Mechanisms for sex differences in energy regulation
Males and females differ in the circulating levels of sex hormones, as well as the sex chromosome content of their cells. These factors are major contributors to sexual dimorphism in energy balance, and all sex hormones – oestrogens, progesterone and androgens – play sex-dependent roles in the regulation of body weight, as Wang et al. examine in this review.
Androgens have a prominent role in the regulation of body weight and energy balance in both sexes. In women, higher serum androgen concentrations correlate with a higher body mass index, while in men serum testosterone levels are inversely correlated with obesity. In female mice, chronic treatment with dihydrotestosterone increases adiposity. Male mice with global androgen receptor knockout show an age-dependent phenotype, with increased body weight and adiposity in aged males. Androgen signalling in the liver also contributes to energy homeostasis, as male mice lacking liver androgen receptors develop obesity when fed with a high fat diet, while female mice do not.
Factors other than sex hormones or their receptors are also likely to contribute to the sex-dependent differences in regulation of body weight. The authors suggest these factors should form a focus for future studies.
Read the full article in Journal of Molecular Endocrinology 62 R129–R143