1
|
Gao J, Zuo B, He Y. Liver sinusoidal endothelial cells as potential drivers of liver fibrosis (Review). Mol Med Rep 2024; 29:40. [PMID: 38240102 PMCID: PMC10828992 DOI: 10.3892/mmr.2024.13164] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 12/18/2023] [Indexed: 01/23/2024] Open
Abstract
Liver fibrosis due to viral or metabolic chronic liver diseases is a major challenge of global health. It is a critical pre‑stage condition of severe hepatopathy, characterized by excessive accumulation of extracellular matrix components and ongoing chronic inflammation. To date, early prevention of liver fibrosis remains challenging. As the most abundant non‑parenchymal hepatic cell population, liver sinusoidal endothelial cells (LSECs) are stabilizers that maintain the intrahepatic environment. Notably, LSECs dysfunction appears to be implicated in the progression of liver fibrosis via numerous mechanisms. Following sustained liver injury, they lose their fenestrae (cytoplasmic pores) and change their crosstalk with other cellular interactions in the hepatic blood environment. LSEC‑targeted therapy has shown promising effects on fibrosis resolution, opening up new opportunities for anti‑fibrotic therapy. In light of this, the present study summarized changes in LSECs during liver fibrosis and their interactions with hepatic milieu, as well as possible therapeutic approaches that specially target LSECs.
Collapse
Affiliation(s)
- Jiaqin Gao
- National Health Commission Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
- Ministry of Education Engineering Center of Hematological Disease, Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, Jiangsu 215123, P.R. China
| | - Bin Zuo
- National Health Commission Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
- Ministry of Education Engineering Center of Hematological Disease, Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, Jiangsu 215123, P.R. China
| | - Yang He
- National Health Commission Key Laboratory of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, P.R. China
| |
Collapse
|
2
|
Dabaghi M, Carpio MB, Saraei N, Moran-Mirabal JM, Kolb MR, Hirota JA. A roadmap for developing and engineering in vitro pulmonary fibrosis models. BIOPHYSICS REVIEWS 2023; 4:021302. [PMID: 38510343 PMCID: PMC10903385 DOI: 10.1063/5.0134177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 04/03/2023] [Indexed: 03/22/2024]
Abstract
Idiopathic pulmonary fibrosis (IPF) is a severe form of pulmonary fibrosis. IPF is a fatal disease with no cure and is challenging to diagnose. Unfortunately, due to the elusive etiology of IPF and a late diagnosis, there are no cures for IPF. Two FDA-approved drugs for IPF, nintedanib and pirfenidone, slow the progression of the disease, yet fail to cure or reverse it. Furthermore, most animal models have been unable to completely recapitulate the physiology of human IPF, resulting in the failure of many drug candidates in preclinical studies. In the last few decades, the development of new IPF drugs focused on changes at the cellular level, as it was believed that the cells were the main players in IPF development and progression. However, recent studies have shed light on the critical role of the extracellular matrix (ECM) in IPF development, where the ECM communicates with cells and initiates a positive feedback loop to promote fibrotic processes. Stemming from this shift in the understanding of fibrosis, there is a need to develop in vitro model systems that mimic the human lung microenvironment to better understand how biochemical and biomechanical cues drive fibrotic processes in IPF. However, current in vitro cell culture platforms, which may include substrates with different stiffness or natural hydrogels, have shortcomings in recapitulating the complexity of fibrosis. This review aims to draw a roadmap for developing advanced in vitro pulmonary fibrosis models, which can be leveraged to understand better different mechanisms involved in IPF and develop drug candidates with improved efficacy. We begin with a brief overview defining pulmonary fibrosis and highlight the importance of ECM components in the disease progression. We focus on fibroblasts and myofibroblasts in the context of ECM biology and fibrotic processes, as most conventional advanced in vitro models of pulmonary fibrosis use these cell types. We transition to discussing the parameters of the 3D microenvironment that are relevant in pulmonary fibrosis progression. Finally, the review ends by summarizing the state of the art in the field and future directions.
Collapse
Affiliation(s)
- Mohammadhossein Dabaghi
- Firestone Institute for Respiratory Health—Division of Respirology, Department of Medicine, McMaster University, St. Joseph's Healthcare Hamilton, 50 Charlton Avenue East, Hamilton, Ontario L8N 4A6, Canada
| | - Mabel Barreiro Carpio
- Department of Chemistry and Chemical Biology, McMaster University, Arthur N. Bourns Science Building, 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
| | - Neda Saraei
- School of Biomedical Engineering, McMaster University, Engineering Technology Building, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada
| | | | - Martin R. Kolb
- Firestone Institute for Respiratory Health—Division of Respirology, Department of Medicine, McMaster University, St. Joseph's Healthcare Hamilton, 50 Charlton Avenue East, Hamilton, Ontario L8N 4A6, Canada
| | | |
Collapse
|
3
|
Dooling LJ, Saini K, Anlaş AA, Discher DE. Tissue mechanics coevolves with fibrillar matrisomes in healthy and fibrotic tissues. Matrix Biol 2022; 111:153-188. [PMID: 35764212 PMCID: PMC9990088 DOI: 10.1016/j.matbio.2022.06.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 06/16/2022] [Accepted: 06/23/2022] [Indexed: 12/12/2022]
Abstract
Fibrillar proteins are principal components of extracellular matrix (ECM) that confer mechanical properties to tissues. Fibrosis can result from wound repair in nearly every tissue in adults, and it associates with increased ECM density and crosslinking as well as increased tissue stiffness. Such fibrotic tissues are a major biomedical challenge, and an emerging view posits that the altered mechanical environment supports both synthetic and contractile myofibroblasts in a state of persistent activation. Here, we review the matrisome in several fibrotic diseases, as well as normal tissues, with a focus on physicochemical properties. Stiffness generally increases with the abundance of fibrillar collagens, the major constituent of ECM, with similar mathematical trends for fibrosis as well as adult tissues from soft brain to stiff bone and heart development. Changes in expression of other core matrisome and matrisome-associated proteins or proteoglycans contribute to tissue stiffening in fibrosis by organizing collagen, crosslinking ECM, and facilitating adhesion of myofibroblasts. Understanding how ECM composition and mechanics coevolve during fibrosis can lead to better models and help with antifibrotic therapies.
Collapse
Affiliation(s)
- Lawrence J Dooling
- Molecular and Cellular Biophysics Lab, University of Pennsylvania,Philadelphia, PA 19104, USA
| | - Karanvir Saini
- Molecular and Cellular Biophysics Lab, University of Pennsylvania,Philadelphia, PA 19104, USA
| | - Alişya A Anlaş
- Molecular and Cellular Biophysics Lab, University of Pennsylvania,Philadelphia, PA 19104, USA
| | - Dennis E Discher
- Molecular and Cellular Biophysics Lab, University of Pennsylvania,Philadelphia, PA 19104, USA.
| |
Collapse
|
4
|
Li H. Intercellular crosstalk of liver sinusoidal endothelial cells in liver fibrosis, cirrhosis and hepatocellular carcinoma. Dig Liver Dis 2022; 54:598-613. [PMID: 34344577 DOI: 10.1016/j.dld.2021.07.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 07/09/2021] [Accepted: 07/12/2021] [Indexed: 12/12/2022]
Abstract
Intercellular crosstalk among various liver cells plays an important role in liver fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Capillarization of liver sinusoidal endothelial cells (LSECs) precedes fibrosis and accumulating evidence suggests that the crosstalk between LSECs and other liver cells is critical in the development and progression of liver fibrosis. LSECs dysfunction, a key event in the progression from fibrosis to cirrhosis, and subsequently obstruction of hepatic sinuses and increased intrahepatic vascular resistance (IHVR) contribute to development of portal hypertension (PHT) and cirrhosis. More importantly, immunosuppressive tumor microenvironment (TME), which is closely related to the crosstalk between LSECs and immune liver cells like CD8+ T cells, promotes advances tumorigenesis, especially HCC. However, the connections within the crosstalk between LSECs and other liver cells during the progression from liver fibrosis to cirrhosis to HCC have yet to be discussed. In this review, we first summarize the current knowledge of how different crosstalk between LSECs and other liver cells, including hepatocytes, hepatic stellate cells (HSCs), macrophoges, immune cells in liver and extra cellular matrix (ECM) contribute to the physiological function and the progrssion from liver fibrosis to cirrhosis, or even to HCC. Then we examine current treatment strategies for LSECs crosstalk in liver fibrosis, cirrhosis and HCC.
