Inflammatory and infectious processes evoke neuroendocrine and behavioral changes known as acute-phase response that includes activation of the hypothalamo-pituitary-adrenal (HPA) axis and reduction of food intake. Besides its action as the most important ACTH secretagogue, corticotrophin-releasing
factor (CRF), synthesized in the paraventricular nucleus (PVN), is also involved in the control of food intake. Alpha-melanocyte stimulating hormone (alpha-MSH) in the arcuate nucleus also plays a role in the energy homeostasis, possessing anorexigenic effects. To investigate the participation of neuropeptides involved in the regulation of food intake during endotoxemia, we administrated lipopolysaccharide (LPS) in sham-operated and adrenalectomized (ADX) male Wistar rats to evaluate food intake, hormone responses and Fos-CRF and Fos-alpha-MSH immunoreactivity in the PVN and arcuate nucleus, as well as CRF and POMC mRNA expression in these hypothalamic nuclei. In sham-operated rats, treatment with LPS (100 microg/kg) showed lower food intake, higher plasma ACTH and corticosterone levels, as well as an increase in Fos-CRF double labeled neurons and CRF mRNA expression in the PVN, with no changes in Fos-alpha-MSH immunoreactivity and POMC mRNA expression in the arcuate nucleus, compared to saline treated rats. After LPS treatment, ADX rats showed further increase in plasma ACTH levels, marked decrease of food intake, higher Fos-CRF immunoreactive neurons in the PVN and CRF mRNA expression, as well as an increase in Fos-alpha-MSH immunoreactivity and POMC mRNA expression in the arcuate nucleus, compared to sham-operated rats treated with LPS. In conclusion, the present data indicate that the marked hypophagia during endotoxemia following ADX is associated with an increased activation of CRF and POMC neurons in the hypothalamus and an increased mRNA expression of these neuropeptides.
Cholecystokinin (CCK) is a meal-related signal that activates brainstem neurons, which have reciprocal interconnections with hypothalamic paraventricular nucleus (PVN). Neurons that express corticotrophin-releasing factor (CRF) in the hypothalamus possess anorexigenic effects and are activated durin
g endotoxemia. This study investigated the effects of CCK1 receptor blockade on lipopolysaccharide (LPS) -induced hypophagia and hypothalamic CRF neuronal activation. Male Wistar rats were pretreated with specific CCK1 receptor antagonist (devazepide; 1 mg/Kg; i.p.) or vehicle; 30 min later they received LPS (100 mug/Kg; i.p.) or saline injection. Food intake, corticosterone responses and Fos-CRF and Fos-alpha-melanocyte-stimulating hormone (alpha-MSH) immunoreactivity in the hypothalamus and Fos-tyrosine hydroxylase (TH) immunoreactivity in the nucleus of the solitarious tract (NTS) were evaluated. In comparison with saline treatment, LPS administration decreased food intake and increased plasma corticosterone levels, as well as, Fos-CRF and Fos-TH double-labeled neurons in vehicle-pretreated rats; no change in Fos-alpha-MSH immunoreactivity was observed after LPS injection. In saline treated animals, devazepide pretreatment increased food intake, but it did not modify other parameters, compared with vehicle-pretreated rats. Devazepide pretreatment partially reversed LPS-induced hypophagia and Fos-CRF and brainstem neuronal activation. Devazepide did not modify the corticosterone and Fos-alpha-MSH responses in rats treated with LPS. In conclusion, the present data suggest that LPS-induced hypophagia is mediated at least in part by CCK effects, via CCK1 receptor, on NTS and hypothalamic CRF neurons.
Acute administration of lipopolysaccharide (LPS) from Gram-negative bacteria induces hypophagia. However, the repeated administration of LPS leads to desensitization of hypophagia, which is associated with increased hypothalamic p-AMPK expression. Because ghrelin and endocannabinoids modulate AMPK a
ctivity in the hypothalamus, we hypothesized that these neuromodulators play a role in the reversal of tolerance to hypophagia in rats under long-term exposure to LPS. Male Wistar rats were treated with single (1 LPS, 100μg/kg body weight, ip) or repeated injections of LPS over 6days (6 LPS). Food intake was reduced in the 1 LPS, but not in the 6 LPS group. 6 LPS rats showed an increased serum concentration of acylated ghrelin and reduced ghrelin receptor mRNA expression in the hypothalamus. Ghrelin injection (40μg/kg body weight, ip) increased food intake, body weight gain, p-AMPK hypothalamic expression, neuropeptide Y (NPY) and Agouti related peptide (AgRP) mRNA expression in control animals (Saline). However, in 6 LPS rats, ghrelin did not alter these parameters. Central administration of a CB1R antagonist (AM251, 200ng/μl in 5μl/rat) induced hypophagia in 6 LPS animals, suggesting that the endocannabinoid system contributes to preserved food intake during LPS tolerance. In the presence of AM251, the ability of ghrelin to phosphorylate AMPK in the hypothalamus of 6 LPS group was restored, but not its orexigenic effect. Our data highlight that the orexigenic effects of ghrelin require CB1R signaling downstream of AMPK activation. Moreover, CB1R-mediated pathways contribute to the absence of hypophagia during repeated exposure to endotoxin.
