Rhabdomyolysis-induced acute kidney injury and concomitant apoptosis induction via ROS-mediated ER stress is efficaciously counteracted by epigallocatechin gallate

Abstract

Rhabdomyolysis induced acute kidney injury (RIAKI) is a life-threatening condition responsible for approximately 19-58% of AKI cases worldwide. We performed an intramuscular injection of glycerol (10 mL/kg) in male wistar rats to induce AKI. Epigallocatechin gallate (EGCG) was administered for 3 consecutive days to evaluate its protective effects. We observed significant downregulation in serum creatinine, blood urea nitrogen (BUN) and LDH at different time points on EGCG treatment groups in a dose-dependent manner. Similarly, H&E staining also revealed that EGCG was able to reduce the formation of damaged tubules and tubular necrosis which was prominently spread throughout the kidney tissue of glycerol treatment group. Concomitantly, we observed upregulated inflammation, ER stress and elevated oxidative stress in the glycerol treated group only, which was significantly normalized upon EGCG treatment in both in vitro and in vivo studies. The occurrence of apoptosis in kidney tubules was found to be relatively higher in glycerol treated group and H2O2 treated HEK-293 cells. The results obtained after EGCG treatment revealed a significant decrease in apoptotic cell population, which was further validated by immunofluorescence staining against p53 and comet assay in HEK-293 cells and p53 IHC in kidney tissues. Western blotting also revealed a systemic downregulation of intrinsic mitochondrial apoptotic pathway markers such as bax, bcl-2, pro and cleaved caspase 3, caspase 9 and PARP1. Additionally, the results for flow cytometry analysis and TUNEL assay corroborated apoptotic equilibrium. Conclusively, we reckon EGCG as a multi-therapeutic natural product that can be used the for treatment of AKI.