an immune modulator, we investigated the effect of vitamin E on MIF production in macrophages in response to calcium ionophore A23187 and lipopolysaccharide (LPS). Intraperitoneal injections of vitamin E (5 mg per rat) for 6 successive days resulted in a significant increase of alpha-tocopherol content in peritoneal macrophages. Alpha-tocopherol content of macrophages in vitamin E-treated rats was 478.3 +/- 90.7 ng/10(6) cells, whereas in control rats it was 1.5 +/- 0.5 ng/10(6) cells. For the control macrophages, total MIF content of the medium (2.5 x 10(6) cells/18 ml) without stimulation was 40.7 +/- 3.6 ng after 14 h culture, whereas stimulation with calcium ionophore A23187 (400 nM) and LPS (5.0 microg/ml) induced the elevation of MIF content to 65.9 +/- 7.5 ng and 74.3 +/- 10.4 ng, respectively (p < 0.05, n = 3). On the other hand, vitamin E-enriched macrophages without stimulation showed less MIF content (14.0 +/- 4.2 ng) than the control (p < 0.05, n = 3). Similarly, the increase of MIF of vitamin E-treated macrophages was significantly suppressed after stimulation with calcium ionophore A23187 or LPS, compared with the control macrophages (p < 0.01, n = 3). From analysis of intracellular MIF content by Western blot, we found no alteration of intracellular MIF content of vitamin E-macrophages, in contrast to the decreased content of control stimulated-macrophages, showing that vitamin E suppressed MIF secretion into the culture medium. Taken together, these results indicate that vitamin E may contribute to the regulation of inflammatory and immune responses through regulation of MIF secretion, possibly by modulating macrophage-membrane architecture.
Nakamaru Y, etal., Cytokine. 2005 Jul 21;31(2):103-8.
Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine whose expression has been found to be critical to the generation of antigen-specific immune responses. Recent studies suggested that MIF played a rol
e in the initiation and maintenance of allergic diseases. To elucidate MIF's role in the pathogenesis of allergic rhinitis (AR), we sensitized MIF-deficient gene knockout (KO) mice and wild-type (WT) mice intraperitoneally with ovalbumin (OVA) and compared their clinical symptoms and allergic responses after intranasal challenge. Antigen-induced nasal symptoms were significantly reduced in MIF KO mice compared to WT mice. Histological examination of nasal mucosa showed that the number of infiltrating eosinophils in MIF KO mice was significantly lower than that in WT mice (P < 0.05). The concentration of TNF-alpha in nasal mucosa was also significantly lower in MIF KO mice than in WT mice (P < 0.05). We have demonstrated that the absence of MIF affects several aspects of experimental AR. One mechanism by which these effects might be mediated is by down regulating TNF-alpha. The block of allergic inflammation in MIF KO mice suggests that MIF may play a role in the allergic response.
BACKGROUND: Deposition of uric acid in the kidney can lead to progressive tubulointerstitial injury with granuloma formation. We hypothesized that uric acid crystal deposition may induce granuloma formation by stimulating local expression of macrophage migration inhibitory factor (MIF
weight:700;'>MIF), which is a known mediator of delayed type hypersensitivity (DTH). MATERIALS AND METHODS: A model of acute uric acid nephropathy was induced in rats by the administration of oxonic acid (an inhibitor of uricase), together with uric acid supplements. MIF expression and local cellular response were examined by in situ hybridization and immunohistochemistry. RESULTS: Kidney tissue examined at 35 days posttreatment showed widespread tubulointerstitial damage with intratubular uric acid crystal deposition and granuloma formation. Tubules within the areas of granuloma showed a six-fold increase in MIF mRNA, compared with uninvolved areas by in situ hybridization. Moreover, the areas of increased MIF mRNA expression correlated with sites of dense accumulation of macrophages and T cells, and these cells were activated when assessed by the expression of interleukin-2R (IL-2R) and (MHC) class II. Interestingly, cytoplasmic staining for MIF protein in the uric acid (UA) crystal-associated granulomatous lesions was reduced, indicating a rapid MIF secretion by damaged tubules and macrophages secondary to uric acid crystal stimulation. This was confirmed by the demonstration of a marked increase in urinary MIF protein by Western blot analysis. Control rats fed either a normal diet or only oxonic acid had no discernible evidence of renal disease by routine light microscopy and minimal tubular expression of MIF mRNA and protein. CONCLUSIONS: These data suggest that intrarenal granulomas in urate nephropathy may be the consequence of a crystal induced DTH reaction mediated by MIF.
In addition to the host immune response, genetic and environmental factors play crucial roles in the manifestation of hepatitis B virus (HBV) infection. The macrophage migration inhibitory factor (MIF) -173G/C polymorphism (rs755622), located in the promoter reg
ion of MIF, may play integral roles in diverse processes, including the immune response. Thus, the MIF -173G/C polymorphism may influence the immune response to HBV during natural infection. We investigated whether the MIF -173G/C polymorphism was associated with susceptibility to HBV infection in a Chinese Han population. A total of 596 HBV infection cases and 612 age-matched controls were recruited for the study. Genotyping of the MIF -173G/C polymorphism was performed using the allele-specific polymerase chain reaction method. The frequencies of the alleles and genotypes in patients and controls were compared using the chi(2) test. Carriers of the variant C allele in MIF -173 G/C were at significantly higher risk of HBV infection than carriers of the wild-type allele (P = 0.032, odds ratio = 0.799, 95% confidence interval = 0.651-0.981). However, there was no significant difference in the distribution of MIF -173G/C genotypes between case and control groups in either population (P = 0.096, degrees of freedom = 2). Our findings indicate that the G to C base change in MIF -173 G/C confers an increased risk of development of HBV infection by altering the expression of MIF in our Chinese Han population.
Hu XL, etal., Sichuan Da Xue Xue Bao Yi Xue Ban. 2009 Mar;40(2):260-2, 267.
OBJECTIVE: To investigate whether hypoxia could induce the expression of MIF in vascular smooth muscle cells (VSMCs). METHODS: Rat vascular smooth muscle cells (A7r5 from ATCC) were cultured under hypoxia condition (37 degrees C, 5% CO2, 1%
O2) and normoxia condition (37 degrees C, 5% CO2, 20% O2) for 2, 4, 12, 24 or 48 hours respectively. MIF mRNA expression was detected by reverse transcriptase and polymerase chain reaction (RT-PCR). MIF protein expression was determined by Enzyme-Linked Immunosorbent Assay (ELISA). RESULTS: Expression of MIF mRNA was up-regulated as early as 2 hours in VSMCs after being exposed to hypoxia condition, which remained the elevated level up to 48 hours. Meanwhile, MIF protein level increased after hypoxia treatment for 2 hours, and maintained elevated status up to 48 hours. CONCLUSION: Hypoxia could significantly induce MIF expression in VSMCs. MIF might be an important factor in the patho-physiological response of VSMCs to hypoxia.
