Juan P Arab1, Daniel Cabrera2, Tejasav S Sehrawat3, Nidhi Jalan-Sakrikar3, Vikas K Verma3, Douglas Simonetto3, Sheng Cao3, Usman Yaqoob3, Jonathan Leon4, Mariela Freire4, Jose I Vargas4, Thiago M De Assuncao3, Jung H Kwon3, Yi Guo3, Enis Kostallari3, Qing Cai5, Tatiana Kisseleva6, Youngman Oh5, Marco Arrese4, Robert C Huebert3, Vijay H Shah7. 1. Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA; Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile. 2. Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile; Departamento de Ciencias Químicas y Biológicas, Universidad Bernardo O Higgins, Santiago, Chile. 3. Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA. 4. Departamento de Gastroenterologia, Escuela de Medicina, Pontificia Universidad Catolica de Chile, Santiago, Chile. 5. Department of Pathology, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, VA, USA. 6. Department of Surgery, University of California-San Diego, San Diego, CA, USA. 7. Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA. Electronic address: shah.vijay@mayo.edu.
Abstract
BACKGROUND & AIMS: Steatohepatitis drives fibrogenesis in alcohol-related liver disease. Recent studies have suggested that hepatic stellate cells (HSCs) may regulate the parenchymal cell injury and inflammation that precedes liver fibrosis, although the mechanism remains incompletely defined. Neuropilin-1 (NRP-1) and synectin are membrane proteins implicated in HSC activation. In this study, we disrupted NRP-1 and synectin as models to evaluate the role of HSC activation on the development of steatohepatitis in response to alcohol feeding in mice. METHODS: Mice with HSC-selective deletion of NRP (ColCre/Nrp1loxP) or synectin (ColCre/synectinloxP) vs. paired Nrp1loxP or synectinloxP mice were fed a control diet or the chronic/binge alcohol feeding model. Several markers of steatosis and inflammation were evaluated. RESULTS: ColCre/Nrp1loxP mice showed less fibrosis, as expected, but also less inflammation and steatosis, with lower hepatic triglyceride content. Similar results were observed in the synectin model. Hepatocytes treated with supernatant of HSCs from ColCre/Nrp1loxP mice compared to supernatant from Nrp1loxP mice were protected against ethanol-induced lipid droplet formation. An adipokine and inflammatory protein array from the supernatant of HSCs with NRP-1 knockdown showed a significant reduction in Igfbp3 (a major insulin-like growth factor-binding protein with multiple metabolic functions) and an increase in SerpinA12 (a serine-protease inhibitor) secretion compared to wild-type HSCs. Recombinant Igfbp3 induced lipid droplets, triglyceride accumulation, and lipogenic genes in hepatocytes in vitro, while SerpinA12 was protective against ethanol-induced steatosis. Finally, Igfbp3 was increased, and SerpinA12 was decreased in serum and liver tissue from patients with alcoholic hepatitis. CONCLUSION: Selective deletion of NRP-1 from HSCs attenuates alcohol-induced steatohepatitis through regulation of Igfbp3 and SerpinA12 signaling. LAY SUMMARY: Hepatic stellate cells are known for their role in fibrosis (scarring of the liver). In this study, we describe their role in the modulation of fat deposition and inflammation in the liver, which occurs secondary to alcohol damage.
BACKGROUND & AIMS:Steatohepatitis drives fibrogenesis in alcohol-related liver disease. Recent studies have suggested that hepatic stellate cells (HSCs) may regulate the parenchymal cell injury and inflammation that precedes liver fibrosis, although the mechanism remains incompletely defined. Neuropilin-1 (NRP-1) and synectin are membrane proteins implicated in HSC activation. In this study, we disrupted NRP-1 and synectin as models to evaluate the role of HSC activation on the development of steatohepatitis in response to alcohol feeding in mice. METHODS:Mice with HSC-selective deletion of NRP (ColCre/Nrp1loxP) or synectin (ColCre/synectinloxP) vs. paired Nrp1loxP or synectinloxP mice were fed a control diet or the chronic/binge alcohol feeding model. Several markers of steatosis and inflammation were evaluated. RESULTS: ColCre/Nrp1loxP mice showed less fibrosis, as expected, but also less inflammation and steatosis, with lower hepatic triglyceride content. Similar results were observed in the synectin model. Hepatocytes treated with supernatant of HSCs from ColCre/Nrp1loxP mice compared to supernatant from Nrp1loxP mice were protected against ethanol-induced lipid droplet formation. An adipokine and inflammatory protein array from the supernatant of HSCs with NRP-1 knockdown showed a significant reduction in Igfbp3 (a major insulin-like growth factor-binding protein with multiple metabolic functions) and an increase in SerpinA12 (a serine-protease inhibitor) secretion compared to wild-type HSCs. Recombinant Igfbp3 induced lipid droplets, triglyceride accumulation, and lipogenic genes in hepatocytes in vitro, while SerpinA12 was protective against ethanol-induced steatosis. Finally, Igfbp3 was increased, and SerpinA12 was decreased in serum and liver tissue from patients with alcoholic hepatitis. CONCLUSION: Selective deletion of NRP-1 from HSCs attenuates alcohol-induced steatohepatitis through regulation of Igfbp3 and SerpinA12 signaling. LAY SUMMARY: Hepatic stellate cells are known for their role in fibrosis (scarring of the liver). In this study, we describe their role in the modulation of fat deposition and inflammation in the liver, which occurs secondary to alcohol damage.
Authors: Cédric Coulouarn; Anne Corlu; Denise Glaise; Isabelle Guénon; Snorri S Thorgeirsson; Bruno Clément Journal: Cancer Res Date: 2012-03-14 Impact factor: 12.701
Authors: John T Heiker; Nora Klöting; Peter Kovacs; E Bartholomeus Kuettner; Norbert Sträter; Stephan Schultz; Matthias Kern; Michael Stumvoll; Matthias Blüher; Annette G Beck-Sickinger Journal: Cell Mol Life Sci Date: 2013-01-31 Impact factor: 9.261