Fat Cell Size and Adipokine Expression in Relation to Gender, Depot, and Metabolic Risk Factors in Morbidly Obese Adolescents

Objective: To understand the regulation of adipocyte size and adipokine expression in relation to gender, anatomic location, adiposity, and metabolic risk factors in adolescents with morbid obesity. Methods: Adipocyte size and adipokine expression in paired abdominal subcutaneous (SAT) and omental (VAT) surgical adipose tissues were related to gender, anatomic location, adiposity, and metabolic risk factors in a group of morbidly obese adolescents. Results: Significant depot-and/or gender-related differences in adipocyte size and adipokine expression were detected. Adjusted for body mass index, adipocyte size in both depots was larger in males than in females and was a major predictor of mRNA levels of leptin, plasminogen activator inhibitor-1, and adiponectin. Gender, but not adipocyte size, was significantly correlated with proinflammatory cytokine expression. Body mass index and waist circumference were correlated positively with VAT adipocyte size and negatively with SAT adipocyte size. VAT adiponectin and interleukin-6 expression levels were major predictors of high-density lipoprotein cholesterol concentrations, independent of gender, adiposity, and insulin sensitivity. Conclusions: Adipose tissue morphology and function in obese adolescents are influenced by gender and anatomic location; the pattern of gender-and depot-related differences in adipocyte size and adipokine expression suggests that adolescent males, relative to the females, are at increased risk for obesityrelated metabolic comorbidities.