Borges BC, etal., Am J Physiol Endocrinol Metab. 2011 May;300(5):E858-69. Epub 2011 Feb 22.
Acute exposure to bacterial lipopolysaccharide (LPS) is a potent inducer of immune response as well as hypophagia. Nevertheless, desensitization of responses to LPS occurs during long-term exposure to endotoxin. We induced endotoxin tolerance, injecting repeated (6LPS) LPS doses compared with single
(1LPS) treatment. 1LPS, but not 6LPS group, showed decreased food intake and body weight, which was associated with an increased plasma leptin and higher mRNA expression of OB-Rb, MC4R, and SOCS3 in the hypothalamus. Hypophagia induced by 1LPS was associated with lower levels of 2-arachidonoylglycerol (2-AG), increased number of p-STAT3 neurons, and decreased AMP-activated protein kinase (AMPK) activity. Desensitization of hypophagia in the 6LPS group was related to high 2-AG, with no changes in p-STAT3 or increased p-AMPK. Leptin decreased food intake, body weight, 2-AG levels, and AMPK activity and enhanced p-STAT3 in control rats. However, leptin had no effects on 2-AG, p-STAT3, or p-AMPK in the 1LPS and 6LPS groups. Rats treated with HFD to induce leptin resistance showed neither hypophagia nor changes in p-STAT3 after 1LPS, suggesting that leptin and LPS recruit a common signaling pathway in the hypothalamus to modulate food intake reduction. Desensitization of hypophagia in response to repeated exposure to endotoxin is related to an inability of leptin to inhibit AMPK phosphorylation and 2-AG production and activate STAT3. SOCS3 is unlikely to underlie this resistance to leptin signaling in the endotoxin tolerance. The present model of prolonged inflammatory challenge may contribute to further investigations on mechanisms of leptin resistance.
Iacobucci I, etal., J Hematol Oncol. 2015 Nov 5;8:125. doi: 10.1186/s13045-015-0206-5.
BACKGROUND: Although progress in children, in adults, ALL still carries a dismal outcome. Here, we explored the in vitro and in vivo activity of PF-00477736 (Pfizer), a potent, selective ATP-competitive small-molecule inhibitor of checkpoint kinase 1 (Chk1) and with lower efficacy of checkpoint kin
ase 2 (Chk2). METHODS: The effectiveness of PF-00477736 as single agent in B-/T-ALL was evaluated in vitro and in vivo studies as a single agent. The efficacy of the compound in terms of cytotoxicity, induction of apoptosis, and changes in gene and protein expression was assessed using different B-/T-ALL cell lines. Finally, the action of PF-00477736 was assessed in vivo using leukemic mouse generated by a single administration of the tumorigenic agent N-ethyl-N-nitrosourea. RESULTS: Chk1 and Chk2 are overexpressed concomitant with the presence of genetic damage as suggested by the nuclear labeling for gamma-H2A.X (Ser139) in 68 % of ALL patients. In human B- and T-ALL cell lines, inhibition of Chk1/2 as a single treatment strategy efficiently triggered the Chk1-Cdc25-Cdc2 pathway resulting in a dose- and time-dependent cytotoxicity, induction of apoptosis, and increased DNA damage. Moreover, treatment with PF-00477736 showed efficacy ex vivo in primary leukemic blasts separated from 14 adult ALL patients and in vivo in mice transplanted with T-ALL, arguing in favor of its future clinical evaluation in leukemia. CONCLUSIONS: In vitro, ex vivo, and in vivo results support the inhibition of Chk1 as a new therapeutic strategy in acute lymphoblastic leukemia, and they provide a strong rationale for its future clinical investigation.
Doze VA, etal., Brain Res. 2009 Aug 18;1285:148-57. Epub 2009 Jun 18.
Tricyclic antidepressant (TCA) drugs are used for the treatment of chronic depression, obsessive-compulsive disorder (OCD), and anxiety-related disorders. Chronic use of TCA drugs increases the expression of alpha(1)-adrenergic receptors (alpha(1)-ARs). Yet, it is unclear whether increased alpha(1)-
AR expression contributes to the antidepressant effects of these drugs or if this effect is unrelated to their therapeutic benefit. In this study, mice expressing constitutively active mutant alpha(1A)-ARs (CAM alpha(1A)-AR) or CAM alpha(1B)-ARs were used to examine the effects of alpha(1A)- and alpha(1B)-AR signaling on rodent behavioral models of depression, OCD, and anxiety. CAM alpha(1A)-AR mice, but not CAM alpha(1B)-AR mice, exhibited antidepressant-like behavior in the tail suspension test and forced swim test. This behavior was reversed by prazosin, a selective alpha(1)-AR inverse agonist, and mimicked by chronically treating wild type mice with cirazoline, an alpha(1A)-AR agonist. Marble burying behavior, commonly used to model OCD in rodents, was significantly decreased in CAM alpha(1A)-AR mice but not in CAM alpha(1B)-AR mice. In contrast, no significant differences in anxiety-related behavior were observed between wild type, CAM alpha(1A)-AR, and CAM alpha(1B)-AR animals in the elevated plus maze and light/dark box. This is the first study to demonstrate that alpha(1A)- and alpha(1B)-ARs differentially modulate antidepressant-like behavior in the mouse. These data suggest that alpha(1A)-ARs may be a useful therapeutic target for the treatment of depression.
