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Perreault LR, Daley MC, Watson MC, Rastogi S, Jaiganesh A, Porter EC, Duffy BM, Black LD. Characterization of cardiac fibroblast-extracellular matrix crosstalk across developmental ages provides insight into age-related changes in cardiac repair. Front Cell Dev Biol 2024; 12:1279932. [PMID: 38434619 PMCID: PMC10904575 DOI: 10.3389/fcell.2024.1279932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 01/22/2024] [Indexed: 03/05/2024] Open
Abstract
Heart failure afflicts an estimated 6.5 million people in the United States, driven largely by incidents of coronary heart disease (CHD). CHD leads to heart failure due to the inability of adult myocardial tissue to regenerate after myocardial infarction (MI). Instead, immune cells and resident cardiac fibroblasts (CFs), the cells responsible for the maintenance of the cardiac extracellular matrix (cECM), drive an inflammatory wound healing response, which leads to fibrotic scar tissue. However, fibrosis is reduced in fetal and early (<1-week-old) neonatal mammals, which exhibit a transient capability for regenerative tissue remodeling. Recent work by our laboratory and others suggests this is in part due to compositional differences in the cECM and functional differences in CFs with respect to developmental age. Specifically, fetal cECM and CFs appear to mitigate functional loss in MI models and engineered cardiac tissues, compared to adult CFs and cECM. We conducted 2D studies of CFs on solubilized fetal and adult cECM to investigate whether these age-specific functional differences are synergistic with respect to their impact on CF phenotype and, therefore, cardiac wound healing. We found that the CF migration rate and stiffness vary with respect to cell and cECM developmental age and that CF transition to a fibrotic phenotype can be partially attenuated in the fetal cECM. However, this effect was not observed when cells were treated with cytokine TGF-β1, suggesting that inflammatory signaling factors are the dominant driver of the fibroblast phenotype. This information may be valuable for targeted therapies aimed at modifying the CF wound healing response and is broadly applicable to age-related studies of cardiac remodeling.
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Affiliation(s)
- Luke R. Perreault
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Mark C. Daley
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Matthew C. Watson
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Sagar Rastogi
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Ajith Jaiganesh
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Elizabeth C. Porter
- Cellular, Molecular and Developmental Biology Program, Graduate School for Biomedical Sciences, Tufts University School of Medicine, Boston, MA, United States
| | - Breanna M. Duffy
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Lauren D. Black
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
- Cellular, Molecular and Developmental Biology Program, Graduate School for Biomedical Sciences, Tufts University School of Medicine, Boston, MA, United States
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Garza MC, Kang SG, Kim C, Monleón E, van der Merwe J, Kramer DA, Fahlman R, Sim VL, Aiken J, McKenzie D, Cortez LM, Wille H. In Vitro and In Vivo Evidence towards Fibronectin's Protective Effects against Prion Infection. Int J Mol Sci 2023; 24:17525. [PMID: 38139358 PMCID: PMC10743696 DOI: 10.3390/ijms242417525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 12/08/2023] [Accepted: 12/09/2023] [Indexed: 12/24/2023] Open
Abstract
A distinctive signature of the prion diseases is the accumulation of the pathogenic isoform of the prion protein, PrPSc, in the central nervous system of prion-affected humans and animals. PrPSc is also found in peripheral tissues, raising concerns about the potential transmission of pathogenic prions through human food supplies and posing a significant risk to public health. Although muscle tissues are considered to contain levels of low prion infectivity, it has been shown that myotubes in culture efficiently propagate PrPSc. Given the high consumption of muscle tissue, it is important to understand what factors could influence the establishment of a prion infection in muscle tissue. Here we used in vitro myotube cultures, differentiated from the C2C12 myoblast cell line (dC2C12), to identify factors affecting prion replication. A range of experimental conditions revealed that PrPSc is tightly associated with proteins found in the systemic extracellular matrix, mostly fibronectin (FN). The interaction of PrPSc with FN decreased prion infectivity, as determined by standard scrapie cell assay. Interestingly, the prion-resistant reserve cells in dC2C12 cultures displayed a FN-rich extracellular matrix while the prion-susceptible myotubes expressed FN at a low level. In agreement with the in vitro results, immunohistopathological analyses of tissues from sheep infected with natural scrapie demonstrated a prion susceptibility phenotype linked to an extracellular matrix with undetectable levels of FN. Conversely, PrPSc deposits were not observed in tissues expressing FN. These data indicate that extracellular FN may act as a natural barrier against prion replication and that the extracellular matrix composition may be a crucial feature determining prion tropism in different tissues.
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Affiliation(s)
- M. Carmen Garza
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada; (M.C.G.); (S.-G.K.); (J.v.d.M.); (V.L.S.); (D.M.)
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Sang-Gyun Kang
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada; (M.C.G.); (S.-G.K.); (J.v.d.M.); (V.L.S.); (D.M.)
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Chiye Kim
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada; (M.C.G.); (S.-G.K.); (J.v.d.M.); (V.L.S.); (D.M.)
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Eva Monleón
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Departamento de Anatomía e Histología Humana, Universidad de Zaragoza, IA2, IIS Aragón, 50013 Zaragoza, Spain
| | - Jacques van der Merwe
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada; (M.C.G.); (S.-G.K.); (J.v.d.M.); (V.L.S.); (D.M.)
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - David A. Kramer
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB T6G 1C9, Canada
| | - Richard Fahlman
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Valerie L. Sim
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada; (M.C.G.); (S.-G.K.); (J.v.d.M.); (V.L.S.); (D.M.)
- Department of Medicine, University of Alberta, Edmonton, AB T6G 2G3, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Judd Aiken
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada; (M.C.G.); (S.-G.K.); (J.v.d.M.); (V.L.S.); (D.M.)
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1, Canada
- Department of Agriculture, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 1C9, Canada
| | - Debbie McKenzie
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada; (M.C.G.); (S.-G.K.); (J.v.d.M.); (V.L.S.); (D.M.)
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Leonardo M. Cortez
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada; (M.C.G.); (S.-G.K.); (J.v.d.M.); (V.L.S.); (D.M.)
- Department of Medicine, University of Alberta, Edmonton, AB T6G 2G3, Canada
| | - Holger Wille
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada; (M.C.G.); (S.-G.K.); (J.v.d.M.); (V.L.S.); (D.M.)
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1, Canada
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3
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Myostatin deficiency decreases cardiac extracellular matrix in pigs. Transgenic Res 2022; 31:553-565. [PMID: 35978205 DOI: 10.1007/s11248-022-00322-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 08/03/2022] [Indexed: 10/15/2022]
Abstract
Myostatin (MSTN), a member of the TGF-β superfamily, negatively regulates muscle growth. MSTN inhibition has been known to cause a double-muscled phenotype in skeletal muscle and fibrosis reduction in the heart. However, the role of MSTN in the cardiac extracellular matrix (ECM) needs more studies in various species of animal models to draw more objective conclusions. The main objective of the present study was to investigate whether loss of MSTN affects the cardiac extracellular matrix in pigs. Three MSTN knockouts (MSTN-/-) and three wild type (WT) male pigs were generated by crossing MSTN ± heterozygous gilts and boars. Cardiac ECM and underlying mechanisms were determined post-mortem. The role of MSTN on collagen expression was investigated by treating cardiac fibroblasts with active MSTN protein in vitro. MSTN protein was detected in WT hearts, while no expression was detected in MSTN-/- hearts. The heart-to-body weight ratio was significantly decreased in MSTN-/- pigs. The morphometric analyses, including picrosirius red staining, immunofluorescent staining, and ultra-structural thickness examination of the endomysium, revealed a significant reduction of connective tissue content in MSTN-/- hearts compared to WT. Hydroxyproline, type I collagen (Col1A), and p-Smad3/Smad3 levels were significantly lower in MSTN-/- hearts in vivo. On the contrary, cardiac fibroblasts treated with exogenous MSTN protein overexpressed Col1A and activated Smad and AKT signaling pathways in vitro. The present study suggests that inhibition of MSTN decreases cardiac extracellular matrix.
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Kuwabara JT, Hara A, Heckl JR, Peña B, Bhutada S, DeMaris R, Ivey MJ, DeAngelo LP, Liu X, Park J, Jahansooz JR, Mestroni L, McKinsey TA, Apte SS, Tallquist MD. Regulation of extracellular matrix composition by fibroblasts during perinatal cardiac maturation. J Mol Cell Cardiol 2022; 169:84-95. [PMID: 35569524 PMCID: PMC10149041 DOI: 10.1016/j.yjmcc.2022.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 05/05/2022] [Accepted: 05/08/2022] [Indexed: 01/18/2023]
Abstract
BACKGROUND Cardiac fibroblasts are the main non-myocyte population responsible for extracellular matrix (ECM) production. During perinatal development, fibroblast expansion coincides with the transition from hyperplastic to hypertrophic myocardial growth. Therefore, we investigated the consequences of fibroblast loss at the time of cardiomyocyte maturation by depleting fibroblasts in the perinatal mouse. METHODS AND RESULTS We evaluated the microenvironment of the perinatal heart in the absence of fibroblasts and the potential functional impact of fibroblast loss in regulation of cardiomyocyte cell cycle arrest and binucleation. Cre-mediated expression of diphtheria toxin A in PDGFRα expressing cells immediately after birth eliminated 70-80% of the cardiac fibroblasts. At postnatal day 5, hearts lacking fibroblasts appeared similar to controls with normal morphology and comparable numbers of endothelial and smooth muscle cells, despite a pronounced reduction in fibrillar collagen. Immunoblotting and proteomic analysis of control and fibroblast-deficient hearts identified differential abundance of several ECM proteins. In addition, fibroblast loss decreased tissue stiffness and resulted in increased cardiomyocyte mitotic index, DNA synthesis, and cytokinesis. Moreover, decellularized matrix from fibroblast-deficient hearts promoted cardiomyocyte DNA replication. While cardiac architecture was not overtly affected by fibroblast reduction, few pups survived past postnatal day 11, suggesting an overall requirement for PDGFRα expressing fibroblasts. CONCLUSIONS These studies demonstrate the key role of fibroblasts in matrix production and cardiomyocyte cross-talk during mouse perinatal heart maturation and revealed that fibroblast-derived ECM may modulate cardiomyocyte maturation in vivo. Neonatal depletion of fibroblasts demonstrated that although hearts can tolerate reduced ECM composition, fibroblast loss eventually leads to perinatal death as the approach simultaneously reduced fibroblast populations in other organs.