Zhang C, etal., Zhonghua Yi Xue Yi Chuan Xue Za Zhi. 2016 Feb;33(1):85-90. doi: 10.3760/cma.j.issn.1003-9406.2016.01.021.
OBJECTIVE: To investigate the interaction of single nucleotide polymorphisms of macrophage migration inhibitory factor (MIF) gene -173G/C and glutathione peroxidase 1(GPX1) gene 594C/T polymorphisms and high-fat diet in ulcerative colitis (UC). METHODS: The gene
tic polymorphisms of MIF -173G/C and GPX1 594C/T were determined with a polymorphism-polymerase chain reaction (PCR)-endonuclease method in peripheral blood leukocytes derived from 1500 UC cases and 1500 healthy controls. RESULTS: The frequencies of MIF -173CC and GPX1 594TT were 55.60% and 55.73% in the UC cases and 16.67% and 16.47% in the healthy controls, respectively. Statistical tests also showed a significant difference in the frequencies between the two groups (P<0.01; P<0.01, respectively). Individuals carrying MIF -173CC also had a significantly higher risk of UC compared with those with MIF -173GG (OR=6.8662, 95%CI: 4.5384-9.6158). Individuals carrying GPX1 594TT had a high risk of UC (OR=7.0854, 95%CI: 4.4702-10.5283). Combined analysis showed that the percentages of MIF -173CC/GPX1 594TT in the UC and control groups were 31.00% and 2.73%, respectively (P<0.01). Individuals carrying MIF -173CC/GPX1 594TT had a high risk of UC (OR=49.0113, 95%CI: 31.7364-61.8205). The high-fat diet rate of the case group was significantly higher than that of the control group (OR=3.3248, 95%CI: 1.9461-5.0193, P<0.01), and statistic analysis suggested an interaction between high-fat diet and MIF -173CC and GPX1 594TT which increase risk of UC (gamma =6.9293; gamma =6.9942). CONCLUSION: MIF -173CC and GPX1 594TT and high-fat diet are the risk factors for UC, and the significant interactions between genetic polymorphisms of MIF -173G/C, GPX1 594C/T and high-fat diet may increase the risk for UC.
Yang S, etal., Cancer Res. 2016 Jul 1;76(13):3838-50. doi: 10.1158/0008-5472.CAN-15-2841. Epub 2016 Apr 20.
Pancreatic cancers with aberrant expression of macrophage migration inhibitory factor (MIF) are particularly aggressive. To identify key signaling pathways that drive disease aggressiveness in tumors with high MIF expression
, we analyzed the expression of coding and noncoding genes in high and low MIF-expressing tumors in multiple cohorts of pancreatic ductal adenocarcinoma (PDAC) patients. The key genes and pathways identified were linked to patient survival and were mechanistically, functionally, and clinically characterized using cell lines, a genetically engineered mouse model, and PDAC patient cohorts. Here, we report evidence of a novel MIF-driven signaling pathway that inhibits the orphan nuclear receptor NR3C2, a previously undescribed tumor suppressor that impacts aggressiveness and survival in PDAC. Mechanistically, MIF upregulated miR-301b that targeted NR3C2 and suppressed its expression. PDAC tumors expressing high levels of MIF displayed elevated levels of miR-301b and reduced levels of NR3C2. In addition, reduced levels of NR3C2 expression correlated with poorer survival in multiple independent cohorts of PDAC patients. Functional analysis showed that NR3C2 inhibited epithelial-to-mesenchymal transition and enhanced sensitivity to the gemcitabine, a chemotherapeutic drug used in PDAC standard of care. Furthermore, genetic deletion of MIF disrupted a MIF-mir-301b-NR3C2 signaling axis, reducing metastasis and prolonging survival in a genetically engineered mouse model of PDAC. Taken together, our results offer a preclinical proof of principle for candidate therapies to target a newly described MIF-miR-301b-NR3C2 signaling axis for PDAC management. Cancer Res; 76(13); 3838-50. (c)2016 AACR.
In order to investigate the influence of functional polymorphisms of macrophage migration inhibitory factor (MIF), Fcg receptors CD16A (FCGR3A) and CD32A (FCGR2A) genes on susceptibility to pulmonary tuberculosis (PTB) in the Moroccan population, we analyzed 123
patients with PTB and 154 healthy controls. The genotyping for MIF-173 (G/C) (rs755622), FCGR2A-131H/R (rs1801274) and FCGR3A-158V/F (rs396991) was carried out using TaqMan SNP Genotyping Assay method. We found a statistically significant increase of the MIF -173CC homozygote genotype and MIF -173*C allele frequencies in PTB patients compared with healthy controls (17.07%versus 5.84%, P = 0.003; and 35.37%versus 26.30%, P = 0.02; respectively). In contrast, no association was observed between FCGR2A-131H/R and FCGR3A-158V/F polymorphisms and tuberculosis disease. Our finding suggests that MIF -173*C variant may play an important role in the development of active tuberculosis.
Das R, etal., Cytokine. 2016 Feb;78:51-4. doi: 10.1016/j.cyto.2015.11.021. Epub 2015 Nov 28.
Infection with mosquito-borne West Nile virus (WNV) is usually asymptomatic but can lead to severe WNV encephalitis. The innate cytokine, macrophage migration inhibitory factor (MIF), is elevated in patients with WNV encephalitis and promotes viral neuroinvasion
and mortality in animal models. In a case-control study, we examined functional polymorphisms in the MIF locus in a cohort of 454 North American patients with neuroinvasive WNV disease and found patients homozygous for high-expression MIF alleles to be >20-fold (p=0.008) more likely to have WNV encephalitis. These data indicate that MIF is an important determinant of severity of WNV neuropathogenesis and may be a therapeutic target.
Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine that plays an important role in pathogenesis of asthma. A high level of MIF has been detected in bronchoalveolar lavage fluid, serum and sputum in as
thma. Polymorphisms associated with inflammatory diseases exist in the promoter region of MIF, which alter its expression. The aim of this study was to evaluate the potential relationship between functional polymorphisms of MIF and childhood asthma in a northeastern Chinese population. The study consisted of a set of 41 trios and an independent sample set of 189 childhood asthma patients and 261 healthy controls. We genotyped MIF-173G/C using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Additionally, MIF-794CATT(5-8) microsatellite polymorphism was genotyped by polyacrylamide gel electrophoresis (PAGE). A statistically significant difference in the distribution of the MIF-173C allele between patients and controls [P = 0.01, odds ratio (OR) = 1.55, 95% confidence interval (CI) = 1.13-2.18] was observed. In addition, the frequency of the MIF-173CC genotype was higher in asthmatic children (P < 0.01, OR = 3.37, 95% CI = 1.27-8.93). No difference in the distribution of CATT(5-8) was found between patients and healthy controls. Haplotype analysis showed that only the MIFCATT(7)-173C haplotype was associated with greater susceptibility to childhood asthma (P = 0.03, OR = 1.54, 95% CI 1.03-2.28). However, the transmission disequilibrium test confirmed a positive association between MIF-173G/C and childhood asthma (P = 0.005), and the absence of an association between the MIF-794CATT(5-8) and the disease. These preliminary results suggest an association between the MIF-173C allele and childhood asthma.
