1
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Degendorfer G, Chuang CY, Mariotti M, Hammer A, Hoefler G, Hägglund P, Malle E, Wise SG, Davies MJ. Exposure of tropoelastin to peroxynitrous acid gives high yields of nitrated tyrosine residues, di-tyrosine cross-links and altered protein structure and function. Free Radic Biol Med 2018; 115:219-231. [PMID: 29191462 DOI: 10.1016/j.freeradbiomed.2017.11.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 11/06/2017] [Accepted: 11/24/2017] [Indexed: 12/18/2022]
Abstract
Elastin is an abundant extracellular matrix protein in elastic tissues, including the lungs, skin and arteries, and comprises 30-57% of the aorta by dry mass. The monomeric precursor, tropoelastin (TE), undergoes complex processing during elastogenesis to form mature elastic fibres. Peroxynitrous acid (ONOOH), a potent oxidising and nitrating agent, is formed in vivo from superoxide and nitric oxide radicals. Considerable evidence supports ONOOH formation in the inflamed artery wall, and a role for this species in the development of human atherosclerotic lesions, with ONOOH-damaged extracellular matrix implicated in lesion rupture. We demonstrate that TE is highly sensitive to ONOOH, with this resulting in extensive dimerization, fragmentation and nitration of Tyr residues to give 3-nitrotyrosine (3-nitroTyr). This occurs with equimolar or greater levels of oxidant and increases in a dose-dependent manner. Quantification of Tyr loss and 3-nitroTyr formation indicates extensive Tyr modification with up to two modified Tyr per protein molecule, and up to 8% conversion of initial ONOOH to 3-nitroTyr. These effects were modulated by bicarbonate, an alternative target for ONOOH. Inter- and intra-protein di-tyrosine cross-links have been characterized by mass spectrometry. Examination of human atherosclerotic lesions shows colocalization of 3-nitroTyr with elastin epitopes, consistent with TE or elastin modification in vivo, and also an association of 3-nitroTyr containing proteins and elastin with lipid deposits. These data suggest that exposure of TE to ONOOH gives marked chemical and structural changes to TE and altered matrix assembly, and that such damage accumulates in human arterial tissue during the development of atherosclerosis.
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Affiliation(s)
| | - Christine Y Chuang
- Dept. of Biomedical Sciences, Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Michele Mariotti
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Astrid Hammer
- Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - Gerald Hoefler
- Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Per Hägglund
- Dept. of Biomedical Sciences, Panum Institute, University of Copenhagen, Copenhagen, Denmark; Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Ernst Malle
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Steven G Wise
- The Heart Research Institute, Sydney, Australia; Faculty of Medicine, University of Sydney, Sydney, Australia
| | - Michael J Davies
- The Heart Research Institute, Sydney, Australia; Dept. of Biomedical Sciences, Panum Institute, University of Copenhagen, Copenhagen, Denmark; Faculty of Medicine, University of Sydney, Sydney, Australia.
