1
|
Neupane S, Williamson DB, Roth RA, Halabi CM, Haltiwanger RS, Holdener BC. Poglut2/3 double knockout in mice results in neonatal lethality with reduced levels of fibrillin in lung tissues. J Biol Chem 2024; 300:107445. [PMID: 38844137 PMCID: PMC11261140 DOI: 10.1016/j.jbc.2024.107445] [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: 03/24/2024] [Revised: 05/08/2024] [Accepted: 05/17/2024] [Indexed: 06/30/2024] Open
Abstract
Fibrillin microfibrils play a critical role in the formation of elastic fibers, tissue/organ development, and cardiopulmonary function. These microfibrils not only provide structural support and flexibility to tissues, but they also regulate growth factor signaling through a plethora of microfibril-binding proteins in the extracellular space. Mutations in fibrillins are associated with human diseases affecting cardiovascular, pulmonary, skeletal, and ocular systems. Fibrillins consist of up to 47 epidermal growth factor-like repeats, of which more than half are modified by protein O-glucosyltransferase 2 (POGLUT2) and/or POGLUT3. Loss of these modifications reduces secretion of N-terminal fibrillin constructs overexpressed in vitro. Here, we investigated the role of POGLUT2 and POGLUT3 in vivo using a Poglut2/3 double knockout (DKO) mouse model. Blocking O-glucosylation caused neonatal death with skeletal, pulmonary, and eye defects reminiscent of fibrillin/elastin mutations. Proteomic analyses of DKO dermal fibroblast medium and extracellular matrix provided evidence that fibrillins were more sensitive to loss of O-glucose compared to other POGLUT2/3 substrates. This conclusion was supported by immunofluorescent analyses of late gestation DKO lungs where FBN levels were reduced and microfibrils appeared fragmented in the pulmonary arteries and veins, bronchioles, and developing saccules. Defects in fibrillin microfibrils likely contributed to impaired elastic fiber formation and histological changes observed in DKO lung blood vessels, bronchioles, and saccules. Collectively, these results highlight the importance of POGLUT2/3-mediated O-glucosylation in vivo and open the possibility that O-glucose modifications on fibrillin influence microfibril assembly and or protein interactions in the ECM environment.
Collapse
Affiliation(s)
- Sanjiv Neupane
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York, USA
| | - Daniel B Williamson
- Complex Carbohydrate Research Center, Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Robyn A Roth
- Division of Nephrology, Department of Pediatrics, Washington University School of Medicine, St Louis, Missouri, USA
| | - Carmen M Halabi
- Division of Nephrology, Department of Pediatrics, Washington University School of Medicine, St Louis, Missouri, USA
| | - Robert S Haltiwanger
- Complex Carbohydrate Research Center, Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA.
| | - Bernadette C Holdener
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York, USA.
| |
Collapse
|
2
|
Yang-Jensen KC, Jørgensen SM, Chuang CY, Davies MJ. Modification of extracellular matrix proteins by oxidants and electrophiles. Biochem Soc Trans 2024; 52:1199-1217. [PMID: 38778764 DOI: 10.1042/bst20230860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 04/24/2024] [Accepted: 05/08/2024] [Indexed: 05/25/2024]
Abstract
The extracellular matrix (ECM) is critical to biological architecture and determines cellular properties, function and activity. In many situations it is highly abundant, with collagens and elastin being some of the most abundant proteins in mammals. The ECM comprises of multiple different protein species and sugar polymers, with both different isoforms and post-translational modifications (PTMs) providing a large variety of microenvironments that play a key role in determining tissue structure and health. A number of the PTMs (e.g. cross-links) present in the ECM are critical to integrity and function, whereas others are deleterious to both ECM structure and associated cells. Modifications induced by reactive oxidants and electrophiles have been reported to accumulate in some ECM with increasing age. This accumulation can be exacerbated by disease, and in particular those associated with acute or chronic inflammation, obesity and diabetes. This is likely to be due to higher fluxes of modifying agents in these conditions. In this focused review, the role and effects of oxidants and other electrophiles on ECM are discussed, with a particular focus on the artery wall and atherosclerotic cardiovascular disease. Modifications generated on ECM components are reviewed, together with the effects of these species on cellular properties including adhesion, proliferation, migration, viability, metabolic activity, gene expression and phenotype. Increasing data indicates that ECM modifications are both prevalent in human and mammalian tissues and play an important role in disease development and progression.
Collapse
Affiliation(s)
- Karen C Yang-Jensen
- Department of Biomedical Sciences, Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Sara M Jørgensen
- Department of Biomedical Sciences, Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Christine Y Chuang
- Department of Biomedical Sciences, Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Michael J Davies
- Department of Biomedical Sciences, Panum Institute, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
3
|
Lau K, Reichheld S, Xian M, Sharpe SJ, Cerruti M. Directed Assembly of Elastic Fibers via Coacervate Droplet Deposition on Electrospun Templates. Biomacromolecules 2024; 25:3519-3531. [PMID: 38742604 DOI: 10.1021/acs.biomac.4c00180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Elastic fibers provide critical elasticity to the arteries, lungs, and other organs. Elastic fiber assembly is a process where soluble tropoelastin is coacervated into liquid droplets, cross-linked, and deposited onto and into microfibrils. While much progress has been made in understanding the biology of this process, questions remain regarding the timing of interactions during assembly. Furthermore, it is unclear to what extent fibrous templates are needed to guide coacervate droplets into the correct architecture. The organization and shaping of coacervate droplets onto a fiber template have never been previously modeled or employed as a strategy for shaping elastin fiber materials. Using an in vitro system consisting of elastin-like polypeptides (ELPs), genipin cross-linker, electrospun polylactic-co-glycolic acid (PLGA) fibers, and tannic acid surface coatings for fibers, we explored ELP coacervation, cross-linking, and deposition onto fiber templates. We demonstrate that integration of coacervate droplets into a fibrous template is primarily influenced by two factors: (1) the balance of coacervation and cross-linking and (2) the surface energy of the fiber templates. The success of this integration affects the mechanical properties of the final fiber network. Our resulting membrane materials exhibit highly tunable morphologies and a range of elastic moduli (0.8-1.6 MPa) comparable to native elastic fibers.
