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Bodmer NK, Knutsen RH, Roth RA, Castile RM, Brodt MD, Gierasch CM, Broekelmann TJ, Gibson MA, Haspel JA, Lake SP, Brody SL, Silva MJ, Mecham RP, Ornitz DM. Multi-organ phenotypes in mice lacking latent TGFβ binding protein 2 (LTBP2). Dev Dyn 2024; 253:233-254. [PMID: 37688792 PMCID: PMC10842386 DOI: 10.1002/dvdy.651] [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: 05/25/2023] [Revised: 08/02/2023] [Accepted: 08/09/2023] [Indexed: 09/11/2023] Open
Abstract
BACKGROUND Latent TGFβ binding protein-2 (LTBP2) is a fibrillin 1 binding component of the microfibril. LTBP2 is the only LTBP protein that does not bind any isoforms of TGFβ, although it may interfere with the function of other LTBPs or interact with other signaling pathways. RESULTS Here, we investigate mice lacking Ltbp2 (Ltbp2-/- ) and identify multiple phenotypes that impact bodyweight and fat mass, and affect bone and skin development. The alterations in skin and bone development are particularly noteworthy since the strength of these tissues is differentially affected by loss of Ltbp2. Interestingly, some tissues that express high levels of Ltbp2, such as the aorta and lung, do not have a developmental or homeostatic phenotype. CONCLUSIONS Analysis of these mice show that LTBP2 has complex effects on development through direct effects on the extracellular matrix (ECM) or on signaling pathways that are known to regulate the ECM.
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Affiliation(s)
- Nicholas K. Bodmer
- Department of Developmental Biology, Washington University School of Medicine
- Department of Cell Biology and Physiology, Washington University School of Medicine
| | - Russell H. Knutsen
- Department of Cell Biology and Physiology, Washington University School of Medicine
| | - Robyn A. Roth
- Department of Cell Biology and Physiology, Washington University School of Medicine
| | - Ryan M. Castile
- Department of Mechanical Engineering and Materials Science, Washington University School of Engineering
| | - Michael D. Brodt
- Department of Orthopedic Surgery, Washington University School of Medicine, St Louis, MO, USA
| | - Carrie M. Gierasch
- Division of Pulmonary & Critical Care Medicine, Department of Medicine, Washington University School of Medicine
| | | | - Mark A. Gibson
- Discipline of Anatomy and Pathology, School of Medicine, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Jeffrey A. Haspel
- Division of Pulmonary & Critical Care Medicine, Department of Medicine, Washington University School of Medicine
| | - Spencer P. Lake
- Department of Mechanical Engineering and Materials Science, Washington University School of Engineering
| | - Steven L. Brody
- Division of Pulmonary & Critical Care Medicine, Department of Medicine, Washington University School of Medicine
| | - Matthew J. Silva
- Department of Orthopedic Surgery, Washington University School of Medicine, St Louis, MO, USA
| | - Robert P. Mecham
- Department of Cell Biology and Physiology, Washington University School of Medicine
| | - David M. Ornitz
- Department of Developmental Biology, Washington University School of Medicine
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2
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Su CT, See DHW, Huang YJ, Jao TM, Liu SY, Chou CY, Lai CF, Lin WC, Wang CY, Huang JW, Hung KY. LTBP4 Protects Against Renal Fibrosis via Mitochondrial and Vascular Impacts. Circ Res 2023; 133:71-85. [PMID: 37232163 DOI: 10.1161/circresaha.123.322494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 05/04/2023] [Indexed: 05/27/2023]
Abstract
BACKGROUND As a part of natural disease progression, acute kidney injury (AKI) can develop into chronic kidney disease via renal fibrosis and inflammation. LTBP4 (latent transforming growth factor beta binding protein 4) regulates transforming growth factor beta, which plays a role in renal fibrosis pathogenesis. We previously investigated the role of LTBP4 in chronic kidney disease. Here, we examined the role of LTBP4 in AKI. METHODS LTBP4 expression was evaluated in human renal tissues, obtained from healthy individuals and patients with AKI, using immunohistochemistry. LTBP4 was knocked down in both C57BL/6 mice and human renal proximal tubular cell line HK-2. AKI was induced in mice and HK-2 cells using ischemia-reperfusion injury and hypoxia, respectively. Mitochondrial division inhibitor 1, an inhibitor of DRP1 (dynamin-related protein 1), was used to reduce mitochondrial fragmentation. Gene and protein expression were then examined to assess inflammation and fibrosis. The results of bioenergetic studies for mitochondrial function, oxidative stress, and angiogenesis were assessed. RESULTS LTBP4 expression was upregulated in the renal tissues of patients with AKI. Ltbp4-knockdown mice showed increased renal tissue injury and mitochondrial fragmentation after ischemia-reperfusion injury, as well as increased inflammation, oxidative stress, and fibrosis, and decreased angiogenesis. in vitro studies using HK-2 cells revealed similar results. The energy profiles of Ltbp4-deficient mice and LTBP4-deficient HK-2 cells indicated decreased ATP production. LTBP4-deficient HK-2 cells exhibited decreased mitochondrial respiration and glycolysis. Human aortic endothelial cells and human umbilical vein endothelial cells exhibited decreased angiogenesis when treated with LTBP4-knockdown conditioned media. Mitochondrial division inhibitor 1 treatment ameliorated inflammation, oxidative stress, and fibrosis in mice and decreased inflammation and oxidative stress in HK-2 cells. CONCLUSIONS Our study is the first to demonstrate that LTBP4 deficiency increases AKI severity, consequently leading to chronic kidney disease. Potential therapies focusing on LTBP4-associated angiogenesis and LTBP4-regulated DRP1-dependent mitochondrial division are relevant to renal injury.
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Affiliation(s)
- Chi-Ting Su
- Department of Medicine, National Taiwan University Cancer Center Hospital, Taipei (C.-T.S., D.H.W.S., Y.-J.H.)
- National Taiwan University College of Medicine, Taipei (C.-T.S., D.H.W.S., C.-Y.C., C.-F.L., W.-C.L., C.-Y.W., J.-W.H., K.-Y.H.)
| | - Daniel H W See
- Department of Medicine, National Taiwan University Cancer Center Hospital, Taipei (C.-T.S., D.H.W.S., Y.-J.H.)
- National Taiwan University College of Medicine, Taipei (C.-T.S., D.H.W.S., C.-Y.C., C.-F.L., W.-C.L., C.-Y.W., J.-W.H., K.-Y.H.)
| | - Yue-Jhu Huang
- Department of Medicine, National Taiwan University Cancer Center Hospital, Taipei (C.-T.S., D.H.W.S., Y.-J.H.)
| | - Tzu-Ming Jao
- Global Innovation Joint-Degree Program International Joint Degree Master's Program in Agro-Biomedical Science in Food and Health, College of Medicine, National Taiwan University, Taipei (T.-M.J.)
| | - Shin-Yun Liu
- Liver Disease Prevention and Treatment Research Foundation, Taipei, Taiwan (S.-Y.L.)
| | - Chih-Yi Chou
- National Taiwan University College of Medicine, Taipei (C.-T.S., D.H.W.S., C.-Y.C., C.-F.L., W.-C.L., C.-Y.W., J.-W.H., K.-Y.H.)
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, National Taiwan University Hospital, National Taiwan University, Taipei (C.-Y.W.)
| | - Chun-Fu Lai
- National Taiwan University College of Medicine, Taipei (C.-T.S., D.H.W.S., C.-Y.C., C.-F.L., W.-C.L., C.-Y.W., J.-W.H., K.-Y.H.)
- Renal Division, Department of Internal Medicine (C.-F.L.), National Taiwan University Hospital, Taipei
| | - Wei-Chou Lin
- Department of Pathology (W.-C.L.), National Taiwan University Hospital, Taipei
| | - Chih-Yuan Wang
- National Taiwan University College of Medicine, Taipei (C.-T.S., D.H.W.S., C.-Y.C., C.-F.L., W.-C.L., C.-Y.W., J.-W.H., K.-Y.H.)
| | - Jenq-Wen Huang
- National Taiwan University College of Medicine, Taipei (C.-T.S., D.H.W.S., C.-Y.C., C.-F.L., W.-C.L., C.-Y.W., J.-W.H., K.-Y.H.)
- Renal Division, Department of Internal Medicine, National Taiwan University Yunlin Branch, Douliu (J.-W.H.)
| | - Kuan-Yu Hung
- National Taiwan University College of Medicine, Taipei (C.-T.S., D.H.W.S., C.-Y.C., C.-F.L., W.-C.L., C.-Y.W., J.-W.H., K.-Y.H.)
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3
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Zhang X, Alanazi YF, Jowitt TA, Roseman AM, Baldock C. Elastic Fibre Proteins in Elastogenesis and Wound Healing. Int J Mol Sci 2022; 23:4087. [PMID: 35456902 PMCID: PMC9027394 DOI: 10.3390/ijms23084087] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/31/2022] [Accepted: 04/03/2022] [Indexed: 12/30/2022] Open
Abstract
As essential components of our connective tissues, elastic fibres give tissues such as major blood vessels, skin and the lungs their elasticity. Their formation is complex and co-ordinately regulated by multiple factors. In this review, we describe key players in elastogenesis: fibrillin-1, tropoelastin, latent TGFβ binding protein-4, and fibulin-4 and -5. We summarise their roles in elastogenesis, discuss the effect of their mutations on relevant diseases, and describe their interactions involved in forming the elastic fibre network. Moreover, we look into their roles in wound repair for a better understanding of their potential application in tissue regeneration.
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Affiliation(s)
- Xinyang Zhang
- Wellcome Centre for Cell-Matrix Research, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK; (X.Z.); (T.A.J.)
