Increased Glypican-4 Levels Are Associated with Obesity in Adolescents

Abstract

Background: Glypican-4 is an adipose tissue-originated cytokine which enhances insulin signaling through direct interaction with the insulin receptors. Objectives: The aim of this study was to analyze the relationship between obesity and serum glipican-4 levels in adolescents. Methods: Our study was carried out on 80 volunteer adolescents, 49 were obese patients and 31 were healthy normal weight control cases. The adolescents with a body mass index (BMI) of 95% percentile and over were defined as obese in terms of age and sex. The Enzyme-Linked Immuno Sorbent Assay kit was utilized for the assessment of Glypican-4 in serum. Laboratory assays (glypican-4, glucose, urea, creatinine, AST, ALT, total cholesterol, triglyceride, HbA1c, insulin, HOMA-IR), age, sex and BMI were compared amidst the groups. Correlations between glypican-4 levels and laboratory factors were analyzed in the obese adolescent group. Results: The average age of the research participants was 13.2 ± 1.8 years. The mean BMI was 27.1 ± 5.1 kg/m2. Of the 49 obese adolescents, 41 were insulin resistant, and 8 did not have insulin resistance. The levels of glypican-4, BMI, AST, ALT, HbA1c, triglyceride, HOMA-IR and insulin were notably higher in the obese group than the control group (P < 0.05). In obese group, no statistically remarkable relationship was found between glypican-4 levels and other parameters (P > 0.05). Conclusions: We found high serum glypican-4 levels in obese adolescents. We suggest that glypican-4 levels may be increased in order to reduce insulin resistance in obese adolescents.