MICROBIOTA AT THE CROSS ROAD OF DIET AND HEALTH: HOW DIETARY FATS SHAPE BACTERIAL LAND-SCAPE AND INFLUENCE GLOBAL HEALTH

Host-gut microbiota (GM) interactions play a pivotal role in shaping the delicate balance between health and disease within the human body. The impact of dietary factors, specifically high fat content diets on GM composition has been widely demonstrated. We have previously shown that the constant and sustained administration of Omega-3 fatty acids induced specific changes in GM composition, modulating the immune metabolic response of visceral adipose tissue (VAT) in our mouse model of obesity. We now set out to determine if this effect is Omega-3 dose-dependent. To achieve this, C57BL/6J(B6) mice were fed for 24 weeks with three diets, two with medium content total fat, but different Omega-3 content and a control diet. GM composition, metabolic biomarkers and immune cells in VAT were analyzed. A distinctive segregation of GM composition, a significantly higher proportion of regulatory T cells (CD45+CD4+FoxP3+), Omega-3 dose dependent and increased levels of leptin and cholesterol with no differences in adiponectin values were found in fat fed groups. Simple mediation analyses revealed significant associations between the microbial profile and immunometabolic regulation. To remark is the capacity of Lachnospiraceae UCG- 001 to modulate levels of leptin, glucose, and cholesterol through the stimulation of CD45+CD4+FOXP3+IL10+ cells. Our findings suggest a modulatory effect of omega-3 fatty acids on the microbiota, the metabolism, and the immunoregulatory capacity of VAT, supporting the hypothesis that alteration of the GM composition by omega-3 fatty acids may be a promising approach in managing obesity and associated metabolic diseases.