Long-lived dwarf mice: are bile acids a longevity signal?

Pathways that control aging act via regulated biochemical processes, among which metabolism of xenobiotics (potentially harmful chemical agents encountered as environmental toxicants, for example, drugs, or produced internally) is one possible candidate. A new study of long-lived Ghrhr mutant mice reports that increased bile acid levels activate xenobiotic metabolism via the nuclear receptor, farnesoid X receptor. This increases resistance to xenobiotic stress, possibly contributing to longevity.