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Affiliation(s)
- Jill T Kuwabara
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, United States of America; Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, United States of America
| | - Akitoshi Hara
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, United States of America
| | - Jack R Heckl
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, United States of America; Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, United States of America
| | - Brisa Peña
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, United States of America; Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, United States of America; Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, United States of America
| | - Sumit Bhutada
- Department of Biomedical Engineering, Cleveland Clinic Lerner Research Institute, Cleveland, OH 44195, United States of America
| | - Regan DeMaris
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, United States of America
| | - Malina J Ivey
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, United States of America; Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, United States of America; Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, OH 45267, United States of America
| | - Lydia P DeAngelo
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, United States of America
| | - Xiaoting Liu
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, United States of America
| | - Juwon Park
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, United States of America
| | - Julia R Jahansooz
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, United States of America
| | - Luisa Mestroni
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, United States of America
| | - Timothy A McKinsey
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, United States of America; Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, United States of America
| | - Suneel S Apte
- Department of Biomedical Engineering, Cleveland Clinic Lerner Research Institute, Cleveland, OH 44195, United States of America
| | - Michelle D Tallquist
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, United States of America.
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Ambade AS, Hassoun PM, Damico RL. Basement Membrane Extracellular Matrix Proteins in Pulmonary Vascular and Right Ventricular Remodeling in Pulmonary Hypertension. Am J Respir Cell Mol Biol 2021; 65:245-258. [PMID: 34129804 PMCID: PMC8485997 DOI: 10.1165/rcmb.2021-0091tr] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 06/14/2021] [Indexed: 12/13/2022] Open
Abstract
The extracellular matrix (ECM), a highly organized network of structural and nonstructural proteins, plays a pivotal role in cellular and tissue homeostasis. Changes in the ECM are critical for normal tissue repair, whereas dysregulation contributes to aberrant tissue remodeling. Pulmonary arterial hypertension is a severe disorder of the pulmonary vasculature characterized by pathologic remodeling of the pulmonary vasculature and right ventricle, increased production and deposition of structural and nonstructural proteins, and altered expression of ECM growth factors and proteases. Furthermore, ECM remodeling plays a significant role in disease progression, as several dynamic changes in its composition, quantity, and organization are documented in both humans and animal models of disease. These ECM changes impact vascular cell biology and affect proliferation of resident cells. Furthermore, ECM components determine the tissue architecture of the pulmonary and myocardial vasculature as well as the myocardium itself and provide mechanical stability crucial for tissue homeostasis. However, little is known about the basement membrane (BM), a specialized, self-assembled conglomerate of ECM proteins, during remodeling. In the vasculature, the BM is in close physical association with the vascular endothelium and smooth muscle cells. While in the myocardium, each cardiomyocyte is enclosed by a BM that serves as the interface between cardiomyocytes and the surrounding interstitial matrix. In this review, we provide a brief overview on the current state of knowledge of the BM and its ECM composition and their impact on pulmonary vascular remodeling and right ventricle dysfunction and failure in pulmonary arterial hypertension.
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Affiliation(s)
- Anjira S Ambade
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University, Baltimore, Maryland
| | - Paul M Hassoun
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University, Baltimore, Maryland
| | - Rachel L Damico
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University, Baltimore, Maryland
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The bright side of fibroblasts: molecular signature and regenerative cues in major organs. NPJ Regen Med 2021; 6:43. [PMID: 34376677 PMCID: PMC8355260 DOI: 10.1038/s41536-021-00153-z] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 07/22/2021] [Indexed: 02/07/2023] Open
Abstract
Fibrosis is a pathologic process characterized by the replacement of parenchymal tissue by large amounts of extracellular matrix, which may lead to organ dysfunction and even death. Fibroblasts are classically associated to fibrosis and tissue repair, and seldom to regeneration. However, accumulating evidence supports a pro-regenerative role of fibroblasts in different organs. While some organs rely on fibroblasts for maintaining stem cell niches, others depend on fibroblast activity, particularly on secreted molecules that promote cell adhesion, migration, and proliferation, to guide the regenerative process. Herein we provide an up-to-date overview of fibroblast-derived regenerative signaling across different organs and discuss how this capacity may become compromised with aging. We further introduce a new paradigm for regenerative therapies based on reverting adult fibroblasts to a fetal/neonatal-like phenotype.
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DePalma SJ, Davidson CD, Stis AE, Helms AS, Baker BM. Microenvironmental determinants of organized iPSC-cardiomyocyte tissues on synthetic fibrous matrices. Biomater Sci 2021; 9:93-107. [PMID: 33325920 PMCID: PMC7971708 DOI: 10.1039/d0bm01247e] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cardiomyocytes derived from induced pluripotent stem cells (iPSC-CMs) show great potential for engineering myocardium to study cardiac disease and create regenerative therapies. However, iPSC-CMs typically possess a late embryonic stage phenotype, with cells failing to exhibit markers of mature adult tissue. This is due in part to insufficient knowledge and control of microenvironmental cues required to facilitate the organization and maturation of iPSC-CMs. Here, we employed a cell-adhesive, mechanically tunable synthetic fibrous extracellular matrix (ECM) consisting of electrospun dextran vinyl sulfone (DVS) fibers and examined how biochemical, architectural, and mechanical properties of the ECM impact iPSC-CM tissue assembly and subsequent function. Exploring a multidimensional parameter space spanning cell-adhesive ligand, seeding density, fiber alignment, and stiffness, we found that fibronectin-functionalized DVS matrices composed of highly aligned fibers with low stiffness optimally promoted the organization of functional iPSC-CM tissues. Tissues generated on these matrices demonstrated improved calcium handling and increased end-to-end localization of N-cadherin as compared to micropatterned fibronectin lines or fibronectin-coated glass. Furthermore, DVS matrices supported long-term culture (45 days) of iPSC-CMs; N-cadherin end-to-end localization and connexin43 expression both increased as a function of time in culture. In sum, these findings demonstrate the importance of recapitulating the fibrous myocardial ECM in engineering structurally organized and functional iPSC-CM tissues.
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Affiliation(s)
- Samuel J DePalma
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA.
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Besser RR, Ishahak M, Mayo V, Carbonero D, Claure I, Agarwal A. Engineered Microenvironments for Maturation of Stem Cell Derived Cardiac Myocytes. Am J Cancer Res 2018; 8:124-140. [PMID: 29290797 PMCID: PMC5743464 DOI: 10.7150/thno.19441] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 10/19/2017] [Indexed: 01/11/2023] Open
Abstract
Through the use of stem cell-derived cardiac myocytes, tissue-engineered human myocardial constructs are poised for modeling normal and diseased physiology of the heart, as well as discovery of novel drugs and therapeutic targets in a human relevant manner. This review highlights the recent bioengineering efforts to recapitulate microenvironmental cues to further the maturation state of newly differentiated cardiac myocytes. These techniques include long-term culture, co-culture, exposure to mechanical stimuli, 3D culture, cell-matrix interactions, and electrical stimulation. Each of these methods has produced various degrees of maturation; however, a standardized measure for cardiomyocyte maturation is not yet widely accepted by the scientific community.
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Daley MC, Fenn SL, Black LD. Applications of Cardiac Extracellular Matrix in Tissue Engineering and Regenerative Medicine. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1098:59-83. [PMID: 30238366 DOI: 10.1007/978-3-319-97421-7_4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The role of the cardiac extracellular matrix (cECM) in providing biophysical and biochemical cues to the cells housed within during disease and development has become increasingly apparent. These signals have been shown to influence many fundamental cardiac cell behaviors including contractility, proliferation, migration, and differentiation. Consequently, alterations to cell phenotype result in directed remodeling of the cECM. This bidirectional communication means that the cECM can be envisioned as a medium for information storage. As a result, the reprogramming of the cECM is increasingly being employed in tissue engineering and regenerative medicine as a method with which to treat disease. In this chapter, an overview of the composition and structure of the cECM as well as its role in cardiac development and disease will be provided. Additionally, therapeutic modulation of cECM for cardiac regeneration as well as bottom-up and top-down approaches to ECM-based cardiac tissue engineering is discussed. Finally, lingering questions regarding the role of cECM in tissue engineering and regenerative medicine are offered as a catalyst for future research.
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Affiliation(s)
- Mark C Daley
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
| | - Spencer L Fenn
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
- Center for Biomedical Career Development, University of Massachusetts Medical School, Worcester, MA, USA
| | - Lauren D Black
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA.
- Cellular, Molecular and Developmental Biology Program, Sackler School for Graduate Biomedical Sciences, Tufts University School of Medicine, Boston, MA, USA.
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10
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Pellman J, Zhang J, Sheikh F. Myocyte-fibroblast communication in cardiac fibrosis and arrhythmias: Mechanisms and model systems. J Mol Cell Cardiol 2016; 94:22-31. [PMID: 26996756 DOI: 10.1016/j.yjmcc.2016.03.005] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 02/27/2016] [Accepted: 03/14/2016] [Indexed: 12/17/2022]
Abstract
Development of cardiac fibrosis and arrhythmias is controlled by the activity of and communication between cardiomyocytes and fibroblasts in the heart. Myocyte-fibroblast interactions occur via both direct and indirect means including paracrine mediators, extracellular matrix interactions, electrical modulators, mechanical junctions, and membrane nanotubes. In the diseased heart, cardiomyocyte and fibroblast ratios and activity, and thus myocyte-fibroblast interactions, change and are thought to contribute to the course of disease including development of fibrosis and arrhythmogenic activity. Fibroblasts have a developing role in modulating cardiomyocyte electrical and hypertrophic activity, however gaps in knowledge regarding these interactions still exist. Research in this field has necessitated the development of unique approaches to isolate and control myocyte-fibroblast interactions. Numerous methods for 2D and 3D co-culture systems have been developed, while a growing part of this field is in the use of better tools for in vivo systems including cardiomyocyte and fibroblast specific Cre mouse lines for cell type specific genetic ablation. This review will focus on (i) mechanisms of myocyte-fibroblast communication and their effects on disease features such as cardiac fibrosis and arrhythmias as well as (ii) methods being used and currently developed in this field.