Collapse
Affiliation(s)
- Kirklann Lau
- Department of Mining and Materials Engineering, McGill University, 3610 University Street, Wong Building 2250, Montreal, Quebec H3A 0C5, Canada
| | - Sean Reichheld
- Molecular Medicine, Hospital for Sick Children, Peter Gilgan Center for Research and Learning, 686 Bay Street, Room 20.9714, Toronto, Ontario M5G 1X8, Canada
| | - Mingqian Xian
- Department of Mining and Materials Engineering, McGill University, 3610 University Street, Wong Building 2250, Montreal, Quebec H3A 0C5, Canada
| | - Simon J Sharpe
- Molecular Medicine, Hospital for Sick Children, Peter Gilgan Center for Research and Learning, 686 Bay Street, Room 20.9714, Toronto, Ontario M5G 1X8, Canada
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Medical Sciences Building, Room 5207, Toronto, Ontario M5S 1A8, Canada
| | - Marta Cerruti
- Department of Mining and Materials Engineering, McGill University, 3610 University Street, Wong Building 2250, Montreal, Quebec H3A 0C5, Canada
| |
Collapse
|
4
|
Summers KM. Genetic models of fibrillinopathies. Genetics 2024; 226:iyad189. [PMID: 37972149 PMCID: PMC11021029 DOI: 10.1093/genetics/iyad189] [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: 09/01/2023] [Accepted: 10/16/2023] [Indexed: 11/19/2023] Open
Abstract
The fibrillinopathies represent a group of diseases in which the 10-12 nm extracellular microfibrils are disrupted by genetic variants in one of the genes encoding fibrillin molecules, large glycoproteins of the extracellular matrix. The best-known fibrillinopathy is Marfan syndrome, an autosomal dominant condition affecting the cardiovascular, ocular, skeletal, and other systems, with a prevalence of around 1 in 3,000 across all ethnic groups. It is caused by variants of the FBN1 gene, encoding fibrillin-1, which interacts with elastin to provide strength and elasticity to connective tissues. A number of mouse models have been created in an attempt to replicate the human phenotype, although all have limitations. There are also natural bovine models and engineered models in pig and rabbit. Variants in FBN2 encoding fibrillin-2 cause congenital contractural arachnodactyly and mouse models for this condition have also been produced. In most animals, including birds, reptiles, and amphibians, there is a third fibrillin, fibrillin-3 (FBN3 gene) for which the creation of models has been difficult as the gene is degenerate and nonfunctional in mice and rats. Other eukaryotes such as the nematode C. elegans and zebrafish D. rerio have a gene with some homology to fibrillins and models have been used to discover more about the function of this family of proteins. This review looks at the phenotype, inheritance, and relevance of the various animal models for the different fibrillinopathies.
Collapse
Affiliation(s)
- Kim M Summers
- Mater Research Institute-University of Queensland, Translational Research Institute, Woolloongabba QLD 4102, Australia
| |
Collapse
|
5
|
Pan Y, Liu Z, Zhang H. Research progress of lens zonules. ADVANCES IN OPHTHALMOLOGY PRACTICE AND RESEARCH 2023; 3:80-85. [PMID: 37846380 PMCID: PMC10577871 DOI: 10.1016/j.aopr.2023.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/23/2023] [Accepted: 02/23/2023] [Indexed: 10/18/2023]
Abstract
Background The lens zonule, a circumferential system of fibres connecting the ciliary body to the lens, is responsible for centration of the lens. The structural, functional, and positional abnormalities of the zonular apparatus can lead to the abnormality of the intraocular structure, presenting a significant challenge to cataract surgery. Main text The lens zonule is the elaborate system of extracellular fibers, which not only centers the lens in the eye but also plays an important role in accommodation and lens immunity, maintains the shape of the lens, and corrects spherical aberration. The zonules may directly participate in the formation of cataract via the immune mechanism. Abnormal zonular fibers that affect the position and shape of the lens may play an important role in the pathogenesis of angle closure disease and increase the complexity of the surgery. Capsular tension rings and related endocapsular devices are used to provide sufficient capsular bag stabilization and ensure the safety of cataract surgery procedures. Better preoperative and intraoperative evaluation methods for zonules are needed for clinicians. Conclusions The microstructure, biomechanical properties, and physiological functions of the lens zonules help us to better understand the pathogenesis of cataract and glaucoma, facilitating the development of safer surgical procedures for cataract. Further studies are needed to carefully analyze the structure-function relationship of the zonular apparatus to explore new treatment strategies for cataract and glaucoma.
