-Besides neuronal plasticity, the neurotrophin brain-derived neurotrophic factor (BDNF) is also important in vascular function. The BDNF has been associated with angiogenesis through its specific receptor tropomyosin-related kinase B (TrkB). Additionally, Val66Met polymorphism decreases activity-induced BDNF. Since BDNF and TrkB are expressed in vascular endothelial cells and aerobic exercise training can increase serum BDNF, this study aimed to test the hypotheses: 1) Serum BDNF levels modulate peripheral blood flow; 2) The Val66Met BDNF polymorphism impairs exercise training-induced vasodilation. We genotyped 304 healthy male volunteers (Val66Val, n ϭ 221; Val66Met, n ϭ 83) who underwent intense aerobic exercise training on a running track three times/wk for 4 mo. We evaluated pre-and post-exercise training serum BDNF and proBDNF concentration, heart rate (HR), mean blood pressure (MBP), forearm blood flow (FBF), and forearm vascular resistance (FVR). In the pre-exercise training, BDNF, proBDNF, BDNF/proBDNF ratio, FBF, and FVR were similar between genotypes. After exercise training, functional capacity (V O2 peak) increased and HR decreased similarly in both groups. Val66Val, but not Val66Met, increased BDNF (interaction, P ϭ 0.04) and BDNF/proBDNF ratio (interaction, P Ͻ 0.001). Interestingly, FBF (interaction, P ϭ 0.04) and the FVR (interaction, P ϭ 0.01) responses during handgrip exercise (HG) improved in Val66Val compared with Val66Met, even with similar responses of HR and MBP. There were association between BDNF/proBDNF ratio and FBF (r ϭ 0.64, P Ͻ 0.001) and FVR (r ϭ Ϫ0.58, P Ͻ 0.001) during HG exercise. These results show that peripheral vascular reactivity and serum BDNF responses to exercise training are impaired by the BDNF Val66Met polymorphism and such responsiveness is associated with serum BDNF concentrations in healthy subjects.BDNF Val66Met polymorphism; exercise training; vascular reactivity EXERCISE TRAINING HAS BEEN considered a key element in the improvement in brain-derived neurotrophic factor (BDNF) levels (39), which is the strongest factor linking exercise with cognitive benefits. However, the variability of individual responses may be linked to genetic differences.While BDNF promotes neuronal survival and enhanced synaptic plasticity by activating the tropomyosin kinase B (TrkB) receptor, the action of its precursor proBDNF results in apoptosis by interacting with the p75 neurotrophin receptor (p75NTR), and both are significantly involved in different physiological functions (15,53).Considering the fact that the BDNF gene and its TrkB receptor are expressed in several tissues, such as brain, heart, lungs, and endothelial cells (12, 28), besides neuronal plasticity, it is possible that the neurotrophin BDNF also is involved in the health of other tissues. Indeed, besides the hippocampus, the circulating BDNF is produced by a number of peripheral nonneuronal tissues, including vascular endothelial cells (28,53). Moreover, the neurotrophin BDNF has been associated with angiogenesis thro...

Peripheral blood cells are an accessible environment in which to visualize exercise-induced alterations in global gene expression patterns. We aimed to identify a peripheral blood mononuclear cell (PBMC) signature represented by alterations in gene expression, in response to a standardized endurance exercise training protocol. In addition, we searched for molecular classifiers of the variability in oxygen uptake (V̇o2). Healthy untrained policemen recruits (n = 13, 25 ± 3 yr) were selected. Peak V̇o2 (measured by cardiopulmonary exercise testing) and total RNA from PBMCs were obtained before and after 18 wk of running endurance training (3 times/wk, 60 min). Total RNA was used for whole genome expression analysis using Affymetrix GeneChip Human Gene 1.0 ST. Data were normalized by the robust multiarray average algorithm. Principal component analysis was used to perform correlations between baseline gene expression and V̇o2peak. A set of 211 transcripts was differentially expressed (ANOVA, P < 0.05 and fold change > 1.3). Functional enrichment analysis revealed that transcripts were mainly related to immune function, cell cycle processes, development, and growth. Baseline expression of 98 and 53 transcripts was associated with the absolute and relative V̇o2peak response, respectively, with a strong correlation (r > 0.75, P < 0.01), and this panel was able to classify the 13 individuals according to their potential to improve oxygen uptake. A subset of 10 transcripts represented these signatures to a similar extent. PBMCs reveal a transcriptional signature responsive to endurance training. Additionally, a baseline transcriptional signature was associated with changes in V̇o2peak. Results might illustrate the possibility of obtaining molecular classifiers of endurance capacity changes through a minimally invasive blood sampling procedure.

RESUMOIntrodução: A determinação do limiar anaeróbio em exercícios resistidos tem sido tema de diversos estudos. No entanto, o impacto desta avaliação sobre os parâmetros hemodinâmicos de pressão arterial e frequência cardíaca ainda é desconhecido. Objetivo: Comparar a estimativa do limiar anaeróbio (LAn) obtido em teste e reteste de protocolo incremental nos exercícios resistidos de supino reto (SR) e rosca direta (RD) e analisar o comportamento das variáveis hemodinâmicas de frequência cardíaca (FC), pressão arterial sistólica (PAS) e diastólica (PAD) durante protocolo de cargas incrementais.