BACKGROUND: Prior work demonstrated that female rats (but not their male littermates) exposed to methamphetamine become hypersensitive to myocardial ischemic injury. Importantly, this sex-dependent effect persists following 30 days of subsequent abstinence from the drug, suggesting that i
t may be mediated by long term changes in gene expression that are not rapidly reversed following discontinuation of methamphetamine use. The goal of the present study was to determine whether methamphetamine induces sex-dependent changes in myocardial gene expression and whether these changes persist following subsequent abstinence from methamphetamine. RESULTS: Methamphetamine induced changes in the myocardial transcriptome were significantly greater in female hearts than male hearts both in terms of the number of genes affected and the magnitude of the changes. The largest changes in female hearts involved genes that regulate the circadian clock (Dbp, Per3, Per2, BMal1, and Npas2) which are known to impact myocardial ischemic injury. These genes were unaffected by methamphetamine in male hearts. All changes in gene expression identified at day 11 returned to baseline by day 30. CONCLUSIONS: These data demonstrate that female rats are more sensitive than males to methamphetamine-induced changes in the myocardial transcriptome and that methamphetamine does not induce changes in myocardial transcription that persist long term after exposure to the drug has been discontinued.
BACKGROUND: Neuropeptide S Receptor 1 ( NPSR1) and Retinoid Acid Receptor-Related Orphan Receptor Alpha (RORA ) interact biologically, are both known candidate genes for asthma, and are involved in controlling circadian rhythm. Thus, we assessed (1) w
hether interactions between RORA and NPSR1 specifically affect the nocturnal asthma phenotype and (2) how this may differ from other asthma phenotypes. METHODS: Interaction effects between 24 single-nucleotide polymorphisms (SNPs) in RORA and 35 SNPs in NPSR1 on asthma and nocturnal asthma symptoms were determined in 1432 subjects (763 asthmatics [192 with nocturnal asthma symptoms]; 669 controls) from the Multicenter Asthma Genetic in Childhood/International Study of Asthma and Allergies in Childhood studies. The results were validated and extended in children from the Manchester Asthma and Allergy Study (N = 723) and the Children Allergy Milieu Stockholm and Epidemiological cohort (N = 1646). RESULTS: RORA* NPSR1 interactions seemed to affect both asthma and nocturnal asthma. In stratified analyses, however, interactions mainly affected nocturnal asthma and less so asthma without nocturnal symptoms or asthma severity. Results were replicated in two independent cohorts and seemed to remain constant over time throughout youth. CONCLUSION: RORA* NPSR1 interactions appear to be involved in mechanisms specific for nocturnal asthma. In contrast to previous studies focusing on the role of beta 2 receptor polymorphisms in nocturnal asthma as a feature of asthma control or severity in general, our data suggest that changes in circadian rhythm control are associated with nighttime asthma symptoms.
Bai Z, etal., FEBS Open Bio. 2022 Oct;12(10):1814-1827. doi: 10.1002/2211-5463.13469. Epub 2022 Aug 7.
The mortality rate of patients with coronary artery disease (CAD) increases year by year, and the age of onset is decreasing, primarily because of the lack of an efficient and convenient diagnostic method for CAD. In the present study, we aimed to detect CAD-correlated biomarkers and the regulatory
pathways involved through weighted co-expression network analysis. The microarray data originated from 93 CAD patients and 48 controls within the Gene Expression Omnibus (GEO) database. The gene network was implemented by weighted gene co-expression network analysis, and the genes were observed to fall into a range of modules. We took the intersection of genes in the modules most correlated with CAD with the differentially expressed genes of CAD, which were identified by applying the limma package. Lasso regression and support vector machine recursive feature elimination algorithms were used to determine CAD candidate signature genes. The biomarkers for diagnosing CAD were detected by validating candidate signature gene diagnostic capabilities (receiver operating characteristic curves) based on data sets from GEO. Three modules were selected, and 26 vital genes were identified. Eight of these genes were reported as the optimal candidate features in terms of CAD diagnosis. Through receiver operating characteristic curve analysis, we identified three genes (ERCC5, HES6 and RORA; area under the curve > 0.8) capable of distinguishing CAD from the control, and observed that these genes are correlated with the immune response. In summary, ERCC5, HES6 and RORA may have potential for diagnosis of CAD.
