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- Schneider, K. M., et al.
(författare)
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Gut microbiota depletion exacerbates cholestatic liver injury via loss of FXR signalling
- 2021
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Ingår i: Nature Metabolism. - : Springer Science and Business Media LLC. - 2522-5812. ; 3:9, s. 1228-1241
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Tidskriftsartikel (refereegranskat)abstract
- Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown aetiology for which there are no approved therapeutic options. Patients with PSC display changes in gut microbiota and in bile acid (BA) composition; however, the contribution of these alterations to disease pathogenesis remains controversial. Here we identify a role for microbiota-dependent changes in BA synthesis that modulates PSC pathophysiology. In a genetic mouse model of PSC, we show that loss of microbiota-mediated negative feedback control of BA synthesis results in increased hepatic BA concentrations, disruption of bile duct barrier function and, consequently, fatal liver injury. We further show that these changes are dependent on decreased BA signalling to the farnesoid X receptor, which modulates the activity of the rate-limiting enzyme in BA synthesis, CYP7A1. Moreover, patients with advanced stages of PSC show suppressed BA synthesis as measured by serum C4 levels, which is associated with poor disease prognosis. Our preclinical data highlight the microbiota-dependent dynamics of BA metabolism in cholestatic liver disease, which could be important for future therapies targeting BA and gut microbiome interactions, and identify C4 as a potential biomarker to functionally stratify patients with PSC and predict disease outcomes. Patients with primary sclerosing cholangitis (PSC), a chronic cholestatic liver disease, display changes in the gut microbiota and in bile acid composition. Schneider, Candels and colleagues identify a role for microbiota-dependent regulation of bile acid synthesis through farnesoid X receptor signalling, which is relevant for PSC disease progression.
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| 2. |
- Su, H., et al.
(författare)
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Long-term hypercaloric diet exacerbates metabolic liver disease in PNPLA3 I148M animals
- 2023
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Ingår i: Liver International. - 1478-3223. ; 43:8, s. 1699-1713
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Tidskriftsartikel (refereegranskat)abstract
- Background & AimsNonalcoholic fatty liver disease (NAFLD) is a major health burden associated with the metabolic syndrome leading to liver fibrosis, cirrhosis and ultimately liver cancer. In humans, the PNPLA3 I148M polymorphism of the phospholipase patatin-like phospholipid domain containing protein 3 (PNPLA3) has a well-documented impact on metabolic liver disease. In this study, we used a mouse model mimicking the human PNPLA3 I148M polymorphism in a long-term high fat diet (HFD) experiment to better define its role for NAFLD progression. MethodsMale mice bearing wild-type Pnpla3 (Pnpla3(WT)), or the human polymorphism PNPLA3 I148M (Pnpla3(148M/M)) were subjected to HFD feeding for 24 and 52 weeks. Further analysis concerning basic phenotype, inflammation, proliferation and cell death, fibrosis and microbiota were performed in each time point. ResultsAfter 52 weeks HFD Pnpla3(148M/M) animals had more liver fibrosis, enhanced numbers of inflammatory cells as well as increased Kupffer cell activity. Increased hepatocyte cell turnover and ductular proliferation were evident in HFD Pnpla3(148M/M) livers. Microbiome diversity was decreased after HFD feeding, changes were influenced by HFD feeding (36%) and the PNPLA3 I148M genotype (12%). Pnpla3(148M/M) mice had more faecal bile acids. RNA-sequencing of liver tissue defined an HFD-associated signature, and a Pnpla3(148M/M) specific pattern, which suggests Kupffer cell and monocytes-derived macrophages as significant drivers of liver disease progression in Pnpla3(148M/M) animals. ConclusionWith long-term HFD feeding, mice with the PNPLA3 I148M genotype show exacerbated NAFLD. This finding is linked to PNPLA3 I148M-specific changes in microbiota composition and liver gene expression showing a stronger inflammatory response leading to enhanced liver fibrosis progression.
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