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK;
| | - Yasmene F. Alanazi
- Department of Biochemistry, Faculty of Science, University of Tabuk, Tabuk 71491, Saudi Arabia;
| | - Thomas A. Jowitt
- Wellcome Centre for Cell-Matrix Research, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK; (X.Z.); (T.A.J.)
| | - Alan M. Roseman
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK;
| | - Clair Baldock
- Wellcome Centre for Cell-Matrix Research, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK; (X.Z.); (T.A.J.)
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK;
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4
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Barnes NM, Wu H. Mechanisms regulating the airborne survival of Klebsiella pneumoniae under different relative humidity and temperature levels. INDOOR AIR 2022; 32:e12991. [PMID: 35225398 DOI: 10.1111/ina.12991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 12/23/2021] [Accepted: 01/20/2022] [Indexed: 06/14/2023]
Abstract
In this study, Klebsiella pneumoniae was suspended in synthetic saliva in a nebulizer (N0 ) and nebulized for 5 min (N5 ) into an aerosol chamber and further prolonged in the aerosolization phase for 15 min (A15 ) under four different conditions: 20°C, 50% relative humidity (RH); 20°C, 80% RH; 30°C, 50% RH; and 30°C, 80% RH. Samples were collected at N0 , N5 , and A15 , then subjected to survival analysis and comparative transcriptomic analysis in order to help elucidate the underlying mechanisms of airborne survival. Survival analysis shows that a higher humidity and lower temperature were favorable for the airborne survival of K. pneumoniae, and the effect of RH was more remarkable at 20°C than that at 30°C. The RNA-seq results show that during the nebulization phase (N0 vs. N5 ), a total number of 201 differentially expressed genes (DEGs) were identified (103 downregulated and 98 upregulated). Comparison between nebulization and aerosolization phases (N5 vs. A15 ) indicates up to 132 DEGs, with 46 downregulated and 86 upregulated. The most notable groups of genes are those involved in cellular remodeling, metabolism and energy processes. Alarmingly, the mbl gene, which encodes antibiotic resistance in K. pneumoniae, was upregulated during the suspension phase under all the tested conditions. This study provides insights into the control of airborne transmitted diseases.
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Affiliation(s)
- Natasha Maria Barnes
- Department of Biology, Hong Kong Special Administrative Region, Hong Kong Baptist University, Hong Kong, China
- Biological Oceanography Division, CSIR-National Institute of Oceanography, Dona Paula, India
| | - Haoxiang Wu
- Department of Biology, Hong Kong Special Administrative Region, Hong Kong Baptist University, Hong Kong, China
- Institute of Bioresource and Agriculture, Hong Kong Special Administrative Region, Hong Kong Baptist University, Hong Kong, China
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5
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Singh M, Becker M, Godwin AR, Baldock C. Structural studies of elastic fibre and microfibrillar proteins. Matrix Biol Plus 2021; 12:100078. [PMID: 34355160 PMCID: PMC8322146 DOI: 10.1016/j.mbplus.2021.100078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/26/2021] [Accepted: 06/28/2021] [Indexed: 11/27/2022] Open
Abstract
Elastic tissues owe their functional properties to the composition of their extracellular matrices, particularly the range of extracellular, multidomain extensible elastic fibre and microfibrillar proteins. These proteins include elastin, fibrillin, latent TGFβ binding proteins (LTBPs) and collagens, where their biophysical and biochemical properties not only give the matrix structural integrity, but also play a vital role in the mechanisms that underlie tissue homeostasis. Thus far structural information regarding the structure and hierarchical assembly of these molecules has been challenging and the resolution has been limited due to post-translational modification and their multidomain nature leading to flexibility, which together result in conformational and structural heterogeneity. In this review, we describe some of the matrix proteins found in elastic fibres and the new emerging techniques that can shed light on their structure and dynamic properties.
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Affiliation(s)
- Mukti Singh
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
| | - Mark Becker
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
| | - Alan R.F. Godwin
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
| | - Clair Baldock
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
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6
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Beyens A, Pottie L, Sips P, Callewaert B. Clinical and Molecular Delineation of Cutis Laxa Syndromes: Paradigms for Homeostasis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1348:273-309. [PMID: 34807425 DOI: 10.1007/978-3-030-80614-9_13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Cutis laxa (CL) syndromes are a large and heterogeneous group of rare connective tissue disorders that share loose redundant skin as a hallmark clinical feature, which reflects dermal elastic fiber fragmentation. Both acquired and congenital-Mendelian- forms exist. Acquired forms are progressive and often preceded by inflammatory triggers in the skin, but may show systemic elastolysis. Mendelian forms are often pleiotropic in nature and classified upon systemic manifestations and mode of inheritance. Though impaired elastogenesis is a common denominator in all Mendelian forms of CL, the underlying gene defects are diverse and affect structural components of the elastic fiber or impair metabolic pathways interfering with cellular trafficking, proline synthesis, or mitochondrial functioning. In this chapter we provide a detailed overview of the clinical and molecular characteristics of the different cutis laxa types and review the latest insights on elastic fiber assembly and homeostasis from both human and animal studies.
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Affiliation(s)
- Aude Beyens
- Center for Medical Genetics Ghent, Department of Dermatology, Department of Biomolecular Medicine, Ghent University Hospital, Ghent University, Ghent, Belgium
| | - Lore Pottie
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium.,Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Patrick Sips
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium.,Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Bert Callewaert
- Center for Medical Genetics Ghent, Department of Biomolecular Medicine, Ghent University Hospital, Ghent University, Ghent, Belgium.
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7
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Su CT, Jao TM, Urban Z, Huang YJ, See DHW, Tsai YC, Lin WC, Huang JW. LTBP4 affects renal fibrosis by influencing angiogenesis and altering mitochondrial structure. Cell Death Dis 2021; 12:943. [PMID: 34645813 PMCID: PMC8514500 DOI: 10.1038/s41419-021-04214-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 08/25/2021] [Accepted: 09/16/2021] [Indexed: 12/14/2022]
Abstract
Transforming growth factor beta (TGFβ) signalling regulates extracellular matrix accumulation known to be essential for the pathogenesis of renal fibrosis; latent transforming growth factor beta binding protein 4 (LTBP4) is an important regulator of TGFβ activity. To date, the regulation of LTBP4 in renal fibrosis remains unknown. Herein, we report that LTBP4 is upregulated in patients with chronic kidney disease and fibrotic mice kidneys created by unilateral ureteral obstruction (UUO). Mice lacking the short LTBP4 isoform (Ltbp4S-/-) exhibited aggravated tubular interstitial fibrosis (TIF) after UUO, indicating that LTBP4 potentially protects against TIF. Transcriptomic analysis of human proximal tubule cells overexpressing LTBP4 revealed that LTBP4 influences angiogenic pathways; moreover, these cells preserved better mitochondrial respiratory functions and expressed higher vascular endothelial growth factor A (VEGFA) compared to wild-type cells under hypoxia. Results of the tube formation assay revealed that additional LTBP4 in human umbilical vein endothelial cell supernatant stimulates angiogenesis with upregulated vascular endothelial growth factor receptors (VEGFRs). In vivo, aberrant angiogenesis, abnormal mitochondrial morphology and enhanced oxidative stress were observed in Ltbp4S-/- mice after UUO. These results reveal novel molecular functions of LTBP4 stimulating angiogenesis and potentially impacting mitochondrial structure and function. Collectively, our findings indicate that LTBP4 protects against disease progression and may be of therapeutic use in renal fibrosis.
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Affiliation(s)
- Chi-Ting Su
- Renal Division, Department of Internal medicine, National Taiwan University Hospital Yunlin Branch, Douliu, Taiwan
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Medicine, National Taiwan University Cancer Centre Hospital, Taipei, Taiwan
| | - Tzu-Ming Jao
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung City, Taiwan
- Institute of Precision Medicine, National Sun Yat-sen University, Kaohsiung City, Taiwan
| | - Zsolt Urban
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - Yue-Jhu Huang
- Renal Division, Department of Internal medicine, National Taiwan University Hospital Yunlin Branch, Douliu, Taiwan
| | - Daniel H W See
- Renal Division, Department of Internal medicine, National Taiwan University Hospital Yunlin Branch, Douliu, Taiwan
| | - Yao-Chou Tsai
- Renal Division, Department of Internal medicine, National Taiwan University Hospital Yunlin Branch, Douliu, Taiwan
| | - Wei-Chou Lin
- Department of Pathology, National Taiwan University Hospital, Taipei, Taiwan
| | - Jenq-Wen Huang
- Renal Division, Department of Internal medicine, National Taiwan University Hospital Yunlin Branch, Douliu, Taiwan.
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8
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Alanazi YF, Lockhart-Cairns MP, Cain SA, Jowitt TA, Weiss AS, Baldock C. Autosomal Recessive Cutis Laxa 1C Mutations Disrupt the Structure and Interactions of Latent TGFβ Binding Protein-4. Front Genet 2021; 12:706662. [PMID: 34539739 PMCID: PMC8446450 DOI: 10.3389/fgene.2021.706662] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 07/23/2021] [Indexed: 11/29/2022] Open
Abstract
Latent TGFβ binding protein-4 (LTBP4) is a multi-domain glycoprotein, essential for regulating the extracellular bioavailability of TGFβ and assembly of elastic fibre proteins, fibrillin-1 and tropoelastin. LTBP4 mutations are linked to autosomal recessive cutis laxa type 1C (ARCL1C), a rare congenital disease characterised by high mortality and severely disrupted connective tissues. Despite the importance of LTBP4, the structure and molecular consequences of disease mutations are unknown. Therefore, we analysed the structural and functional consequences of three ARCL1C causing point mutations which effect highly conserved cysteine residues. Our structural and biophysical data show that the LTBP4 N- and C-terminal regions are monomeric in solution and adopt extended conformations with the mutations resulting in subtle changes to their conformation. Similar to LTBP1, the N-terminal region is relatively inflexible, whereas the C-terminal region is flexible. Interaction studies show that one C-terminal mutation slightly decreases binding to fibrillin-1. We also found that the LTBP4 C-terminal region directly interacts with tropoelastin which is perturbed by both C-terminal ARCL1C mutations, whereas an N-terminal mutation increased binding to fibulin-4 but did not affect the interaction with heparan sulphate. Our results suggest that LTBP4 mutations contribute to ARCL1C by disrupting the structure and interactions of LTBP4 which are essential for elastogenesis in a range of mammalian connective tissues.
