Effects?of?Astragalus?Polysaccharide?on?Cisplatin-induced?Renal?Injury?and?its?Mechanism

Objective Cisplatin is a commonly used chemotherapeutic drug,but its clinical application is limited by its nephrotoxicity.Astragalus Polysaccharides(APS)is an effective component extracted from Astragalus membranaceus,which has anti-inflammatory and anti-oxidative effects.In this study,the protective effect and mechanism of Astragalus Polysaccharides were investigated by cisplatin-induced acute kidney injury model in mice and human renal proximal tubular epithelial cells(HK-2 cells).Methods 1.Serum Creatinine(Scr),Blood Urea Nitrogen(BUN)and serum Kim-1 in cisplatin-injected mice and APS-pretreated +cisplatin-injected mice were compared.Kim-1 and Ngal in renal homogens were detected by ELISA.2.TUNEL staining was used to detect apoptosis in kidney tissues of mice and Immunohistochemical used to detect 3-nitrotyrosine(3-NT).ELISA was used to detect the activity of CuZn/Mn-SOD and total glutathione peroxidase(GSH-px)in homogenate of kidney tissues.3.In HK-2 cells treated with cisplatin and APS+cisplatin,CCK-8 assay was used to detect the difference of cell viability.TUNEL was used to detect apoptosis and observe the protective effect of APS at the cell?lar level.4.DCFH-DA flow cytometry and Mito SOX Red fluorescence microscopy were used to detect reactive oxygen species(ROS)in cells and mitochondria in order to study the antioxidant effect of APS.5.Mito Tracker was used to observe mitochondrial morphology;RNA level of mitochondrial fusion-fisson homeostasis-related proteins were analyzed by Real-Time qPCR;flow cytometry detected the opening of mitochondrial membrane permeability transition pore;Westen Blotting detected Cytochrome C release in cytoplasm to studythe protective effect of APS on mitochondria.Res?lts 1.APS can significantly reduce the levels of SCr,BUN and Kim-1 in cisplatin-induced mice,the scores of renal tub?lar injury index and the expression of Kim-1 and Ngal in tissues,reduce the apoptosis of renal tub?lar epithelial cells,protect the activity of CuZn/Mn-SOD and total glutathione peroxidase(GSH-px),and reduce the production of oxidative stress production 3-NT.2.APS can significantly improve cell viability,reduce HK-2 cell apoptosis,reduce ROS aggregation in cell and SOX aggregation in mitochondria induced by cisplatin,reduce oxidative stress injury,reduce mitochondrial breakdown induced by cisplatin,protect mitochondrial morphology,maintain mitochondrial fusion-fisson homeostasis,maintain mitochondrial permeability and reduce mitochondrial Cytochrome C release.Conclusion Astragalus polysaccharide can protect the integrity and function of mitochondria,alleviate oxidative stress injury in mitochondria and cells,thereby reducing the apoptosis of renal tubular epithelial cells,and has protective effect on cisplatin-induced renal injury.