Gut-Kidney-Heart: A Novel Trilogy

Abstract

The microbiota represents a key factor in determining health and disease. Its role in inflammation and immunological disorders is well known, but it is also involved in several complex conditions, ranging from neurological to psychiatric, from gastrointestinal to cardiovascular diseases. It has recently been hypothesized that the gut microbiota may act as an intermediary in the close interaction between kidneys and the cardiovascular system, leading to the conceptualization of the "gut-kidney-heart" axis. In this narrative review, we will discuss the impact of the gut microbiota on each system while also reviewing the available data regarding the axis itself. We will also describe the role of gut metabolites in this complex interplay, as well as potential therapeutical perspectives.

Keywords: dysbiosis; gut microbiota; gut–kidney–heart axis; immune system; toxins.

Figure 1

The gut–kidney–heart trilogy. The gut microbiota influences human health by modulating organ function. Disequilibrium in the gut microbiota composition, called dysbiosis, leads to a “leaky gut”, resulting in systemic bacterial translocation with consequent activation of pro-inflammatory immune pathways. Moreover, in kidney disorders, gut permeability increases, while different renal toxins promote the multiplication of gut pathogenic bacteria. The relationship between the gut and the kidneys also involves the cardiovascular system, which has a bidirectional interaction with GM. In this figure, the main pathophysiological mechanisms and external factors that can modulate the gut microbiome, and vice versa, are presented.