Collapse
Affiliation(s)
- Hui Li
- Central Laboratory, Hospital of Chengdu University of Traditional Chinese Medicine, NO. 39 Shi-er-qiao Road, Chengdu, 610072, Sichuan Province, PR China.
| |
Collapse
|
5
|
Schinagl M, Tomin T, Gindlhuber J, Honeder S, Pfleger R, Schittmayer M, Trauner M, Birner-Gruenberger R. Proteomic Changes of Activated Hepatic Stellate Cells. Int J Mol Sci 2021; 22:ijms222312782. [PMID: 34884585 PMCID: PMC8657869 DOI: 10.3390/ijms222312782] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/18/2021] [Accepted: 11/23/2021] [Indexed: 12/15/2022] Open
Abstract
Hepatic stellate cells (HSC) are the major cellular drivers of liver fibrosis. Upon liver inflammation caused by a broad range of insults including non-alcoholic fatty liver, HSC transform from a quiescent into a proliferating, fibrotic phenotype. Although much is known about the pathophysiology of this process, exact cellular processes which occur in HSC and enable this transformation remain yet to be elucidated. In order to investigate this HSC transformation, we employed a simple, yet reliable model of HSC activation via an increase in growth medium serum concentration (serum activation). For that purpose, immortalized human LX-2 HSC were exposed to either 1% or 10% fetal bovine serum (FBS). Resulting quiescent (1% FBS) and activated (10% FBS) LX-2 cells were then subjected to in-depth mass spectrometry-based proteomics analysis as well as comprehensive phenotyping. Protein network analysis of activated LX-2 cells revealed an increase in the production of ribosomal proteins and proteins related to cell cycle control and migration, resulting in higher proliferation and faster migration phenotypes. Interestingly, we also observed a decrease in the expression of cholesterol and fatty acid biosynthesis proteins in accordance with a concomitant loss of cytosolic lipid droplets during activation. Overall, this work provides an update on HSC activation characteristics using contemporary proteomic and bioinformatic analyses and presents an accessible model for HSC activation. Data are available via ProteomeXchange with identifier PXD029121.
Collapse
Affiliation(s)
- Maximilian Schinagl
- Institute of Chemical Technologies and Analytics, Technische Universität Wien, 1060 Vienna, Austria; (M.S.); (T.T.); (R.P.); (M.S.)
- Department of Pathology, Medical University of Graz, 8010 Graz, Austria; (J.G.); (S.H.)
| | - Tamara Tomin
- Institute of Chemical Technologies and Analytics, Technische Universität Wien, 1060 Vienna, Austria; (M.S.); (T.T.); (R.P.); (M.S.)
| | - Juergen Gindlhuber
- Department of Pathology, Medical University of Graz, 8010 Graz, Austria; (J.G.); (S.H.)
| | - Sophie Honeder
- Department of Pathology, Medical University of Graz, 8010 Graz, Austria; (J.G.); (S.H.)
| | - Raphael Pfleger
- Institute of Chemical Technologies and Analytics, Technische Universität Wien, 1060 Vienna, Austria; (M.S.); (T.T.); (R.P.); (M.S.)
| | - Matthias Schittmayer
- Institute of Chemical Technologies and Analytics, Technische Universität Wien, 1060 Vienna, Austria; (M.S.); (T.T.); (R.P.); (M.S.)
| | - Michael Trauner
- Hans Popper Laboratory of Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria;
| | - Ruth Birner-Gruenberger
- Institute of Chemical Technologies and Analytics, Technische Universität Wien, 1060 Vienna, Austria; (M.S.); (T.T.); (R.P.); (M.S.)
- Department of Pathology, Medical University of Graz, 8010 Graz, Austria; (J.G.); (S.H.)
- Correspondence:
| |
Collapse
|
6
|
Wu X, Shu L, Zhang Z, Li J, Zong J, Cheong LY, Ye D, Lam KSL, Song E, Wang C, Xu A, Hoo RLC. Adipocyte Fatty Acid Binding Protein Promotes the Onset and Progression of Liver Fibrosis via Mediating the Crosstalk between Liver Sinusoidal Endothelial Cells and Hepatic Stellate Cells. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2003721. [PMID: 34105268 PMCID: PMC8188197 DOI: 10.1002/advs.202003721] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 02/10/2021] [Indexed: 05/16/2023]
Abstract
Development of liver fibrosis results in drastic changes in the liver microenvironment, which in turn accelerates disease progression. Although the pathological function of various hepatic cells in fibrogenesis is identified, the crosstalk between them remains obscure. The present study demonstrates that hepatic expression of adipocyte fatty acid binding protein (A-FABP) is induced especially in the liver sinusoidal endothelial cells (LSECs) in mice after bile duct ligation (BDL). Genetic ablation and pharmacological inhibition of A-FABP attenuate BDL- or carbon tetrachloride-induced liver fibrosis in mice associating with reduced collagen accumulation, LSEC capillarization, and hepatic stellate cell (HSC) activation. Mechanistically, elevated A-FABP promotes LSEC capillarization by activating Hedgehog signaling, thus impairs the gatekeeper function of LSEC on HSC activation. LSEC-derived A-FABP also acts on HSCs in paracrine manner to potentiate the transactivation of transforming growth factor β1 (TGFβ1) by activating c-Jun N-terminal kinase (JNK)/c-Jun signaling. Elevated TGFβ1 subsequently exaggerates liver fibrosis. These findings uncover a novel pathological mechanism of liver fibrosis in which LSEC-derived A-FABP is a key regulator modulating the onset and progression of the disease. Targeting A-FABP may represent a potential approach against liver fibrosis.
Collapse
Affiliation(s)
- Xiaoping Wu
- State Key Laboratory of Pharmaceutical BiotechnologyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
- Department of Pharmacology and PharmacyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
| | - Lingling Shu
- State Key Laboratory of Pharmaceutical BiotechnologyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
- Department of MedicineLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
- State Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineSun Yat‐sen University Cancer CenterGuangzhou510060China
| | - Zixuan Zhang
- State Key Laboratory of Pharmaceutical BiotechnologyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
- Department of Pharmacology and PharmacyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
| | - Jingjing Li
- Department of Pharmacology and PharmacyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
| | - Jiuyu Zong
- State Key Laboratory of Pharmaceutical BiotechnologyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
- Department of Pharmacology and PharmacyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
| | - Lai Yee Cheong
- State Key Laboratory of Pharmaceutical BiotechnologyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
- Department of MedicineLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
| | - Dewei Ye
- Joint Laboratory of Guangdong and Hong Kong on Metabolic DiseasesGuangdong Pharmaceutical UniversityGuangzhou510000China
| | - Karen S. L. Lam
- State Key Laboratory of Pharmaceutical BiotechnologyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
- Department of MedicineLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
| | - Erfei Song
- Department of Metabolic and Bariatric SurgeryThe First Affiliated Hospital of Jinan UniversityGuangzhouGuangdong510630China
| | - Cunchuan Wang
- Department of Metabolic and Bariatric SurgeryThe First Affiliated Hospital of Jinan UniversityGuangzhouGuangdong510630China
| | - Aimin Xu
- State Key Laboratory of Pharmaceutical BiotechnologyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
- Department of Pharmacology and PharmacyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
- Department of MedicineLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
| | - Ruby L. C. Hoo
- State Key Laboratory of Pharmaceutical BiotechnologyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
- Department of Pharmacology and PharmacyLKS Faculty of Medicinethe University of Hong KongHong Kong999077China
- HKU‐Shenzhen Institute of Research and Innovation (HKU‐SIRI)Shenzhen518057China
| |
Collapse
|
7
|
Xu S, Zhang T, Cao Z, Zhong W, Zhang C, Li H, Song J. Integrin-α9β1 as a Novel Therapeutic Target for Refractory Diseases: Recent Progress and Insights. Front Immunol 2021; 12:638400. [PMID: 33790909 PMCID: PMC8005531 DOI: 10.3389/fimmu.2021.638400] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 02/26/2021] [Indexed: 12/12/2022] Open
Abstract
Integrins refer to heterodimers consisting of subunits α and β. They serve as receptors on cell membranes and interact with extracellular ligands to mediate intracellular molecular signals. One of the least-studied members of the integrin family is integrin-α9β1, which is widely distributed in various human tissues and organs. Integrin-α9β1 regulates the physiological state of cells through a variety of complex signaling pathways to participate in the specific pathological processes of some intractable diseases. In recent years, an increasing amount of research has focused on the role of α9β1 in the molecular mechanisms of different refractory diseases and its promising potential as a therapeutic target. Accordingly, this review introduces and summarizes recent research related to integrin-α9β1, describes the synergistic functions of α9β1 and its corresponding ligands in cancer, autoimmune diseases, nerve injury and thrombosis and, more importantly, highlights the potential of α9β1 as a distinctive target for the treatment of these intractable diseases.