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Affiliation(s)
- Yasmene F Alanazi
- Wellcome Trust Centre for Cell Matrix Research, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Science, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
| | - Michael P Lockhart-Cairns
- Wellcome Trust Centre for Cell Matrix Research, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Science, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
| | - Stuart A Cain
- Wellcome Trust Centre for Cell Matrix Research, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Science, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
| | - Thomas A Jowitt
- Wellcome Trust Centre for Cell Matrix Research, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Science, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
| | - Anthony S Weiss
- Charles Perkins Centre, University of Sydney, Darlington, NSW, Australia.,School of Life and Environmental Sciences, Darlington, NSW, Australia.,Sydney Nano Institute, The University of Sydney, Darlington, NSW, Australia
| | - Clair Baldock
- Wellcome Trust Centre for Cell Matrix Research, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Science, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
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9
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Pottie L, Adamo CS, Beyens A, Lütke S, Tapaneeyaphan P, De Clercq A, Salmon PL, De Rycke R, Gezdirici A, Gulec EY, Khan N, Urquhart JE, Newman WG, Metcalfe K, Efthymiou S, Maroofian R, Anwar N, Maqbool S, Rahman F, Altweijri I, Alsaleh M, Abdullah SM, Al-Owain M, Hashem M, Houlden H, Alkuraya FS, Sips P, Sengle G, Callewaert B. Bi-allelic premature truncating variants in LTBP1 cause cutis laxa syndrome. Am J Hum Genet 2021; 108:1095-1114. [PMID: 33991472 PMCID: PMC8206382 DOI: 10.1016/j.ajhg.2021.04.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Accepted: 04/22/2021] [Indexed: 02/02/2023] Open
Abstract
Latent transforming growth factor β (TGFβ)-binding proteins (LTBPs) are microfibril-associated proteins essential for anchoring TGFβ in the extracellular matrix (ECM) as well as for correct assembly of ECM components. Variants in LTBP2, LTBP3, and LTBP4 have been identified in several autosomal recessive Mendelian disorders with skeletal abnormalities with or without impaired development of elastin-rich tissues. Thus far, the human phenotype associated with LTBP1 deficiency has remained enigmatic. In this study, we report homozygous premature truncating LTBP1 variants in eight affected individuals from four unrelated consanguineous families. Affected individuals present with connective tissue features (cutis laxa and inguinal hernia), craniofacial dysmorphology, variable heart defects, and prominent skeletal features (craniosynostosis, short stature, brachydactyly, and syndactyly). In vitro studies on proband-derived dermal fibroblasts indicate distinct molecular mechanisms depending on the position of the variant in LTBP1. C-terminal variants lead to an altered LTBP1 loosely anchored in the microfibrillar network and cause increased ECM deposition in cultured fibroblasts associated with excessive TGFβ growth factor activation and signaling. In contrast, N-terminal truncation results in a loss of LTBP1 that does not alter TGFβ levels or ECM assembly. In vivo validation with two independent zebrafish lines carrying mutations in ltbp1 induce abnormal collagen fibrillogenesis in skin and intervertebral ligaments and ectopic bone formation on the vertebrae. In addition, one of the mutant zebrafish lines shows voluminous and hypo-mineralized vertebrae. Overall, our findings in humans and zebrafish show that LTBP1 function is crucial for skin and bone ECM assembly and homeostasis.
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Affiliation(s)
- Lore Pottie
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent 9000, Belgium; Department of Biomolecular Medicine, Ghent University, Ghent 9000, Belgium
| | - Christin S Adamo
- Center for Biochemistry, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne 50931, Germany; Department of Pediatrics and Adolescent Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne 50931, Germany
| | - Aude Beyens
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent 9000, Belgium; Department of Biomolecular Medicine, Ghent University, Ghent 9000, Belgium; Department of Dermatology, Ghent University Hospital, Ghent 9000, Belgium
| | - Steffen Lütke
- Center for Biochemistry, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne 50931, Germany; Department of Pediatrics and Adolescent Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne 50931, Germany
| | - Piyanoot Tapaneeyaphan
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent 9000, Belgium; Department of Biomolecular Medicine, Ghent University, Ghent 9000, Belgium
| | - Adelbert De Clercq
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent 9000, Belgium; Department of Biomolecular Medicine, Ghent University, Ghent 9000, Belgium
| | | | - Riet De Rycke
- Department of Biomedical Molecular Biology, Ghent University, Ghent 9052, Belgium; VIB Center for Inflammation Research, Ghent 9052, Belgium; Ghent University Expertise Centre for Transmission Electron Microscopy and VIB Bioimaging Core, Ghent 9052, Belgium
| | - Alper Gezdirici
- Department of Medical Genetics, Basaksehir Cam and Sakura City Hospital, Istanbul 34480, Turkey
| | - Elif Yilmaz Gulec
- Department of Medical Genetics, Kanuni Sultan Suleyman Training and Research Hospital, Health Sciences University, Istanbul 34303, Turkey
| | - Naz Khan
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9WL, UK; Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Manchester M13 9WL, UK
| | - Jill E Urquhart
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9WL, UK; Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Manchester M13 9WL, UK
| | - William G Newman
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9WL, UK; Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Manchester M13 9WL, UK
| | - Kay Metcalfe
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Manchester M13 9WL, UK
| | - Stephanie Efthymiou
- Department of Neuromuscular Disorders, UCL Institute of Neurology, London WC1N 3BG, UK
| | - Reza Maroofian
- Department of Neuromuscular Disorders, UCL Institute of Neurology, London WC1N 3BG, UK
| | - Najwa Anwar
- Development and Behavioral Pediatrics Department, Institute of Child Health and The Children Hospital, Lahore 54000, Pakistan
| | - Shazia Maqbool
- Development and Behavioral Pediatrics Department, Institute of Child Health and The Children Hospital, Lahore 54000, Pakistan
| | - Fatima Rahman
- Development and Behavioral Pediatrics Department, Institute of Child Health and The Children Hospital, Lahore 54000, Pakistan
| | - Ikhlass Altweijri
- Department of Neurosurgery, King Khalid University Hospital, Riyadh 11211, Saudi Arabia
| | - Monerah Alsaleh
- Heart Centre, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia
| | - Sawsan Mohamed Abdullah
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia
| | - Mohammad Al-Owain
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia; Department of Anatomy and Cell Biology, College of Medicine, Alfaisal University, Riyadh 11211, Saudi Arabia
| | - Mais Hashem
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia
| | - Henry Houlden
- Department of Neuromuscular Disorders, UCL Institute of Neurology, London WC1N 3BG, UK
| | - Fowzan S Alkuraya
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia; Department of Anatomy and Cell Biology, College of Medicine, Alfaisal University, Riyadh 11211, Saudi Arabia
| | - Patrick Sips
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent 9000, Belgium; Department of Biomolecular Medicine, Ghent University, Ghent 9000, Belgium
| | - Gerhard Sengle
- Center for Biochemistry, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne 50931, Germany; Department of Pediatrics and Adolescent Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne 50931, Germany; Center for Molecular Medicine Cologne, University of Cologne, Robert-Koch-Street 21, Cologne 50931, Germany; Cologne Center for Musculoskeletal Biomechanics, Cologne 50931, Germany
| | - Bert Callewaert
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent 9000, Belgium; Department of Biomolecular Medicine, Ghent University, Ghent 9000, Belgium.
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10
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Su CT, Urban Z. LTBP4 in Health and Disease. Genes (Basel) 2021; 12:genes12060795. [PMID: 34071145 PMCID: PMC8224675 DOI: 10.3390/genes12060795] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/14/2021] [Accepted: 05/21/2021] [Indexed: 12/20/2022] Open
Abstract
Latent transforming growth factor β (TGFβ)-binding protein (LTBP) 4, a member of the LTBP family, shows structural homology with fibrillins. Both these protein types are characterized by calcium-binding epidermal growth factor-like repeats interspersed with 8-cysteine domains. Based on its domain composition and distribution, LTBP4 is thought to adopt an extended structure, facilitating the linear deposition of tropoelastin onto microfibrils. In humans, mutations in LTBP4 result in autosomal recessive cutis laxa type 1C, characterized by redundant skin, pulmonary emphysema, and valvular heart disease. LTBP4 is an essential regulator of TGFβ signaling and is related to development, immunity, injury repair, and diseases, playing a central role in regulating inflammation, fibrosis, and cancer progression. In this review, we focus on medical disorders or diseases that may be manipulated by LTBP4 in order to enhance the understanding of this protein.