Suzuki T, etal., Brain Res. 1999 Jan 23;816(2):457-62.
Macrophage migration inhibitory factor (MIF) has been characterized as a proinflammatory cytokine, hormone, and immunomodulator. We previously demonstrated the distribution of MIF in the adult rat brain and revealed its expr
ession in neurons as well as glial cells. In this study, we investigated the localization of MIF in the developing rat brain from embryonic day (ED) 13 to ED19, and after birth from postnatal day (PD) 1 to PD28 using both immunohistochemistry and in situ hybridization. On ED16, the signals of MIF mRNA were high in the ventricular, subventricular, and intermediate zones of the telencephalon, in which 'neuropoietic' progenitor cells proliferate and migrate from the ventricular zone to the superficial layer in the cerebral cortex. The mRNA expression was detected throughout the postnatal period, and intense signals of the transcript were seen in the ventricle and in layers I, II and III of the cerebral cortex at PD5. Similarly, positive staining of MIF protein was seen in the ventricular zone by immunohistochemical analysis, although the positively stained area appeared to be smaller than the mRNA expression. Taken together, these results suggest that the increase in MIF mRNA in the developing brain reflects the growth and maturation of neurons and glial cells.
The purpose of this study was to investigate whether baicalin, a Chinese herbal extract, down-regulates the expression of macrophage migration inhibitory factor (MIF), an inflammatory factor that regulates the function of macrophages (MPhi), in rats with trini
trobenzene sulphonic acid (TNBS)-induced ulcerative colitis (UC). The results showed that baicalin simultaneously down-regulated the expression of MIF, the quantity of MPhis and the amount of MPhi-related cytokines, including macrophage chemotactic factor-1 (MCP-1, CCL2) and macrophage inflammatory protein-3alpha (MIP-3alpha, CCL20), in rats with UC. There was no statistical difference between baicailin and mesalazine in down-regulating the expression of MIF. Our study demonstrated that baicalin, an inexpensive but effective monomer, could be a new and alternative pharmaceutical for UC.
Surface expressed proteoglycans mediate the binding of cytokines and chemokines to the cell surface and promote migration of various tumor cell types including epithelial tumor cells. We here demonstrate that binding of the chemokine-like inflammatory cytokine macrophage migration inhibitory factor
(MIF) to epithelial lung and breast tumor cell lines A549 and MDA-MB231 is sensitive to enzymatic digestion of heparan sulphate chains and competitive inhibition with heparin. Moreover, MIF interaction with heparin was confirmed by chromatography and a structural comparison indicated a possible heparin binding site. These results suggested that proteoglycans carrying heparan sulphate chains are involved in MIF binding. Using shRNA-mediated gene silencing, we identified syndecan-1 as the predominant proteoglycan required for the interaction with MIF. MIF binding was decreased by induction of proteolytic shedding of syndecan-1, which could be prevented by inhibition of the metalloproteinases involved in this process. Finally, MIF induced the chemotactic migration of A549 cells, wound closure and invasion into matrigel without affecting cell proliferation. These MIF-induced responses were abrogated by heparin or by silencing of syndecan-1. Thus, our study indicates that syndecan-1 on epithelial tumor cells promotes MIF binding and MIF-mediated cell migration. This may represent a relevant mechanism through which MIF enhances tumor cell motility and metastasis.
Overexpression of C-X-C chemokine receptor type 4 (CXCR4) has been shown in several cancers, including non-small cell lung cancer (NSCLC) and is linked to early metastasis and worse prognosis. The crosstalk between cancer cells and tumor stroma promotes the growth and metastasis and CXCR4 signaling
is a key element of this crosstalk. To test the effects of CXCR4 overexpression (CXCR4-OE), we transduced the human NSCLC cell line A549 by using a lentiviral vector. A 3D cell culture model showed generations of tumorspheres and the effects derived by the co-culturing of lung fibroblasts. Using a xenograft mouse model, we also studied the effects of CXCR4-OE in pulmonary cell engraftment and tumor burden in vivo. Our data indicate that CXCR4-OE leads to increased tumorsphere formation and epithelial-mesenchymal transition (EMT). CXCR4-OE by A549 cells resulted in a significant increase in the production of the CXCR4-ligand macrophage migration inhibitory factor (MIF) compared to those transduced with an empty vector (EV) or in which the CXCR4 expression was deleted (KO). In our in vitro system, we did not detect any production of the canonical CXCR4 ligand CXCL12. Autocrine MIF production and CXCR4 signaling are part of a self-perpetuating loop that amplifies tumor growth and EMT. Co-culture with lung fibroblasts further increased tumorsphere formation, partially driven by an increase in IL-6 production. When A549 cells were injected into murine lungs, we observed more abundant and significantly larger tumor lesions in recipients of CXCR4-OE A549 cells compared to those receiving EV or KO cells, consistent with our in vitro findings. Treatment of mice with the MIF antagonist ISO-1 resulted in significantly less tumor burden. In conclusion, our data highlight the role of the CXCR4-OE/MIF/IL-6 axis in epithelial mesenchymal crosstalk and NSCLC progression.
Mun SH, etal., J Bone Miner Res. 2013 Apr;28(4):948-59. doi: 10.1002/jbmr.1787.
CD74 is a type II transmembrane protein that can act as a receptor for macrophage migration inhibitory factor (MIF) and plays a role in MIF-regulated responses. We reported that MIF inhi
bited osteoclast formation and MIF knockout (KO) mice had decreased bone mass. We therefore examined if CD74 was involved in the ability of MIF to alter osteoclastogenesis in cultured bone marrow (BM) from wild-type (WT) and CD74-deficient (KO) male mice. We also measured the bone phenotype of CD74 KO male mice. Bone mass in the femur of 8-week-old mice was measured by micro-computed tomography and histomorphometry. Bone marrow cells from CD74 KO mice formed 15% more osteoclast-like cells (OCLs) with macrophage colony-stimulating factor (M-CSF) and receptor activator of NF-kappaB ligand (RANKL) (both at 30 ng/mL) compared to WT. Addition of MIF to WT cultures inhibited OCL formation by 16% but had no effect on CD74KO cultures. The number of colony forming unit granulocyte-macrophage (CFU-GM) in the bone marrow of CD74 KO mice was 26% greater than in WT controls. Trabecular bone volume (TBV) in the femurs of CD74 KO male mice was decreased by 26% compared to WT. In addition, cortical area and thickness were decreased by 14% and 11%, respectively. Histomorphometric analysis demonstrated that tartrate-resistant acid phosphatase (TRAP)(+) osteoclast number and area were significantly increased in CD74 KO by 35% and 43%, respectively compared to WT. Finally, we examined the effect of MIF on RANKL-induced-signaling pathways in bone marrow macrophage (BMM) cultures. MIF treatment decreased RANKL-induced nuclear factor of activated T cells, cytoplasmic 1 (NFATc1) and c-Fos protein in BMM cultures by 70% and 41%, respectively. Our data demonstrate that CD74 is required for MIF to affect in vitro osteoclastogenesis. Further, the bone phenotype of CD74 KO mice is similar to that of MIF KO mice. MIF treatment of WT cultures suppressed RANKL-induced activator protein 1 (AP-1) expression, which resulted in decreased osteoclast differentiation in vitro. We propose that CD74 plays a critical role in the MIF inhibition of osteoclastogenesis.
