ABSTRACT
BACKGROUND/AIMS: Hypertensive patients present with increased oxidative stress and frequently receive angiotensin II (ANGII) receptor type I blockers (ARB) for blood pressure (BP) reduction. Recent studies revealed an important role of ANGII in maintaining vascular oxidative homeostasis, including sustaining normal sodium dismutase activity. This study aimed to investigate the effects of antihypertensive therapy and also vitamin C/E supplementation on BP, oxidative stress and endothelial activation in patients with essential hypertension. METHODS: Newly discovered patients received ARB/olmesartan or the Ca2+-channel blocker (CCB)/amlodipine, and additionally vitamin C/E or placebo throughout weeks 9-16. ELISA was used to determine 8-iso-prostaglendin F2-alpha (8iPGF2α) and endothelial activation markers. RESULTS: In both groups BP was normalized during first 8 weeks of therapy. Vitamins C/E had no additional BP-lowering effect. The vitamins C/E supplementation was not effective in reducing absolute values of 8iPGF2α; however; the magnitude of 8iPGF2α reduction was significantly greater in patients taking vitamins C/E in the CCB group. Although plasma 8iPGF2α positively correlated to BP, a significant decrease occurred during an additional 8 weeks of treatment. There were no changes in endothelial activation markers related to the specific action of ARB or CCB. CONCLUSIONS: Present study suggests that observed oxidative stress is a consequence of hypertension. BP reduction is associated with the observed decrease in oxidative stress and changes in endothelial activation regardless of antihypertensive therapy.
Subject(s)
Antihypertensive Agents/pharmacology , Endothelium, Vascular/metabolism , Hypertension/metabolism , Oxidative Stress/drug effects , Adult , Amlodipine/pharmacology , Angiotensin II Type 1 Receptor Blockers/therapeutic use , Blood Pressure/drug effects , Calcium Channel Blockers/therapeutic use , Endothelium, Vascular/drug effects , Female , Humans , Hypertension/drug therapy , Imidazoles/pharmacology , Male , Middle Aged , Tetrazoles/pharmacology , Vitamins/pharmacologyABSTRACT
Placental selenium, lead and cadmium concentrations were determined in a group of pregnancies with birth weight appropriate for gestational age and in a group of intrauterine growth restriction cases. Following adjustment for a number of confounding variables, selenium was found to be a significant predictor of newborn weight only in the group of pregnancies with birth weights appropriate for gestational age. Placental lead and cadmium levels were not associated with birth weight in either group.