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Affiliation(s)
- Chi-Ting Su
- Department of Internal Medicine, Renal Division, National Taiwan University Hospital Yunlin Branch, Douliu 640, Taiwan;
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA
- Department of Medicine, National Taiwan University Cancer Center Hospital, Taipei 106, Taiwan
| | - Zsolt Urban
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA
- Correspondence: ; Tel.: +1-412-648-8269
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11
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Schmelzer CEH, Duca L. Elastic fibers: formation, function, and fate during aging and disease. FEBS J 2021; 289:3704-3730. [PMID: 33896108 DOI: 10.1111/febs.15899] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 03/16/2021] [Accepted: 03/22/2021] [Indexed: 01/09/2023]
Abstract
Elastic fibers are extracellular components of higher vertebrates and confer elasticity and resilience to numerous tissues and organs such as large blood vessels, lungs, and skin. Their formation and maturation take place in a complex multistage process called elastogenesis. It requires interactions between very different proteins but also other molecules and leads to the deposition and crosslinking of elastin's precursor on a scaffold of fibrillin-rich microfibrils. Mature fibers are exceptionally resistant to most influences and, under healthy conditions, retain their biomechanical function over the life of the organism. However, due to their longevity, they accumulate damages during aging. These are caused by proteolytic degradation, formation of advanced glycation end products, calcification, oxidative damage, aspartic acid racemization, lipid accumulation, carbamylation, and mechanical fatigue. The resulting changes can lead to diminution or complete loss of elastic fiber function and ultimately affect morbidity and mortality. Particularly, the production of elastokines has been clearly shown to influence several life-threatening diseases. Moreover, the structure, distribution, and abundance of elastic fibers are directly or indirectly influenced by a variety of inherited pathological conditions, which mainly affect organs and tissues such as skin, lungs, or the cardiovascular system. A distinction can be made between microfibril-related inherited diseases that are the result of mutations in diverse microfibril genes and indirectly affect elastogenesis, and elastinopathies that are linked to changes in the elastin gene. This review gives an overview on the formation, structure, and function of elastic fibers and their fate over the human lifespan in health and disease.
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Affiliation(s)
- Christian E H Schmelzer
- Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle (Saale), Germany.,Institute of Pharmacy, Faculty of Natural Sciences I, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Laurent Duca
- UMR CNRS 7369 MEDyC, SFR CAP-Sante, Université de Reims Champagne-Ardenne, France
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12
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Heinz A. Elastic fibers during aging and disease. Ageing Res Rev 2021; 66:101255. [PMID: 33434682 DOI: 10.1016/j.arr.2021.101255] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/29/2020] [Accepted: 12/30/2020] [Indexed: 02/08/2023]
Abstract
Elastic fibers are essential constituents of the extracellular matrix of higher vertebrates and endow several tissues and organs including lungs, skin and blood vessels with elasticity and resilience. During the human lifespan, elastic fibers are exposed to a variety of enzymatic, chemical and biophysical influences, and accumulate damage due to their low turnover. Aging of elastin and elastic fibers involves enzymatic degradation, oxidative damage, glycation, calcification, aspartic acid racemization, binding of lipids and lipid peroxidation products, carbamylation and mechanical fatigue. These processes can trigger an impairment or loss of elastic fiber function and are associated with severe pathologies. There are different inherited or acquired pathological conditions, which influence the structure and function of elastic fibers and microfibrils predominantly in the cardiorespiratory system and skin. Inherited elastic-fiber pathologies have a direct or indirect impact on elastic-fiber formation due to mutations in the fibrillin genes (fibrillinopathies), in the elastin gene (elastinopathies) or in genes encoding proteins that are associated with microfibrils or elastic fibers. Acquired elastic-fiber pathologies appear age-related or as a result of multiple factors impairing tissue homeostasis. This review gives an overview on the fate of elastic fibers over the human lifespan in health and disease.
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13
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Adamo CS, Zuk AV, Sengle G. The fibrillin microfibril/elastic fibre network: A critical extracellular supramolecular scaffold to balance skin homoeostasis. Exp Dermatol 2020; 30:25-37. [PMID: 32920888 DOI: 10.1111/exd.14191] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 09/01/2020] [Accepted: 09/03/2020] [Indexed: 01/08/2023]
Abstract
Supramolecular networks composed of fibrillins (fibrillin-1 and fibrillin-2) and associated ligands form intricate cellular microenvironments which balance skin homoeostasis and direct remodelling. Fibrillins assemble into microfibrils which are not only indispensable for conferring elasticity to the skin, but also control the bioavailability of growth factors targeted to the extracellular matrix architecture. Fibrillin microfibrils (FMF) represent the core scaffolds for elastic fibre formation, and they also decorate the surface of elastic fibres and form independent networks. In normal dermis, elastic fibres are suspended in a three-dimensional basket-like lattice of FMF intersecting basement membranes at the dermal-epidermal junction and thus conferring pliability to the skin. The importance of FMF for skin homoeostasis is illustrated by the clinical features caused by mutations in the human fibrillin genes (FBN1, FBN2), summarized as "fibrillinopathies." In skin, fibrillin mutations result in phenotypes ranging from thick, stiff and fibrotic skin to thin, lax and hyperextensible skin. The most plausible explanation for this spectrum of phenotypic outcomes is that FMF regulate growth factor signalling essential for proper growth and homoeostasis of the skin. Here, we will give an overview about the current understanding of the underlying pathomechanisms leading to fibrillin-dependent fibrosis as well as forms of cutis laxa caused by mutational inactivation of FMF-associated ligands.
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Affiliation(s)
- Christin S Adamo
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany.,Department of Pediatrics and Adolescent Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Alexandra V Zuk
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany
| | - Gerhard Sengle
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany.,Department of Pediatrics and Adolescent Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.,Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.,Cologne Center for Musculoskeletal Biomechanics (CCMB), Cologne, Germany
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14
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Gupta N, Langeh N, Sridharan A, Kabra M. Identification of a Novel 19-bp Deletion Mutation in LTBP4 Using Exome Sequencing in Two Siblings with Autosomal Recessive Cutis Laxa Type 1C. J Pediatr Genet 2020; 9:125-131. [PMID: 32341818 DOI: 10.1055/s-0039-1698806] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 09/08/2019] [Indexed: 10/25/2022]
Abstract
Autosomal recessive type I cutis laxa is genetically heterogeneous. Biallelic mutations in latent transforming growth factor β-binding protein 4 (LTBP4; MIM*604710) lead to type 1C cutis laxa due to nonsense, frameshift, single base pair indels, or duplication mutations. In this report, we describe the first Indian family with cutis laxa as a result of a novel 19 base pair homozygous deletion leading to premature termination of short isoform LTBP-4S.
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Affiliation(s)
- Neerja Gupta
- Division of Genetics, Department of Pediatrics, All India Institute of Medical Sciences (AIIMS), New Delhi, India
| | - Nitika Langeh
- Division of Genetics, Department of Pediatrics, All India Institute of Medical Sciences (AIIMS), New Delhi, India
| | | | - Madhulika Kabra
- Division of Genetics, Department of Pediatrics, All India Institute of Medical Sciences (AIIMS), New Delhi, India
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15
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Schmelzer CEH, Hedtke T, Heinz A. Unique molecular networks: Formation and role of elastin cross-links. IUBMB Life 2019; 72:842-854. [PMID: 31834666 DOI: 10.1002/iub.2213] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 11/30/2019] [Indexed: 01/11/2023]
Abstract
Elastic fibers are essential assemblies of vertebrates and confer elasticity and resilience to various organs including blood vessels, lungs, skin, and ligaments. Mature fibers, which comprise a dense and insoluble elastin core and a microfibrillar mantle, are extremely resistant toward intrinsic and extrinsic influences and maintain elastic function over the human lifespan in healthy conditions. The oxidative deamination of peptidyl lysine to peptidyl allysine in elastin's precursor tropoelastin is a crucial posttranslational step in their formation. The modification is catalyzed by members of the family of lysyl oxidases and the starting point for subsequent manifold condensation reactions that eventually lead to the highly cross-linked elastomer. This review summarizes the current understanding of the formation of cross-links within and between the monomer molecules, the molecular sites, and cross-link types involved and the pathological consequences of abnormalities in the cross-linking process.
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Affiliation(s)
- Christian E H Schmelzer
- Department of Biological and Macromolecular Materials, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle (Saale), Germany.,Institute of Pharmacy, Faculty of Natural Sciences I, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Tobias Hedtke
- Department of Biological and Macromolecular Materials, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle (Saale), Germany.,Institute of Pharmacy, Faculty of Natural Sciences I, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Andrea Heinz
- Department of Pharmacy, LEO Foundation Center for Cutaneous Drug Delivery, University of Copenhagen, Copenhagen, Denmark
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16
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Fibulin-4 exerts a dual role in LTBP-4L-mediated matrix assembly and function. Proc Natl Acad Sci U S A 2019; 116:20428-20437. [PMID: 31548410 DOI: 10.1073/pnas.1901048116] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Elastogenesis is a hierarchical process by which cells form functional elastic fibers, providing elasticity and the ability to regulate growth factor bioavailability in tissues, including blood vessels, lung, and skin. This process requires accessory proteins, including fibulin-4 and -5, and latent TGF binding protein (LTBP)-4. Our data demonstrate mechanisms in elastogenesis, focusing on the interaction and functional interdependence between fibulin-4 and LTBP-4L and its impact on matrix deposition and function. We show that LTBP-4L is not secreted in the expected extended structure based on its domain composition, but instead adopts a compact conformation. Interaction with fibulin-4 surprisingly induced a conformational switch from the compact to an elongated LTBP-4L structure. This conversion was only induced by fibulin-4 multimers associated with increased avidity for LTBP-4L; fibulin-4 monomers were inactive. The fibulin-4-induced conformational change caused functional consequences in LTBP-4L in terms of binding to other elastogenic proteins, including fibronectin and fibrillin-1, and of LTBP-4L assembly. A transient exposure of LTBP-4L with fibulin-4 was sufficient to stably induce conformational and functional changes; a stable complex was not required. These data define fibulin-4 as a molecular extracellular chaperone for LTBP-4L. The altered LTBP-4L conformation also promoted elastogenesis, but only in the presence of fibulin-4, which is required to escort tropoelastin onto the extended LTBP-4L molecule. Altogether, this study provides a dual mechanism for fibulin-4 in 1) inducing a stable conformational and functional change in LTBP-4L, and 2) promoting deposition of tropoelastin onto the elongated LTBP-4L.
