ObjectiveTo investigate the intervention effect and related mechanism of hyperoside on sepsis-associated acute kidney injury (SAKI) in mice. Methods A mouse model of SAKI was established by cecal ligation and puncture (CLP). Sham group, model group, dexamethasone (1 mg/kg) group, hyperoside high-, low-dose (50, 25 mg/kg) groups and hyperoside (50 mg/kg) + nuclear factor erythroid 2-related factor 2 (Nrf2) inhibitor ML385 (30 mg/kg) group were set up. After 7 d of drug intervention, the survival curve of mice was plotted. The levels of renal function, inflammatory factors and oxidative stress were detected. The pathological changes of renal tissue were observed by hematoxylin-eosin (HE) staining. TUNEL staining was used to detect apoptosis in renal tissue cells. Immunohistochemical was used to detect Nrf2 expression in renal tissue. Western blotting was used to detect the expressions of Nrf2, PTEN induced kinase 1 (Pink1) and Parkin proteins in renal tissue. Immunofluorescence was used to detect the co-localization of microtubule associated protein 1 light chain 3B (LC3B) and translocase of the outer mitochondrial membrane 20 (TOMM20) in renal tissue. Lipopolysaccharide (LPS) was used in vitro to induce injury in human tubular epithelial cells (HK-2). After intervention with hyperoside, cell viability, apoptosis and reactive oxygen species levels were detected. Mitochondrial ultrastructure was observed by transmission electron microscopy. Flow cytometry was used to detect mitochondrial membrane potential (MMP) and adenosine triphosphate (ATP) levels to evaluate mitochondrial function. Western blotting was used to detect the expressions of Nrf2, heme oxygenase-1 (HO-1) and mitochondrial autophagy proteins Pink1, Parkin, p62. Results Compared with model group, hyperoside could significantly improve the survival rate of SAKI mice (P < 0.05), alleviate weight loss and renal pathological damage (P < 0.05, 0.01), improve renal function and oxidative stress response (P < 0.05, 0.01), inhibit inflammatory factor levels (P < 0.05, 0.01), up-regulate the expressions of Nrf2, Pink1, Parkin in renal tissue (P < 0.01), and increase the co-ocalization of LC3B and TOMM20 in renal tissue. In vitro experimental results showed that hyperoside (40 μmol/L) could inhibit LPS-induced apoptosis and oxidative stress in HK-2 cells (P < 0.01), increase MMP and ATP levels (P < 0.01), up-regulate Nrf2, HO-1, Pink1, Parkin protein expressions (P < 0.01), down-regulate p62 expression (P < 0.01), promote mitochondrial autophagy, and alleviate mitochondrial damage. In addition, Nrf2 inhibitor ML385 significantly reversed the protective effect of hyperoside on CLP-induced SAKI mice (P < 0.05, 0.01), while weakening hyperoside induced mitochondrial autophagy in HK-2 cells.Conclusion Hypericin may regulate Pink1/Parkin mediated mitochondrial autophagy by activating Nrf2/HO-1 signaling pathway, alleviate mitochondrial dysfunction, alleviate oxidative stress and inflammatory response in SAKI mice, and thus exert renal protective effects.

hyperoside  /  sepsis-associated acute kidney injury  /  mitophagy  /  Nrf2  /  oxidative stress  /  inflammatory response