Academic literature on the topic 'Tropoelastin'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Tropoelastin.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Tropoelastin"
1
Saunders, N. A., and M. E. Grant. "The secretion of tropoelastin by chick-embryo artery cells." Biochemical Journal 230, no. 1 (August 15, 1985): 217–25. http://dx.doi.org/10.1042/bj2300217.
Full textAbstract:
Chymotryptic fingerprint analyses of tropoelastin a and tropoelastin b demonstrated a very close relationship between these two polypeptides synthesized in a cell-free system under the direction of chick-embryo polyribosomal mRNA. A similar study on tropoelastin polypeptides extracted in their hydroxylated and under-hydroxylated forms from artery cells incubated with [3H]valine in the absence and presence of alpha alpha'-bipyridine or 3,4-dehydroproline confirmed this close relationship and suggested that tropoelastins a and b are likely to be the products of a single gene. Pulse-chase experiments in which the synthesis and secretion of tropoelastin by artery cells were monitored demonstrated that, after a pulse with [3H]proline, the polypeptides rapidly appeared in the medium and the half-time of tropoelastin secretion was approx. 30 min. Further pulse-chase studies, in which [3H]tropoelastin contents of subcellular fractions were determined, showed that rough and smooth microsomal fractions contained maximal amounts of tropoelastin at different times. The quantity of tropoelastin in the smooth-microsomal fraction was always only a small proportion of that in the rough-microsomal fraction, suggesting rapid translocation of the polypeptides to the plasma membrane. Incubation of the cells with 0.1 mM-colchicine did not markedly alter the rate of secretion or the distribution of tropoelastin between the subcellular fractions, whereas when 1 microM-monensin was included in the incubations the polypeptides were retained in the rough microsomal fraction. The results are consistent with the proposal that tropoelastin may follow a pathway of secretion from rough endoplasmic reticulum to the plasma membrane via secretory vesicles.
2
Wise, Steven G., and Anthony S. Weiss. "Tropoelastin." International Journal of Biochemistry & Cell Biology 41, no. 3 (March 2009): 494–97. http://dx.doi.org/10.1016/j.biocel.2008.03.017.
Full text
3
Al Halawani, Aleen, Lea Abdulkhalek, Suzanne M. Mithieux, and Anthony S. Weiss. "Tropoelastin Promotes the Formation of Dense, Interconnected Endothelial Networks." Biomolecules 11, no. 9 (September 6, 2021): 1318. http://dx.doi.org/10.3390/biom11091318.
Full textAbstract:
Tropoelastin, the soluble precursor of elastin, has been used for regenerative and wound healing purposes and noted for its ability to accelerate wound repair by enhancing vascularization at the site of implantation. However, it is not clear whether these effects are directly due to the interaction of tropoelastin with endothelial cells or communicated to endothelial cells following interactions between tropoelastin and neighboring cells, such as mesenchymal stem cells (MSCs). We adapted an endothelial tube formation assay to model in vivo vascularization with the goal of exploring the stimulatory mechanism of tropoelastin. In the presence of tropoelastin, endothelial cells formed less tubes, with reduced spreading into capillary-like networks. In contrast, conditioned media from MSCs that had been cultured on tropoelastin enhanced the formation of more dense, complex, and interconnected endothelial tube networks. This pro-angiogenic effect of tropoelastin is mediated indirectly through the action of tropoelastin on co-cultured cells. We conclude that tropoelastin inhibits endothelial tube formation, and that this effect is reversed by pro-angiogenic crosstalk from tropoelastin-treated MSCs. Furthermore, we find that the known in vivo pro-angiogenic effects of tropoelastin can be modeled in vitro, highlighting the value of tropoelastin as an indirect mediator of angiogenesis.
4
Yeo, Giselle C., Anna Tarakanova, Clair Baldock, Steven G. Wise, Markus J. Buehler, and Anthony S. Weiss. "Subtle balance of tropoelastin molecular shape and flexibility regulates dynamics and hierarchical assembly." Science Advances 2, no. 2 (February 5, 2016): e1501145. http://dx.doi.org/10.1126/sciadv.1501145.
Full textAbstract:
The assembly of the tropoelastin monomer into elastin is vital for conferring elasticity on blood vessels, skin, and lungs. Tropoelastin has dual needs for flexibility and structure in self-assembly. We explore the structure-dynamics-function interplay, consider the duality of molecular order and disorder, and identify equally significant functional contributions by local and global structures. To study these organizational stratifications, we perturb a key hinge region by expressing an exon that is universally spliced out in human tropoelastins. We find a herniated nanostructure with a displaced C terminus and explain by molecular modeling that flexible helices are replaced with substantial β sheets. We see atypical higher-order cross-linking and inefficient assembly into discontinuous, thick elastic fibers. We explain this dysfunction by correlating local and global structural effects with changes in the molecule’s assembly dynamics. This work has general implications for our understanding of elastomeric proteins, which balance disordered regions with defined structural modules at multiple scales for functional assembly.