Collapse
Affiliation(s)
- Shihan Xu
- College of Stomatology, Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China.,Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Tingwei Zhang
- College of Stomatology, Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China.,Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Zhengguo Cao
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China.,Department of Periodontology, School & Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Wenjie Zhong
- College of Stomatology, Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China.,Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Chuangwei Zhang
- College of Stomatology, Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China.,Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Han Li
- College of Stomatology, Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China.,Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Jinlin Song
- College of Stomatology, Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China.,Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| |
Collapse
|
8
|
Zhang L, Yan H, Tai Y, Xue Y, Wei Y, Wang K, Zhao Q, Wang S, Kong D, Midgley AC. Design and Evaluation of a Polypeptide that Mimics the Integrin Binding Site for EDA Fibronectin to Block Profibrotic Cell Activity. Int J Mol Sci 2021; 22:ijms22041575. [PMID: 33557232 PMCID: PMC7913925 DOI: 10.3390/ijms22041575] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/18/2021] [Accepted: 02/01/2021] [Indexed: 02/07/2023] Open
Abstract
Fibrosis is characterized by excessive production of disorganized collagen- and fibronectin-rich extracellular matrices (ECMs) and is driven by the persistence of myofibroblasts within tissues. A key protein contributing to myofibroblast differentiation is extra domain A fibronectin (EDA-FN). We sought to target and interfere with interactions between EDA-FN and its integrin receptors to effectively inhibit profibrotic activity and myofibroblast formation. Molecular docking was used to assist in the design of a blocking polypeptide (antifibrotic 38-amino-acid polypeptide, AF38Pep) for specific inhibition of EDA-FN associations with the fibroblast-expressed integrins α4β1 and α4β7. Blocking peptides were designed and evaluated in silico before synthesis, confirmation of binding specificity, and evaluation in vitro. We identified the high-affinity EDA-FN C-C′ loop binding cleft within integrins α4β1 and α4β7. The polypeptide with the highest predicted binding affinity, AF38Pep, was synthesized and could achieve specific binding to myofibroblast fibronectin-rich ECM and EDA-FN C-C′ loop peptides. AF38Pep demonstrated potent myofibroblast inhibitory activity at 10 µg/mL and was not cytotoxic. Treatment with AF38Pep prevented integrin α4β1-mediated focal adhesion kinase (FAK) activation and early signaling through extracellular-signal-regulated kinases 1 and 2 (ERK1/2), attenuated the expression of pro-matrix metalloproteinase 9 (MMP9) and pro-MMP2, and inhibited collagen synthesis and deposition. Immunocytochemistry staining revealed an inhibition of α-smooth muscle actin (α-SMA) incorporation into actin stress fibers and attenuated cell contraction. Increases in the expression of mRNA associated with fibrosis and downstream from integrin signaling were inhibited by treatment with AF38Pep. Our study suggested that AF38Pep could successfully interfere with EDA-FN C-C′ loop-specific integrin interactions and could act as an effective inhibitor of fibroblast of myofibroblast differentiation.
Collapse
Affiliation(s)
- Lin Zhang
- Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China; (L.Z.); (H.Y.); (Y.T.); (Y.X.); (Y.W.); (K.W.); (Q.Z.); (D.K.)
| | - Hongyu Yan
- Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China; (L.Z.); (H.Y.); (Y.T.); (Y.X.); (Y.W.); (K.W.); (Q.Z.); (D.K.)
| | - Yifan Tai
- Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China; (L.Z.); (H.Y.); (Y.T.); (Y.X.); (Y.W.); (K.W.); (Q.Z.); (D.K.)
| | - Yueming Xue
- Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China; (L.Z.); (H.Y.); (Y.T.); (Y.X.); (Y.W.); (K.W.); (Q.Z.); (D.K.)
| | - Yongzhen Wei
- Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China; (L.Z.); (H.Y.); (Y.T.); (Y.X.); (Y.W.); (K.W.); (Q.Z.); (D.K.)
| | - Kai Wang
- Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China; (L.Z.); (H.Y.); (Y.T.); (Y.X.); (Y.W.); (K.W.); (Q.Z.); (D.K.)
| | - Qiang Zhao
- Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China; (L.Z.); (H.Y.); (Y.T.); (Y.X.); (Y.W.); (K.W.); (Q.Z.); (D.K.)
| | - Shufang Wang
- Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China; (L.Z.); (H.Y.); (Y.T.); (Y.X.); (Y.W.); (K.W.); (Q.Z.); (D.K.)
- Correspondence: (S.W.); (A.C.M.); Tel.: +86-1562-004-7851 (A.C.M.)
| | - Deling Kong
- Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China; (L.Z.); (H.Y.); (Y.T.); (Y.X.); (Y.W.); (K.W.); (Q.Z.); (D.K.)
- Rongxiang Xu Center for Regenerative Life Science, State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Adam C. Midgley
- Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, China; (L.Z.); (H.Y.); (Y.T.); (Y.X.); (Y.W.); (K.W.); (Q.Z.); (D.K.)
- Rongxiang Xu Center for Regenerative Life Science, State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
- Correspondence: (S.W.); (A.C.M.); Tel.: +86-1562-004-7851 (A.C.M.)
| |
Collapse
|
9
|
FN-EDA mediates angiogenesis of hepatic fibrosis via integrin-VEGFR2 in a CD63 synergetic manner. Cell Death Discov 2020; 6:140. [PMID: 33293521 PMCID: PMC7722740 DOI: 10.1038/s41420-020-00378-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 10/29/2020] [Accepted: 11/13/2020] [Indexed: 01/13/2023] Open
Abstract
Pathological angiogenesis is an important component of hepatic fibrosis along with fibrous deposition, but its role is not well understood. Here, we demonstrated that fibronectin containing extra domain A(FN-EDA), a fibronectin splice variant highly expressed in hepatic fibrosis, mediated angiogenesis in disease progression. FN-EDA was positively correlated with pathological angiogenesis in hepatic fibrosis, and a reduction in FN-EDA expression was associated with diminished intrahepatic angiogenesis and fibrosis. FN-EDA mostly colocalized with hepatic stellate cells (HSCs) and interference or blockage of FN-EDA attenuated migration and tube formation in co-cultured endothelial cells. Mechanistic studies indicated that FN-EDA was secreted to promote phosphorylation of VEGFR2 with the assistance of integrin and CD63. Targeting FN-EDA-integrin combination postponed the progression of hepatic angiogenesis and fibrosis in vivo. These results indicated that FN-EDA plays an emerging role in angiogenesis in hepatic fibrosis and could be a potential therapeutic intervention for the disease.
Collapse
|
10
|
Jalan-Sakrikar N, De Assuncao TM, Shi G, Aseem S, Chi C, Shah VH, Huebert RC. Proteasomal Degradation of Enhancer of Zeste Homologue 2 in Cholangiocytes Promotes Biliary Fibrosis. Hepatology 2019; 70:1674-1689. [PMID: 31070797 PMCID: PMC6819212 DOI: 10.1002/hep.30706] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 05/03/2019] [Indexed: 12/13/2022]
Abstract
During biliary disease, cholangiocytes become activated by various pathological stimuli, including transforming growth factor β (TGF-β). The result is an epigenetically regulated transcriptional program leading to a pro-fibrogenic microenvironment, activation of hepatic stellate cells (HSCs), and progression of biliary fibrosis. This study evaluated how TGF-β signaling intersects with epigenetic machinery in cholangiocytes to support fibrogenic gene transcription. We performed RNA sequencing in cholangiocytes with or without TGF-β. Ingenuity pathway analysis identified "HSC Activation" as the highly up-regulated pathway, including overexpression of fibronectin 1 (FN), connective tissue growth factor, and other genes. Bioinformatics identified enhancer of zeste homologue 2 (EZH2) as an epigenetic regulator of the cholangiocyte TGF-β response. EZH2 overexpression suppressed TGF-β-induced FN protein in vitro, suggesting FN as a direct target of EZH2-based repression. Chromatin immunoprecipitation assays identified an FN promoter element in which EZH2-mediated tri-methylation of lysine 27 on histone 3 is diminished by TGF-β. TGF-β also caused a 50% reduction in EZH2 protein levels. Proteasome inhibition rescued EZH2 protein and led to reduced FN production. Immunoprecipitation followed by mass spectrometry identified ubiquitin protein ligase E3 component N-recognin 4 in complex with EZH2, which was validated by western blotting in vitro. Ubiquitin mutation studies suggested K63-based ubiquitin linkage and chain elongation on EZH2 in response to TGF-β. A deletion mutant of EZH2, lacking its N-terminal domain, abrogates both TGF-β-stimulated EZH2 degradation and FN release. In vivo, cholangiocyte-selective knockout of EZH2 exacerbates bile duct ligation-induced fibrosis whereas MDR2-/- mice are protected from fibrosis by the proteasome inhibitor bortezomib. Conclusion: TGF-β regulates proteasomal degradation of EZH2 through N-terminal, K63-linked ubiquitination in cholangiocytes and activates transcription of a fibrogenic gene program that supports biliary fibrosis.
