Aim: The aim of the study was to investigate the association between PPAR-γ2 Pro12Ala polymorphism and laboratory characteristics of carbohydrate metabolism in children and adolescents with obesity. In addition, serum levels of tumor necrosis factor (TNF)-γ, and soluble form of its receptors (sTNFR1 and sTNFR2) were assessed. Methods: In a cross-sectional study, 79 obese children and adolescents of Caucasian origin were investigated. PPAR-γ2 Pro12Ala polymorphism was determined using polymerase chain reaction - restriction fragment length polymorphism technique. Serum levels of TNF-γ, sTNFR1 and sTNFR2 were measured by enzyme amplified sensitivity immunoassay. Results: The minor Ala allele frequency was found to be 14.56 % in our cohort. No significant differences in age, BMI, waist circumference, blood pressure, serum lipid, uric acid, TNF-γ, sTNFR1 and sTNFR2 values were found between carriers of the Ala allele (Pro/Ala and Ala/Ala; n = 21) vs. homozygous carriers of the Pro allele (Pro/Pro; n = 58). However, post-challenge (120 min) plasma glucose and insulin values were significantly lower in Ala allele carriers vs. homozygous Pro allele carriers (6.56 ±0.26 vs. 7.36 ±0.25 mmol/L and 65.9±13.8 vs. 111.8±20.7 μU/mL, respectively; p<0.05); while no significant differences were found at fasting state. Conclusions: The association between PPAR-γ2 Pro12Ala polymorphism and glucose metabolism is already present in children and adolescents with obesity who might be at the very beginning of the natural course of type 2 diabetes. At this stage, higher insulin sensitivity can be detected in Ala allele carriers compared to homozygous Pro subjects at post-challenge but not in fasting state; however, the TNF-system seems not to be involved in the alteration of glucose homeostasis due to PPAR-γ2 Pro12Ala polymorphism.
ASJC Scopus subject areas
- Pediatrics, Perinatology, and Child Health
- Endocrinology, Diabetes and Metabolism