Asthma and allergy affect hundreds of millions of people from childhood to old age. In most of them, the inflammatory process of respiratory allergies involves the participation of type 2 cytokines, derived from T helper-2 (Th2)-cell, and Group 2 Innate Lymphoid (ILC2) Cells. An efficient memory Th2
cell response is dependent on IL-13 produced by ILC2s, causing allergic lung inflammation and elevated serum levels of immunoglobulin E. ILC2 cells are derived from common lymphoid progenitors and their growing depends on the transcription factor RORA. The aim of this work was to identify genetic variants in RORA associated with asthma phenotypes and allergy markers. Genomic DNA samples of 1246 individuals participating from Social Changes Asthma and Allergy in Latin America Program (SCAALA) have been genotyped using Illumina Human 2.5 Omni Beadchip. Logistics regressions have been performed to analyze the association among RORA variants and asthma, skin prick tests (SPT), specific IgE and type 2 cytokine production. Twelve single nucleotide variants (SNVs) were significantly associated with atopy (P < 0.01), in which four of them, rs10162630, rs17191519, rs17270243, and rs55796775 and their haplotypes were strongly and positively associated (P < 0.001). Furthermore, these variants increased the RORA gene expression in silico analysis. Other SNVs in RORA were associated with allergy markers, atopic and non-atopic asthma. Therefore, it is believed that variants in RORA gene may influence immunologic features of asthma and allergies and could be possible targets for future treatment of allergic diseases.
Maglione JE, etal., Am J Geriatr Psychiatry. 2015 Oct;23(10):1075-87. doi: 10.1016/j.jagp.2015.03.002. Epub 2015 Mar 13.
BACKGROUND: Depressive symptoms are common in older adults and associated with poor outcomes. Although circadian genes have been implicated in depression, the relationship between circadian genes and depressive symptoms in older adults is unclear. METHODS: A cross-sectional genetic association study
of 529 single nucleotide polymorphisms (SNPs) representing 30 candidate circadian genes was performed in two population-based cohorts: the Osteoporotic Fractures in Men Study (MrOS; N=270, age: 76.58+/-5.61 years) and the Study of Osteoporotic Fractures (SOF) in women (N=1740, 84.05+/-3.53 years) and a meta-analysis was performed. Depressive symptoms were assessed with the Geriatric Depression Scale categorizing participants as having none-few symptoms (0-2), some depressive symptoms (>2 to <6), or many depressive symptoms (>/=6). RESULTS: We found associations meeting multiple testing criteria for significance between the PER3 intronic SNP rs12137927 and decreased odds of reporting "some depressive symptoms" in the SOF sample (odds ratio [OR]: 0.61, 95% confidence interval [CI]: 0.48-0.78, df=1, Wald chi2=-4.04, p=0.000054) and the meta-analysis (OR: 0.61, CI: 0.48-0.78, z=-4.04, p=0.000054) and between the PER3 intronic SNPs rs228644 (OR: 0.74, CI: 0.63-0.86, z=3.82, p=0.00013) and rs228682 (OR: 0.74, CI: 0.86-0.63, z=3.81, p=0.00014) and decreased odds of reporting "some depressive symptoms" in the meta-analysis compared to endorsing none-few depressive symptoms. The RORA intronic SNP rs11632098 was associated with greater odds of reporting "many depressive symptoms" (OR: 2.16, CI: 1.45-3.23, df=1, Wald chi2=3.76, p=0.000168) in the men. In the meta-analysis the association was attenuated and nominally significant (OR: 1.63, CI: 1.24-2.16, z=3.45, p=0.00056). CONCLUSION: PER3 and RORA may play important roles in the development of depressive symptoms in older adults.
Cai X, etal., Ann Hum Genet. 2018 May;82(3):158-164. doi: 10.1111/ahg.12238. Epub 2017 Dec 28.
Asthma is a common, heterogeneous chronic respiratory disease characterized by chronic inflammation of the airway, airway hyperreactivity, and airway remodeling. The RAR-related orphan receptor A (RORA) gene has been identified for the pathogenesis of asthma. Th
e purpose of this research was to investigate the relationship between RORA gene polymorphisms and asthma susceptibility in the Chinese Zhuang population. This was a case-control study including 231 children with asthma and 343 healthy controls. The RORA gene polymorphisms were measured by the polymerase chain reaction-ligase detection reaction genotyping assays and confirmed by sequencing. The distribution of the genotype frequencies of the RORA rs11071559 C>T was significantly different in the group of cases and the healthy children (P < 0.05). By haplotype analyses, the haplotype TT (rs7164773/rs11071559) was statistically significant between asthmatics and nonasthmatics, but the association was not significant after correction for multiple comparisons. Our results provided evidence that the RORA rs11071559C>T polymorphism was associated with an elevated susceptibility to pediatric asthma in the Chinese Zhuang population.
Guissart C, etal., Am J Hum Genet. 2018 May 3;102(5):744-759. doi: 10.1016/j.ajhg.2018.02.021. Epub 2018 Apr 12.
