Key points from article :
Researchers grew C. elegans nematodes in petri dishes with and without bacteria, which is what they eat.
Some plates had a thin layer of bacteria on the lid, so the nematodes could smell them but couldn’t eat them.
Smell of bacteria offset some of the lifespan extension caused by dietary restriction.
Carried out experiments using loss-of-function mutants, neuron activity measurements, and cell-specific depletion or overexpression of genes, to piece together the neural circuit involved.
Olfactory circuit signals the gut to suppress DR-mediated longevity via octopamine, the mammalian homolog of norepinephrine.
Octopamine affects lifespan by regulating the energy sensor AMPK in the intestine.
Cultures of mouse cells also showed that norepinephrine activates AMPK via the same signaling pathway.
The idea that lifespan could be extended by manipulating the perception of food is certainly appealing.
Research by University of Michigan published in Nature Aging.