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Affiliation(s)
- Jason Pellman
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Jing Zhang
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Farah Sheikh
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.
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Thimm TN, Squirrell JM, Liu Y, Eliceiri KW, Ogle BM. Endogenous Optical Signals Reveal Changes of Elastin and Collagen Organization During Differentiation of Mouse Embryonic Stem Cells. Tissue Eng Part C Methods 2015; 21:995-1004. [PMID: 25923353 DOI: 10.1089/ten.tec.2014.0699] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Components of the extracellular matrix (ECM) have recently been shown to influence stem cell specification. However, it has been challenging to assess the spatial and temporal dynamics of stem cell-ECM interactions because most methodologies utilized to date require sample destruction or fixation. We examined the efficacy of utilizing the endogenous optical signals of two important ECM proteins, elastin (Eln), through autofluorescence, and type I collagen (ColI), through second harmonic generation (SHG), during mouse embryonic stem cell differentiation. After finding favorable overlap between antibody labeling and the endogenous fluorescent signal of Eln, we used this endogenous signal to map temporal changes in Eln and ColI during murine embryoid body differentiation and found that Eln increases until day 9 and then decreases slightly by day 12, while Col1 steadily increases over the 12-day period. Furthermore, we combined endogenous fluorescence imaging and SHG with antibody labeling of cardiomyocytes to examine the spatial relationship between Eln and ColI accumulation and cardiomyocyte differentiation. Eln was ubiquitously present, with enrichment in regions with cardiomyocyte differentiation, while there was an inverse correlation between ColI and cardiomyocyte differentiation. This work provides an important first step for utilizing endogenous optical signals, which can be visualized in living cells, to understand the relationship between the ECM and cardiomyocyte development and sets the stage for future studies of stem cell-ECM interactions and dynamics relevant to stem cells as well as other cell and tissue types.
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Affiliation(s)
- Terra N Thimm
- 1 Laboratory for Optical and Computational Instrumentation, University of Wisconsin-Madison , Madison, Wisconsin
| | - Jayne M Squirrell
- 1 Laboratory for Optical and Computational Instrumentation, University of Wisconsin-Madison , Madison, Wisconsin
| | - Yuming Liu
- 1 Laboratory for Optical and Computational Instrumentation, University of Wisconsin-Madison , Madison, Wisconsin
| | - Kevin W Eliceiri
- 1 Laboratory for Optical and Computational Instrumentation, University of Wisconsin-Madison , Madison, Wisconsin.,2 Morgridge Institute for Research, University of Wisconsin-Madison , Madison, Wisconsin
| | - Brenda M Ogle
- 3 Department of Biomedical Engineering, University of Minnesota-Twin Cities , Minneapolis, Minnesota
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Williams C, Budina E, Stoppel WL, Sullivan KE, Emani S, Emani SM, Black LD. Cardiac extracellular matrix-fibrin hybrid scaffolds with tunable properties for cardiovascular tissue engineering. Acta Biomater 2015; 14:84-95. [PMID: 25463503 PMCID: PMC4308538 DOI: 10.1016/j.actbio.2014.11.035] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Revised: 11/15/2014] [Accepted: 11/18/2014] [Indexed: 12/23/2022]
Abstract
Solubilized cardiac extracellular matrix (ECM) is being developed as an injectable therapeutic that offers promise for promoting cardiac repair. However, the ECM alone forms a hydrogel that is very soft compared to the native myocardium. As both the stiffness and composition of the ECM are important in regulating cell behavior and can have complex synergistic effects, we sought to develop an ECM-based scaffold with tunable biochemical and mechanical properties. We used solubilized rat cardiac ECM from two developmental stages (neonatal, adult) combined with fibrin hydrogels that were cross-linked with transglutaminase. We show that ECM was retained within the gels and that the Young's modulus could be tuned to span the range of the developing and mature heart. C-kit+ cardiovascular progenitor cells from pediatric patients with congenital heart defects were seeded into the hybrid gels. Both the elastic modulus and composition of the scaffolds impacted the expression of endothelial and smooth muscle cell genes. Furthermore, we demonstrate that the hybrid gels are injectable, and thus have potential for minimally invasive therapies. ECM-fibrin hybrid scaffolds offer new opportunities for exploiting the effects of both composition and mechanical properties in directing cell behavior for tissue engineering.
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Affiliation(s)
- Corin Williams
- Department of Biomedical Engineering, Tufts University, 4 Colby St, Medford, MA 02155, USA
| | - Erica Budina
- Department of Biomedical Engineering, Tufts University, 4 Colby St, Medford, MA 02155, USA
| | - Whitney L Stoppel
- Department of Biomedical Engineering, Tufts University, 4 Colby St, Medford, MA 02155, USA
| | - Kelly E Sullivan
- Department of Biomedical Engineering, Tufts University, 4 Colby St, Medford, MA 02155, USA
| | - Sirisha Emani
- Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Ave, Boston, MA 02115, USA
| | - Sitaram M Emani
- Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Ave, Boston, MA 02115, USA
| | - Lauren D Black
- Department of Biomedical Engineering, Tufts University, 4 Colby St, Medford, MA 02155, USA; Cellular, Molecular and Developmental Biology Program, Sackler School for Graduate Biomedical Sciences, Tufts University School of Medicine, 145 Harrison Ave, Boston, MA 02111, USA.
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13
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Young developmental age cardiac extracellular matrix promotes the expansion of neonatal cardiomyocytes in vitro. Acta Biomater 2014; 10:194-204. [PMID: 24012606 DOI: 10.1016/j.actbio.2013.08.037] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 08/01/2013] [Accepted: 08/27/2013] [Indexed: 02/02/2023]
Abstract
A major limitation to cardiac tissue engineering and regenerative medicine strategies is the lack of proliferation of postnatal cardiomyocytes. The extracellular matrix (ECM) is altered during heart development, and studies suggest that it plays an important role in regulating myocyte proliferation. Here, the effects of fetal, neonatal and adult cardiac ECM on the expansion of neonatal rat ventricular cells in vitro are studied. At 24h, overall cell attachment was lowest on fetal ECM; however, ~80% of the cells were cardiomyocytes, while many non-myocytes attached to older ECM and poly-l-lysine controls. After 5 days, the cardiomyocyte population remained highest on fetal ECM, with a 4-fold increase in number. Significantly more cardiomyocytes stained positively for the mitotic marker phospho-histone H3 on fetal ECM compared with other substrates at 5 days, suggesting that proliferation may be a major mechanism of cardiomyocyte expansion on young ECM. Further study of the beneficial properties of early developmental aged cardiac ECM could advance the design of novel biomaterials aimed at promoting cardiac regeneration.
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14
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Gershlak JR, Resnikoff JIN, Sullivan KE, Williams C, Wang RM, Black LD. Mesenchymal stem cells ability to generate traction stress in response to substrate stiffness is modulated by the changing extracellular matrix composition of the heart during development. Biochem Biophys Res Commun 2013; 439:161-6. [PMID: 23994333 DOI: 10.1016/j.bbrc.2013.08.074] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 08/21/2013] [Indexed: 01/01/2023]
Abstract
In this study we present a novel method for studying cellular traction force generation and mechanotransduction in the context of cardiac development. Rat hearts from three distinct stage of development (fetal, neonatal and adult) were isolated, decellularized and characterized via mechanical testing and protein compositional analysis. Stiffness increased ~2-fold between fetal and neonatal time points but not between neonatal and adult. Composition of structural extracellular matrix (ECM) proteins was significantly different between all three developmental ages. ECM that was solubilized via pepsin digestion was cross-linked into polyacrylamide gels of varying stiffness and traction force microscopy was used to assess the ability of mesenchymal stem cells (MSCs) to generate traction stress against the substrates. The response to increasing stiffness was significantly different depending on the developmental age of the ECM. An investigation into early cardiac differentiation of MSCs demonstrated a dependence of the level of expression of early cardiac transcription factors on the composition of the complex ECM. In summary, this study found that complex ECM composition plays an important role in modulating a cell's ability to generate traction stress against a substrate, which is a significant component of mechanotransductive signaling.
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Affiliation(s)
- Joshua R Gershlak
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
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15
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Sheehy SP, Grosberg A, Parker KK. The contribution of cellular mechanotransduction to cardiomyocyte form and function. Biomech Model Mechanobiol 2012; 11:1227-39. [PMID: 22772714 DOI: 10.1007/s10237-012-0419-2] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 06/25/2012] [Indexed: 01/07/2023]
Abstract
Myocardial development is regulated by an elegantly choreographed ensemble of signaling events mediated by a multitude of intermediates that take a variety of forms. Cellular differentiation and maturation are a subset of vertically integrated processes that extend over several spatial and temporal scales to create a well-defined collective of cells that are able to function cooperatively and reliably at the organ level. Early efforts to understand the molecular mechanisms of cardiomyocyte fate determination focused primarily on genetic and chemical mediators of this process. However, increasing evidence suggests that mechanical interactions between the extracellular matrix (ECM) and cell surface receptors as well as physical interactions between neighboring cells play important roles in regulating the signaling pathways controlling the developmental processes of the heart. Interdisciplinary efforts have made it apparent that the influence of the ECM on cellular behavior occurs through a multitude of physical mechanisms, such as ECM boundary conditions, elasticity, and the propagation of mechanical signals to intracellular compartments, such as the nucleus. In addition to experimental studies, a number of mathematical models have been developed that attempt to capture the interplay between cells and their local microenvironment and the influence these interactions have on cellular self-assembly and functional behavior. Nevertheless, many questions remain unanswered concerning the mechanism through which physical interactions between cardiomyocytes and their environment are translated into biochemical cellular responses and how these signaling modalities can be utilized in vitro to fabricate myocardial tissue constructs from stem cell-derived cardiomyocytes that more faithfully represent their in vivo counterpart. These studies represent a broad effort to characterize biological form as a conduit for information transfer that spans the nanometer length scale of proteins to the meter length scale of the patient and may yield new insights into the contribution of mechanotransduction into heart development and disease.
