Study proves that gut immune system is closely related to nutrition

The gut is the largest cellular ecosystem that helps the body obtain nutrients from the environment

It's fine for carnivores and herbivores, whose digestive systems are organized differently and have adapted to their special diets; but for omnivores with the most complex systems, how does the complex work of the small intestine work?

In a recent study published in Science, a research team led by Yale University and the Howard Hughes Medical Institute (HHMI) illustrates the central role of the gut immune system in these critical processes: not only to defend against pathogens, but also regulate the intake of nutrients

The task of balancing nutrient absorption and host defense function in the small intestine is extraordinarily difficult for omnivores because diets change on a daily, seasonal and developmental time scale

In this study, researchers investigated how enzymes and transporters involved in macronutrient digestion and absorption are regulated with diet

Previous studies on intestinal defense against parasites and microbial pathogens have shown that interactions between intestinal epithelial cells and lymphocytes coordinate tissue responses to intestinal infections

The researchers found that mice fed a high-carbohydrate diet showed changes in the frequency of specific intestinal epithelial cell subsets

The researchers also discovered that a specific immune system signaling molecule called interleukin-22 (IL-22) plays a key role in fighting bacterial pathogens, such as those that cause food poisoning

In a series of experiments, the researchers found that γδ T cells suppressed IL-22 expression in mice and caused epithelial cells to activate digestive enzymes and nutrient transporters

This new study demonstrates the role of gut lymphocytes in regulating tissue responses to dietary nutrients and shows that lymphocyte-epithelial circuits and epithelial remodeling represent general features of gut adaptation to environmental changes

In addition, since bacterial infection leads to the expression of IL-22 and inhibits nutrient absorption, the findings also provide new insights into undernutrition in some underdeveloped populations, as well as for developing strategies to combat high-risk metabolic diseases such as obesity and diabetes.

(Source: China Biotechnology Network)

"China Food News" (03 edition on March 24, 2021)

(Editor-in-charge: Zhou Yan)