ABSTRACT
BACKGROUND: Balanced diet and scientific exercise are generally accepted as safe, effective and economical body mass management interventions. However, exercises sometimes increase the appetite of dieters. Combining hypoxic environment stimulation with aerobic exercise intervention may achieve the best effect on weight loss. As the central part of the body that regulates food intake and energy balance, the hypothalamus is concerned about the relationship between its regulating factors and the pathogenesis of obesity. OBJECTIVE: To observe the levels of nesfatin-1 and ghrelin in the hypothalamus of obese rats, so as to explore the neuroendocrine mechanisms of feeding and body mass by hypoxia and/or exercise. METHODS: Sixty Sprague-Dawley male rats with alimentary obesity were divided into six groups: quiet group, aerobic exercise group, 16.3% hypoxia quiet group, 16.3% hypoxic exercise group, 13.3% hypoxia quiet group and 13.3% hypoxic exercise group. A low-oxygen generator was used to create hypoxia environment at a volume fraction of 16.3% oxygen and 13.3% oxygen. Under hypoxia environment, the rats were continuously fed with high-fat food, and subjected to a treadmill exercise, 20 m/min (0° slope), 40 min/d, 5 days per week for 8 continuous weeks. Body mass and food intake were recorded, and Lee’s index was calculated. Levels of nesfatin-1 and ghrelin in the rat hypothalamus were measured after intervention by means of ELISA kit. RESULTS AND CONCLUSION: (1) The body mass and Lee’s index after intervention: the effect of simple hypoxic environment stimulation on body mass and Lee’s index of rats was not as obvious as that of simple aerobic exercise stimulation. When hypoxic environment was combined with exercise, the effect was better than that of single stimulation. (2) Daily food intake during the intervention period: The daily food intake remained stable in the normoxic quiet group, and decreased in all other groups decreased, especially in the 16.3% hypoxic exercise group and 13.3% hypoxic exercise group. (3) Levels of nesfinin-1 and ghrelin in the hypothalamus: hypoxia combined with exercise could change nesfinin-1 levels in the hypothalamus of rats, and the nesfinin-1 level was highest in the 13.3% hypoxic exercise group. Exercise or hypoxia alone could affect the ghrelin level in the hypothalamus of rats, and the effect of single exercise stimulation was better than that of single hypoxia stimulation. Moreover, the combination of exercise and hypoxia made a further reduction in the ghrelin level. (4) Bivariate analysis of variance: Body mass and ghrelin level were affected by exercise; body mass, Lee’s index and food intake were affected by O2 concentration; and body mass, nesfinin-1 and ghrelin levels were affected by exercise×O2 concentration. These findings indicate that 8-week hypoxic exercise may decrease the rats’ food intake, inhibit the increase of body mass and reduce the Lee’s index by regulating nesfinin-1 and ghrelin levels in the hypothalamus, but the specific mechanism is not clear.
ABSTRACT
El deporte exige de quienes lo practican una adaptación, entrenamiento y buen estado físico. El objetivo del trabajo fue estudiar en suero/plasma de individuos jugadores de fútbol de élite (n=32) y no entrenados (n=16), los perfiles hematológico, endocrinológico y de química clínica, relacionar los hallazgos bioquímicos con la fisiopatología deportiva y evaluar la probable implicancia clínica de los resultados. De acuerdo con los resultados obtenidos se observó disminución significativa en: hematocrito, hierro, plaquetas y bilirrubina (expansión plasmática fisiológica); magnesio (consumo enzimático); y proteínas y glucemia (incremento del metabolismo energético y recambio proteico). No se detectaron cambios significativos en el perfil endocrinológico (TSH disminuida, mayor eficacia de la hormona) y perfil lipídico (aumento de HDL y disminución de LDL; efecto protector de las lipoproteínas). Se observó un aumento significativo en: calcio (mayor disponibilidad); urea (metabolismo proteico aumentado); y aldolasa y creatinquinasa (lisis fibra muscular entrenada). Se concluye que la creatinquinasa es el marcador de pertenencia al grupo de élite; se debería implementar un valor de referencia diferente para esta población de deportistas ya que el deporte es objeto de estudio del laboratorio bioquímico; y la implementación de los conocimientos científicos en forma práctica y adecuada permite ayudar al profesional médico deportólogo a tomar decisiones oportunas y acertadas.(AU)
Sports demand from those who practice it, adaptation, training and a good physical condition. The objective of the work was to study in serum/plasma of trained people (elite football players, n=32) and untrained people (n=16) the clinical laboratory, haematological, and endocrinal profiles; 2) to relate the biochemical findings to sports physiopathology; 3) Assess the probable clinical implication of the results obtained. The results detained showe a significant decrease in hematocrit, iron, platelets and bilirrubin (physiological plasma expansion); magnesium (enzymatic consumption); proteins and glycemia (increase in energy metabolism and protein change). Without significant changes in endocrinological profile (decreased TSH, greater hormone efficiency); and lipid profile (increased HDL and decreased LDL; lipoprotein protector effect).Significant increase: calcium (more availability); urea (increased protein metabolism); and aldolase y creatinkinase (lysis of trained muscle fibre). Creatinkinase is the scoreboard of belonging to the elite group. It should be a different reference value for this group. -Thus, sport is object of study at the clinical laboratory; and implementation of the scientific knowledge in a practical and suitable manner enables the health professional to make relevant and right decisions.(AU)
O esporte exige daqueles que o praticam uma adaptaþÒo, treinamento e bom estado físico. O objetivo do trabalho foi estudar em soro/plasma de indivíduos jogadores de futebol de elite (n=32) e nÒo treinados (n=16), os perfis hematológico, endocrinológico e de química clínica, relacionar os achados bioquímicos com a fisiopatologia esportiva, e avaliar as possíveis implicaþ§es clínicas dos resultados. De acordo com os resultados obtidos se observou diminuiþÒo em hematocrito, ferro, plaquetas e bilirrubina (expansÒo do plasma fisiológico), magnésio (consumo enzimático); e proteína e glicemia (aumento do metabolismo energético e recÔmbio proteico). NÒo foram observadas alteraþ§es significativas no perfil endocrinológico (TSH diminuído, maior eficácia do horm¶nio); e perfil lipídico (aumento de HDL e diminuiþÒo de LDL; efeito protetor das lipoproteínas). Observou-se-aumento significativo em: cálcio (maior disponibilidade); ureia (metabolismo proteico aumentado); e aldolase e creatina-quinase (lise fibra muscular treinada). Conclui-se que a creatina-quinase é o marcador de pertenþa ao grupo de elite. Deveria ser implementado um valor de referÛncia diferente para esta populaþÒo de esportistas visto que o esporte é objeto de estudo do laboratório bioquímico; e a implementaþÒo dos conhecimentos científicos em forma prática e adequada permite ajudar o profissional médico esportólogo a tomar decis§es oportunas e certas.(AU)
