Abnormal accumulation of autophagosomes in skeletal muscle tissue.
Comment:
Autophagy (self-eating) is a process of lysosomal degradation of long-lived proteins and damaged organelles. In macroautophagy (hereafter referred to as autophagy), double-membrane vesicles known as autophagosomes sequester cytoplasm and damaged organelles. The autophagosomes fuse with endosomes, giving rise to amphisomes, followed by fusion with lysosomes where degradation of autophagosomal contents is completed. Autophagy is a critical survival mechanism under conditions of nutrient deprivation and appears to play a role in basal protein turnover as well. Under normal conditions, autophagosomes and amphisomes are quickly degraded by lysosomes, and their content is recycled. In certain pathological states, significant accumulation of autophagosomes is observed.