Journal articles on the topic 'Elastin fibers'
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1
Akiyama, Mari. "Elastic Fibers and F-Box and WD-40 Domain-Containing Protein 2 in Bovine Periosteum and Blood Vessels." Biomimetics 8, no. 1 (December 23, 2022): 7. http://dx.doi.org/10.3390/biomimetics8010007.
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Elastic fibers form vessel walls, and elastic fiber calcification causes serious vascular diseases. Elastin is a well-known elastic fiber component; however, the insoluble nature of elastic fibers renders elastic fiber component analysis difficult. A previous study investigated F-box and WD-40 domain-containing protein 2 (FBXW2) in the cambium layer of bovine periosteum and hypothesized that fiber structures of FBXW2 are coated with osteocalcin during explant culture. Here, FBXW2 was expressed around some endothelial cells but not in all microvessels of the bovine periosteum. The author hypothesized that FBXW2 is expressed only in blood vessels with elastic fibers. Immunostaining and Elastica van Gieson staining indicated that FBXW2 was expressed in the same regions as elastic fibers and elastin in the cambium layer of the periosteum. Alpha-smooth muscle actin (αSMA) was expressed in microvessels and periosteum-derived cells. Immunostaining and observation of microvessels with serial sections revealed that osteocalcin was not expressed around blood vessels at 6 and 7 weeks. However, blood vessels and periosteum connoted elastic fibers, FBXW2, and αSMA. These findings are expected to clarify the processes involved in the calcification of elastic fibers in blood vessels.
2
Schwartz, E., and R. Fleischmajer. "Association of elastin with oxytalan fibers of the dermis and with extracellular microfibrils of cultured skin fibroblasts." Journal of Histochemistry & Cytochemistry 34, no. 8 (August 1986): 1063–68. http://dx.doi.org/10.1177/34.8.3525665.
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The formation of a mature elastic fiber is thought to proceed by the deposition of elastin on pre-existing microfibrils (10-12 nm in diameter). Immunohistochemical evidence has suggested that in developing tissues such as aorta and ligamentum nuchae, small amounts of elastin are associated with microfibrils but are not detected at the light microscopic and ultrastructural levels. Dermal tissue contains a complex elastic fiber system consisting of three types of fibers--oxytalan, elaunin, and elastic--which are believed to differ in their relative contents of microfibrils and elastin. According to ultrastructural analysis, oxytalan fibers contain only microfibrils, elaunin fibers contain small quantities of amorphous elastin, and elastic fibers are predominantly elastin. Using indirect immunofluorescence techniques, we demonstrate in this study that nonamorphous elastin is associated with the oxytalan fibers. Frozen sections of normal skin were incubated with antibodies directed against human aortic alpha elastin and against microfibrillar proteins isolated from cultured calf aortic smooth muscle cells. The antibodies to the microfibrillar proteins and elastin reacted strongly with the oxytalan fibers of the upper dermis. Oxytalan fibers therefore are composed of both microfibrils and small amounts of elastin. Elastin was demonstrated extracellularly in human skin fibroblasts in vitro by indirect immunofluorescence. The extracellular association of nonamorphous elastin and microfibrils on similar fibrils was visualized by immunoelectron microscopy. Treatment of these cultures with sodium dodecyl sulfate/mercaptoethanol (SDS/ME) solubilized tropoelastin and other proteins that reacted with the antibodies to the microfibrillar proteins. It was concluded that the association of the microfibrils with nonamorphous elastin in intact dermis and cultured human skin fibroblasts may represent the initial step in elastogenesis.
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Zheng, Qian, Elaine C. Davis, James A. Richardson, Barry C. Starcher, Tiansen Li, Robert D. Gerard, and Hiromi Yanagisawa. "Molecular Analysis of Fibulin-5 Function during De Novo Synthesis of Elastic Fibers." Molecular and Cellular Biology 27, no. 3 (February 1, 2007): 1083–95. http://dx.doi.org/10.1128/mcb.01330-06.
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ABSTRACT Elastic fibers contribute to the structural support of tissues and to the regulation of cellular behavior. Mice deficient for the fibulin-5 gene (fbln5 − / −) were used to further elucidate the molecular mechanism of elastic fiber assembly. Major elastic fiber components were present in the skin of fbln5 − / − mice despite a dramatic reduction of mature elastic fibers. We found that fibulin-5 preferentially bound the monomeric form of elastin through N-terminal and C-terminal elastin-binding regions and to a preexisting matrix scaffold through calcium-binding epidermal growth factor (EGF)-like (CB-EGF) domains. We further showed that adenovirus-mediated gene transfer of fbln5 was sufficient to regenerate elastic fibers and increase elastic fiber-cell connections in vivo. A mutant fibulin-5 lacking the first 28 amino acids of the first CB-EGF domain, however, was unable to rescue elastic fiber defects. Fibulin-5 thus serves as an adaptor molecule between monomeric elastin and the matrix scaffold to aid in elastic fiber assembly. These results also support the potential use of fibulin-5 as a therapeutic agent for the treatment of elastinopathies.
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Roark, E. F., D. R. Keene, C. C. Haudenschild, S. Godyna, C. D. Little, and W. S. Argraves. "The association of human fibulin-1 with elastic fibers: an immunohistological, ultrastructural, and RNA study." Journal of Histochemistry & Cytochemistry 43, no. 4 (April 1995): 401–11. http://dx.doi.org/10.1177/43.4.7534784.
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We examined the pattern of fibulin-1 mRNA and protein expression in human tissues and cell lines. Fibulin-1 transcripts were found in RNA isolated from most tissues and a variety of cultured cells, including fibroblasts, smooth muscle cells, and several epithelial cell lines, but not endothelial cells, lymphomyloid cells, or a number of carcinoma and melanoma lines. Immunohistochemical analysis showed that fibulin-1 is an intercellular component of connective tissues, predominantly associated with matrix fibers in tissues such as the cervix, dermis, intimal and medial layers of blood vessels, heart valves, meningeal tissue of the brain, Wharton's jelly of the umbilical cord, testis, and lung. Most of the fibers that were immunoreactive with fibulin-1 antibodies also stained with antibodies to the elastic fiber proteins elastin and fibrillin, as well as with Verhoeff's elastin stain. Immunoelectron microscopic analysis of elastin fibers of skin and saphenous vein revealed that fibulin-1 was located within the amorphous core of the fibers, similar to elastin, but it was not in the fibrillin-containing, elastin-associated microfibrils. Our finding that fibulin-1 is an elastic fiber component suggests several possible new functions for fibulin-1, e.g., that it is a structural protein that contributes to the elastic properties of connective tissue fibers or that is involved with the process of fibrogenesis.
5
Fhayli, Wassim, Quentin Boëté, Nadjib Kihal, Valérie Cenizo, Pascal Sommer, Walter A. Boyle, Marie-Paule Jacob, and Gilles Faury. "Dill Extract Induces Elastic Fiber Neosynthesis and Functional Improvement in the Ascending Aorta of Aged Mice with Reversal of Age-Dependent Cardiac Hypertrophy and Involvement of Lysyl Oxidase-Like-1." Biomolecules 10, no. 2 (January 23, 2020): 173. http://dx.doi.org/10.3390/biom10020173.
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Elastic fibers (90% elastin, 10% fibrillin-rich microfibrils) are synthesized only in early life and adolescence mainly by the vascular smooth muscle cells through the cross-linking of its soluble precursor, tropoelastin. Elastic fibers endow the large elastic arteries with resilience and elasticity. Normal vascular aging is associated with arterial remodeling and stiffening, especially due to the end of production and degradation of elastic fibers, leading to altered cardiovascular function. Several pharmacological treatments stimulate the production of elastin and elastic fibers. In particular, dill extract (DE) has been demonstrated to stimulate elastin production in vitro in dermal equivalent models and in skin fibroblasts to increase lysyl oxidase–like-1 (LOXL-1) gene expression, an enzyme contributing to tropoelastin crosslinking and elastin formation. Here, we have investigated the effects of a chronic treatment (three months) of aged male mice with DE (5% or 10% v/v, in drinking water) on the structure and function of the ascending aorta. DE treatment, especially at 10%, of aged mice protected pre-existing elastic lamellae, reactivated tropoelastin and LOXL-1 expressions, induced elastic fiber neo-synthesis, and decreased the stiffness of the aging aortic wall, probably explaining the reversal of the age-related cardiac hypertrophy also observed following the treatment. DE could thus be considered as an anti-aging product for the cardiovascular system.
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Saitow, Cassandra B., Steven G. Wise, Anthony S. Weiss, John J. Castellot, and David L. Kaplan. "Elastin biology and tissue engineering with adult cells." BioMolecular Concepts 4, no. 2 (April 1, 2013): 173–85. http://dx.doi.org/10.1515/bmc-2012-0040.
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AbstractThe inability of adult cells to produce well-organized, robust elastic fibers has long been a barrier to the successful engineering of certain tissues. In this review, we focus primarily on elastin with respect to tissue-engineered vascular substitutes. To understand elastin regulation during normal development, we describe the role of various elastic fiber accessory proteins. Biochemical pathways regulating expression of the elastin gene are addressed, with particular focus on tissue-engineering research using adult-derived cells.
7
Nygaard, Rie Harboe, Scott Maynard, Peter Schjerling, Michael Kjaer, Klaus Qvortrup, Vilhelm A. Bohr, Lene J. Rasmussen, Gregor B. E. Jemec, and Michael Heidenheim. "Acquired Localized Cutis Laxa due to Increased Elastin Turnover." Case Reports in Dermatology 8, no. 1 (February 13, 2016): 42–51. http://dx.doi.org/10.1159/000443696.
