Gut-bacteria metabolite linked to lower diabetes risk

Last Updated: 2017-04-20

By David Douglas

NEW YORK (Reuters Health) - Higher serum levels of indolepropionic acid, a gut microbiota-produced metabolite, are associated with reduced risk of type 2 diabetes, a new study shows.

"Our finding further underlines the importance of the colonic microbiota on our health, however a direct identification of intestinal bacteria is a complex process, which is why identifying the metabolites produced by intestinal bacteria may be a more feasible method for evaluating the role of intestinal bacteria in the pathogenesis of diabetes, as well as other lifestyle-related chronic diseases,” Drs. Kati Hanhineva and Matti Uusitupa of the University of Eastern Finland, in Kuopio, explained in a joint email to Reuters Health.

The two researchers and their colleagues examined the serum metabolite profile of 200 participants in a diabetes-prevention study. All had impaired glucose tolerance.

Over the course of a 15-year follow-up, 96 developed diabetes and 104 did not, the team notes in Scientific Reports, online April 11. Several novel metabolites were associated with a lower diabetes risk, including indole and lipid-related metabolites.

There was an inverse association of indolepropionic acid with diabetes risk. This finding was validated in two independent dietary studies, one of which had 503 incident diabetes cases and matched healthy controls and another in which 55 of 110 originally healthy participants developed diabetes over a five-year follow-up.

The researchers observe that a diet rich in whole grain products and dietary fiber increased the indolepropionic acid concentration and that overall, the majority of the lipids were negatively correlated with the intake of saturated fatty acids. In animal models, such lipids have been reported to induce insulin secretion from pancreatic beta cells.

The protective effect of these metabolites, they add, might be at least partly due to their influence on insulin secretion and perhaps low-grade inflammation.

"These novel metabolites," Dr. Hanhineva pointed out, "may help to monitor health effects of certain dietary components, e.g. dietary fiber and prebiotics and (novel) probiotics with regard to prevention and lifestyle therapy of chronic diseases, in particular type 2 diabetes."

The results, she concluded, "may also give some hints to development of new drugs for the treatment of type 2 diabetes. This is particularly true with indolepropionic acid that may have direct or indirect effects via gut hormones on beta-cell function and insulin secretion."

SOURCE: http://bit.ly/2o7F1jJ

Sci Rep 2017.