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2
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Wise SG, Liu H, Kondyurin A, Byrom MJ, Bannon PG, Edwards GA, Weiss AS, Bao S, Bilek MM. Plasma Ion Activated Expanded Polytetrafluoroethylene Vascular Grafts with a Covalently Immobilized Recombinant Human Tropoelastin Coating Reducing Neointimal Hyperplasia. ACS Biomater Sci Eng 2016; 2:1286-1297. [DOI: 10.1021/acsbiomaterials.6b00208] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Steven G. Wise
- The Heart Research Institute, 7 Eliza Street, Newtown, Sydney, New South Wales 2042, Australia
- Sydney
Medical School, University of Sydney, Edward Ford Building (A27), Fisher
Road, Sydney, New South Wales 2006, Australia
- School
of Molecular Bioscience, University of Sydney, Biochemistry Building (G08), Butlin
Avenue, Sydney, New South
Wales 2006, Australia
| | - Hongjuan Liu
- Department
of Pathology, University of Sydney, Blackburn Building (D06), Blackburn Circuit, Sydney, New South Wales 2006, Australia
| | - Alexey Kondyurin
- School
of Physics (A28), University of Sydney, Physics Road, Sydney, New South Wales 2006, Australia
| | - Michael J. Byrom
- The Heart Research Institute, 7 Eliza Street, Newtown, Sydney, New South Wales 2042, Australia
- The Baird Institute, Suite 305, 100 Carillon Avenue, Newtown, Sydney, New South Wales 2042, Australia
| | - Paul G. Bannon
- Sydney
Medical School, University of Sydney, Edward Ford Building (A27), Fisher
Road, Sydney, New South Wales 2006, Australia
- The Baird Institute, Suite 305, 100 Carillon Avenue, Newtown, Sydney, New South Wales 2042, Australia
| | - Glenn A. Edwards
- School
of Veterinary Science, University of Melbourne, 757 Swanston Street, Parkville, Victoria 3030, Australia
| | - Anthony S. Weiss
- School
of Molecular Bioscience, University of Sydney, Biochemistry Building (G08), Butlin
Avenue, Sydney, New South
Wales 2006, Australia
- Bosch
Institute, University of Sydney, Anderson Stuart Building (F13), Fisher Road, Sydney, New
South Wales 2006, Australia
- Charles
Perkins Centre (D17), University of Sydney, John Hopkins Drive, Sydney, New South Wales 2006, Australia
| | - Shisan Bao
- Department
of Pathology, University of Sydney, Blackburn Building (D06), Blackburn Circuit, Sydney, New South Wales 2006, Australia
| | - Marcela M. Bilek
- School
of Physics (A28), University of Sydney, Physics Road, Sydney, New South Wales 2006, Australia
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3
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Yeo GC, Santos M, Kondyurin A, Liskova J, Weiss AS, Bilek MMM. Plasma-Activated Tropoelastin Functionalization of Zirconium for Improved Bone Cell Response. ACS Biomater Sci Eng 2016; 2:662-676. [PMID: 33465866 DOI: 10.1021/acsbiomaterials.6b00049] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The mechanical strength, durability, corrosion resistance, and biocompatibility of metal alloys based on zirconium (Zr) and titanium (Ti) make them desirable materials for orthopedic implants. However, as bioinert metals, they do not actively promote bone formation and integration. Here we report a plasma coating process for improving integration of such metal implants with local bone tissue. The coating is a stable carbon-based plasma polymer layer that increased surface wettability by 28%, improved surface elasticity to the range exhibited by natural bone, and additionally covalently bound the extracellular matrix protein, tropoelastin, in an active conformation. The thus biofunctionalized material was significantly more resistant to medical-grade sterilization by steam, autoclaving or gamma-ray irradiation, retaining >60% of the adhered tropoelastin molecules and preserving full bioactivity. The interface of the coating and metal was robust so as to resist delamination during surgical insertion and in vivo deployment, and the plasma process employed was utilized to also coat the complex 3D geometries typical of orthopedic implants. Osteoblast-like osteosarcoma cells cultured on the biofunctionalized Zr surface exhibited a significant 30% increase in adhesion and up to 70% improvement in proliferation. Cells on these materials also showed significant early stage up-regulation of bone marker expression (alkaline phosphatase, 1.8 fold; osteocalcin, 1.4 fold), and sustained up-regulation of these genes (alkaline phosphatase, 1.3 fold; osteocalcin, 1.2 fold) in osteogenic conditions. In addition, alkaline phosphatase production significantly increased (2-fold) on the functionalized surfaces, whereas bone mineral deposition increased by 30% above background levels compared to bare Zr. These findings have the potential to be readily translated to the development of improved Zr and Ti-based implants for accelerated bone repair.