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Cutis laxa is a rare disease characterized by abnormal skin wrinkling and laxity, due to decreased elastin synthesis or structural extracellular matrix defects. We have explored elastin metabolism in a case of adult onset cutis laxa localized to the upper body of a woman. For this purpose, we obtained skin biopsies from affected and unaffected skin areas of the patient and analyzed these with microscopy, polymerase chain reaction, western blotting and cell culture experiments. Skin from the affected area lacked elastin fibers in electron microscopy but had higher mRNA expression of elastin and total RNA. Levels of an apparent tropoelastin degradation product were higher in the affected area. Fibroblast cultures from the affected area were able to produce elastin and showed higher proliferation and survival after oxidative and UVB stress compared to fibroblasts from the unaffected area. In conclusion, we report a case of acquired localized cutis laxa with a lack of elastic fibers in the skin of the patient's upper body. The lack of elastic fibers in the affected skin was combined with increased mRNA expression and protein levels of elastin. These findings indicate that elastin synthesis was increased but did not lead to deposited elastic fibers in the tissue.
8
McLaughlin, Precious J., Qiuyun Chen, Masahito Horiguchi, Barry C. Starcher, J. Brett Stanton, Thomas J. Broekelmann, Alan D. Marmorstein, et al. "Targeted Disruption of Fibulin-4 Abolishes Elastogenesis and Causes Perinatal Lethality in Mice." Molecular and Cellular Biology 26, no. 5 (March 1, 2006): 1700–1709. http://dx.doi.org/10.1128/mcb.26.5.1700-1709.2006.
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ABSTRACT Elastic fibers provide tissues with elasticity which is critical to the function of arteries, lungs, skin, and other dynamic organs. Loss of elasticity is a major contributing factor in aging and diseases. However, the mechanism of elastic fiber development and assembly is poorly understood. Here, we show that lack of fibulin-4, an extracellular matrix molecule, abolishes elastogenesis. fibulin-4 −/− mice generated by gene targeting exhibited severe lung and vascular defects including emphysema, artery tortuosity, irregularity, aneurysm, rupture, and resulting hemorrhages. All the homozygous mice died perinatally. The earliest abnormality noted was a uniformly narrowing of the descending aorta in fibulin-4 −/− embryos at embryonic day 12.5 (E12.5). Aorta tortuosity and irregularity became noticeable at E15.5. Histological analysis demonstrated that fibulin-4 −/− mice do not develop intact elastic fibers but contain irregular elastin aggregates. Electron microscopy revealed that the elastin aggregates are highly unusual in that they contain evenly distributed rod-like filaments, in contrast to the amorphous appearance of normal elastic fibers. Desmosine analysis indicated that elastin cross-links in fibulin-4 −/− tissues were largely diminished. However, expression of tropoelastin or lysyl oxidase mRNA was unaffected in fibulin-4 −/− mice. In addition, fibulin-4 strongly interacts with tropoelastin and colocalizes with elastic fibers in culture. These results demonstrate that fibulin-4 plays an irreplaceable role in elastogenesis.
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Wilharm, Nils, Tony Fischer, Alexander Hayn, and Stefan G. Mayr. "Structural Breakdown of Collagen Type I Elastin Blend Polymerization." Polymers 14, no. 20 (October 20, 2022): 4434. http://dx.doi.org/10.3390/polym14204434.
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Biopolymer blends are advantageous materials with novel properties that may show performances way beyond their individual constituents. Collagen elastin hybrid gels are a new representative of such materials as they employ elastin’s thermo switching behavior in the physiological temperature regime. Although recent studies highlight the potential applications of such systems, little is known about the interaction of collagen and elastin fibers during polymerization. In fact, the final network structure is predetermined in the early and mostly arbitrary association of the fibers. We investigated type I collagen polymerized with bovine neck ligament elastin with up to 33.3 weight percent elastin and showed, by using a plate reader, zeta potential and laser scanning microscopy (LSM) experiments, that elastin fibers bind in a lateral manner to collagen fibers. Our plate reader experiments revealed an elastin concentration-dependent increase in the polymerization rate, although the rate increase was greatest at intermediate elastin concentrations. As elastin does not significantly change the structural metrics pore size, fiber thickness or 2D anisotropy of the final gel, we are confident to conclude that elastin is incorporated homogeneously into the collagen fibers.
10
Bressan, G. M., D. Daga-Gordini, A. Colombatti, I. Castellani, V. Marigo, and D. Volpin. "Emilin, a component of elastic fibers preferentially located at the elastin-microfibrils interface." Journal of Cell Biology 121, no. 1 (April 1, 1993): 201–12. http://dx.doi.org/10.1083/jcb.121.1.201.
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The fine distribution of the extracellular matrix glycoprotein emilin (previously known as glycoprotein gp115) (Bressan, G. M., I. Castellani, A. Colombatti, and D. Volpin. 1983. J. Biol. Chem. 258: 13262-13267) has been studied at the ultrastructural level with specific antibodies. In newborn chick aorta the protein was exclusively found within elastic fibers. In both post- and pre-embedding immunolabeling emilin was mainly associated with regions where elastin and microfibrils are in close contact, such as the periphery of the fibers. This localization of emilin in aorta has been confirmed by quantitative evaluation of the distribution of gold particles within elastic fibers. In other tissues, besides being associated with typical elastic fibers, staining for emilin was found in structures lacking amorphous elastin, but where the presence of tropoelastin has been demonstrated by immunoelectron microscopy. This was particularly evident in the oxitalan fibers of the corneal stroma, in the Descemet's membrane, and in the ciliary zonule. Analysis of embryonic aorta revealed the presence of emilin at early stages of elastogenesis, before the appearance of amorphous elastin. Immunofluorescence studies have shown that emilin produced by chick embryo aorta cells in culture is strictly associated with elastin and that the process of elastin deposition is severely altered by the presence of antiemilin antibodies in the culture medium. The name of the protein was derived from its localization at sites where elastin and microfibrils are in proximity (emilin, elastin microfibril interface located protein).
11
Robb, Bruce W., Hiroshi Wachi, Theresa Schaub, Robert P. Mecham, and Elaine C. Davis. "Characterization of an In Vitro Model of Elastic Fiber Assembly." Molecular Biology of the Cell 10, no. 11 (November 1999): 3595–605. http://dx.doi.org/10.1091/mbc.10.11.3595.
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Elastic fibers consist of two morphologically distinct components: elastin and 10-nm fibrillin-containing microfibrils. During development, the microfibrils form bundles that appear to act as a scaffold for the deposition, orientation, and assembly of tropoelastin monomers into an insoluble elastic fiber. Although microfibrils can assemble independent of elastin, tropoelastin monomers do not assemble without the presence of microfibrils. In the present study, immortalized ciliary body pigmented epithelial (PE) cells were investigated for their potential to serve as a cell culture model for elastic fiber assembly. Northern analysis showed that the PE cells express microfibril proteins but do not express tropoelastin. Immunofluorescence staining and electron microscopy confirmed that the microfibril proteins produced by the PE cells assemble into intact microfibrils. When the PE cells were transfected with a mammalian expression vector containing a bovine tropoelastin cDNA, the cells were found to express and secrete tropoelastin. Immunofluorescence and electron microscopic examination of the transfected PE cells showed the presence of elastic fibers in the matrix. Biochemical analysis of this matrix showed the presence of cross-links that are unique to mature insoluble elastin. Together, these results indicate that the PE cells provide a unique, stable in vitro system in which to study elastic fiber assembly.
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Joss-Moore, Lisa A., Yan Wang, Xing Yu, Michael S. Campbell, Christopher W. Callaway, Robert A. McKnight, Albert Wint, et al. "IUGR decreases elastin mRNA expression in the developing rat lung and alters elastin content and lung compliance in the mature rat lung." Physiological Genomics 43, no. 9 (May 2011): 499–505. http://dx.doi.org/10.1152/physiolgenomics.00183.2010.
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Complications of intrauterine growth restriction (IUGR) include increased pulmonary morbidities and impaired alveolar development. Normal alveolar development depends upon elastin expression and processing, as well as the formation and deposition of elastic fibers. This is true of the human and rat. In this study, we hypothesized that uteroplacental insufficiency (UPI)-induced IUGR decreases mRNA levels of elastin and genes required for elastin fiber synthesis and assembly, at birth (prealveolarization) and postnatal day 7 (midalveolarization) in the rat. We further hypothesized that this would be accompanied by reduced elastic fiber deposition and increased static compliance at postnatal day 21 (mature lung). We used a well characterized rat model of IUGR to test these hypotheses. IUGR decreases mRNA transcript levels of genes essential for elastic fiber formation, including elastin, at birth and day 7. In the day 21 lung, IUGR decreases elastic fiber deposition and increases static lung compliance. We conclude that IUGR decreases mRNA transcript levels of elastic fiber synthesis genes, before and during alveolarization leading to a reduced elastic fiber density and increased static lung compliance in the mature lung. We speculate that the mechanism by which IUGR predisposes to pulmonary disease may be via decreased lung elastic fiber deposition.
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Hurle, J. M., G. Corson, K. Daniels, R. S. Reiter, L. Y. Sakai, and M. Solursh. "Elastin exhibits a distinctive temporal and spatial pattern of distribution in the developing chick limb in association with the establishment of the cartilaginous skeleton." Journal of Cell Science 107, no. 9 (September 1, 1994): 2623–34. http://dx.doi.org/10.1242/jcs.107.9.2623.
