Amanda Garrido1, Eunjeong Kim1, Ana Teijeiro1, Paula Sánchez Sánchez1, Rosa Gallo1, Ajay Nair2, María Matamala Montoya1, Cristian Perna3, Guillermo P Vicent4, Javier Muñoz5, Ramón Campos-Olivas6, Johannes C Melms7, Benjamin Izar7, Robert F Schwabe2, Nabil Djouder8. 1. Molecular Oncology Programme, Growth Factors, Nutrients and Cancer Group, Centro Nacional Investigaciones Oncológicas (CNIO), Madrid, 28029, Spain. 2. Department of Medicine, Columbia University, New York, NY 10032, USA. 3. Department of Pathology, Hospital Universitario Ramón y Cajal (IRYCIS), Madrid, 28034, Spain. 4. Molecular Biology Institute of Barcelona, Consejo Superior de Investigaciones Científicas (IBMB-CSIC), Barcelona, 08028, Spain. 5. Biotechnology Programme, Proteomics Core Unit, Centro Nacional Investigaciones Oncológicas (CNIO), Madrid, 28029, Spain; Present address: Biocruces Bizkaia Health Research Institute. Ikerbasque, Basque Foundation for Science, Bilbao, 48013, Spain. 6. Structural Biology Programme, Spectroscopyand Nuclear Magnetic Resonance Unit, Centro Nacional Investigaciones Oncológicas (CNIO), Madrid, 28029, Spain. 7. Department of Medicine, Division of Hematology and Oncology, Irving Medical Center, Columbia University, New York, NY 10032, USA. 8. Molecular Oncology Programme, Growth Factors, Nutrients and Cancer Group, Centro Nacional Investigaciones Oncológicas (CNIO), Madrid, 28029, Spain. Electronic address: ndjouder@cnio.es.
Abstract
BACKGROUND & AIMS: Owing to the lack of genetic animal models that adequately recreate key clinical characteristics of cirrhosis, the molecular pathogenesis of cirrhosis has been poorly characterized, and treatments remain limited. Hence, we aimed to better elucidate the pathological mechanisms of cirrhosis using a novel murine model. METHODS: We report on the first murine genetic model mimicking human cirrhosis induced by hepatocyte-specific elimination of microspherule protein 1 (MCRS1), a member of non-specific lethal (NSL) and INO80 chromatin-modifier complexes. Using this genetic tool with other mouse models, cell culture and human samples, combined with quantitative proteomics, single nuclei/cell RNA sequencing and chromatin immunoprecipitation assays, we investigated mechanisms of cirrhosis. RESULTS: MCRS1 loss in mouse hepatocytes modulates the expression of bile acid (BA) transporters - with a pronounced downregulation of Na+-taurocholate cotransporting polypeptide (NTCP) - concentrating BAs in sinusoids and thereby activating hepatic stellate cells (HSCs) via the farnesoid X receptor (FXR), which is predominantly expressed in human and mouse HSCs. Consistently, re-expression of NTCP in mice reduces cirrhosis, and genetic ablation of FXR in HSCs suppresses fibrotic marks in mice and in vitro cell culture. Mechanistically, deletion of a putative SANT domain from MCRS1 evicts histone deacetylase 1 from its histone H3 anchoring sites, increasing histone acetylation of BA transporter genes, modulating their expression and perturbing BA flow. Accordingly, human cirrhosis displays decreased nuclear MCRS1 and NTCP expression. CONCLUSIONS: Our data reveal a previously unrecognized function of MCRS1 as a critical histone acetylation regulator, maintaining gene expression and liver homeostasis. MCRS1 loss induces acetylation of BA transporter genes, perturbation of BA flow, and consequently, FXR activation in HSCs. This axis represents a central and universal signaling event in cirrhosis, which has significant implications for cirrhosis treatment. LAY SUMMARY: By genetic ablation of MCRS1 in mouse hepatocytes, we generate the first genetic mouse model of cirrhosis that recapitulates human features. Herein, we demonstrate that the activation of the bile acid/FXR axis in liver fibroblasts is key in cirrhosis development.
BACKGROUND & AIMS: Owing to the lack of genetic animal models that adequately recreate key clinical characteristics of cirrhosis, the molecular pathogenesis of cirrhosis has been poorly characterized, and treatments remain limited. Hence, we aimed to better elucidate the pathological mechanisms of cirrhosis using a novel murine model. METHODS: We report on the first murine genetic model mimicking human cirrhosis induced by hepatocyte-specific elimination of microspherule protein 1 (MCRS1), a member of non-specific lethal (NSL) and INO80 chromatin-modifier complexes. Using this genetic tool with other mouse models, cell culture and human samples, combined with quantitative proteomics, single nuclei/cell RNA sequencing and chromatin immunoprecipitation assays, we investigated mechanisms of cirrhosis. RESULTS: MCRS1 loss in mouse hepatocytes modulates the expression of bile acid (BA) transporters - with a pronounced downregulation of Na+-taurocholate cotransporting polypeptide (NTCP) - concentrating BAs in sinusoids and thereby activating hepatic stellate cells (HSCs) via the farnesoid X receptor (FXR), which is predominantly expressed in human and mouse HSCs. Consistently, re-expression of NTCP in mice reduces cirrhosis, and genetic ablation of FXR in HSCs suppresses fibrotic marks in mice and in vitro cell culture. Mechanistically, deletion of a putative SANT domain from MCRS1 evicts histone deacetylase 1 from its histone H3 anchoring sites, increasing histone acetylation of BA transporter genes, modulating their expression and perturbing BA flow. Accordingly, human cirrhosis displays decreased nuclear MCRS1 and NTCP expression. CONCLUSIONS: Our data reveal a previously unrecognized function of MCRS1 as a critical histone acetylation regulator, maintaining gene expression and liver homeostasis. MCRS1 loss induces acetylation of BA transporter genes, perturbation of BA flow, and consequently, FXR activation in HSCs. This axis represents a central and universal signaling event in cirrhosis, which has significant implications for cirrhosis treatment. LAY SUMMARY: By genetic ablation of MCRS1 in mouse hepatocytes, we generate the first genetic mouse model of cirrhosis that recapitulates human features. Herein, we demonstrate that the activation of the bile acid/FXR axis in liver fibroblasts is key in cirrhosis development.
Authors: Peter Fickert; Andrea Fuchsbichler; Tarek Moustafa; Martin Wagner; Gernot Zollner; Emina Halilbasic; Ulrike Stöger; Marco Arrese; Margarita Pizarro; Nancy Solís; Gonzalo Carrasco; Alessandra Caligiuri; Martina Sombetzki; Emil Reisinger; Oleksiy Tsybrovskyy; Kurt Zatloukal; Helmut Denk; Hartmut Jaeschke; Massimo Pinzani; Michael Trauner Journal: Am J Pathol Date: 2009-11-12 Impact factor: 4.307
Authors: Krishna S Tummala; Marta Brandt; Ana Teijeiro; Osvaldo Graña; Robert F Schwabe; Cristian Perna; Nabil Djouder Journal: Cell Rep Date: 2017-04-18 Impact factor: 9.423
Authors: Gideon M Hirschfield; Andrew Mason; Velimir Luketic; Keith Lindor; Stuart C Gordon; Marlyn Mayo; Kris V Kowdley; Catherine Vincent; Henry C Bodhenheimer; Albert Parés; Michael Trauner; Hanns-Ulrich Marschall; Luciano Adorini; Cathi Sciacca; Tessa Beecher-Jones; Erin Castelloe; Olaf Böhm; David Shapiro Journal: Gastroenterology Date: 2014-12-11 Impact factor: 22.682