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Affiliation(s)
| | - Miguel Santos
- The Heart Research Institute, 7 Eliza Street, Newtown, New South Wales 2050, Australia
| | | | - Jana Liskova
- Institute of Physiology, Academy of Sciences of the Czech Republic, Národní 1009/3, Prague 14220, Czech Republic
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Pang JH, Farhatnia Y, Godarzi F, Tan A, Rajadas J, Cousins BG, Seifalian AM. In situ Endothelialization: Bioengineering Considerations to Translation. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2015; 11:6248-64. [PMID: 26460851 DOI: 10.1002/smll.201402579] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 06/14/2015] [Indexed: 05/10/2023]
Abstract
Improving patency rates of current cardiovascular implants remains a major challenge. It is widely accepted that regeneration of a healthy endothelium layer on biomaterials could yield the perfect blood-contacting surface. Earlier efforts in pre-seeding endothelial cells in vitro demonstrated success in enhancing patency, but translation to the clinic is largely hampered due to its impracticality. In situ endothelialization, which aims to create biomaterial surfaces capable of self-endothelializing upon implantation, appears to be an extremely promising solution, particularly with the utilization of endothelial progenitor cells (EPCs). Nevertheless, controlling cell behavior in situ using immobilized biomolecules or physical patterning can be complex, thus warranting careful consideration. This review aims to provide valuable insight into the rationale and recent developments in biomaterial strategies to enhance in situ endothelialization. In particular, a discussion on the important bio-/nanoengineering considerations and lessons learnt from clinical trials are presented to aid the future translation of this exciting paradigm.
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Affiliation(s)
- Jun Hon Pang
- Centre for Nanotechnology & Regenerative Medicine, Division of Surgery & Interventional Science, University College London (UCL), London, UK
| | - Yasmin Farhatnia
- Centre for Nanotechnology & Regenerative Medicine, Division of Surgery & Interventional Science, University College London (UCL), London, UK
| | - Fatemeh Godarzi
- Centre for Nanotechnology & Regenerative Medicine, Division of Surgery & Interventional Science, University College London (UCL), London, UK
| | - Aaron Tan
- Centre for Nanotechnology & Regenerative Medicine, Division of Surgery & Interventional Science, University College London (UCL), London, UK
- UCL Medical School, University College London (UCL), London, UK
- Biomaterials & Advanced Drug Delivery Laboratory, Stanford School of Medicine, Stanford University, Stanford, California, USA
| | - Jayakumar Rajadas
- Biomaterials & Advanced Drug Delivery Laboratory, Stanford School of Medicine, Stanford University, Stanford, California, USA
| | - Brian G Cousins
- Centre for Nanotechnology & Regenerative Medicine, Division of Surgery & Interventional Science, University College London (UCL), London, UK
| | - Alexander M Seifalian
- Centre for Nanotechnology & Regenerative Medicine, Division of Surgery & Interventional Science, University College London (UCL), London, UK
- Royal Free Hospital, London, UK
- NanoRegMed Ltd, London, UK
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Yu Y, Wise SG, Celermajer DS, Bilek MMM, Ng MKC. Bioengineering stents with proactive biocompatibility. Interv Cardiol 2015. [DOI: 10.2217/ica.15.46] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Wakelin EA, Fathi A, Kracica M, Yeo GC, Wise SG, Weiss AS, McCulloch DG, Dehghani F, Mckenzie DR, Bilek MMM. Mechanical Properties of Plasma Immersion Ion Implanted PEEK for Bioactivation of Medical Devices. ACS APPLIED MATERIALS & INTERFACES 2015; 7:23029-23040. [PMID: 26366514 DOI: 10.1021/acsami.5b06395] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Plasma immersion ion implantation (PIII) is used to modify the surface properties of polyether ether ketone for biomedical applications. Modifications to the mechanical and chemical properties are characterized as a function of ion fluence (treatment time) to determine the suitability of the treated surfaces for biological applications. Young's modulus and elastic recovery were found to increase with respect to treatment time at the surface from 4.4 to 5.2 MPa and from 0.49 to 0.68, respectively. The mechanical properties varied continuously with depth, forming a graded layer where the mechanical properties returned to untreated values deep within the layer. The treated surface layer exhibited cracking under cyclical loads, associated with an increased modulus due to dehydrogenation and cross-linking; however, it did not show any sign of delamination, indicating that the modified layer is well integrated with the substrate, a critical factor for bioactive surface coatings. The oxygen concentration remained unchanged at the surface; however, in contrast to ion implanted polymers containing only carbon and hydrogen, the oxygen concentration within the treated layer was found to decrease. This effect is attributed to UV exposure and suggests that PIII treatments can modify the surface to far greater depths than previously reported. Protein immobilization on PIII treated surfaces was found to be independent of treatment time, indicating that the surface mechanical properties can be tuned for specific applications without affecting the protein coverage. Our findings on the mechanical properties demonstrate such treatments render PEEK well suited for use in orthopedic implantable devices.