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In this work we have analyzed the presence of elastic components in the extracellular matrices of the developing chick leg bud. The distributions of elastin and fibrillin were studied immunohistochemically in whole-mount preparations using confocal laser microscopy. The association of these constituents of the elastic matrix with other components of the extracellular matrix was also studied, using several additional antibodies. Our results reveal the transient presence of an elastin-rich scaffold of extracellular matrix fibrillar material in association with the establishment of the cartilaginous skeleton of the leg bud. The scaffold consisted of elastin-positive fibers extending from the ectodermal surface of the limb to the central cartilage-forming regions and between adjacent cartilages. Fibrillin immunolabeling was negative in this fibrillar scaffold while other components of the extracellular matrix including: tenascin, laminin and collagens type I, type III and type VI; appeared codistributed with elastin in some regions of the scaffold. Progressive changes in the spatial pattern of distribution of the elastin-positive scaffold were detected in explant cultures in which one expects a modification in the mechanical stresses of the tissues related to growth. A scaffold of elastin comparable to that found in vivo was also observed in high-density micromass cultures of isolated limb mesodermal cells. In this case the elastic fibers are observed filling the spaces located between the cartilaginous nodules. The fibers become reoriented and attach to the ectodermal basal surface when an ectodermal fragment is located at the top of the growing micromass. Our results suggest that the formation of the cartilaginous skeleton of the limb involves the segregation of the undifferentiated limb mesenchyme into chondrogenic and elastogenic cell lineages. Further, a role for the elastic fiber scaffold in coordinating the size and the spatial location of the cartilaginous skeletal elements within the limb bud is also suggested from our observations.
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Starcher, Barry, Alessandra d'Azzo, Patrick W. Keller, Gottipati K. Rao, Deepa Nadarajah, and Alexsander Hinek. "Neuraminidase-1 is required for the normal assembly of elastic fibers." American Journal of Physiology-Lung Cellular and Molecular Physiology 295, no. 4 (October 2008): L637—L647. http://dx.doi.org/10.1152/ajplung.90346.2008.
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The assembly of elastic fibers in tissues that undergo repeated cycles of extension and recoil, such as the lungs and blood vessels, is dependent on the proper interaction and alignment of tropoelastin with a microfibrillar scaffold. Here, we describe in vivo histopathological effects of neuraminidase-1 (Neu1) deficiency on elastin assembly in the lungs and aorta of mice. These mice exhibited a tight-skin phenotype very similar to the Tsk mouse. Normal septation of Neu1-null mice did not occur in neonatal mice, resulting in enlarged alveoli that were maintained in adults. The abnormal development of elastic fibers was remarkable under electron microscopy and confirmed by the overlapping distribution of elastin, fibrillin-1, fibrillin-2, and fibulin-5 (Fib-5) by the light microscopy immunostainings. Fib-5 fibers appeared diffuse and unorganized around the alveolar walls and the apex of developing secondary septal crests. Fibrillin-2 deposition was also abnormal in neonatal and adult lungs. Dispersion of myofibroblasts appeared abnormal in developing lungs of Neu1-null mice, with a random distribution of myofibroblast around the alveolar walls, rather than concentrating at sites of elastin synthesis. The elastic lamellae in the aorta of the Neu1-null mice were thinner and separated by hypertrophic smooth muscle cells that were surrounded by an excess of the sialic acid-containing moieties. The concentration of elastin, as measure by desmosine levels, was significantly reduced in the aorta of Neu1-null mice. Message levels for tropoelastin and Fib-5 were normal, suggesting the elastic fiber defects in Neu1-null mice result from impaired extracellular assembly.
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Hirobe, Tomohisa, and Hisao Enami. "Reduced Elastin Fibers and Melanocyte Loss in Vitiliginous Skin Are Restored after Repigmentation by Phototherapy and/or Autologous Minigraft Transplantation." International Journal of Molecular Sciences 23, no. 23 (December 6, 2022): 15361. http://dx.doi.org/10.3390/ijms232315361.
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Vitiligo is a hypopigmentation disease characterized by melanocyte death in the human epidermis. However, the mechanism of vitiligo development and repigmentation is largely unknown. Dermal fiber components might play an important role in vitiligo development and repigmentation. Indeed, our preliminary study demonstrated that elastin fibers were decreased in vitiliginous skin, suggesting that the elastin fiber is one of the factors involved in vitiligo development and repigmentation. To confirm our hypothesis, we investigated whether elastin fibers can be restored after treatment using phototherapy and/or autologous skin transplantation. Punch biopsies from 14 patients of stable nonsegmental vitiligo vulgaris were collected from nonlesional, lesional, and repigmented skin, and processed to dopa and combined dopa–premelanin reactions. Melanocytes positive to the dopa reaction and melanoblasts/melanocytes positive to the combined dopa–premelanin reaction were surveyed. Moreover, elastin fibers were detected by Victoria blue staining. Numerous melanocytes and melanoblasts were observed in the epidermis of repigmented skin after the treatment. Moreover, in the dermis of repigmented skin, elastin fibers were completely recovered or even upregulated. These results suggest that melanocyte loss in the vitiliginous skin, as well as melanocyte differentiation in repigmented skin, may be at least in part regulated by elastin fibers in the dermis.
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Cocciolone, Austin J., Jie Z. Hawes, Marius C. Staiculescu, Elizabeth O. Johnson, Monzur Murshed, and Jessica E. Wagenseil. "Elastin, arterial mechanics, and cardiovascular disease." American Journal of Physiology-Heart and Circulatory Physiology 315, no. 2 (August 1, 2018): H189—H205. http://dx.doi.org/10.1152/ajpheart.00087.2018.
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Large, elastic arteries are composed of cells and a specialized extracellular matrix that provides reversible elasticity and strength. Elastin is the matrix protein responsible for this reversible elasticity that reduces the workload on the heart and dampens pulsatile flow in distal arteries. Here, we summarize the elastin protein biochemistry, self-association behavior, cross-linking process, and multistep elastic fiber assembly that provide large arteries with their unique mechanical properties. We present measures of passive arterial mechanics that depend on elastic fiber amounts and integrity such as the Windkessel effect, structural and material stiffness, and energy storage. We discuss supravalvular aortic stenosis and autosomal dominant cutis laxa-1, which are genetic disorders caused by mutations in the elastin gene. We present mouse models of supravalvular aortic stenosis, autosomal dominant cutis laxa-1, and graded elastin amounts that have been invaluable for understanding the role of elastin in arterial mechanics and cardiovascular disease. We summarize acquired diseases associated with elastic fiber defects, including hypertension and arterial stiffness, diabetes, obesity, atherosclerosis, calcification, and aneurysms and dissections. We mention animal models that have helped delineate the role of elastic fiber defects in these acquired diseases. We briefly summarize challenges and recent advances in generating functional elastic fibers in tissue-engineered arteries. We conclude with suggestions for future research and opportunities for therapeutic intervention in genetic and acquired elastinopathies.
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Ba, X., Y. Meng, Y. Huang, S. Y. Kwak, S. Ge, Y. Qin, E. DiMasi, Helga Füredi-Milhofer, N. Pernodet, and Miriam Rafailovich. "In Vitro Biomineralization Induced by Self-Assembled Extracellular Matrix Proteins." Key Engineering Materials 361-363 (November 2007): 427–30. http://dx.doi.org/10.4028/www.scientific.net/kem.361-363.427.
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Extracellular matrix (ECM) proteins play an essential role during biomineralization in bone and engineered tissues. In a previous study [1], we showed that calcite preferentially nucleated on pure elastin fibers. However, the actual cellular ECM fibers are composed of a combination of proteins, primarily collagen, fibronectin and some elastin. Here we follow the calcium carbonate- and calcium phosphate- mineralization process in vitro when these ECM proteins are combined and determine the differences between these proteins in the biomineralization process. The surface morphology and mechanical properties of the protein fibers during the early stages were probed by atomic force microscopy (AFM) and shear modulation force microscopy (SMFM). The nucleation of the mineral crystals on the protein matrices was investigated by scanning electron microscopy (SEM). Preliminary data showed that the moduli of all protein fibers increased at the early stages, with collagen having the largest increase in supersaturated calcium bicarbonate solution. In metastable calcium phosphate solutions the modulus of the mixed elastin-fibronectin fibres increased to a greater extent than the moduli of the fibers composed of the single proteins. Longer exposure in the mineral solutions led to the formation of crystals templated along the self-assembled fiber structures.
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Mercer, R. R., and J. D. Crapo. "Spatial distribution of collagen and elastin fibers in the lungs." Journal of Applied Physiology 69, no. 2 (August 1, 1990): 756–65. http://dx.doi.org/10.1152/jappl.1990.69.2.756.
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Surface tension forces acting on the thin-wall alveolar septa and the collagen-elastin fiber network are major factors in lung parenchymal micromechanics. Quantitative serial section analysis and morphometric evaluations of planar sections were used to determine the spatial location of collagen and elastin fibers in Sprague-Dawley rat and normal human lung samples. A large concentration of connective tissue fibers was located in the alveolar duct wall in both species. For rats, the tissue densities of collagen and elastin fibers located within 10 microns of an alveolar duct were 13 and 9%, respectively. In human lung samples, the tissue densities of collagen and elastin fibers within 20 microns of an alveolar duct were 18 and 16%, respectively. In both species, bands of elastin fibers formed a continuous ring around each alveolar mouth. In human lungs, elastin fibers were found to penetrate significantly deeper into alveolar septal walls than they did in rat lungs. The concentration of connective tissue elements in the alveolar duct walls of both species is consistent with their proposed roles as the principal load-bearing elements of the lung parenchyma.
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Moset Zupan, Andreja Moset, Carolyn Nietupski, and Stacey C. Schutte. "Cyclic Adenosine Monophosphate Eliminates Sex Differences in Estradiol-Induced Elastin Production from Engineered Dermal Substitutes." International Journal of Molecular Sciences 22, no. 12 (June 14, 2021): 6358. http://dx.doi.org/10.3390/ijms22126358.
