Leandro da Silva Borges

Melatonin decreases muscular oxidative stress and inflammation induced by strenuous exercise and stimulates growth factor synthesis.

Strenuous exercise is detrimental to athletes because of the overproduction of reactive oxygen species. Melatonin, a classic antioxidant, has been shown to exhibit beneficial effects regarding intense exercise and tissue repair. In this study, we evaluated the onset and resolution of inflammation in melatonin‐treated and nontreated rats subjected to a strenuous exercise session. We also analyzed the formation of thiobarbituric acid reactive substances (TBARS) and the activities of catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD). Control and treated rats were subjected to exhaustive exercise after a period of 10 days of melatonin treatment (20 mg/dL). Plasma and muscle levels of tumor necrosis factor‐alpha (TNF‐α), interleukin 1 beta (IL‐1β), interleukin 6 (IL‐6), cytokine‐induced neutrophil chemoattractant‐2‐alpha/beta (CINC‐2α/β), l‐selectin, macrophage inflammatory protein‐3‐alpha (MIP‐3α), and vascular endothelial growth factor (VEGF) were measured prior to, immediately after, and 2 hr after exercise. Our data revealed decreases in the muscle concentrations of IL‐1β (35%), TNF‐α (13%), IL‐6 (48%), and TBARS (40%) in the melatonin‐treated group compared with the control group. We also observed decreases in the plasma concentrations of IL‐1β (17%) in the melatonin‐treated group. VEGF‐α concentrations and SOD activity increased by 179% and 22%, respectively, in the melatonin‐treated group compared with the control group. We concluded that muscle inflammation and oxidative stress resulting from exhaustive exercise were less severe in the muscles of melatonin‐treated animals than in the muscles of control animals. Thus, melatonin treatment may reverse exercise‐induced skeletal muscle inflammation and stimulate growth factor synthesis.

Muscle lesions and inflammation in futsal players according to their tactical positions.

Abstract de Moura, NR, Borges, LS, Santos, VC, Joel, GB, Bortolon, JR, Hirabara, SM, Cury-Boaventura, MF, Pithon-Curi, TC, Curi, R, and Hatanaka, E. Muscle lesions and inflammation in futsal players according to their tactical positions. J Strength Cond Res 27(9): 2612–2618, 2013—A futsal players performance depends on his technical and tactical skills but may be improved by a less harmful inflammatory profile that is better adjusted to his tactical position in the game. Thus, the purpose of this study was to characterize muscle lesion and inflammation in futsal players according to their positions in an official match. The participants in this study were 5 goalkeepers (23 ± 1.2 years old, body mass = 74 ± 2.5 kg, height = 178 ± 3.2 cm, body fat = 13 ± 2%, V[Combining Dot Above]O2max = 40 ± 2 ml·kg−1), 8 defenders (21 ± 1 years, body mass = 69 ± 2 kg, height = 174 ± 1 cm, body fat = 10 ± 2%, V[Combining Dot Above]O2max 42 ± 1 ml·kg−1), 8 wingers (22 ± 1 years, body mass = 68 ± 2 kg, height = 169 ± 3 cm, body fat = 11 ± 2%, V[Combining Dot Above]O2max = 48 ± 1 ml·kg−1), and 8 pivots (25 ± 2 years, body mass 71 ± 2 kg, height 173 ± 2 cm, body fat 10 ± 2%, V[Combining Dot Above]O2max 46 ± 2 ml·kg−1). Blood samples were collected from the participants before and immediately after a match. Muscle damage was detected based on CK and lactate dehydrogenase (LDH) activity. The inflammatory status was evaluated by determining C-reactive protein and cytokines (TNF-&agr;, interleukin [IL]-1&bgr;, IL-6, IL-10, and IL-1ra). Goalkeepers showed higher LDH and IL-6 than players occupying other tactical positions, leading to the conclusion that the tactical position of futsal goalkeeper causes more inflammation and muscle damage than other positions. Moreover, this position is usually occupied by athletes with higher body mass and percentage of body fat and lower V[Combining Dot Above]O2max than players in the other positions.

Chronic inflammation and neutrophil activation as possible causes of joint diseases in ballet dancers.

