Effect of total flavonoids of hawthorn leaves on H₂O₂-induced oxidative stress injury of rats

This study was to investigate the role of total flavonoids of hawthorn leaves (TFHL) in oxidative stress injury in rats with diabetic nephropathy (DN). CCK-8 method was used to study the effect of TFHL on the oxidative damage of kidney HK-2 cells induced by H 2 O 2 . 40 Sprague-Dawley (SD) rats with DN induced by streptozotocin were divided into normal saline group and treatment groups treated with TFHL (10, 20, 40 mg/kg). During the 6 weeks of treatment, metabolic parameters such as body weight and fasting blood glucose levels were recorded along with analysis of renal function, levels of renal tissue apoptosis, and fibrosis-related factors. The relative levels of Nrf-2/ARE pathway-related factors in kidney tissue were detected by qPCR and Western blot. 320 μ g/mL TFHL significantly improved the survival rate of HK-2 cells with oxidative damage (92.9%). In treatment group, GPX1, SOD2 and GSH were significantly up-regulated, leading to down-regulation of ROS. In addition, after administration for 6 weeks, TFHL improved the renal function of DN rats and worsened the morphology of nephropathy. They also improved Bcl-2, Nrf-2, NQO-1 and HO-1 levels, and regulated Nrf-2/ARE signaling, thus having a protective effect on the kidney tissue of DN rats. After TFHL acted on kidney cells, the nuclear expression of Nrf-2 protein was significantly increased. TFHL pretreatment up-regulated NQO-1, Nrf-2 and HO-1. Our data showed that in DN rats, TFHL protected renal cells and alleviated renal tissue damage.