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Affiliation(s)
- Edgar A Wakelin
- Applied and Plasma Physics, School of Physics, The University of Sydney , Sydney, New South Wales 2006, Australia
| | - Ali Fathi
- School of Chemical and Biomolecular Engineering, The University of Sydney , Sydney, New South Wales 2006, Australia
| | - Masturina Kracica
- School of Applied Sciences, RMIT University , GPO BOX 476, Melbourne, Victoria 3001, Australia
| | - Giselle C Yeo
- School of Molecular Bioscience, The University of Sydney , Sydney, New South Wales 2006, Australia
- Charles Perkins Centre, The University of Sydney , Sydney, New South Wales 2006, Australia
| | - Steven G Wise
- Applied Materials Group, Heart Research Institute, Newtown 2042 and Sydney Medical School, The University of Sydney , Sydney, New South Wales 2006, Australia
| | - Anthony S Weiss
- School of Molecular Bioscience, The University of Sydney , Sydney, New South Wales 2006, Australia
- Charles Perkins Centre, The University of Sydney , Sydney, New South Wales 2006, Australia
| | - Dougal G McCulloch
- School of Applied Sciences, RMIT University , GPO BOX 476, Melbourne, Victoria 3001, Australia
| | - Fariba Dehghani
- School of Chemical and Biomolecular Engineering, The University of Sydney , Sydney, New South Wales 2006, Australia
| | - David R Mckenzie
- Applied and Plasma Physics, School of Physics, The University of Sydney , Sydney, New South Wales 2006, Australia
| | - Marcela M M Bilek
- Applied and Plasma Physics, School of Physics, The University of Sydney , Sydney, New South Wales 2006, Australia
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Yeo GC, Baldock C, Wise SG, Weiss AS. A negatively charged residue stabilizes the tropoelastin N-terminal region for elastic fiber assembly. J Biol Chem 2014; 289:34815-26. [PMID: 25342751 PMCID: PMC4263881 DOI: 10.1074/jbc.m114.606772] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 10/21/2014] [Indexed: 01/16/2023] Open
Abstract
Tropoelastin is an extracellular matrix protein that assembles into elastic fibers that provide elasticity and strength to vertebrate tissues. Although the contributions of specific tropoelastin regions during each stage of elastogenesis are still not fully understood, studies predominantly recognize the central hinge/bridge and C-terminal foot as the major participants in tropoelastin assembly, with a number of interactions mediated by the abundant positively charged residues within these regions. However, much less is known about the importance of the rarely occurring negatively charged residues and the N-terminal coil region in tropoelastin assembly. The sole negatively charged residue in the first half of human tropoelastin is aspartate 72. In contrast, the same region comprises 17 positively charged residues. We mutated this aspartate residue to alanine and assessed the elastogenic capacity of this novel construct. We found that D72A tropoelastin has a decreased propensity for initial self-association, and it cross-links aberrantly into denser, less porous hydrogels with reduced swelling properties. Although the mutant can bind cells normally, it does not form elastic fibers with human dermal fibroblasts and forms fewer atypical fibers with human retinal pigmented epithelial cells. This impaired functionality is associated with conformational changes in the N-terminal region. Our results strongly point to the role of the Asp-72 site in stabilizing the N-terminal segment of human tropoelastin and the importance of this region in facilitating elastic fiber assembly.