RORα, the RAR-related orphan nuclear receptor alpha, is essential for cerebellar development. The spontaneous mutant mouse staggerer, with an ataxic gait caused by neurodegeneration of cerebellar Purkinje cells, was discovered two decades ago to result from homozygous intragenic Rora
ont-weight:700;'>Rora deletions. However, RORA mutations were hitherto undocumented in humans. Through a multi-centric collaboration, we identified three copy-number variant deletions (two de novo and one dominantly inherited in three generations), one de novo disrupting duplication, and nine de novo point mutations (three truncating, one canonical splice site, and five missense mutations) involving RORA in 16 individuals from 13 families with variable neurodevelopmental delay and intellectual disability (ID)-associated autistic features, cerebellar ataxia, and epilepsy. Consistent with the human and mouse data, disruption of the D. rerio ortholog, roraa, causes significant reduction in the size of the developing cerebellum. Systematic in vivo complementation studies showed that, whereas wild-type human RORA mRNA could complement the cerebellar pathology, missense variants had two distinct pathogenic mechanisms of either haploinsufficiency or a dominant toxic effect according to their localization in the ligand-binding or DNA-binding domains, respectively. This dichotomous direction of effect is likely relevant to the phenotype in humans: individuals with loss-of-function variants leading to haploinsufficiency show ID with autistic features, while individuals with de novo dominant toxic variants present with ID, ataxia, and cerebellar atrophy. Our combined genetic and functional data highlight the complex mutational landscape at the human RORA locus and suggest that dual mutational effects likely determine phenotypic outcome.
Apuhan T, etal., Eur Rev Med Pharmacol Sci. 2013 Oct;17(19):2680-3.
OBJECTIVES: Nasal polyposis is chronic inflammatory disease of the nasal mucosa of the nose and sinuses, often associated with chronic non-allergic rhinitis, aspirin intolerance and non-allergic asthma. The etiology of nasal polyposis is unknown. Multiple factors contribute to the develop
ment of nasal polyps including genetic predisposition. PATIENTS AND METHODS: This study was conducted on patients applied due to nasal polyps. Blood samples were collected peripheral vein and stored at 4°C until analysis for DNA extraction. Genomic DNA was extracted from peripheral blood by a standard method, samples were studied in real time PCR. All patients were evaluated about the possible association of DSG1 (rs7236477-G, 96 rxn), DSG3 (rs1941184-C, 96 rxn), PDE4D (rs1588265) and RORA (rs11071559) gene. RESULTS: 32 patients (17 male, 15 female) with nasal polyposis were included to the study. The mean age was 34.9 ± 17.7 years, ranging between 18 and 55 years. Control group was consisted with 50 healthy volunteers without a history of nasal polyp. DSG1, DSG3 and RORA values of the study group were not statistically different from control group (p > 0.05). PDE4D values of the study group were significantly different from control group (p < 0.05). CONCLUSIONS: Multiple factors contribute to the pathogenesis of nasal polyps including genetic predisposition. The PDE4D family has gained interest in the complex pathogenesis of nasal polyposis. This is likely linked to the mucosal inflammatory response.
Retinoid acid receptor-related Orphan Receptor Alpha (RORA) was recently identified as a susceptibility gene for asthma in a genome-wide association study. To investigate the impact of RORA on asthma susceptibility, we perfo
rmed a genetic association study between RORA single nucleotide polymorphisms (SNPs) in the vicinity of the asthma-associated SNP (rs11071559) and asthma-related traits. Because the regulatory region of a previously implicated asthma susceptibility gene, Neuropeptide S receptor 1 (NPSR1), has predicted elements for RORA binding, we hypothesized that RORA may interact biologically and genetically with NPSR1. 37 RORA SNPs and eight NPSR1 SNPs were genotyped in the Swedish birth cohort BAMSE (2033 children) and the European cross-sectional PARSIFAL study (1120 children). Seven RORA SNPs confined into a 49 kb region were significantly associated with physician-diagnosed childhood asthma. The most significant association with rs7164773 (T/C) was driven by the CC genotype in asthma cases (OR = 2.0, 95%CI 1.36-2.93, p = 0.0003 in BAMSE; and 1.61, 1.18-2.19, p = 0.002 in the combined BAMSE-PARSIFAL datasets, respectively), and strikingly, the risk effect was dependent on the Gln344Arg mutation in NPSR1. In cell models, stimulation of NPSR1 activated a pathway including RORA and other circadian clock genes. Over-expression of RORA decreased NPSR1 promoter activity further suggesting a regulatory loop between these genes. In addition, Rora mRNA expression was lower in the lung tissue of Npsr1 deficient mice compared to wildtype littermates during the early hours of the light period. We conclude that RORA SNPs are associated with childhood asthma and show epistasis with NPSR1, and the interaction between RORA and NPSR1 may be of biological relevance. Combinations of common susceptibility alleles and less common functional polymorphisms may modify the joint risk effects on asthma susceptibility.
Cai X, etal., Mol Med Rep. 2020 Dec;22(6):4579-4588. doi: 10.3892/mmr.2020.11558. Epub 2020 Oct 2.
