3. Poster Presentations
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©Journal of Sports Science and Medicine (2009) Suppl. 11, 1-198 79 http://www.jssm.org 3. POSTER PRESENTATIONS Roles of skeletal muscles impairment and brain oxygenation in limiting oxidative metabolism during exercise after bed rest 1 3 2 2 3 3,4 Porcelli S , Marzorati M , Lanfranconi F , Vago P , Cerretelli P and Grassi B 1 2 Scuola di Specializzazione in Medicina dello Sport, Univ. Milano, Italia, Dipartimento di Scienze e Tecnologie 3 4 Biomediche, Univ. Milano, Italia, Istituto Bioimmagini e Fisiologia Molecolare, CNR, Milano, Italia, Dip. Scienze e Tecnologie Biomediche, Univ. Udine, Italia “Central” and “peripheral” limitations to oxidative metabolism during exercise were evaluated on 10 young males following a 35-day horizontal bed rest (BR). Incremental (IE), moderate- and heavy-intensity constant-load exercises (CLE) were carried out on a cycloergometer before and after (1-2 days after subjects rose from bed) BR. Pulmonary gas exchange, heart rate (HR) and cardiac output (Q) (by impedance cardiography), skeletal muscle (vastus lateralis) and brain (frontal cortex) oxygenation (by near-infrared spectroscopy) were determined. After BR, “peak” (values at exhaustion during IE) workload (Wpeak), peak O2 uptake (VO2peak), peak stroke volume, Qpeak and peak skeletal muscle O2 extraction were decreased (-18%, -18%, -22%, -19%, -33%, respectively), whereas HRpeak was unaffected. The gas exchange threshold was ~60% of VO2 peak both before and after BR. The efficiency of cycling (ratio between external mechanical power output and oxidative energy output) was unaffected by BR. At the highest workloads brain oxygenation data suggest an increased O2 extraction, unaffected by BR. VO2 kinetics during CLE (same % of Wpeak before and after BR) were slower (time constant of the “fundamental” component 31.1±2.0 s before vs. 40.0±2.2 s after BR). The amplitude of the “slow component” was unaffected (at the same % of Wpeak) by BR, thus it would be greater after BR at the same absoluteW. Skeletal muscles contribute to the impairment of oxidative metabolism during exercise after BR. The reduced capacity of peak cardiovascular O2 delivery did not determine a “competition” for the available O2 between skeletal muscles and brain. Effect of a selected endurance training program on blood CD4, CD8, and IgA active females Hojat Allah Nikbakht 1, Abasali Gaieni 3 and Farah Nameni 2 1 2 Azad Islamic University. Olom va Tahghighat, Islamic Azad University Varamin ¨C Phishva Branch, 3Tehran University OBJECTIVE This study examined the effect of exercise on the percent blood lymphocytes T (T helper and suppressor) and immunoglobulin A. Studies have demonstrated that strenuous physical exercise in humans is accompanied by changing in circulating levels of lymphocytes. The purpose of this study was to examine the effect of eight weeks endurance training program on blood CD8, CD4 and IgA active females. METHODS Method twenty recreational active women participated in the study. Subjects were assigned in one of two experimental group (n=10) (age: 21.6±1.71years, height: 161.45±2.71cm. weight: 57.25±6.99 kg. and VO2max 34.18±2.ml.kg¯¹.min¯¹) and control group (n=10), (age: 24.25±4.30years, height: 159.81±4.86cm, weight: 54.69±3.82kg. and VO2max: 36.1±3.79 ml.kg¯¹.min¯¹) groups. Blood sampling were obtained before and after an exhaustive bout of exercise sessions. Lymphocyte subsets were determined by flow cytometry using monoclonal antibodies for T-helper (CD4+), and T-suppressor (CD8+) lymphocytes. Training group participated in an 8-week incremental endurance training program. After training, blood sample were obtained before and after an exhaustive bout of exercise. Data was analyzed using ANOVA test. RESULTS There were increased in the percentage T-helper lymphocytes levels in 2 groups, decreased T - suppressor levels and increased IgA in 2 groups. There were no significant changes in IgA concentration but CD4 and CD4 / CD8 increased and CD8 decreased significantly (P<0.05). DISCUSSION & CONCLUSION It was concluded that endurance training may induces changes in lymphocyte subsets but not in suppression of immune function after exercise. Elevated levels of immunoglobulins, especially IgA can be measured in the plasma of athletes after exhaustive long term exercise.We conclude that endurance training may result in significant alteration in IgA and T lymphocyte number , but their actual significant for immunity is seen controversially. KEY WORDS immune system, exercise, active female ©Journal of Sports Science and Medicine (2009) Suppl. 11, 1-198 80 http://www.jssm.org The effect of 8 weeks endurance exercise on cytokines Hojat Allah Nikbakht 2, Abasali Gaieni 3 and Farah Nameni 1 1 2 3 Islamic Azad University Varamin – Phishva Branch, Islamic Azad University, olom va Tahghighat, Tehran University OBJECTIVE Several studies have demonstrated that strenuous physical exercise in humans is accompanied by an increase in circulating levels of inflammatory cytokines. Exercise is the strongest stress to which the body is ever exposed he body response to this stress through a set of physiological changes in its metabolic hormonal and immunological systems. In this study responses of the immune system to endurance exercise have been investigated. METHODS18 healthy active females, university students participated in this study. Subjects were divided in 2 groups, experimental group (age: 21. 