No abstract

The polymorphisms of endothelial nitric oxide synthase (eNOS) are associated with reduced eNOS activity. Aerobic exercise training (AEX) may influence resting nitric oxide (NO) production, oxidative stress and blood pressure. The purpose of this study was to investigate the effect of AEX on the relationship among blood pressure, eNOS gene polymorphism and oxidative stress in pre-hypertensive older people. 118 pre-hypertensive subjects (59 ± 6 years) had blood samples collected after a 12 h overnight fast for assessing plasma NO metabolites (NOx) assays, thiobarbituric acid reactive substances (T-BARS) and superoxide dismutase activity (ecSOD). eNOS polymorphism (T-786C and G-894T) was done by standard PCR methods. All people were divided according to the genotype results (G1: TT/GG, G2: TT/GT + TT, G3: TC + CC/GG, G4: TC + CC/GT + TT). All parameters were measured before and after 6 months of AEX (70% of VO(2 max)). At baseline, no difference was found in systolic and diastolic blood pressure, ecSOD and T-BARS activity. Plasma NOx levels were significantly different between G1 (19 ± 1 μM) and G4 (14.2 ± 0.6 μM) and between G2 (20.1 ± 1.7 μM) and G4 (14.2 ± 0.6 μM). Therefore, reduced NOx concentration in G4 group occurred only when the polymorphisms were associated, suggesting that these results are more related to genetic factors than NO-scavenging effect. After AEX, the G4 increased NOx values (17.2 ± 1.2 μM) and decreased blood pressure. G1, G3 and G4 decreased T-BARS levels. These results suggest the AEX can modulate the NOx concentration, eNOS activity and the relationship among eNOS gene polymorphism, oxidative stress and blood pressure especially in C (T-786C) and T (G-894T) allele carriers.

Arterial hypertension (AH) has a high incidence in the world's population and its etiology is multifactorial, involving genetic, environmental and psychological factors 1,2. Its prevalence has progressively increased, especially among women, African descendants and the elderly. More than 50% of the subjects between 60 and 69 years of age and approximately ¾ of the population older than 70 years are affected by AH 1. Additionally, there is a positive and direct correlation between the elevated arterial pressure levels and the risk of cardiovascular diseases, regardless of gender, age range and ethnicity 1,2. Hence, the understanding of the cell and molecular mechanisms involved in the genesis of AH is fundamental for the attainment of preventive and/or therapeutic measures, with the objective of controlling pressure levels and consequently, reduce the cardiovascular risks associated with AH. Therefore, this review aims at discussing the mechanisms involved in the arterial pressure control, focusing on the role of the vascular endothelium and the importance of physical exercise in the regulation of nitric oxide production by endothelial cells.

Resumo -O envelhecimento é um processo inevitável, associado com o declínio fisiológico e da capacidade funcional do ser humano. O objetivo deste estudo foi verificar os efeitos de 12 anos de prática de atividade física em programa supervisionado, sobre a aptidão funcional em idosos. Dez idosas (idade média de 65 anos) participaram do estudo. Elas foram divididas em dois grupos: a) grupo treinado (GT), composto de 5 participantes que estavam atendendo um programa supervisionado que incluía diferentes tipos de atividades físicas de intensidade moderada; b) grupo não treinado (GNT), participantes que não estavam engajadas em programa supervisionado de atividade física, ambos nos últimos 12 anos. A aptidão funcional foi avaliada por meio da bateria de testes para idosos da AAHPERD que é composta por cinco testes: coordenação, flexibilidade, resistência de força, agilidade e equilíbrio dinâmico e resistência aeróbia geral. Os resultados mostram que as idosas que permaneceram no programa de atividade física apresentaram melhor desempenho nos testes motores. Portanto, enquanto idosas que continuam a participar regularmente de atividades físicas num programa supervisionado tendem a melhorar ou manter todos os componentes de aptidão funcional, mesmo durante o longo período de 12 anos, aquelas que só realizam atividades físicas requeridas nas tarefas da vida diária, tendem a reduzir a maioria daqueles componentes. As evidências do presente estudo possibilitam predizer diferenças de aptidão funcional, cada vez maiores, entre os dois grupos, com o passar do tempo, o que pode produzir efeitos de direção oposta nas respectivas qualidades de vida. Palavras-chave: Envelhecimento; Aptidão funcional; Atividade física; Qualidade de vida. Abstract -Aging is an inevitable process and is associated with declining physiological and functional capacity in humans. The objective of this study was to determine the effects of a 12-year