Collapse
Affiliation(s)
- Yingying Pan
- Department of Ophthalmology, Shandong Provincial Hospital, Shandong University, Jinan, China
| | - Zhaoqiang Liu
- Department of Ophthalmology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Han Zhang
- Department of Ophthalmology, Shandong Provincial Hospital, Shandong University, Jinan, China
| |
Collapse
|
6
|
Șulea CM, Mártonfalvi Z, Csányi C, Haluszka D, Pólos M, Ágg B, Stengl R, Benke K, Szabolcs Z, Kellermayer MSZ. Nanoscale Structural Comparison of Fibrillin-1 Microfibrils Isolated from Marfan and Non-Marfan Syndrome Human Aorta. Int J Mol Sci 2023; 24:ijms24087561. [PMID: 37108724 PMCID: PMC10145871 DOI: 10.3390/ijms24087561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 04/18/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
Fibrillin-1 microfibrils are essential elements of the extracellular matrix serving as a scaffold for the deposition of elastin and endowing connective tissues with tensile strength and elasticity. Mutations in the fibrillin-1 gene (FBN1) are linked to Marfan syndrome (MFS), a systemic connective tissue disorder that, besides other heterogeneous symptoms, usually manifests in life-threatening aortic complications. The aortic involvement may be explained by a dysregulation of microfibrillar function and, conceivably, alterations in the microfibrils' supramolecular structure. Here, we present a nanoscale structural characterization of fibrillin-1 microfibrils isolated from two human aortic samples with different FBN1 gene mutations by using atomic force microscopy, and their comparison with microfibrillar assemblies purified from four non-MFS human aortic samples. Fibrillin-1 microfibrils displayed a characteristic "beads-on-a-string" appearance. The microfibrillar assemblies were investigated for bead geometry (height, length, and width), interbead region height, and periodicity. MFS fibrillin-1 microfibrils had a slightly higher mean bead height, but the bead length and width, as well as the interbead height, were significantly smaller in the MFS group. The mean periodicity varied around 50-52 nm among samples. The data suggest an overall thinner and presumably more frail structure for the MFS fibrillin-1 microfibrils, which may play a role in the development of MFS-related aortic symptomatology.
Collapse
Affiliation(s)
- Cristina M Șulea
- Department of Biophysics and Radiation Biology, Semmelweis University, 1094 Budapest, Hungary
- Heart and Vascular Center, Semmelweis University, 1122 Budapest, Hungary
- Hungarian Marfan Foundation, 1122 Budapest, Hungary
| | - Zsolt Mártonfalvi
- Department of Biophysics and Radiation Biology, Semmelweis University, 1094 Budapest, Hungary
| | - Csilla Csányi
- Department of Biophysics and Radiation Biology, Semmelweis University, 1094 Budapest, Hungary
| | - Dóra Haluszka
- Department of Biophysics and Radiation Biology, Semmelweis University, 1094 Budapest, Hungary
| | - Miklós Pólos
- Heart and Vascular Center, Semmelweis University, 1122 Budapest, Hungary
- Hungarian Marfan Foundation, 1122 Budapest, Hungary
| | - Bence Ágg
- Heart and Vascular Center, Semmelweis University, 1122 Budapest, Hungary
- Hungarian Marfan Foundation, 1122 Budapest, Hungary
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, 1089 Budapest, Hungary
| | - Roland Stengl
- Heart and Vascular Center, Semmelweis University, 1122 Budapest, Hungary
- Hungarian Marfan Foundation, 1122 Budapest, Hungary
| | - Kálmán Benke
- Heart and Vascular Center, Semmelweis University, 1122 Budapest, Hungary
- Hungarian Marfan Foundation, 1122 Budapest, Hungary
- Department of Cardiac Surgery, University Hospital Halle (Saale), 06120 Halle (Saale), Germany
| | - Zoltán Szabolcs
- Heart and Vascular Center, Semmelweis University, 1122 Budapest, Hungary
- Hungarian Marfan Foundation, 1122 Budapest, Hungary
| | - Miklós S Z Kellermayer
- Department of Biophysics and Radiation Biology, Semmelweis University, 1094 Budapest, Hungary
| |
Collapse
|
7
|
Summers KM, Bush SJ, Davis MR, Hume DA, Keshvari S, West JA. Fibrillin-1 and asprosin, novel players in metabolic syndrome. Mol Genet Metab 2023; 138:106979. [PMID: 36630758 DOI: 10.1016/j.ymgme.2022.106979] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 12/13/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022]
Abstract
Fibrillin-1 is a major component of the extracellular microfibrils, where it interacts with other extracellular matrix proteins to provide elasticity to connective tissues, and regulates the bioavailability of TGFβ family members. A peptide consisting of the C-terminal 140 amino acids of fibrillin-1 has recently been identified as a glucogenic hormone, secreted from adipose tissue during fasting and targeting the liver to release glucose. This fragment, called asprosin, also signals in the hypothalamus to stimulate appetite. Asprosin levels are correlated with many of the pathologies indicative of metabolic syndrome, including insulin resistance and obesity. Previous studies and reviews have addressed the therapeutic potential of asprosin as a target in obesity, diabetes and related conditions without considering mechanisms underlying the relationship between generation of asprosin and expression of the much larger fibrillin-1 protein. Profibrillin-1 undergoes obligatory cleavage at the cell surface as part of its assembly into microfibrils, producing the asprosin peptide as well as mature fibrillin-1. Patterns of FBN1 mRNA expression are inconsistent with the necessity for regulated release of asprosin. The asprosin peptide may be protected from degradation in adipose tissue. We present evidence for an alternative possibility, that asprosin mRNA is generated independently from an internal promoter within the 3' end of the FBN1 gene, which would allow for regulation independent of fibrillin-synthesis and is more economical of cellular resources. The discovery of asprosin opened exciting possibilities for treatment of metabolic syndrome related conditions, but there is much to be understood before such therapies could be introduced into the clinic.
