Sestrin-2 regulates podocyte mitochondrial dysfunction and apoptosis under high-glucose conditions via AMPK

Diabetic kidney disease (DKD) is a severe form of microangiopathy among diabetic patients, of which podocyte injury is one of the more predominant features. There is increasing evidence to suggest that mitochondrial dysfunction is associated with podocyte injury, thus contributing to the progression of DKD. Initially identified as a p53 target protein, the endogenous antioxidant protein, sestrin-2 (sesn2), has recently attracted attention due to its potential function in various inflammatory diseases. However, the association between sesn2 and podocytes in DKD remains unclear. In the present study, to elucidate the role of sesn2 in podocyte mitochondrial dysfunction, the effects of sesn2 on the regulation of AMP-activated protein kinase (AMPK) were examined in vitro and in vivo. Abnormal mitochondria were found in rats with streptozotocin-induced diabetes, and hyperglycemia downregulated the expression of sesn2. The upregulation of sesn2 increased the level of AMPK phosphorylation, and thus ameliorated mitochondrial dysfunction under high glucose conditions (HG). On the whole, these results suggest that sesn2 is associated with mitochondrial dysfunction in podocytes under HG conditions. In addition, the decreased expression of sesn2 may be a therapeutic target for DKD.