FGD5 antisense RNA 1 (FGD5‑AS1) is a long non‑coding RNA in acute myocardial infarction (AMI), which is primarily caused by myocardial ischemia‑hypoxia. Retinoid acid receptor‑related orphan receptor α (RORA) is a key protector in maintaining heart functio
n. However, the roles of FGD5‑AS1 and RORA in AMI have not previously been elucidated. The present study investigated the effect and mechanism of FGD5‑AS1 and RORA in human cardiomyocyte AC16 cells under hypoxia. Reverse transcription‑quantitative PCR and western blotting demonstrated that FGD5‑AS1 and RORA were downregulated in the serum of patients with AMI and hypoxia‑challenged AC16 cells. Functional experiments were performed via assays, flow cytometry and western blotting. In response to hypoxia, superoxide dismutase (SOD) activity was inhibited, but apoptosis rate and levels of reactive oxygen species and malondialdehyde were promoted in AC16 cells, accompanied by increased Bax and cleaved caspase‑3 expression levels, and decreased SOD2 and glutathione peroxidase 1 expression levels. However, hypoxia‑induced oxidative stress and apoptosis in AC16 cells were attenuated by ectopic expression of FGD5‑AS1 or RORA. Moreover, silencing RORA counteracted the suppressive role of FGD5‑AS1 overexpression in hypoxic injury. FGD5‑AS1 controlled RORA expression levels via microRNA‑195‑5p (miR‑195), as confirmed by dual‑luciferase reporter and RNA pull‑down assays. Consistently, miR‑195 knockdown suppressed hypoxia‑induced oxidative stress and apoptosis in AC16 cells, which was abrogated by downregulating FGD5‑AS1 or RORA. In conclusion, FGD5‑AS1 modulated hypoxic injury in human cardiomyocytes partially via the miR‑195/RORA axis, suggesting FGD5‑AS1 as a potential target in interfering with the progression of AMI.
Xiao W, etal., Cell Death Dis. 2022 May 3;13(5):427. doi: 10.1038/s41419-022-04857-y.
Lung adenocarcinoma (LUAD) represents the most frequently diagnosed histological subtype of non-small cell lung cancer with the highest mortality worldwide. Transcriptional dysregulation is a hallmark of nearly all kinds of cancers. In the study, we identified that the POU domain, class 6, transcrip
tion factor 1 (POU6F1), a member of the POU family of transcription factors, was closely associated with tumor stage and death in LUAD. We revealed that POU6F1 was downregulated in LUAD tissues and downregulated POU6F1 was predictive of an unfavorable prognosis in LUAD patients. In vitro assays, including CCK8, soft agar, transwell, clone formation, wound-healing assay, and nude mouse xenograft model all revealed that POU6F1 inhibited the growth and invasion of LUAD cells. Mechanistically, POU6F1 bound and stabilized retinoid-related orphan receptor alpha (RORA) to exert the transcriptional inhibition of hypoxia-inducible factor 1-alpha (HIF1A) and alter the expression of HIF1A signaling pathway-associated genes, including ENO1, PDK1, and PRKCB, thereby leading to the suppression of LUAD cells. Collectively, these results demonstrated the suppressive role of POU6F1/RORA in the progression of LUAD and may potentially be used as a target for the treatment of LUAD.
Lian P, etal., Int Immunopharmacol. 2022 Jul;108:108874. doi: 10.1016/j.intimp.2022.108874. Epub 2022 May 26.
BACKGROUND: Allergic rhinitis (AR) is the most common inflammatory disorder induced by complex interactions between genetic and environmental factors. Genetic predisposition is the most important factor in the progression of AR. Previous studies have indicated that RORA
t:700;'>RORA is involved in the occurrence of AR. The present study aimed to determine the roles of RORA polymorphisms in AR susceptibility. METHODS: Peripheral blood samples were collected from 990 patients with AR and 1004 normal controls. Four single nucleotide polymorphisms (SNPs) in the RORA gene were detected by MassARRAY iPLEX platform. The associations of RORA polymorphisms with AR risk were determined according to logistic regression analysis. We further evaluated the impact of SNP-SNP interaction on AR risk using multifactor dimensionality reduction (MDR) method. RESULTS: Our results showed that rs10519067 (OR 0.38, p = 0.021), rs10519068 (OR 0.45, p = 0.030), and rs11071559 (OR 0.83, p = 0.032) were significantly related to a decreased susceptibility to AR. Stratified analyses found that rs10519067 (OR 0.71, p = 0.046) and rs10519068 (OR 0.63, p = 0.010) could decrease the risk of AR in males. Rs10519068 (OR 0.73, p = 0.022), rs11071559 (OR 0.77, p = 0.041), and rs9302216 (OR 0.38, p = 0.017) significantly reduced the susceptibility to AR in people aged > 43 years. Furthermore, it was found that rs10519067 (OR 0.29, p = 0.032), rs10519068 (OR 0.72, p = 0.013), and rs11071559 (OR 0.36, p = 0.015) had a protective effect on AR patients with BMI <= 24 kg/m2. MDR revealed that the combination of rs10519067, rs10519068, rs11071559, and rs9302216 was the best predictive model for AR. CONCLUSION: Our study suggests that RORA polymorphisms may play a protective role in the development of AR.
Du H, etal., Transl Lung Cancer Res. 2022 May;11(5):890-901. doi: 10.21037/tlcr-22-104.