5
Pierce, R. A., W. I. Mariencheck, S. Sandefur, E. C. Crouch, and W. C. Parks. "Glucocorticoids upregulate tropoelastin expression during late stages of fetal lung development." American Journal of Physiology-Lung Cellular and Molecular Physiology 268, no. 3 (March 1, 1995): L491—L500. http://dx.doi.org/10.1152/ajplung.1995.268.3.l491.
Full textAbstract:
The production of elastin, an essential extracellular matrix protein of terminal airway interstitium, occurs mostly during early development. Because glucocorticoids influence airway maturation, we studied the effect of dexamethasone (Dex) on tropoelastin expression during fetal lung development. Timed-pregnant rats were treated with Dex (1 mg/kg daily), and fetal lungs were collected 3 days later at 17, 19, and 21 days of gestation. Dex treatment resulted in about a threefold increase in tropoelastin mRNA levels at 19 days concomitant with accelerated airway development. By in situ hybridization, Dex treatment increased the number of tropoelastin-expressing cells and the level of tropoelastin mRNA per cell. In organ culture, Dex increased lung tropoelastin expression and augmented cortisol stimulation of tropoelastin expression. In fetal pulmonary artery smooth muscle cells, 10(-8) M Dex upregulated tropoelastin mRNA expression and increased tropoelastin promoter-chloramphenicol acetyl transferase activity in transient transfections. These data indicate that pharmacologically administered glucocorticoids transcriptionally upregulate fetal lung tropoelastin expression and suggest that steroid hormones may be important regulators of elastin production in vivo.
6
Lee, Pearl, Daniel V. Bax, Marcela M. M. Bilek, and Anthony S. Weiss. "A Novel Cell Adhesion Region in Tropoelastin Mediates Attachment to Integrin αVβ5." Journal of Biological Chemistry 289, no. 3 (November 29, 2013): 1467–77. http://dx.doi.org/10.1074/jbc.m113.518381.
Full textAbstract:
Tropoelastin protein monomers assemble to form elastin. Cellular integrin αVβ3 binds RKRK at the C-terminal tail of tropoelastin. We probed cell interactions with tropoelastin by deleting the RKRK sequence to identify other cell-binding interactions within tropoelastin. We found a novel human dermal fibroblast attachment and spreading site on tropoelastin that is located centrally in the molecule. Inhibition studies demonstrated that this cell adhesion was not mediated by either elastin-binding protein or glycosaminoglycans. Cell interactions were divalent cation-dependent, indicating integrin dependence. Function-blocking monoclonal antibodies revealed that αV integrin(s) and integrin αVβ5 specifically were critical for cell adhesion to this part of tropoelastin. These data reveal a common αV integrin-binding theme for tropoelastin: αVβ3 at the C terminus and αVβ5 at the central region of tropoelastin. Each αV region contributes to fibroblast attachment and spreading, but they differ in their effects on cytoskeletal assembly.
7
Bruce, Margaret C., and Catherine E. Honaker. "Transcriptional regulation of tropoelastin expression in rat lung fibroblasts: changes with age and hyperoxia." American Journal of Physiology-Lung Cellular and Molecular Physiology 274, no. 6 (June 1, 1998): L940—L950. http://dx.doi.org/10.1152/ajplung.1998.274.6.l940.
Full textAbstract:
Elastic fibers are thought to provide structural support for secondary septa as the lung undergoes the transition from the saccular to the alveolar stage. The synthesis of the soluble precursor of elastin, tropoelastin, occurs during a finite developmental period. We have investigated the developmental regulation of tropoelastin gene transcription and mRNA expression in fetal and postnatal rat lung fibroblasts and have assessed the changes in tropoelastin gene expression caused by hyperoxic exposure during secondary septal development. With the use of an RT-PCR assay and intron-specific primers to detect heterogeneous nuclear RNA (hnRNA) and intron-spanning primers to detect mRNA in freshly isolated rat lung fibroblasts, tropoelastin gene expression was found to be upregulated late in gestation. From days 18 to 21 of gestation, there was a 4.5-fold increase in tropoelastin hnRNA ( P < 0.0001) and a 6-fold increase in mRNA ( P = 0.002). After birth, tropoelastin expression was downregulated. Signals decreased from fetal day 21 to postnatal day 2 for both tropoelastin hnRNA ( P = 0.021) and mRNA ( P = 0.043). Tropoelastin hnRNA decreased further from days 2 to 6 ( P= 0.04). Both tropoelastin hnRNA and mRNA were again upregulated during alveolarization from days 9 to 11, indicating that, once upregulated, transcription of the tropoelastin gene is not constant but varies with fetal and postnatal age. Exposure to >95% oxygen, when initiated on postnatal day 2 or 3 and continued until day 11, significantly diminished the developmental increase in tropoelastin hnRNA ( P < 0.005) and mRNA ( P < 0.05) normally seen on days 9– 11, indicating that the postnatal upregulation of tropoelastin gene expression is inhibited by hyperoxic exposure in the early postnatal period.
