Altering Gut Bacteria May Lengthen Lifespan
Altering gut bacteria may help promote longevity, according to a new study.
Researchers were able to promote health and increase lifespan in fruit flies by altering the symbiotic, or commensal, relationship between bacteria and the absorptive cells lining the intestine.
Researchers said that latest findings suggest that having the right balance of gut bacteria may be the secret to enjoying a long and healthy life.
"Our study explores age-related changes in the gut that include increased oxidative stress, inflammation, impaired efficiency of the immune response, and the over-proliferation of stem cells," lead author Heinrich Jasper said in a news release. "It puts these changes into a hierarchical, causal relationship and highlights the points where we can intervene to rescue the negative results of microbial imbalance."
Researchers explain that the bacterial load in fly intestines increases significantly with age, which can result in an inflammatory condition. The imbalance is then driven by chronic activation of the stress response gene FOXO, which suppresses the activity of a class of molecules (PGRP-SCs, homologues of PGLYRPs in humans) that immune imbalance increases bacterial numbers and triggers an inflammatory response that include the production of free radicals. Free radicals lead to over-proliferation of stem cells in the gut, resulting in epithelial dysplasia, a pre-cancerous state.
The study found that increasing the expression of PGRP-SC in epithelial cells of the gut restored the microbial balance and limited stem cell proliferation. Researchers said this boost in PGRP-SC function, which could be mimicked by drugs, successfully lengthened the lifespan of flies.
"If we can understand how aging affects our commensal population - first in the fly and then in humans - - our data suggest that we should be able to impact health span and life span quite strongly, because it is the management of the commensal population that is critical to the health of the organism," Jasper concluded.
The findings are published in the journal Cell.