Vitamins C and E improve endothelial dysfunction in intrauterine-undernourished rats by decreasing vascular superoxide anion concentration.

Abstract

Epidemiological studies suggest that intrauterine undernutrition plays an important role in the development of arterial hypertension in adulthood. Ascorbic acid (vitamin C) and alpha-tocopherol (vitamin E) have antioxidant properties that could improve redox-sensitive vascular changes associated with hypertension. The authors determined whether vitamins C and E treatments ameliorate the hypertension and vascular function in male rats submitted to intrauterine undernutrition. Pregnant Wistar rats were fed either normal or 50% of the normal intake diets during the whole gestational period. At 14 weeks of age, male offspring of nutritionally restricted dams were divided into 3 subgroups: vehicle-treated (vehicle for 15 days, by gastric gavage, n = 9), vitamin C-treated (ascorbic acid, 150 mg/Kg/d for 15 days, by gastric gavage, n = 15) and vitamin E-treated (alpha-tocopherol, 350 mg/kg per day for 15 days, by gastric gavage, n = 15). Systolic blood pressure was determined before and after antioxidant treatments by the tail-cuff method. At 16 weeks of age, the rats were used for the study of microvascular reactivity and intravital fluorescence microscopy. Intrauterine undernutrition induced hypertension, and vitamins C or E treatments reduced the blood pressure levels. The decreased acetylcholine and bradykinin-induced vasodilation was restored in the vitamin-treated rats. These effects were associated with decreased vascular superoxide anion concentration. The results show that vitamins C and E reduce oxidative stress and high blood pressure levels, and improve vascular function in intrauterine-undernourished rats.