ROCHESTER, N.Y., July 8 (UPI) -- The vitamin D receptor is a key player in how "gut flora" maintain the digestive system, U.S. researchers said.
Researchers at the University of Rochester Medical Center in New York say the finding may provide a new lead in understanding how microbes in the human digestive tract known as gut flora keep bad bacteria in check.
"Our work suggests one possible mechanism, by working through the vitamin D receptor -- a molecule that binds with vitamin D and controls a number of functions -- a sensor and regulator for the majority of functions of vitamin D," study leader Jun Sun said in a statement.
Sun and colleagues looked at the role of the vitamin D receptor in the colons of normal mice, of mice in which the vitamin D receptor had been knocked out and of mice completely free of germs. They were exposed to a harmless strain of E. coli and to a pathogenic strain of Salmonella.
The researchers found the Salmonella much more virulent and aggressive in the mice with no vitamin D receptors. These mice showed higher inflammatory molecules activity levels, lost weight more quickly and were more likely to die in response to infection.
The study, published in the American Journal of Pathology, suggested the vitamin D receptor is key to fighting off an invading bacteria such as Salmonella by binding the inflammatory molecule NF-Kappa B and keeping it from activating other inflammatory molecules.
