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Ogoke O, Guiggey D, Mon T, Shamul C, Ross S, Rao S, Parashurama N. Spatiotemporal imaging and analysis of mouse and human liver bud morphogenesis. Dev Dyn 2021; 251:662-686. [PMID: 34665487 DOI: 10.1002/dvdy.429] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 09/07/2021] [Accepted: 09/28/2021] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND The process of liver organogenesis has served as a paradigm for organ formation. However, there remains a lack of understanding regarding early mouse and human liver bud morphogenesis and early liver volumetric growth. Elucidating dynamic changes in liver volumes is critical for understanding organ development, implementing toxicological studies, and for modeling hPSC-derived liver organoid growth. New visualization, analysis, and experimental techniques are desperately needed. RESULTS Here, we combine observational data with digital resources, new 3D imaging approaches, retrospective analysis of liver volume data, mathematical modeling, and experiments with hPSC-derived liver organoids. Mouse and human liver organogenesis, characterized by exponential growth, demonstrate distinct spatial features and growth curves over time, which we mathematically modeled using Gompertz models. Visualization of liver-epithelial and septum transversum mesenchyme (STM) interactions suggests extended interactions, which together with new spatial features may be responsible for extensive exponential growth. These STM interactions are modeled with a novel in vitro human pluripotent stem cell (hPSC)-derived hepatic organoid system that exhibits cell migration. CONCLUSIONS Our methods enhance our understanding of liver organogenesis, with new 3D visualization, analysis, mathematical modeling, and in vitro models with hPSCs. Our approach highlights mouse and human differences and provides potential hypothesis for further investigation in vitro and in vivo.
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Affiliation(s)
- Ogechi Ogoke
- Department of Chemical and Biological Engineering, University at Buffalo (State University of New York), Buffalo, New York, USA
| | - Daniel Guiggey
- Department of Chemical and Biological Engineering, University at Buffalo (State University of New York), Buffalo, New York, USA
| | - Tala Mon
- Department of Chemical and Biological Engineering, University at Buffalo (State University of New York), Buffalo, New York, USA
| | - Claire Shamul
- Department of Chemical and Biological Engineering, University at Buffalo (State University of New York), Buffalo, New York, USA
| | - Shatoni Ross
- Department of Chemical and Biological Engineering, University at Buffalo (State University of New York), Buffalo, New York, USA
| | - Saroja Rao
- Department of Biological Sciences, College of Arts and Sciences, University at Buffalo (State University of New York), Buffalo, New York, USA
| | - Natesh Parashurama
- Department of Chemical and Biological Engineering, University at Buffalo (State University of New York), Buffalo, New York, USA.,Clinical and Translation Research Center (CTRC), University at Buffalo (State University of New York), Buffalo, New York, USA.,Department of Biomedical Engineering, University at Buffalo (State University of New York), Buffalo, New York, USA.,Center for Cell, Gene, and Tissue Engineering (CGTE), University at Buffalo (State University of New York), Buffalo, New York, USA
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2
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Huo Z, Bilang R, Brantner B, von der Weid N, Holland-Cunz SG, Gros SJ. Perspective on Similarities and Possible Overlaps of Congenital Disease Formation-Exemplified on a Case of Congenital Diaphragmatic Hernia and Neuroblastoma in a Neonate. CHILDREN-BASEL 2021; 8:children8020163. [PMID: 33671521 PMCID: PMC7926624 DOI: 10.3390/children8020163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/17/2021] [Accepted: 02/17/2021] [Indexed: 11/25/2022]
Abstract
The coincidence of two rare diseases such as congenital diaphragmatic hernia (CDH) and neuroblastoma is exceptional. With an incidence of around 2–3:10,000 and 1:8000 for either disease occurring on its own, the chance of simultaneous presentation of both pathologies at birth is extremely low. Unfortunately, the underlying processes leading to congenital malformation and neonatal tumors are not yet thoroughly understood. There are several hypotheses revolving around the formation of CDH and neuroblastoma. The aim of our study was to put the respective hypotheses of disease formation as well as known factors in this process into perspective regarding their similarities and possible overlaps of congenital disease formation. We present the joint occurrence of these two rare diseases based on a patient presentation and immunochemical prognostic marker evaluation. The aim of this manuscript is to elucidate possible similarities in the pathogeneses of both disease entities. Discussed are the role of toxins, cell differentiation, the influence of retinoic acid and NMYC as well as of hypoxia. The detailed discussion reveals that some of the proposed pathophysiological mechanisms of both malformations have common aspects. Especially disturbances of the retinoic acid pathway and NMYC expression can influence and disrupt cell differentiation in either disease. Due to the rarity of both diseases, interdisciplinary efforts and multi-center studies are needed to investigate the reasons for congenital malformations and their interlinkage with neonatal tumor disease.
