The Molecular Effects of BDNF Synthesis on Skeletal Muscle: A Mini-Review.

The brain-derived neurotrophic factor (BDNF) is a member of the nerve growth factor family which is generated mainly by the brain. Its main role involve synaptic modulation, neurogenesis, neuron survival, immune regulation, myocardial contraction, and angiogenesis in the brain. Together with the encephalon, some peripheral tissues synthesize BDNF like skeletal muscle. On this tissue, this neurotrophin participates on cellular mechanisms related to muscle function maintenance and plasticity as reported on recent scientific works. Moreover, during exercise stimuli the BDNF contributes directly to strengthening neuromuscular junctions, muscle regeneration, insulin-regulated glucose uptake and ß-oxidation processes in muscle tissue. Given its vital relevance on many physiological mechanisms, the current mini-review focuses on discussing up-to-date knowledge about BDNF production in skeletal muscle and how this neurotrophin impacts skeletal muscle biology.

Exercise intensity and physical fitness modulate lipoproteins profile during acute aerobic exercise session.

Physical inactivity has emerged as an important cardiometabolic risk factor; however, the beneficial impacts of physical exercise according physical fitness status are still unclear. To analyze the lipoproteins and immune-endocrine response to acute aerobic exercise sessions performed at different intensities according physical fitness status and evaluated the gene expression in monocyte cells. Twelve individuals, divided into Low and High VO2max, performed three randomized acute exercise sessions at low (<60% VO2max), moderate (60-75% VO2max), and high (>90% VO2max) intensities. Blood samples were collected pre, immediately post, and 60 minutes post-exercise to analyze NEFA, triacylglycerol, non-HDL-c, HDL-c, PAI-1, leptin and adiponectin concentrations. Blood samples were collected from another set of twelve individuals for use in monocyte cell cultures to analyze L-CAT, CETP, and AMPK gene expressions. Low VO2max group pre-exercise exhibited higher postprandial leptin and total cholesterol concentrations than High VO2max group (p < 0.05). Exercise performed in high-intensity promoted a decreased leptin and NEFA levels (p < 0.05, for both), but for PAI-1 levels was decreased (p < 0.05) only for the Low VO2max group. Triacylglycerol levels decreased after all exercise sessions (p < 0.05) for both groups, and HDL-c exhibited decrease during moderate-intensity (p < 0.05), but this scenario was attenuated in Low VO2max group. Low VO2max individuals exhibit some metabolic-endocrine disruption, and acute aerobic exercise sessions performed at low, moderate, and high intensities are capable of modulating metabolic-endocrine parameters, mainly at high-intensity, in a physical fitness-dependent way, given that Low VO2max group was more responsive and seem to be able to appropriate more exercise-related benefits.

Impact of 5-week high-intensity interval training on indices of cardio metabolic health in men.

PURPOSE: To compare the acute and chronic effects of high-intensity intermittent training (HIIT) and moderate-intensity continuous training (MICT) on indices of cardio-metabolic health: (HDL-c, total cholesterol, triglycerides, heart ratio, and phase angle/PhA) in physically active men. METHODS: Twenty active men were randomly allocated to HIIT (n = 10), or MICT (n = 10) for 5 weeks, three times per week. HIIT consisted of running 5 km with 1-min at 100% of maximal aerobic speed interspersed by 1-min passive recovery while subjects in MICT group ran continuously the same 5 km at 70% of maximal aerobic speed. Blood samples were collected at different moments during the first and last exercise session. Before and after 5 weeks of both exercise training protocols, heart ratio (during exercise session) and PhA were measured pre and post-exercise training. RESULTS: Fasting HDL-c levels did not change after 5 weeks of HIIT or MICT. Perceptual variation of HDL pre and post training (fed state) tended to differ between HIIT and MICT (p = 0.09). All lipoproteins parameters (HDL-c, total cholesterol, triglycerides and non-HDL) were increased in post-acute exercise session compared to pre-exercise during the first and last training session, these being observed after both training protocols. PhA and heart rate measured at different times during the first and last training session were not affected in both training protocols. CONCLUSION: These results indicate that HIIT and MICT modify the post-exercise lipoprotein profile acutely. On the other hand, only HIIT tended to increase HDL-c levels chronically.

