Objective: To investigate nephroprotective potential of Meristotropis xanthioides (M. xanthioides) extract against ethanol-induced nephrotoxicity in Wistar rats, and also its total phenolics content, antioxidant and antibacterial activities. Methods: Total phenol and flavonoid amounts of the leaf and stem extracts were determined by Folin–Ciocalteu and aluminum chloride reagents, respectively. Antioxidant and antibacterial activities of the extracts were investigated by 2,2-diphenyl-1- picrylhydrazyl radical scavenging and disc diffusion methods, respectively. In addition, protective potential of the leaf extract against ethanol-induced nephrotoxicity was studied by histological and biochemical analyses. Results: Obtained results indicated high total phenol [(10.26 ± 0.46) mg GAE/g of dry extract] and flavonoid [(3.63 ± 0.62) mg QE/g of dry extract] amounts in the leaf extract. The leaf and stem extracts possessed stronger antioxidant activity [IC50: (0.119 ± 0.006) mg/mL and IC50: (0.133 ± 0.009 mg/mL)] than that of ascorbic acid [IC50: (0.142 ± 0.002) mg/mL]. Also, the extracts showed good antibacterial activity against the most of bacteria taken in this research, especially Gram-positive ones. Histological examinations revealed tissue injury in the kidney of rats treated with ethanol. Results from biochemical assays showed reduction in total protein content and also in superoxide dismutase activity. In addition, remarkable increased levels (P < 0.05) of H2O2 and malondialdehyde were found in ethanol-treated rats in comparison to control group. However, these injuries were significantly improved in rats treated by M. xanthioides leaf extract. Conclusions: Results from present study demonstrates strong pharmaceutical potential of M. xanthioides extract to apply as a new drug supplement.
