SIRT1-PINK1-Parkin axis orchestrated mitophagy and renal repair by dapagliflozin in diabetic nephropathy

Background: Mitochondrial dysfunction caused by metabolic stress is a key part of diabetic nephropathy. Dapagliflozin exerts significant hypoglycemic and nephroprotective effects; however, the precise mechanisms underlying its renoprotective actions remain to be fully elucidated. Objective: This study aimed to elucidate the molecular mechanisms through which dapagliflozin mitigates diabetic nephropathy (DN), with particular emphasis on its regulatory role in the Sirt1-Pink1-Parkin axis and the restoration of mitochondrial homeostasis via mitophagy. Methods: Rats were fed a high-fat/high-sugar diet and streptozotocin. They were then divided into groups of various treatments. In vitro, high glucose-induced NRK-52E cell injury was treated with dapagliflozin. Evaluations included renal histopathology, urinary biomarkers, apoptosis, reactive oxygen species, mitochondrial membrane potential, and Sirt1/Pink1/Parkin pathway activation. Results: Dapagliflozin exerted significant protective effects against streptozotocin-induced diabetic nephropathy. Dapagliflozin treatment in vitro restored mitochondrial membrane potential and reduced ROS levels in high glucose-induced NRK-52E cells. High glucose exposure markedly upregulated the expression of mitochondria-associated apoptotic proteins in NRK-52E cells, which was reduced by dapagliflozin. This study revealed that Sirt1/Pink1/Parkin-mediated mitophagy was suppressed in DN and high glucose-induced NRK-52E cells but was activated following dapagliflozin treatment. Conclusion: Our findings demonstrate that dapagliflozin modulates Sirt1/Pink1/Parkin-mediated mitochondrial autophagy and effectively restores mitochondrial homeostasis in diabetic nephropathy. Modulating mitochondrial autophagy through this pathway may serve as a promising therapeutic strategy for diabetic nephropathy.