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Research tells us that the “good” bacteria that inhabit our intestines help to regulate our metabolism. A new study in fruit flies shows one of the ways in which these commensal microbes keep us metabolically fit.
The findings, published today in Cell Metabolism, suggest that innate immune pathways, our first line of defense against bacterial infection, have a side job that’s equally important.
The intestine’s digestive cells use an innate immune pathway to respond to harmful bacteria by producing antimicrobial peptides. But other intestinal cells, enteroendocrine cells, use the same pathway, known as IMD, to respond to “good” bacteria — by fine-tuning body metabolism to diet and intestinal conditions.
“What’s most interesting to me is that some innate immune pathways aren’t just for innate immunity,” says Paula Watnick, MD, PhD, of the Division of Infectious Diseases at Boston Children’s Hospital. “Innate immune pathways are also listening to the ‘good’ bacteria – and responding metabolically.” …