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Affiliation(s)
- Zihe Huo
- Department of Pediatric Surgery, University Children’s Hospital Basel, 4031 Basel, Switzerland; (Z.H.); (R.B.); (B.B.); (S.G.H.-C.)
- Department of Clinical Research, University of Basel, 4001 Basel, Switzerland;
| | - Remo Bilang
- Department of Pediatric Surgery, University Children’s Hospital Basel, 4031 Basel, Switzerland; (Z.H.); (R.B.); (B.B.); (S.G.H.-C.)
- Department of Clinical Research, University of Basel, 4001 Basel, Switzerland;
| | - Benedikt Brantner
- Department of Pediatric Surgery, University Children’s Hospital Basel, 4031 Basel, Switzerland; (Z.H.); (R.B.); (B.B.); (S.G.H.-C.)
| | - Nicolas von der Weid
- Department of Clinical Research, University of Basel, 4001 Basel, Switzerland;
- Department of Hematology and Oncology, University Children’s Hospital Basel, 4056 Basel, Switzerland
| | - Stefan G. Holland-Cunz
- Department of Pediatric Surgery, University Children’s Hospital Basel, 4031 Basel, Switzerland; (Z.H.); (R.B.); (B.B.); (S.G.H.-C.)
- Department of Clinical Research, University of Basel, 4001 Basel, Switzerland;
| | - Stephanie J. Gros
- Department of Pediatric Surgery, University Children’s Hospital Basel, 4031 Basel, Switzerland; (Z.H.); (R.B.); (B.B.); (S.G.H.-C.)
- Department of Clinical Research, University of Basel, 4001 Basel, Switzerland;
- Correspondence:
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3
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Yang L, Li LC, Wang X, Wang WH, Wang YC, Xu CR. The contributions of mesoderm-derived cells in liver development. Semin Cell Dev Biol 2018; 92:63-76. [PMID: 30193996 DOI: 10.1016/j.semcdb.2018.09.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 08/31/2018] [Accepted: 09/02/2018] [Indexed: 02/07/2023]
Abstract
The liver is an indispensable organ for metabolism and drug detoxification. The liver consists of endoderm-derived hepatobiliary lineages and various mesoderm-derived cells, and interacts with the surrounding tissues and organs through the ventral mesentery. Liver development, from hepatic specification to liver maturation, requires close interactions with mesoderm-derived cells, such as mesothelial cells, hepatic stellate cells, mesenchymal cells, liver sinusoidal endothelial cells and hematopoietic cells. These cells affect liver development through precise signaling events and even direct physical contact. Through the use of new techniques, emerging studies have recently led to a deeper understanding of liver development and its related mechanisms, especially the roles of mesodermal cells in liver development. Based on these developments, the current protocols for in vitro hepatocyte-like cell induction and liver-like tissue construction have been optimized and are of great importance for the treatment of liver diseases. Here, we review the roles of mesoderm-derived cells in the processes of liver development, hepatocyte-like cell induction and liver-like tissue construction.
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Affiliation(s)
- Li Yang
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking-Tsinghua Center for Life Sciences, China; Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China
| | - Lin-Chen Li
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking-Tsinghua Center for Life Sciences, China; Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China
| | - Xin Wang
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking-Tsinghua Center for Life Sciences, China
| | - Wei-Hua Wang
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking-Tsinghua Center for Life Sciences, China; Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China
| | - Yan-Chun Wang
- Haidian Maternal & Child Health Hospital, Beijing, 100080, China
| | - Cheng-Ran Xu
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking-Tsinghua Center for Life Sciences, China.
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4
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Ober EA, Lemaigre FP. Development of the liver: Insights into organ and tissue morphogenesis. J Hepatol 2018; 68:1049-1062. [PMID: 29339113 DOI: 10.1016/j.jhep.2018.01.005] [Citation(s) in RCA: 140] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 12/29/2017] [Accepted: 01/06/2018] [Indexed: 02/08/2023]
Abstract
Recent development of improved tools and methods to analyse tissues at the three-dimensional level has expanded our capacity to investigate morphogenesis of foetal liver. Here, we review the key morphogenetic steps during liver development, from the prehepatic endoderm stage to the postnatal period, and consider several model organisms while focussing on the mammalian liver. We first discuss how the liver buds out of the endoderm and gives rise to an asymmetric liver. We next outline the mechanisms driving liver and lobe growth, and review morphogenesis of the intra- and extrahepatic bile ducts; morphogenetic responses of the biliary tract to liver injury are discussed. Finally, we describe the mechanisms driving formation of the vasculature, namely venous and arterial vessels, as well as sinusoids.
