Celastrol ameliorates cisplatin nephrotoxicity by inhibiting NF-κB and improving mitochondrial function

BACKGROUND: Celastrol is an active ingredient of Chinese medicine Tripterygium wilfordii which is clinically used to treat the immune diseases. Currently, celastrol is documented as a potent agent for treating cancer and inflammatory disorders. This study was to investigate the effect of celastrol on cisplatin nephrotoxicity and the underlying mechanism. METHODS: Male C57BL/6 mice were treated with cisplatin (20 mg/kg) with or without celastrol treatment (1 and 2 mg/kg/day). In vitro, human proximal tubule epithelial cell line (HK−2) and mouse renal tubule epithelial cells (RTECs) were treated with cisplatin (5 μg/mL) with or without celastrol administration. Then renal injury and cell damage were evaluated. FINDINGS: In vivo, after celastrol treatment, cisplatin-induced kidney injury was significantly ameliorated as shown by the improvement of renal function (BUN, serum creatinine, and cystatin C), kidney morphology (PAS staining) and oxidative stress (MDA) and the suppression of renal tubular injury markers of KIM-1 and NGAL. Meanwhile, the renal apoptosis and inflammation induced by cisplatin were also strikingly attenuated in celastrol-treated mice. In vitro, celastrol treatment markedly inhibited cisplatin-induced renal tubular cell apoptosis, suppressed NF-κB activation, and improved mitochondrial function evidenced by the restored mtDNA copy number, mitochondrial membrane potential, and OXPHOS activity in cisplatin-treated renal tubular epithelial cells. INTERPRETATION: This work suggested that celastrol could protect against cisplatin-induced acute kidney injury possibly through suppressing NF-κB and improving mitochondrial function. FUND: The National Natural Science Foundation of China, National Key Research and Development Program, and Natural Science Foundation of Jiangsu Province.