Collapse
Affiliation(s)
- Nidhi Jalan-Sakrikar
- Division of Gastroenterology and Hepatology, Mayo Clinic and Foundation, Rochester, MN.,Gastroenterology Research Unit, Mayo Clinic and Foundation, Rochester, MN
| | - Thiago M. De Assuncao
- Division of Gastroenterology and Hepatology, Mayo Clinic and Foundation, Rochester, MN.,Gastroenterology Research Unit, Mayo Clinic and Foundation, Rochester, MN
| | - Guang Shi
- Division of Gastroenterology and Hepatology, Mayo Clinic and Foundation, Rochester, MN.,Gastroenterology Research Unit, Mayo Clinic and Foundation, Rochester, MN
| | - SayedObaidullah Aseem
- Division of Gastroenterology and Hepatology, Mayo Clinic and Foundation, Rochester, MN.,Gastroenterology Research Unit, Mayo Clinic and Foundation, Rochester, MN
| | - Cheng Chi
- Division of Gastroenterology and Hepatology, Mayo Clinic and Foundation, Rochester, MN.,Gastroenterology Research Unit, Mayo Clinic and Foundation, Rochester, MN
| | - Vijay H. Shah
- Division of Gastroenterology and Hepatology, Mayo Clinic and Foundation, Rochester, MN.,Gastroenterology Research Unit, Mayo Clinic and Foundation, Rochester, MN.,Center for Cell Signaling in Gastroenterology; Mayo Clinic and Foundation, Rochester, MN
| | - Robert C. Huebert
- Division of Gastroenterology and Hepatology, Mayo Clinic and Foundation, Rochester, MN.,Gastroenterology Research Unit, Mayo Clinic and Foundation, Rochester, MN.,Center for Cell Signaling in Gastroenterology; Mayo Clinic and Foundation, Rochester, MN
| |
Collapse
|
11
|
Zent J, Guo LW. Signaling Mechanisms of Myofibroblastic Activation: Outside-in and Inside-Out. Cell Physiol Biochem 2018; 49:848-868. [PMID: 30184544 DOI: 10.1159/000493217] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Accepted: 08/27/2018] [Indexed: 12/17/2022] Open
Abstract
Myofibroblasts are central mediators of fibrosis. Typically derived from resident fibroblasts, myofibroblasts represent a heterogeneous population of cells that are principally defined by acquired contractile function and high synthetic ability to produce extracellular matrix (ECM). Current literature sheds new light on the critical role of ECM signaling coupled with mechanotransduction in driving myofibroblastic activation. In particular, transforming growth factor β1 (TGF-β1) and extra domain A containing fibronectin (EDA-FN) are thought to be the primary ECM signaling mediators that form and also induce positive feedback loops. The outside-in and inside-out signaling circuits are transmitted and integrated by TGF-β receptors and integrins at the cell membrane, ultimately perpetuating the abundance and activities of TGF-β1 and EDA-FN in the ECM. In this review, we highlight these conceptual advances in understanding myofibroblastic activation, in hope of revealing its therapeutic anti-fibrotic implications.
Collapse
Affiliation(s)
- Joshua Zent
- Medical Scientist Training Program, the Ohio State University, Columbus, Columbus, Ohio, USA
| | - Lian-Wang Guo
- Department of Surgery, Department of Physiology & Cell Biology, College of Medicine, Davis Heart and Lung Research Institute, Wexner Medical Center, the Ohio State University, Columbus, Ohio, USA
| |
Collapse
|
12
|
Klingberg F, Chau G, Walraven M, Boo S, Koehler A, Chow ML, Olsen AL, Im M, Lodyga M, Wells RG, White ES, Hinz B. The fibronectin ED-A domain enhances recruitment of latent TGF-β-binding protein-1 to the fibroblast matrix. J Cell Sci 2018; 131:jcs201293. [PMID: 29361522 PMCID: PMC5897715 DOI: 10.1242/jcs.201293] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 01/09/2018] [Indexed: 12/18/2022] Open
Abstract
Dysregulated secretion and extracellular activation of TGF-β1 stimulates myofibroblasts to accumulate disordered and stiff extracellular matrix (ECM) leading to fibrosis. Fibronectin immobilizes latent TGF-β-binding protein-1 (LTBP-1) and thus stores TGF-β1 in the ECM. Because the ED-A fibronectin splice variant is prominently expressed during fibrosis and supports myofibroblast activation, we investigated whether ED-A promotes LTBP-1-fibronectin interactions. Using stiffness-tuneable substrates for human dermal fibroblast cultures, we showed that high ECM stiffness promotes expression and colocalization of LTBP-1 and ED-A-containing fibronectin. When rescuing fibronectin-depleted fibroblasts with specific fibronectin splice variants, LTBP-1 bound more efficiently to ED-A-containing fibronectin than to ED-B-containing fibronectin and fibronectin lacking splice domains. Function blocking of the ED-A domain using antibodies and competitive peptides resulted in reduced LTBP-1 binding to ED-A-containing fibronectin, reduced LTBP-1 incorporation into the fibroblast ECM and reduced TGF-β1 activation. Similar results were obtained by blocking the heparin-binding stretch FNIII12-13-14 (HepII), adjacent to the ED-A domain in fibronectin. Collectively, our results suggest that the ED-A domain enhances association of the latent TGF-β1 by promoting weak direct binding to LTBP-1 and by enhancing heparin-mediated protein interactions through HepII in fibronectin.
Collapse
Affiliation(s)
- Franco Klingberg
- Laboratory of Tissue Repair and Regeneration, Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, 150 College St., FG234, ON M5S3E2, Canada
| | - Grace Chau
- Laboratory of Tissue Repair and Regeneration, Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, 150 College St., FG234, ON M5S3E2, Canada
| | - Marielle Walraven
- Laboratory of Tissue Repair and Regeneration, Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, 150 College St., FG234, ON M5S3E2, Canada
| | - Stellar Boo
- Laboratory of Tissue Repair and Regeneration, Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, 150 College St., FG234, ON M5S3E2, Canada
| | - Anne Koehler
- Laboratory of Tissue Repair and Regeneration, Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, 150 College St., FG234, ON M5S3E2, Canada
| | - Melissa L Chow
- Laboratory of Tissue Repair and Regeneration, Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, 150 College St., FG234, ON M5S3E2, Canada
| | - Abby L Olsen
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, 421 Curie Blvd., BRB, Philadelphia, PA 19104, USA
| | - Michelle Im
- Laboratory of Tissue Repair and Regeneration, Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, 150 College St., FG234, ON M5S3E2, Canada
| | - Monika Lodyga
- Laboratory of Tissue Repair and Regeneration, Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, 150 College St., FG234, ON M5S3E2, Canada
| | - Rebecca G Wells
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, 421 Curie Blvd., BRB, Philadelphia, PA 19104, USA
| | - Eric S White
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Michigan, 1500 E. Medical Center Drive, Ann Arbor, MI 48109, USA
| | - Boris Hinz
- Laboratory of Tissue Repair and Regeneration, Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, 150 College St., FG234, ON M5S3E2, Canada
| |
Collapse
|
13
|
Abstract
Portal hypertension develops as a result of increased intrahepatic vascular resistance often caused by chronic liver disease that leads to structural distortion by fibrosis, microvascular thrombosis, dysfunction of liver sinusoidal endothelial cells (LSECs), and hepatic stellate cell (HSC) activation. While the basic mechanisms of LSEC and HSC dysregulation have been extensively studied, the role of microvascular thrombosis and platelet function in the pathogenesis of portal hypertension remains to be clearly characterized. As a secondary event, portal hypertension results in splanchnic and systemic arterial vasodilation, leading to the development of a hyperdynamic circulatory syndrome and subsequently to clinically devastating complications including gastroesophageal varices and variceal hemorrhage, hepatic encephalopathy from the formation of portosystemic shunts, ascites, and renal failure due to the hepatorenal syndrome. This review article discusses: (1) mechanisms of sinusoidal portal hypertension, focusing on HSC and LSEC biology, pathological angiogenesis, and the role of microvascular thrombosis and platelets, (2) the mesenteric vasculature in portal hypertension, and (3) future directions for vascular biology research in portal hypertension.