8
Weiss, Anthony S. "Perspectives on the Molecular and Biological Implications of Tropoelastin in Human Tissue Elasticity." Australian Journal of Chemistry 69, no. 12 (2016): 1380. http://dx.doi.org/10.1071/ch16452.
Full textAbstract:
The elasticity of a range of vertebrate and particularly human tissues depends on the dynamic and persistent protein elastin. This elasticity is diverse, and comprises skin, blood vessels, and lung, and is essential for tissue viability. Elastin is predominantly made by assembling tropoelastin, which is an asymmetric 20-nm-long protein molecule. This overview considers tropoelastin’s molecular features and biological interactions in the context of its value in tissue repair.
9
Ford, Audrey C., Hans Machula, Robert S. Kellar, and Brent A. Nelson. "Characterizing the mechanical properties of tropoelastin protein scaffolds." MRS Proceedings 1569 (2013): 45–50. http://dx.doi.org/10.1557/opl.2013.1059.
Full textAbstract:
ABSTRACTThis paper reports on mechanical characterization of electrospun tissue scaffolds formed from varying blends of collagen and human tropoelastin. The electrospun tropoelastin-based scaffolds have an open, porous structure conducive to cell attachment and have been shown to exhibit strong biocompatibility, but the mechanical character is not well known. Mechanical properties were tested for scaffolds consisting of 100% tropoelastin and 1:1 tropoelastin-collagen blends. The results showed that the materials exhibited a three order of magnitude change in the initial elastic modulus when tested dry vs. hydrated, with moduli of 21 MPa and 0.011 MPa respectively. Noncrosslinked and crosslinked tropoelastin scaffolds exhibited the same initial stiffness from 0 to 50% strain, and the noncrosslinked scaffolds exhibited no stiffness at strains >∼50%. The elastic modulus of a 1:1 tropoelastin-collagen blend was 50% higher than that of a pure tropoelastin scaffold. Finally, the 1:1 tropoelastin-collagen blend was five times stiffer from 0 to 50% strain when strained at five times the ASTM standard rate. By systematically varying protein composition and crosslinking, the results demonstrate how protein scaffolds might be manipulated as customized biomaterials, ensuring mechanical robustness and potentially improving biocompatibility through minimization of compliance mismatch with the surrounding tissue environment. Moreover, the demonstration of strain-rate dependent mechanical behavior has implications for mechanical design of tropoelastin-based tissue scaffolds.
10
Tinker, D., J. Geller, N. Romero, C. E. Cross, and R. B. Rucker. "Tropoelastin production and tropoelastin messenger RNA activity. Relationship to copper and elastin cross-linking in chick aorta." Biochemical Journal 237, no. 1 (July 1, 1986): 17–23. http://dx.doi.org/10.1042/bj2370017.
Full textAbstract:
The elastin content of the chick thoracic aorta increases 2--3-fold during the first 3 weeks post-hatching. The deposition of elastin requires the covalent cross-linking of tropoelastin by means of lysine-derived cross-links. This process is sensitive to dietary copper intake, since copper serves as cofactor for lysyl oxidase, the enzyme that catalyses the oxidative deamination of the lysine residues involved in cross-link formation. Disruption of cross-linking alters tissue concentrations of both elastin and tropoelastin and results in a net decrease in aortic elastin content. Autoregulation of tropoelastin synthesis by changes in the pool sizes of elastin or tropoelastin has been suggested as a possible mechanism for the diminished aortic elastin content. Consequently, dietary copper deficiency was induced to study the effect of impaired elastin cross-link formation on tropoelastin synthesis. Elastin in aortae from copper-deficient chicks was only two-thirds to one-half the amount measured in copper-supplemented chicks, whereas copper-deficient concentrations of tropoelastin in aorta were at least 5-fold higher than normal. In spite of these changes, however, increased amounts of tropoelastin, copper deficiency and decreased amounts of elastin did not influence the amounts of functional elastin mRNA in aorta. Likewise, the production of tropoelastin in aorta explants was the same whether the explants were taken from copper-sufficient or -deficient birds. The lower accumulation of elastin in aorta from copper-deficient chicks appeared to be due to extracellular proteolysis, rather than to a decrease in the rate of synthesis. Electrophoresis of aorta extracts, followed by immunological detection of tropoelastin-derived products, indicated degradation products in aortae from copper-deficient birds. In extracts of aortae from copper-sufficient chicks, tropoelastin was not degraded and appeared to be incorporated into elastin without further proteolytic processing.
Dissertations / Theses on the topic "Tropoelastin"
1
Tarakanova, Anna. "Molecular structure, hierarchical assembly and stimuli-responsive mechanics of tropoelastin and elastin biomaterials." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111435.
Full textAbstract:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references.