BACKGROUND: End stage renal disease (ESRD) patients are characterized by increased morbidity and mortality due to highest prevalence of cardiovascular disease. Macrophage migration inhibitory factor (MIF) is an inflammatory cytokine that controls cellular signal
ing in human physiology, pathophysiology, and diseases. Increased MIF plasma levels promote vascular inflammation and development of atherosclerosis. We have shown that MIF is associated with vascular dysfunction in ESRD patients. Whether hemodialysis (HD) affects circulating MIF plasma levels is unknown. We here aimed to investigate whether HD influences the circulating MIF pool in ESRD patients. METHODS AND RESULTS: An observational single-center study was conducted. MIF plasma levels in ESRD patients were assessed before, during, and after a HD session (n = 29). Healthy age-matched volunteers served as controls to compare correlations of MIF plasma levels with inflammatory plasma components (n = 20). MIF removed from the circulating blood pool could be detected in the dialysate and allowed for calculation of totally removed MIF (MIF content in dialysate 219+/-4 mug/HD-session). MIF plasma levels were markedly decreased 2 hour after initiation of HD (MIF plasma level pre-HD 84.8+/-6 ng/ml to intra-HD 61.2+/-5 ng/ml p<0.001) and were replenished already 20 min after termination of HD to basal levels (intra-HD 61.2+/-5 ng/ml to post-HD 79.8+/-5 ng/ml, p<0.001). CONCLUSION: MIF is a dialyzable plasma component that is effectively filtrated during HD from the patient blood pool in large amounts. After removal of remarkable amounts of MIF during a single HD session, MIF plasma pool is early reconstituted after termination of HD from unknown sources.
OBJECTIVE: The role of the cytokine, macrophage migration inhibition factor (MIF) was assessed in tuberculosis. This case-control study investigated whether commonly occurring functional MIF polymorphisms are associated with
active tuberculosis as well as with serum levels of MIF, IFN-gamma and TNF-alpha. METHODS: Two MIF promoter polymorphisms, a functional -794 CATT5-8 microsatellite repeat (rs5844572) and a -173G/C single-nucleotide polymorphism (rs755622), were analysed by PCR and PCR-RFLP, respectively, in 47 patients and 50 healthy subjects. The mRNA level of MIF was performed by real-time PCR (RT-PCR), and MIF, IFN-gamma and TNF-alpha serum levels were determined by ELISA. RESULTS: A significant increase of MIF mRNA expression and MIF protein level were found in patients compared to healthy controls. Meanwhile, the increase of IFN-gamma and TNF-alpha serum levels were confirmed. According to the profile of genetic model, a significant association was found of genotypes carrying the -794 CATT 7 or 8 and -173 C risk alleles with susceptibility to active tuberculosis and with a significant increase of MIF, IFN-gamma and TNF-alpha. CONCLUSIONS: These data suggested a distinct genetic and immunopathogenic basis for tuberculosis at the MIF locus. Serum MIF, IFN-gamma and TNF-alpha profiles distinguish tuberculosis from the more inflammatory phenotype and may play a role in pathogenesis and as biomarkers of active tuberculosis.
Kozak CA, etal., Genomics. 1995 Jun 10;27(3):405-11.
The single functional mouse gene for MIF (macrophage migration inhibitory factor) has been cloned from a P1 library, and its exon/intron structure determined and shown to resemble that of the human gene. The gene was mapped to chromosome 10 using two multilocus
crosses between laboratory strains and either Mus musculus musculus or Mus spretus. Nine additional loci containing related sequences, apparently all processed pseudogenes, were also mapped to chromosomes 1, 2, 3, 7, 8, 9, 12, 17, and 19. While most of these pseudogenes were found in inbred mice and M. spretus, some are species specific. This suggests that there have been active phases of pseudogene formation in Mus both before and after the separation of musculus and spretus. The human genome contains no pseudogenes; we assigned the human gene to chromosome 19, consistent with the location of mouse and human functional genes for MIF in a region of conserved linkage.
BACKGROUND: Pre-eclampsia (PE) is a hypertensive multisystem disorder, causing significant fetal-maternal mortality and morbidity worldwide. This study aims to define possible longitudinal predictive mRNA markers involved in the main pathogenic pathways of PE: inflammation [macrophage migration inh
ibitory factor (MIF)], hypoxia and oxidative stress [hypoxia inducible factor 1-alpha subunit (HIF1A) and beta-site APP-cleaving enzyme-2 (BACE2)] and endothelial dysfunction [endoglin (ENG), fms-related tyrosine kinase-1 (FLT1) and vascular endothelial growth factor (VEGF)]. METHODS: Peripheral blood was collected from 33 singleton pregnancies characterized by a high cardiovascular profile risk sampled consecutively at 6-16; 17-23; 24-30; 31-34; >/=35 weeks followed by the Obstetrics and Gynecology Unit of the San Raffaele Hospital in Milan. A real-time quantitative PCR reaction was performed on plasma RNA. RESULTS: Of the 33 women enrolled, nine developed PE. Until 23 weeks HIF1A was significantly higher in women who later developed PE compared to women who did not (p=0.049 and p=0.012 in the first and second blood collection). In the third time interval MIF (p=0.0005), FLT1 (p=0.024), ENG (p=0.0034) and BACE2 (p=0.044) appeared to be significantly increased while HIF1A was elevated even from 24 week onwards but not reaching the statistical significance. In the fourth time interval ENG mRNA still remained increased (p=0.037). CONCLUSIONS: HIF1A, marker of hypoxia and oxidative stress, and MIF, marker of inflammation, seemed to be the most promising RNA markers, suggesting that hypoxia, principally, and inflammation may play an important role in PE pathogenesis.
OBJECTIVE: To investigate whether two proinflammatory cytokines, high mobility group box 1 (HMGB1) and macrophage migration inhibitory factor (MIF) are involved in the development of Kawasaki disease (KD). METHODS: Twenty-seven patients with KD were included in
this study. Eleven patients with sepsis and 28 healthy children served as controls. Serum levels of HMGB1 and MIF were measured by corresponding enzyme-linked immunosorbent assay (ELISA) kits, respectively. Real-time polymerase chain reaction (PCR) was used to quantify the expression levels of genes encoding receptor for advanced glycation end-products (RAGE), an HMGB1 receptor, and CD74, an MIF receptor in peripheral blood mononuclear cells (PBMCs). RESULTS: Serum levels of HMGB1 and MIF in KD patients were the highest in the early acute phase and gradually decreased after defervescence. Serum HMGB1 and MIF levels in KD patients were significantly higher than those in controls (HMGB1, p<0.001; MIF, p<0.01). The expression levels of the RAGE gene and CD74 gene in KD patients were significantly higher than those in controls (RAGE, p<0.001; CD74, p<0.01). CONCLUSION: These data suggest that HMGB1 and MIF play an important role in immune responses in KD patients.