Collapse
Affiliation(s)
- Matthew McConnell
- Department of Internal Medicine, Section of Digestive Diseases, Yale University School of Medicine, 1080 LMP, 333 Cedar St., New Haven, CT, 06520, USA
| | - Yasuko Iwakiri
- Department of Internal Medicine, Section of Digestive Diseases, Yale University School of Medicine, 1080 LMP, 333 Cedar St., New Haven, CT, 06520, USA.
| |
Collapse
|
14
|
Abstract
This update focuses on two main topics. First, recent developments in our understanding of liver sinusoidal endothelial cell (LSEC) function will be reviewed, specifically elimination of blood-borne waste, immunological function of LSECs, interaction of LSECs with liver metastases, LSECs and liver regeneration, and LSECs and hepatic fibrosis. Second, given the current emphasis on rigor and transparency in biomedical research, the update discusses the need for standardization of methods to demonstrate identity and purity of isolated LSECs, pitfalls in methods that might lead to a selection bias in the types of LSECs isolated, and questions about long-term culture of LSECs. Various surface markers used for immunomagnetic selection are reviewed.
Collapse
Affiliation(s)
- Laurie D. DeLeve
- Division of Gastrointestinal and Liver Diseases and the USC Research Center for Liver Diseases, Keck School of Medicine of the University of Southern California, Los Angeles, California
| | - Ana C. Maretti-Mira
- Division of Gastrointestinal and Liver Diseases and the USC Research Center for Liver Diseases, Keck School of Medicine of the University of Southern California, Los Angeles, California
| |
Collapse
|
15
|
Mazza G, Al-Akkad W, Rombouts K. Engineering in vitro models of hepatofibrogenesis. Adv Drug Deliv Rev 2017; 121:147-157. [PMID: 28578016 DOI: 10.1016/j.addr.2017.05.018] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 05/17/2017] [Accepted: 05/26/2017] [Indexed: 02/07/2023]
Abstract
Chronic liver disease is a major cause of morbidity and mortality worldwide marked by chronic inflammation and fibrosis/scarring, resulting in end-stage liver disease and its complications. Hepatic stellate cells (HSCs) are a dominant contributor to liver fibrosis by producing excessive extracellular matrix (ECM), irrespective of the underlying disease aetiologies, and for many decades research has focused on the development of a number of anti-fibrotic strategies targeting this cell. Despite major improvements in two-dimensional systems (2D) by using a variety of cell culture models of different complexity, an efficient anti-fibrogenic therapy has yet to be developed. The development of well-defined three-dimensional (3D) in vitro models, which mimic ECM structures as found in vivo, have demonstrated the importance of cell-matrix bio-mechanics, the complex interactions between HSCs and hepatocytes and other non-parenchymal cells, and this to improve and promote liver cell-specific functions. Henceforth, refinement of these 3D in vitro models, which reproduce the liver microenvironment, will lead to new objectives and to a possible new era in the search for antifibrogenic compounds.
Collapse
|
16
|
Kulkarni T, O'Reilly P, Antony VB, Gaggar A, Thannickal VJ. Matrix Remodeling in Pulmonary Fibrosis and Emphysema. Am J Respir Cell Mol Biol 2017; 54:751-60. [PMID: 26741177 DOI: 10.1165/rcmb.2015-0166ps] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Pulmonary fibrosis and emphysema are chronic lung diseases characterized by a progressive decline in lung function, resulting in significant morbidity and mortality. A hallmark of these diseases is recurrent or persistent alveolar epithelial injury, typically caused by common environmental exposures such as cigarette smoke. We propose that critical determinants of the outcome of the injury-repair processes that result in fibrosis versus emphysema are mesenchymal cell fate and associated extracellular matrix dynamics. In this review, we explore the concept that regulation of mesenchymal cells under the influence of soluble factors, in particular transforming growth factor-β1, and the extracellular matrix determine the divergent tissue remodeling responses seen in pulmonary fibrosis and emphysema.
Collapse
Affiliation(s)
- Tejaswini Kulkarni
- 1 Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama.,2 Program in Protease and Matrix Biology Center, Birmingham, Alabama; and
| | - Philip O'Reilly
- 1 Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama.,2 Program in Protease and Matrix Biology Center, Birmingham, Alabama; and
| | - Veena B Antony
- 1 Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama.,2 Program in Protease and Matrix Biology Center, Birmingham, Alabama; and
| | - Amit Gaggar
- 1 Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama.,2 Program in Protease and Matrix Biology Center, Birmingham, Alabama; and.,3 Birmingham VA Medical Center, Birmingham, Alabama
| | - Victor J Thannickal
- 1 Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama.,2 Program in Protease and Matrix Biology Center, Birmingham, Alabama; and.,3 Birmingham VA Medical Center, Birmingham, Alabama
| |
Collapse
|
17
|
Sackey-Aboagye B, Olsen AL, Mukherjee SM, Ventriglia A, Yokosaki Y, Greenbaum LE, Lee GY, Naga H, Wells RG. Fibronectin Extra Domain A Promotes Liver Sinusoid Repair following Hepatectomy. PLoS One 2016; 11:e0163737. [PMID: 27741254 PMCID: PMC5065221 DOI: 10.1371/journal.pone.0163737] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 09/13/2016] [Indexed: 11/19/2022] Open
Abstract
Liver sinusoidal endothelial cells (LSECs) are the main endothelial cells in the liver and are important for maintaining liver homeostasis as well as responding to injury. LSECs express cellular fibronectin containing the alternatively spliced extra domain A (EIIIA-cFN) and increase expression of this isoform after liver injury, although its function is not well understood. Here, we examined the role of EIIIA-cFN in liver regeneration following partial hepatectomy. We carried out two-thirds partial hepatectomies in mice lacking EIIIA-cFN and in their wild type littermates, studied liver endothelial cell adhesion on decellularized, EIIIA-cFN-containing matrices and investigated the role of cellular fibronectins in liver endothelial cell tubulogenesis. We found that liver weight recovery following hepatectomy was significantly delayed and that sinusoidal repair was impaired in EIIIA-cFN null mice, especially females, as was the lipid accumulation typical of the post-hepatectomy liver. In vitro, we found that liver endothelial cells were more adhesive to cell-deposited matrices containing the EIIIA domain and that cellular fibronectin enhanced tubulogenesis and vascular cord formation. The integrin α9β1, which specifically binds EIIIA-cFN, promoted tubulogenesis and adhesion of liver endothelial cells to EIIIA-cFN. Our findings identify a role for EIIIA-cFN in liver regeneration and tubulogenesis. We suggest that sinusoidal repair is enhanced by increased LSEC adhesion, which is mediated by EIIIA-cFN.
Collapse
Affiliation(s)
- Bridget Sackey-Aboagye
- Department of Medicine, Perelman School of Medicine, The University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, The University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Abby L. Olsen
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, The University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Sarmistha M. Mukherjee
- Department of Physiology, Perelman School of Medicine, The University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Alexander Ventriglia
- Department of Bioengineering, School of Engineering and Applied Sciences, The University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | | | | | - Gi Yun Lee
- Department of Bioengineering, School of Engineering and Applied Sciences, The University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Hani Naga
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Rebecca G. Wells
- Department of Medicine, Perelman School of Medicine, The University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, The University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- * E-mail:
| |
Collapse
|
18
|
Hymes JP, Klaenhammer TR. Stuck in the Middle: Fibronectin-Binding Proteins in Gram-Positive Bacteria. Front Microbiol 2016; 7:1504. [PMID: 27713740 PMCID: PMC5031765 DOI: 10.3389/fmicb.2016.01504] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 09/08/2016] [Indexed: 11/13/2022] Open
Abstract
Fibronectin is a multidomain glycoprotein found ubiquitously in human body fluids and extracellular matrices of a variety of cell types from all human tissues and organs, including intestinal epithelial cells. Fibronectin plays a major role in the regulation of cell migration, tissue repair, and cell adhesion. Importantly, fibronectin also serves as a common target for bacterial adhesins in the gastrointestinal tract. Fibronectin-binding proteins (FnBPs) have been identified and characterized in a wide variety of host-associated bacteria. Single bacterial species can contain multiple, diverse FnBPs. In pathogens, some FnBPs contribute to virulence via host cell attachment, invasion, and interference with signaling pathways. Although FnBPs in commensal and probiotic strains are not sufficient to confer virulence, they are essential for attachment to their ecological niches. Here we describe the interaction between human fibronectin and bacterial adhesins by highlighting the FnBPs of Gram-positive pathogens and commensals. We provide an overview of the occurrence and diversity of FnBPs with a focus on the model pathogenic organisms in which FnBPs are most characterized. Continued investigation of FnBPs is needed to fully understand their divergence and specificity in both pathogens and commensals.