The elastin polymer, assembled from its molecular precursor tropoelastin, is the dominant component of elastic fibers, which confer elasticity and structural integrity to skin, lung, connective and vascular tissue. Historically, elastin's dynamic nature has precluded traditional approaches such as X-ray crystallography to understand its detailed features. Solving tropoelastin's atomistic structure is key to characterizing elastin's complex biological function, disease-related mechanisms associated with mutations therein, and assembly process, to replicate natural function upon impairment. From the materials perspective, elastin-based materials display tunable thermal sensitivity, presenting opportunities to mimic and control these responsive features for biomedical applications. First, we develop and validate an elastic network model of tropoelastin based on small-angle X-ray scattering to realize near-equilibrium dynamics. We identify a geometry-driven lock-and-key mechanism implicated in cell binding and multi-molecular assembly. We introduce a constitutively quiescent domain to explain the effect of local stiffness perturbation on dynamics, reconciling the contradictory needs for overall structural flexibility and the organizational requirement of specific domains towards protein self-assembly. Second, we develop an atomistic model of tropoelastin and validate it against experimental data. We introduce artificial mutations to probe the function of key molecular regions and cutis laxa-associated mutations to study disease etiology. We reveal mechanisms behind variation in structure and hierarchical assembly based on molecular geometry, secondary structure, location and exposure of hydrophobic domains, and dynamic models, correlating these with experimental results, to build a foundation for studying elastin mechanics, assembly, and disease. Third, we characterize the temperature response spectrum of elastin-like peptides to design synthetic polymers with tunable switching. We resolve the effect of peptide chemistry, chain length, and solvent environment on structural transitions, based on local molecular structure, peptide dynamics and interaction with nearest hydration shells. We build a model for a chimera silk-elastin-like protein polymer combining silk's strength with elastin's extensibility and responsive features to study temperature transition effects on molecular-scale mechanics. Simulating molecular unfolding pathways, we analyze the associated free-energy landscape with the Bell-Evans model to interpret temperature-induced phase transitions. We develop a feedback loop between simulation and experiment for predictive biomaterial design, enabling new applications in drug delivery and tissue engineering.
by Anna Tarakanova.
Ph. D.
2
Nguyen, Duy Viet Anh [Verfasser]. "Online-Marker der Gewebsentwicklung im kardiovaskulären Tissue Engineering : Evaluierung von Tropoelastin als Online-Marker der Extrazellularmatrix-Synthese im kardiovaskulären Tissue Engineering / Duy Viet Anh Nguyen." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2013. http://d-nb.info/1046977008/34.
Full text
3
Regan, David Gabriel. "NMR DIFFUSION MEASUREMENTS OF COMPARTMENTALIZED AND MULTICOMPONENT BIOLOGICAL SYSTEMS: Studies of Tropoelastin, the Self Association of N Methylacetamide, and q-Space Analysis of Real and Model Cell Suspensions." University of Sydney. School of Molecular and Microbial Biosciences, 2002. http://hdl.handle.net/2123/514.
Full textAbstract:
Molecular diffusion is an inherent feature of all fluid systems. The processes and interactions that characterize these systems are in some way dependent upon the mobility of the component molecules. Pulsed field-gradient spin-echo nuclear magnetic resonance (PGSE NMR) is a powerful tool for the study of molecular diffusion; for heterogeneous systems, such as those typically found in biology, this technique is unsurpassed in the diversity of systems that yield to its probing. The aim of the work presented in this thesis was to use an integrated NMR-based approach, in conjunction with computer modeling, for the study of molecular diffusion in compartmentalized and multicomponent biological systems. Erythrocyte suspensions provided an ideal experimental system for the study of compartmentalized diffusion in cells. Water exchanges rapidly between the intra- and extracellular regions and, as the major constituent of the cell, provides a strong and predominant proton NMR signal. In addition, the cells are known to align in the strong static magnetic field of the spectrometer. As a consequence of these two properties, the signal intensity from a suitably designed series of PGSE NMR experiments exhibits a series of maxima and minima when graphed as a function of the magnitude of the spatial wave number vector q. The apparently periodic phenomenon is mathematically analogous to optical diffraction and interference and is referred to here as diffusion-coherence. It is the characterization of this phenomenon, with the aid of computer-based models, which was the focus of a major section of the work described herein. Two quite distinct molecular systems formed the basis of the work in which I investigated diffusion in multicomponent systems. Both systems involved molecules that undergo self-association such that at equilibrium a population distribution of different oligomeric species is present. The first of these was tropoelastin, the monomeric subunit of elastin, which under certain conditions aggregates to form a coacervate. The second system was N-methylacetamide (NMA) which also undergoes extensive self-association. NMA oligomers have previously been studied as peptide analogues due to the presence in the monomer of a peptide linkage. In this work the aim was to use PGSE NMR diffusion measurements, in a manner that is in many ways analogous to analytical ultracentrifugation, to obtain estimates of hydrodynamic and thermodynamic parameters. Computer modeling was also used extensively in this section of work for the interpretation of the experimental data.