Collapse
Affiliation(s)
- Kim M Summers
- Mater Research Institute-University of Queensland, Translational Research Institute, 37 Kent St, Woolloongabba, Queensland 4102, Australia.
| | - Stephen J Bush
- Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DS, United Kingdom.
| | - Margaret R Davis
- The Roslin Institute, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, United Kingdom
| | - David A Hume
- Mater Research Institute-University of Queensland, Translational Research Institute, 37 Kent St, Woolloongabba, Queensland 4102, Australia.
| | - Sahar Keshvari
- Mater Research Institute-University of Queensland, Translational Research Institute, 37 Kent St, Woolloongabba, Queensland 4102, Australia.
| | - Jennifer A West
- Faculty of Medicine, The University of Queensland, Mayne Medical Building, 288 Herston Road, Herston, Queensland 4006, Australia.
| |
Collapse
|
8
|
Wareham LK, Whitener AE, Wu HJ, Wu SY, Mchaourab HS, Mortlock DP, Kuchtey RW, Kuchtey J. Adamts10 controls transforming growth factor β family signaling that contributes to retinal ganglion cell development. Front Mol Biosci 2022; 9:989851. [PMID: 36148008 PMCID: PMC9485804 DOI: 10.3389/fmolb.2022.989851] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 08/05/2022] [Indexed: 12/14/2022] Open
Abstract
Although mutations in ADAMTS10 have long been known to cause autosomal recessive Weill-Marchesani Syndrome which is characterized by short stature and ocular abnormalities, more recent work has shown that certain mutations in ADAMTS10 cause glaucoma in dogs. In humans, glaucoma is the leading cause of irreversible vision loss that affects tens of millions of people world-wide. Vision loss in glaucoma is a result of neurodegeneration of retinal ganglion cells that form the inner-most layer of the retina and whose axons form the optic nerve which relays visual information to the brain. ADAMTS10 contributes to the formation of microfibrils which sequester latent transforming growth factor β (TGFβ). Among its many biological functions, TGFβ promotes the development of retinal ganglion cells and is also known to play other roles in glaucoma pathogenesis. The aim of this study was to test the hypothesis that ADAMTS10 plays a role in retinal ganglion cell development through regulation of TGFβ signaling. To this end, Adamts10 expression was targeted for reduction in zebrafish embryos carrying either a fluorescent reporter that labels retinal ganglion cells, or a fluorescent reporter of pSmad3-mediated TGFβ family signaling. Loss of adamts10 function in zebrafish embryos reduced retinal ganglion cell reporter fluorescence and prevented formation of an ordered retinal ganglion cell layer. Targeting adamts10 expression also drastically reduced constitutive TGFβ signaling in the eye. Direct inhibition of the TGFβ receptor reduced retinal ganglion cell reporter fluorescence similar to the effect of targeting adamts10 expression. These findings unveil a previously unknown role for Adamts10 in retinal ganglion cell development and suggest that the developmental role of Adamts10 is mediated by active TGFβ family signaling. In addition, our results show for the first time that Adamts10 is necessary for pSmad3-mediated constitutive TGFβ family signaling.
Collapse
Affiliation(s)
- Lauren K. Wareham
- Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Amy E. Whitener
- Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Hang-Jing Wu
- Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Shu-Yu Wu
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, United States
| | - Hassane S. Mchaourab
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, United States
| | - Douglas P. Mortlock
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, United States
| | - Rachel W. Kuchtey
- Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States,Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, United States
| | - John Kuchtey
- Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States,*Correspondence: John Kuchtey,
| |
Collapse
|
9
|
Pathania S, Khan MI, Bandyopadhyay S, Singh SS, Rani K, Parashar TR, Jayaram J, Mishra PR, Srivastava A, Mathur S, Hari S, Vanamail P, Hariprasad G. iTRAQ proteomics of sentinel lymph nodes for identification of extracellular matrix proteins to flag metastasis in early breast cancer. Sci Rep 2022; 12:8625. [PMID: 35599267 PMCID: PMC9124668 DOI: 10.1038/s41598-022-12352-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 05/03/2022] [Indexed: 12/24/2022] Open
Abstract
Patients with early breast cancer are affected by metastasis to axillary lymph nodes. Metastasis to these nodes is crucial for staging and quality of surgery. Sentinel Lymph Node Biopsy that is currently used to assess lymph node metastasis is not effective. This necessitates identification of biomarkers that can flag metastasis. Early stage breast cancer patients were recruited. Surgical resection of breast was followed by identification of sentinel lymph nodes. Fresh frozen section biopsy was used to assign metastatic and non-metastatic sentinel lymph nodes. Discovery phase included iTRAQ proteomics coupled with mass spectrometric analysis to identify differentially expressed proteins. Data is available via ProteomeXchange with identifier PXD027668. Validation was done by bioinformatic analysis and ELISA. There were 2398 unique protein groups and 109 differentially expressed proteins comparing metastatic and non-metastatic lymph nodes. Forty nine proteins were up-regulated, and sixty proteins that were down regulated in metastatic group. Bioinformatic analysis showed ECM-receptor interaction pathways to be implicated in lymph node metastasis. ELISA confirmed up-regulation of ECM proteins in metastatic lymph nodes. ECM proteins have requisite parameters to be developed as a diagnostic tool to assess status of sentinel lymph nodes to guide surgical intervention in early breast cancer.
