EFECTOS DE METFORMINA SOBRE LOS NIVELES DE NITROOXIDACIÓN EN PACIENTES HIPERTENSOS CON SÍNDROME METABÓLICO

Abstract

Introduction. Metabolic syndrome (MS) is a cluster of risk factors for developing type 2 diabetes and cardiovascular disease characterized by insulin resistance and compensatory hyperinsulinemia associated with disorder of metabolism of carbohydrates and lipids, hypertension and obesity. Objective. To observe the effect of metformin on serum biomarkers of oxidative stress in hypertensive patients with MS who are treated with metformin and those not treated with metformin. Methods. Were randomized 50 patients of both sexes between 35 and 60 years diagnosed with hypertension and MS by IDF criteria in two groups: control (n=25) and metformin 850mg per day (n=25). Weight, abdominal circumference, BMI, fasting glucose, total cholesterol, HDL-c, malonaldehyde, carbonyls, nitrates, s-nitrosylation and endothelial function were assessed. Vasodilatation mediated flux (VMF) and measurement of carotid intima-media thickness (CIMT) were also assessed. Both groups received nutritional and exercise counseling and were evaluated every 6 months during one year. An analysis of variance was done with a significant p<0.05. Results. Both groups reduced weight, BMI, total cholesterol, abdominal circumference, triglycerides, blood pressure, CIMT. Only the metformin group showed significant decrease in glucose levels (1.9 md/dl), carbonyls (0.44 nmol/mg protein) and increased HDL-c (4.9 mg/dl). An improvement in endothelial function was observed in metformin group without statistics significance. The control group showed an elevation in the biomarker s-nitrosylation. Conclusions. Metformin improved levels of carbonyls precursors of AGES responsible for the endothelial activation, inflammation and vascular damage. Long term studies are needed to determine whether metformin is a useful drug to ameliorate the cardiovascular risk in patients with MS.