Abstract: This study attempted to explore the repairing effect of kidney bean sprout polyphenols on D-galactose-induced oxidation and kidney injury in mice. For this purpose, a mouse model of oxidative injury was established by intraperitoneal injection of D-galactose solution, and the mice were gavaged with three different doses of kidney bean sprout polyphenols (20, 40, 60 mg/(kg·d)) or VC for 28 continuous days and then they were sacrificed after administration for the measurement of body weight, kidney coefficient, glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities, and malondialdehyde (MDA), blood urea nitrogen (BUN) and creatinine (CR) concentrations in serum as well as the histopathological examination of kidney section using HE staining. It turned out that all the treatment groups exhibited an elevation in body weight and kidney coefficient compared with the model control group, but no significant difference was observed among the treatment groups (P > 0.05). The middle-dose and high-dose groups showed a significant increase in serum GSH-Px activity (P < 0.05) and a significant reduction in MDA concentration (P < 0.05), which was not observed for the low-dose group. The administration of kidney bean sprout polyphenols resulted in a significant increase in serum SOD activity and a significant decline in BUN (as an indicator of kidney function) and CR levels except at the low dose compared with the model control group (P < 0.05). Histopathological observation showed that the kidney of mice in the model control group was severely damaged, as indicated by enlarged glomeruli and glomerular cysts together with interstitial bleeding and inflammatory cell infiltration. The enlarged glomeruli and glomerular cysts were restored to normal morphology by kidney bean sprout polyphenols, which also mitigated interstitial bleeding and inflammatory cell infiltration. Taken together, kidney bean sprout polyphenols could dose-dependently repair oxidative stress and renal injury in mice.

Key words: kidney bean sprouts polyphenols, D-galactose, oxidative damage, kidney damage, recovery