Researchers at Emory University recently published findings on a class of chemicals known as indoles, which are produced by intestinal bacteria. These chemicals were shown to maintain the mobility and resilience of organisms such as worms, flies and mice during aging.
According to the authors, many studies have identified mechanisms and molecules to extend the lifespan of diverse organisms. However, lifespan does not equal healthspan—which they define as the proportion of time an organism remains healthy. The researchers sought to uncouple the two; indeed, they found that indoles from commensal microbiota extended the healthspan of diverse organisms but had a negligible effect on lifespan.
Further, these effects on healthspan were connected with the aryl hydrocarbon receptor (AHR), which has also been shown to act as an indicator for pollution-induced aging in skin, as shown by human epidermal keratinocytes.
In the Emory study, indoles from Caenorhabditis elegans, or round worm, showed a gene expression profile in aging animals reminiscent of younger animals—although distinct from normal aging. Moreover, in older animals, indole-induced genes extended fertility and reproductive span.
The authors concluded that the data suggests that indole acts to promote healthy aging. It also raises the possibility of developing therapies based on microbe-derived indole or its derivatives to extend the healthspan, and reduce frailty, in humans.
While implications from this work for anti-aging cosmetics or treatments were not specified, biological insights from aging have previously yielded insights to propel product development forward. Perhaps this research will, too. If nothing else, it highlights a new ideology with implications for how the industry could shift the conversation from "anti-aging" to healthy aging.