Gut microbiota as a candidate for lifespan extension:an ecological/evolutionary perspective targeted on livingorganisms as metaorganisms

An emerging central concept in evolutionarybiology suggests that symbiosis is a universalcharacteristic of living organisms that can help inunderstanding complex traits and phenotypes. Duringevolution, an integrative circuitry fundamental forsurvival has been established between commensal gutmicrobiota and host. On the basis of recent knowledgein worms, flies, and humans, an important roleof the gut microbiota in aging and longevity isemerging. The complex bacterial community thatpopulates the gut and that represents an evolutionaryadapted ecosystem correlated with nutrition appearsto limit the accumulation of pathobionts and infectionsin all taxa, being able of affecting the efficiencyof the host immune system and exerting systemicmetabolic effects. There is an urgent need todisentangle the underpinning molecular mechanisms,which could shed light on the basic mechanisms ofaging in an ecological perspective. Thus, it appearspossible to extend healthy aging and lifespan bytargeting the host as a metaorganism by manipulatingthe complex symbiotic ecosystem of gut microbiota,as well as other possible ecosystems of the body.