Research progress in gut-lung axis and lung diseases

There is a huge amount of microbial community in the human intestinal tract, among which the gut microbiota accounts for the largest proportion, which is crucial for maintaining the normal physiological function of human body. Gut microbiota imbalance not only affects gastrointestinal function, but also damages organ functions outside the gastrointestinal tract. Recently, scholars have put forward the doctrines of the "gut-liver" axis and the "gut-brain" axis based on the interrelation and influence between the intestine and other organs. With the deepening of research, the role of gut microbiota in the development and progression of lung diseases has been increasingly concerned, and the theory of "gut-lung" axis has been gradually formed, which is also consistent with the theory described in traditional medicine as "The lung stands in interior-exterior relationship with the large intestine". This paper mainly introduces the research progress of the "gut-lung" axis and lung-related diseases for providing a re