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17
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Recent updates on the molecular network of elastic fiber formation. Essays Biochem 2019; 63:365-376. [PMID: 31395654 DOI: 10.1042/ebc20180052] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 07/12/2019] [Accepted: 07/26/2019] [Indexed: 12/20/2022]
Abstract
Elastic fibers confer elasticity and recoiling to tissues and organs and play an essential role in induction of biochemical responses in a cell against mechanical forces derived from the microenvironment. The core component of elastic fibers is elastin (ELN), which is secreted as the monomer tropoelastin from elastogenic cells, and undergoes self-aggregation, cross-linking and deposition on to microfibrils, and assemble into insoluble ELN polymers. For elastic fibers to form, a microfibril scaffold (primarily formed by fibrillin-1 (FBN1)) is required. Numerous elastic fiber-associated proteins are involved in each step of elastogenesis and they instruct and/or facilitate the elastogenesis processes. In this review, we designated five proteins as key molecules in elastic fiber formation, including ELN, FBN1, fibulin-4 (FBLN4), fibulin-5 (FBLN5), and latent TGFβ-binding protein-4 (LTBP4). ELN and FBN1 serve as building blocks for elastic fibers. FBLN5, FBLN4 and LTBP4 have been demonstrated to play crucial roles in elastogenesis through knockout studies in mice. Using these molecules as a platform and expanding the elastic fiber network through the generation of an interactome map, we provide a concise review of elastogenesis with a recent update as well as discuss various biological functions of elastic fiber-associated proteins beyond elastogenesis in vivo.
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18
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Ramaswamy AK, Sides RE, Cunnane EM, Lorentz KL, Reines LM, Vorp DA, Weinbaum JS. Adipose-derived stromal cell secreted factors induce the elastogenesis cascade within 3D aortic smooth muscle cell constructs. Matrix Biol Plus 2019; 4:100014. [PMID: 33543011 PMCID: PMC7852215 DOI: 10.1016/j.mbplus.2019.100014] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 08/19/2019] [Accepted: 08/28/2019] [Indexed: 02/07/2023] Open
Abstract
Objective Elastogenesis within the medial layer of the aortic wall involves a cascade of events orchestrated primarily by smooth muscle cells, including transcription of elastin and a cadre of elastin chaperone matricellular proteins, deposition and cross-linking of tropoelastin coacervates, and maturation of extracellular matrix fiber structures to form mechanically competent vascular tissue. Elastic fiber disruption is associated with aortic aneurysm; in aneurysmal disease a thin and weakened wall leads to a high risk of rupture if left untreated, and non-surgical treatments for small aortic aneurysms are currently limited. This study analyzed the effect of adipose-derived stromal cell secreted factors on each step of the smooth muscle cell elastogenesis cascade within a three-dimensional fibrin gel culture platform. Approach and results We demonstrate that adipose-derived stromal cell secreted factors induce an increase in smooth muscle cell transcription of tropoelastin, fibrillin-1, and chaperone proteins fibulin-5, lysyl oxidase, and lysyl oxidase-like 1, formation of extracellular elastic fibers, insoluble elastin and collagen protein fractions in dynamically-active 30-day constructs, and a mechanically competent matrix after 30 days in culture. Conclusion Our results reveal a potential avenue for an elastin-targeted small aortic aneurysm therapeutic, acting as a supplement to the currently employed passive monitoring strategy. Additionally, the elastogenesis analysis workflow explored here could guide future mechanistic studies of elastin formation, which in turn could lead to new non-surgical treatment strategies. Stromal cells stimulate smooth muscle cells (SMC) using paracrine signals. Stimulated SMC make RNA for both elastin and associated proteins. After protein synthesis, new elastic fibers form that contain insoluble elastin. Stromal cell products could promote elastin production in vivo.
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Key Words
- AA, aortic aneurysm
- ACA, epsilon-amino caproic acid
- ASC, adipose-derived stromal cell
- ASC-SF, ASC secreted factors
- Aneurysm
- Aorta
- ECM, extracellular matrix
- Elastin
- Extracellular matrix
- FBS, fetal bovine serum
- LOX, lysyl oxidase
- LOXL-1, LOX-like 1
- LTBP, latent TGF-β binding protein
- NCM, non-conditioned media
- NT, no treatment
- PBS, phosphate buffered saline
- RT, reverse transcriptase
- SMC, smooth muscle cell
- TGF-β, transforming growth factor-β
- Vascular regeneration
- qPCR, quantitative polymerase chain reaction
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Affiliation(s)
- Aneesh K. Ramaswamy
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Rachel E. Sides
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Eoghan M. Cunnane
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- Tissue Engineering Research Group, Department of Anatomy, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Katherine L. Lorentz
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Leila M. Reines
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - David A. Vorp
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States of America
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, United States of America
- Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Justin S. Weinbaum
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA, United States of America
- Corresponding author at: Department of Bioengineering, University of Pittsburgh, Center for Bioengineering, Suite 300, 300 Technology Drive, Pittsburgh, PA 15261, United States of America.
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19
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Godwin ARF, Singh M, Lockhart-Cairns MP, Alanazi YF, Cain SA, Baldock C. The role of fibrillin and microfibril binding proteins in elastin and elastic fibre assembly. Matrix Biol 2019; 84:17-30. [PMID: 31226403 PMCID: PMC6943813 DOI: 10.1016/j.matbio.2019.06.006] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 06/16/2019] [Accepted: 06/17/2019] [Indexed: 12/17/2022]
Abstract
Fibrillin is a large evolutionarily ancient extracellular glycoprotein that assembles to form beaded microfibrils which are essential components of most extracellular matrices. Fibrillin microfibrils have specific biomechanical properties to endow animal tissues with limited elasticity, a fundamental feature of the durable function of large blood vessels, skin and lungs. They also form a template for elastin deposition and provide a platform for microfibril-elastin binding proteins to interact in elastic fibre assembly. In addition to their structural role, fibrillin microfibrils mediate cell signalling via integrin and syndecan receptors, and microfibrils sequester transforming growth factor (TGF)β family growth factors within the matrix to provide a tissue store which is critical for homeostasis and remodelling.
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Affiliation(s)
- Alan R F Godwin
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
| | - Mukti Singh
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
| | - Michael P Lockhart-Cairns
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
| | - Yasmene F Alanazi
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
| | - Stuart A Cain
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK.
| | - Clair Baldock
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK.
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20
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Chen X, Yang Y, Chang T, Xu B, Wei H. Comparative Transcriptome Analysis of Unusual Localized Skin Laxity in Sika Deer ( Cervus nippon). DNA Cell Biol 2019; 38:670-677. [PMID: 31188027 DOI: 10.1089/dna.2019.4730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Cutis laxa represents a heterogeneous group of rare, inherited, or acquired connective tissue disorders with the common feature of loose and redundant skin with decreased elasticity. The skin of affected deer showed abnormal collagen fiber morphology. To identify the differentially expressed genes of the unusual localized skin laxity in sika deer, we performed transcriptome analysis in the affected and control sika deer. The transcriptome analysis showed 700 genes with significant differential expression in the affected skin as compared with normal skin. Pathway analysis revealed an enrichment of genes involved in tumor necrosis factor signaling, the extracellular matrix-receptor interaction, platelet activation, and Huntington's disease. A gene network was constructed, and the hub nodes such as PTGS2, THBS1, COL1A1, FOS, and NOS3 were found through PPI network analysis, which may contributed to the unusual localized skin laxity in sika deer. Abnormal expression patterns of genes during the development of the affected sika deer were successfully uncovered in the present study, which provides a reference for revealing the related mechanism underlying cutis laxa in sika deer and human beings.
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Affiliation(s)
- Xiumin Chen
- 1 Institute of Special Animals and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Yifeng Yang
- 1 Institute of Special Animals and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, China.,2 Key Laboratory of Molecular Biology in Special Economic Animals, Changchun, China
| | - Tong Chang
- 1 Institute of Special Animals and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Baozeng Xu
- 1 Institute of Special Animals and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, China.,2 Key Laboratory of Molecular Biology in Special Economic Animals, Changchun, China
| | - Haijun Wei
- 1 Institute of Special Animals and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, China.,2 Key Laboratory of Molecular Biology in Special Economic Animals, Changchun, China
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21
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Zigrino P, Sengle G. Fibrillin microfibrils and proteases, key integrators of fibrotic pathways. Adv Drug Deliv Rev 2019; 146:3-16. [PMID: 29709492 DOI: 10.1016/j.addr.2018.04.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 04/12/2018] [Accepted: 04/25/2018] [Indexed: 02/06/2023]
Abstract
Supramolecular networks composed of multi-domain ECM proteins represent intricate cellular microenvironments which are required to balance tissue homeostasis and direct remodeling. Structural deficiency in ECM proteins results in imbalances in ECM-cell communication resulting often times in fibrotic reactions. To understand how individual components of the ECM integrate communication with the cell surface by presenting growth factors or providing fine-tuned biomechanical properties is mandatory for gaining a better understanding of disease mechanisms in the quest for new therapeutic approaches. Here we provide an overview about what we can learn from inherited connective tissue disorders caused primarily by mutations in fibrillin-1 and binding partners as well as by altered ECM processing leading to defined structural changes and similar functional knock-in mouse models. We will utilize this knowledge to propose new molecular hypotheses which should be tested in future studies.