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Lack of adult cells’ ability to produce sufficient amounts of elastin and assemble functional elastic fibers is an issue for creating skin substitutes that closely match native skin properties. The effects of female sex hormones, primarily estrogen, have been studied due to the known effects on elastin post-menopause, thus have primarily included older mostly female populations. In this study, we examined the effects of female sex hormones on the synthesis of elastin by female and male human dermal fibroblasts in engineered dermal substitutes. Differences between the sexes were observed with 17β-estradiol treatment alone stimulating elastin synthesis in female substitutes but not male. TGF-β levels were significantly higher in male dermal substitutes than female dermal substitutes and the levels did not change with 17β-estradiol treatment. The male dermal substitutes had a 1.5-fold increase in cAMP concentration in the presence of 17β-estradiol compared to no hormone controls, while cAMP concentrations remained constant in the female substitutes. When cAMP was added in addition to 17β-estradiol and progesterone in the culture medium, the sex differences were eliminated, and elastin synthesis was upregulated by 2-fold in both male and female dermal substitutes. These conditions alone did not result in functionally significant amounts of elastin or complete elastic fibers. The findings presented provide insights into differences between male and female cells in response to female sex steroid hormones and the involvement of the cAMP pathway in elastin synthesis. Further explorations into the signaling pathways may identify better targets to promote elastic fiber synthesis in skin substitutes.
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González, José M., Ana M. Briones, Beatriz Somoza, Craig J. Daly, Elisabet Vila, Barry Starcher, John C. McGrath, M. Carmen González, and Silvia M. Arribas. "Postnatal alterations in elastic fiber organization precede resistance artery narrowing in SHR." American Journal of Physiology-Heart and Circulatory Physiology 291, no. 2 (August 2006): H804—H812. http://dx.doi.org/10.1152/ajpheart.01262.2005.
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Resistance artery narrowing and stiffening are key elements in the pathogenesis of essential hypertension, but their origin is not completely understood. In mesenteric resistance arteries (MRA) from spontaneously hypertensive rats (SHR), we have shown that inward remodeling is associated with abnormal elastic fiber organization, leading to smaller fenestrae in the internal elastic lamina. Our current aim is to determine whether this alteration is an early event that precedes vessel narrowing, or if elastic fiber reorganization in SHR arteries occurs because of the remodeling process itself. Using MRA from 10-day-old, 30-day-old, and 6-mo-old SHR and normotensive Wistar Kyoto rats, we investigated the time course of the development of structural and mechanical alterations (pressure myography), elastic fiber organization (confocal microscopy), and amount of elastin (radioimmunoassay for desmosine) and collagen (picrosirius red). SHR MRA had an impairment of fenestrae enlargement during the first month of life. In 30-day-old SHR, smaller fenestrae and more packed elastic fibers in the internal elastic lamina were paralleled by increased wall stiffness. Collagen and elastin levels were unaltered at this age. MRA from 6-mo-old SHR also had smaller fenestrae and a denser network of adventitial elastic fibers, accompanied by increased collagen content and vessel narrowing. At this age, elastase digestion was less effective in SHR MRA, suggesting a lower susceptibility of elastic fibers to enzymatic degradation. These data suggest that abnormal elastic fiber deposition in SHR increases resistance artery stiffness at an early age, which might participate in vessel narrowing later in life.
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Bochicchio, Brigida, Maria Rosaria Armenante, Maria Antonietta Crudele, and Antonietta Pepe. "Molecular Determinants for the Self-Assembly of Elastin Peptides." Conference Papers in Science 2014 (August 21, 2014): 1–4. http://dx.doi.org/10.1155/2014/214235.
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Elastin and elastin-related peptides have great potential in the biomaterial field, because of their peculiar mechanical properties and spontaneous self-assembling behavior. Depending on their sequences and under appropriate experimental conditions, they are able to self-assemble in different fiber morphologies, including amyloid-like fibers. In this work, we will review recent data on elastin peptides derived from exon 30-coded domain of human tropoelastin. This domain has been shown to be fundamental for the correct assembly of elastin. However, the N-terminal region forms amyloid-like fibers, while the C-terminal fragment forms elastin-like fibers. A rationale for the varied aggregation pattern has been sought in the molecular structure of the peptides. Minimal differences in the sequences, adopting alternative conformations, are shown to be responsible for the observed data.
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Boëté, Quentin, Ming Lo, Kiao-Ling Liu, Guillaume Vial, Emeline Lemarié, Maxime Rougelot, Iris Steuckardt, et al. "Physiological Impact of a Synthetic Elastic Protein in Arterial Diseases Related to Alterations of Elastic Fibers: Effect on the Aorta of Elastin-Haploinsufficient Male and Female Mice." International Journal of Molecular Sciences 23, no. 21 (November 3, 2022): 13464. http://dx.doi.org/10.3390/ijms232113464.
Full textAbstract:
Elastic fibers, made of elastin (90%) and fibrillin-rich microfibrils (10%), are the key extracellular components, which endow the arteries with elasticity. The alteration of elastic fibers leads to cardiovascular dysfunctions, as observed in elastin haploinsufficiency in mice (Eln+/-) or humans (supravalvular aortic stenosis or Williams–Beuren syndrome). In Eln+/+ and Eln+/- mice, we evaluated (arteriography, histology, qPCR, Western blots and cell cultures) the beneficial impact of treatment with a synthetic elastic protein (SEP), mimicking several domains of tropoelastin, the precursor of elastin, including hydrophobic elasticity-related domains and binding sites for elastin receptors. In the aorta or cultured aortic smooth muscle cells from these animals, SEP treatment induced a synthesis of elastin and fibrillin-1, a thickening of the aortic elastic lamellae, a decrease in wall stiffness and/or a strong trend toward a reduction in the elastic lamella disruptions in Eln+/- mice. SEP also modified collagen conformation and transcript expressions, enhanced the aorta constrictive response to phenylephrine in several animal groups, and, in female Eln+/- mice, it restored the normal vasodilatory response to acetylcholine. SEP should now be considered as a biomimetic molecule with an interesting potential for future treatments of elastin-deficient patients with altered arterial structure/function.
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Sobin, S. S., Y. C. Fung, and H. M. Tremer. "Collagen and elastin fibers in human pulmonary alveolar walls." Journal of Applied Physiology 64, no. 4 (April 1, 1988): 1659–75. http://dx.doi.org/10.1152/jappl.1988.64.4.1659.
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The morphology and morphometric data of collagen and elastin fibers in the pulmonary alveolar walls are presented. Specimens were obtained from postmortem lungs quick-frozen at specified transpulmonary pressures. Collagen was stained by silver, and elastin was stained by orcein. Photomicrographs were composed by computer. Young lungs typically show small collagen fibers that radiate from the "posts," whereas larger fiber bundles traverse the septum irrespective of capillary blood vessels. In older lungs, rings of collagen around the posts appear enlarged. Elastin bundles do not show obvious variation in pattern with age and inflation pressure. Statistical frequency distributions of the fiber width and curvature are both skewed, but the square root of the width and the cube root of the curvature have approximate normal distributions. Typically, for young lungs at transpulmonary pressure of 4 cmH2O, the mean of (width)1/2 (in micron1/2) for collagen fibers is 0.952 +/- 0.242 (SD), that of (curvature)1/3 (in micron-1/3) is 0.349 +/- 0.094. The corresponding values for elastin are 0.986 +/- 0.255 and 0.395 +/- 0.094.
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Shin, Seung Jae, and Hiromi Yanagisawa. "Recent updates on the molecular network of elastic fiber formation." Essays in Biochemistry 63, no. 3 (August 8, 2019): 365–76. http://dx.doi.org/10.1042/ebc20180052.
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Abstract Elastic fibers confer elasticity and recoiling to tissues and organs and play an essential role in induction of biochemical responses in a cell against mechanical forces derived from the microenvironment. The core component of elastic fibers is elastin (ELN), which is secreted as the monomer tropoelastin from elastogenic cells, and undergoes self-aggregation, cross-linking and deposition on to microfibrils, and assemble into insoluble ELN polymers. For elastic fibers to form, a microfibril scaffold (primarily formed by fibrillin-1 (FBN1)) is required. Numerous elastic fiber-associated proteins are involved in each step of elastogenesis and they instruct and/or facilitate the elastogenesis processes. In this review, we designated five proteins as key molecules in elastic fiber formation, including ELN, FBN1, fibulin-4 (FBLN4), fibulin-5 (FBLN5), and latent TGFβ-binding protein-4 (LTBP4). ELN and FBN1 serve as building blocks for elastic fibers. FBLN5, FBLN4 and LTBP4 have been demonstrated to play crucial roles in elastogenesis through knockout studies in mice. Using these molecules as a platform and expanding the elastic fiber network through the generation of an interactome map, we provide a concise review of elastogenesis with a recent update as well as discuss various biological functions of elastic fiber-associated proteins beyond elastogenesis in vivo.
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Gibson, Mark A., Jaliya S. Kumaratilake, and Edward G. Cleary. "Immunohistochemical and Ultrastructural Localization of MP78/70 (βig-h3) in Extracellular Matrix of Developing and Mature Bovine Tissues." Journal of Histochemistry & Cytochemistry 45, no. 12 (December 1997): 1683–96. http://dx.doi.org/10.1177/002215549704501212.
