Fecal microbiota transplantation in the metabolic diseases: Current status and perspectives

With the development of microbiology and metabolomics, the relationship between the intestinal microbiome and intestinal diseases has been revealed. Fecal microbiota transplantation (FMT), as a new treatment method, can affect the course of many chronic diseases such as metabolic syndrome, malignant tumor, autoimmune disease and nervous system disease. Although the mechanism of action of FMT is now well understood, there is some controversy in metabolic diseases, so its clinical application may be limited. Microflora transplantation is recommended by clinical medical guidelines and consensus for the treatment of recurrent or refractory Clostridium difficile infection, and has been gradually promoted for the treatment of other intestinal and extraintestinal diseases. However, the initial results are varied, suggesting that the heterogeneity of the donor stools may affect the efficacy of FMT. The success of FMT depends on the microbial diversity and composition of donor feces. Therefore, clinical trials may fail due to the selection of ineffective donors, and not to faulty indication selection for FMT. A new understanding is that FMT not only improves insulin sensitivity, but may also alter the natural course of type 1 diabetes by modulating autoimmunity. In this review, we focus on the main mechanisms and deficiencies of FMT, and explore the optimal design of FMT research, especially in the field of cardiometabolic diseases.