Rossi AG, etal., J Clin Invest. 1998 Jun 15;101(12):2869-74.
Macrophage migration inhibitory factor (MIF) is a potent proinflammatory mediator that has been shown to potentiate lethal endotoxemia and to play a potentially important regulatory role in human acute respiratory distress syndrome (ARDS). We have investigated w
hether eosinophils are an important source of MIF and whether MIF may be involved in the pathophysiology of asthma. Unstimulated human circulating eosinophils were found to contain preformed MIF. Stimulation of human eosinophils with phorbol myristate acetate in vitro yielded significant release of MIF protein. For example, eosinophils stimulated with phorbol myristate acetate (100 nM, 8 h, 37 degreesC) released 1,539+/-435 pg/10(6) cells of MIF, whereas unstimulated cells released barely detectable levels (< 142 pg/10(6) cells, mean+/-SEM, n = 8). This stimulated release was shown to be (a) concentration- and time-dependent, (b) partially blocked by the protein synthesis inhibitor cycloheximide, and (c) significantly inhibited by the protein kinase C inhibitor Ro-31,8220. In addition, we show that the physiological stimuli C5a and IL-5 also cause significant MIF release. Furthermore, bronchoalveolar lavage fluid obtained from asthmatic patients contains significantly elevated levels of MIF as compared to nonatopic normal volunteers (asthmatic, 797.5+/-92 pg/ml; controls, 274+/-91 pg/ml). These results highlight the potential importance of MIF in asthma and other eosinophil-dependent inflammatory disorders.
Luo Y, etal., Am J Physiol Lung Cell Mol Physiol. 2021 Jul 1;321(1):L6-L16. doi: 10.1152/ajplung.00288.2020. Epub 2021 Apr 21.
Macrophage migration inhibitory factor (MIF) inhibition can attenuate pulmonary fibrosis, but the antifibrotic mechanism is unclear. Here we investigated the antifibrotic effect of MIF knockdown in rats with bleomycin (BLM)-
induced pulmonary fibrosis. The results showed that MIF inhibition attenuated lung injury and extracellular matrix deposition; significantly reduced the levels of cytokines including transforming growth factor-β1 (TGF-β1), tumor necrosis factor-α (TNF-α), interleukin-17 (IL-17), hydroxyproline (hyp), fibroblast growth factor 23 (FGF23), and secreted phosphoprotein 1 (Spp1); and inhibited the expression of CD68, F4/80, and α-smooth muscle actin (α-SMA) protein. MIF inhibition is associated with reduction of proinflammatory mediators and macrophage infiltration in lungs. In addition, MIF knockdown in the day 14 group was significantly better than MIF knockdown in day 1 group in terms of the above mentioned cytokines TGF-β1, IL-17, TNF-α. MIF knockdown in day 14 group showed a better trend than MIF knockdown in day 1 group in inhibition of hyp and α-SMA formation. Furthermore, MIF inhibition downregulated the FGF23, Spp1, anti-integrin alpha 10 (Itga10), laminin subunit alpha 1 (Lama1), thrombospondin 2 (THBS2), and Serpin family B member 5 (SERPINB5) mRNA levels and the p-Smad2/3 protein level. MIF knockdown may inhibit fibrosis through the TGF-β1/Smads signaling pathway. In addition, MIF inhibition protects against vascular remodeling via Thbs2 and Serpinb5 signaling. In summary, our study showed that knockdown of MIF can significantly inhibit lung inflammation and fibrosis in rats with BLM-induced pulmonary fibrosis. The future development of inhibitors targeting MIF may contribute to the treatment of pulmonary fibrosis.
Stoppe C, etal., Antioxid Redox Signal. 2015 Oct 10;23(11):865-79. doi: 10.1089/ars.2014.6243. Epub 2015 Aug 11.
AIMS: Cardiac surgery involves myocardial ischemia/reperfusion (I/R) with potentially deleterious consequences. Macrophage migration inhibitory factor (MIF) is a stress-regulating chemokine-like cytokine that protects against I/R damage, but functional links wit
h its homolog, d-dopachrome tautomerase (MIF-2), and the circulating soluble receptor CD74 (sCD74) are unknown. In this study, we investigate the role of MIF, MIF-2, sCD74, and MIF genotypes in patients scheduled for elective single or complex surgical procedures such as coronary artery bypass grafting or valve replacement. RESULTS: MIF and MIF-2 levels significantly increased intraoperatively, whereas measured sCD74 decreased correspondingly. Circulating sCD74/MIF complexes were detectable in 50% of patients and enhanced MIF antioxidant activity. Intraoperative MIF levels were independently associated with a reduced risk for the development of atrial fibrillation (AF) (odds ratio 0.99 [0.98-1.00]; p=0.007). Circulating levels of MIF-2, but not MIF, were associated with an increased frequency of organ dysfunction and predicted the occurrence of AF (area under the curve [AUC]=0.663; p=0.041) and pneumonia (AUC=0.708; p=0.040). Patients with a high-expression MIF genotype exhibited a reduced incidence of organ dysfunction compared with patients with low-expression MIF genotypes (3 vs. 25; p=0.042). INNOVATION: The current study comprehensively highlights the kinetics and clinical relevance of MIF family proteins and the MIF genotype in cardiac surgery patients. CONCLUSION: Our findings suggest that increased MIF levels during cardiac surgery feature organ-protective properties during myocardial I/R, while the soluble MIF receptor, sCD74, may enhance MIF antioxidant activity. In contrast, high MIF-2 levels are predictive of the development of organ dysfunction. Importantly, we provide first evidence for a gene-phenotype relationship between variant MIF alleles and clinical outcome in cardiac surgery patients.
The profiling of cancer cell secretomes is considered to be a good strategy for identifying cancer-related biomarkers, but few studies have focused on identifying low-molecular-mass (LMr) proteins (<15 kDa) in cancer cell secretomes. Here, we used tricine-SDS-gel-assisted fractionation and LC-MS/MS
to systemically identify LMr proteins in the secretomes of five oral cavity squamous cell carcinoma (OSCC) cell lines. Cross-matching of these results with nine OSCC tissue transcriptome datasets allowed us to identify 33 LMr genes/proteins that were highly upregulated in OSCC tissues and secreted/released from OSCC cells. Immunohistochemistry and quantitative real-time PCR were used to verify the overexpression of two candidates, HMGA2 and MIF, in OSCC tissues. The overexpressions of both proteins were associated with cervical metastasis, perineural invasion, deeper tumor invasion, higher overall stage, and a poorer prognosis for post-treatment survival. Functional assays further revealed that both proteins promoted the migration and invasion of OSCC cell lines in vitro. Collectively, our data indicate that the tricine-SDS-gel/LC-MS/MS approach can be used to efficiently identify LMr proteins from OSCC cell secretomes, and suggest that HMGA2 and MIF could be potential tissue biomarkers for OSCC.
