Project description:Microbial RNAseq analysis of cecal and fecal samples collected from mice colonized with the microbiota of human twins discordant for obesity. Samples were colleted at the time of sacrifice, or 15 days after colonization from mice gavaged with uncultured or cultured fecal microbiota from the lean twins or their obese co-twins. Samples were sequenced using Illumina HiSeq technology, with 101 paired end chemistry. Comparisson of microbial gene expression between the microbiota of lean and obese twins fed a Low fat, rich in plant polysaccharide diet.
Project description:Aconitate decarboxylase 1 (ACOD1) is the enzyme synthesizing itaconate, an immuno-regulatory metabolite tuning host-pathogen interactions. Such functions are achieved by affecting metabolic pathways regulating inflammation and microbe survival. However, at the whole-body level, metabolic roles of itaconate remain largely unresolved. By using multiomics-integrated approaches, here we show that ACOD1 responds to high-fat diet consumption in mice by promoting gut microbiota alterations supporting metabolic disease. Genetic disruption of itaconate biosynthesis protects mice against obesity, alterations in glucose homeostasis and liver metabolic dysfunctions by decreasing meta-inflammatory responses to dietary lipid overload. Mechanistically, fecal metagenomics and microbiota transplantation experiments demonstrate such effects are dependent on an amelioration of the intestinal ecosystem composition, skewed by high-fat diet feeding towards obesogenic phenotype. In particular, unbiased fecal microbiota profiling and axenic culture experiments point towards a primary role for itaconate in inhibiting growth of Bacteroidaceae and Bacteroides, family and genus of Bacteroidetes phylum, the major gut microbial taxon associated with metabolic health. Specularly to the effects imposed by Acod1 deficiency on fecal microbiota, oral itaconate consumption enhances diet-induced gut dysbiosis and associated obesogenic responses in mice. Unveiling an unrecognized role of itaconate, either endogenously produced or exogenously administered, in supporting microbiota alterations underlying diet-induced obesity in mice, our study points ACOD1 as a target against inflammatory consequences of overnutrition.
Project description:5 human fecal gut samples, collected and prepared for standard MudPIT data collection from healthy volunteers, searched with the ComPIL database. x3 replicates each