Adaptation of the human endocrine system to microgravity in the context of integrative physiology and ageing

This review deals with changes occurring in space in different endocrine systems. Sections are dedicated to hormones involved in bone remodelling, the hypothalamic-pituitary-adrenal axis, the hypothalamic-pituitary-thyroid axis, pancreatic hormones, the hypothalamic-pituitary-gonadal axis and the hypothalamic-pituitary-somato-mammotropic system. In space, most systems - especially those regulating bone/muscle metabolism and reproduction - undergo changes resembling those observed during senescence, but recover within weeks or months after return. This suggests space as a possible experimental model for the study of "reversible ageing processes". Studying ageing through space technology might give us the opportunity to combine the holistic view of integrative physiology with the most ambitious goal of the present scientific community, i.e. to yield successful ageing by promoting chronic disease prevention studies and by optimizing safe, anti-ageing therapeutic protocols.