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MP78/70 is a matrix protein, with 78-kD and 70-kD isoforms, which was initially identified in bovine tissue extracts designed to solubilize elastin-associated microfibrils. Peptide analysis has shown that MP78/70 is closely related to the human protein, βig-h3. In the present study an antibody raised to a synthetic βig-h3 peptide was shown specifically to identify MP78/70 in purified form and in bovine tissue extracts. This is consistent with MP78/70 and βig-h3 being the bovine and human forms, respectively, of the same protein. The antibody was further affinity-purified on MP78/70 bound to Sepharose and used to localize the protein in a range of bovine tissues. Immunofluorescence showed that MP78/70 was localized to collagen fibers in tissues such as developing nuchal ligament, aorta and lung, and mature cornea; to reticular fibers in fetal spleen; and to capsule and tubule basement membranes in developing kidney. No general localization to elastic fibers was observed. The staining pattern in most tissues more closely resembled that of Type VI collagen, which occurs as collagen fiber-associated microfibrils, than that of fibrillin-1, a component of elastin-associated microfibrils. However, MP78/70 appeared to be less widely distributed than Type VI collagen. Immunoelectron microscopy showed that MP78/70 was predominantly found in loose association with collagen fibers in most tissues examined and was also located on the surface of the capsule basement membrane in developing kidney. Double labeling experiments indicated that MP78/70 is co-distributed with Type VI collagen microfibrils located in these regions. In some elastic tissues significant immunolabel was detected in regions of interface between collagen fibers and fibrillin-containing microfibrils of adjacent elastic fibers, and at the outer margins of the latter structures. Overall, the evidence points to MP78/70 having a bridging function, perhaps in association with Type VI collagen microfibrils, linking or stabilizing the interaction between interstitial collagen fibrils and other matrix structures, including some basement membranes and elastin-associated microfibrils.
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Runci Anastasi, Michele, Piero Cascone, Giuseppe Pio Anastasi, Giuseppe Santoro, Fabiana Nicita, Giacomo Picciolo, Angelo Favaloro, Giuseppina Rizzo, and Giuseppina Cutroneo. "Articular Disc of a Human Temporomandibular Joint: Evaluation through Light Microscopy, Immunofluorescence and Scanning Electron Microscopy." Journal of Functional Morphology and Kinesiology 6, no. 1 (February 25, 2021): 22. http://dx.doi.org/10.3390/jfmk6010022.
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The extracellular matrix of the articular disc in a temporomandibular joint (TMJ) is composed mainly of collagen I and elastin. The collagen is important for resisting tensile forces, while the elastin is responsible to maintain the shape after deformation. We studied the orientation of collagen and elastin in a normal human temporomandibular joint disc by light microscopy, immunofluorescence and scanning electron microscopy. Our results demonstrated that collagen and elastin run parallel to each other in the intermediate zone with an anteroposterior orientation. From here, the orientation of two fibers groups changes into a disordered arrangement in the transition zone. Numerous elastic fibers cross with the collagen fibers, defining an interwoven knitted arrangement. The evaluation of the disc–condyle relationship shows that the medial margin of the articular disc is inserted directly at the superficial layer of the mandibular condylar cartilage. Therefore, the tensile properties of the TMJ disc are expressed in the directions corresponding to the orientation of the collagen fibers, and the complex orientation of elastin with the collagen determines the maintaining of the shape after the stresses by the joint movements. Moreover, the direct anatomical relationship between the articular disc and the mandibular condyle makes a decisive contribution to the understanding of TMJ movements.
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Mercer, R. R., and J. D. Crapo. "Structural changes in elastic fibers after pancreatic elastase administration in hamsters." Journal of Applied Physiology 72, no. 4 (April 1, 1992): 1473–79. http://dx.doi.org/10.1152/jappl.1992.72.4.1473.
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Ultrastructural changes in lung parenchymal elastic fibers were studied morphometrically 1, 4, and 12 wk after a single 12-unit dose of pancreatic elastase and in a saline-instilled control group. The mean linear intercept of the parenchymal air spaces was increased in the 1-, 4-, and 12-wk post-elastase instillation groups compared with age-matched controls. The volume of alveolar connective tissue fibers predominantly composed of elastin (elastic fibers) was decreased by 35% 1 wk after the instillation of elastase but returned to control levels by 4 wk. Although the total volume of elastic fibers was normal 12 wk after instillation of elastase, the volume of elastic fibers in alveolar entrance rings remained significantly reduced. In serial sections of elastic fibers, numerous gaps or separations in the normally continuous band of elastic fibers that encircle each alveolus were identified 1 wk after elastase instillation. There were 169 +/- 8 (SE), 62 +/- 32, and 12 +/- 6 gaps per millimeter of alveolar entrance ring circumference at 1, 4, and 12 wk, respectively, in the elastase-treated groups. The number of gaps at 12 wk was equivalent to two gaps or discontinuities in the elastic fibers of every alveolar entrance ring. No gaps or separations in elastic fibers were detected at 1, 4, or 12 wk in the control groups. These defects occur in concordance with the progression of air space enlargement and presumably contribute to the progression of air space enlargement that occurs after the elastin content of the tissue has returned to normal.
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Zanetti, Miriam, Paola Braghetta, Patrizia Sabatelli, Isabella Mura, Roberto Doliana, Alfonso Colombatti, Dino Volpin, Paolo Bonaldo, and Giorgio M. Bressan. "EMILIN-1 Deficiency Induces Elastogenesis and Vascular Cell Defects." Molecular and Cellular Biology 24, no. 2 (January 15, 2004): 638–50. http://dx.doi.org/10.1128/mcb.24.2.638-650.2004.
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ABSTRACT EMILINs constitute a family of genes of the extracellular matrix with high structural similarity. Four genes have been identified so far in human and mouse. To gain insight into the function of this gene family, EMILIN-1 has been inactivated in the mouse by gene targeting. The homozygous animals were fertile and did not show obvious abnormalities. However, histological and ultrastructural examination revealed alterations of elastic fibers in aorta and skin. Formation of elastic fibers by mutant embryonic fibroblasts in culture was also abnormal. Additional alterations were observed in cell morphology and anchorage of endothelial and smooth muscle cells to elastic lamellae. Considering that EMILIN-1 is adhesive for cells and that the protein binds to elastin and fibulin-5, EMILIN-1 may regulate elastogenesis and vascular cell maintenance by stabilizing molecular interactions between elastic fiber components and by endowing elastic fibers with specific cell adhesion properties.
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McEnaney, Ryan M., Dylan D. McCreary, Nolan O. Skirtich, Elizabeth A. Andraska, Ulka Sachdev, and Edith Tzeng. "Elastic Laminar Reorganization Occurs with Outward Diameter Expansion during Collateral Artery Growth and Requires Lysyl Oxidase for Stabilization." Cells 11, no. 1 (December 21, 2021): 7. http://dx.doi.org/10.3390/cells11010007.
Full textAbstract:
When a large artery becomes occluded, hemodynamic changes stimulate remodeling of arterial networks to form collateral arteries in a process termed arteriogenesis. However, the structural changes necessary for collateral remodeling have not been defined. We hypothesize that deconstruction of the extracellular matrix is essential to remodel smaller arteries into effective collaterals. Using multiphoton microscopy, we analyzed collagen and elastin structure in maturing collateral arteries isolated from ischemic rat hindlimbs. Collateral arteries harvested at different timepoints showed progressive diameter expansion associated with striking rearrangement of internal elastic lamina (IEL) into a loose fibrous mesh, a pattern persisting at 8 weeks. Despite a 2.5-fold increase in luminal diameter, total elastin content remained unchanged in collaterals compared with control arteries. Among the collateral midzones, baseline elastic fiber content was low. Outward remodeling of these vessels with a 10–20 fold diameter increase was associated with fractures of the elastic fibers and evidence of increased wall tension, as demonstrated by the straightening of the adventitial collagen. Inhibition of lysyl oxidase (LOX) function with β-aminopropionitrile resulted in severe fragmentation or complete loss of continuity of the IEL in developing collaterals. Collateral artery development is associated with permanent redistribution of existing elastic fibers to accommodate diameter growth. We found no evidence of new elastic fiber formation. Stabilization of the arterial wall during outward remodeling is necessary and dependent on LOX activity.
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Kagan, H. M., C. A. Vaccaro, R. E. Bronson, S. S. Tang, and J. S. Brody. "Ultrastructural immunolocalization of lysyl oxidase in vascular connective tissue." Journal of Cell Biology 103, no. 3 (September 1, 1986): 1121–28. http://dx.doi.org/10.1083/jcb.103.3.1121.
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The localization of lysyl oxidase was examined in calf and rat aortic connective tissue at the ultrastructural level using polyclonal chicken anti-lysyl oxidase and gold conjugated rabbit anti-chicken immunoglobulin G to identify immunoreactive sites. Electron microscopy of calf aortic specimens revealed discrete gold deposits at the interface between extracellular bundles of amorphous elastin and the microfibrils circumferentially surrounding these bundles. The antibody did not react with microfibrils which were distant from the interface with elastin. There was negligible deposition of gold within the bundles of amorphous elastin and those few deposits seen at these sites appeared to be associated with strands of microfibrils. Lysyl oxidase was similarly localized in newborn rat aorta at the interface between microfibrils and nascent elastin fibers. Gold deposits were not seen in association with extracellular collagen fibers even after collagen-associated proteoglycans had been degraded by chondroitinase ABC. However, the antibody did recognize collagen-bound lysyl oxidase in collagen fibers prepared from purified collagen to which the enzyme had been added in vitro. No reaction product was seen if the anti-lysyl oxidase was preadsorbed with purified lysyl oxidase illustrating the specificity of the antibody probe. The present results are consistent with a model of elastogenesis predicting the radial growth of the elastin fiber by the deposition and crosslinking of tropoelastin units at the fiber-microfibril interface.