Different biomarkers are used to evaluate the severity of atopic dermatitis (AD); however, it remains difficult to determine the severity of localized skin lesions. MIF plays an essential role in the pathophysiology of skin inflammation. To establish whether the
MIF level in the stratum corneum (SC) serves as a marker of the severity of AD lesions, we examined the SC MIF (scMIF) levels in AD patients. The SC of the cheek, neck and upper arm skin was collected using tape stripping, and the scMIF levels were measured. Consequently, the scMIF levels were found to be significantly higher in the involved skin lesions than the uninvolved areas within the same patient. Moreover, the scMIF levels were significantly correlated with the severity of local skin lesions. These findings suggest that the scMIF level can be used as an effective marker for evaluating the local severity of AD.
Dickerhof N, etal., Free Radic Biol Med. 2015 Dec;89:498-511. doi: 10.1016/j.freeradbiomed.2015.09.009. Epub 2015 Oct 8.
Macrophage migration inhibitory factor (MIF) is an important player in the regulation of the inflammatory response. Elevated plasma MIF is found in sepsis, arthritis, cystic fibrosis and atherosclerosis. Immunomodulatory ac
tivities of MIF include the ability to promote survival and recruitment of inflammatory cells and to amplify pro-inflammatory cytokine production. MIF has an unusual nucleophilic N-terminal proline with catalytic tautomerase activity. It remains unclear whether tautomerase activity is required for MIF function, but small molecules that inhibit tautomerase activity also inhibit the pro-inflammatory activities of MIF. A prominent feature of the acute inflammatory response is neutrophil activation and production of reactive oxygen species, including myeloperoxidase (MPO)-derived hypochlorous acid and hypothiocyanous acid. We hypothesized that MPO-derived oxidants would oxidize the N-terminal proline of MIF and alter its biological activity. MIF was exposed to hypochlorous acid and hypothiocyanous acid and the oxidative modifications on MIF were examined by LC-MS/MS. Imine formation and carbamylation was observed on the N-terminal proline in response to MPO-dependent generation of hypochlorous and hypothiocyanous acid, respectively. These modifications led to a complete loss of tautomerase activity. However, modified MIF still increased CXCL-8/IL-8 production by peripheral blood mononuclear cells (PBMCs) and blocked neutrophil apoptosis, indicating that tautomerase activity is not essential for these biological functions. Pre-treatment of MIF with hypochlorous acid protected the protein from covalent modification by the MIF inhibitor 4-iodo-6-phenylpyrimidine (4-IPP). Therefore, oxidant generation at inflammatory sites may protect MIF from inactivation by more disruptive electrophiles, including drugs designed to target the tautomerase activity of MIF.
Tang Y, etal., Int J Clin Exp Pathol. 2015 Dec 1;8(12):15611-21. eCollection 2015.
The expression and functions of microRNA-451 have been studied in many human cancers. However, up to date, there is no study of microRNA-451 in renal cell carcinoma. In the present study, we aimed to investigate the expression, biological functions and molecular mechanisms of microRNA-451 in renal c
ell carcinoma. microRNA-451 expression level in renal cell carcinoma tissues and cell lines was measured using quantitative Real-time PCR. By using CCK8 assay, cell migration and invasion assay, we explored the functions of microRNA-451 in renal cell carcinoma. Dual-Luciferase report assay, quantitative Real-time PCR and western blot were performed to explore the molecular mechanisms of microRNA-451 functions in renal cell carcinoma. Functional assays were also performed to explore the effects of endogenous MIF in renal cell carcinoma. In this study, we showed for the first time that microRNA-451 was significantly down-regulated in renal cell carcinomas tissues and cell lines. microRNA-451 expression level was correlated with histological grade and lymph node metastasis. In addition, microRNA-451 inhibited proliferation, migration and invasion of renal cell carcinomas cells. Moreover, MIF was identified as a target of microRNA-451, and down-regulation of MIF could mimic the suppressive functions of microRNA-451 in renal cell carcinomas, suggesting that microRNA-451 might be a novel therapeutic strategy for the treatment of renal cell carcinomas.
Luo JY, etal., Medicine (Baltimore). 2016 Jan;95(4):e2617. doi: 10.1097/MD.0000000000002617.
Inflammation plays an important role in the pathogenesis of atherosclerosis. Recent studies indicate that macrophage migration inhibitory factor (MIF) is a potent proinflammatory cytokine which mediates the inflammatory process during atherosclerosis. The polymo
rphism of MIF gene (rs755622 [-173G/C], rs1007888, and rs2096525) were genotyped by TaqMan single nucleotide polymorphism (SNP) genotyping assay in 320 patients with coronary artery disease (CAD) and 603 controls in a Chinese Kazakh population. Coronary angiography was performed on all CAD patients and Gensini score was used to assess the severity of coronary artery lesions. The frequency of the CC genotype and C allele of rs755622 were significantly higher in CAD patients than that in control subjects (8.4% vs. 5.1%, P < 0.001, 30.3% vs. 22.1%, P < 0.001, respectively). Multivariate logistic regression analysis showed that individuals with CC genotype or C allele had a higher risk for CAD (CC genotype vs. GG genotype, OR = 2.224, 95% CI, 1.239-3.992, P = 0.007, and C allele vs. G allele, OR = 1.473, 95% CI, 1.156-1.876, P = 0.002, respectively). Moreover, CAD patients with rs755622 C allele (CC + CG genotype) have higher levels of Gensini score when compared to C allele noncarriers (32.74 +/- 26.66 vs. 21.44 +/- 19.40, P < 0.001, adjusted). Our results suggested that the CC genotype and C allele of MIF rs755622 SNP may be a genetic marker for the risk of CAD and potentially predict the severity of CAD in Chinese Kazakh population.
The cytokine macrophage migration inhibitory factor (MIF) plays a critical role in inflammatory diseases and atherogenesis. We identify the chemokine receptors CXCR2 and CXCR4 as functional receptors for MIF. MIF
nt-weight:700;'>MIF triggered G(alphai)- and integrin-dependent arrest and chemotaxis of monocytes and T cells, rapid integrin activation and calcium influx through CXCR2 or CXCR4. MIF competed with cognate ligands for CXCR4 and CXCR2 binding, and directly bound to CXCR2. CXCR2 and CD74 formed a receptor complex, and monocyte arrest elicited by MIF in inflamed or atherosclerotic arteries involved both CXCR2 and CD74. In vivo, Mif deficiency impaired monocyte adhesion to the arterial wall in atherosclerosis-prone mice, and MIF-induced leukocyte recruitment required Il8rb (which encodes Cxcr2). Blockade of Mif but not of canonical ligands of Cxcr2 or Cxcr4 in mice with advanced atherosclerosis led to plaque regression and reduced monocyte and T-cell content in plaques. By activating both CXCR2 and CXCR4, MIF displays chemokine-like functions and acts as a major regulator of inflammatory cell recruitment and atherogenesis. Targeting MIF in individuals with manifest atherosclerosis can potentially be used to treat this condition.