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Affiliation(s)
- Sean P Sheehy
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, School of Engineering and Applied Sciences, Harvard University, Pierce Hall Rm. 321, 29 Oxford St., Cambridge, MA 02138, USA
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16
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Cooperative coupling of cell-matrix and cell-cell adhesions in cardiac muscle. Proc Natl Acad Sci U S A 2012; 109:9881-6. [PMID: 22675119 DOI: 10.1073/pnas.1203007109] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Adhesion between cardiac myocytes is essential for the heart to function as an electromechanical syncytium. Although cell-matrix and cell-cell adhesions reorganize during development and disease, the hierarchical cooperation between these subcellular structures is poorly understood. We reasoned that, during cardiac development, focal adhesions mechanically stabilize cells and tissues during myofibrillogenesis and intercalated disc assembly. As the intercalated disc matures, we postulated that focal adhesions disassemble as systolic stresses are transmitted intercellularly. Finally, we hypothesized that pathological remodeling of cardiac microenvironments induces excessive mechanical loading of intercalated discs, leading to assembly of stabilizing focal adhesions adjacent to the junction. To test our model, we engineered μtissues composed of two ventricular myocytes on deformable substrates of tunable elasticity to measure the dynamic organization and functional remodeling of myofibrils, focal adhesions, and intercalated discs as cooperative ensembles. Maturing μtissues increased systolic force while simultaneously developing into an electromechanical syncytium by disassembling focal adhesions at the cell-cell interface and forming mature intercalated discs that transmitted the systolic load. We found that engineering the microenvironment to mimic fibrosis resulted in focal adhesion formation adjacent to the cell-cell interface, suggesting that the intercalated disc required mechanical reinforcement. In these pathological microenvironments, μtissues exhibited further evidence of maladaptive remodeling, including lower work efficiency, longer contraction cycle duration, and weakened relationships between cytoskeletal organization and force generation. These results suggest that the cooperative balance between cell-matrix and cell-cell adhesions in the heart is guided by an architectural and functional hierarchy established during development and disrupted during disease.
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17
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Extracellular matrix composition of the cricopharyngeus muscle. Dysphagia 2011; 27:277-83. [PMID: 21874509 DOI: 10.1007/s00455-011-9364-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Accepted: 08/03/2011] [Indexed: 10/17/2022]
Abstract
The aim of this study was to analyze the presence and distribution of total collagen, type I and type III collagen, elastic fibers, fibronectin, and versican in the endomysium of cricopharyngeus muscles from adults of various ages. The study was a cross-sectional analysis of human cricopharyngeus muscles. Twenty-seven muscles obtained from autopsies of men and women ranging in age from 28 to 92 years were analyzed with the Picrosirius method, oxidized Weigert resorcin-fuchsin, immunohistochemistry, and image analysis. Collagen had the highest density among the analyzed components. Elastic fibers surrounded each muscle cell; they were aligned longitudinally by their long axis and associated with traversing fibers, thereby forming a fiber network with embedded muscle cells. The fibronectin and versican contents varied widely among the specimens. We found no statistically significant differences between the proportion of extracellular matrix (ECM) components and factors such as gender and race. We conclude that the higher proportion of type I and type III collagen is compatible with the cricopharyngeus muscle's sphincteric behavior, and the arrangement of the elastic fibers may also contribute to the muscle's elasticity. We found no statistically significant correlation between the ECM components and age.
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18
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Mechanotransduction: the role of mechanical stress, myocyte shape, and cytoskeletal architecture on cardiac function. Pflugers Arch 2011; 462:89-104. [PMID: 21499986 DOI: 10.1007/s00424-011-0951-4] [Citation(s) in RCA: 144] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2011] [Accepted: 02/27/2011] [Indexed: 12/16/2022]
Abstract
Mechanotransduction refers to the conversion of mechanical forces into biochemical or electrical signals that initiate structural and functional remodeling in cells and tissues. The heart is a kinetic organ whose form changes considerably during development and disease, requiring cardiac myocytes to be mechanically durable and capable of fusing a variety of environmental signals on different time scales. During physiological growth, myocytes adaptively remodel to mechanical loads. Pathological stimuli can induce maladaptive remodeling. In both of these conditions, the cytoskeleton plays a pivotal role in both sensing mechanical stress and mediating structural remodeling and functional responses within the myocyte.
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19
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Baldinger A, Brehm BR, Richter P, Bossert T, Gruen K, Hekmat K, Kosmehl H, Neri D, Figulla HR, Berndt A, Franz M. Comparative analysis of oncofetal fibronectin and tenascin-C expression in right atrial auricular and left ventricular human cardiac tissue from patients with coronary artery disease and aortic valve stenosis. Histochem Cell Biol 2011; 135:427-41. [PMID: 21479812 DOI: 10.1007/s00418-011-0809-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/26/2011] [Indexed: 12/19/2022]
Abstract
Aortic valve stenosis (AVS) and coronary artery disease (CAD) are accompanied by changes in the cardiac extra cellular matrix (cECM) including the re-expression of oncofetal fibronectin (Fn) and tenascin-C (Tn-C) variants. Human antibodies against these variants are usable for targeted therapy. Aim of the study was the comparative analysis of cECM remodelling in tissue samples from right atrial auricle (RAA) and left ventricular septum (LVS). RAA and LVS specimens from 30 patients (17 × AVS; 13 × AVS+CAD) were analysed with respect to histological changes and ECM remodelling using PCR based ECM gene expression profiling. Re-expression of ED-A(+) Fn and A1(+) Tn-C was investigated on the mRNA and on the protein level. For immunofluorescence, human recombinant small immunoprotein (SIP) format antibodies were used. There was a positive correlation of the grade of histological changes in RAA and corresponding LVS samples (r = 0.695). ECM gene expression levels were higher in LVS compared to RAA. For 24 genes, a corresponding relevant (>2.5-fold) up- or down-regulation in RAA and LVS occurred. Using SIP antibodies, a positive correlation of protein deposition levels in RAA and corresponding LVS (r = 0.818) could be shown for ED-A(+) Fn. Cardiac tissue remodelling is likely a process involving the entire heart reflected by intra-individually comparable histology and cECM changes in RAA and LVS samples. ED-A(+) Fn might be an excellent target for an antibody-mediated delivery of diagnostic or therapeutic agents. The RAA is a valuable and representative tool to evaluate cardiac remodelling and to plan individualized therapy.
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Affiliation(s)
- Anja Baldinger
- Department of Internal Medicine I, University Hospital of Jena, Erlanger Allee 101, 07740, Jena, Germany
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20
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Zhang J, Chang L, Chen C, Zhang M, Luo Y, Hamblin M, Villacorta L, Xiong JW, Chen YE, Zhang J, Zhu X. Rad GTPase inhibits cardiac fibrosis through connective tissue growth factor. Cardiovasc Res 2011; 91:90-8. [PMID: 21382976 DOI: 10.1093/cvr/cvr068] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
AIMS Our previous studies documented that Rad (Ras associated with diabetes), a member of the RGK (Rad, Gem, and Kir) family of Ras-related small G protein, is significantly decreased in human failing hearts and plays an important role in attenuating cardiac hypertrophy. The goal of this study is to identify the effect of Rad on cardiac fibrosis and the underlying mechanisms. METHODS AND RESULTS Rad knockout (KO) mice showed more severe cardiac fibrosis compared with wild-type littermate controls as detected by Sirius Red staining. Western blot analyses demonstrated that the expression of connective tissue growth factor (CTGF), a key mediator of fibrosis, increased dramatically in Rad KO mice. Overexpression of Rad in cultured neonatal cardiomyocytes suppressed both basal and transforming growth factor-β1-induced CTGF expression. Elevated CTGF expression was observed in cardiomyocytes when Rad was reduced by RNA interference. Moreover, cardiac fibroblasts produced greater extracellular matrix (ECM) when stimulated with conditioned medium from Rad-knockdown cardiomyocytes. ECM production was completely abolished by adding a CTGF-neutralizing antibody into the medium. CCAAT/enhancer-binding protein δ (C/EBP-δ) was demonstrated to activate CTGF in cardiomyocytes. Chromatin immunoprecipitation assay and co-immunoprecipitation further demonstrated that Rad inhibited the binding of C/EBP-δ to the CTGF promoter via direct interaction with C/EBP-δ. CONCLUSION Our data reveal that Rad deficiency can lead to cardiac fibrosis. Rad inhibits CTGF expression through binding with C/EBP-δ, thus regulating ECM production in the heart. This study suggests a potential link between decreased Rad levels and increased cardiac fibrosis in human failing hearts.
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Affiliation(s)
- Ji Zhang
- Institute of Molecular Medicine, Peking University, No. 5, Yi He Yuan Road, Beijing 100871, China
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21
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Wu X, Chakraborty S, Heaps CL, Davis MJ, Meininger GA, Muthuchamy M. Fibronectin increases the force production of mouse papillary muscles via α5β1 integrin. J Mol Cell Cardiol 2010; 50:203-13. [PMID: 20937283 DOI: 10.1016/j.yjmcc.2010.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2010] [Revised: 09/30/2010] [Accepted: 10/01/2010] [Indexed: 02/07/2023]
Abstract
The extracellular matrix (ECM) protein-integrin-cytoskeleton axis plays a central role as a mechanotransducing protein assemblage in many cell types. However, how the process of mechanotransduction and the mechanically generated signals arising from this axis affect myofilament function in cardiac muscle are not completely understood. We hypothesize that ECM proteins can regulate cardiac function through integrin binding, and thereby alter the intracellular calcium concentration ([Ca(2+)](i)) and/or modulate myofilament activation processes. Force measurements made in mouse papillary muscle demonstrated that in the presence of the soluble form of the ECM protein, fibronectin (FN), active force was increased significantly by 40% at 1 Hz, 54% at 2 Hz, 35% at 5 Hz and 16% at 9 Hz stimulation frequencies. Furthermore, increased active force in the presence of FN was associated with 12-33% increase in [Ca(2+)](i) and 20-50% increase in active force per unit Ca(2+). A function blocking antibody for α5 integrin prevented the effects of the FN on the changes in force and [Ca(2+)](i), whereas a function blocking α3 integrin antibody did not reverse the effects of FN. The effects of FN were reversed by an L-type Ca(2+) channel blocker, verapamil or PKA inhibitor. Freshly isolated cardiomyocytes exhibited a 39% increase in contraction force and a 36% increase in L-type Ca(2+) current in the presence of FN. Fibers treated with FN showed a significant increase in the phosphorylation of phospholamban; however, the phosphorylation of troponin I was unchanged. These results demonstrate that FN acts via α5β1 integrin to increase force production in myocardium and that this effect is partly mediated by increases in [Ca(2+)](i) and Ca(2+) sensitivity, PKA activation and phosphorylation of phospholamban.