Collapse
Affiliation(s)
- Jeffrey P Hymes
- Department of Food, Bioprocessing, and Nutrition Sciences, North Carolina State University Raleigh, NC, USA
| | - Todd R Klaenhammer
- Department of Food, Bioprocessing, and Nutrition Sciences, North Carolina State University Raleigh, NC, USA
| |
Collapse
|
19
|
Identification and characterization of a unique role for EDB fibronectin in phagocytosis. J Mol Med (Berl) 2015; 94:567-81. [PMID: 26637426 PMCID: PMC4856727 DOI: 10.1007/s00109-015-1373-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 11/12/2015] [Accepted: 11/19/2015] [Indexed: 01/21/2023]
Abstract
Abstract Plasma fibronectin is a circulating protein that facilitates phagocytosis by connecting bacteria to immune cells. A fibronectin isoform, which includes a sequence of 90 AA called extra-domain B (EDB), is synthesized de novo at the messenger RNA (mRNA) level in immune cells, but the reason for its expression remains elusive. We detected an 80-fold increase in EDB-containing fibronectin in the cerebrospinal fluid of patients with bacterial meningitis that was most pronounced in staphylococcal infections. A role for this isoform in phagocytosis was further suggested by enhanced EDB fibronectin release after internalization of Staphylococcus aureus in vitro. Using transgenic mouse models, we established that immune cell production of fibronectin contributes to phagocytosis, more so than circulating plasma fibronectin, and that accentuated release of EDB-containing fibronectin by immune cells improved phagocytosis. In line with this, administration of EDB fibronectin enhanced in vitro phagocytosis to a larger extent than plasma fibronectin. This enhancement was mediated by αvβ3 integrin as shown using inhibitors or cells from β3 integrin knockout mice. Thus, we identified both a novel function for EDB fibronectin in augmenting phagocytosis over circulating plasma fibronectin, as well as the mediating receptor. Our data also establish for the first time, a direct role for β3 integrin in bacterial phagocytosis in mammals. Key messages • Fibronectin containing an extra domain called EDB is released in bacterial meningitis. • EDB-containing fibronectin enhances phagocytosis more than plasma fibronectin. • The enhancement is mediated by activation of αvβ3 integrin in the presence of EDB. Electronic supplementary material The online version of this article (doi:10.1007/s00109-015-1373-0) contains supplementary material, which is available to authorized users.
Collapse
|
20
|
Iwasaki A, Sakai K, Moriya K, Sasaki T, Keene DR, Akhtar R, Miyazono T, Yasumura S, Watanabe M, Morishita S, Sakai T. Molecular Mechanism Responsible for Fibronectin-controlled Alterations in Matrix Stiffness in Advanced Chronic Liver Fibrogenesis. J Biol Chem 2015; 291:72-88. [PMID: 26553870 DOI: 10.1074/jbc.m115.691519] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Indexed: 12/23/2022] Open
Abstract
Fibrosis is characterized by extracellular matrix (ECM) remodeling and stiffening. However, the functional contribution of tissue stiffening to noncancer pathogenesis remains largely unknown. Fibronectin (Fn) is an ECM glycoprotein substantially expressed during tissue repair. Here we show in advanced chronic liver fibrogenesis using a mouse model lacking Fn that, unexpectedly, Fn-null livers lead to more extensive liver cirrhosis, which is accompanied by increased liver matrix stiffness and deteriorated hepatic functions. Furthermore, Fn-null livers exhibit more myofibroblast phenotypes and accumulate highly disorganized/diffuse collagenous ECM networks composed of thinner and significantly increased number of collagen fibrils during advanced chronic liver damage. Mechanistically, mutant livers show elevated local TGF-β activity and lysyl oxidase expressions. A significant amount of active lysyl oxidase is released in Fn-null hepatic stellate cells in response to TGF-β1 through canonical and noncanonical Smad such as PI3 kinase-mediated pathways. TGF-β1-induced collagen fibril stiffness in Fn-null hepatic stellate cells is significantly higher compared with wild-type cells. Inhibition of lysyl oxidase significantly reduces collagen fibril stiffness, and treatment of Fn recovers collagen fibril stiffness to wild-type levels. Thus, our findings indicate an indispensable role for Fn in chronic liver fibrosis/cirrhosis in negatively regulating TGF-β bioavailability, which in turn modulates ECM remodeling and stiffening and consequently preserves adult organ functions. Furthermore, this regulatory mechanism by Fn could be translated for a potential therapeutic target in a broader variety of chronic fibrotic diseases.
Collapse
Affiliation(s)
- Ayumi Iwasaki
- From the MRC Centre for Drug Safety Science, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3GE, United Kingdom, the Graduate School of Biomedical Engineering and
| | - Keiko Sakai
- From the MRC Centre for Drug Safety Science, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3GE, United Kingdom, the Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195
| | - Kei Moriya
- the Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195
| | - Takako Sasaki
- the Department of Biochemistry, Faculty of Medicine, Oita University, Oita, 879-5593, Japan
| | - Douglas R Keene
- the Micro-Imaging Center, Shriners Hospital for Children, Portland, Oregon 97231
| | - Riaz Akhtar
- Centre for Materials and Structures, School of Engineering, University of Liverpool, Liverpool L69 3GH, United Kingdom
| | - Takayoshi Miyazono
- Department of Gastroenterology and Hepatology, and Transfusion Medicine and Cell Therapy, Toyama University, Toyama 930-0194, Japan, and
| | - Satoshi Yasumura
- Department of Gastroenterology and Hepatology, and Transfusion Medicine and Cell Therapy, Toyama University, Toyama 930-0194, Japan, and
| | | | - Shin Morishita
- Environmental and Information Science, Yokohama National University, Yokohama 240-8501, Japan
| | - Takao Sakai
- From the MRC Centre for Drug Safety Science, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3GE, United Kingdom, the Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195,
| |
Collapse
|
21
|
DeLeve LD. Liver sinusoidal endothelial cells in hepatic fibrosis. Hepatology 2015; 61:1740-6. [PMID: 25131509 PMCID: PMC4333127 DOI: 10.1002/hep.27376] [Citation(s) in RCA: 306] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 08/13/2014] [Indexed: 02/06/2023]
Abstract
Capillarization, lack of liver sinusoidal endothelial cell (LSEC) fenestration, and formation of an organized basement membrane not only precedes fibrosis, but is also permissive for hepatic stellate cell activation and fibrosis. Thus, dysregulation of the LSEC phenotype is a critical step in the fibrotic process. Both a vascular endothelial growth factor (VEGF)-stimulated, nitric oxide (NO)-independent pathway and a VEGF-stimulated NO-dependent pathway are necessary to maintain the differentiated LSEC phenotype. The NO-dependent pathway is impaired in capillarization and activation of this pathway downstream from NO restores LSEC differentiation in vivo. Restoration of LSEC differentiation in vivo promotes HSC quiescence, enhances regression of fibrosis, and prevents progression of cirrhosis.
