Articles : Influence of the UCP2 Gene Polymorphism on Obesity Indices, Cardiorespiratory Fitness, and Obesity-related Metabolic Syndrome Markers in Non-obese and Obese Subjects

Journal of Exercise Nutrition & Biochemistry 2004;8(3):347-354.

Abstract

The purpose of the current study was to compare anthropometrics. obesity indices, cardiorespiratory fitness, and obesity-related metabolic syndrome markers between non-obese group (n = 35) and obese group (n = 32) according to the UCP2 gene I/D polymorphism. Body mass index of ≥25 kg/m² along with ≥20% body fat were used as the criteria for obesity classification. Apparently healthy subjects aged between 20-30 years were recruited via flyers and local advertisements on a campus news letter. Following an overnight fasting, the subjects visited to our laboratory three times on separate days. On the first visit, anthropometrics and body composition were measured. On the second visit, blood samples taken from an antecubital vein were used for the determination of the UCP2 genotype, blood lipids, glucose, lactate levels. VO₂max and 1 minute recovery heart rate were measured on a motor-driven treadmill using the Bruce protocol. On the final visit, resting metabolic rate was determined via an indirect calorimetry by using a metabolic cart. The result of the current study showed significant differences in resting DBP (p=.028), TG/HDL-C ratio (p = .027), and fasting TG concentration (p = .052) between the genotypes in the obesity group, while no significant genotype-specific differences were found in any of the measured variables in the non-obese group (p＜.05). Stepwise multivariate regression analysis showed that 1) UCP2 genotype explained up to 31.1% of individual variation in resting DBP, 2) both UCP2 genotype and body fat explained up to 31.9% of individual variation in TG/HDL-C ratio, and 3) WHR explained 27.1% of individual variation in fasting TG concentration. In conclusion, the current findings suggest that the UCP2 DID genotype is associated with resting DBP and blood TG concentration in the obese group of the study population but not in the non-obese group, indicating a possible interaction between the UCP2 gene and obesity in the development of the obesity-related metabolic syndrome.

Key Words: UCP2 gene, obesity, metabolic syndrome markers