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Affiliation(s)
- Xin Wu
- Department of Systems Biology and Translational Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX 77843, USA
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22
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Franz M, Grün K, Richter P, Brehm BR, Fritzenwanger M, Hekmat K, Neri D, Gummert J, Figulla HR, Kosmehl H, Berndt A, Renner A. Extra cellular matrix remodelling after heterotopic rat heart transplantation: gene expression profiling and involvement of ED-A+ fibronectin, alpha-smooth muscle actin and B+ tenascin-C in chronic cardiac allograft rejection. Histochem Cell Biol 2010; 134:503-17. [PMID: 20931338 DOI: 10.1007/s00418-010-0750-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2010] [Indexed: 11/29/2022]
Abstract
Chronic cardiac rejection is represented by cardiac allograft vasculopathy (CAV) and cardiac interstitial fibrosis (CIF) known to cause severe complications. These processes are accompanied by remarkable changes in the cardiac extra cellular matrix (cECM). The aim of our study was to analyse the cECM remodelling in chronic rejection and to elucidate a potential role of ED-A domain containing fibronectin (ED-A(+) Fn), alpha smooth muscle actin (ASMA) and B domain containing tenascin-C (B(+) Tn-C). A model of chronic rejection after heterotopic rat heart transplantation was used. Allografts, recipient and control hearts were subjected to histological assessment of rejection grade, to real-time PCR based analysis of 84 genes of ECM and adhesion molecules and to immunofluorescence labelling procedures, including ED-A(+) Fn, ASMA and B(+) Tn-C antibodies. Histological analysis revealed different grades of chronic rejection. By gene expression analysis, a relevant up-regulation of the majority of ECM genes in association with chronic rejection could be shown. For 8 genes, there was a relevant up-regulation in allografts as well as in the corresponding recipient hearts. Association of ASMA positive cells with the grade of chronic rejection could be proven. In CAV and also in CIF there were extensive co-depositions of ED-A(+) Fn, ASMA and B(+) Tn-C. In conclusion, chronic cardiac allograft rejection is associated with a cECM remodelling. ASMA protein deposition in CAV, and CIF is a valuable marker to detect chronic rejection. Interactions of VSMCs and Fibro-/Myofibroblasts with ED-A(+) Fn and B(+) Tn-C might functionally contribute to the development of chronic cardiac rejection.
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Affiliation(s)
- Marcus Franz
- Department of Internal Medicine I, University Hospital of Jena, Erlanger Allee 101, 07740, Jena, Germany.
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23
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Franz M, Brehm BR, Richter P, Gruen K, Neri D, Kosmehl H, Hekmat K, Renner A, Gummert J, Figulla HR, Berndt A. Changes in extra cellular matrix remodelling and re-expression of fibronectin and tenascin-C splicing variants in human myocardial tissue of the right atrial auricle: implications for a targeted therapy of cardiovascular diseases using human SIP format antibodies. J Mol Histol 2010; 41:39-50. [PMID: 20232238 DOI: 10.1007/s10735-010-9260-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2009] [Accepted: 02/26/2010] [Indexed: 11/29/2022]
Abstract
Cardiovascular diseases are accompanied by changes in the extracellular matrix (ECM) including the re-expression of fibronectin and tenascin-C splicing variants. Using human recombinant small immunoprotein (SIP) format antibodies, a molecular targeting of these proteins is of therapeutic interest. Tissue samples of the right atrial auricle from patients with coronary artery disease and valvular heart disease were analysed by PCR based ECM gene expression profiling. Moreover, the re-expression of fibronectin and tenascin-C splicing variants was investigated by immunofluoerescence labelling. We demonstrated changes in ECM gene expression depending on histological damage or underlying cardiac disease. An increased expression of fibronectin and tenascin-C mRNA in association to histological damage and in valvular heart disease compared to coronary artery disease could be shown. There was a distinct re-expression of ED-A containing fibronectin and A1 domain containing tenascin-C detectable with human recombinant SIP format antibodies in diseased myocardium. ED-A containing fibronectin showed a clear vessel positivity. For A1 domain containing tenascin-C, there was a particular positivity in areas of interstitial and perivascular fibrosis. Right atrial myocardial tissue is a valuable model to investigate cardiac ECM remodelling. Human recombinant SIP format antibodies usable for an antibody-mediated targeted delivery of drugs might offer completely new therapeutic options in cardiac diseases.
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Affiliation(s)
- Marcus Franz
- Department of Internal Medicine I, University Hospital Jena, Erlanger Allee 101, 07740, Jena, Germany.
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Abstract
Cardiac fibroblasts are emerging as key components of normal cardiac function, as well as the response to stressors and injury. These most numerous cells of the heart interact with myocytes via paracrine mechanisms, alterations in extracellular matrix homeostasis, and direct cell-cell interactions. It is possible that they are a contributor to the inability of adult myocytes to proliferate and may influence cardiac progenitor biology. Furthering our understanding of how cardiac fibroblasts and myocytes interact may provide an avenue to novel treatments for heart failure prevention. This review discusses the most recent concepts in cardiac fibroblast-myocyte communication and areas of potential future research.
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Affiliation(s)
- Rahul Kakkar
- Cardiology Division, Massachusetts General Hospital, Department of Medicine, Harvard Medical School, Boston, MA, USA
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25
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Majak P, Bjørnstad J, Vengen OA, Neverdal NO, Husebye T, Woldbaek P, Pepper J, Lie M, Christensen G, Tønnessen T. Plasma IL-18 and IL-18BP are altered differently in reverse remodeling following aortic valve replacement. SCAND CARDIOVASC J 2009; 44:113-8. [PMID: 19961286 DOI: 10.3109/14017430903426902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVES Patients with aortic stenosis (AS) develop left ventricular remodeling characterized by changes in extracellular matrix (ECM) and cardiomyocyte-hypertrophy. Aortic valve replacement (AVR) reverses this process (reverse remodeling). We examined plasma levels of interleukin-18 (IL-18) and its binding protein (IL-18BP) before and after AVR for AS since these mediators have been shown experimentally to exert effects on myocardial remodeling. DESIGN Plasma levels of IL-18 and IL-18BP were analyzed in 22 patients with AS undergoing AVR, preoperatively, two days, six and 12 months postoperatively. Echocardiography and functional testing were performed. RESULTS IL-18BP was significantly increased by 28% and 15% at two days and six months after AVR, compared to preoperative values. In contrast, IL-18 showed a later peak (increased by 24% at 12 months postoperatively) when IL-18BP was normalized. IL-18 correlated positively with deceleration time (R = 0.44) at this time-point which might indicate an association with diastolic function. CONCLUSIONS We report for the first time that plasma IL-18 and IL-18BP are differentially regulated after AVR for AS with an early increase in IL-18BP postoperatively followed by a later peak in IL-18 at 12 months. Given the known effects of these mediators on myocardial remodeling and function, they might play a role in the reverse and remodeling process associated with AVR.
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Affiliation(s)
- Peter Majak
- Department of Cardiothoracic Surgery and Faculty of Medicine, University of Oslo, Oslo, Norway
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26
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Reddy VS, Harskamp RE, van Ginkel MW, Calhoon J, Baisden CE, Kim IS, Valente AJ, Chandrasekar B. Interleukin-18 stimulates fibronectin expression in primary human cardiac fibroblasts via PI3K-Akt-dependent NF-kappaB activation. J Cell Physiol 2008; 215:697-707. [PMID: 18064631 DOI: 10.1002/jcp.21348] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Fibronectin (FN), a key component of the extracellular matrix, is upregulated in cardiac tissue during myocardial hypertrophy and failure. Here we show that interleukin (IL)-18, a proinflammatory and pro-hypertrophic cytokine, stimulates FN expression in adult human cardiac fibroblasts (HCF), an effect blocked by either the IL-18BP:Fc chimera or IL-18 neutralizing antibodies. IL-18 stimulated FN promoter-reporter activity in HCF, a response attenuated by mutation of an NF-kappaB binding site in the FN promoter. Overexpression of p65 stimulated FN transcription. IL-18 stimulated in vitro (p65, p50) and in vivo NF-kappaB DNA binding activities, and induced kappaB-dependent reporter gene activity. These effects were inhibited by adenoviral transduction of dominant negative (dn) p65 (Ad.dnp65) and dnIKK2 (Ad.dnIKK2). Investigation of signaling intermediates revealed that IL-18 stimulated PI3 kinase activity (blocked by wortmannin, LY294002, or Ad.dnPI3Kp85), and Akt phosphorylation and kinase activity (blocked by SH-5 or Ad.dnAkt). Furthermore, targeting MyD88, IRAK1, TRAF6, PI3K, Akt, and NF-kappaB by RNA interference or dn expression vectors blunted IL-18 mediated FN transcription and mRNA expression. Conversely, FN stimulated IL-18 expression. These data provide the first evidence that IL-18 and FN stimulate each other's expression in HCF, and suggest a role for IL-18, FN and their crosstalk in myocardial hypertrophy and remodeling, disease states characterized by enhanced FN expression and fibrosis.
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27
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Bruggink AH, van Oosterhout MFM, de Jonge N, Cleutjens JPM, van Wichen DF, van Kuik J, Tilanus MGJ, Gmelig-Meyling FHJ, van den Tweel JG, de Weger RA. Type IV collagen degradation in the myocardial basement membrane after unloading of the failing heart by a left ventricular assist device. J Transl Med 2007; 87:1125-37. [PMID: 17876299 DOI: 10.1038/labinvest.3700670] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
After left ventricular assist device (LVAD) support in patients with end-stage cardiomyopathy, cardiomyocytes decrease in size. We hypothesized that during this process, known as reverse remodeling, the basement membrane (BM), which is closely connected to, and forms the interface between the cardiomyocytes and the extracellular matrix, will be severely affected. Therefore, the changes in the myocardial BM in patients with end-stage heart failure before and after LVAD support were studied. The role of MMP-2 in this process was also investigated. Transmission electron microscopy showed that the BM thickness decreased post-LVAD compared to pre-LVAD. Immunohistochemistry indicated a reduced immunoreactivity for type IV collagen in the BM after LVAD support. Quantitative PCR showed a similar mRNA expression for type IV collagen pre- and post-LVAD. MMP-2 mRNA almost doubled post-LVAD (P<0.01). In addition, active MMP-2 protein as identified by gelatin zymography and confirmed by Western blot analysis was detected after LVAD support and in controls, but not before LVAD support. Active MMP was localized in the BM of the cardiomyocyte, as detected by type IV collagen in situ zymography. Furthermore, in situ hybridization/immunohistochemical double staining showed that MMP-2 mRNA was expressed in cardiomyocytes, macrophages, T-cells and endothelial cells. Taken together, these findings show reduced type IV collagen content in the BM of cardiomyocytes after LVAD support. This reduction is at least in part the result of increased MMP-2 activity and not due to reduced synthesis of type IV collagen.
