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Ma J, Tan X, Kwon Y, Delgado ER, Zarnegar A, DeFrances MC, Duncan AW, Zarnegar R. A Novel Humanized Model of NASH and Its Treatment With META4, A Potent Agonist of MET. Cell Mol Gastroenterol Hepatol 2021; 13:565-582. [PMID: 34756982 PMCID: PMC8688725 DOI: 10.1016/j.jcmgh.2021.10.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 10/12/2021] [Accepted: 10/13/2021] [Indexed: 12/10/2022]
Abstract
BACKGROUND & AIMS Nonalcoholic fatty liver disease is a frequent cause of hepatic dysfunction and is now a global epidemic. This ailment can progress to an advanced form called nonalcoholic steatohepatitis (NASH) and end-stage liver disease. Currently, the molecular basis of NASH pathogenesis is poorly understood, and no effective therapies exist to treat NASH. These shortcomings are due to the paucity of experimental NASH models directly relevant to humans. METHODS We used chimeric mice with humanized liver to investigate nonalcoholic fatty liver disease in a relevant model. We carried out histologic, biochemical, and molecular approaches including RNA-Seq. For comparison, we used side-by-side human NASH samples. RESULTS Herein, we describe a "humanized" model of NASH using transplantation of human hepatocytes into fumarylacetoacetate hydrolase-deficient mice. Once fed a high-fat diet, these mice develop NAFLD faithfully, recapitulating human NASH at the histologic, cellular, biochemical, and molecular levels. Our RNA-Seq analyses uncovered that a variety of important signaling pathways that govern liver homeostasis are profoundly deregulated in both humanized and human NASH livers. Notably, we made the novel discovery that hepatocyte growth factor (HGF) function is compromised in human and humanized NASH at several levels including a significant increase in the expression of the HGF antagonists known as NK1/NK2 and marked decrease in HGF activator. Based on these observations, we generated a potent, human-specific, and stable agonist of human MET that we have named META4 (Metaphor) and used it in the humanized NASH model to restore HGF function. CONCLUSIONS Our studies revealed that the humanized NASH model recapitulates human NASH and uncovered that HGF-MET function is impaired in this disease. We show that restoring HGF-MET function by META4 therapy ameliorates NASH and reinstates normal liver function in the humanized NASH model. Our results show that the HGF-MET signaling pathway is a dominant regulator of hepatic homeostasis.
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Affiliation(s)
- Jihong Ma
- The Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Xinping Tan
- The Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Yongkook Kwon
- The Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Evan R. Delgado
- The Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania 15261,Pittsburgh Liver Research Center, School of Medicine, Pittsburgh, Pennsylvania,McGowan Institute of Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Arman Zarnegar
- The Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Marie C. DeFrances
- The Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania 15261,Pittsburgh Liver Research Center, School of Medicine, Pittsburgh, Pennsylvania,McGowan Institute of Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Andrew W. Duncan
- The Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania 15261,Pittsburgh Liver Research Center, School of Medicine, Pittsburgh, Pennsylvania,McGowan Institute of Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Reza Zarnegar
- The Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania 15261,Pittsburgh Liver Research Center, School of Medicine, Pittsburgh, Pennsylvania,McGowan Institute of Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania,Correspondence Address correspondence to: Prof Reza Zarnegar, University of Pittsburgh, Department of Pathology, 200 Lothrop St, Pittsburgh, Pennsylvania 15261. tel: (412) 648-8657; fax: (412) 648-1916.
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