4
Broiles, JoSette Leigh Briggs. "The use of a tissue engineered media equivalent in the study of a novel smooth muscle cell phenotype." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22652.
Full textAbstract:
Thesis (Ph. D.)--Mechanical Engineering, Georgia Institute of Technology, 2008.Committee Chair: Nerem, Robert; Committee Member: Chaikof, Elliot; Committee Member: Taylor, W. Robert; Committee Member: Vito, Raymond; Committee Member: Wight, Thomas.
5
Lorion, Chloé. "Développement, caractérisation et potentiels thérapeutiques d’Elactiv’, une protéine élastique biomimétique, inspirée de la tropoélastine humaine." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10312/document.
Full textAbstract:
Les peptides élastiques (ELP, Elastin-like peptide) sont d'excellents exemples de polymères biomimétiques récemment proposés en médecine régénérative, en particulier dans le domaine de l'ingénierie tissulaire des tissus mous (peau, vaisseaux sanguins, poumons…) pour lesquels la modélisation est complexe car l'instruction correcte des cellules nécessite une élasticité fonctionnelle. L'ajustement précis de la structure primaire des ELP peut moduler voire améliorer les propriétés physico-chimiques, structurales et fonctionnelles de la protéine native. De plus, la capacité des ELP à ajuster leurs caractéristiques physico-chimiques en réponse à des stimuli externes (température, pH), les définit comme des polymères intelligents. Ces polymères bioactifs offrent ainsi une large gamme d'applications très prometteuses encore très peu explorées dans les technologies d'ingénierie tissulaire et les systèmes d'administration de médicaments. Dans ce travail de thèse, nous avons développé, caractérisé et évalué les potentiels thérapeutiques d'une protéine élastique synthétique, Elactiv', inspirée de la structure unique de la tropoélastine humaine, précurseur soluble de l'élastine. Elactiv' conserve les caractéristiques physico-chimiques (comportement thermosensible, propriétés d'autoassemblage) et les fonctions biologiques de la protéine native (prolifération, différenciation et survie des fibroblastes dermiques et kératinocytes humains, sensibilité à la dégradation enzymatique). De plus, Elactiv' possède la particularité in vitro de s'incorporer dans les fibres élastiques néo-synthétisées par des fibroblastes dermiques sains, et d'induire la synthèse de tropoélastine fibrillaire par des fibroblastes pathologiques, syndrome de Williams-Beuren, qui ne synthétisent pas ou très peu de fibres élastiques. Un hydrogel formé exclusivement d'Elactiv' a permis d'accéder aux propriétés mécaniques de l'ensemble et de vérifier sa biocompatibilité in vitro et son innocuité et sa résorption in vivo. Enfin, l'association de la protéine Elactiv' aux dendrigrafts de poly(L-lysine), polymères synthétiques hautement fonctionnalisables, a permis de faire évoluer l'architecture de l'hydrogel vers un biomatériau hybride dans le but d'augmenter ses propriétés mécaniques et biologiques. Ainsi, les potentiels biomimétiques et thérapeutiques de la protéine Elactiv' en font un candidat prometteur pour la régénération des tissus mousElastin-like peptides are excellent examples of biomimetic polymers recently proposed in regenerative medicine, particularly for soft tissue engineering (skin, blood vessels, lung ...) for which modeling is a complex task requiring functional elasticity to insctruct cells properelly. Fine-tuning of ELP’s primary structure can modulate or improve physicochemical, structural and functional properties of the native protein. In addition, the adjustment of ELP physicochemical characteristics through external stimuli (temperature, pH) defined them as intelligent polymers. These bioactive polymers thus provide a wide range of very promising applications in tissue engineering and drug delivery, although this has been under-explored until then. In this thesis, we have developed, characterized and evaluated therapeutic potentials of Elactiv', a synthetic elastic protein inspired by the unique structure of the human tropoelastin, the soluble precursor of elastin. Elactiv’ retains physicochemical characteristics (thermoresponsive behavior, self-assembly properties) and biological functions of the native protein (proliferation, differentiation and survival of human keratinocytes and dermal fibroblasts, susceptibility to enzymatic degradation). Besides, Elactiv’ is able to incorporate into neosynthesized elastic fibers by healthy dermal fibroblasts, and to induce fibrillar tropoelastin synthesis by pathological fibroblasts, Williams-Beuren syndrome, which do not synthesize or very few elastic fibres. A hydrogel formed exclusively of Elactiv’ allowed to access to mechanical properties of the scaffold and to verify its biocompatibility in vitro and its safety and resorption in vivo. Finally, the association of Elactiv' protein to poly(L-lysine) dendrigrafts, highly functionalizable synthetic polymers, enabled to evolve the hydrogel's architecture to a hybrid biomaterial in order to increase its mechanical and biological properties for skin tissue engineering. Taken together, biomimetic and therapeutic potentials of Elactiv' protein make it a promising candidate for soft tissue regeneration
6
Debelle, Laurent. "Etudes biophysiques des structures et modifications conformationnelles des tropoelastines et elastines bovines et humaines." Reims, 1995. http://www.theses.fr/1995REIMS001.
