Sex-dependent role of glucocorticoids and androgens in the pathophysiology of human obesity

Obesity, particularly its abdominal phenotype, a harbinger of the metabolic syndrome, cardiovascular diseases (CVDs) and type 2 diabetes mellitus (T2D), is becoming one of the most significant public health problems worldwide. Among many other potential factors, derangement of multiple hormone systems have increasingly been considered for their potential importance in the pathophysiology of obesity and the metabolic syndrome, with particular reference to glucocorticoids and sex hormones. These systems have a fundamental and coordinating role in the physiology of intermediate metabolism and cardiovascular function, and in the response to acute and chronic stress challenge. Abdominal obesity is associated with a hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis and impaired androgen balance, although these alterations differ according to sex. As there is also increasing evidence that there are many differences between the sexes in the susceptibility and development of obesity, T2D and CVDs, we support the hypothesis that alterations of the HPA axis and androgen balance may have an important function in this context. This is further supported by the fact that there are important differences between males and females in their ability to adapt to both internal and particularly to environmental (external) stressors. In addition, there is also evidence that, in both physiological and pathological conditions, a close cross talk exists between sex hormones and glucocorticoids at both neuroendocrine and peripheral level, again with different specificities according to sex.