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Affiliation(s)
- Annette H Bruggink
- Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands.
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Fayet C, Bendeck MP, Gotlieb AI. Cardiac valve interstitial cells secrete fibronectin and form fibrillar adhesions in response to injury. Cardiovasc Pathol 2007; 16:203-11. [PMID: 17637428 DOI: 10.1016/j.carpath.2007.02.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2006] [Revised: 12/21/2006] [Accepted: 02/21/2007] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Fibronectin, an extracellular matrix protein, is associated with the general process of tissue repair and is present in heart valves. In order to understand the cellular mechanisms of heart valve repair, we hypothesized that fibronectin is produced and secreted by valvular interstitial cells (VICs), and when up-regulated in VICs involved in active repair, it is associated with prominent fibrillar adhesions composed of tensin and alpha(5)beta(1) integrin. We investigated the interaction of porcine mitral VICs with the underlying fibronectin matrix and the formation and localization of focal and fibrillar adhesion complexes in an in vitro wound model. METHODS Confluent monolayers of VICs were wounded with a 1-mm-wide cell scraper, maintained in standard media and 10% fetal bovine serum, and fixed at various time points after wounding. Immunohistochemistry was used to localize fibronectin, paxillin, tensin, and alpha(5)beta(1) integrin. F-actin was localized with an Alexa-Fluor-568-labeled phalloidin. Cells were examined with a scanning confocal laser microscope. RESULTS In response to in vitro mechanical wounding, migrating VICs at the wound edge expressed cytoplasmic fibronectin compared to nonwounded confluent monolayers. Over 24 to 48 h, fibrils were deposited into the subcellular space. Coincident with this, staining for alpha(5)beta(1) appeared, and tensin redistributed from focal adhesions to fibrillar adhesions, which colocalized with alpha(5)beta(1). CONCLUSIONS Fibronectin in association with fibrillar adhesions is a component of the matrix that may be secreted by migrating VICs to regulate repair at sites of valve injury.
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Affiliation(s)
- Cristina Fayet
- Toronto General Research Institute and Department of Pathology, University Health Network, Toronto, Ontario, Canada M5G 2C4
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29
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Jane-Lise S, Corda S, Chassagne C, Rappaport L. The extracellular matrix and the cytoskeleton in heart hypertrophy and failure. Heart Fail Rev 2005; 5:239-50. [PMID: 16228907 DOI: 10.1023/a:1009857403356] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Cell characteristics and phenotype depend on the nature of the extracellular matrix, the type and organization of integrins and cytoskeleton. The interactions between these components are poorly known at the myocyte level and during cardiac remodeling associated with cardiac hypertrophy and heart failure. We analyze here the nature and organization of extracellular matrix (ECM) proteins, cytoskeleton and integrins and their regulation by growth factors, such as angiotensin II, in normal myocyte growth and in pathological growth (hypertrophy) of the myocardium and heart failure.
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30
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Affiliation(s)
- Shaw-Yung Shai
- Departments of Physiology, Medicine, Cardiovascular Research Laboratories, UCLA School of Medicine, Los Angeles, CA 90095, USA
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31
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Lyons AJ, Bateman AC, Spedding A, Primrose JN, Mandel U. Oncofetal fibronectin and oral squamous cell carcinoma. Br J Oral Maxillofac Surg 2001; 39:471-7. [PMID: 11735145 DOI: 10.1054/bjom.2001.0702] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Fibronectin is a cell matrix glycoprotein, which exists as a number of isoforms that are often found within the cell matrix that surrounds tumours. Collectively these tumour-associated isomers of fibronectin have been termed oncofetal fibronectin (OFFN). We looked for expression of OFFN within oral squamous cell carcinomas (SCC) and related its presence to prognosis. The investigation used a monoclonal antibody (MoAb 5C10) to the glycosylated variant of OFFN, and 100 archival specimens of oral SSC. Immunostaining for OFFN was intense in the adjacent stroma of 43 squamous carcinomas, weak in 27 and absent in 30. Cervical metastases were found in 17/27 (63%) specimens that stained intensely, 6/17 (35%) that stained weakly and 3/13 (23%) that did not stain. Of the 21 cases which had extracapsular lymph node spread, 81% were from those that stained intensely, 19% from those that stained weakly and none from those that did not stain for OFFN expression. Also, 21/44 patients (49%) died in group with intense OFFN staining, 6/26 (23%) in the group with weak staining and 3/30 (10%) in the group that did not stain. The presence of OFFN glycoprotein in oral SCC as evaluated by immunostaining with MoAb 5C10 correlates strongly with the presence of metastatic lymph node involvement, particularly extracapsular involvement, and mortality. We therefore suggest that the degree of expression of OFFN in tumours is a valuable prognostic indicator.
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Affiliation(s)
- A J Lyons
- Department of Oral and Maxillofacial Surgery, King's College Hospital, Caldecor Road, London SE5 9RW, UK.
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32
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Abstract
Extracellular matrix provides a structural, chemical, and mechanical substrate that is essential in cardiac development, growth, and responses to pathophysiological signals. Transmembrane receptors termed integrins provide a dynamic interaction of environmental cues and intracellular events. Integrins orchestrate multiple functions in the intact organism including organogenesis, regulation of gene expression, cell proliferation, differentiation, migration, and death. They are expressed in all cellular components of the cardiovascular system, including the vasculature, blood, cardiac myocytes and nonmuscle cardiac cells. The focus of this review will be on the role of integrins in the myocardium. We will provide background on integrin structure and function, discuss how the expression of integrins is critical to the form and function of the developing and postnatal myocardium, and review the known data on integrins as signaling molecules in the heart. Finally, we will offer insights to the future research directions into this important family of extracellular matrix receptors in the myocardium.
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Affiliation(s)
- R S Ross
- Department of Physiology, The Cardiovascular Research Laboratories, UCLA School of Medicine, Los Angeles, CA 90095-1751, USA.
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33
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Abro E, Griffiths CD, Morgan TO, Delbridge LMD. Regression of cardiac hypertrophy in the SHR by combined renin-angiotensin system blockade and dietary sodium restriction. J Renin Angiotensin Aldosterone Syst 2001; 2:S148-S153. [DOI: 10.1177/14703203010020012601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Altered operation of the renin-angiotensin-aldosterone system (RAAS) and dietary sodium intake have been identified as independent risk factors for cardiac hypertrophy. The way in which sodium intake and the operation of the renin-angiotensin-aldosterone system interact in the pathogenesis of cardiac hypertrophy is poorly understood. The aims of this study were to investigate the cardiac effects of the renin-angiotensin system (RAS) blockade in the spontaneously hypertensive rat (SHR), using co-treatment with an angiotensin II receptor blocker (ARB) and an angiotensin-converting enzyme (ACE) inhibitor with different sodium intakes. Our experiments with SHR show that, at high levels of sodium intake (4.0%), aggressive RAS blockade treatment with candesartan (3 mg/kg) and perindopril (6 mg/kg) does not result in regression of cardiac hypertrophy. In contrast, RAS blockade coupled with reduced sodium diet (0.2%) significantly regresses cardiac hypertrophy, impairs animal growth and is associated with elevated plasma renin and dramatically suppressed plasma angiotensinogen levels. Histological analyses indicate that the differential effect of reduced sodium on heart growth during RAS blockade is not associated with any change in myocardial interstitial collagen, but reflects modification of cellular geometry. Dimensional measurements of enzymatically-isolated ventricular myocytes show that, in the RAS blocked, reduced sodium group, myocyte length and width were decreased by about 16—19% compared with myocytes from the high sodium treatment group. Our findings highlight the importance of `titrating' sodium intake with combined RAS blockade in the clinical setting to optimise therapeutic benefit.
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Affiliation(s)
- Emad Abro
- Department of Physiology, University of Melbourne, Parkville,
Victoria, 3010, Australia
| | - Cory D Griffiths
- Department of Physiology, University of Melbourne, Parkville,
Victoria, 3010, Australia
| | - Trefor O Morgan
- Department of Physiology, University of Melbourne, Parkville,
Victoria, 3010, Australia
| | - Lea MD Delbridge
- Department of Physiology, University of Melbourne, Parkville,
Victoria, 3010, Australia,
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34
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Grimm D, Huber M, Jabusch HC, Shakibaei M, Fredersdorf S, Paul M, Riegger GA, Kromer EP. Extracellular matrix proteins in cardiac fibroblasts derived from rat hearts with chronic pressure overload: effects of beta-receptor blockade. J Mol Cell Cardiol 2001; 33:487-501. [PMID: 11181017 DOI: 10.1006/jmcc.2000.1321] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Left ventricular hypertrophy (LVH) is accompanied by progressive accumulations of extracellular matrix proteins. They are produced predominantly by cardiac fibroblasts that surround the cardiac myocytes. The aim of this study was to emphasize the role of a combined approach using both in vivo and in vitro studies to elucidate the effects of carvedilol on cardiac remodeling. We therefore used an established model of supravalvular aortic banding and cardiac fibroblasts. LVH was induced by banding of the ascending aorta. Male Wistar rats were allocated to four groups: sham-operated, sham+carvedilol, aortic stenosis (AS), and AS+carvedilol. Treatment time was four weeks. Fibroblasts were isolated from the entire left ventricle of sham and AS rats. Carvedilol/metoprolol/prazosin were added (0.1, 1.0 and 10 microM; 24 h). In addition, interferon- gamma was applied for 24 h (10, 100 and 1000 IU). AS rats revealed increased LV weights (+27%) and cardiomyocyte widths as compared to sham-operated rats (1.6-fold, P<0.01). Carvedilol reduced LVH by 20%. This finding was accompanied by a decrease of laminin, fibronectin, collagen I and III in vivo. Collagen I/III and fibronectin were increased in fibroblasts of AS v sham rats (P<0.0001, each). Carvedilol reduced collagen I, III and fibronectin by 40/60/35% (0.1 microM; P<0.001) irrespective of LVH. Carvedilol had no effects on collagen IV and laminin. Carvedilol dose-dependently reduced the proliferation rate by 20% at 0.1 microM(P<0.0001). Metoprolol and prazosin had no effect on the expression of extracellular matrix proteins and on the proliferation of the cells of either origin. Interferon- gamma blunted the proliferation rate of cultured fibroblasts and lead to a significant decrease in extracellular matrix deposits. These results indicate that the effects of carvedilol may be due to the antiproliferative or antioxidative properties of this unselective beta-adrenergic receptor antagonist. These changes of the extracellular matrix represent a new mechanism of carvedilol that may contribute to the observed beneficial effects in congestive heart failure.