BACKGROUND: Lymphocyte activation is part of a complex microenvironment that affects the development and progression of solid tumors. The present study analyzed the associations between genetic variants in lymphocyte activation-related genes and survival of patients with non-small cell lu
ng cancer (NSCLC). METHODS: Our study evaluated the associations of 14,400 (1,599 genotyped and 12,801 imputed) single-nucleotide polymorphisms (SNPs) in 176 lymphocyte activation pathway-related genes with survival of 1,185 NSCLC patients in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial and validated the results in another independent dataset of 984 NSCLC patients from the Harvard Lung Cancer Susceptibility (HLCS) trial. RESULTS: Multivariable Cox proportional hazards regression analyses identified two distinct and possibly functional variants in forkhead box P1 (FOXP1; rs2568847 G>C) and RAR-related orphan receptor A (RORA; rs922782 T>G) that were significantly and independently associated with overall survival (OS) [adjusted hazards ratios (HRs) of 1.21 and 0.82, respectively; 95% confidence intervals (CI), 1.11 to 1.32 and 0.76 to 0.88, respectively; P=5.38×10-6 and 2.68×10-2, respectively]. Combined analysis of the unfavorable genotypes showed a significant correlation with both OS and disease-specific survival (DSS) in patients with NSCLC patients from PLCO trial (both Ptrend<0.0001). Further expression quantitative trait loci (eQTL) analysis using RORA mRNA expression and genotype data in the 1000 Genomes Project demonstrated that the RORA rs922782 G allele predicted mRNA expression levels. CONCLUSIONS: Genetic variants in FOXP1 and RORA of the lymphocyte activation pathway may be promising predictors of NSCLC survival. The RORA rs922782 G allele may predict NSCLC survival, possibly by controlling RORA mRNA expression.
He B, etal., J Pineal Res. 2016 Apr;60(3):313-26. doi: 10.1111/jpi.12312. Epub 2016 Feb 16.
Circadian rhythm disruption or decrease in levels of circadian hormones such as melatonin increases ischemic heart disease risk. The nuclear melatonin receptors RORs are pivotally involved in circadian rhythm regulation and melatonin effects mediation. However, the functional roles of RORs in the he
art have never been investigated and were therefore the subject of this study on myocardial ischemia/reperfusion (MI/R) injury pathogenesis. RORa and ROR¿ subtypes were detected in the adult mouse heart, and RORa but not ROR¿ was downregulated after MI/R. To determine the pathological consequence of MI/R-induced reduction of RORa, we subjected RORa-deficient staggerer mice and wild-type (WT) littermates to MI/R injury, resulting in significantly increased myocardial infarct size, myocardial apoptosis and exacerbated contractile dysfunction in the former. Mechanistically, RORa deficiency promoted MI/R-induced endoplasmic reticulum stress, mitochondrial impairments, and autophagy dysfunction. Moreover, RORa deficiency augmented MI/R-induced oxidative/nitrative stress. Given the emerging evidence of RORa as an essential melatonin effects mediator, we further investigated the RORa roles in melatonin-exerted cardioprotection, in particular against MI/R injury, which was significantly attenuated in RORa-deficient mice, but negligibly affected by cardiac-specific silencing of ROR¿. Finally, to determine cell type-specific effects of RORa, we generated mice with cardiomyocyte-specific RORa overexpression and they were less vulnerable to MI/R injury. In summary, our study provides the first direct evidence that the nuclear melatonin receptor RORa is a novel endogenous protective receptor against MI/R injury and an important mediator of melatonin-exerted cardioprotection; melatonin-RORa axis signaling thus appears important in protection against ischemic heart injury.
Sun Y, etal., Proc Natl Acad Sci U S A. 2015 Aug 18;112(33):10401-6. doi: 10.1073/pnas.1504387112. Epub 2015 Aug 4.
Pathologic ocular angiogenesis is a leading cause of blindness, influenced by both dysregulated lipid metabolism and inflammation. Retinoic-acid-receptor-related orphan receptor alpha (RORalpha) is a lipid-sensing nuclear receptor with diverse biologic function including regulation of lipid metaboli
sm and inflammation; however, its role in pathologic retinal angiogenesis remains poorly understood. Using a mouse model of oxygen-induced proliferative retinopathy, we showed that RORalpha expression was significantly increased and genetic deficiency of RORalpha substantially suppressed pathologic retinal neovascularization. Loss of RORalpha led to decreased levels of proinflammatory cytokines and increased levels of antiinflammatory cytokines in retinopathy. RORalpha directly suppressed the gene transcription of suppressors of cytokine signaling 3 (SOCS3), a critical negative regulator of inflammation. Inhibition of SOCS3 abolished the antiinflammatory and vasoprotective effects of RORalpha deficiency in vitro and in vivo. Moreover, treatment with a RORalpha inverse agonist SR1001 effectively protected against pathologic neovascularization in both oxygen-induced retinopathy and another angiogenic model of very-low-density lipoprotein receptor (Vldlr)-deficient (Vldlr (-/-) ) mice with spontaneous subretinal neovascularization, whereas a RORalpha agonist worsened oxygen-induced retinopathy. Our data demonstrate that RORalpha is a novel regulator of pathologic retinal neovascularization, and RORalpha inhibition may represent a new way to treat ocular neovascularization.