The macrophage migration inhibitory factor (MIF) receptor CD74 is overexpressed in various neoplasms, mainly in hematologic tumors, and currently investigated in clinical studies. CD74 is quickly internalized and recycles after antibody binding, therefore it con
stitutes an attractive target for antibody-based treatment strategies. CD74 has been further described as one of the most up-regulated molecules in human glioblastomas. To assess the potential relevance for anti-CD74 treatment, we determined the cellular source and clinicopathologic relevance of CD74 expression in human gliomas by immunohistochemistry, immunofluorescence, immunoblotting, cell sorting analysis and quantitative polymerase chain reaction (qPCR). Furthermore, we fractionated glioblastoma cells and glioma-associated microglia/macrophages (GAMs) from primary tumors and compared CD74 expression in cellular fractions with whole tumor lysates. Our results show that CD74 is restricted to GAMs in vivo, while being absent in tumor cells, the latter strongly expressing its ligand MIF. Most interestingly, a higher amount of CD74-positive GAMs was associated with beneficial patient survival constituting an independent prognostic parameter and with an anti-tumoral M1 polarization. In summary, CD74 expression in human gliomas is restricted to GAMs and positively associated with patient survival. In conclusion, CD74 represents a positive prognostic marker most probably because of its association with an M1-polarized immune milieu in high-grade gliomas.
Hu CT, etal., Oncotarget. 2015 Sep 8;6(26):22410-23.
Growth and invasion of metastatic colorectal cancer (CRC) cells in the liver depend on microenvironment. Here, we showed that human hepatic sinusoidal endothelial cells (HHSECs) induce chemotaxis and outgrowth of CRC cells. Macrophage migration inhibitory factor (MIF
span>), released by HHSECs, stimulated chemotaxis of CRC cells. MIF secreted by HHSECs, but not by CRC cells themselves, promoted migration and epithelial-mesenchymal transition (EMT) and facilitated proliferation and apoptotic resistance of CRC cells. In orthotopic implantation models in nude mice, exogenous MIF stimulated growth of CRC cells and metastasis. Furthermore, MIF accelerated mobility of CRC cells by suppressing F-actin depolymerization and phosphorylating cofilin. Noteworthy, MIF levels were correlated with the size of hepatic metastases. We suggest that HHSECs and paracrine MIF promote initial migration and proliferation of CRC cells in the hepatic sinusoids to generate liver metastases.
Zhang M, etal., Cancer Gene Ther. 2015 Oct;22(10):463-74. doi: 10.1038/cgt.2015.42. Epub 2015 Sep 25.
Macrophage migration inhibitory factor (MIF) has been identified as a major gene product upregulated in breast cancer cells-tissues upon the accumulation of macrophages. However, regulatory role of MIF in tumor microenviron
ment is not well understood. Previously, we have developed small interfering RNA (siRNA)-loaded nanoparticle system to effectively reduce MIF expression in both breast cancer cells and macrophages. Using this nanoparticle system, in this study we demonstrated that the siRNA-induced MIF reduction in murine mammary cancer line 4T1 and human breast cancer line MDA-MB-231 resulted in significant reduction of cell proliferation and increase of apoptosis; the siRNA-induced MIF reduction in tumor-associated macrophages resulted in a significant reduction of surface expression of CD74 and CD206 and a significant increase of surface expression of major histocompatibility complex II, as well as intracellular expression of tumor necrosis factor-alpha and interleukin-2. A direct injection of the MIF-siRNA-loaded nanoparticles into 4T1 tumor in mice resulted in effective reduction of intratumoral MIF. This led to a reduction of tumor growth and metastasis. This also resulted in a reduction of circulating myeloid-derived suppressive cells both in number and in suppressive function. CD4 T-cell infiltration to tumor was increased. More importantly, this not only slowed the growth of treated 4T1 tumor, but also delayed the growth and metastasis of a contralateral untreated 4T1-luc tumor, suggesting the development of systemic antitumor responses. This study demonstrates for the first time that the siRNA-mediated intratumoral MIF reduction can induce antitumoral immune response via reducing systemic immune suppression.
BACKGROUND: Macrophage migration inhibitory factor (MIF) is a pluripotent cytokine involved in inflammation and immune responses as well as in cell growth. Although we previously demonstrated the presence of MIF in periphera
l nerves, and MIF mRNA expression was up-regulated after axotomy, the role of MIF in nerve injury and regeneration has not been evaluated. MATERIALS AND METHODS: To examine the potential role of MIF in nerve regeneration, we locally administered an anti-MIF polyclonal antibody into regenerating rat sciatic nerves using the silicone chamber model. The effect of the anti-MIF antibody on nerve regeneration was evaluated using an axonal reflex test. In addition, we carried out a terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling (TUNEL) assay and immunohistochemical analysis of the damaged nerve segments with regard to apoptosis-related proteins such as p53 to evaluate the effects of anti- MIF antibodies on apoptosis during the regeneration process. RESULTS: The regeneration length of the nerve in the anti-MIF antibody-treated group was significantly shorter than that in the non-immune rabbit IgG-treated group at weeks 2, 4 and 6 after surgery. TUNEL assay showed that a large number of apoptotic cells, mostly Schwann cells, were observed in the intratubal and distal nerve segments at weeks 4 and 6 after surgery by the anti-MIF antibody treatment. Consistent with these results, Ki-67-positive cells were significantly decreased by the anti-MIF antibody treatment. Immunohistochemical analyses revealed that p53 and, to a lesser extent, Fas were more up-regulated in the anti-MIF antibody-treated nerves than in the controls. CONCLUSION: Taken together, these results suggest that MIF plays an important role in acceleration of peripheral nerve regeneration and in prevention of Schwann cell apoptosis, mainly through overcoming the apoptotic effect of p53.
Nagata Y, etal., PLoS One. 2015 Feb 3;10(2):e0115593. doi: 10.1371/journal.pone.0115593. eCollection 2015.
Pollen is a clinically important airborne allergen and one of the major causes of allergic conjunctivitis. A subpopulation of patients with atopic dermatitis (AD) are also known to have exacerbated skin eruptions on the face, especially around the eyelids, after contact with pollen. This pollen-in
duced skin reaction is now known as pollen dermatitis. Macrophage migration inhibitory factor (MIF) is a pluripotent cytokine that plays an essential role in allergic inflammation. Recent findings suggest that MIF is involved in several allergic disorders, including AD. In this study, MIF knockout (KO), MIF transgenic (Tg) and WT littermate mice were immunized with ragweed (RW) pollen or Japanese cedar (JC) pollen and challenged via eye drops. We observed that the numbers of conjunctiva- and eyelid-infiltrating eosinophils were significantly increased in RW and JC pollen-sensitized MIF Tg compared with WT mice or MIF KO mice. The mRNA expression levels of eotaxin, interleukin (IL)-5 and IL-13 were increased in pollen-sensitized eyelid skin sites of MIF Tg mice. An in vitro analysis revealed that high eotaxin expression was induced in dermal fibroblasts by MIF combined with stimulation of IL-4 or IL-13. This eotaxin expression was inhibited by the treatment with CD74 siRNA in fibroblasts. These findings indicate that MIF can induce eosinophil accumulation in the conjunctiva and eyelid dermis exposed to pollen. Therefore, targeted inhibition of MIF might result as a new option to control pollen-induced allergic conjunctivitis and pollen dermatitis.
