Effects of chronic testosterone administration on body weight and food intake differ among pre-pubertal, gonadal-intact, and ovariectomized female rats

Abstract

In females, estrogens play pivotal roles in preventing excessive body weight gain. On the other hand, the roles of androgen in female appetite and body weight regulation have not been fully studied. In this study, whether the roles of androgen in the regulation of body weight and appetite were different among ages and/or the estrogen milieu in females was evaluated. Body weight gain and food intake were increased by chronic testosterone administration in pre-pubertal and gonadal-intact female rats, but not in ovariectomized female rats. Testosterone administration also affected the serum leptin level and adipose leptin gene expression levels differently in each experimental condition. Hypothalamic mRNA levels of ERα, which plays pivotal roles in regulation of body weight and metabolism, were decreased by chronic testosterone administration in pre-pubertal and gonadal-intact female rats, but not in ovariectomized female rats. These results indicate that the effects of testosterone on body weight and appetite differed among ages and/or estrogen milieu in female rats, and that attenuation of estrogens’ actions on the hypothalamus might be partly involved in the androgen-induced increases of body weight gain and food intake in females.