Collapse
|
10
|
Lewis PN, Young RD, Souza RB, Quantock AJ, Meek KM. Contrast-Enhanced Tissue Processing of Fibrillin-Rich Elastic Fibres for 3D Visualization by Volume Scanning Electron Microscopy. Methods Protoc 2021; 4:mps4030056. [PMID: 34449675 PMCID: PMC8395850 DOI: 10.3390/mps4030056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/04/2021] [Accepted: 08/11/2021] [Indexed: 11/16/2022] Open
Abstract
Elastic fibres constitute an important component of the extracellular matrix and currently are the subject of intensive study in order to elucidate their assembly, function and involvement in cell-matrix interactions and disease. However, few studies to date have investigated the 3D architecture of the elastic fibre system in bulk tissue. We describe a protocol for preparation of tissue samples, including primary fixation and backscatter electron contrast-enhancement steps, through dehydration into stable resin-embedded blocks for volume electron microscopy. The use of low molecular weight tannic acid and alcoholic lead staining are critical stages in this procedure. Block preparation by ultramicrotomy and evaporative metal coating prior to microscopical examination are also described. We present images acquired from serial block face scanning electron microscopy of cornea and aorta showing target structures clearly differentiated from cells and other matrix components. The processing method imparts high contrast to fibrillin-containing elastic fibres, thus facilitating their segmentation and rendering into 3D reconstructions by image analysis software from large serial image datasets.
Collapse
Affiliation(s)
- Philip N. Lewis
- Structural Biophysics Research Group, School of Optometry & Vision Sciences, Cardiff University, Cardiff CF24 4HQ, UK; (R.D.Y.); (A.J.Q.); (K.M.M.)
- Correspondence:
| | - Robert D. Young
- Structural Biophysics Research Group, School of Optometry & Vision Sciences, Cardiff University, Cardiff CF24 4HQ, UK; (R.D.Y.); (A.J.Q.); (K.M.M.)
| | - R. B. Souza
- Department of Genetics and Evolutionary Biology, University of São Paulo, Rua de Matão 05508-090, Brazil;
| | - Andrew J. Quantock
- Structural Biophysics Research Group, School of Optometry & Vision Sciences, Cardiff University, Cardiff CF24 4HQ, UK; (R.D.Y.); (A.J.Q.); (K.M.M.)
| | - Keith M. Meek
- Structural Biophysics Research Group, School of Optometry & Vision Sciences, Cardiff University, Cardiff CF24 4HQ, UK; (R.D.Y.); (A.J.Q.); (K.M.M.)
| |
Collapse
|
11
|
Guilak F, Hayes AJ, Melrose J. Perlecan in Pericellular Mechanosensory Cell-Matrix Communication, Extracellular Matrix Stabilisation and Mechanoregulation of Load-Bearing Connective Tissues. Int J Mol Sci 2021; 22:2716. [PMID: 33800241 PMCID: PMC7962540 DOI: 10.3390/ijms22052716] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 03/04/2021] [Accepted: 03/05/2021] [Indexed: 12/14/2022] Open
Abstract
In this study, we review mechanoregulatory roles for perlecan in load-bearing connective tissues. Perlecan facilitates the co-acervation of tropoelastin and assembly of elastic microfibrils in translamellar cross-bridges which, together with fibrillin and elastin stabilise the extracellular matrix of the intervertebral disc annulus fibrosus. Pericellular perlecan interacts with collagen VI and XI to define and stabilize this matrix compartment which has a strategic position facilitating two-way cell-matrix communication between the cell and its wider extracellular matrix. Cues from the extracellular matrix are fed through this pericellular matrix back to the chondrocyte, allowing it to perceive and respond to subtle microenvironmental changes to regulate tissue homeostasis. Thus perlecan plays a key regulatory role in chondrocyte metabolism, and in chondrocyte differentiation. Perlecan acts as a transport proteoglycan carrying poorly soluble, lipid-modified proteins such as the Wnt or Hedgehog families facilitating the establishment of morphogen gradients that drive tissue morphogenesis. Cell surface perlecan on endothelial cells or osteocytes acts as a flow sensor in blood and the lacunar canalicular fluid providing feedback cues to smooth muscle cells regulating vascular tone and blood pressure, and the regulation of bone metabolism by osteocytes highlighting perlecan's multifaceted roles in load-bearing connective tissues.
