Combined Buckwheat D-Fagomine and Fish Omega-3 PUFAs Stabilize the Populations of Gut Prevotella and Bacteroides While Reducing Weight Gain in Rats

Some functional food components may help maintain homeostasis by promoting balanced gut microbiota. Here, we explore the possible complementary effects of D-fagomine and omega-3 polyunsaturated fatty acids (omega-3 PUFAs) eicosapentaenoic acid/docosahexaenoic acid (EPA/DHA 1:1) on putatively beneficial gut bacterial strains. Male Sprague-Dawley rats were supplemented with D-fagomine, omega-3 PUFAs, or both, for 23 weeks. Bacterial subgroups were evaluated in fecal DNA by quantitative real-time polymerase chain reaction (qRT-PCR) and short-chain fatty acids were determined by gas chromatography. We found that the populations of the genus Prevotella remained stable over time in animals supplemented with D-fagomine, independently of omega-3 PUFA supplementation. Animals in these groups gained less weight than controls and rats given only omega-3 PUFAs. D-Fagomine supplementation together with omega-3 PUFAs maintained the relative populations of Bacteroides. omega-3 PUFAs alone or combined with D-fagomine reduced the amount of acetic acid and total short-chain fatty acids in feces. The plasma levels of pro-inflammatory arachidonic acid derived metabolites, triglycerides and cholesterol were lower in both groups supplemented with omega-3 PUFAs. The D-fagomine and omega-3 PUFAs combination provided the functional benefits of each supplement. Notably, it helped stabilize populations of Prevotella in the rat intestinal tract while reducing weight gain and providing the anti-inflammatory and cardiovascular benefits of omega-3 PUFAs.