Novel therapeutic approaches based on the pathological role of gut dysbiosis on the link between nonalcoholic fatty liver disease and insulin resistance

The growing global epidemic of obesity and type 2 diabetes mellitus has de-termined an increased prevalence of NAFLD (non-alcoholic fatty liver disease), making it the most common chronic liver disease in the West-ern world and a leading cause of liver transplan-tation. In the last few years, a rising number of studies conducted both on animal and human models have shown the existence of a close as-sociation between insulin resistance (IR), dys-biosis, and steatosis. However, all the mecha-nisms that lead to impaired permeability, inflam- mation, and fibrosis have not been fully clari- fied. Recently, new possible treatment modali- ties have received much attention. To reach the review purpose, a broad-ranging literature search on multidisciplinary research databases was performed using the following terms alone or in combination: "NAFLD", "gut dysbiosis", "insulin resistance", "inflammation", "probiotics", "Chinese herbs". The use of probiotics, prebiotics, symbiotics, postbiotics, fecal microbiota transplant (FMT), Chinese herbal medicine, antibiotics, diet (poly -phenols and fasting diets), and minor therapies such as carbon nanoparticles, the MCJ protein, water rich in molecular hydrogen, seems to be able to improve the phenotypic pattern in NA-FLD patients. In this review, we provide an overview of how IR and dysbiosis contribute to the development and progression of NAFLD, as well as the thera-peutic strategies currently in use.