Collapse
Affiliation(s)
- Farshid Guilak
- Department of Orthopaedic Surgery, Washington University, St. Louis, MO 63110, USA;
- Shriners Hospitals for Children—St. Louis, St. Louis, MO 63110, USA
| | - Anthony J. Hayes
- Bioimaging Research Hub, Cardiff School of Biosciences, Cardiff University, Cardiff, Wales CF10 3AX, UK;
| | - James Melrose
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW 2052, Australia
- Raymond Purves Laboratory, Institute of Bone and Joint Research, Kolling Institute, Northern Sydney Local Health District, Royal North Shore Hospital, St. Leonards, NSW 2065, Australia
- Sydney Medical School, Northern, University of Sydney at Royal North Shore Hospital, St. Leonards, NSW 2065, Australia
| |
Collapse
|
12
|
Yu X, Sun N, Yang X, Zhao Z, Su X, Zhang J, He Y, Lin Y, Ge J, Fan Z. Nanophthalmos-Associated MYRF Gene Mutation Causes Ciliary Zonule Defects in Mice. Invest Ophthalmol Vis Sci 2021; 62:1. [PMID: 33646289 PMCID: PMC7937999 DOI: 10.1167/iovs.62.3.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Purpose Patients with nanophthalmos who undergo intraocular surgery often present with abnormal ciliary zonules. In a previous study, we reported mutation in MYRF that is implicated in the pathogenesis of nanophthalmos. The aim of this study was to model the mutation in mice to explore the role of MYRF on zonule structure and its major molecular composition, including FBN1 and FBN2. Methods Human MYRF nanophthalmos frameshift mutation was generated in mouse using the CRISPR-Cas9 system. PCR and Sanger sequencing were used for genotype analysis of the mice model. Anterior chamber depth (ACD) was measured using hematoxylin and eosin–stained histology samples. Morphologic analysis of ciliary zonules was carried out using silver staining and immunofluorescence. Transcript and protein expression levels of MYRF, FBN1, and FBN2 in ciliary bodies were quantified using quantitative real-time PCR (qRT-PCR) and Western blot. Results A nanophthalmos frameshift mutation (c.789delC, p.N264fs) of MYRF in mice showed ocular phenotypes similar to those reported in patients with nanophthalmos. ACD was reduced in MYRF mutant mice (MYRFmut/+) compared with that in littermate control mice (MYRF+/+). In addition, the morphology of ciliary zonules showed reduced zonular fiber density and detectable structural dehiscence of zonular fibers. Furthermore, qRT-PCR analysis and Western blot showed a significant decrease in mRNA expression levels of MYRF, FBN1, and FBN2 in MYRFmut/+ mice. Conclusions Changes in the structure and major molecular composition of ciliary zonules accompanied with shallowing anterior chamber were detected in MYRFmut/+ mice. Therefore, MYRF mutant mice strain is a useful model for exploring pathogenesis of zonulopathy, which is almost elusive for basic researches due to lack of appropriate animal models.
Collapse
Affiliation(s)
- Xiaowei Yu
- State Key Laboratory of Ophthalmology, Department of Glaucoma, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Nannan Sun
- State Key Laboratory of Ophthalmology, Department of Glaucoma, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Xue Yang
- State Key Laboratory of Ophthalmology, Department of Glaucoma, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Zhenni Zhao
- State Key Laboratory of Ophthalmology, Department of Glaucoma, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Xiaoqian Su
- State Key Laboratory of Ophthalmology, Department of Glaucoma, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Jiamin Zhang
- State Key Laboratory of Ophthalmology, Department of Glaucoma, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yuqing He
- State Key Laboratory of Ophthalmology, Department of Glaucoma, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yixiu Lin
- State Key Laboratory of Ophthalmology, Department of Glaucoma, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Jian Ge
- State Key Laboratory of Ophthalmology, Department of Glaucoma, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Zhigang Fan
- State Key Laboratory of Ophthalmology, Department of Glaucoma, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, China
| |
Collapse
|
13
|
Hill JR, Eekhoff JD, Brophy RH, Lake SP. Elastic fibers in orthopedics: Form and function in tendons and ligaments, clinical implications, and future directions. J Orthop Res 2020; 38:2305-2317. [PMID: 32293749 PMCID: PMC7572591 DOI: 10.1002/jor.24695] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 03/21/2020] [Accepted: 04/11/2020] [Indexed: 02/04/2023]
Abstract
Elastic fibers are an essential component of the extracellular matrix of connective tissues. The focus of both clinical management and scientific investigation of elastic fiber disorders has centered on the cardiovascular manifestations due to their significant impact on morbidity and mortality. As such, the current understanding of the orthopedic conditions experienced by these patients is limited. The musculoskeletal implications of more subtle elastic fiber abnormalities, whether due to allelic variants or age-related tissue degeneration, are also not well understood. Recent advances have begun to uncover the effects of elastic fiber deficiency on tendon and ligament biomechanics; future research must further elucidate mechanisms governing the role of elastic fibers in these tissues. The identification of population-based genetic variations in elastic fibers will also be essential. Minoxidil administration, modulation of protein expression with micro-RNA molecules, and direct injection of recombinant elastic fiber precursors have demonstrated promise for therapeutic intervention, but further work is required prior to consideration for orthopedic clinical application. This review provides an overview of the role of elastic fibers in musculoskeletal tissue, summarizes current knowledge of the orthopedic manifestations of elastic fiber abnormalities, and identifies opportunities for future investigation and clinical application.
