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 determined an increased prevalence of NAFLD (non-alcoholic fatty liver disease), making it the most common chronic liver disease in the Western world and a leading cause of liver transplantation. In the last few years, a rising number of studies conducted both on animal and human models have shown the existence of a close association between insulin resistance (IR), dysbiosis, and steatosis. However, all the mechanisms that lead to impaired permeability, inflammation, and fibrosis have not been fully clarified. Recently, new possible treatment modalities 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 (polyphenols 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 NAFLD 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 therapeutic strategies currently in use.

The importance of vitamin D and omega-3 PUFA supplementation: a nonpharmacologic immunomodulation strategy to halt autoimmunity.

The large, randomized, double-blind, placebo-controlled trial VITAL (Vitamin D and omega 3 trial) recently confirmed that vitamin D and omega-3 polyunsaturated fatty acid (PUFA) co-supplementation (VIDOM) can reduce the incidence of autoimmune diseases. Based on these relevant results, this commentary summarizes the molecular mechanisms behind the anti-inflammatory and immunomodulatory properties of vitamin D and omega-3 PUFAs. We also describe the potential bidirectional interplay between vitamin D metabolism and omega-3 PUFA metabolism that underlies the rationale for VIDOM co-supplementation and that may contribute to enhance the anti-inflammatory and immunomodulatory actions of vitamin D and omega-3 PUFAs when these compounds are administered in combination.

PUFA for human health: diet or supplementation?

Large doses of omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are used to treat several diseases including hypertriglyceridemia in humans. Modest levels of EPA and DHA may be obtained from food, particularly from fatty fish. This review presents the literature examining the differences between omega-3 fatty acid dietary supplementation and prescribed omega-3-acid ethyl esters (P-OM3). Reports published between 1995 and 2007 containing sources, recommended intake, and differences in the various formulations of omega-3 fatty acids were sought in PubMed and the Food and Drug Administration (FDA) Websites. However, lack of head-to-head clinical trials using both P-OM3 and dietary-supplement omega-3 fatty acids is the greatest limitation of this review. Although many kinds of omega-3 fatty acid dietary supplements are available, the efficacy, quality, and safety of these products are questionable because they are beyond any pharmaceutical control. Thus, P-OM3 is the only FDA approved omega-3 fatty acid product which is available in the United States as an adjunct to diet to improve human health.