PPARγ activity in subcutaneous abdominal fat tissue and fat mass gain during short-term overfeeding

Abstract

As the peroxisome proliferator-activated receptor γ (PPARγ) plays a central role in fat mass regulation, we investigated whether initial subcutaneous PPARγ activity is related to fat mass generation during overfeeding. Fourteen healthy female subjects (age 25±4 years, BMI 22.1±2.3 kg/m²). Subjects were overfed with a diet supplying 50% more energy than baseline energy requirements for 14 days. Fasting blood samples were analyzed for leptin, insulin and glucose. Fasting subcutaneous abdominal fat biopsies were obtained for analysis of PPARγ1, PPARγ2, aP2 and UCP2 mRNAs. Initial PPARγ1 and 2, aP2 and UCP2 mRNAs were not related to fat gain (P>0.12). However, PPARγ1, PPARγ2 and aP2 mRNA changes were positively related to changes in plasma leptin (PPγ and aP2 mRNA changes were positively related (Pγ mRNA levels reflected PPARγ activity. These data suggest that the ability to increase PPARγ activity might be involved in the susceptibility to gain weight during a positive energy balance.