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Affiliation(s)
- Elke A Ober
- Novo Nordisk Center for Stem Cell Biology (DanStem), University of Copenhagen, Copenhagen, Denmark
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5
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Petry B, Savoldi IR, Ibelli AMG, Paludo E, de Oliveira Peixoto J, Jaenisch FRF, de Córdova Cucco D, Ledur MC. New genes involved in the Bacterial Chondronecrosis with Osteomyelitis in commercial broilers. Livest Sci 2018. [DOI: 10.1016/j.livsci.2017.12.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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6
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Trevaskis JL, Sacramento CB, Jouihan H, Ali S, Le Lay J, Oldham S, Bhagroo N, Boland BB, Cann J, Chang Y, O'Day T, Howard V, Reers C, Winzell MS, Smith DM, Feigh M, Barkholt P, Schreiter K, Austen M, Andag U, Thompson S, Jermutus L, Coghlan MP, Grimsby J, Dohrmann C, Rhodes CJ, Rondinone CM, Sharma A. Neurturin and a GLP-1 Analogue Act Synergistically to Alleviate Diabetes in Zucker Diabetic Fatty Rats. Diabetes 2017; 66:2007-2018. [PMID: 28408435 DOI: 10.2337/db16-0916] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 04/05/2017] [Indexed: 11/13/2022]
Abstract
Neurturin (NRTN), a member of the glial-derived neurotrophic factor family, was identified from an embryonic chicken pancreatic cDNA library in a screen for secreted factors. In this study, we assessed the potential antidiabetic activities of NRTN relative to liraglutide, a glucagon-like peptide 1 receptor agonist, in Zucker diabetic fatty (ZDF) rats. Subcutaneous administration of NRTN to 8-week-old male ZDF rats prevented the development of hyperglycemia and improved metabolic parameters similar to liraglutide. NRTN treatment increased pancreatic insulin content and β-cell mass and prevented deterioration of islet organization. However, unlike liraglutide-treated rats, NRTN-mediated improvements were not associated with reduced body weight or food intake. Acute NRTN treatment did not activate c-Fos expression in key feeding behavior and metabolic centers in ZDF rat brain or directly enhance glucose-stimulated insulin secretion from pancreatic β-cells. Treating 10-week-old ZDF rats with sustained hyperglycemia with liraglutide resulted in some alleviation of hyperglycemia, whereas NRTN was not as effective despite improving plasma lipids and fasting glucose levels. Interestingly, coadministration of NRTN and liraglutide normalized hyperglycemia and other metabolic parameters, demonstrating that combining therapies with distinct mechanism(s) can alleviate advanced diabetes. This emphasizes that therapeutic combinations can be more effective to manage diabetes in individuals with uncontrolled hyperglycemia.
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Affiliation(s)
- James L Trevaskis
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | | | - Hani Jouihan
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Safina Ali
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - John Le Lay
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Stephanie Oldham
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Nicholas Bhagroo
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Brandon B Boland
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Jennifer Cann
- Translational Sciences (Pathology), MedImmune LLC, Gaithersburg, MD
| | - Yuan Chang
- Biopharmaceutical Development, MedImmune LLC, Gaithersburg, MD
| | | | - Victor Howard
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | | | | | - David M Smith
- Discovery Sciences, Innovative Medicines & Early Development Biotech Unit, AstraZeneca, Cambridge, U.K
| | | | | | | | | | | | - Simon Thompson
- Research Project and Portfolio Management, MedImmune Ltd., Cambridge, U.K
| | - Lutz Jermutus
- Department of Cardiovascular and Metabolic Diseases, MedImmune Ltd., Cambridge, U.K
| | - Matthew P Coghlan
- Department of Cardiovascular and Metabolic Diseases, MedImmune Ltd., Cambridge, U.K
| | - Joseph Grimsby
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | | | - Christopher J Rhodes
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Cristina M Rondinone
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
| | - Arun Sharma
- Department of Cardiovascular and Metabolic Diseases, MedImmune LLC, Gaithersburg, MD
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7
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Arterbery AS, Bogue CW. Endodermal and mesenchymal cross talk: a crossroad for the maturation of foregut organs. Pediatr Res 2014; 75:120-6. [PMID: 24192700 DOI: 10.1038/pr.2013.201] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 08/27/2013] [Indexed: 01/30/2023]
Abstract
The developmental stages of each foregut organ are intimately linked to the development of the other foregut organs such that the ultimate function of any one foregut organ, such as the metabolic function of the liver, depends on organizational changes associated with the maturation of multiple foregut organs. These changes include: (i) proliferation of the intrahepatic bile ducts and hepatoblasts within the liver coinciding with parenchymal expansion, (ii) elongation of extrahepatic bile ducts, which allows for proper gallbladder (GB) formation, and (iii) duodenal elongation and rotation, which coincides with all of the above to connect the intrahepatic, extrahepatic, and pancreatic ductal systems with the intestine. It is well established that cross talk between endodermal and mesenchymal components of the foregut occurs, particularly regarding the vascularization of developing organs. Furthermore, genetic mutations in mesenchymal and hepatic compartments of the developing foregut result in similar foregut pathologies: hypoplastic liver, absence of GB, biliary atresia (intrahepatic and/or extrahepatic), and failure of gut elongation and rotation. Finally, these shared pathologies can be linked to deficiencies in genes specific to the septum transversum mesenchyme (Hes1, Hlx, and Foxf1) or liver (Hhex and Hnf6), illustrating the complexity of such cross talk.
