Improvement of antioxidant status after Brazil nut intake in hypertensive and dyslipidemic subjects

Objectives: To investigate the effect of partially defatted Granulated Brazil nut (GBN) on biomarkers of oxidative stress and antioxidant status of hypertensive and dyslipidemic patients on nutrition and drug approaches. Methods: Ninety one hypertensive and dyslipidemic subjects of both genders (51.6 % men), mean age 62.1 +/- 9.3 years, performed a randomized crossover trial, double-blind, placebo controlled. Subjects received a diet and partially defatted GBN 13 g per day (approximate to 227.5 mu g/day of selenium) or placebo for twelve weeks with four-week washout interval. Anthropometric, laboratory and clinic characteristics were investigated at baseline. Plasma selenium (Se), plasma glutathione peroxidase (GPx3) activity, total antioxidant capacity (TAC), 8-epi PGF(2 alpha) and oxidized LDL were evaluated at the beginning and in the end of each intervention. Results: GBN intake significantly increased plasma Se from 87.0 +/- 16.8 to 180.6 +/- 67.1 mu g/L, increased GPx3 activity in 24,8 % (from 112.66 +/- 40.09 to 128.32 +/- 38.31 nmol/min/mL, p < 0,05), and reduced 3.25 % of oxidized-LDL levels (from 66.31 +/- 23.59 to 60.68 +/- 20.88 U/L, p < 0.05). An inverse association between GPx3 and oxidized LDL levels was observed after supplementation with GBN by simple model (beta -0.232, p = 0.032) and after adjustment for gender, age, diabetes and BMI (beta -0.298, p = 0.008). There wasn't association between GPx3 and 8-epi PGF(2 alpha) (beta -0.209, p = 0.052) by simple model. Conclusion: The partially defatted GBN intake has a potential benefit to increase plasma selenium, increase enzymatic antioxidant activity of GPx3 and to reduction oxidation in LDL in hypertensive and dyslipidemic patients.