IMPLICATION OF GUT MICROBIOTA IN DIABETES MELLITUS AND OBESITY

Differences in the composition of the species of microorganisms in the gut may predict the evolution toward obesity and diabetes mellitus. We carried out a systematic review of the studies dedicated to the role of gut microbiota in diabetes mellitus and obesity.

A systematic literature search of electronic databases was performed, using the search syntax: "Gut microbiota and diabetes and obesity"; abstracts in English, with data about mechanisms of pathogenesis and treatment options by changing the gut composition were included (259 articles). Studies were excluded if they did not have an abstract, or they contained no data about the exact implication mechanism of microbiota.

There are differences regarding the composition of the gut microbiota in healthy people and type 2 diabetes mellitus patients; the later proved to have significantly decreased Clostridium components, and increased Lactobacillus and Bifidobacterium populations.The intestines of obese subjects are less rich in microbial genes, have a reduced amount of Bacteroidetes and an increased amount of Firmicutes. Fecal microbiota transplantation from obese subjects resulted in adoption of the donor somatotype. Early differences in gut microbiota composition (higher number of Bifidobacteria) function as diagnostic markers for the development of type 2 diabetes mellitus in high-risk patients.The gut endotoxins contribute to metabolic syndrome manifestation. Experimental studies with prebiotic showed lower levels of cytokines and antiobesity potential.

Microbiota composition and its changes since childhood have an important role in the metabolic syndrome. Any intervention in order to prevent or treat obesity and diabetes mellitus should have as target the gut immune system.