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22
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Burger J, van Vliet N, van Heijningen P, Kumra H, Kremers GJ, Alves M, van Cappellen G, Yanagisawa H, Reinhardt DP, Kanaar R, van der Pluijm I, Essers J. Fibulin-4 deficiency differentially affects cytoskeleton structure and dynamics as well as TGFβ signaling. Cell Signal 2019; 58:65-78. [DOI: 10.1016/j.cellsig.2019.02.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 02/28/2019] [Accepted: 02/28/2019] [Indexed: 12/27/2022]
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23
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Elastic fibers and biomechanics of the aorta: Insights from mouse studies. Matrix Biol 2019; 85-86:160-172. [PMID: 30880160 DOI: 10.1016/j.matbio.2019.03.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 02/28/2019] [Accepted: 03/04/2019] [Indexed: 12/14/2022]
Abstract
Elastic fibers are major components of the extracellular matrix (ECM) in the aorta and support a life-long cycling of stretch and recoil. Elastic fibers are formed from mid-gestation throughout early postnatal development and the synthesis is regulated at multiple steps, including coacervation, deposition, cross-linking, and assembly of insoluble elastin onto microfibril scaffolds. To date, more than 30 molecules have been shown to associate with elastic fibers and some of them play a critical role in the formation and maintenance of elastic fibers in vivo. Because the aorta is subjected to high pressure from the left ventricle, elasticity of the aorta provides the Windkessel effect and maintains stable blood flow to distal organs throughout the cardiac cycle. Disruption of elastic fibers due to congenital defects, inflammation, or aging dramatically reduces aortic elasticity and affects overall vessel mechanics. Another important component in the aorta is the vascular smooth muscle cells (SMCs). Elastic fibers and SMCs alternate to create a highly organized medial layer within the aortic wall. The physical connections between elastic fibers and SMCs form the elastin-contractile units and maintain cytoskeletal organization and proper responses of SMCs to mechanical strain. In this review, we revisit the components of elastic fibers and their roles in elastogenesis and how a loss of each component affects biomechanics of the aorta. Finally, we discuss the significance of elastin-contractile units in the maintenance of SMC function based on knowledge obtained from mouse models of human disease.
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24
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Chen X, Yang Y, Xu B, Wei H. Unusual localized skin laxity in three sika deer. Vet Dermatol 2018; 29:542-544. [DOI: 10.1111/vde.12694] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Xiumin Chen
- Institute of Special Animals and Plants Sciences; Chinese Academy of Agricultural Sciences; Changchun 130112 China
| | - Yifeng Yang
- State Key Laboratory for Molecular Biology of Special Economic Animals; Changchun 130112 China
| | - Baozeng Xu
- State Key Laboratory for Molecular Biology of Special Economic Animals; Department of Animal Breeding innovation; Institute of Special Animals and Plants Sciences; Chinese Academy of Agricultural Sciences; Changchun 130112 China
| | - Haijun Wei
- State Key Laboratory for Molecular Biology of Special Economic Animals; Department of Animal Breeding innovation; Institute of Special Animals and Plants Sciences; Chinese Academy of Agricultural Sciences; Changchun 130112 China
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25
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Fibrillin microfibrils and elastic fibre proteins: Functional interactions and extracellular regulation of growth factors. Semin Cell Dev Biol 2018; 89:109-117. [PMID: 30016650 PMCID: PMC6461133 DOI: 10.1016/j.semcdb.2018.07.016] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Revised: 07/04/2018] [Accepted: 07/13/2018] [Indexed: 02/02/2023]
Abstract
Fibrillin microfibrils are extensible polymers that endow connective tissues with long-range elasticity and have widespread distributions in both elastic and non-elastic tissues. They act as a template for elastin deposition during elastic fibre formation and are essential for maintaining the integrity of tissues such as blood vessels, lung, skin and ocular ligaments. A reduction in fibrillin is seen in tissues in vascular ageing, chronic obstructive pulmonary disease, skin ageing and UV induced skin damage, and age-related vision deterioration. Most mutations in fibrillin cause Marfan syndrome, a genetic disease characterised by overgrowth of the long bones and other skeletal abnormalities with cardiovascular and eye defects. However, mutations in fibrillin and fibrillin-binding proteins can also cause short-stature pathologies. All of these diseases have been linked to dysregulated growth factor signalling which forms a major functional role for fibrillin.
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26
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Goumans MJ, Ten Dijke P. TGF-β Signaling in Control of Cardiovascular Function. Cold Spring Harb Perspect Biol 2018; 10:cshperspect.a022210. [PMID: 28348036 DOI: 10.1101/cshperspect.a022210] [Citation(s) in RCA: 192] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Genetic studies in animals and humans indicate that gene mutations that functionally perturb transforming growth factor β (TGF-β) signaling are linked to specific hereditary vascular syndromes, including Osler-Rendu-Weber disease or hereditary hemorrhagic telangiectasia and Marfan syndrome. Disturbed TGF-β signaling can also cause nonhereditary disorders like atherosclerosis and cardiac fibrosis. Accordingly, cell culture studies using endothelial cells or smooth muscle cells (SMCs), cultured alone or together in two- or three-dimensional cell culture assays, on plastic or embedded in matrix, have shown that TGF-β has a pivotal effect on endothelial and SMC proliferation, differentiation, migration, tube formation, and sprouting. Moreover, TGF-β can stimulate endothelial-to-mesenchymal transition, a process shown to be of key importance in heart valve cushion formation and in various pathological vascular processes. Here, we discuss the roles of TGF-β in vasculogenesis, angiogenesis, and lymphangiogenesis and the deregulation of TGF-β signaling in cardiovascular diseases.
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Affiliation(s)
- Marie-José Goumans
- Department of Molecular Cell Biology and Cancer Genomics Centre Netherlands, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
| | - Peter Ten Dijke
- Department of Molecular Cell Biology and Cancer Genomics Centre Netherlands, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
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27
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LTBPs in biology and medicine: LTBP diseases. Matrix Biol 2017; 71-72:90-99. [PMID: 29217273 DOI: 10.1016/j.matbio.2017.11.014] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 11/30/2017] [Accepted: 11/30/2017] [Indexed: 12/21/2022]
Abstract
The latent transforming growth factor (TGF) β binding proteins (LTBP) are crucial mediators of TGFβ function, as they control growth factor secretion, matrix deposition, presentation and activation. Deficiencies in specific LTBP isoforms yield discrete phenotypes representing defects in bone, lung and cardiovascular development mediated by loss of TGFβ signaling. Additional phenotypes represent loss of unique TGFβ-independent features of LTBP effects on elastogenesis and microfibril assembly. Thus, the LTBPs act as sensors for the regulation of both growth factor activity and matrix function.
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28
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Schiavinato A, Keene DR, Imhof T, Doliana R, Sasaki T, Sengle G. Fibulin-4 deposition requires EMILIN-1 in the extracellular matrix of osteoblasts. Sci Rep 2017; 7:5526. [PMID: 28717224 PMCID: PMC5514116 DOI: 10.1038/s41598-017-05835-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 06/05/2017] [Indexed: 11/09/2022] Open
Abstract
Tissue microenvironments formed by extracellular matrix networks play an important role in regulating tissue structure and function. Extracellular microfibrillar networks composed of fibrillins and their associated ligands such as LTBPs, fibulins, and EMILINs are of particular interest in this regard since they provide a specialized cellular microenvironment guiding proper morphology and functional behavior of specialized cell types. To understand how cellular microenvironments composed of intricate microfibrillar networks influence cell fate decisions in a contextual manner, more information about the spatiotemporal localization, deposition, and function of their components is required. By employing confocal immunofluorescence and electron microscopy we investigated the localization and extracellular matrix deposition of EMILIN-1 and -2 in tissues of the skeletal system such as cartilage and bone as well as in in vitro cultures of osteoblasts. We found that upon RNAi mediated depletion of EMILIN-1 in primary calvarial osteoblasts and MC3T3-E1 cells only fibulin-4 matrix deposition was lost while other fibulin family members or LTBPs remained unaffected. Immunoprecipitation and ELISA-style binding assays confirmed a direct interaction between EMILIN-1 and fibulin-4. Our data suggest a new function for EMILIN-1 which implies the guidance of linear fibulin-4 matrix deposition and thereby fibulin-4 fiber formation.
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Affiliation(s)
- Alvise Schiavinato
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany
| | | | - Thomas Imhof
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany.,Institute for Dental Research and Oral Musculoskeletal Biology, Medical Faculty, University of Cologne, 50931, Cologne, Germany
| | - Roberto Doliana
- Experimental Oncology 2, CRO, IRCCS, National Cancer Institute, Aviano, PN, Italy
| | - Takako Sasaki
- Department of Biochemistry II, Faculty of Medicine, Oita University, Oita, 879-5593, Japan
| | - Gerhard Sengle
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany. .,Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.
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29
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Bultmann-Mellin I, Dinger K, Debuschewitz C, Loewe KMA, Melcher Y, Plum MTW, Appel S, Rappl G, Willenborg S, Schauss AC, Jüngst C, Krüger M, Dressler S, Nakamura T, Wempe F, Alejandre Alcázar MA, Sterner-Kock A. Role of LTBP4 in alveolarization, angiogenesis, and fibrosis in lungs. Am J Physiol Lung Cell Mol Physiol 2017; 313:L687-L698. [PMID: 28684544 DOI: 10.1152/ajplung.00031.2017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 06/22/2017] [Accepted: 06/29/2017] [Indexed: 12/31/2022] Open
Abstract
Deficiency of the extracellular matrix protein latent transforming growth factor-β (TGF-β)-binding protein-4 (LTBP4) results in lack of intact elastic fibers, which leads to disturbed pulmonary development and lack of normal alveolarization in humans and mice. Formation of alveoli and alveolar septation in pulmonary development requires the concerted interaction of extracellular matrix proteins, growth factors such as TGF-β, fibroblasts, and myofibroblasts to promote elastogenesis as well as vascular formation in the alveolar septae. To investigate the role of LTBP4 in this context, lungs of LTBP4-deficient (Ltbp4-/-) mice were analyzed in close detail. We elucidate the role of LTBP4 in pulmonary alveolarization and show that three different, interacting mechanisms might contribute to alveolar septation defects in Ltbp4-/- lungs: 1) absence of an intact elastic fiber network, 2) reduced angiogenesis, and 3) upregulation of TGF-β activity resulting in profibrotic processes in the lung.