Full textAbstract:
Ce travail expose l'analyse et la quantification des structures secondaires de la tropoelastine et de l'elastine, son polymere. La prediction theorique des structures secondaires de la tropoelastine bovine et humaine montre que les monomeres de l'elastine possedent des domaines de pontages en helices alpha, alors que les regions responsables de l'elasticite, sont surtout en structures plissees. De plus, elles soulignent la possibilite d'un equilibre thermodynamique, arbitre par l'eau de structure, entre les conformations predites dans ces regions elastiques. L'analyse conjointe des spectres de dichroisme circulaire et d'absorption infrarouge a transformee de fourier de la tropoelastine bovine, ainsi que les donnees predictives affinees par l'experience, suggerent fortement un repliement tridimensionnel de type tout beta pour la tropoelastine isolee. L'analyse quantitative des spectres de diffusion raman a transformee de fourier avec excitation dans le proche infrarouge, d'absorption infrarouge a transformee de fourier et de dichroisme circulaire des elastines et kappa-elastines bovines purifiees par deux methodes (sequentielle et naoh) montre que le modele propose pour la tropoelastine isolee peut encore etre applique au polymere. L'elastomere possede donc une architecture de type goutte liquide. Dans ce contexte, un modele triphasique (proteine eau de structure eau solvant) est propose pour expliquer les relations structure elasticite de l'elastine hydratee. Cette etude sur le materiel bovin montre egalement que l'elastine est tres sensible a sa methode d'extraction. Finalement, l'etude par spectroscopies optiques des echantillons humains montre que les resultats obtenus pour le materiel bovin sont encore valables et que l'elastine semble posseder la meme structure globale quelque soit l'organe d'ou elle provient
7
Chung, Martin. "Comparative analysis of tropoelastin structure and sequence in vertebrates." 2006. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=450292&T=F.
Full text
8
Tzu-TingChen and 陳姿庭. "Oxygen plasma treatment combining tropoelastin coating to modify zirconia implant." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/7f377s.
Full text
9
Wendt, Urte Kristina [Verfasser]. "Expression von Tropoelastin und Lysinoxidase in Pflanzen / von Urte Kristina Wendt." 2002. http://d-nb.info/963919695/34.
Full text
10
Oliveira, Cátia Sofia Dias. "Development of biofunctionalized tubular scaffolds for vascular tissue engineering applications." Master's thesis, 2019. http://hdl.handle.net/1822/74942.
Full textAbstract:
Dissertação de mestrado integrado em Engenharia Biomédica (área de especialização em Biomateriais, Reabilitação e Biomecânica)One of the major problems related to small-diameter blood vessels replacement is the lack of vascular grafts with suitable mechanical and biological properties. Although there are synthetic vascular grafts in clinical use, these substitutes present thrombogenic behaviour and are too stiff compared to native vessels. Rapid endothelialization and matched mechanical properties are important functional requirements that vascular grafts should accomplish. Herein, an electrospun tubular fibrous (eTF) scaffold was fabricated and functionalized to immobilize tropoelastin at the luminal surface, providing a biomimetic environment to enhance endothelialization. The morphology was assessed by scanning electron microscopy, the effectiveness of surface functionalization by NH2 groups quantification and surface charge measurements, and the mechanical properties by uniaxial tensile tests. Tropoelastin was immobilized at 20 μg/mL by its -NH2 functional groups on activated scaffolds, as well as by its -COOH functional groups on aminolysed scaffolds, in an attempt to expose different conformations of tropoelastin for cell binding. The amount of immobilized tropoelastin on both substrates was quantified by microBCA assay. These constructs were cultured with a cell line of human umbilical vein endothelial cells (HUVECs) for 7 days, to study the endothelialization of eTF scaffolds by evaluating their metabolic activity, proliferation, total protein synthesis, VEGF secretion, as well as cell morphology and phenotype maintenance. Our experimental characterization demonstrated that the eTF scaffolds have a thickness of 240.85 ± 46.91 μm and their luminal surface was 33.55 % porous mix of micro to submicro fibers diameters, pore sizes less than 23 μm and pore areas up to 70 μm2. The eTF scaffolds were successfully functionalized by the insertion of 0.5 ± 0.04 nmol/mg of NH2 groups at their surface and confirmed by the differences observed in surface charge. Untreated, activated and aminolysed scaffolds supported higher stresses and strains in axial direction rather than in radial direction. These values are compatible to those of native blood vessels. The exposure of tropoelastin -COOH groups promoted endothelial cells metabolic activity and growth, whereas when exposed its -NH2 groups a significant influence on protein synthesis was observed. Additionally, eTF scaffolds promoted phenotype maintenance and endothelial cell coverage just after 7 days of culture. Altogether, the results confirm that biofunctional eTF scaffolds are suitable for vascular application since they presented adequate mechanical properties and a rapid endothelialization.
