ABSTRACT: Metabolic study of various Bile acids. Data was generated on a Thermo Q Exactive and C18 RP UHPLC. Positive polarity acquisition on LC-MS/MS.
Project description:Intestinal lipid absorption, the entry point for fats into the body, requires the coordinated actions of bile acids and lipases. Here, we uncover distinct yet cooperative roles of bile acids in driving the differential uptake of dietary fatty acids. We first decreased the bile acid pool size by disrupting the rate-limiting enzyme in bile acid synthesis, Cyp7a1, using liver-directed gene editing in mice. Compared with lipase inhibition, reduced bile acids prevented diet-induced obesity, increased anorectic hormones, suppressed excessive eating, and improved systemic lipid metabolism. Remarkably, decreasing bile acids selectively reduced the absorption of saturated fatty acids but preserved polyunsaturated fatty acids. By targeting additional bile acid enzymes, we identified specific functions of individual bile acid species. Mechanistically, we show that cholic acid preferentially solubilizes polyunsaturated fatty acids into mixed micelles for intestinal uptake. Our studies demonstrate that bile acids can selectively control fatty acid uptake, revealing insights for future interventions in metabolic diseases.
Project description:Chronic hepatitis B, C and D virus (HBV, HCV, HDV) infections are leading causes of liver disease and cancer worldwide. Although these viruses differ markedly in their life cycle and genomic organization, they exclusively infect hepatocytes. Recently, the sodium taurocholate cotransporting polypeptide (NTCP) was identified as the first functional receptor for HBV and HDV. Here, we report that NTCP also facilitates HCV entry into human hepatocytes, by augmenting the bile acids-mediated repression of IFN-stimulated genes (ISGs), including IFITM2 and IFITM3, to increase the susceptibility of cells to HCV entry. Furthermore, an HBV-derived preS1 peptide, known to bind NTCP and to inhibit bile acids uptake and HBV infection, inhibits HCV entry by enhancing the expression of ISGs. Our study highlights NTCP as a novel player linking bile acids metabolism to the interferon response in hepatocytes and establishes a role for NTCP in the entry process of multiple hepatotropic viruses, via distinct mechanisms. Collectively, these findings enhance our understanding of hepatitis virus-host interactions and suggest NTCP as an attractive antiviral target for HBV/HCV co-infection.
Project description:In this study, we aimed at the characterization of C. difficile’s stress response to the main four human bile acids. Although, a phenotypically description of growth differences upon challenge with different bile acids has been described (Lewis 2016, Thanissery 2017), there is no information on the adaptation of gene expression available. We employed a comprehensive proteomics approach to record stress signatures of the unconjugated bile acids CA, CDCA, DCA and LCA in shock experiments as well as during long-term-stress conditions and could depict a general stress response concerning all four bile acids, but also specific responses to only a single or a few of the different bile acids. Our results are a starting point for the understanding of how the individual bile acids cocktail of a patient can decide on the outcome of a C. difficile infection.
Project description:We propose certain bile acids bind to a highly conserved pocket in the glucocorticoid receptor ligand binding domain, interfere with receptor multimerization and modulate its transcriptional activity.
Project description:In this study, we aimed at the characterization of C. difficile’s stress response to the main four human bile acids. Although, a phenotypically description of growth differences upon challenge with different bile acids has been described (Lewis 2016, Thanissery 2017), there is no information on the adaptation of gene expression available. We employed a comprehensive proteomics approach to record stress signatures of the unconjugated bile acids CA, CDCA, DCA and LCA during long-term-stress conditions and could depict a general stress response concerning all four bile acids, but also specific responses to only a single or a few of the different bile acids. Our results are a starting point for the understanding of how the individual bile acids cocktail of a patient can decide on the outcome of a C. difficile infection
Project description:Metabolic study of various Standards. Data was generated on a Thermo Q Exactive and C18 RP UHPLC. Positive and Negative polarity acquisition on LC-MS/MS.