The role of the gut microbiota and its metabolites: a new predictor in diabetes and its complications.

Type 2 diabetes (T2D) is easy to trigger many organ or system lesions, which can lead to various metabolic diseases, such as diabetic kidney disease (DKD), diabetic liver disease, diabetic cardiovascular disease, diabetic foot, etc. Due to the easy availability of stool and blood samples from patients, the study of gut microbes and their metabolites are progressing rapidly. The relationship between pathophysiological alterations of metabolic disorders and gut microbiota composition provides new approaches to precisely identify disease dynamics and refine disease treatment strategies. The aim of this review is to investigate the association between T2D with its complications and gut microbiota. Gut microbial metabolites are a new class of signaling molecules, and the mechanisms and pathways of their signal transduction have also been extensively studied. As a result, we will focus on the characteristics of gut microbiota and its metabolites in metabolic diseases as well as the relationship between gut barrier theory and the circulation of gut microbiota-derived metabolites in vivo. In addition, we elucidate the potential applicability of these characterizations and molecular mechanisms in clinical and pharmacological environment, analyzing their feasibility as predictive molecules for health management and clinically accurate predictions in daily life.