Collapse
Affiliation(s)
- Laurie D. DeLeve
- Division of Gastrointestinal and Liver Disease and the USC Research Center for Liver Diseases, Keck Medicine of the University of Southern California, Los Angeles CA
| |
Collapse
|
22
|
Abstract
Hepatic stellate cells are resident perisinusoidal cells distributed throughout the liver, with a remarkable range of functions in normal and injured liver. Derived embryologically from septum transversum mesenchyme, their precursors include submesothelial cells that invade the liver parenchyma from the hepatic capsule. In normal adult liver, their most characteristic feature is the presence of cytoplasmic perinuclear droplets that are laden with retinyl (vitamin A) esters. Normal stellate cells display several patterns of intermediate filaments expression (e.g., desmin, vimentin, and/or glial fibrillary acidic protein) suggesting that there are subpopulations within this parental cell type. In the normal liver, stellate cells participate in retinoid storage, vasoregulation through endothelial cell interactions, extracellular matrix homeostasis, drug detoxification, immunotolerance, and possibly the preservation of hepatocyte mass through secretion of mitogens including hepatocyte growth factor. During liver injury, stellate cells activate into alpha smooth muscle actin-expressing contractile myofibroblasts, which contribute to vascular distortion and increased vascular resistance, thereby promoting portal hypertension. Other features of stellate cell activation include mitogen-mediated proliferation, increased fibrogenesis driven by connective tissue growth factor, and transforming growth factor beta 1, amplified inflammation and immunoregulation, and altered matrix degradation. Evolving areas of interest in stellate cell biology seek to understand mechanisms of their clearance during fibrosis resolution by either apoptosis, senescence, or reversion, and their contribution to hepatic stem cell amplification, regeneration, and hepatocellular cancer.
Collapse
Affiliation(s)
- Juan E Puche
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai Hospital, New York, New York, New York
| | | | | |
Collapse
|
23
|
Stoffels JMJ, Hoekstra D, Franklin RJM, Baron W, Zhao C. The EIIIA domain from astrocyte-derived fibronectin mediates proliferation of oligodendrocyte progenitor cells following CNS demyelination. Glia 2014; 63:242-56. [PMID: 25156142 PMCID: PMC4737254 DOI: 10.1002/glia.22748] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 08/11/2014] [Indexed: 11/27/2022]
Abstract
Central nervous system remyelination by oligodendrocyte progenitor cells (OPCs) ultimately fails in the majority of multiple sclerosis (MS) lesions. Remyelination benefits from transient expression of factors that promote migration and proliferation of OPCs, which may include fibronectin (Fn). Fn is present in demyelinated lesions in two major forms; plasma Fn (pFn), deposited following blood‐brain barrier disruption, and cellular Fn, synthesized by resident glial cells and containing alternatively spliced domains EIIIA and EIIIB. Here, we investigated the distinctive roles that astrocyte‐derived Fn (aFn) and pFn play in remyelination. We used an inducible Cre‐lox recombination strategy to selectively remove pFn, aFn or both from mice, and examined the impact on remyelination of toxin‐induced demyelinated lesions of spinal cord white matter. This approach revealed that astrocytes are a major source of Fn in demyelinated lesions. Furthermore, following aFn conditional knockout, the number of OPCs recruited to the demyelinated lesion decreased significantly, whereas OPC numbers were unaltered following pFn conditional knockout. However, remyelination completed normally following conditional knockout of aFn and pFn. Both the EIIIA and EIIIB domains of aFn were expressed following demyelination, and in vitro assays demonstrated that the EIIIA domain of aFn mediates proliferation of OPCs, but not migration. Therefore, although the EIIIA domain from aFn mediates OPC proliferation, aFn is not essential for successful remyelination. Since previous findings indicated that astrocyte‐derived Fn aggregates in chronic MS lesions inhibit remyelination, aFn removal may benefit therapeutic strategies to promote remyelination in MS. GLIA 2015;63:242–256 We investigated the roles of cellular and plasma fibronectin in remyelination, and found that astrocyte‐derived fibronectin mediates oligodendrocyte progenitor cell proliferation in a toxin‐induced demyelination model, likely via the EIIIA domain.
Collapse
Affiliation(s)
- Josephine M J Stoffels
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, The Netherlands
| | | | | | | | | |
Collapse
|
24
|
Elpek G&O. Cellular and molecular mechanisms in the pathogenesis of liver fibrosis: An update. World J Gastroenterol 2014; 20:7260-7276. [PMID: 24966597 PMCID: PMC4064072 DOI: 10.3748/wjg.v20.i23.7260] [Citation(s) in RCA: 251] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2013] [Revised: 02/08/2014] [Accepted: 05/26/2014] [Indexed: 02/06/2023] Open
Abstract
There have been considerable recent advances towards a better understanding of the complex cellular and molecular network underlying liver fibrogenesis. Recent data indicate that the termination of fibrogenic processes and the restoration of deficient fibrolytic pathways may allow the reversal of advanced fibrosis and even cirrhosis. Therefore, efforts have been made to better clarify the cellular and molecular mechanisms that are involved in liver fibrosis. Activation of hepatic stellate cells (HSCs) remains a central event in fibrosis, complemented by other sources of matrix-producing cells, including portal fibroblasts, fibrocytes and bone marrow-derived myofibroblasts. These cells converge in a complex interaction with neighboring cells to provoke scarring in response to persistent injury. Defining the interaction of different cell types, revealing the effects of cytokines on these cells and characterizing the regulatory mechanisms that control gene expression in activated HSCs will enable the discovery of new therapeutic targets. Moreover, the characterization of different pathways associated with different etiologies aid in the development of disease-specific therapies. This article outlines recent advances regarding the cellular and molecular mechanisms involved in liver fibrosis that may be translated into future therapies. The pathogenesis of liver fibrosis associated with alcoholic liver disease, non-alcoholic fatty liver disease and viral hepatitis are also discussed to emphasize the various mechanisms involved in liver fibrosis.
Collapse
|
25
|
Murphy PA, Hynes RO. Alternative splicing of endothelial fibronectin is induced by disturbed hemodynamics and protects against hemorrhage of the vessel wall. Arterioscler Thromb Vasc Biol 2014; 34:2042-50. [PMID: 24903094 PMCID: PMC4140979 DOI: 10.1161/atvbaha.114.303879] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Abnormally low-flow conditions, sensed by the arterial endothelium, promote aneurysm rupture. Fibronectin (FN) is among the most abundant extracellular matrix proteins and is strongly upregulated in human aneurysms, suggesting a possible role in disease progression. Altered FN splicing can result in the inclusion of EIIIA and EIIIB exons, generally not expressed in adult tissues. We sought to explore the regulation of FN and its splicing and their possible roles in the vascular response to disturbed flow. APPROACH AND RESULTS We induced low and reversing flow in mice by partial carotid ligation and assayed FN splicing in an endothelium-enriched intimal preparation. Inclusion of EIIIA and EIIIB was increased as early as 48 hours, with negligible increases in total FN expression. To test the function of EIIIA and EIIIB inclusion, we induced disturbed flow in EIIIAB(-/-) mice unable to include these exons and found that they developed focal lesions with hemorrhage and hypertrophy of the vessel wall. Acute deletion of floxed FN caused similar defects in response to disturbed flow, consistent with a requirement for the upregulation of the spliced isoforms, rather than a developmental defect. Recruited macrophages promote FN splicing because their depletion by clodronate liposomes blocked the increase in endothelial EIIIA and EIIIB inclusion in the carotid model. CONCLUSIONS These results uncover a protective mechanism in the inflamed intima that develops under disturbed flow, by showing that splicing of FN mRNA in the endothelium, induced by macrophages, inhibits hemorrhage of the vessel wall.
Collapse
Affiliation(s)
- Patrick A Murphy
- From the Howard Hughes Medical Institute, David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA
| | - Richard O Hynes
- From the Howard Hughes Medical Institute, David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA.
| |
Collapse
|
26
|
Matrix biology of idiopathic pulmonary fibrosis: a workshop report of the national heart, lung, and blood institute. THE AMERICAN JOURNAL OF PATHOLOGY 2014; 184:1643-51. [PMID: 24726499 DOI: 10.1016/j.ajpath.2014.02.003] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 02/12/2014] [Accepted: 02/18/2014] [Indexed: 01/17/2023]
Abstract
A hallmark of idiopathic pulmonary fibrosis (IPF) is excessive and disordered deposition of extracellular matrix. Although the lung extracellular matrix normally plays an essential role in development and maintenance of lung tissue through reciprocal interactions with resident cells, the disordered matrix in the diseased lung is increasingly recognized as an active and important contributor to IPF pathogenesis. This working group summary from a recently conducted National Heart, Lung, and Blood Institute strategic planning workshop for IPF research highlights recent advances, challenges, and opportunities in the study of matrix biology in IPF. Particular attention is given to the composition and mechanical properties of the matrix in normal and diseased lungs, and the biochemical and biomechanical influences exerted by pathological matrix. Recently developed model systems are also summarized as key tools for advancing our understanding of matrix biology in IPF. Emerging approaches to therapeutically target the matrix in preclinical and clinical settings are discussed, as are important concepts, such as alterations of the matrix with aging and the potential for the resolution of fibrosis. Specific recommendations for future studies in matrix biology of IPF are also proposed.