Collapse
Affiliation(s)
- J. Ryan Hill
- Department of Orthopaedic Surgery, Washington University in St. Louis, 425 S. Euclid Avenue, Suite 5505, St. Louis, MO 63110
| | - Jeremy D. Eekhoff
- Department of Biomedical Engineering, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130
| | - Robert H. Brophy
- Department of Orthopaedic Surgery, Washington University in St. Louis, 425 S. Euclid Avenue, Suite 5505, St. Louis, MO 63110
| | - Spencer P. Lake
- Department of Biomedical Engineering, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130,Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130
| |
Collapse
|
14
|
Eekhoff JD, Lake SP. Three-dimensional computation of fibre orientation, diameter and branching in segmented image stacks of fibrous networks. J R Soc Interface 2020; 17:20200371. [PMID: 32752994 PMCID: PMC7482563 DOI: 10.1098/rsif.2020.0371] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 07/15/2020] [Indexed: 12/27/2022] Open
Abstract
Fibre topography of the extracellular matrix governs local mechanical properties and cellular behaviour including migration and gene expression. While quantifying properties of the fibrous network provides valuable data that could be used across a breadth of biomedical disciplines, most available techniques are limited to two dimensions and, therefore, do not fully capture the architecture of three-dimensional (3D) tissue. The currently available 3D techniques have limited accuracy and applicability and many are restricted to a specific imaging modality. To address this need, we developed a novel fibre analysis algorithm capable of determining fibre orientation, fibre diameter and fibre branching on a voxel-wise basis in image stacks with distinct fibre populations. The accuracy of the technique is demonstrated on computer-generated phantom image stacks spanning a range of features and complexities, as well as on two-photon microscopy image stacks of elastic fibres in bovine tendon and dermis. Additionally, we propose a measure of axial spherical variance which can be used to define the degree of fibre alignment in a distribution of 3D orientations. This method provides a useful tool to quantify orientation distributions and variance on image stacks with distinguishable fibres or fibre-like structures.
Collapse
Affiliation(s)
- Jeremy D. Eekhoff
- Department of Biomedical Engineering, Washington University in St Louis, St Louis, MO 63110, USA
| | - Spencer P. Lake
- Department of Biomedical Engineering, Washington University in St Louis, St Louis, MO 63110, USA
- Department of Mechanical Engineering and Materials Science, Washington University in St Louis, St Louis, MO 63110, USA
- Department of Orthopaedic Surgery, Washington University in St Louis, St Louis, MO 63110, USA
| |
Collapse
|
15
|
de Souza RB, Farinha-Arcieri LE, Catroxo MHB, Martins AMCRPDF, Tedesco RC, Alonso LG, Koh IHJ, Pereira LV. Association of thoracic spine deformity and cardiovascular disease in a mouse model for Marfan syndrome. PLoS One 2019; 14:e0224581. [PMID: 31725753 PMCID: PMC6855660 DOI: 10.1371/journal.pone.0224581] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 10/16/2019] [Indexed: 12/18/2022] Open
Abstract
Aims Cardiovascular manifestations are a major cause of mortality in Marfan syndrome (MFS). Animal models that mimic the syndrome and its clinical variability are instrumental for understanding the genesis and risk factors for cardiovascular disease in MFS. This study used morphological and ultrastructural analysis to the understanding of the development of cardiovascular phenotypes of the the mgΔloxPneo model for MFS. Methods and results We studied 6-month-old female mice of the 129/Sv background, 6 wild type (WT) and 24 heterozygous animals from the mgΔloxPneo model. Descending thoracic aortic aneurysm and/or dissection (dTAAD) were identified in 75% of the MFS animals, defining two subgroups: MFS with (MFS+) and without (MFS-) dTAAD. Both subgroups showed increased fragmentation of elastic fibers, predominance of type I collagen surrounding the elastic fiber and fragmentation of interlaminar fibers when compared to WT. However, only MFS animals with spine tortuosity developed aortic aneurysm/dissection. The aorta of MFS+ animals were more tortuous compared to those of MFS- and WT mice, possibly causing perturbations of the luminal blood flow. This was evidenced by the detection of diminished aorta-blood flow in MFS+. Accordingly, only MFS+ animals presented a process of concentric cardiac hypertrophy and a significantly decreased ratio of left and right ventricle lumen area. Conclusions We show that mgΔloxPneo model mimics the vascular disease observed in MFS patients. Furthermore, the study indicates role of thoracic spine deformity in the development of aorta diseases. We suggest that degradation of support structures of the aortic wall; deficiency in the sustenance of the thoracic vertebrae; and their compression over the adjacent aorta resulting in disturbed blood flow is a triad of factors involved in the genesis of dissection/aneurysm of thoracic aorta.
Collapse
Affiliation(s)
| | | | | | | | - Roberto Carlos Tedesco
- Federal University of São Paulo, Department of Morphological and Genetics, São Paulo, SP, Brazil
| | - Luis Garcia Alonso
- Federal University of São Paulo, Department of Morphological and Genetics, São Paulo, SP, Brazil
| | - Ivan Hong Jun Koh
- Federal University of São Paulo, Department of Surgery, São Paulo, SP, Brazil
| | - Lygia V. Pereira
- University of São Paulo, Department of Genetics and Evolutionary Biology, São Paulo, SP, Brazil
- * E-mail:
| |
Collapse
|
16
|
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] [MESH Headings] [Grants] [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.
Collapse
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.
| |
Collapse
|
17
|
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.
