Xu-Feng Lu1, Yong-Jie Zhou1, Lei Zhang1, Hong-Jie Ji1, Li Li1, Yu-Jun Shi1, Hong Bu1. 1. Xu-Feng Lu, Yong-Jie Zhou, Lei Zhang, Hong-Jie Ji, Li Li, Yu-Jun Shi, Hong Bu, Laboratory of Pathology, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China.
Abstract
AIM: To investigate the continuous hepatic histopathological processes which occur in response to the loss of Dicer1. METHODS: We generated a hepatocyte-selective Dicer1 knockout mouse and observed the gradual hepatic histopathological changes in the mutant liver. Immunohistochemistry and Western blotting were performed to detect Dicer1 expression. We performed hematoxylin and eosin staining, Periodic acid-Schiff staining, Oil Red O staining, and Masson's trichrome staining to detect histological changes in Dicer1-deficient livers. Ki67 immunohistochemistry, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay, and Western blotting were used to determine hepatocyte proliferation and apoptosis. Serum biochemistry, cytokine assays, and flow cytometric analysis were performed to quantity liver necrosis and inflammation. Fibrogenic markers were determined by Western blotting and qPCR. CK19, CD133, and OV6 immunofluorescence were used to observe liver progenitor cells. Immunofluorescence and qPCR were performed to reveal embryonic gene expression. We also performed histological staining and Western blotting to analyze hepatocellular carcinoma (HCC) development. RESULTS: Dicer1 inactivation resulted in significant architecture disorganization and metabolism disruption in the liver. Dicer1 disruption impaired hepatocyte survival and resulted in profound cell apoptosis and continuous necrosis. In contrast to previous reports, the mutant liver exhibited chronic inflammation and progressive fibrosis, and could not be repopulated by Dicer1-positive cells. In addition, extensive activation of hepatic progenitor cells was observed. Primary HCC was observed as early as 4 mo after birth. CONCLUSION: Hepatic loss of Dicer1 results in complex chronic pathological processes, including hepatocyte death, inflammatory infiltration, chronic fibrosis, compensatory proliferation, progenitor activation, and spontaneous hepatocarcinogenesis.
AIM: To investigate the continuous hepatic histopathological processes which occur in response to the loss of Dicer1. METHODS: We generated a hepatocyte-selective Dicer1 knockout mouse and observed the gradual hepatic histopathological changes in the mutant liver. Immunohistochemistry and Western blotting were performed to detect Dicer1 expression. We performed hematoxylin and eosin staining, Periodic acid-Schiff staining, Oil Red O staining, and Masson's trichrome staining to detect histological changes in Dicer1-deficient livers. Ki67 immunohistochemistry, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay, and Western blotting were used to determine hepatocyte proliferation and apoptosis. Serum biochemistry, cytokine assays, and flow cytometric analysis were performed to quantity liver necrosis and inflammation. Fibrogenic markers were determined by Western blotting and qPCR. CK19, CD133, and OV6 immunofluorescence were used to observe liver progenitor cells. Immunofluorescence and qPCR were performed to reveal embryonic gene expression. We also performed histological staining and Western blotting to analyze hepatocellular carcinoma (HCC) development. RESULTS:Dicer1 inactivation resulted in significant architecture disorganization and metabolism disruption in the liver. Dicer1 disruption impaired hepatocyte survival and resulted in profound cell apoptosis and continuous necrosis. In contrast to previous reports, the mutant liver exhibited chronic inflammation and progressive fibrosis, and could not be repopulated by Dicer1-positive cells. In addition, extensive activation of hepatic progenitor cells was observed. Primary HCC was observed as early as 4 mo after birth. CONCLUSION: Hepatic loss of Dicer1 results in complex chronic pathological processes, including hepatocyte death, inflammatory infiltration, chronic fibrosis, compensatory proliferation, progenitor activation, and spontaneous hepatocarcinogenesis.
Authors: Carlo Schneider; Andreas Teufel; Tetyana Yevsa; Frank Staib; Anja Hohmeyer; Gudrun Walenda; Henning W Zimmermann; Mihael Vucur; Sebastian Huss; Nikolaus Gassler; Hermann E Wasmuth; Sergio A Lira; Lars Zender; Tom Luedde; Christian Trautwein; Frank Tacke Journal: Gut Date: 2012-01-20 Impact factor: 23.059
Authors: Christine Esau; Scott Davis; Susan F Murray; Xing Xian Yu; Sanjay K Pandey; Michael Pear; Lynnetta Watts; Sheri L Booten; Mark Graham; Robert McKay; Amuthakannan Subramaniam; Stephanie Propp; Bridget A Lollo; Susan Freier; C Frank Bennett; Sanjay Bhanot; Brett P Monia Journal: Cell Metab Date: 2006-02 Impact factor: 27.287