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Affiliation(s)
- Adam S Arterbery
- Department of Pediatrics, Yale School of Medicine, New Haven, Connecticut
| | - Clifford W Bogue
- Department of Pediatrics, Yale School of Medicine, New Haven, Connecticut
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8
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Abstract
Liver is a prime organ responsible for synthesis, metabolism, and detoxification. The organ is endodermal in origin and its development is regulated by temporal, complex, and finely balanced cellular and molecular interactions that dictate its origin, growth, and maturation. We discuss the relevance of endoderm patterning, which truly is the first step toward mapping of domains that will give rise to specific organs. Once foregut patterning is completed, certain cells within the foregut endoderm gain competence in the form of expression of certain transcription factors that allow them to respond to certain inductive signals. Hepatic specification is then a result of such inductive signals, which often emanate from the surrounding mesenchyme. During hepatic specification bipotential hepatic stem cells or hepatoblasts become apparent and undergo expansion, which results in a visible liver primordium during the stage of hepatic morphogenesis. Hepatoblasts next differentiate into either hepatocytes or cholangiocytes. The expansion and differentiation is regulated by cellular and molecular interactions between hepatoblasts and mesenchymal cells including sinusoidal endothelial cells, stellate cells, and also innate hematopoietic elements. Further maturation of hepatocytes and cholangiocytes continues during late hepatic development as a function of various growth factors. At this time, liver gains architectural novelty in the form of zonality and at cellular level acquires polarity. A comprehensive elucidation of such finely tuned developmental cues have been the basis of transdifferentiation of various types of stem cells to hepatocyte-like cells for purposes of understanding health and disease and for therapeutic applications.
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Affiliation(s)
- Donghun Shin
- Department of Developmental Biology, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania, USA.
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9
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Morris MW, Helling TS, Creswell LL, Jordan B, Mitchell ME. Ectopic liver masquerading as a floating intracaval mass. J Vasc Surg 2012; 55:1759-61. [PMID: 22360917 DOI: 10.1016/j.jvs.2011.12.064] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 12/09/2011] [Accepted: 12/24/2011] [Indexed: 12/17/2022]
Abstract
Ectopic liver is defined as liver parenchyma situated outside the liver proper with no connection to native hepatic tissue. This rare developmental anomaly is most commonly described as an attachment to the gallbladder with an incidence <0.3%, but it has been reported in other locations within the abdomen and thorax.(2-4) Most cases are found incidentally in asymptomatic patients, but ectopic liver has been known to cause visceral or vascular obstruction.(4,5) Herein we present a unique case of ectopic liver attached by a thin stalk seemingly floating in the suprahepatic inferior vena cava.
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Affiliation(s)
- Michael Wyatt Morris
- Department of Surgery, University of Mississippi Medical Center, Jackson, MS 39216, USA.
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10
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DeLeve LD, Jaeschke H, Kalra VK, Asahina K, Brenner DA, Tsukamoto H. 15th International Symposium on Cells of the Hepatic Sinusoid, 2010. Liver Int 2011; 31:762-72. [PMID: 21645207 PMCID: PMC4388239 DOI: 10.1111/j.1478-3231.2011.02527.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
This is a meeting report of the presentations given at the 15th International Symposium on Cells of the Hepatic Sinusoid, held in 2010. The areas covered include the contributions of the various liver cell populations to liver disease, molecular and cellular targets involved in steatohepatitis, hepatic fibrosis and cancer and regenerative medicine. In addition to a review of the science presented at the meeting, this report provides references to recent literature on the topics covered at the meeting.
