Cleber A. Pinho

Effects of different physical training protocols on ventricular oxidative stress parameters in infarction-induced rats

AIM Physical exercise is important in the prevention and treatment of cardiovascular diseases. Nevertheless, controversy remains around type and intensity of effort required for significant biochemical protective changes. This study investigates two exercise protocols on ventricular oxidative parameters in rats post-infarction. MAIN METHODS Thirty-six 2-month-old male Wistar rats were divided in two groups (n=18): Sham and acute myocardial infarction (AMI) conducted by blocking the coronary artery. Thirty days after AMI, animals were divided in 6 subgroups (n=6): sham, sham+continuous training (60 min), sham+interval training, AMI, AMI+continuous training, and AMI+interval training. Training was conducted in water (30-32°C) 5 times a week for 6 weeks. Animals were sacrificed 48 h after the last exercise routine. Left ventricles were used for oxidative stress analyses (antioxidant enzyme activity and level, oxidative damage) and HIF1α and cit c oxidase expression. KEY FINDINGS After AMI, both exercise models decreased superoxide levels significantly. Training routines did not alter SOD expression and activity, though CAT expression increased with continuous training and GPX level diminished in both training groups, which coincided with the increase in GPX activity. Lipid damage decreased only in the continuous training group, while protein damage decreased only in the interval training group. Cytochrome C increased in both groups, while HIF-1 α dropped significantly after both exercise protocols. SIGNIFICANCE Significant improvement occurred in myocardium redox status in rats challenged with AMI after different training routines. However, continuous training seems to be more efficient in improving the parameters analyzed.

Oxidative Stress and Inflammatory Parameters After an Ironman Race

Objective: The aim of the present study was to investigate oxidative stress markers and inflammatory response in triathletes after an Ironman race (IR). Design: Descriptive research. Participants: Eighteen well-trained male triathletes (mean age, 34.7 ± 2.15 years; weight, 69.3 ± 1.9 kg; height, 1.81 ± 0.58 cm) participated in the study. Setting: Ironman Triathlon (3.8-km swim, 180-km cycle, 42.2-km run). Mean environmental conditions ranged from 20 to 25°C and from 79% to 85% relative humidity. Interventions: None. Main Outcome Measures: Before the race and up to 20 minutes after completing the full race, the weights and heights of volunteers were measured and a 10 mL blood sample was drawn from an antecubital vein. Aliquots of washed/lysed red blood cells and plasma/serum samples were stored at −80°C. Lipid peroxidation, protein carbonylation, superoxide dismutase and catalase activities, and cytokines levels [tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, IL-10, and IL-1ra] were determined. Results: After the IR, the results showed a significant increase in TBARS levels (prerace = 1.15 ± 0.11; postrace = 1.98 ± 0.27), lipid hydroperoxide content (prerace = 0.75 ± 0.03; postrace = 1.46 ± 0.18), protein carbonylation (prerace = 0.67 ± 0.12; postrace = 2 0.15 ± 0.60), superoxide dismutase (prerace = 2.67 ± 0.62; postrace = 3.97 ± 1.48), and catalase (prerace = 1.48 ± 0.18; postrace = 2.84 ± 0.39). TNF-α, IL-6, and IL-10 were not detected at basal conditions, but all markers were significantly increased after the IR (TNF-α: prerace = ND and postrace = 67.47 ± 10.34; IL-6: prerace = ND and postrace = 55.41 ± 3.45; IL-10: prerace = ND and postrace = 122.53 ± 9.69; IL-1ra: prerace = 127.79 ± 25.65 and postrace = 259.51 ± 32.9). Conclusions: An Ironman race provokes significant alterations in oxidative stress and inflammatory parameters. Thus, more studies with other markers and different designs are needed to elucidate the cellular alterations induced by an IR.

Mitochondrial IV complex and brain neurothrophic derived factor responses of mice brain cortex after downhill training

Twenty-four adult male CF1 mice were assigned to three groups: non-runners control, level running exercise (0 degrees incline) and downhill running exercise (16 degrees decline). Exercise groups were given running treadmill training for 5 days/week over 8 weeks. Blood lactate analysis was performed in the first and last exercise session. Mice were sacrificed 48 h after the last exercise session and their solei (citrate synthase activity) and brain cortices (BDNF levels and cytochrome c oxidase activity) were surgically removed and immediately stored at -80 degrees C for later analyses. Training significantly increased (P<0.05) citrate synthase activity when compared to untrained control. Blood lactate levels classified the exercise intensity as moderate to high. The downhill exercise training significantly reduced (P<0.05) brain cortex cytochrome c oxidase activity when compared to untrained control and level running exercise groups. BDNF levels significantly decreased (P<0.05) in both exercise groups.

