Environmental Impact on the Hypothalamus–Pituitary–Adrenal Axis

Abstract

Endocrine-disrupting chemicals (EDC) are exogenous compounds interfering with the actions of hormones at several steps. They are part of our environment and come in contact with humans frequently, through different routes. EDCs have shown deleterious effects on the endocrine system, mainly on the thyroid gland and steroid hormones, in the context of female and male reproduction. The hypothalamic–pituitary–adrenal (HPA) axis plays a pivotal role in the regulation of homeostasis, through regulation of adaptation to stress at multiple levels. Alterations of the HPA axis lead to severe metabolic and cardiovascular diseases, making this complex system a central player for human health. The HPA axis is a potential preferential target for disruption due to the chemical properties of EDCs and the specific features of the adrenal glands. Nonetheless, the consequences of EDCs exposure on the HPA axis have been underinvestigated to date in humans. The first part of this chapter provides an extensive summary of the mechanisms of HPA axis adaptation to environmental stimuli. The second part describes the current evidence on the deleterious effects of the main EDCs on the HPA axis.