Pleurotus albidus (Agaricomycetes) Antioxidant Action Induces Vasodilation in Aorta Arteries: The Influence of the NADPH/NOS Balance.

The main objective of this work was to evaluate whether Pleurotus albidus extract exerts influences on aorta artery tone by its antioxidant properties. The hearts and aortic arteries of male Wistar rats were removed for use in biochemical analysis and vascular reactivity. Both tissues were exposed to P. albidus extract at different concentrations for 30 min and were then exposed to a free radical generation system for 30 min. The extract reduced lipid peroxidation levels and increased catalase and glutathione peroxidase activity in cardiac tissue. In the aorta, P. albidus extract demonstrated a direct vasodilatory effect, which was associated with a reduction in nicotinamide adenine dinucleotide phosphate oxidase (NOX) activity and an increase in sulfhydryl levels and nitric oxide synthase (NOS) activity. Our findings suggest that P. albidus extract has regulatory potential on aorta arteries, regulating the balance of NOX/NOS enzymes and then influencing vessel tone. Further studies are needed to determine the protective mechanisms of the extract.

Effect of Free and Nanoencapsulated Copaiba Oil on Monocrotaline-induced Pulmonary Arterial Hypertension.

Copaiba oil comes from an Amazonian tree and has been used as an alternative medicine in Brazil. However, it has not been investigated yet in the treatment of cardiovascular diseases. This study was designed to test whether copaiba oil or nanocapsules containing this oil could modulate monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH). Male Wistar rats (170 ± 20 g) received oil or nanocapsules containing this oil (400 mg/kg) by gavage daily for 1 week. At the end of this period, a single injection of MCT (60 mg/kg i.p.) was administered and measurements were performed after 3 weeks. The animals were divided into 6 groups: control, copaiba oil, nanocapsules with copaiba oil, MCT, oil + MCT, and nanocapsules + MCT. Afterward, echocardiographic assessments were performed, and rats were killed to collect hearts for morphometry and oxidative stress. MCT promoted a significant increase in pulmonary vascular resistance, right ventricle (RV) hypertrophy, and RV oxidative stress. Both oil and copaiba nanocapsules significantly reduced RV hypertrophy and oxidative stress. Pulmonary vascular resistance was reduced by copaiba oil in natura but not by nanocapsules. In conclusion, copaiba oil seems to offer protection against MCT-induced PAH. Our preliminary results suggest that copaiba oil may be an important adjuvant treatment for PAH.

Effects of isolated vitamin B6 supplementation on oxidative stress and heart function parameters in experimental hyperhomocysteinemia

Introduction: The purpose of this study was to investigate the effects of isolated vitamin B6 (VB6 ) supplementation on experimental hyperhomocysteinemia (Hhe) induced by homocysteine thiolactone (HcyT). Methods: Fifteen male Wistar rats were divided into three groups according to their treatment. Animals received water and food ad libitum and an intragastric probe was used to administer water for 60 days (groups: CB6, HcyT, and HB6 ). On the 30th day of treatment, two groups were supplemented with VB6 in the drinking water (groups: CB6 and HB6 ). After 60 days of treatment, homocysteine (Hcy), cysteine, and hydrogen peroxide concentration, nuclear factor (erythroid-derived 2)-like 2 (NRF2) and glutathione S-transferase (GST) immunocontent, and superoxide dismutase (SOD), catalase (CAT), and GST activities were measured. Results: The HcyT group showed an increase in Hcy concentration (62%) in relation to the CB6 group. Additionally, GST immunocontent was enhanced (51%) in the HB6 group compared to the HcyT group. Also, SOD activity was lower (17%) in the HB6 group compared to the CB6 group, and CAT activity was higher in the HcyT group (53%) compared to the CB6 group. Ejection fraction (EF) was improved in the HB6 group compared to the HcyT group. E/A ratio was enhanced in the HB6 group compared to the CB6 group. Correlations were found between CAT activity with myocardial performance index (MPI) (r = 0.71; P = 0.06) and E/A ratio (r = 0.6; P = 0.01), and between EF and GST activity (r = 0.62; P = 0.02). Conclusions: These findings indicate that isolated VB6 supplementation may lead to the reduction of Hcy concentration and promotes additional benefits to oxidative stress and heart function parameters (AU)