Sleep quality and duration are associated with performance in maximal incremental test.

BACKGROUND AND OBJECTIVE: Inadequate sleep patterns may be considered a trigger to development of several metabolic diseases. Additionally, sleep deprivation and poor sleep quality can negatively impact performance in exercise training. However, the impact of sleep duration and sleep quality on performance during incremental maximal test performed by healthy men is unclear. Therefore, the purpose of the study was to analyze the association between sleep pattern (duration and quality) and performance during maximal incremental test in healthy male individuals. METHODS: A total of 28 healthy males volunteered to take part in the study. Sleep quality, sleep duration and physical activity were subjectively assessed by questionnaires. Sleep pattern was classified by sleep duration (>7h or <7h of sleep per night) and sleep quality according to the sum of measured points and/or scores by the Pittsburgh Sleep Quality Index (PSQI). Incremental exercise test was performed at 35 watts for untrained subjects, 70 watts for physically active subjects and 105 watts for well-trained subjects. RESULTS: HRmax was correlated with sleep quality (r=0.411, p=0.030) and sleep duration (r=-0.430, p=0.022). Participants reporting good sleep quality presented higher values of Wmax, VO2max and lower values of HRmax when compared to participants with altered sleep. Regarding sleep duration, only Wmax was influenced by the amount of sleeping hours per night and this association remained significant even after adjustment by VO2max. CONCLUSION: Sleep duration and quality are associated, at least in part, with performance during maximal incremental test among healthy men, with losses in Wmax and HRmax. In addition, our results suggest that the relationship between sleep patterns and performance, mainly in Wmax, is independent of fitness condition.

Arterial Thickness and Immunometabolism: The Mediating role of Chronic Exercise.

Metabolic alterations and cardiovascular diseases, such as atherosclerosis, are associated with lifestyle modifications, particularly the increase of physical inactivity and poor eating habits, which contribute to one of the main causes of death in modern times. Cardiovascular diseases are positively correlated with several illnesses, such as obesity, hypertension and dyslipidemia, and these disorders are known to contribute to changes in immune cells, cytokines and metabolism. Atherosclerosis is a chronic inflammatory disease characterized by the formation of lipid plaques and fibrous tissue (atheroma) in the artery walls and this process is related to the oxidation of LDL-c (low density lipoprotein) and the formation of a particle, termed LDLox, which can generate toxic injury to the vessel wall. In this atherogenic process there is an inflammatory response generated by the injury in the vascular endothelium, which in itself is able to express and secrete a variety of molecules, such as myeloid colony-stimulating factors (M-CSF), monocyte chemotactic protein-1 (MCP-1) and tumor necrosis factor alpha (TNF-α), that act as activators of the immune system. Therefore, the main purpose of this review is to highlight the immuno-metabolic alterations involving the thickening and stiffness of arteries observed in atherosclerosis, and how chronic exercise can act as an anti-inflammatory and anti-atherogenic approach.

The relationship between inflammation, dyslipidemia and physical exercise: from the epidemiological to molecular approach.

Dyslipidemia and inflammation are frequently found in some diseases, such as obesity, type 2 diabetes mellitus, and cancer cachexia. Recent literature has identified that lipids have a pivotal role in the activation of inflammatory pathways, increasing the production of inflammatory cytokines, mainly tumor necrosis factor alpha, interleukin 6 and 1ß. On the other hand, cytokines can promote disruption of lipid metabolism, in special cholesterol reverse transport, which is linked to development of atherosclerosis. With this in mind, acute and chronic exercise trainings have been pointed as important tools to counteract both dyslipidemia symptoms and systemic inflammation. Moreover, physical activity has been recommended in the prevention/treatment of the above mentioned outcomes by important health organizations around the world, mainly because it costs less and generates fewer side effects than isolated medicine. Despite the well-documented capacity of acute and chronic exercise training to counteract sustained disease-related immunometabolism, we have chosen to take a look from a current perspective in molecular pathways and in the field of epidemiology. The aim of the present review was therefore to discuss the results of dyslipidemia and inflammatory conditions with acute and chronic exercise training, which underlies the field of molecular pathways and epidemiology. The mechanisms underlying the response to the treatment are considered.