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Affiliation(s)
- Giselle C Yeo
- From the School of Molecular Bioscience and Charles Perkins Centre, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Clair Baldock
- the Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Steven G Wise
- the Heart Research Institute, Sydney, New South Wales 2042, Australia, and the Sydney Medical School and
| | - Anthony S Weiss
- From the School of Molecular Bioscience and Charles Perkins Centre, University of Sydney, Sydney, New South Wales 2006, Australia, Bosch Institute, University of Sydney, Sydney, New South Wales 2006, Australia
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Immobilisation of a fibrillin-1 fragment enhances the biocompatibility of PTFE. Colloids Surf B Biointerfaces 2014; 116:544-52. [DOI: 10.1016/j.colsurfb.2014.01.042] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 01/24/2014] [Accepted: 01/24/2014] [Indexed: 11/23/2022]
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Large-scale investigation of Leishmania interaction networks with host extracellular matrix by surface plasmon resonance imaging. Infect Immun 2013; 82:594-606. [PMID: 24478075 DOI: 10.1128/iai.01146-13] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
We have set up an assay to study the interactions of live pathogens with their hosts by using protein and glycosaminoglycan arrays probed by surface plasmon resonance imaging. We have used this assay to characterize the interactions of Leishmania promastigotes with ~70 mammalian host biomolecules (extracellular proteins, glycosaminoglycans, growth factors, cell surface receptors). We have identified, in total, 27 new partners (23 proteins, 4 glycosaminoglycans) of procyclic promastigotes of six Leishmania species and 18 partners (15 proteins, 3 glycosaminoglycans) of three species of stationary-phase promastigotes for all the strains tested. The diversity of the interaction repertoires of Leishmania parasites reflects their dynamic and complex interplay with their mammalian hosts, which depends mostly on the species and strains of Leishmania. Stationary-phase Leishmania parasites target extracellular matrix proteins and glycosaminoglycans, which are highly connected in the extracellular interaction network. Heparin and heparan sulfate bind to most Leishmania strains tested, and 6-O-sulfate groups play a crucial role in these interactions. Numerous Leishmania strains bind to tropoelastin, and some strains are even able to degrade it. Several strains interact with collagen VI, which is expressed by macrophages. Most Leishmania promastigotes interact with several regulators of angiogenesis, including antiangiogenic factors (endostatin, anastellin) and proangiogenic factors (ECM-1, VEGF, and TEM8 [also known as anthrax toxin receptor 1]), which are regulated by hypoxia. Since hypoxia modulates the infection of macrophages by the parasites, these interactions might influence the infection of host cells by Leishmania.
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Hiob MA, Wise SG, Kondyurin A, Waterhouse A, Bilek MM, Ng MKC, Weiss AS. The use of plasma-activated covalent attachment of early domains of tropoelastin to enhance vascular compatibility of surfaces. Biomaterials 2013; 34:7584-91. [PMID: 23863453 DOI: 10.1016/j.biomaterials.2013.06.036] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2013] [Accepted: 06/23/2013] [Indexed: 12/13/2022]
Abstract
All current metallic vascular prostheses, including stents, exhibit suboptimal biocompatibility. Improving the re-endothelialization and reducing the thrombogenicity of these devices would substantially improve their clinical efficacy. Tropoelastin (TE), the soluble precursor of elastin, mediates favorable endothelial cell interactions while having low thrombogenicity. Here we show that constructs of TE corresponding to the first 10 ("N10") and first 18 ("N18") N-terminal domains of the molecule facilitate endothelial cell attachment and proliferation equivalent to the performance of full-length TE. This N-terminal ability contrasts with the known role of the C-terminus of TE in facilitating cell attachment, particularly of fibroblasts. When immobilized on a plasma-activated coating ("PAC"), N10 and N18 retained their bioactivity and endothelial cell interactive properties, demonstrating attachment and proliferation equivalent to full-length TE. In whole blood assays, both N10 and N18 maintained the low thrombogenicity of PAC. Furthermore, these N-terminal constructs displayed far greater resistance to protease degradation by blood serine proteases kallikrein and thrombin than did full-length TE. When immobilized onto a PAC surface, these shorter constructs form a modified metal interface to establish a platform technology for biologically compatible, implantable cardiovascular devices.