Interval training does not decrease oxidative stress in the heart of mice

Physical exercise is characterized by an increase in O2 consumption by the whole body— particularly by heart tissues— linked with a rise in the production of ROS [1], which in turn is associated with the mechanisms of cardiac dysfunction [2]. Studies on both involuntary treadmill exercise training [3] and voluntary wheel running [4] in animals have consistently demonstrated that endurance with moderate intensity exercise is associated with increased aerobic capacity and improved oxidative stress parameters. Nevertheless, to date, no studies have compared the effect of interval training with continuous training on oxidative stress parameters in cardiac muscle. In our Laboratory, we have compared the effect of different types of training, interval (3×15 min/day−1, totaling 45 min) and continuous (1×45 min/day), on oxidative capacity (mitochondrial respiratory chain enzyme activities) and oxidative stress parameters (oxidative damage and antioxidant enzymes). Using male mice (CF1), weighing 30–35 g, randomly distributed into three groups (untrained, UT; interval running, IR; continuous running, CR; n=7) and submitted to an 8-week training program (50–60%Vo2max/5 day/wk), we observed that interval training caused no reduction in oxidative stress parameters, and that it is less efficient in terms of heart muscle oxidative capacity than continuous exercise (Table 1). Adaptation of muscle depends on the frequency, intensity and duration of exercise [5]. It is possible that training at a moderate intensity for a prolonged period (45 min) effectively enhances the overall capacity to transport and use oxygen, inducing increased mitochondrial respiratory chain enzyme activities. Most studies investigating the influence of physical training on tissue antioxidant status [1,4] have shown that continuous intensity exercise (2 h per day/8wk/5 days/wk) induces significant increases inMDA in the heart [6], whilst moderate exercise training (55–65% Vo2max/5 day/wk) decreases lipoperoxidation in the mouse heart [7]. We observed that continuous training reduces oxidative damage to lipids and protein and increased total thiol content in theheart; in contrast, interval trainingwas not sufficient to reduce these markers. Data demonstrate that daily

Avaliação sérica de danos musculares e oxidativos em atletas após partida de futsal

O futsal e uma modalidade esportiva que requer subita aceleracao e desace-leracao com brusca mudanca de direcao. Este esporte expoe seus praticantes a grandes impactos, causando danos musculares e oxidativos. O objetivo desta pesquisa foi avaliar os niveis sericos de marcadores de danos musculares e oxidativos em atletas apos jogo de futsal. Participaram do estudo, seis atletas de futsal, com idade media (21,2 ± 0,98 anos), peso (67,1 ± 5,5 kg) e altura (171,0 ± 0,07 cm). As coletas foram obtidas 30 minutos antes do jogo 1 (Pre-jogo); imediatamente apos o jogo 1 (pos-jogo 1) e imediatamente apos o segundo jogo (pos-jogo 2), que foi realizado 24 horas apos o jogo 1. O soro foi utilizado para avaliacoes sericas de creatina quinase, dano proteico e lipidico. As concentracoes de creatina quinase, peroxidacao lipidica (xilenol) e carbonilacao de proteina (carbonil) foram significativamente maiores apos o termino dos jogos 1 e 2, quando comparadas aos valores pre jogo. Os valores de sulfidrila foram menores apos o termino dos jogos 1 e 2, quando comparados aos valores pre jogo. Nenhuma diferenca foi observada quando comparados os valores apos jogo 1 e o jogo 2 em todos os parâmetros analisados. Coletivamente, os resultados demonstram que a partida de futsal provoca danos musculares e oxidativos. Surpreendentemente, nao houve incremento nos parâmetros avaliados ao final do jogo 2. Devido ao reduzido conhecimento em relacao ao tempo de recuperacao apos uma partida de futsal, acredita-se que este estudo seja de grande importância para os profissionais que trabalham com esse esporte. .O futsal e uma modalidade esportiva que requer subita aceleracao e desaceleracao com brusca mudanca de direcao. Este esporte expoe seus praticantes a grandes impactos, causando danos musculares e oxidativos. O objetivo desta pesquisa foi avaliar os niveis sericos de marcadores de danos musculares e oxidativos em atletas apos jogo de futsal. Participaram do estudo, seis atletas de futsal, com idade media (21,2 ± 0,98 anos), peso (67,1 ± 5,51 Kg) e altura (171,0 ± 17 cm). As coletas foram obtidas 30 minutos antes do jogo 1 (Pre-jogo); imediatamente apos o jogo 1 (pos-jogo 1) e imediatamente apos o segundo jogo (pos-jogo 2), que foi realizado 24 horas apos o jogo 1. O soro foi utilizado para avaliacoes sericas de creatina quinase, dano proteico e lipidico. As concentracoes de creatina quinase, peroxidacao lipidica (xilenol) e carbonilacao de proteina (carbonil) foram significativamente maiores apos o termino dos jogos 1 e 2, quando comparadas aos valores pre jogo. Os valores de sulfidrila foram menores apos o termino dos jogos 1 e 2, quando comparados aos valores pre jogo. Nenhuma diferenca foi observada quando comparados os valores apos jogo 1 e o jogo 2 em todos os parâmetros analisados. Coletivamente, os resultados demonstram que a partida de futsal provoca danos musculares e oxidativos. Surpreendentemente, nao houve incremento nos parâmetros avaliados ao final do jogo 2. Devido ao reduzido conhecimento em relacao ao tempo de recuperacao apos uma partida de futsal, acredita-se que este estudo seja de grande importância para os profissionais que trabalham com esse esporte.