Astragaloside IV Protects Against Podocyte Injury by Upregulating Mitophagy via Mfn2/Pink1/Parkin Axis

Background: Podocyte injury is the most important pathological hallmark of kidney diseases. Autophagy is a critical factor that involves podocyte injury. Here, we sought to determine whether Astragaloside IV (AS-IV) was able to improve renal function and reverse podocyte injury through the regulation of autophagy. Methods: Using the Adriamycin (ADR) mice model, cultured immortalized mouse podocytes were exposed to AS-IV. Western blotting, immunofluorescence, and histochemistry were used to analyze markers of autophagy, mitochondrial dysfunction, podocyte apoptosis, and glomerulopathy in the progression of focal segmental glomerular sclerosis. Results: We observed that AS-IV can inhibit podocyte apoptosis, increased reactive oxygen species (ROS) generation, mitochondrial fragmentation, and dysfunction by inducing the Mfn2/Pink1/Parkin mitophagy pathway both in vivo and in vitro. Overexpression of Mfn2 reduced puromycin aminonucleoside (PAN)-induced podocyte injury, while downregulation of Mfn2 expression limited the renal protective effect of AS-IV by regulating mitophagy. Conclusion: AS-IV ameliorates renal function and renal pathological changes in ADR mice and inhibits PAN-induced podocyte injury by directly enhancing Mfn2/Pink1/Parkin-associated autophagy.