Um dos maiores problemas associados à substituição de vasos sanguíneos de pequeno diâmetro é a insuficiência de enxertos vasculares com propriedades mecânicas e biológicas adequadas. Embora existam enxertos vasculares sintéticos na prática clínica, estes substitutos apresentam trombogenicidade e são demasiado rígidos comparativamente aos vasos sanguíneos nativos. Uma rápida endotelização e propriedades mecânicas semelhantes aos vasos sanguíneos humanos são requisitos essenciais que um excerto vascular deve possuir. Neste trabalho, estruturas tubulares fibrosas foram produzidas por electrospinning (eTF scaffolds) e funcionalizadas para imobilizar tropoelastina na superfície interna, proporcionando um ambiente biomimético para promover a endotelização. A morfologia foi analisada por microscopia eletrónica de varrimento (SEM), a eficiência da funcionalização da superfície pela quantificação dos grupos amina (-NH2) e pela carga de superfície, e as propriedades mecânicas foram analisadas por testes uniaxiais à tração. A tropoelastina foi imobilizada a uma concentração de 20 μg/mL através dos seus grupos -NH2 nos eTF scaffolds activados, bem como pelos seus grupos carboxílicos (-COOH) nos scaffolds aminolisados, de forma a expor diferentes conformações para a ligação com as células. A quantidade de tropoelastina imobilizada em ambos os substratos foi quantificada através do método microBCA. Por último, os eTF scaffolds foram semeados com uma linha celular de células endoteliais da veia umbilical humana durante 7 dias para estudar a endotelização. Desta forma, a atividade metabólica, a proliferação celular, a síntese proteica e de VEGF, bem como a morfologia celular e a manutenção do fenótipo dos eTF scaffolds foram investigadas. Os resultados experimentais demonstraram que os eTF scaffolds possuem uma espessura de 240.85 ± 46.91 μm e uma superfície interna 33.55% porosa com diâmetros de fibras na ordem do micro ao submicro, tamanhos de poros inferiores a 23 μm e áreas de poros até 70 μm2. Os eTF scaffolds foram efetivamente funcionalizados através da inserção de 0.5 ± 0.04 nmol de grupos NH2 na superfície e pelas diferenças observadas na carga de superfície. Os eTF scaffolds não tratados, activados e aminolisados suportaram tensões e elongamentos mais elevados na direção axial do que na radial. Estes resultados obtidos são compatíveis com os valores reportados para os vasos sanguíneos nativos. A exposição dos grupos -COOH da tropoelastina induziu um aumento da atividade metabólica e crescimento das células endoteliais. Quando expostos os grupos -NH2, uma influência significativa na síntese proteica foi observada. Além disso, os eTF scaffolds promoveram a manutenção do fenótipo e a formação de uma monocamada de células endoteliais na superfície após 7 dias de cultura. De um modo geral, estes resultados confirmam que estes eTF scaffolds biofuncionais são adequados para aplicação vascular, uma vez que apresentam propriedades mecânicas adequadas e uma rápida endotelização.
Books on the topic "Tropoelastin"
1
Yang, Guocheng. An in situ atomic force microscopy (AFM) investigation of tropoelastin-like peptide assembly at ordered interfaces. Ottawa: National Library of Canada, 2002.
Find full textBook chapters on the topic "Tropoelastin"
1
Debelle, L., C. Thirion, and A. J. P. Alix. "Spectroscopic Analysis of the Conformation of Bovine Tropoelastin. Comparison with Predictive Results." In Fifth International Conference on the Spectroscopy of Biological Molecules, 125–26. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-1934-4_44.
Full text
2
Hinek, Aleksander. "The 67 kDa Spliced Variant of β-Galactosidase Serves as a Reusable Protective Chaperone for Tropoelastin." In Novartis Foundation Symposia, 185–98. Chichester, UK: John Wiley & Sons, Ltd., 2007. http://dx.doi.org/10.1002/9780470514771.ch10.
Full text
3
Wise, Steven G., Suzanne M. Mithieux, and Anthony S. Weiss. "Engineered Tropoelastin and Elastin-Based Biomaterials." In Advances in Protein Chemistry and Structural Biology, 1–24. Elsevier, 2009. http://dx.doi.org/10.1016/s1876-1623(08)78001-5.
Full text
4
Rodriguez-Pascual, Fernando. "The Evolutionary Origin of Elastin: Is Fibrillin the Lost Ancestor?" In Extracellular Matrix - Developments and Therapeutics [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.95411.
