On the environmental stress that reshapes our vessels

This editorial refers to ‘Pregnane X receptor regulates drug metabolism and transport in the vasculature and protects from oxidative stress’ by K.E. Swales et al. , pp. 674–681, this issue. Adaptation to environmental stress is key to animal survival. Humans, however, are temporarily above some of the consequences of the environmental stress by the use of vaccines, antibiotics, and organ transplantation; they are, however, not totally immune to their environment. The fundamental questions are (i) how do we detect the environmental stress and (ii) how do we adapt to it?Stress comes in a multitude of flavours. The classical risk factors for cardiovascular diseases are by definition deleterious, but the vessels certainly tentatively adapt to them.1 An intermittent low level of ischaemia generated by exercise2 and during ischaemic preconditioning3 is another type of stress that activates defence and repair pathways and that is beneficial to the cardiovascular system. While our lifestyle shapes our metabolism and overall biology, most cell types express receptors that sense chemicals, natural or not, contained in what we ingest and what we breathe. The ensuing signals modify the cells, making certain that they are able to appropriately use these chemicals as well as to resist to their toxicity if needed. Overall, these responses, also known as hormetic responses, are mid- …