ABSTRACT
BACKGROUND/OBJECTIVES: In recent years, oxytocin (OXT) and polymorphisms in the oxytocin receptor (OXTR) gene have been reported to play roles in obesity pathogenesis. However, there was no study evaluating OXTR gene variants in childhood obesity. The aim of the study was to investigate the relation of OXTR gene polymorphisms and serum OXT levels with metabolic and anthropometric parameters in obese and healthy adolescents. SUBJECTS/METHODS: The study was a multi-centered case-control study, which was conducted on obese and healthy adolescents aged between 12 and 17 years. Serum OXT and leptin levels were measured, and OXTR gene variants were studied by qPCR (rs53576) and RFLP (rs2254298) methods. RESULTS: A total of 250 obese and 250 healthy adolescents were included in this study. In the obese group, serum OXT level was lower and leptin level was higher than the control group. In the obese group, frequencies of homozygous mutant (G/G) and heterozygous (A/G) genotypes for rs53576 polymorphism were higher than the control group. Homozygous mutant(G/G) and heterozygous (A/G) genotypes for rs53576 polymorphism were found to increase the risk of obesity compared to the wild type (A/A) genotype [OR = 6.05 and OR = 3.06; p < 0.001, respectively]. In patients with homozygous mutant (G/G) and heterozygous (A/G) genotype for rs53576 polymorphism, serum OXT levels were lower than the wild type (A/A) genotype. In the obese group, hyperphagia score was higher than the control group and correlated negatively with serum OXT level. CONCLUSIONS: This study revealed that low serum OXT level, which is associated with hyperphagia may be an underlying cause for obesity in adolescents. For rs53576 polymorphism of the OXTR gene, obesity risk is higher in patients with homozygous mutant(G/G) and heterozygous(A/G)genotypes.
Subject(s)
Hyperphagia/complications , Oxytocin/analysis , Pediatric Obesity/complications , Polymorphism, Genetic , Receptors, Oxytocin/genetics , Adolescent , Case-Control Studies , Female , Humans , Hyperphagia/blood , Male , Oxytocin/blood , Pediatric Obesity/bloodABSTRACT
OBJECTIVES: Obesity is often the result of a high-calorie and unbalanced diet for a long time and can sometimes be associated with hyperphagia and eating disorders. Neurotensin (NT) is an anorexigenic peptide, which is secreted from the central nervous system and intestines, and increases intestinal fat absorption. In the literature, conflicting results regarding serum NT level in obesity and the relation of NT with metabolic parameters were reported. Besides, there is no data regarding the relation of NT with eating disorders or food preference in obese individuals. We aimed to evaluate the relation of serum NT level with metabolic parameters, hyperphagia, binge eating disorder (BED) and food preference in obese adolescents. METHODS: The study included 65 obese adolescents and 65 healthy controls. Anthropometric measurements, biochemical analyzes and body fat analyzes were performed in all cases. Hyperphagia score, presence of BED and three-day food intake records were also evaluated. RESULTS: NT level was significantly higher in obese adolescents than in controls and it was not associated with metabolic parameters, hyperphagia or food preference. In the obese group, NT level was not significantly different according to the presence of BED. CONCLUSIONS: Serum NT level is high in obese adolescents; however, it is not associated with metabolic parameters, hyperphagia, BED or food preference.