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Affiliation(s)
- Insa Bultmann-Mellin
- Center for Experimental Medicine, Medical Faculty, University of Cologne, Cologne, Germany
| | - Katharina Dinger
- Center for Experimental Medicine, Medical Faculty, University of Cologne, Cologne, Germany.,Department of Pediatrics and Adolescent Medicine, Medical Faculty, University of Cologne, Cologne, Germany
| | - Carolin Debuschewitz
- Center for Experimental Medicine, Medical Faculty, University of Cologne, Cologne, Germany
| | - Katharina M A Loewe
- Center for Experimental Medicine, Medical Faculty, University of Cologne, Cologne, Germany
| | - Yvonne Melcher
- Center for Experimental Medicine, Medical Faculty, University of Cologne, Cologne, Germany
| | - Miro T W Plum
- Center for Experimental Medicine, Medical Faculty, University of Cologne, Cologne, Germany
| | - Sarah Appel
- Department of Pediatrics and Adolescent Medicine, Medical Faculty, University of Cologne, Cologne, Germany
| | - Gunter Rappl
- Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany.,Department I of Internal Medicine, University Hospital Cologne, Cologne, Germany
| | | | - Astrid C Schauss
- Cluster of Excellence, Cellular Stress Response in Aging-Related Diseases, Core Facility Imaging, University of Cologne, Cologne, Germany
| | - Christian Jüngst
- Cluster of Excellence, Cellular Stress Response in Aging-Related Diseases, Core Facility Imaging, University of Cologne, Cologne, Germany
| | - Marcus Krüger
- Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany.,Cluster of Excellence, Cellular Stress Response in Aging-Related Diseases, Core Facility Proteomics, University of Cologne, Cologne, Germany.,Institute for Genetics, University of Cologne, Cologne, Germany
| | - Sven Dressler
- Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Tomoyuki Nakamura
- Department of Pharmacology, Kansai Medical University, Osaka, Japan; and
| | - Frank Wempe
- Department of Molecular Hematology, University of Frankfurt Medical School, Frankfurt am Main, Germany
| | - Miguel A Alejandre Alcázar
- Department of Pediatrics and Adolescent Medicine, Medical Faculty, University of Cologne, Cologne, Germany
| | - Anja Sterner-Kock
- Center for Experimental Medicine, Medical Faculty, University of Cologne, Cologne, Germany;
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30
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Lu J, Liu Q, Wang L, Tu W, Chu H, Ding W, Jiang S, Ma Y, Shi X, Pu W, Zhou X, Jin L, Wang J, Wu W. Increased expression of latent TGF-β-binding protein 4 affects the fibrotic process in scleroderma by TGF-β/SMAD signaling. J Transl Med 2017; 97:591-601. [PMID: 28263294 DOI: 10.1038/labinvest.2017.20] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 01/03/2017] [Accepted: 01/13/2017] [Indexed: 01/06/2023] Open
Abstract
Scleroderma is a fibrosis-related disorder characterized by cutaneous and internal organ fibrosis, and excessive collagen deposition in extracellular matrix (ECM) is a major cause of fibrosis. Transforming growth factor-β (TGF-β)/SMAD signaling has a central role in the pathogenesis of fibrosis by inducing abnormal collagen accumulation in ECM, and latent TGF-β-binding protein 4 (LTBP-4) affects the secretion of latent TGF-β to ECM. A previous study indicated that bleomycin (BLM) treatment increased LTBP-4 expression in lung fibroblasts of Thy-1 knockout mice with lung fibrosis, and LTBP-4 further promoted TGF-β bioavailability as well as SMAD3 phosphorylation. However, the expression and function of LTBP-4 in human scleroderma remain unclear. We aimed to investigate the potential role of LTBP-4 in scleroderma through clinical, in vivo and in vitro studies. LTBP-4 and TGF-β expressions were significantly upregulated in systemic scleroderma (SSc) patients' plasma compared with normal controls (LTBP-4, 1,215±100.2 vs 542.8±41.7 ng/ml, P<0.0001; TGF-β, 1.5±0.2 vs 0.7±0.1 ng/ml, P=0.0031), while no significant difference was found between localized scleroderma (LSc) and normal controls. The plasma concentrations of LTBP-4 and TGF-β were even higher in SSc patients with lung fibrosis (LTBP-4, 1462± 137.3 vs 892.8±113.4 ng/ml, P=0.0037; TGF-β, 2.0±0.4 vs 0.9±0.2 ng/ml, P=0.0212) and esophagus involvement (1390±134.4 vs 940.7±127.0 ng/ml, P=0.0269; TGF-β, 1.9±0.3 vs 0.9±0.2 ng/ml, P=0.0426). The area under receiver operating characteristics (ROC) curve of LTBP-4 was 0.86. Immunohistochemistry measurement also demonstrated a higher LTBP-4 expression in sclerotic skin tissue of LSc and SSc compared with normal controls. More positive fibroblasts were also found in BLM-induced scleroderma mouse model than the saline-treated group. In in vitro studies, knockdown of LTBP-4 in SSc skin fibroblasts prominently reduced downstream COL1A1, COL1A2, and COL3A1 mRNA level by 84%, 82%, and 43%, respectively, and other fibrosis-related genes' expression were also decreased. Furthermore, extracellular TGF-β level and the SMAD2/3 phosphorylation were inhibited through LTBP-4 knockdown treatment, suggesting that the knockdown of LTBP-4 reduced the collagen expression through TGF-β/SMAD signaling pathway. Taken together, these data suggest that LTBP-4 affects fibrotic process in scleroderma, and the high expression of LTBP-4 in SSc plasma may serve as a clinical biomarker in diagnosing this disease. In addition, this study also lays the theoretical foundation for targeting LTBP-4 as treatment of scleroderma.
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Affiliation(s)
- Jiaying Lu
- Department of Dermatology, Huashan Hospital, Fudan University, Shanghai, China
| | - Qingmei Liu
- Department of Dermatology, Huashan Hospital, Fudan University, Shanghai, China.,State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Lei Wang
- Division of Rheumatology, Shanghai TCM-integrated Hospital, Shanghai, China
| | - Wenzhen Tu
- Division of Rheumatology, Shanghai TCM-integrated Hospital, Shanghai, China
| | - Haiyan Chu
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Weifeng Ding
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Shuai Jiang
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Yanyun Ma
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Xiangguang Shi
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Weilin Pu
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Xiaodong Zhou
- University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Li Jin
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Jiucun Wang
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China.,Institute of Rheumatology, Immunology and Allergy, Fudan University, Shanghai, China
| | - Wenyu Wu
- Department of Dermatology, Huashan Hospital, Fudan University, Shanghai, China
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31
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Brauchle E, Bauer H, Fernes P, Zuk A, Schenke-Layland K, Sengle G. Raman microspectroscopy as a diagnostic tool for the non-invasive analysis of fibrillin-1 deficiency in the skin and in the in vitro skin models. Acta Biomater 2017; 52:41-48. [PMID: 27956365 DOI: 10.1016/j.actbio.2016.12.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 12/06/2016] [Accepted: 12/07/2016] [Indexed: 10/20/2022]
Abstract
Fibrillin microfibrils and elastic fibers are critical determinants of elastic tissues where they define as tissue-specific architectures vital mechanical properties such as pliability and elastic recoil. Fibrillin microfibrils also facilitate elastic fiber formation and support the association of epithelial cells with the interstitial matrix. Mutations in fibrillin-1 (FBN1) are causative for the Marfan syndrome, a congenital multisystem disorder characterized by progressive deterioration of the fibrillin microfibril/ elastic fiber architecture in the cardiovascular, musculoskeletal, ocular, and dermal system. In this study, we utilized Raman microspectroscopy in combination with principal component analysis (PCA) to analyze the molecular consequences of fibrillin-1 deficiency in skin of a mouse model (GT8) of Marfan syndrome. In addition, full-thickness skin models incorporating murine wild-type and Fbn1GT8/GT8 fibroblasts as well as human HaCaT keratinocytes were generated and analyzed. Skin models containing GT8 fibroblasts showed an altered epidermal morphology when compared to wild-type models indicating a new role for fibrillin-1 in dermal-epidermal crosstalk. Obtained Raman spectra together with PCA allowed to discriminate between healthy and deficient microfibrillar networks in murine dermis and skin models. Interestingly, results obtained from GT8 dermis and skin models showed similar alterations in molecular signatures triggered by fibrillin-1 deficiency such as amide III vibrations and decreased levels of glycan vibrations. Overall, this study indicates that Raman microspectroscopy has the potential to analyze subtle changes in fibrillin-1 microfibrils and elastic fiber networks. Therefore Raman microspectroscopy may be utilized as a non-invasive and sensitive diagnostic tool to identify connective tissue disorders and monitor their disease progression. STATEMENT OF SIGNIFICANCE Mutations in building blocks of the fibrillin microfibril/ elastic fiber network manifest in disease conditions such as aneurysms, emphysema or lax skin. Understanding how structural changes induced by fibrillin-1 mutation impact the architecture of fibrillin microfibrils, which then translates into an altered activation state of targeted growth factors, represents a huge challenge in elucidating the genotype-phenotype correlations in connective tissue disorders such as Marfan syndrome. This study shows that Raman microspectroscopy is able to reveal structural changes in fibrillin-1 microfibrils and elastic fiber networks and to discriminate between normal and diseased networks in vivo and in vitro. Therefore Raman microspectroscopy may be utilized as a non-invasive and sensitive diagnostic tool to identify connective tissue disorders and monitor their disease progression.