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Affiliation(s)
- D Grimm
- Institut für Klinische Pharmakologie und Toxikologie, Benjamin Franklin Medical Center, Freie Universität Berlin, Garystr. 5, D-14195 Berlin, Germany.
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35
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Affiliation(s)
- S Hein
- Kerckhoff Clinic, Department of Cardiac Surgery, Bad Nauheim, Germany.
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36
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Keller RS, Shai SY, Babbitt CJ, Pham CG, Solaro RJ, Valencik ML, Loftus JC, Ross RS. Disruption of integrin function in the murine myocardium leads to perinatal lethality, fibrosis, and abnormal cardiac performance. THE AMERICAN JOURNAL OF PATHOLOGY 2001; 158:1079-90. [PMID: 11238056 PMCID: PMC1850360 DOI: 10.1016/s0002-9440(10)64055-2] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The molecular mechanisms that regulate the cardiac hypertrophic response and the progression from compensated hypertrophy to decompensated heart failure have not been thoroughly defined. Alteration in cardiac extracellular matrix is a distinguishing characteristic of these pathological processes. Integrins, cell surface receptors that mediate cellular adhesion to the extracellular matrix, are signaling molecules that possess mechanotransduction properties. Therefore, we hypothesized that integrins are likely candidates to play an important role in cardiac function. To test this hypothesis, transgenic mice were constructed in which normal integrin function was disrupted by expression of a chimeric molecule encoding the transmembrane and extracellular domains of the Tac subunit of the IL-2 receptor, fused to the cytoplasmic domain of beta(1A) integrin (Tacbeta(1A)). Using the alpha myosin heavy chain promoter to target expression of this chimera to the cardiac myocyte, transgenic mice were generated that had varied levels of transgene expression. Multiple transgenic founders that expressed the transgene at high levels, died perinatally and exhibited replacement fibrosis. Lines that survived showed 1) hypertrophic changes concordant with reduction in endogenous beta(1) integrin levels, or 2) reduced basal contractility and relaxation as well as alterations in components of integrin signaling pathways. These data support an important role for beta(1) integrin in normal cardiac function.
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Affiliation(s)
- R S Keller
- Department of Physiology, UCLA School of Medicine, Center for the Health Sciences, Los Angeles, CA 90095-1751, USA
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37
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Pham CG, Harpf AE, Keller RS, Vu HT, Shai SY, Loftus JC, Ross RS. Striated muscle-specific beta(1D)-integrin and FAK are involved in cardiac myocyte hypertrophic response pathway. Am J Physiol Heart Circ Physiol 2000; 279:H2916-26. [PMID: 11087248 DOI: 10.1152/ajpheart.2000.279.6.h2916] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Alterations in the extracellular matrix occur during the cardiac hypertrophic process. Because integrins mediate cell-matrix adhesion and beta(1D)-integrin (beta1D) is expressed exclusively in cardiac and skeletal muscle, we hypothesized that beta1D and focal adhesion kinase (FAK), a proximal integrin-signaling molecule, are involved in cardiac growth. With the use of cultured ventricular myocytes and myocardial tissue, we found the following: 1) beta1D protein expression was upregulated perinatally; 2) alpha(1)-adrenergic stimulation of cardiac myocytes increased beta1D protein levels 350% and altered its cellular distribution; 3) adenovirally mediated overexpression of beta1D stimulated cellular reorganization, increased cell size by 250%, and induced molecular markers of the hypertrophic response; and 4) overexpression of free beta1D cytoplasmic domains inhibited alpha(1)-adrenergic cellular organization and atrial natriuretic factor (ANF) expression. Additionally, FAK was linked to the hypertrophic response as follows: 1) coimmunoprecipitation of beta1D and FAK was detected; 2) FAK overexpression induced ANF-luciferase; 3) rapid and sustained phosphorylation of FAK was induced by alpha(1)-adrenergic stimulation; and 4) blunting of the alpha(1)-adrenergically modulated hypertrophic response was caused by FAK mutants, which alter Grb2 or Src binding, as well as by FAK-related nonkinase, a dominant interfering FAK mutant. We conclude that beta1D and FAK are both components of the hypertrophic response pathway of cardiac myocytes.
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Affiliation(s)
- C G Pham
- Departments of Physiology and Medicine and Cardiovascular Research Laboratories, University of California School of Medicine, Los Angeles, California 90095, USA
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38
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Inaba M, Fushiki S, Yaoi T, Iwata T, Kamoi K, Okihara K, Ukimura O, Kawauchi A, Miyashita H, Kojima M, Miki T. Changes in Extracellular Matrix Components of Bladder Detrusor in Relation to Bladder Hypertrophy and Compliance in Patients with Benign Prostatic Hyperplasia. Acta Histochem Cytochem 2000. [DOI: 10.1267/ahc.33.131] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Mitsuhiko Inaba
- Department of Urology,Research Institute for Neurological Diseases and Geriatrics,Kyoto Prefectural University of Medicine,Kawaramachi Hirokoji,Kamigyo-ku,Kyoto 602-8566
- Department of Dynamic Pathology,Research Institute for Neurological Diseases and Geriatrics,Kyoto Prefectural University of Medicine,Kawaramachi Hirokoji,Kamigyo-ku,Kyoto 602-8566
| | - Shinji Fushiki
- Department of Dynamic Pathology,Research Institute for Neurological Diseases and Geriatrics,Kyoto Prefectural University of Medicine,Kawaramachi Hirokoji,Kamigyo-ku,Kyoto 602-8566
| | - Takeshi Yaoi
- Department of Dynamic Pathology,Research Institute for Neurological Diseases and Geriatrics,Kyoto Prefectural University of Medicine,Kawaramachi Hirokoji,Kamigyo-ku,Kyoto 602-8566
| | - Tsuyoshi Iwata
- Department of Urology,Research Institute for Neurological Diseases and Geriatrics,Kyoto Prefectural University of Medicine,Kawaramachi Hirokoji,Kamigyo-ku,Kyoto 602-8566
| | - Kazumi Kamoi
- Department of Urology,Research Institute for Neurological Diseases and Geriatrics,Kyoto Prefectural University of Medicine,Kawaramachi Hirokoji,Kamigyo-ku,Kyoto 602-8566
| | - Koji Okihara
- Department of Urology,Research Institute for Neurological Diseases and Geriatrics,Kyoto Prefectural University of Medicine,Kawaramachi Hirokoji,Kamigyo-ku,Kyoto 602-8566
| | - Osamu Ukimura
- Department of Urology,Research Institute for Neurological Diseases and Geriatrics,Kyoto Prefectural University of Medicine,Kawaramachi Hirokoji,Kamigyo-ku,Kyoto 602-8566
| | - Akihiro Kawauchi
- Department of Urology,Research Institute for Neurological Diseases and Geriatrics,Kyoto Prefectural University of Medicine,Kawaramachi Hirokoji,Kamigyo-ku,Kyoto 602-8566
| | - Hiroaki Miyashita
- Department of Urology,Research Institute for Neurological Diseases and Geriatrics,Kyoto Prefectural University of Medicine,Kawaramachi Hirokoji,Kamigyo-ku,Kyoto 602-8566
| | - Munekado Kojima
- Department of Urology,Research Institute for Neurological Diseases and Geriatrics,Kyoto Prefectural University of Medicine,Kawaramachi Hirokoji,Kamigyo-ku,Kyoto 602-8566
| | - Tsuneharu Miki
- Department of Urology,Research Institute for Neurological Diseases and Geriatrics,Kyoto Prefectural University of Medicine,Kawaramachi Hirokoji,Kamigyo-ku,Kyoto 602-8566
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39
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Grimm D, Holmer SR, Riegger GA, Kromer EP. Effects of beta-receptor blockade and angiotensin II type I receptor antagonism in isoproterenol-induced heart failure in the rat. Cardiovasc Pathol 1999; 8:315-23. [PMID: 10615017 DOI: 10.1016/s1054-8807(99)00021-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
The aim of this study was to examine the effects of both angiotensin II type I receptor antagonism using losartan (LOS) and beta-receptor blockade by metoprolol (MP) in isoproterenol-induced cardiac injury in the rat. Two weeks after isoproterenol (ISO) application, 90 ISO and 30 control (CTRL) rats were examined. ISO rats were treated for two weeks with either LOS, MP, or vehicle (n = 30 each group). Compared to CTRL, ISO induced left ventricular hypertrophy (LVH), fibrosis, and overexpression of extracellular matrix proteins. LOS significantly attenuated these changes. MP only reduced LVH, but exerted no effect on structural alterations. LV end-diastolic and mean right atrial pressures were significantly increased in the ISO group and normalized in the LOS and MP group. Mean aortic blood flow velocity was significantly decreased in the ISO group and unaltered in the LOS and MP group versus CTRL. Blood pressure was decreased in ISO and LOS rats. MP treatment had no effect on blood pressure, but significantly lowered heart rate. Isoproterenol induced mild heart failure. Losartan and metoprolol applications in ISO-treated rats were highly effective in attenuating hemodynamic alterations and LVH. Early application of losartan 24 hours after isoproterenol-induced cardiac injury revealed significant beneficial effects on myocardial structure.
