Research On The Influence Of Exercise On Glucolipids Metabolism And Visfatin In Obese Children And Adolescents As Well As Visfatin Gene Polymorphism

一、The Purpose and Significance of ResearchObesity is closely related to glucose and lipid metabolism disorders in children and adolescents.At present,a systemic research about the exercise-induced changes of glucose and lipid metabolism,erythrocyte membrane lipids and endogenous regulator in obese children and adolescents is lacked.In this research the changes of Plasmaglucose, Plasmalipids and erythrocyte membrane lipids of different obesity degrees children and adolescents before and after a 4-week closed aerobic exercise to lose weight with small and medium intensity and long term time were analyzed. Visfatin,a new adipocytokine,being the main line in this research,the regulation of it combined endogenous regulators such as leptin,IL-6 to the exercise-induced changes of glucose and lipid metabolism in obese children and adolescents was studied.Meanwhile,the association between visfatin SNPs and levels of glucose and lipid metabolism was investigated.This research was designed to provide a scientific theory foundation for exploring the mechanism of exercise to lose weight .二、The Contents and Experimental Results of ResearchThe whole study is composed of four parts with seven experiments.The first part(experiment 1) is to study comparatively six different indirect evaluation of body fat ,and try to find out a relatively appropriate indirect method to estimate body fat mass in 88 obese children and adolescents involved in this research.Pearson correlation and Multiple Stepwise regression analysis were applied to compare the results among BIA,Lohman,,Brozek,,Siri,,Slaughter,and Chinese prediction equations.The results showed that compared to the prediction equations through various types of skin fold thickness,it seemed that BIA could be more accurately used to estimate body fat mass in obese children and adolescents in this research. According to percentage of body fat measured by BIA,88 obese children and adolescents were divided into mild, moderate and severe obesity group.The determination of indirect evaluation method of body fat rate provided a necessary premise for the follow-up study in this research.The second part study(experiment 2,3) focused on the influence of exercise-induced weight loss on plasmaglucose,plasmalipid,erythrocyte membrane lipid and related ATPase activity in obese children and adolescents.The main results were as follows:①PS exposure was significantly higher in the severe obesity group than in the other two groups(P≤0.05),while plasma level of HDL was significantly different only between the mild obesity group and the severe one.②A significant increase in Na+K+-ATPase activity after exercise intervention(P≤0.05) while no significant increase in Ca2+Mg2+-ATPase activity.A downward trend in PS exposure on erythrocyte membrane after exercise intervention was observed but there was no significant difference.③plasmaglucose and lipids index were correlated to the indicators of human morphology especially WC before exercise intervention,and exercise-induced changes in body fat rate was also significantly correlated to the changes in plasmalipids.The third part study(experiment 4,5) focused on the regulation of visfatin combined endogenous regulators such as leptin,IL-6 to the exercise-induced changes of glucose and lipid metabolism in obese children and adolescents.The main results were as follows:①Pre-exercise plasma visfatin was significantly positively correlated with HDL,while no significant correlation with glucose metabolism.②Pre-exercise plasma visfatin was significantly positively correlated with other adipocytokines such as leptin and IL-6. The significantly increase of exercise-induced plasma visfatin was positively correlated with that of leptin.③The rise margin of visfatin was consistent to the decline margin of human morphology indicators and glucose metabolism among the different obese groups.The fourth part study(experiment 4,5) focused on investigating the single nucleotide polymorphisms(SNPs) of RS5974456 and RS4730153 in visfatin gene in obese children and adolescents of Han population,and analyzing its relation to the exercise-induced glucose ,lipid metabolism and obesity-related variables changes. The main results were as follows:①14 obese children and adolescents were visfatin RS4730153 A/G genotype and the frequencies was 15.9%,but only one was RS5974456 G/T genotype.②The indexes of glucose and lipid metabolism before and after aerobic exercise showed significant changes.TG levels before exercise was significantly different between the different genotypes subjects(GG: 1.40±0.74mmol / L,AG: 1.86±1.11mmol / L,respectively.P =. 050).HOMA-βafter exercise was significantly different between the different genotypes subjects(GG: 220.50±178.81, AG: 332.23±207.90,respectively.P =. 050).三、Conclusion:①Obesity,especially abdominal obesity in children and adolescents is closely related to dyslipidemia and reduced insulin sensitivity.The abnormal PS exposure maybe take place earlier than the change in plasma lipids.②Aerobic exercise intervention can not only reduce the total amount and distribution of body fat in obese children and adolescents,but also regulate glucose and lipid metabolism through the improvement of erythrocyte membrane Na+K+-ATPase activity, insulin sensitivity, adipocytokine level such as visfatin.However,the improvement of erythrocyte membrane lipids lags to that of plasmalipids.③A strong correlation exists between visfatin and other adipocytokine especially leptin to achieve the regulation of glucose and lipid metabolism under the intervention of exercise in obese children and adolescent.④The SNPs of visfatin RS4730153 variation was found in obesity children and adolescents from Chinese Han population.Homozygous GG was possibly involved in glucose and lipid metabolism by reducing TG levels and improving exercise-induced HOMA-βsensitivity.