Full textAbstract:
Elastin is the extracellular matrix protein providing large arteries, lung parenchyma and skin with the properties of extensibility and elastic recoil. Within these tissues, elastin is found as a polymer formed by tropoelastin monomers assembled and cross-linked. In addition to specific protein regions supporting the covalent cross-links, tropoelastin is featured by the presence of highly repetitive sequences rich in proline and glycine making up the so-called hydrophobic domains. These protein segments promote structural flexibility and disordered protein properties, a fundamental aspect to explain its elastomeric behavior. Unlike other matrix proteins such as collagens or laminins, elastin emerged relatively late in evolution, appearing at the divergence of jawed and jawless fishes, therefore present in all species from sharks to humans, but absent in lampreys and other lower chordates and invertebrates. In spite of an intense interrogation of the key aspects in the evolution of elastin, its origin remains still elusive and an ancestral protein that could give rise to a primordial elastin is not known. In this chapter, I review the main molecular features of tropoelastin and the available knowledge on its evolutionary history as well as establish hypotheses for its origin. Considering the remarkable similarities between the hydrophobic domains of the first recognizable elastin gene from the elasmobranch Callorhinchus milii with certain fibrillin regions from related fish species, I raise the possibility that fibrillins might have provided protein domains to an ancestral elastin that thereafter underwent significant evolutionary changes to give the elastin forms found today.
Conference papers on the topic "Tropoelastin"
1
Akhtar, K., RA Pierce, RP Mecham, and TL Adair-Kirk. "Oxidative and Nitrosative Modifications of Tropoelastin Prevent Elastic Fiber Assembly." In American Thoracic Society 2009 International Conference, May 15-20, 2009 • San Diego, California. American Thoracic Society, 2009. http://dx.doi.org/10.1164/ajrccm-conference.2009.179.1_meetingabstracts.a4164.
Full text
2
Henninger, Heath B., Clayton J. Underwood, Steven J. Romney, Grant L. Davis, and Jeffrey A. Weiss. "Elastin Contributes to the Tensile Response of Medial Collateral Ligament." In ASME 2013 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/sbc2013-14075.
Full textAbstract:
Elastin provides a restorative force after deformation, stretching and recoiling through both entropic and hydrophobic mechanisms.[1, 2] Selective degradation with elastase cleaves tropoelastin, creating a fragmented network with segments that vary in size and number of crosslinks.[3] Fragments may contribute to the tissue response, so degradation level may incrementally affect the mechanics of the tissue.
3
Le, Victoria, Hiromi Yanagisawa, and Jessica Wagenseil. "Characterization of Cardiac Function and Arterial Mechanics During Early Postnatal Development in Fibulin-5 Null Mice." In ASME 2013 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/sbc2013-14282.
Full textAbstract:
Fibulin-5 is an extracellular matrix protein that interacts with other proteins during a complex process that results in elastic fiber formation from the elastin precursor, tropoelastin [1]. Elastic fibers are an important component of tissues requiring elasticity, including large arteries, lungs and skin. In mice lacking fibulin-5 ( Fbln5−/−), these tissues contain disorganized elastic fibers and exhibit decreased elasticity [2]. The phenotype of Fbln5−/− mice is similar to that of humans with cutis laxa, a connective tissue disorder characterized by loose skin and narrow arteries with reduced compliance.
4
Espinosa, Gabriela, Lisa Bennett, William Gardner, and Jessica Wagenseil. "The Effects of Extracellular Matrix Protein Insufficiency and Treatment on the Stiffness of Arterial Smooth Muscle Cells." In ASME 2013 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/sbc2013-14131.
Full textAbstract:
Increased arterial stiffness is directly correlated with hypertension and cardiovascular disease. Stiffness of the conducting arteries is largely determined by the extracellular matrix (ECM) proteins in the wall, such as collagen and elastin, produced by the smooth muscle cells (SMCs) found in the medial layer. Elastin is deposited as soluble tropoelastin and is later crosslinked into elastin fibers. Newborn mice lacking the elastin protein ( Eln−/−) have increased arterial wall stiffness and SMCs with altered proliferation, migration and morphology [1]. Vessel elasticity is also mediated by other ECM proteins, such as fibulin-4. Elastic tissue, such as lung, skin, and arteries, from fibulin-4 deficient ( Fbln4−/−) mice show no decrease in elastin content, but have reduced elasticity due to disrupted elastin fibers [2]. Arteries from both elastin and fibulin-4 deficient mice have been previously studied, but the mechanical properties of their SMCs have not been investigated. Recent experiments comparing arterial SMCs from old and young animals suggest that mechanical properties of the SMCs themselves may contribute to changes in wall stiffness [3]. Hence, we investigated the stiffness of isolated arterial SMCs from elastin and fibulin-4 deficient mice using atomic force microscopy (AFM). In addition, we studied the effects of two elastin treatments on the mechanical properties of SMCs from Eln+/+ and Eln−/− mice. Differences between the treatments may elucidate the importance of soluble versus crosslinked elastin on single cell stiffness.