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Affiliation(s)
- Matti A Hiob
- School of Molecular Bioscience, University of Sydney, Sydney, NSW 2006, Australia
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Almine JF, Wise SG, Hiob M, Singh NK, Tiwari KK, Vali S, Abbasi T, Weiss AS. Elastin sequences trigger transient proinflammatory responses by human dermal fibroblasts. FASEB J 2013; 27:3455-65. [PMID: 23671273 DOI: 10.1096/fj.13-231787] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Following penetrating injury of the skin, a highly orchestrated and overlapping sequence of events helps to facilitate wound resolution. Inflammation is a hallmark that is initiated early, but the reciprocal relationship between cells and matrix molecules that triggers and maintains inflammation is poorly appreciated. Elastin is enriched in the deep dermis of skin. We propose that deep tissue injury encompasses elastin damage, yielding solubilized elastin that triggers inflammation. As dermal fibroblasts dominate the deep dermis, this means that a direct interaction between elastin sequences and fibroblasts would reveal a proinflammatory signature. Tropoelastin was used as a surrogate for elastin sequences. Tropoelastin triggered fibroblast expression of the metalloelastase MMP-12, which is normally expressed by macrophages. MMP-12 expression increased 1056 ± 286-fold by 6 h and persisted for 24 h. Chemokine expression was more transient, as chemokine C-X-C motif ligand 8 (CXCL8), CXCL1, and CXCL5 transcripts increased 11.8 ± 2.6-, 10.2 ± 0.4-, and 8593 ± 996-fold, respectively, by 6-12 h and then decreased. Through the use of specific inhibitors and protein truncation, we found that transduction of the tropoelastin signal was mediated by the fibroblast elastin binding protein (EBP). In silico modeling using a predictive computational fibroblast model confirmed the up-regulation, and simulations revealed PKA as a key part of the signaling circuit. We tested this prediction with 1 μM PKA inhibitor H-89 and found that 2 h of exposure correspondingly reduced expression of MMP-12 (63.9±12.3%) and all chemokine markers, consistent with the levels seen with EBP inhibition, and validated PKA as a novel node and druggable target to ameliorate the proinflammatory state. A separate trigger that utilized C-terminal RKRK of tropoelastin reduced marker expression to 65.0-76.5% and suggests the parallel involvement of integrin αVβ3. We propose that the solubilization of elastin as a result of dermal damage leads to rapid chemokine up-regulation by fibroblasts that is quenched when exposed elastin is removed by MMP-12.
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Affiliation(s)
- Jessica F Almine
- School of Molecular Bioscience, University of Sydney, NSW 2006, Australia
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Tropoelastin--a multifaceted naturally smart material. Adv Drug Deliv Rev 2013; 65:421-8. [PMID: 22784558 DOI: 10.1016/j.addr.2012.06.009] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 06/09/2012] [Accepted: 06/21/2012] [Indexed: 12/18/2022]
Abstract
Tropoelastin dominates the physical performance of human elastic tissue as it is assembled to make elastin. Tropoelastin is increasingly appreciated as a protein monomer with a defined solution shape comprising modular, bridged regions that specialize in elasticity and cell attachment, which collectively participate in macromolecular assembly. This modular, multifaceted molecule is being exploited to enhance the physical performance and biological presentation of engineered constructs to augment and repair human tissues. These tissues include skin and vasculature, and emphasize how growing knowledge of tropoelastin can be powerfully adapted to add value to pre-existing devices like stents and novel, multi-featured biological implants.
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