Uncaria rhynchophylla (Miq) Jack (UR) is a traditional Chinese herb and is used for the treatment of convulsive disorders, including epilepsy. Our previous study has shown that UR, as well as its major component rhynchophylline (RH), has an anticonvulsive effect and this effect is closely related to
its scavenging activities of oxygen free radicals. The purpose of the present study was to investigate the effect of (UR) on the expression of proteins using a proteomics analysis in Sprague-Dawley (SD) rats with kainic acid (KA)-induced epileptic seizures. We profiled the differentially expressed proteins on two-dimensional electrophoresis (2-DE) maps derived from the frontal cortex and hippocampus of rat brain tissue 24 hours after KA-induced epileptic seizures. The results indicated that macrophage migration inhibitory factor (MIF) and cyclophilin A were under expressed in frontal cortex by an average of 0.19- and 0.23-fold, respectively. In the frontal cortex, MIF and cyclophilin A were significantly decreased in the KA group and these decreases were confirmed by the Western blots. However, in the hippocampus, only cyclophilin A was significantly decreased in the KA group. In addition, in real-time quantitative PCR (Q-PCR), MIF and cyclophilin A gene expressions were also significantly under expressed in the frontal cortex, and only the cyclophilin A gene was also significantly under expressed in the hippocampus in the KA group. These under expressions of MIF and cyclophilin A could be overcome by the treatment of UR and RH. In conclusion, the under expressions of MIF and cyclophilin A in the frontal cortex and hippocampus in KA-treated rats, which were overcome by both UR and UH treatment, suggesting that both MIF and cyclophilin A at least partly participate in the anticonvulsive effect of UR.
Abdominal aortic aneurysm (AAA) is a localized dilatation of the arterial wall as a result of extensive breakdown of its structural proteins by matrix metalloproteinases (MMPs). AAA continuously expand and may eventually rupture, causing high mortality rates. The molecular processes underlying expan
sion and rupture of AAA are only poorly understood. In this study, evidence was sought for a direct involvement of macrophage migration inhibitory factor (MIF) in the pathogenesis of AAA through up-regulating MMPs, with particular reference to macrophages. To this end, expression and cellular localization of MIF were analyzed in human aortic wall samples of stable AAA and ruptured AAA, and compared with control aorta and atherosclerotic aorta (AS). MIF expression was up-regulated in stable AAA and further intensified in ruptured AAA. The increased aneurysmal MIF expression was paralleled by an enhanced expression of specific MMPs, viz. MMP-1, MMP-9, and MMP-12, and by a decrease of their inhibitors. Immunohistochemical analysis of AAA and AS showed MIF protein in endothelial cells, smooth muscle cells (SMCs), macrophages, and T cells. MMP-1 (in SMCs and macrophages) and MMP-9 (in macrophages) were colocalized with MIF at the cellular level in ruptured AAA. The up-regulation of aneurysmal MIF/MMP expression was associated with an increased content of cytotoxic T cells.
Although macrophages play an important role in lipid-induced glomerular injury, we know little of the mechanisms by which hyperlipidaemia induces monocyte recruitment. This study investigated the role of M-CSF and macrophage MIF in monocyte recruitment during th
e development of lipid-induced glomerular injury in the susceptible ExHC rat strain. Groups of five ExHC rats were fed a high cholesterol diet (HCD) containing 3% cholesterol, 0.6% sodium cholate and 15% olive oil, and killed after 3 days, 1, 2 or 6 weeks. Control animals were killed on day 0 or after 6 weeks on a normal diet. Animals were hypercholesterolaemic 3 days after the induction of the HCD, but showed no change in plasma triglycerides over the 6-week period. Glomerular macrophage accumulation was first evident at 1-2 weeks and increased up to week 6, when macrophage-derived foam cells were seen in almost all glomeruli, and segmental lesions and mild proteinuria were also evident. Combined in situ hybridization and immunohistochemistry staining demonstrated that, coincident with the induction of hypercholesterolaemia on day 3, there was marked up-regulation of M-CSF and MIF mRNA expression by intrinsic glomerular cells (mostly mesangial cells and podocytes) which preceded monocyte recruitment. There was a highly significant correlation between the number of M-CSF and MIF-positive cells and glomerular macrophage accumulation over the 6-week period. Although some glomerular macrophages and foam cells exhibited M-CSF and MIF expression, the major source of these molecules was intrinsic glomerular cells. No local macrophage proliferation was observed during the development of glomerular lesions. In conclusion, hypercholesterolaemia caused marked up-regulation of M-CSF and MIF expression by intrinsic glomerular cells, which correlated with monocyte recruitment and the development of lipid-induced glomerular injury. This is the first study to implicate local synthesis of MIF in the pathogenesis of lipid-induced lesions.
Excessive ethanol (EtOH) use leads to impaired memory and cognition. Using a rat model of binge-like intoxication, we tested whether elevated corticosterone (Cort) levels contribute to the neurotoxic consequences of EtOH exposure. Rats were adrenalectomized (Adx) and implanted with cholesterol pelle
ts, or cholesterol pellets containing Cort in order to achieve basal, medium, or high blood concentrations of Cort. Intragastric EtOH or an isocaloric control solution was given three times daily for 4 days to achieve blood alcohol levels ranging between 200 and 350 mg/dl. Mean 24-hour plasma levels of Cort were ∼110 and ∼40 ng/ml in intact EtOH-treated and intact control animals, respectively. Basal Cort replacement concentrations in EtOH-treated Adx animals did not exacerbate alcohol-induced neurodegeneration in the hippocampal dentate gyrus (DG) or the entorhinal cortex (EC) as observed by amino-cupric silver staining. In contrast, Cort replacement pellets resulting in plasma Cort levels twofold higher (medium) than normal, or greater than twofold higher (high) in Adx-Cort-EtOH animals increased neurodegeneration. In separate experiments, pharmacological blockade of the Type II glucocorticoid (GC) receptor was initiated with mifepristone (RU38486; 0, 5, 15 mg/kg/day, i.p.). At the higher dose, mifepristone decreased the number of degenerating hippocampal DG cells in binge-EtOH-treated intact animals, whereas, only a trend for reduction was observed in 15 mg/kg/day mifepristone-treated animals in the EC, as determined by fluoro-jade B staining. These results suggest that elevated circulating Cort in part mediates EtOH-induced neurotoxicity in the brain through activation of Type II GC receptors.
