标题：23-Hydroxytormentic Acid and Niga-Ichgoside F1 Isolated from Rubus coreanus Attenuate Cisplatin-Induced Cytotoxicity by Reducing Oxidative Stress in Renal Epithelial LLC-PK1 Cells
摘要：The unripe fruits of Rubus coreanus (Rosaceae) are used in traditional Chinese medicine to relieve kidney dysfunction. In the present study, we evaluated the protective effects of the triterpenoid glycoside niga-ichigoside F1 (NIF1) and of its aglycone 23-hydroxytormentic acid (23-HTA) isolated from the unripe fruits of Rubus coreanus (Rosaceae) against cisplatin-induced cytotoxicity in renal epithelial LLC-PK1 cells. Pretreating LLC-PK1 cells with 23-HTA or NIF1 was found to prevent cisplatin-induced cytotoxicity and apoptosis. In addition, 23-HTA or NIF1 pretreatment significantly improved the changes associated with cisplatin toxicity by increasing levels of glutathione (GSH) and decreasing levels of malondialdehyde (MDA) and reactive oxygen species (ROS). The activity of antioxidant enzymes including catalase (CAT) and superoxide dismutase (SOD) was significantly lower in cisplatin-treated LL-PK1 cells, and 23-HTA or NIF1 treatment notably increased the these enzyme activity and protein and mRNA levels of CAT and manganese SOD (MnSOD). Moreover, cisplatin caused a significant decrease in nuclear levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and pretreatment with 23-HTA or NIF1 significantly suppressed the cisplatin-induced translocation of Nrf2 in LLC-PK1 cells. Taken together, these results suggest that 23-HTA ameliorates cisplatin-induced toxicity via modulation of antioxidant enzymes through activation of Nrf2 in LLC-PK1 cells.
