17β-estradiol Represses White Adipose Tissue Metabolism by Inhibiting PPARγ in High Fat Diet-induced Obese Female Ovariectomized Mice

This study investigated whether increased adiposity is prevented by estrogen replacement in female ovariectomized (OVX) C57BL/6J mice, an animal model of human menopause and whether these metabolic changes reflect the inhibitory action of estrogen on peroxisome proliferator-activated receptor γ (PPARγ)-regulated gene expression. Treatment of 17β-estradiol for the last one week of the experiment decreased high fat diet-induced body weight gain and white adipose tissue mass compared to OVX control mice. Histological analysis showed that administration of 17β-estradiol to mice decreased the size of adipocytes in parametrial adipose tissue versus OVX control mice. In addition, 17β-estradiol reduced the adipose expression of PPARγ as well as PPARγ target genes such as adipocyte fatty acid binding protein and tumor necrosis factor α. These results suggest that 17β-estradiol may inhibit adiposity through reducing the PPARγ activities in female OVX mice.