The aim of this study was to investigate whether endurance training reduces exercise-induced oxidative stress in erythrocytes. Male rats (n=54) were divided into trained (n=28) and untrained (n=26) groups. Both groups were further divided equally into two groups where the rats were studied at rest and immediately after exhaustive exercise. Endurance training consisted of treadmill running 1.5 h x day(-1), 5 days a week for 8 weeks, reaching the speed of 2.1 km x h(-1) at the fourth week. For acute exhaustive exercise, graded treadmill running was conducted reaching the speed of 2.1 km x h(-1) at the 95th min, 10% uphill, and was continued until exhaustion. Acute exhaustive exercise increased the erythrocyte malondialdehyde level in sedentary but not in trained rats compared with the corresponding sedentary rest and trained rest groups, respectively. While acute exhaustive exercise decreased the erythrocyte superoxide dismutase activity in sedentary rats, it increased the activity of this enzyme in trained rats. On the other hand, acute exhaustive exercise increased the erythrocyte glutathione peroxidase activity in sedentary rats; however, it did not affect this enzyme activity in trained rats. Erythrocyte glutathione peroxidase activity was higher in trained groups compared with untrained sedentary group. Neither acute exhaustive exercise nor treadmill training affected the erythrocyte total glutathione level. Treadmill training increased the endurance time in trained rats compared with sedentary rats. The results of this study suggest that endurance training may be useful to prevent acute exhaustive exercise-induced oxidative stress in erythrocytes by up-regulating some of the antioxidant enzyme activities and may have implications in exercising humans.

The aim of this study was to determine the effects of Hippophae rhamnoides L. extract (HRe-1) and also vitamin E as a positive control on nicotine-induced oxidative stress in rat blood, specifically alterations in erythrocyte malondialdehyde (MDA) level, activities of some erythrocyte antioxidant enzymes, and plasma vitamin E and A levels. The groups were: nicotine (0.5 mg/kg/d, intraperitoneal, i.p.); nicotine؉vitamin E (75 mg/kg/d, intragastric, i.g.); nicotine؉HRe-1 (1 ml/kg/d, i.g.); and control group (receiving only vehicles). There were 8 rats per group and the supplementation period was 3 weeks. Nicotine-induced increase in erythrocyte MDA level was prevented by both HRe-1 and vitamin E. Nicotine-induced decrease in erythrocyte superoxide dismutase (SOD) activity was prevented by HRe-1, but not vitamin E. HRe-1 increased the erythrocyte glutathione peroxidase (GSH-Px) activity compared with nicotine and the vitamin E groups. Catalase activity was not affected. Vitamin E supplementation increased plasma vitamin E level. Plasma vitamin A level was higher in both vitamin E and HRe-1 supplemented groups compared with nicotine and control groups. The results suggest that HRe-1 extract can be used as a dietary supplement, especially by people who smoke, in order to prevent nicotine-induced oxidative stress.

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(-1)day(-1), intraperitoneal (i.p.)]; nicotine plus vitamin E [75 mg kg(-1)day(-1), intragastric (i.g.)]; nicotine plus HRe-1 (250 mg kg(-1)day(-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 alpha-tocopherol and beta-tocopherol and carotenoids such as alpha-carotene and beta-carotene, reported to be present in H. rhamnoides L. extracts may be responsible for the antioxidant effects of this plant extract.

No abstract

The aim of this work was to study the differences between the right- and left-visual cortices in relation to eyedness in healthy subjects. Ocular dominance was determined by means of the near-far alignment test. To assess visual cortical areas, the right and left sagittal scenograms of cranium by magnetic resonance imaging were used. To calculate the visual cortex areas by using scenograms, Cavalieri's method was used. In the subjects with right-eye dominance, the right visual cortex was larger than the left visual cortex, and vice versa in the subjects with left-eye dominance. The right and left cuneal areas were found to be larger in males than in females. In light of these results, it was concluded that the human eyes are predominantly controlled by the ipsilateral visual cortex.