LOS ANGELES — In findings published in the March 1 issue of the Journal of Immunology, UCLA researchers investigating the role of nutrients in helping the immune system fight against major infections show that vitamin A may play an important role in combating tuberculosis.
The UCLA team describes for the first time the mechanism by which vitamin A and a specific gene assist the immune system by reducing the level of cholesterol in cells infected with TB. This is important because cholesterol can be used by TB bacteria for nutrition and other needs, the researchers said.
"If we can reduce the amount of cholesterol in a cell infected with tuberculosis, we may be able to aid the immune system in better responding to the infection," said senior author Philip Liu, an assistant professor of medicine in the divisions of dermatology and orthopedic surgery at UCLA's David Geffen School of Medicine and Orthopaedic Hospital Research Center. "Understanding how nutrients like vitamin A are utilized by our immune system to fight infections may provide new treatment approaches."
Although vitamin A circulates in the body in an inactive form known as retinol, it's the active form of the nutrient — all-trans reinoic acid — that is responsible for activating the immune system.
The UCLA team noted that this is an early study and that more research needs to be done before recommending vitamin A supplementation to combat tuberculosis or other infections.