Mice caecal content Raw sequence reads

Because the gut microbiota contributes to metabolic health, it is important to determine specific diet-microbiota interactions that influence host metabolism. Bile acids and dietary fat type can alter phenotypes of diet-induced obesity, but the interplay with intestinal microorganisms is unclear. Here we investigated metabolic consequences of diets enriched in primary bile acids, lard, or palm oil in mice, and studied gut microbiota structure and functions.When combined with bile acids, dietary lard fed to mice for a period of 8 weeks triggered fat mass accumulation in colonized but not in germfree mice. This difference was associated with impaired glucose tolerance, lower fasting insulin levels, fatty liver, and elevated amounts of hepatic triglycerides, cholesterol esters, and mono-unsaturated fatty acids. Lard-fed mice were characterized by decreased relative abundances of Lachnospiraceae and by increased occurrence of Desulfovibrionaceae and the species Clostridium lactatifermentaens and Flintibacter butyricus. Metatranscriptomics…Caution is required when interpreting data from diet-induced obesity models due to varying effects of dietary fat type. Detrimental metabolic consequences of lard in combination with bile acids in diet is dependent on microbial colonization of the host, is linked to hepatic lipid rearrangements and to changes in microbiota functions.