The gut-liver axis: ways of maintaining the body’s homeostasis. Historical aspects and the current state of the problem. Literature review

There are close evolutionary anatomical and functional connections between the intestine and the liver. Whereas the peculiarities of functioning of these organs as components of the digestive system have long been the object of scientific research, their role in maintaining the body’s homeostasis has been studied relatively recently. This especially applies to the immune aspects of the interaction of these organs. The intestinal mucosa performs not only the function of a mechanical barrier, but also provides an immune response to pathogens while maintaining tolerance to one’s own flora, which together prevents the translocation of antigens into the internal environment of the body. In this aspect, the intestinal microbiocenosis is of particular interest, as it plays an important role in maintaining the integrity of the intestinal barrier and reducing bacterial translocation, forming and modulating the activity of the local immune system, and has a regulatory effect on the body’s metabolic processes. A decrease in the barrier function of the intestines leads to the contact of translocated antigens of bacterial origin and other xenobiotics with the structures of adaptive immunity, and through the portal blood flow with the lymphoid structures of the liver, triggers a cascade of inflammatory reactions, and as a result, to the development of pathological processes in the hepatobiliary zone and metabolic disorders. Understanding these processes contributes to the emergence of promising directions in the prevention and treatment of a wide range of pathological conditions, for example, violations of food tolerance, some allergic diseases. The review summarizes historical aspects and modern views on the role of the «intestine‑liver» axis in ensuring the metabolic and immune homeostasis of the body, as well as data on pathological conditions that develop when this axis is disturbed.