Vitamin E and Hippophea rhamnoides L. extract reduce nicotine‐induced oxidative stress in rat heart

The effects of vitamin E and Hippophea rhamnoides L. extract (HRe‐1) on nicotine‐induced oxidative stress in rat heart were investigated. There were eight rats per group and supplementation period was 3 weeks. The groups were: nicotine 0.5 mg kg^?1day^?1, intraperitoneal (i.p.)]; nicotine plus vitamin E 75 mg kg^?1day^?1, intragastric (i.g.)]; nicotine plus HRe‐1 (250 mg kg^?1day^?1, i.g.); and the control group (receiving only vehicles). Nicotine increased the malondialdehyde level, which was prevented by both vitamin E and HRe‐1. Glutathione peroxidase (GPx) activity in nicotine plus vitamin E supplemented group was higher than the others. Glutathione S‐transferase (GST) activity in nicotine plus HRe‐1 supplemented group was increased compared with the control group. Catalase activity was higher in nicotine group compared with others. GPx activity in nicotine plus vitamin E supplemented group was elevated compared with the others. Total and non‐enzymatic superoxide scavenger activities in nicotine plus vitamin E supplemented group were lower than nicotine plus HRe‐1 supplemented group. Superoxide dismutase (SOD) activity was higher in nicotine plus HRe‐1 supplemented group compared with others. Glutathione reductase activity and nitric oxide level were not affected. Increased SOD and GST activities might have taken part in the prevention of nicotine‐induced oxidative stress in HRe‐1 supplemented group in rat heart. Flavonols such as quercetin, and isorahmnetin, tocopherols such as α‐tocopherol and β‐tocopherol and carotenoids such as α‐carotene and β‐carotene, reported to be present in H. rhamnoides L. extracts may be responsible for the antioxidant effects of this plant extract. Copyright © 2010 John Wiley & Sons, Ltd.