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Cyril, Divya, Amelia Giugni, Saie Sunil Bangar, Melika Mirzaeipoueinak, Dipika Shrivastav, Mirit Sharabi, Joanne L. Tipper, and Javad Tavakoli. "Elastic Fibers in the Intervertebral Disc: From Form to Function and toward Regeneration." International Journal of Molecular Sciences 23, no. 16 (August 11, 2022): 8931. http://dx.doi.org/10.3390/ijms23168931.
Full textAbstract:
Despite extensive efforts over the past 40 years, there is still a significant gap in knowledge of the characteristics of elastic fibers in the intervertebral disc (IVD). More studies are required to clarify the potential contribution of elastic fibers to the IVD (healthy and diseased) function and recommend critical areas for future investigations. On the other hand, current IVD in-vitro models are not true reflections of the complex biological IVD tissue and the role of elastic fibers has often been ignored in developing relevant tissue-engineered scaffolds and realistic computational models. This has affected the progress of IVD studies (tissue engineering solutions, biomechanics, fundamental biology) and translation into clinical practice. Motivated by the current gap, the current review paper presents a comprehensive study (from the early 1980s to 2022) that explores the current understanding of structural (multi-scale hierarchy), biological (development and aging, elastin content, and cell-fiber interaction), and biomechanical properties of the IVD elastic fibers, and provides new insights into future investigations in this domain.
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Akiyama, Mari. "Roles of Two F-Box Proteins: FBXL14 in the Periosteum and FBXW2 at Elastic Fibers." Osteology 3, no. 1 (January 5, 2023): 1–10. http://dx.doi.org/10.3390/osteology3010001.
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I previously reported that F-box/leucine-rich repeat protein 14 (FBXL14) expressed in periosteum-derived cells, and F-box and WD-40 domain-containing protein 2 (FBXW2) in the periosteum form a fiber-like structure. Here, two culture medium conditions, that is, media with and without ascorbic acid, were compared during explant culture. In the absence of ascorbic acid, the expression patterns of osteocalcin, FBXW2, and elastin were compared using fluorescent immunostaining during weeks 3–5. By observing the periosteum, cambium layer and bone, I demonstrated FBXL14 expression in micro-vessels and bone lacuna. Fluorescent immunostaining revealed that, without ascorbic acid, the FBXL14 layer was thin. Conversely, in the presence of ascorbic acid, FBXL14 formed a thick membrane-like structure inside the periosteum, and the multilayer of periosteum-derived cells (PDCs) was strong. The expression patterns of osteocalcin and FBXW2 were similar. Elastin retained its fiber structure for up to five weeks. Although osteocalcin and FBXW2 were expressed in regions similar to elastin, they could not retain their fiber structures. In conclusion, FBXL14 appears to play a role in preparing a native scaffold for forming a multilayered sheet of PDCs inside the periosteum. FBXW2 and osteocalcin appear to separate from elastic fibers during calcification.
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Morris, S. M., P. J. Stone, and G. L. Snider. "Electron microscopic study of human lung tissue after in vitro exposure to elastase." Journal of Histochemistry & Cytochemistry 41, no. 6 (June 1993): 851–66. http://dx.doi.org/10.1177/41.6.8315277.
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Much of the experimental evidence supporting the hypothesis that pulmonary emphysema results from an imbalance between elastases and anti-elastases in the lung comes from animal models. The present study was designed to examine the effects on human lung tissue of the two elastases that have been most widely used to produce these animal models. Lung tissue was exposed in vitro to human neutrophil elastase (HNE) or porcine pancreatic elastase (PPE). Although both enzymes solubilized protein at similar rates, PPE solubilized elastin five times faster than did HNE. Ultrastructurally, HNE-exposed tissue exhibited fewer damaged elastic fibers as well as some fibers that were damaged at the edges, whereas the interior of the fiber appeared intact. Elastic fibers showing damage only at the periphery were not seen in tissue exposed to PPE. Immunocytochemical studies in which antibodies to HNE and PPE were applied to thin sections of Lowicryl-embedded tissue indicated that both of these elastases could be detected in association with elastic fibers, but only in areas of the fiber that showed morphological evidence of elastase injury. Both HNE and PPE removed fibronectin from basement membranes (as determined by loss of binding of fibronectin antibodies after exposure to elastase), but neither elastase was detected on basement membrane. Loss of epithelial cells usually accompanied elastic fiber damage by HNE but not PPE.
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Chen, Huan, Mikhail N. Slipchenko, Yi Liu, Xuefeng Zhao, Ji-Xin Cheng, Yoram Lanir, and Ghassan S. Kassab. "Biaxial deformation of collagen and elastin fibers in coronary adventitia." Journal of Applied Physiology 115, no. 11 (December 1, 2013): 1683–93. http://dx.doi.org/10.1152/japplphysiol.00601.2013.
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The microstructural deformation-mechanical loading relation of the blood vessel wall is essential for understanding the overall mechanical behavior of vascular tissue in health and disease. We employed simultaneous mechanical loading-imaging to quantify in situ deformation of individual collagen and elastin fibers on unstained fresh porcine coronary adventitia under a combination of vessel inflation and axial extension loading. Specifically, the specimens were imaged under biaxial loads to study microscopic deformation-loading behavior of fibers in conjunction with morphometric measurements at the zero-stress state. Collagen fibers largely orientate in the longitudinal direction, while elastin fibers have major orientation parallel to collagen, but with additional orientation angles in each sublayer of the adventitia. With an increase of biaxial load, collagen fibers were uniformly stretched to the loading direction, while elastin fibers gradually formed a network in sublayers, which strongly depended on the initial arrangement. The waviness of collagen decreased more rapidly at a circumferential stretch ratio of λθ= 1.0 than at λθ= 1.5, while most collagen became straightened at λθ= 1.8. These microscopic deformations imply that the longitudinally stiffer adventitia is a direct result of initial fiber alignment, and the overall mechanical behavior of the tissue is highly dependent on the corresponding microscopic deformation of fibers. The microstructural deformation-loading relation will serve as a foundation for micromechanical models of the vessel wall.
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Lin, Ying-Ju, An-Ni Chen, Xi Jiang Yin, Chunxiang Li, and Chih-Chien Lin. "Human Microfibrillar-Associated Protein 4 (MFAP4) Gene Promoter: A TATA-Less Promoter That Is Regulated by Retinol and Coenzyme Q10 in Human Fibroblast Cells." International Journal of Molecular Sciences 21, no. 21 (November 9, 2020): 8392. http://dx.doi.org/10.3390/ijms21218392.
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Elastic fibers are one of the major structural components of the extracellular matrix (ECM) in human connective tissues. Among these fibers, microfibrillar-associated protein 4 (MFAP4) is one of the most important microfibril-associated glycoproteins. MFAP4 has been found to bind with elastin microfibrils and interact directly with fibrillin-1, and then aid in elastic fiber formation. However, the regulations of the human MFAP4 gene are not so clear. Therefore, in this study, we firstly aimed to analyze and identify the promoter region of the human MFAP4 gene. The results indicate that the human MFAP4 promoter is a TATA-less promoter with tissue- and species-specific properties. Moreover, the promoter can be up-regulated by retinol and coenzyme Q10 (coQ10) in Detroit 551 cells.
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Su, Hengjie, Tomoko Fujiwara, and Joel D. Bumgardner. "A Study of Combining Elastin in the Chitosan Electrospinning to Increase the Mechanical Strength and Bioactivity." Marine Drugs 19, no. 3 (March 22, 2021): 169. http://dx.doi.org/10.3390/md19030169.
Full textAbstract:
While electrospun chitosan membranes modified to retain nanofibrous morphology have shown promise for use in guided bone regeneration applications in in vitro and in vivo studies, their mechanical tear strengths are lower than commercial collagen membranes. Elastin, a natural component of the extracellular matrix, is a protein with extensive elastic property. This work examined the incorporation of elastin into electrospun chitosan membranes to improve their mechanical tear strengths and to further mimic the native extracellular composition for guided bone regeneration (GBR) applications. In this work, hydrolyzed elastin (ES12, Elastin Products Company, USA) was added to a chitosan spinning solution from 0 to 4 wt% of chitosan. The chitosan–elastin (CE) membranes were examined for fiber morphology using SEM, hydrophobicity using water contact angle measurements, the mechanical tear strength under simulated surgical tacking, and compositions using Fourier-transform infrared spectroscopy (FTIR) and post-spinning protein extraction. In vitro experiments were conducted to evaluate the degradation in a lysozyme solution based on the mass loss and growth of fibroblastic cells. Chitosan membranes with elastin showed significantly thicker fiber diameters, lower water contact angles, up to 33% faster degradation rates, and up to seven times higher mechanical strengths than the chitosan membrane. The FTIR spectra showed stronger amide peaks at 1535 cm−1 and 1655 cm−1 in membranes with higher concentrated elastin, indicating the incorporation of elastin into electrospun fibers. The bicinchoninic acid (BCA) assay demonstrated an increase in protein concentration in proportion to the amount of elastin added to the CE membranes. In addition, all the CE membranes showed in vitro biocompatibility with the fibroblasts.
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Chyatte, Douglas, Jeffrey Reilly, and David M. Tilson. "Morphometric Analysis of Reticular and Elastin Fibers in the Cerebral Arteries of Patients with Intracranial Aneurysms." Neurosurgery 26, no. 6 (June 1, 1990): 939–43. http://dx.doi.org/10.1227/00006123-199006000-00003.