Herein, we investigated the effects of a ballet class on the kinetic profiles of creatine kinase (CK) and lactate dehydrogenase (LDH) activities, cytokines, complement component 3 (C3), and the concentrations of immunoglobulin (Ig), IgA and IgM, in ballerinas. We also verified neutrophil death and ROS release. Blood samples were taken from 13 dancers before, immediately after, and 18 hours after a ballet class. The ballet class increased the plasma activities of CK-total (2.0-fold) immediately after class, while the activities of CK-cardiac muscle (1.0-fold) and LDH (3.0-fold) were observed to increase 18 hours after the class. Levels of the TNF-α, IL-1β, IgG, and IgA were not affected under the study conditions. The exercise was found to induce neutrophil apoptosis (6.0-fold) 18 hours after the ballet class. Additionally, immediately after the ballet class, the neutrophils from the ballerinas were found to be less responsive to PMA stimulus. Conclusion. Ballet class was found to result in inflammation in dancers. The inflammation caused by the ballet class remained for 18 hours after the exercise. These findings are important in preventing the development of chronic lesions that are commonly observed in dancers, such as those with arthritis and synovitis.

Neutrophil Migration and Adhesion Molecule Expression after Acute High-Intensity Street Dance Exercise

The physical demands of street dancing may result in inflammation and changes in leukocyte numbers/function, impairing the health of dancers. Herein, we investigated the effect of street dancing on inflammation, adhesion molecules, and neutrophil function. Fifteen amateur dancers (mean ± SE: age 22.4 ± 1.08 years, BMI 24.8 ± 0.69 kg/m2, and body fat 12.3 ± 1.52%) participated in a single high-intensity street dance class. Blood samples were taken before and after the class. The dance class had no effect on the plasma concentration of CRP, TNF-α, IL-6, IL-10, and IL-8; however, we noted an increase in levels of IL-1β (4.06%) and sL-selectin (17.67%). The dance class resulted in a 12.36% increase in neutrophil counts, while neutrophil CD62L expression and migration were reduced (25.27% and 78.92%, resp.). After the dance class, neutrophil production of IL-8 and TNF-α increased, respectively, by 59.75% and 49.23%, in the control condition, and 43.55% and 32.22%, after LPS stimulation. A single bout of street dancing induced inflammation and reduced neutrophil migration and adhesion molecule expression. These findings may contribute to a better understanding of the susceptibility to infection after acute dance exercise.

The Effect of a Competitive Futsal Match on T Lymphocyte Surface Receptor Signaling and Functions

In this study, the lymphocyte activation status (surface expression of CD95, CD28, CD25, and CTLA-4), lymphocyte number, lymphocyte subpopulations, lymphocyte necrosis and/or apoptosis, and lymphocyte release of reactive oxygen species (ROS) were investigated in blood samples from 16 futsal athletes before and immediately following a competitive match. Lymphocytes were isolated from the blood samples, and the cellular parameters were assessed by flow cytometry. The futsal match induced lymphocytosis and lymphocyte apoptosis, as indicated by phosphatidylserine externalization, CD95 expression, and DNA fragmentation. Additionally, the competitive match induced the necrotic death of lymphocytes. No differences in the percentage of CD4+ and CD8+ T cells or in the T-helper/suppressor profile between before and immediately after the match were observed. Additionally, after the futsal match, the CD95 and CD28 expression levels were decreased, and the lymphocytes spontaneously released higher levels of ROS. Regardless of the origin, the situation-specific knowledge of lymphocyte behavior obtained herein may facilitate the design of strategies to control the processes that result in infection and tissue injury and that subsequently decrease athletic performance.

Grip force control and hand dexterity are impaired in individuals with diabetic peripheral neuropathy

Diabetic peripheral neuropathy (DPN) affects the sensory function of the hands and, consequently, may negatively impact hand dexterity, maximum grip strength (GSMax), and hand grip force (GF) control during object manipulation. The aims of this study were to examine and compare the GF control during a simple holding task as well as GSMax and hand dexterity of individuals with DPN and healthy controls. Ten type 2 diabetic individuals diagnosed with DPN and ten age- and gender-matched healthy controls performed two traditional timed hand dexterity tests (i.e., nine-hole peg test and Jebsen-Taylor hand function test), a GSMax test, and a GF control test (i.e., hold a instrumented handle). The results indicated that individuals with DPN and controls produced similar GSMax. However, individuals with DPN took longer to perform the hand dexterity tests and set lower safety margin (exerted lower GF) than controls when holding the handle. The findings showed that mild to moderate DPN did not significantly affect maximum hand force generation, but does impair hand dexterity and hand GF control, which could impair the performance of daily living manipulation tasks and put them in risk of easily dropping handheld objects.