60 ± 0.54 years, weight: 57.25 ±2.21 kg, height: 161.45 ± 0.86 cm, body mass: 21.99 ± 0.8 kg) and control group (age: 24.25 ± 1.52 years, weight: 54.69 ±1.34 kg, height: 156.87 ± 1.71 cm, body mass: 21.40 ± 0.4 kg). After physical examinations of the 2 groups, heart rates and VO2max with the use of Bruce test were determined. The first group was subjected to endurance exercise at a heart rate 60- 75, for 8 weeks, 3 days a week, 30 min. a day. The second group did not have exercise. Pre –exercise and post 8 weeks exercise, venous blood samples were taken from each group. Plasma levels of several cytokines namely interleukins (IL) IL1 and IL 6 and TNFα were determined by ELISA. Statistical analyses, t-test and ANOVA used for measurement IL1, IL6 and TNFα response. RESULTS Means showed the level of IL1 not changed in experimental group but decreased in control group, the level of IL6 not changed in experimental and control groups, the level of TNFα decreased in 2 groups. T test and ANOVA showed the IL1, IL6 and TNFα response were not significantly. The percentage of lymphocytes expressing intracellular IL1, IL6 and TNFα were not higher in the experimental group than in control group, and it was similar to the value estimated in the 2 groups. DISCUSSION & CONCLUSION In conclusion the response of the cytokines (IL1 and IL 6 and TNFα) to exercise depends on exercise intensity and duration. Recent studies show that several cytokines can be detected in plasma during and after strenuous exercise but in this study cytokines did not change, because the selected endurance training was not very strenuous and did not affect on increasing or suppressing of interleukins and TNFα function or proliferation. KEY WORDS exercise, IL1, IL6, TNFα Human growth hormon effects on the immune system: an in vitro study Paolo Borrione, Loredana Grasso, Attilio Parisi, Luigi Di Luigi and Fabio Pigozzi University of Rome “Foro Italico”, Department of Health Sciences, Piazza Lauro de Bosis 15, 00194 Rome, Italy OBJECTIVE Several evidences underline the increased abuse of recombinant human growth hormone (rhGH) among athletes meanly because of its anabolic properties. RhGH exerts a pleiotrophic activity at cellular level which stimulates the proliferation of different cell types through the direct or in direct IGF-1 action. Previous studies demonstrated that, on lymphocytes, rhGH binding to its receptor induces an over-expression of proteins involved in cell proliferation (e.g. Cyclin E, c-myc) and the inhibition of the expression of genes involved in the apoptotic processes (e.g. Bcl-2, Bcl-XL). The aim of the present study was to evaluate the effect of rhGH, alone or in combination with corticosteroid, on cultured lymphocytes in order to analyse the efficiency of the immune system (activation, apoptosis, alloreactivity) following rhGH exposure. METHODS PBMC were obtained by density gradient centrifugation of heparinized venous blood collected both from healthy and allergic donors. RhGH, was used at the following concentrations: 100 ng/ml, 200 ng/ml, 300 ng/ml, 400 ng/ml e 600 ng/ml. Apoptosis was induced with Methylprednisolone (MP) 1,5 µM/l or incubating the cells in the pre- sence of 1% fetal calf serum (FCS). Mixed lymphocyte cultures were carried out in order to analyze the alloreactivity. Flow cytometry was performed with the use of FACS Calibur cytometer Becton Dickinson. RESULTS Following 24 hors of incubation, lymphocyte spontaneous apoptosis was significantly increased (6.39±0.24 vs 12.55±0.28). On the contrary, MP induced apoptosis was unaffected by rhGH treatment (14.95±1.87 vs 15.78±0.22). After 3 hours of incubation, rhGH treatment increased the co-expression of the activation antigens CD38/HLA-DR on CD3/CD8 positive cells only (8.41±0.57 vs 12.77±0.68). After 24 hours of incubation, rhGH treatment was able to modify the CD38/HLA-DR co-expression on CD3/CD4 positive cells too (8.80 ± 0.36 vs 19.84±2.30). RhGH treatment was unable to modify the percentage of Th2 cells on samples obtained both from healthy and allergic subjects (1.03± 0.09 vs 1.14 ± 0.14 and 1.69± 0.16 vs 1.9± 0.21 respectively). RhGH treatment was unable to modify the number and the size of cell clusters when mixed lymphocytes cultures are concerned. DISCUSSION & CONCLUSION RhGH in vitro treatment exerts the following effects on lymphocytes: - increases the spontaneous apoptosis - does not modify the induced apoptosis - increases the co-expression of the activation antigens CD38/HLA-DR which lasts for at least 48 hours - does not increase the alloreactivity - does not modify the composition of the CD4+ sub-populations Th1 and Th2 KEY WORDS Growth hormon, lymphocyte, immune system, flow cytometry ©Journal of Sports Science and Medicine (2009) Suppl.