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Abstract Elastin and reticular fibers were identified using standard histological stains in middle cerebral arteries taken from patients who had died from aneurysmal subarachnoid hemorrhage and control patients who did not have cerebral aneurysms, Examination of cerebral arteries from normal individuals revealed a dense network of fine reticular fibers in the arterial media that were uniformly distributed. Computerized morphometric analysis indicated that reticular fibers in the arterial media of cerebral arteries were significantly decreased in patients with aneurysms. In addition, these fibers were irregularly distributed and shortened when compared to those seen in control arteries. In both patients with aneurysms and control patients, elastin fibers were limited almost exclusively to the internal elastin lamina. No differences were observed in the appearance or content of elastin fibers in control patients and patients with aneurysm. Although other explanations cannot be excluded, these observations are consistent with the hypothesis that “intrinsic“ abnormalities in the walls of cerebral arteries lead to conditions that favor the formation and rupture of cerebral aneurysms.
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Knyazkova, A. I., A. A. Samarinova, V. V. Nikolaev, Y. V. Kistenev, and A. V. Borisov. "Features two-photon microscopy for analysis fluorescent properties of elastin fibers rats in vivo." Izvestiya vysshikh uchebnykh zavedenii. Fizika, no. 11 (2021): 128–33. http://dx.doi.org/10.17223/00213411/64/11/128.
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This paper presents the results of in vivo visualization of elastin fibers of the papillary layer of rat skin obtained using two-photon microscopy. It is shown that, when approximating the fluorescence decay curve by a two-exponential model, the obtained parameters for rat dermis elastin and human elastin fibers have similar distributions.
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Fornieri, C., M. Baccarani-Contri, D. Quaglino, and I. Pasquali-Ronchetti. "Lysyl oxidase activity and elastin/glycosaminoglycan interactions in growing chick and rat aortas." Journal of Cell Biology 105, no. 3 (September 1, 1987): 1463–69. http://dx.doi.org/10.1083/jcb.105.3.1463.
Full textAbstract:
Hydrophobic tropoelastin molecules aggregate in vitro in physiological conditions and form fibers very similar to natural ones (Bressan, G. M., I. Pasquali Ronchetti, C. Fornieri, F. Mattioli, I. Castellani, and D. Volpin, 1986, J. Ultrastruct. Molec. Struct. Res., 94:209-216). Similar hydrophobic interactions might be operative in in vivo fibrogenesis. Data are presented suggesting that matrix glycosaminoglycans (GAGs) prevent spontaneous tropoelastin aggregation in vivo, at least up to the deamination of lysine residues on tropoelastin by matrix lysyl oxidase. Lysyl oxidase inhibitors beta-aminopropionitrile, aminoacetonitrile, semicarbazide, and isonicotinic acid hydrazide were given to newborn chicks, to chick embryos, and to newborn rats, and the ultrastructural alterations of the aortic elastic fibers were analyzed and compared with the extent of the enzyme inhibition. When inhibition was greater than 65% all chemicals induced alterations of elastic fibers in the form of lateral aggregates of elastin, which were always permeated by cytochemically and immunologically recognizable GAGs. The number and size of the abnormal elastin/GAGs aggregates were proportional to the extent of lysyl oxidase inhibition. The phenomenon was independent of the animal species. All data suggest that, upon inhibition of lysyl oxidase, matrix GAGs remain among elastin molecules during fibrogenesis by binding to positively charged amino groups on elastin. Newly synthesized and secreted tropoelastin has the highest number of free epsilon amino groups, and, therefore, the highest capability of binding to GAGs. These polyanions, by virtue of their great hydration and dispersing power, could prevent random spontaneous aggregation of hydrophobic tropoelastin in the extracellular space.
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Pepe, Antonietta, and Brigida Bochicchio. "An Elastin-Derived Self-Assembling Polypeptide." Journal of Soft Matter 2013 (June 13, 2013): 1–7. http://dx.doi.org/10.1155/2013/732157.
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Elastin is an extracellular matrix protein responsible for the elastic properties of organs and tissues, the elastic properties being conferred to the protein by the presence of elastic fibers. In the perspective of producing tailor-made biomaterials of potential interest in nanotechnology and biotechnology fields, we report a study on an elastin-derived polypeptide. The choice of the polypeptide sequence encoded by exon 6 of Human Tropoelastin Gene is dictated by the peculiar sequence of the polypeptide. As a matter of fact, analogously to elastin, it is constituted of a hydrophobic region (GLGAFPAVTFPGALVPGG) and of a more hydrophilic region rich of lysine and alanine residues (VADAAAAYKAAKA). The role played by the two different regions in triggering the adoption of beta-turn and beta-sheet conformations is herein discussed and demonstrated to be crucial for the self-aggregation properties of the polypeptide.
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Tsuruga, E., K. Irie, and T. Yajima. "Gene Expression and Accumulation of Fibrillin-1, Fibrillin-2, and Tropoelastin in Cultured Periodontal Fibroblasts." Journal of Dental Research 81, no. 11 (November 2002): 771–75. http://dx.doi.org/10.1177/0810771.
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The elastic system fibers consist of three types—oxytalan, elaunin, and elastic fibers—differing in their relative microfibril and elastin contents. All three types are found in human gingiva, but human periodontal ligaments contain only elastin-free fibers. We examined cultured human gingival fibroblasts (HGF) and cultured human periodontal ligament fibroblasts (HPLF) to determine the gene expression of fibrillin-1 and fibrillin-2 (the major components of microfibrils) and of tropoelastin. In addition, we assessed the degree of accumulation of these proteins in the extracellular matrix. Northern blot analysis revealed that the level of expression of fibrillin-1 and fibrillin-2 was higher in HGF than in HPLF. However, examination of matrix samples from HGF and HPLF cell layers showed that there was no difference in fibrillin-1 accumulation, although fibrillin-2 accumulated to a much greater extent in the HGF-derived matrix. Tropoelastin was expressed only in and around HGF. These results show a correlation between gene expression and the accumulation of tropoelastin and fibrillin-2 in HGF.
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Hammond, Thomas H., Steven D. Gray, John Butler, Ruixia Zhou, and Elizabeth Hammond. "Age- and gender-related elastin distribution changes in human vocal folds." Otolaryngology–Head and Neck Surgery 119, no. 4 (October 1998): 314–22. http://dx.doi.org/10.1016/s0194-5998(98)70071-3.
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The composition of the lamina propria in human vocal folds has been shown to affect vocal performance. Elastin plays a significant role in the biomechanical effects of the lamina propria. We obtained 19 larynges from the state medical examiner from subjects whose cause of death was unrelated to the trachea and laryngeal regions. The sample contained male and female subjects in the infant, adult, and geriatric age groups. We stained the vocal folds for elastin with Verhoeff's elastic tissue stain and studied them with use of an image analysis system configured for light microscopy. Distributions of elastin were measured from superficial to deep within the lamina propria (from epithelium to vocal muscle). These elastin distributions were then compared with the use of statistical software. The data showed that there was an increase in elastin content from the infant through geriatric stages. No gender-related differences were found. Infant folds had about 23% of the elastin found in adults, and geriatric subjects had about 879% of the elastin found in adults. Both of these results were statistically significant ( p < 0.05). The distributions were consistent with previous observations that the lamina propria is a layered structure with most of the elastin present in the intermediate layer. This layer was larger in geriatric subjects than in adult and pediatric subjects. We observed that the fiber diameter appeared to be larger in geriatric subjects (this observation is currently being verified with electron microscopy) whereas smaller, spiraled fibers appeared in pediatric subjects.
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Martín-López, Javier, Consuelo Pérez-Rico, Selma Benito-Martínez, Bárbara Pérez-Köhler, Julia Buján, and Gemma Pascual. "The Role of the Stromal Extracellular Matrix in the Development of Pterygium Pathology: An Update." Journal of Clinical Medicine 10, no. 24 (December 17, 2021): 5930. http://dx.doi.org/10.3390/jcm10245930.
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Pterygium is a benign fibrovascular lesion of the bulbar conjunctiva with frequent involvement of the corneal limbus. Its pathogenesis has been mainly attributed to sun exposure to ultraviolet-B radiation. Obtained evidence has shown that it is a complex and multifactorial process which involves multiple mechanisms such as oxidative stress, dysregulation of cell cycle checkpoints, induction of inflammatory mediators and growth factors, angiogenic stimulation, extracellular matrix (ECM) disorders, and, most likely, viruses and hereditary changes. In this review, we aim to collect all authors’ experiences and our own, with respect to the study of fibroelastic ECM of pterygium. Collagen and elastin are intrinsic indicators of physiological and pathological states. Here, we focus on an in-depth analysis of collagen (types I and III), as well as the main constituents of elastic fibers (tropoelastin (TE), fibrillins (FBNs), and fibulins (FBLNs)) and the enzymes (lysyl oxidases (LOXs)) that carry out their assembly or crosslinking. All the studies established that changes in the fibroelastic ECM occur in pterygium, based on the following facts: An increase in the synthesis and deposition of an immature form of collagen type III, which showed the process of tissue remodeling. An increase in protein levels in most of the constituents necessary for the development of elastic fibers, except FBLN4, whose biological roles are critical in the binding of the enzyme LOX, as well as FBN1 for the development of stable elastin. There was gene overexpression of TE, FBN1, FBLN5, and LOXL1, while the expression of LOX and FBLN2 and -4 remained stable. In conclusion, collagen and elastin, as well as several constituents involved in elastic fiber assembly are overexpressed in human pterygium, thus, supporting the hypothesis that there is dysregulation in the synthesis and crosslinking of the fibroelastic component, constituting an important pathogenetic mechanism for the development of the disease.
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Wan, William, and Rudolph L. Gleason. "Dysfunction in elastic fiber formation in fibulin-5 null mice abrogates the evolution in mechanical response of carotid arteries during maturation." American Journal of Physiology-Heart and Circulatory Physiology 304, no. 5 (March 1, 2013): H674—H686. http://dx.doi.org/10.1152/ajpheart.00459.2012.