Collapse
|
27
|
Blackwell TS, Tager AM, Borok Z, Moore BB, Schwartz DA, Anstrom KJ, Bar-Joseph Z, Bitterman P, Blackburn MR, Bradford W, Brown KK, Chapman HA, Collard HR, Cosgrove GP, Deterding R, Doyle R, Flaherty KR, Garcia CK, Hagood JS, Henke CA, Herzog E, Hogaboam CM, Horowitz JC, King TE, Loyd JE, Lawson WE, Marsh CB, Noble PW, Noth I, Sheppard D, Olsson J, Ortiz LA, O'Riordan TG, Oury TD, Raghu G, Roman J, Sime PJ, Sisson TH, Tschumperlin D, Violette SM, Weaver TE, Wells RG, White ES, Kaminski N, Martinez FJ, Wynn TA, Thannickal VJ, Eu JP. Future directions in idiopathic pulmonary fibrosis research. An NHLBI workshop report. Am J Respir Crit Care Med 2014; 189:214-22. [PMID: 24160862 DOI: 10.1164/rccm.201306-1141ws] [Citation(s) in RCA: 179] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The median survival of patients with idiopathic pulmonary fibrosis (IPF) continues to be approximately 3 years from the time of diagnosis, underscoring the lack of effective medical therapies for this disease. In the United States alone, approximately 40,000 patients die of this disease annually. In November 2012, the NHLBI held a workshop aimed at coordinating research efforts and accelerating the development of IPF therapies. Basic, translational, and clinical researchers gathered with representatives from the NHLBI, patient advocacy groups, pharmaceutical companies, and the U.S. Food and Drug Administration to review the current state of IPF research and identify priority areas, opportunities for collaborations, and directions for future research. The workshop was organized into groups that were tasked with assessing and making recommendations to promote progress in one of the following six critical areas of research: (1) biology of alveolar epithelial injury and aberrant repair; (2) role of extracellular matrix; (3) preclinical modeling; (4) role of inflammation and immunity; (5) genetic, epigenetic, and environmental determinants; (6) translation of discoveries into diagnostics and therapeutics. The workshop recommendations provide a basis for directing future research and strategic planning by scientific, professional, and patient communities and the NHLBI.
Collapse
|
28
|
Kumar V, Mundra V, Mahato RI. Nanomedicines of Hedgehog inhibitor and PPAR-γ agonist for treating liver fibrosis. Pharm Res 2013; 31:1158-69. [PMID: 24249038 DOI: 10.1007/s11095-013-1239-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Accepted: 10/20/2013] [Indexed: 01/01/2023]
Abstract
PURPOSE Hedgehog (Hh) and peroxisome proliferator-activated receptor gamma (PPAR-γ) are major signaling pathways involved in the pathogenesis of liver fibrosis. Since Hh inhibitor, vismodegib (GDC) and PPAR-γ agonist, rosiglitazone (RSG) have poor water solubility, our objective was to formulate biodegradable polymeric nanoparticles encapsulating GDC and RSG for treating liver fibrosis. METHODS Methoxy-polyethylene-glycol-b-poly(carbonate-co-lactide) [mPEG-b-p(CB-co-LA)] was synthesized and characterized using (1)H NMR. Nanoparticles were prepared using this polymer by emulsification/solvent evaporation method to encapsulate GDC and RSG either alone or in combination. Nanoparticles were characterized for particle size, drug loading, drug release, and anti-fibrotic efficacy after tail vein injection into common bile duct ligated (CBDL) fibrotic rats. RESULTS mPEG-b-p(CB-co-LA) copolymer has molecular weight of 30,000 Da as determined by (1)H NMR. Nanoparticles were monodisperse with a mean particle size of 120-130 nm. Drug loading was 5% and 2% w/w for GDC and RSG, respectively. Nanoparticles carrying both GDC and RSG were formulated at half of their individual drug loading. Systemic administration of drug loaded nanoparticles protected liver injury in CBDL rats by suppressing the activation of hepatic stellate cells, and decreasing inflammatory cytokines. CONCLUSION Polymeric nanoparticles for co-delivery of Hh inhibitor and PPAR-γ agonist have the potential to treat liver fibrosis by intervening complex fibrotic cascade.
Collapse
Affiliation(s)
- Virender Kumar
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, Tennessee, 38163, USA
| | | | | |
Collapse
|
29
|
Abstract
OBJECTIVES Biliary atresia (BA) is a rapidly progressive form of biliary fibrosis affecting neonates. We previously reported that primary cilia on the intrahepatic cholangiocytes of patients with both syndromic and nonsyndromic BA were structurally abnormal. Our objective was to determine whether extrahepatic cholangiocytes in human biliary atresia, intrahepatic and extrahepatic cholangiocytes of rhesus rotavirus (RRV)-infected neonatal mice, and RRV-infected primary neonatal extrahepatic cholangiocytes also demonstrate ciliary abnormalities. METHODS The livers of neonatal BALB/c mice injected with RRV that developed jaundice, human extrahepatic bile duct samples obtained at time of hepatoportoenterostomy, and RRV-infected primary neonatal cholangiocytes were stained with antibodies against acetylated α tubulin to identify primary cilia. RESULTS Extrahepatic cholangiocytes from RRV-treated mice demonstrated minimal loss of primary cilia at day 3 but almost complete loss at day 8 and partial loss at day 12. No changes were seen in mouse intrahepatic bile ducts at any of the time points. In the human BA samples, primary cilia were almost completely absent from extrahepatic duct cholangiocytes. There were, however, abundant cilia in the peribiliary glands adjacent to extrahepatic ducts in the BA sample. Cilia in RRV-infected primary neonatal cholangiocytes were significantly decreased compared with controls. CONCLUSIONS Primary cilia are selectively lost from neonatal extrahepatic but not intrahepatic cholangiocytes after RRV infection in BALB/c mice. The cilia are also decreased in RRV-infected primary cholangiocytes and the extrahepatic ducts from human patients with BA. This suggests that ciliary abnormalities are part of the pathophysiology of BA.
Collapse
|
30
|
Regulation and Relevance of Myofibroblast Responses in Idiopathic Pulmonary Fibrosis. CURRENT PATHOBIOLOGY REPORTS 2013; 1:199-208. [PMID: 25705577 DOI: 10.1007/s40139-013-0017-8] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Idiopathic Pulmonary Fibrosis (IPF) is a chronic, progressive, incurable lung disease of unknown etiology with only limited treatment options. Current paradigms of disease pathogenesis feature recurrent or prolonged epithelial injury and an ensuing inflammatory response that culminates in the appearance of activated myofibroblasts. These cells are believed central to the excessive deposition of extracellular matrix that eventually obliterates the alveolar space to cause respiratory failure. Because the factors driving the accumulation of myofibroblasts remain poorly understood, effective therapies remain elusive. This review focuses on recent understanding of myofibroblasts including their seemingly uncontrolled proliferation and survival, their controversial origin in pathological IPF tissues, and the local biochemical and biomechanical matrix factors that drive their behavior. In addition, novel antifibrotics under development for the treatment of lung disease will be discussed. As our understanding of fibroblast and myofibroblast biology regulation expands, these cells may prove to be effective therapeutic targets.
Collapse
|
31
|
Activation of beta 1 but not beta 3 integrin increases cell traction forces. FEBS Lett 2013; 587:763-9. [PMID: 23395612 DOI: 10.1016/j.febslet.2013.01.068] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Revised: 01/03/2013] [Accepted: 01/28/2013] [Indexed: 01/22/2023]
Abstract
Cell-generated traction forces induce integrin activation, leading to focal adhesion growth and cell spreading. It remains unknown, however, whether integrin activation feeds back to impact the generation of cytoskeletal tension. Here, we used elastomeric micropost arrays to measure cellular traction forces in wildtype and integrin-null cells. We report that activation of β1 but not β3 integrin, by either increasing density of immobilized fibronectin or treating with manganese, elicited fibroblast spreading and cytoskeletal tension. Furthermore, this force generation required Rho kinase and myosin activity. These findings suggest that integrin activation and cell traction forces comprise a bi-directional signaling unit of cell adhesion.
Collapse
|