Molecular Mechanism And Change Of Oxidative Status Intervened By Aerobic Exercise And Diet Restriction In Obese Adolescent

Object:Oxidative stress plays critical roles in the pathogenesis of obese related diseases,but the changing of glucose and lipids metabolism under the oxidative stress induced by NAPDH oxidase(NOX) in obese adolescents is still unclear.The mechanism of exercise and diet restriction,two effective interventions widely used in weight reduced program,on changing of body status,glucose and lipids metabolism, and oxidative stress in obese adolescents is defect.The purpose of this project is to observation the effectiveness of exercise and diet restriction interventions on changing of body configuration and composition,heart and pulmonary functions, glucose and lipids metabolisms,and further changing of oxidative stress induced by NOX.Method:93 overweight or obese adolescents according BMI criteria were divided into diet restriction group(N=22),exercise group(N=25),exercise and diet restriction group(N=29),and positive control group(N=17);there were no significant differences in BMI among these groups.31 subjects with normal BMI and matched age and sex were selected as normal control group.In diet restriction,daily caloric was given according 80%and 70%of ideal total energy requirement in overweight and obese adolescents respectively,and protein,fat,and carbohydrate were given in 15%to 20%,25%to 30%,and 50%to 60%pro rate.Training programme consisted of 60 minutes of activity at an intensity of approximately 40% to 60%VO_2max monitoring by heart rate,4 times a week.All subjects were measured body configuration,composition,vital capacity(VC) and maximal heart rate(HRmax) after exercise and motor ability;the serum glucose and lipids,biomarkers of oxidative stress,and expression and activation of NOX subunits in part of subjects were also detected before and after 10 weeks intervention period.Result:(1) Comparing to normal controls,the body weight,BMI,percentage of body fat,amount of muscle were significantly higher,and function of heart and pulmonary and motor ability were significantly lower in overweight and obese adolescents.(2) The average serum levels of glucose and lipids were in normal range in all subjects.The serum levels of fasting and 2 hours glucose,and corresponding insulin secretion were higher,the serum levels of TC and LDL-c were higher and HDL-c was lower in overweight and obese adolescents comparing with normal controls.(3) The ROS in monocytes and serum levels of MDA and protein carbonyl were higher,SOD was lower in overweight and obese adolescents accompany by the increase expression of Racl and decrease expression of p67phox,activation of NOX.(4) Diet restriction is more effective in weight loss,and exercise can markedly decrease the visceral adipose tissue,improve the heart and pulmonary function and motor ability.Exercise with diet restriction can increase the amount of muscle.(5) The decrease of serum level of glucose is related with the weight loss during diet restriction,and the decreases of serum levels of TC and LDL-c are accompany by the improvement of central obesity during exercise.(6) After intervention,the level of ROS in monocyte and MDA and protein carbonyl in serum were markedly decreased; the differences of ROS and MDA,expression of Racl and p67phox between obese and normal controls were disappeared.The changes of oxidative stress were related with the decrease of total fat mass.(1) There are increased oxidative stress and trend of insulin resistance in overweight and obese adolescents.(2) Exercise and diet restriction can effectively decrease the multiple risk factors of obese related diseases,improve the physical quality.(3) The effectiveness of exercise and diet restriction may be related with the decrease of system oxidative stress.