Kolaviron Modulates cellular redox status and impairment of membrane protein activities induced by potassium bromate (KBrO3) in rats

Abstract

In this study, we examined the modulatory effects of kolaviron, a biflavonoid from Garcinia kola seeds on the antioxidant defense mechanisms, cellular redox status and oxidative stress in the kidney and liver of rats pretreated with potassium bromate (KBrO3) intragastrically as a single dose of 300 mg kg−1weight for 4 weeks. Treatment of rats with KBrO3resulted in an insignificant difference (P> 0.05) in body weight compared to controls. However, a significant increase in kidney/body weight ratio (P< 0.001) was observed in rats treated with KBrO3while liver/body weight ratio was not affected. KBrO3depressed the activities of superoxide dismutase, glutathione peroxidase and catalase (P< 0.001) in the kidney but not in the liver. Kolaviron (200 mg kg−1body weight) administered three times a week for 4 weeks inhibited the decrease mediated by KBrO3of these enzymes in the kidney by 29, 88 and 45%, respectively. Similarly, kolaviron reduced the KBrO3-induced decrease in the activities of γ -glutamyltransferase and microsomal Ca2+ATPase by 73 and 63% in the kidney. In addition, the extract elicited a 27 and 25% decrease in the KBrO3-induced increase in malondialdehyde and lipid hydroperoxide formation in the kidney. Kolaviron also attenuated the KBrO3-decreased activities of glucose 6-phosphatase, 5 ′ nucleotidase and alkaline phosphatase (membrane enzymes) by 72, 57 and 25% respectively. The results of the present investigation indicate the antioxidative effect of kolaviron, a natural antioxidant, on drug-induced kidney toxicity. Kolaviron may therefore intervene in the cellular redox status and depression of membrane protein activities caused by KBrO3and other environmental carcinogens in the kidney.