Double-side role of short chain fatty acids on host health via the gut-organ axes

Short chain fatty acids (SCFA) exist in dietary foods and are produced by the fermentation of gut microbiota and are considered an important element for regulating host health. Through blood circulation, SCFA produced in the gut and obtained from foods have an impact on the intestinal health as well as vital organs of the host. It has been recognized that gut is the "vital organ" in the host, as the gut microbial metabolites, and SCFA could create an "axis" connecting the gut and to other organs. Therefore, the "gut-organ axes" have become a focus of research in recent years to analyze organism health. In this review, we summarized the sources and absorption properties, as well as the function of SCFA in both gut and other peripheral tissues (brain, kidney, liver, lung, bone and cardiovascular) in the way of "gut-organ axes". Short chain fatty acids exert both the beneficial and pathological role in gut and other organs in various ways, in which the beneficial effects are more pronounced. In addition, the beneficial effects are reflected in their both preventive and therapeutic effects. More importantly, the mechanisms behinds the gut and other tissues provided insight into the function of SCFA, assisting in the development of novel preventive and therapeutic strategies for maintaining the host health.