Brazil nut supplementation does not affect trimethylamine-n-oxide plasma levels in patients with coronary artery disease.

The purposes of this study were to assess the effect of Brazil nut supplementation on trimethylamine N-oxide (TMAO) levels and glutathione peroxidase (GPx) activity in patients with coronary artery disease (CAD). Patients with CAD were randomly assigned to two groups, Brazil nut group (23 patients, 48% male, 62.7 ± 6.8 years, 29.4 ± 5.8 kg/m2 ), which received one Brazil nut per day for 3 months, and the control group (14 patients, 43% male, 63.7 ± 8.7 years, 28.4 ± 4.2 kg/m2 ) who did not receive any supplementation. After 3 months, TMAO levels and their precursors did not change in either group. Although not significant, GPx activity increased by 41% in the Brazil nut group. TMAO levels were negatively associated with total fiber intake (r = -0.385 and p = .02). A 3-month Brazil nut supplementation did not change TMAO levels and GPx activity in CAD patients. PRACTICAL APPLICATIONS: Trimethylamine N-oxide (TMAO) has been associated with oxidative stress and cardiovascular disease risk. Thus, the increase in antioxidants enzymes production could be a promising strategy to reduce TMAO-mediated oxidative stress. In this context, nutritional strategies are well-known as activators of cellular antioxidant responses. As Brazil nuts have a known role in reducing oxidative stress by increasing glutathione peroxidase (GPx) activity (a selenium-dependent antioxidant enzyme), this study hypothesized that Brazil nuts could be a strategy that, via antioxidant capacity, would reduce TMAO plasma levels. Although no changes in TMAO levels and GPx activity can be observed in this study, it is believed that other results can be obtained depending on the dosage used. Thus, this study can open new paths and direct other studies with different doses and treatment times to evaluate the effects of Brazil Nuts on TMAO levels.

Brazil Nut Supplementation Does Not Regulate PPARß/δ Signaling Pathway in Peripheral Blood Mononuclear Cells from Coronary Artery Disease Patients.

Background: Peroxisome proliferator-activated receptor (PPAR)ß/δ activation is a potential target for modulation of inflammation in cardiovascular disease. PPARß/δ activation depends on the presence of a ligand, which may be pharmacological or natural, such as bioactive compounds and nutrients. Due to its composition, rich in selenium and unsaturated fatty acids, Brazil nuts have been related to reduced oxidative stress and inflammation in chronic non-communicable diseases and could regulate PPARß/δ. This study aimed to evaluate the effects of Brazil nut supplementation on PPARß/δ mRNA expression in patients with Coronary Artery Disease (CAD).Methods: A secondary analysis of a randomized controlled clinical trial was performed with 36 CAD patients. Patients were randomly assigned to either the Supplementation group or the control group and followed up for three months. The Supplementation group consumed 1 Brazil nut/day; the control group did not receive any intervention. At the baseline and after three months, analysis of gene expression and biochemical parameters linked to inflammatory biomarkers and oxidative stress was carried out.Results: In the supplementation group, no significant change was observed in PPARß/δ (0.9 ± 0.5 vs 1.2 ± 0.6; p = 0.178) and NF-κB (1.6 ± 1.5 vs 0.8 ± 0.30, p = 0.554) mRNA expression. There were no significant changes in both groups concerning all the other biochemical parameters.Conclusion: One Brazil nut per day for three months was not able to increase the PPARß/δ expression in CAD patients.