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Affiliation(s)
- Laurie D DeLeve
- Division of Gastrointestinal and Liver Diseases, University of Southern California Keck School of Medicine, Los Angeles, CA 90069, USA.
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11
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Lade AG, Monga SPS. Beta-catenin signaling in hepatic development and progenitors: which way does the WNT blow? Dev Dyn 2010; 240:486-500. [PMID: 21337461 DOI: 10.1002/dvdy.22522] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/15/2010] [Indexed: 12/19/2022] Open
Abstract
The Wnt/β-catenin pathway is an evolutionarily conserved signaling cascade that plays key roles in development and adult tissue homeostasis and is aberrantly activated in many tumors. Over a decade of work in mouse, chick, xenopus, and zebrafish models has uncovered multiple functions of this pathway in hepatic pathophysiology. Specifically, beta-catenin, the central component of the canonical Wnt pathway, is implicated in the regulation of liver regeneration, development, and carcinogenesis. Wnt-independent activation of beta-catenin by receptor tyrosine kinases has also been observed in the liver. In liver development across various species, through regulation of cell proliferation, differentiation, and maturation, beta-catenin directs foregut endoderm specification, hepatic specification of the foregut, and hepatic morphogenesis. Its role has also been defined in adult hepatic progenitors or oval cells especially in their expansion and differentiation. Thus, beta-catenin undergoes tight temporal regulation to exhibit pleiotropic effects during hepatic development and in hepatic progenitor biology.
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12
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Margagliotti S, Clotman F, Pierreux CE, Lemoine P, Rousseau GG, Henriet P, Lemaigre FP. Role of metalloproteinases at the onset of liver development. Dev Growth Differ 2008; 50:331-8. [PMID: 18445063 DOI: 10.1111/j.1440-169x.2008.01031.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
At the onset of liver development, the hepatic precursor cells, namely, the hepatoblasts, derive from the ventral foregut endoderm and form a bud surrounded by a basement membrane (BM). To initiate liver growth, the hepatoblasts migrate across the BM and invade the neighboring septum transversum mesenchyme. In the present study, carried out in the mouse embryo, we searched for effectors involved in this process and we examined the role of matrix metalloproteinases (MMPs). We found expression of a broad range of MMPs, among which MMP-2 was predominantly expressed in the septum transversum and MMP-14 in the hepatoblasts. Using a new liver explant culture system we showed that inhibition of MMP activity represses migration of the hepatoblasts. We conclude that MMPs are required to initiate expansion of the liver during development and that our culture system provides a new model to study hepatoblast migration.
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Affiliation(s)
- Sabrina Margagliotti
- Hormone and Metabolic Research Unit, Université Catholique de Louvain, de Duve Institute, 1200 Brussels, Belgium
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Wnt9a secreted from the walls of hepatic sinusoids is essential for morphogenesis, proliferation, and glycogen accumulation of chick hepatic epithelium. Dev Biol 2008; 319:234-47. [PMID: 18513713 DOI: 10.1016/j.ydbio.2008.04.021] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2007] [Revised: 03/25/2008] [Accepted: 04/03/2008] [Indexed: 11/22/2022]
Abstract
Hepatic epithelial morphogenesis, including hepatoblast migration and proliferation in the septum transversum, requires the interaction of hepatic epithelium with the embryonic sinusoidal wall. No factors that mediate this interaction have yet been identified. As the beta-catenin pathway is active in hepatoblast proliferation, then Wnt ligands might activate the canonical Wnt pathway during liver development. Here, we investigated the role of Wnts in mediating epithelial vessel interactions in the developing chick liver. We found that Wnt9a was specifically expressed in both endothelial and stellate cells of the embryonic sinusoidal wall. Induced overexpression of Wnt9a resulted in hepatomegaly with hyperplasia of the hepatocellular cords, and in hyperproliferation of hepatocytes. Knockdown of Wnt9a caused a reduction in liver size, with hypoplasia of hepatocellular cord branching, and hypoproliferation of hepatoblasts, and also inhibited glycogen accumulation at later developmental stages. Wnt9a promoted in vivo stabilization of beta-catenin through binding with Frizzled 4, 7, and 9, and activated TOPflash reporter expression in vitro via Frizzled 7 and 9. Our results demonstrate that Wnt9a from the embryonic sinusoidal wall is required for the proper morphogenesis of chick hepatocellular cords, proliferation of hepatoblasts/hepatocytes, and glycogen accumulation in hepatocytes. Wnt9a signaling appears to be mediated by an Fzd7/9-beta-catenin pathway.
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