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MESH Headings
- Adrenergic beta-Agonists/pharmacology
- Angiotensin Receptor Antagonists
- Animals
- Extracellular Matrix Proteins/chemistry
- Extracellular Matrix Proteins/drug effects
- Female
- Fluorescent Antibody Technique, Indirect
- Heart/drug effects
- Heart/physiopathology
- Heart Failure/chemically induced
- Heart Failure/metabolism
- Heart Failure/pathology
- Heart Failure/prevention & control
- Heart Ventricles/drug effects
- Heart Ventricles/pathology
- Hemodynamics/drug effects
- Hypertrophy, Left Ventricular/chemically induced
- Hypertrophy, Left Ventricular/metabolism
- Hypertrophy, Left Ventricular/pathology
- Hypertrophy, Left Ventricular/prevention & control
- Immunoenzyme Techniques
- Isoproterenol/toxicity
- Laminin/metabolism
- Losartan/pharmacology
- Metoprolol/pharmacology
- Organ Size/drug effects
- Rats
- Rats, Sprague-Dawley
- Receptor, Angiotensin, Type 1
- Receptor, Angiotensin, Type 2
- Receptors, Adrenergic, beta/physiology
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Affiliation(s)
- D Grimm
- Institute of Clinical Pharmacology and Toxicology, UKBF FU Berlin, Germany.
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40
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Peters TH, Sharma HS, Yilmaz E, Bogers AJ. Quantitative analysis of collagens and fibronectin expression in human right ventricular hypertrophy. Ann N Y Acad Sci 1999; 874:278-85. [PMID: 10415539 DOI: 10.1111/j.1749-6632.1999.tb09243.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
One of the main features in human tetralogy of Fallot (TF) is right ventricular hypertrophy (RVH) due to pressure (sub-pulmonary stenosis) and volume overload (ventricular septal defect). Currently, primary correction at a young age is the treatment of choice. To unravel the role of extracellular matrix in RVH, we examined myocardial expression of collagens and fibronectin in TF patients with primary correction (TF1, age 0.7 +/- 0.2 yr.), secondary surgery (TF2, age 36.9 +/- 4.6 yr), and in age-matched control patients. Sirius red staining quantified by video imaging showed significantly increased interstitial staining for collagens in both TF1 and TF2 groups as compared to respective controls. Fibronectin was expressed in extracellular spaces, perivascular regions, and in some cardiomyocytes. Quantitative analysis of fibronectin revealed increased expression in only TF1 group as compared to respective control. Our results indicate an increased amount of myocardial extracellular matrix deposition as a sign of fibrosis during RVH in patients with TF.
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Affiliation(s)
- T H Peters
- Erasmus University Medical Center, Rotterdam, The Netherlands
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41
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Hocevar BA, Brown TL, Howe PH. TGF-beta induces fibronectin synthesis through a c-Jun N-terminal kinase-dependent, Smad4-independent pathway. EMBO J 1999; 18:1345-56. [PMID: 10064600 PMCID: PMC1171224 DOI: 10.1093/emboj/18.5.1345] [Citation(s) in RCA: 526] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Transforming growth factor-beta (TGF-beta) exerts its effects on cell proliferation, differentiation and migration in part through its modulation of extracellular matrix components, such as fibronectin and plasminogen activator inhibitor-1 (PAI-1). Although the SMAD family of proteins recently has been shown to be a key participant in TGF-beta signaling, other signaling pathways have also been shown to be activated by TGF-beta. We report here that c-Jun N-terminal kinase (JNK), a member of the MAP kinase family, is activated in response to TGF-beta in the human fibrosarcoma HT1080-derived cell line BAHgpt. Stable expression of dominant-negative forms of JNK1 and MKK4, an upstream activator of JNK, results in loss of TGF-beta-stimulated fibronectin mRNA and protein induction, while having little effect on TGF-beta-induced levels of PAI-1. The human fibronectin promoter contains three CRE elements, one of which has been shown to bind a c-Jun-ATF-2 heterodimer. Utilizing a GAL4 fusion trans-reporting system, we demonstrate a decrease in transactivating potential of GAL4-c-Jun and GAL4-ATF-2 in dominant-negative JNK1- and MKK4-expressing cells. Finally, we show that TGF-beta-induced fibronectin synthesis is independent of Smad4. These results demonstrate that TGF-beta-mediated fibronectin induction requires activation of JNK which in turn modulates the activity of c-Jun and ATF-2 in a Smad4independent manner.
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Affiliation(s)
- B A Hocevar
- Department of Cell Biology, The Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
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42
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Kim H, Yoon CS, Kim H, Rah B. Expression of extracellular matrix components fibronectin and laminin in the human fetal heart. Cell Struct Funct 1999; 24:19-26. [PMID: 10355875 DOI: 10.1247/csf.24.19] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
It has been well documented that the extracellular matrix components fibronectin and laminin promote or regulate morphogenesis of the myocardial cells in mammalian heart. However, their chronological change of expression (or localization) in the human heart remains elusive. In this study, fibronectin and laminin in the left ventricle of forty-two human fetuses aged from 8 to 26 weeks gestation and left ventricular tissues obtained from a 2-week old infant and two adults were investigated by Western blot analyses and indirect immunofluorescence technique with monoclonal antibodies. In the fetal heart, fibronectins were present along the endocardium, epicardium, and linings of larger blood vessels. In 14-16 weeks gestation, fibronectin immunofluorescence became stronger but not evenly dispersed in the interstitium. After 24 weeks gestation, they were strongly positive only in the relatively larger blood vessels, as well as those in the infant and adult cardiac tissues. Laminins were strongly positive along the endocardium and basement membrane of the myocardial cells and fibroblasts during fetal life. After birth, laminins formed fine fibrillar network along the basement membrane in association with the transverse tubules of myocardial cell; these morphological characteristics remained in the adult cardiac tissues. These results indicate that fibronectin expression is relatively constant during fetal life but decreases after birth; in contrast, laminin expression is not age-dependent and constant throughout the life.
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Affiliation(s)
- H Kim
- Department of Histology, College of Medicine, Chung-Ang University, Seoul, Korea (South).
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43
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Kuga T, Esato K, Zempo N, Fujioka K, Nakamura K. Detection of type III collagen fragments in specimens of abdominal aortic aneurysms. Surg Today 1998; 28:385-90. [PMID: 9590702 DOI: 10.1007/s005950050146] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The purpose of this study was to analyze the collagens in aortic aneurysm walls and to investigate the mechanism of the formation of calcified abdominal aortic aneurysms (AAAs). Collagens were extracted from human aneurysmal aortic walls obtained during surgery, and from human nonaneurysmal aortic walls obtained at autopsy, using pepsin-acetic acid digestion. Electrophoresis and immunoblotting were performed. Type III collagen was found to be reduced in the arteriosclerotic aneurysmal aortic walls. The alpha1 chain of type II collagen/alpha1 chain of type I collagen ratio was 0.35+/-0.11 in the aortic aneurysms and 0.68+/-0.11 in the nonaneurysmal aortic walls (P=0.0111). All the calcified aneurysms were associated with type III collagen fragments having molecular mass of approximately 70 kDa and 30 kDa as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Thus, we concluded that AAAs with calcification may be caused by an abnormal degradation of type III collagen.
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Affiliation(s)
- T Kuga
- First Department of Surgery, Yamaguchi University School of Medicine, Ube, Japan
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Lee AA, McCulloch AD. Multiaxial myocardial mechanics and extracellular matrix remodeling: mechanochemical regulation of cardiac fibroblast function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1997; 430:227-40. [PMID: 9330732 DOI: 10.1007/978-1-4615-5959-7_19] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Substantial evidence suggests that not only does the structure of the cardiac extracellular matrix affect the mechanical properties of myocardium, but that mechanical loading affects the synthesis of the extracellular matrix. However, loading conditions in vivo are nonhomogeneous and multiaxial. An experimental approach that combines mechanics and cell biology is used to examine the mechanisms of extracellular matrix remodeling in the heart. The results indicate that differential biological responses in adult cardiac fibroblasts can be correlated with specific physical signals, such as the magnitude and two dimensional (2D) pattern of strain. Some effects of flow-function relations are discussed.
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Affiliation(s)
- A A Lee
- Department of Bioengineering, University of California San Diego, La Jolla, USA
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Sabri A, Levy BI, Poitevin P, Caputo L, Faggin E, Marotte F, Rappaport L, Samuel JL. Differential roles of AT1 and AT2 receptor subtypes in vascular trophic and phenotypic changes in response to stimulation with angiotensin II. Arterioscler Thromb Vasc Biol 1997; 17:257-64. [PMID: 9081679 DOI: 10.1161/01.atv.17.2.257] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The aim of this study was to investigate the roles of angiotensin II (Ang II) receptor subtypes 1 (AT1) and 2 (AT2) in producing vascular wall hypertrophy and qualitative changes in smooth muscle cell gene expression. Wistar rats were treated for 23 days with osmotic minipumps containing solvent and either Ang II (120 ng.kg-1.min-1) or PD123319 (30 mg.kg-1.d-1), an AT2 receptor antagonist. In addition, rats receiving solvent and either Ang II or PD123319 were given losartan, an AT1 receptor antagonist, in the drinking water (10 mg.kg-1.d-1). Vascular wall hypertrophy and smooth muscle phenotype were characterized by morphometric analysis combined with immunohistochemistry. Ang II-induced hypertension was associated with the development of medial hypertrophy of the aorta and coronary arteries accompanied by reversion of vascular smooth muscle cells (VSMCs) toward an immature phenotype, as shown by the expression of cellular fibronectin and nonmuscle myosin. Losartan treatment, which restored normal arterial pressure, prevented all these changes. PD123319 treatment, which had no effect on blood pressure, prevented only vascular hypertrophy, with no effect on VSMC phenotype. Administration of only losartan to normal rats reproduced the Ang II-induced vascular hypertrophy, with no effect on VSMC phenotype. Taken together, these results suggest that (1) the trophic effect of Ang II on VSMCs is mediated via AT2 receptor subtypes and (2) changes in VSMC phenotypes are triggered mainly through AT1 receptor subtypes.
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Affiliation(s)
- A Sabri
- U127 INSERM, Université D. Diderot, Paris, France
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