It is widely known that there is an increase in the inflammatory responses and oxidative stress in temporal lobe epilepsy (TLE). Further, the seizures follow a circadian rhythmicity. Retinoic acid receptor-related orphan receptor alpha (RORalpha) is related to anti-inflammatory and antioxidant enzy
me expression and is part of the machinery of the biological clock and circadian rhythms. However, the participation of RORalpha in this neurological disorder has not been studied. The aim of this study was to evaluate the RORalpha mRNA and protein content profiles in the hippocampus of rats submitted to a pilocarpine-induced epilepsy model at different time points throughout the 24-h light-dark cycle analyzing the influence of the circadian rhythm in the expression pattern during the acute, silent, and chronic phases of the experimental model. Real-time PCR and immunohistochemistry results showed that RORalpha mRNA and protein expressions were globally reduced in both acute and silent phases of the pilocarpine model. However, 60days after the pilocarpine-induced status epilepticus (chronic phase), the mRNA expression was similar to the control except for the time point 3h after the lights were turned off, and no differences were found in immunohistochemistry. Our results indicate that the status epilepticus induced by pilocarpine is able to change the expression and daily variation of RORalpha in the rat hippocampal area during the acute and silent phases. These findings enhance our understanding of the circadian pattern present in seizures as well as facilitate strategies for the treatment of seizures.
Itoh Y, etal., Biochem Biophys Res Commun. 2016 Mar 9. pii: S0006-291X(16)30330-8. doi: 10.1016/j.bbrc.2016.03.016.
Hepatic gluconeogenic programs are regulated by a variety of signaling cascades. Glucagon-cAMP signaling is the main initiator of the gluconeogenic programs, including glucose-6-phosphatase catalytic subunit (G6pc) gene expression. Pterosin B, an ingredient in Pteridium aquilinum, inhibits salt-ind
ucible kinase 3 signaling that represses cAMP-response element-binding protein regulated transcription coactivator 2, an inducer of gluconeogenic programs. As the results, pterosin B promotes G6pc expression even in the absence of cAMP. In this work, however, we noticed that once cAMP signaling was initiated, pterosin B became a strong repressor of G6pc expression. The search for associated transcription factors for pterosin B actions revealed that retinoic acid receptor-related orphan receptor alpha-steroid receptor coactivator 2 (RORalpha-SRC2) complex on the G6pc promoter was the target. Meanwhile, pterosin B impaired the oxidation-reduction cycle of coenzyme Q in mitochondrial oxidative phosphorylation (OXPHOS); and antimycin A, an inhibitor of coenzyme Q: cytochrome c-oxidoreductase (termed mitochondrial complex III), also mimicked pterosin B actions on RORalpha-SRC2 signaling. Although other respiratory toxins (rotenone and oligomycin) also suppressed G6pc expression accompanied by lowered ATP levels following the activation of AMP-activated kinase, minimal or no effect of these other toxins on RORalpha-SRC2 activity was observed. These results suggested that individual components in OXPHOS differentially linked to different transcriptional machineries for hepatic gluconeogenic programs, and the RORalpha-SRC2 complex acted as a sensor for oxidation-reduction cycle of coenzyme Q and regulated G6Pc expression. This was a site disrupted by pterosin B in gluconeogenic programs.
Han YH, etal., Antioxid Redox Signal. 2014 Nov 20;21(15):2083-94. doi: 10.1089/ars.2013.5655. Epub 2014 Apr 10.
AIMS: Increased hepatic oxidative stress and inflammation is the main cause of exacerbating nonalcoholic steatohepatitis (NASH). Retinoic acid-related orphan receptor alpha (RORalpha) regulates diverse target genes associated with lipid metabolism, and its expression level is low in the liver of pat
ients with NASH. Here, we investigated the role of RORalpha in regulating hepatic oxidative stress and inflammation. RESULTS: First, cholesterol sulfate (CS), an agonist of RORalpha, lowered oxidative stress that was induced by 1.5 mM oleic acid in the primary cultures of hepatocytes. Second, exogenously introduced RORalpha or CS treatment induced the mRNA level of antioxidant enzymes, superoxide dismutase 2 (SOD2) and glutathione peroxidase 1 (GPx1), through the RORalpha response elements located in the upstream promoters of Sod2 and Gpx1. Third, RORalpha significantly decreased reactive oxygen species levels and mRNA levels of tumor necrosis factor alpha (TNFalpha) and interleukin-1beta that were induced by lipopolysaccharide or TNFalpha in Kupffer cells. Finally, the administration of JC1-40 decreased the signs of liver injury, lipid peroxidation, and inflammation in the MCD diet-induced NASH mice. INNOVATION AND CONCLUSION: We showed for the first time that RORalpha and its ligands protect NASH in mice by reducing hepatic oxidative stress and inflammation. Further, the molecular mechanism of the protective function of RORalpha against oxidative stress in the liver was revealed. These findings may offer a rationale for developing therapeutic strategies against NASH using RORalpha ligands.