Collapse
|
18
|
Lung Function Changes are More Common in Marfan Patients Who Need Major Thoracic Surgery. Lung 2019; 197:465-472. [PMID: 31089858 PMCID: PMC6647216 DOI: 10.1007/s00408-019-00236-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 05/02/2019] [Indexed: 11/24/2022]
Abstract
Introduction Marfan syndrome is a genetic disorder affecting the connective tissue. Changes in lung tissue might influence respiratory function; however, a detailed respiratory functional assessment according to the need for major thoracic surgery is missing. Methods Comprehensive pulmonary examinations were performed in 55 Marfan patients including respiratory symptoms, lung function (LF) testing using European Coal and Steel Community (ECSC) reference values, TLCO and quality of life measurements. Groups included patients who did not need surgery (Mf, n = 32) and those who underwent major thoracic surgery (Mfop, n = 23). Results Respiratory symptoms affected 20% of patients. Scoliosis was significantly more frequent in the Mfop group. LF demonstrated in all Marfan patients a tendency towards airway obstruction (FEV1/FVC = 0.77 ± 0.10), more prominent in Mfop patients (0.74 ± 0.08 vs. Mf: 0.80 ± 0.11; p = 0.03). Correction of LF values using a standing height modification by arm span (Hcorrected) revealed additional changes in FVC and FEV1. TLCO and quality of life did not differ between groups. Conclusions Marfan syndrome is associated with airway obstruction, especially in patients who have undergone major thoracic surgery, indicative of more severe connective tissue malfunction. The use of arm span for height correction is suitable to evaluate LF changes in this special patient group including patients with significant scoliosis.
Collapse
|
19
|
Männer J, Yelbuz TM. Functional Morphology of the Cardiac Jelly in the Tubular Heart of Vertebrate Embryos. J Cardiovasc Dev Dis 2019; 6:E12. [PMID: 30818886 PMCID: PMC6463132 DOI: 10.3390/jcdd6010012] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 02/15/2019] [Accepted: 02/21/2019] [Indexed: 12/17/2022] Open
Abstract
The early embryonic heart is a multi-layered tube consisting of (1) an outer myocardial tube; (2) an inner endocardial tube; and (3) an extracellular matrix layer interposed between the myocardium and endocardium, called "cardiac jelly" (CJ). During the past decades, research on CJ has mainly focused on its molecular and cellular biological aspects. This review focuses on the morphological and biomechanical aspects of CJ. Special attention is given to (1) the spatial distribution and fiber architecture of CJ; (2) the morphological dynamics of CJ during the cardiac cycle; and (3) the removal/remodeling of CJ during advanced heart looping stages, which leads to the formation of ventricular trabeculations and endocardial cushions. CJ acts as a hydraulic skeleton, displaying striking structural and functional similarities with the mesoglea of jellyfish. CJ not only represents a filler substance, facilitating end-systolic occlusion of the embryonic heart lumen. Its elastic components antagonize the systolic deformations of the heart wall and thereby power the refilling phase of the ventricular tube. Non-uniform spatial distribution of CJ generates non-circular cross sections of the opened endocardial tube (initially elliptic, later deltoid), which seem to be advantageous for valveless pumping. Endocardial cushions/ridges are cellularized remnants of non-removed CJ.
Collapse
Affiliation(s)
- Jörg Männer
- Group Cardio-Embryology, Institute of Anatomy and Embryology UMG, Georg-August-University Goettingen, D-37075 Goettingen, Germany.
| | - Talat Mesud Yelbuz
- Department of Cardiac Sciences, King Abdulaziz Cardiac Center, Section of Pediatric Cardiology, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh 11426, Saudi Arabia.
| |
Collapse
|
20
|
Jones W, Rodriguez J, Bassnett S. Targeted deletion of fibrillin-1 in the mouse eye results in ectopia lentis and other ocular phenotypes associated with Marfan syndrome. Dis Model Mech 2019; 12:dmm.037283. [PMID: 30642872 PMCID: PMC6361150 DOI: 10.1242/dmm.037283] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 12/11/2018] [Indexed: 01/09/2023] Open
Abstract
Fibrillin is an evolutionarily ancient protein that lends elasticity and resiliency to a variety of tissues. In humans, mutations in fibrillin-1 cause Marfan and related syndromes, conditions in which the eye is often severely affected. To gain insights into the ocular sequelae of Marfan syndrome, we targeted Fbn1 in mouse lens or non-pigmented ciliary epithelium (NPCE). Conditional knockout of Fbn1 in NPCE, but not lens, profoundly affected the ciliary zonule, the system of fibrillin-rich fibers that centers the lens in the eye. The tensile strength of the fibrillin-depleted zonule was reduced substantially, due to a shift toward production of smaller caliber fibers. By 3 months, zonular fibers invariably ruptured and mice developed ectopia lentis, a hallmark of Marfan syndrome. At later stages, untethered lenses lost their polarity and developed cataracts, and the length and volume of mutant eyes increased. This model thus captures key aspects of Marfan-related syndromes, providing insights into the role of fibrillin-1 in eye development and disease. Summary: Targeted knockout of Fbn1 in the ciliary epithelium of the mouse eye undermines the structural and biomechanical integrity of the ciliary zonule and results in an ectopia lentis phenotype.
Collapse
Affiliation(s)
- Wendell Jones
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, 660 S. Euclid Ave, Box 8096, St. Louis, MO 63117, USA
| | - Juan Rodriguez
- St Louis College of Pharmacy, Department of Basic Sciences, 4588 Parkview Place, St. Louis, MO 63110, USA
| | - Steven Bassnett
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, 660 S. Euclid Ave, Box 8096, St. Louis, MO 63117, USA
| |
Collapse
|