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Elastin fragmentation is a common characteristic of vascular diseases, such as abdominal aortic aneurysms, peripheral arterial disease, and aortic dissection. Examining growth and remodeling in the presence of dysfunctional elastic fibers provides insight into the adaptive or maladaptive changes that tissues undergo in compensating for structural deficiencies. This study used the maturation of fibulin-5 knockout (KO) and wild-type mice to study the effects of fragmented elastic fibers on the growth and remodeling of carotid arteries. The microstructural content and organization and the biaxial mechanical behavior of common carotid arteries were measured, and parameter estimation performed from KO and WT mice aged 3, 4, 8, and 13 wk. Gross measurements and biaxial tests revealed significant differences in pressure-diameter behavior, in vivo axial stretch, opening angle, compliance, and wall stresses during maturation of wild-type arteries, but little change in these values in KO mice. Multiphoton microscopy used to image collagen fibers across the vessel wall in pressurized and stretched arteries suggests that there is little variation in fiber angles between different ages. Parameter estimation revealed significant differences in material parameters between genotypes and age groups. This study suggests that neonatal formation and cross-linking of functional elastic fibers, followed by increases in artery size due to growth with little remodeling of the elastic fibers, endow arteries with large distensibility and contribute to the evolution of mechanical behavior of arteries during maturation. Dysfunction in neonatal formation of elastic fibers abrogates many of the changes in mechanical response that take place during the maturation.
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Hoareau, Marie, Naïma El Kholti, Romain Debret, and Elise Lambert. "Zebrafish as a Model to Study Vascular Elastic Fibers and Associated Pathologies." International Journal of Molecular Sciences 23, no. 4 (February 14, 2022): 2102. http://dx.doi.org/10.3390/ijms23042102.
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Many extensible tissues such as skin, lungs, and blood vessels require elasticity to function properly. The recoil of elastic energy stored during a stretching phase is provided by elastic fibers, which are mostly composed of elastin and fibrillin-rich microfibrils. In arteries, the lack of elastic fibers leads to a weakening of the vessel wall with an increased risk to develop cardiovascular defects such as stenosis, aneurysms, and dissections. The development of new therapeutic molecules involves preliminary tests in animal models that recapitulate the disease and whose response to drugs should be as close as possible to that of humans. Due to its superior in vivo imaging possibilities and the broad tool kit for forward and reverse genetics, the zebrafish has become an important model organism to study human pathologies. Moreover, it is particularly adapted to large scale studies, making it an attractive model in particular for the first steps of investigations. In this review, we discuss the relevance of the zebrafish model for the study of elastic fiber-related vascular pathologies. We evidence zebrafish as a compelling alternative to conventional mouse models.
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Boizot, Jérémy, Mélaine Minville-Walz, Dieter Peter Reinhardt, Marielle Bouschbacher, Pascal Sommer, Dominique Sigaudo-Roussel, and Romain Debret. "FBN2 Silencing Recapitulates Hypoxic Conditions and Induces Elastic Fiber Impairment in Human Dermal Fibroblasts." International Journal of Molecular Sciences 23, no. 3 (February 5, 2022): 1824. http://dx.doi.org/10.3390/ijms23031824.
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Most chronic wounds are characterized by varying degrees of hypoxia and low partial pressures of O2 that may favor the development of the wound and/or delay healing. However, most studies regarding extracellular matrix remodeling in wound healing are conducted under normoxic conditions. Here, we investigated the consequences of hypoxia on elastic network formation, both in a mouse model of pressure-induced hypoxic ulcer and in human primary fibroblasts cultured under hypoxic conditions. In vitro, hypoxia inhibited elastic fiber synthesis with a reduction in fibrillin-2 expression at the mRNA and protein levels. Lysyl oxidase maturation was reduced, concomitant with lower enzymatic activity. Fibrillin-2 and lysyl oxidase could interact directly, whereas the downregulation of fibrillin-2 was associated with deficient lysyl oxidase maturation. Elastic fibers were not synthesized in the hypoxic inflammatory tissues resulting from in vivo pressure-induced ulcer. Tropoelastin and fibrillin-2 were expressed sparsely in hypoxic tissues stained with carbonic anhydrase IX. Different hypoxic conditions in culture resulted in the arrest of elastic fiber synthesis. The present study demonstrated the involvement of FBN2 in regulating elastin deposition in adult skin models and described the specific impact of hypoxia on the elastin network without consequences on collagen and fibronectin networks.
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Cavalcante, Francisco S. A., Satoru Ito, Kelly Brewer, Hiroaki Sakai, Adriano M. Alencar, Murilo P. Almeida, José S. Andrade, Arnab Majumdar, Edward P. Ingenito, and Béla Suki. "Mechanical interactions between collagen and proteoglycans: implications for the stability of lung tissue." Journal of Applied Physiology 98, no. 2 (February 2005): 672–79. http://dx.doi.org/10.1152/japplphysiol.00619.2004.
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Collagen and elastin are thought to dominate the elasticity of the connective tissue including lung parenchyma. The glycosaminoglycans on the proteoglycans may also play a role because osmolarity of interstitial fluid can alter the repulsive forces on the negatively charged glycosaminoglycans, allowing them to collapse or inflate, which can affect the stretching and folding pattern of the fibers. Hence, we hypothesized that the elasticity of lung tissue arises primarily from 1) the topology of the collagen-elastin network and 2) the mechanical interaction between proteoglycans and fibers. We measured the quasi-static, uniaxial stress-strain curves of lung tissue sheets in hypotonic, normal, and hypertonic solutions. We found that the stress-strain curve was sensitive to osmolarity, but this sensitivity decreased after proteoglycan digestion. Images of immunofluorescently labeled collagen networks showed that the fibers follow the alveolar walls that form a hexagonal-like structure. Despite the large heterogeneity, the aspect ratio of the hexagons at 30% uniaxial strain increased linearly with osmolarity. We developed a two-dimensional hexagonal network model of the alveolar structure incorporating the mechanical properties of the collagen-elastin fibers and their interaction with proteoglycans. The model accounted for the stress-strain curves observed under all experimental conditions. The model also predicted how aspect ratio changed with osmolarity and strain, which allowed us to estimate the Young's modulus of a single alveolar wall and a collagen fiber. We therefore identify a novel and important role for the proteoglycans: they stabilize the collagen-elastin network of connective tissues and contribute to lung elasticity and alveolar stability at low to medium lung volumes.
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Staiculescu, Marius Catalin, Austin J. Cocciolone, Jesse D. Procknow, Jungsil Kim, and Jessica E. Wagenseil. "Comparative gene array analyses of severe elastic fiber defects in late embryonic and newborn mouse aorta." Physiological Genomics 50, no. 11 (November 1, 2018): 988–1001. http://dx.doi.org/10.1152/physiolgenomics.00080.2018.
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Elastic fibers provide reversible elasticity to the large arteries and are assembled during development when hemodynamic forces are increasing. Mutations in elastic fiber genes are associated with cardiovascular disease. Mice lacking expression of the elastic fiber genes elastin ( Eln−/−), fibulin-4 ( Efemp2−/−), or lysyl oxidase ( Lox−/−) die at birth with severe cardiovascular malformations. All three genetic knockout models have elastic fiber defects, aortic wall thickening, and arterial tortuosity. However, Eln−/− mice develop arterial stenoses, while Efemp2−/− and Lox−/− mice develop ascending aortic aneurysms. We performed comparative gene array analyses of these three genetic models for two vascular locations and developmental stages to determine differentially expressed genes and pathways that may explain the common and divergent phenotypes. We first examined arterial morphology and wall structure in newborn mice to confirm that the lack of elastin, fibulin-4, or lysyl oxidase expression provided the expected phenotypes. We then compared gene expression levels for each genetic model by three-way ANOVA for genotype, vascular location, and developmental stage. We found three genes upregulated by genotype in all three models, Col8a1, Igfbp2, and Thbs1, indicative of a common response to severe elastic fiber defects in developing mouse aorta. Genes that are differentially regulated by vascular location or developmental stage in all three models suggest mechanisms for location or stage-specific disease pathology. Comparison of signaling pathways enriched in all three models shows upregulation of integrins and matrix proteins involved in early wound healing, but not of mature matrix molecules such as elastic fiber proteins or fibrillar collagens.
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Oue, Takaharu, and Prem Puri. "Abnormalities of elastin and elastic fibers in infantile hypertrophic pyloric stenosis." Pediatric Surgery International 15, no. 8 (November 24, 1999): 540–42. http://dx.doi.org/10.1007/s003830050665.
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A. Matthews, Jamil, Gary E. Wnek, David G. Simpson, and Gary L. Bowlin. "Vascular Tissue Engineering Utilizing Electrospun Matrices: Microscopic Evaluations." Microscopy and Microanalysis 7, S2 (August 2001): 142–43. http://dx.doi.org/10.1017/s1431927600026787.
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The development of a seamless, collagen-based vascular prosthetic scaffolding (< 4 mm I.D.) has been accomplished using an electrospinning fiber production technique (Patents Pending). Electrospinning is the deliberate application of the phenomenon of electrostatic spraying which occurs when electrical forces at the surface of the polymer solution overcome the surface tension, creating a splay. The splay produces fibers with diameters in the nano-scale range (<500 nm). The collagen-based scaffold production method (flexible, quick, and simple) utilizes the splaying of the collagen-based solution from a nozzle to a grounded rotating mandrel (4 mm O.D. cylindrical mandrel for the preliminary vascular tissue engineering). in splaying, the solvent evaporates creating nano-scale fibers of polymerized collagen (and elastin in some variations). The collagen fibers are collected on the mandrel forming a cylindrical tube (media equivalent scaffolding). to date, mixtures of collagen containing Type I and 80:20 Type l/Elastin have been utilized to produce vascular scaffolds of various thickness (50 - 2,000 microns).