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32
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Gkogkolou P, Hildebrandt K, Broekaert S, Metze D, Sengle G, Böhm M. Cutis laxa acquisita: novel insights into impaired elastic fibre regeneration. Br J Dermatol 2017; 176:832-835. [DOI: 10.1111/bjd.15196] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- P. Gkogkolou
- Department of Dermatology; University of Münster; Münster Germany
| | - K. Hildebrandt
- Center for Biochemistry; Medical Faculty; University of Cologne; Cologne Germany
- Center for Molecular Medicine Cologne (CMMC); University of Cologne; Cologne Germany
| | - S. Broekaert
- Department of Dermatology; University of Münster; Münster Germany
| | - D. Metze
- Department of Dermatology; University of Münster; Münster Germany
| | - G. Sengle
- Center for Biochemistry; Medical Faculty; University of Cologne; Cologne Germany
- Center for Molecular Medicine Cologne (CMMC); University of Cologne; Cologne Germany
| | - M. Böhm
- Department of Dermatology; University of Münster; Münster Germany
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33
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Tomasovic A, Kurrle N, Wempe F, De-Zolt S, Scheibe S, Koli K, Serchinger M, Schnütgen F, Sürün D, Sterner-Kock A, Weissmann N, von Melchner H. Ltbp4 regulates Pdgfrβ expression via TGFβ-dependent modulation of Nrf2 transcription factor function. Matrix Biol 2016; 59:109-120. [PMID: 27645114 DOI: 10.1016/j.matbio.2016.09.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 09/07/2016] [Accepted: 09/11/2016] [Indexed: 10/21/2022]
Abstract
Latent transforming growth factor beta binding protein 4 (LTBP4) belongs to the fibrillin/LTBP family of proteins and plays an important role as a structural component of extracellular matrix (ECM) and local regulator of TGFβ signaling. We have previously reported that Ltbp4S knock out mice (Ltbp4S-/-) develop centrilobular emphysema reminiscent of late stage COPD, which could be partially rescued by inactivating the antioxidant protein Sestrin 2 (Sesn2). More recent studies showed that Sesn2 knock out mice upregulate Pdgfrβ-controlled alveolar maintenance programs that protect against cigarette smoke induced pulmonary emphysema. Based on this, we hypothesized that the emphysema of Ltbp4S-/- mice is primarily caused by defective Pdgfrβ signaling. Here we show that LTBP4 induces Pdgfrβ signaling by inhibiting the antioxidant Nrf2/Keap1 pathway in a TGFβ-dependent manner. Overall, our data identified Ltbp4 as a major player in lung remodeling and injury repair.
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Affiliation(s)
- Ana Tomasovic
- Department of Molecular Hematology, Goethe University Medical School, D-60590 Frankfurt am Main, Germany
| | - Nina Kurrle
- Department of Molecular Hematology, Goethe University Medical School, D-60590 Frankfurt am Main, Germany
| | - Frank Wempe
- Department of Molecular Hematology, Goethe University Medical School, D-60590 Frankfurt am Main, Germany
| | - Silke De-Zolt
- Department of Molecular Hematology, Goethe University Medical School, D-60590 Frankfurt am Main, Germany
| | - Susan Scheibe
- Excellence Cluster Cardiopulmonary System (ECCPS), Justus-Liebig-University Giessen, Department of Internal Medicine, Universities of Giessen and Marburg Lung Center (UGMLC), D-35392 Giessen, Germany
| | - Katri Koli
- Research Programs Unit and Transplantation Laboratory, Haartman Institute, University of Helsinki, 00014, Helsinki, Finland
| | - Martin Serchinger
- Department of Molecular Hematology, Goethe University Medical School, D-60590 Frankfurt am Main, Germany
| | - Frank Schnütgen
- Department of Molecular Hematology, Goethe University Medical School, D-60590 Frankfurt am Main, Germany
| | - Duran Sürün
- Department of Molecular Hematology, Goethe University Medical School, D-60590 Frankfurt am Main, Germany
| | - Anja Sterner-Kock
- Center for Experimental Medicine, Medical Faculty, University of Cologne, 50931 Cologne, Germany
| | - Norbert Weissmann
- Excellence Cluster Cardiopulmonary System (ECCPS), Justus-Liebig-University Giessen, Department of Internal Medicine, Universities of Giessen and Marburg Lung Center (UGMLC), D-35392 Giessen, Germany
| | - Harald von Melchner
- Department of Molecular Hematology, Goethe University Medical School, D-60590 Frankfurt am Main, Germany.
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34
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Bultmann-Mellin I, Essers J, van Heijingen PM, von Melchner H, Sengle G, Sterner-Kock A. Function of Ltbp-4L and fibulin-4 in survival and elastogenesis in mice. Dis Model Mech 2016; 9:1367-1374. [PMID: 27585882 PMCID: PMC5117228 DOI: 10.1242/dmm.026005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 08/15/2016] [Indexed: 12/18/2022] Open
Abstract
LTBP-4L and LTBP-4S are two isoforms of the extracellular matrix protein latent-transforming growth factor beta-binding protein 4 (LTBP-4). The mutational inactivation of both isoforms causes autosomal recessive cutis laxa type 1C (ARCL1C) in humans and an ARCL1C-like phenotype in Ltbp4-/- mice, both characterized by high postnatal mortality and severely affected elastogenesis. However, genetic data in mice suggest isoform-specific functions for Ltbp-4 because Ltbp4S-/- mice, solely expressing Ltbp-4L, survive to adulthood. This clearly suggests a requirement of Ltbp-4L for postnatal survival. A major difference between Ltbp4S-/- and Ltbp4-/- mice is the matrix incorporation of fibulin-4 (a key factor for elastogenesis; encoded by the Efemp2 gene), which is normal in Ltbp4S-/- mice, whereas it is defective in Ltbp4-/- mice, suggesting that the presence of Ltbp-4L might be required for this process. To investigate the existence of a functional interaction between Ltbp-4L and fibulin-4, we studied the consequences of fibulin-4 deficiency in mice only expressing Ltbp-4L. Resulting Ltbp4S-/-;Fibulin-4R/R mice showed a dramatically reduced lifespan compared to Ltbp4S-/- or Fibulin-4R/R mice, which survive to adulthood. This dramatic reduction in survival of Ltbp4S-/-;Fibulin-4R/R mice correlates with severely impaired elastogenesis resulting in defective alveolar septation and distal airspace enlargement in lung, and increased aortic wall thickness with severely fragmented elastic lamellae. Additionally, Ltbp4S-/-;Fibulin-4R/R mice suffer from aortic aneurysm formation combined with aortic tortuosity, in contrast to Ltbp4S-/- or Fibulin-4R/R mice. Together, in accordance with our previous biochemical findings of a physical interaction between Ltbp-4L and fibulin-4, these novel in vivo data clearly establish a functional link between Ltbp-4L and fibulin-4 as a crucial molecular requirement for survival and elastogenesis in mice.
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Affiliation(s)
- Insa Bultmann-Mellin
- Center for Experimental Medicine, Medical Faculty, University of Cologne, 50931 Cologne, Germany
| | - Jeroen Essers
- Department of Molecular Genetics, Cancer Genomics Centre, Erasmus MC, 3015 CN Rotterdam, The Netherlands.,Department of Radiation Oncology, Erasmus MC, 3015 CN Rotterdam, The Netherlands.,Department of Vascular Surgery, Erasmus MC, 3015 CN Rotterdam, The Netherlands
| | - Paula M van Heijingen
- Department of Molecular Genetics, Cancer Genomics Centre, Erasmus MC, 3015 CN Rotterdam, The Netherlands
| | - Harald von Melchner
- Department of Molecular Hematology, University of Frankfurt Medical School, 60590 Frankfurt am Main, Germany
| | - Gerhard Sengle
- Center for Biochemistry, Medical Faculty, University of Cologne, 50931 Cologne, Germany.,Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Anja Sterner-Kock
- Center for Experimental Medicine, Medical Faculty, University of Cologne, 50931 Cologne, Germany
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Overexpression of Latent TGFβ Binding Protein 4 in Muscle Ameliorates Muscular Dystrophy through Myostatin and TGFβ. PLoS Genet 2016; 12:e1006019. [PMID: 27148972 PMCID: PMC4858180 DOI: 10.1371/journal.pgen.1006019] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2015] [Accepted: 04/08/2016] [Indexed: 01/06/2023] Open
Abstract
Latent TGFβ binding proteins (LTBPs) regulate the extracellular availability of latent TGFβ. LTBP4 was identified as a genetic modifier of muscular dystrophy in mice and humans. An in-frame insertion polymorphism in the murine Ltbp4 gene associates with partial protection against muscular dystrophy. In humans, nonsynonymous single nucleotide polymorphisms in LTBP4 associate with prolonged ambulation in Duchenne muscular dystrophy. To better understand LTBP4 and its role in modifying muscular dystrophy, we created transgenic mice overexpressing the protective murine allele of LTBP4 specifically in mature myofibers using the human skeletal actin promoter. Overexpression of LTBP4 protein was associated with increased muscle mass and proportionally increased strength compared to age-matched controls. In order to assess the effects of LTBP4 in muscular dystrophy, LTBP4 overexpressing mice were bred to mdx mice, a model of Duchenne muscular dystrophy. In this model, increased LTBP4 led to greater muscle mass with proportionally increased strength, and decreased fibrosis. The increase in muscle mass and reduction in fibrosis were similar to what occurs when myostatin, a related TGFβ family member and negative regulator of muscle mass, was deleted in mdx mice. Supporting this, we found that myostatin forms a complex with LTBP4 and that overexpression of LTBP4 led to a decrease in myostatin levels. LTBP4 also interacted with TGFβ and GDF11, a protein highly related to myostatin. These data identify LTBP4 as a multi-TGFβ family ligand binding protein with the capacity to modify muscle disease through overexpression. Muscular dystrophy is a genetic disease with muscle weakness, replacement of muscle tissue with fibrosis, and premature death. The gene for latent TGFβ binding protein 4 (LTBP4) was previously found to modify muscular dystrophy in both mice and humans with variants that confer protection from disease. In order to better understand this modifier gene, the protective version of LTBP4 was overexpressed specifically in the skeletal muscles of mice. Increased levels of LTBP4 protein resulted in increased muscle mass. Overexpression of LTBP4 in a mouse model of Duchenne muscular dystrophy alleviated many disease-associated features producing larger muscles, increased strength, and reduced fibrosis in muscle. LTBP4 formed a complex with myostatin, a protein that when inhibited leads to muscle growth. In LTBP4-overexpressing mice, active myostatin protein was decreased. This study shows that LTBP4 modifies muscular dystrophy based on its ability to scaffold and regulate multiple TGFβ family members including myostatin.
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