Dyslipidemia, insulin resistance and dietary fat intake in obese and normal weight adolescents: the role of uncoupling protein 2 -866G/A gene polymorphism.

Abstract

Obesity in adolescents has been associated with increased cardiovascular risk factors such as dyslipidemia and insulin resistance. Several factors have been proposed to be associated with cardiovascular risk factors in adolescents including dietary habit, physical activity and genetic. This study was aimed to evaluate the interaction between genetic variation and dietary intake on cardiovascular metabolic risk factors in obese and normal weight adolescents. The UCP2 gene was chosen because it was previously correlated with dietary intake and cardiovascular risk factors. This study is a case control study done in 10 senior high school in Yogyakarta. Subjects were obese and normal weight adolescents taken from an obesity screening with age ranged between 16 and 18 years old. Dyslipidemia was observed by measuring total cholesterol, triglyceride, LDL dan HDL level while insulin resistance was determined by calculating fasting glucose and insulin level. Lipid profile, glucose and insulin level were measured after 8 hours of fasting. UCP2 -866G/A gene polymorphism were determined using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results show that obese adolescents had significantly higher blood pressure, total cholesterol, LDL, triglyceride, insulin level and lower HDL level than their normal weight counterparts (all p<0.001). In obese adolescents, UCP2 -866G/A was associated with blood pressure (p=0.025), total cholesterol level (p=0.025), LDL (p=0.024) level and HOMA IR (p<0.001) but not with dietary fat intake (p=0.386). Additionally, subjects with UCP2 -866G/A gene polymorphism and high dietary fat intake had lower risk on obesity compared to those without UCP2 -866G/A gene polymorphism and low dietary fat intake. We conclude that the UCP2 -866G/A was associated with dyslipidemia, insulin resistance in obese adolescents. Additionally, we also observed the interaction between UCP2 -866G/A gene polymorphism and dietary intake on the risk of obesity.