| Autor: |
Faria, Cláudia Dutra Costantin, Castro, Roberta Borges, Longui, Carlos Alberto, Kochi, Cristiane, Barbosa, Vera Lúcia Perino, Sousa e Silva, Tatiane, Rocha, Mylene Neves, Melo, Murilo Rezende, Monte, Osmar |
| Předmět: |
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| Zdroj: |
Hormone Research in Paediatrics; May2010, Vol. 73 Issue 6, p458-464, 7p, 2 Charts, 2 Graphs |
| Abstrakt: |
Background/Aim: Healthy individuals present variable responses of the hypothalamic-pituitary-adrenal (HPA) axis induced by different patterns of physical training. The aim of this study was to evaluate whether prolonged low-grade physical training influences the HPA axis and also glucocorticoid receptor-α (GRα) mRNA levels in mononuclear cells of obese adolescents. Methods: We studied 19 patients with BMI above the 95th percentile (male:female ratio 7:12) aged from 9.5 to 15.5 years. Patients underwent a 12-week physical exercise program. Before and after exercise, in vivo glucocorticoid sensitivity was determined by employing a very-low-dose intravenous dexamethasone suppression test, and in vitro GRα mRNA levels were evaluated by quantitative real-time PCR. Results: After exercise there was a trend to reduce the in vivo glucocorticoid sensitivity (p = 0.071) and a significant increase in GRα mRNA levels (p = 0.025). Conclusion: For this subset of obese adolescents, prolonged low-grade physical training tended to reduce glucocorticoid sensitivity. The discrepancy of cortisol response to dexamethasone and the GRα mRNA measurement suggest a post-receptor phenomenon or should be related to target tissue-specific differences in glucocorticoid sensitivity. Future studies should address the adaptive GRα mRNA during different exercise protocols, and also the correlation of pituitary sensitivity with glucocorticoid target tissue sensitivity. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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