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Journal articles on the topic 'Elastin'
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1
TASSLER, P. L., A. L. DELLON, and C. CANOUN. "Identification of Elastic Fibres in the Peripheral Nerve." Journal of Hand Surgery 19, no. 1 (February 1994): 48–54. http://dx.doi.org/10.1016/0266-7681(94)90049-3.
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Traditional histological staining techniques, as well as elastin-specific antibodies and electron microscopy, have been used to assess the distribution of elastin within the peripheral nerve. The location of the elastin identified by the VerHoeff-VanGiesen or Weigert stains has been shown to coincide with the unambiguous identilication of elastin by immunospecific stains and electron microscopy. Elastin is located in all three connective layers of the peripheral nerve. Thick elastic fibres, consisting of amorphous elastiu protein and microfibrils, are located consistently in the perineurium and, to a lesser extent, in the epineurium. The endoneurium contains small collections of elastic fibres widely distributed between the axons. Compared with collagen, the overall content of elastin, however, is small, suggesting that the visco-elastic properties of peripheral nerve may be due primarily to collagen.
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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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Trębacz, Hanna, and Angelika Barzycka. "Mechanical Properties and Functions of Elastin: An Overview." Biomolecules 13, no. 3 (March 22, 2023): 574. http://dx.doi.org/10.3390/biom13030574.
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Human tissues must be elastic, much like other materials that work under continuous loads without losing functionality. The elasticity of tissues is provided by elastin, a unique protein of the extracellular matrix (ECM) of mammals. Its function is to endow soft tissues with low stiffness, high and fully reversible extensibility, and efficient elastic–energy storage. Depending on the mechanical functions, the amount and distribution of elastin-rich elastic fibers vary between and within tissues and organs. The article presents a concise overview of the mechanical properties of elastin and its role in the elasticity of soft tissues. Both the occurrence of elastin and the relationship between its spatial arrangement and mechanical functions in a given tissue or organ are overviewed. As elastin in tissues occurs only in the form of elastic fibers, the current state of knowledge about their mechanical characteristics, as well as certain aspects of degradation of these fibers and their mechanical performance, is presented. The overview also outlines the latest understanding of the molecular basis of unique physical characteristics of elastin and, in particular, the origin of the driving force of elastic recoil after stretching.
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Fonck, E., G. Prod'hom, S. Roy, L. Augsburger, D. A. Rüfenacht, and N. Stergiopulos. "Effect of elastin degradation on carotid wall mechanics as assessed by a constituent-based biomechanical model." American Journal of Physiology-Heart and Circulatory Physiology 292, no. 6 (June 2007): H2754—H2763. http://dx.doi.org/10.1152/ajpheart.01108.2006.
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Arteries display a nonlinear anisotropic behavior dictated by the elastic properties and structural arrangement of its main constituents, elastin, collagen, and vascular smooth muscle. Elastin provides for structural integrity and for the compliance of the vessel at low pressure, whereas collagen gives the tensile resistance required at high pressures. Based on the model of Zulliger et al. (Zulliger MA, Rachev A, Stergiopulos N. Am J Physiol Heart Circ Physiol 287: H1335–H1343, 2004), which considers the contributions of elastin, collagen, and vascular smooth muscle cells (VSM) in an explicit form, we assessed the effects of enzymatic degradation of elastin on biomechanical properties of rabbit carotids. Pressure-diameter curves were obtained for controls and after elastin degradation, from which elastic and structural properties were derived. Data were fitted into the model of Zulliger et al. to assess elastic constants of elastin and collagen as well as the characteristics of the collagen engagement profile. The arterial segments were also prepared for histology to visualize and quantify elastin and collagen. Elastase treatment leads to a diameter enlargement, suggesting the existence of significant compressive prestresses within the wall. The elastic modulus was more ductile in treated arteries at low circumferential stretches and significantly greater at elevated circumferential stretches. Abrupt collagen fiber recruitment in elastase-treated arteries leads to a much stiffer vessel at high extensions. This change in collagen engagement properties results from structural alterations provoked by the degradation of elastin, suggesting a clear interaction between elastin and collagen, often neglected in previous constituent-based models of the arterial wall.
5
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.
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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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Hoareau, Marie, Naïma El Kholti, Romain Debret, and Elise Lambert. "Characterization of the Zebrafish Elastin a (elnasa12235) Mutant: A New Model of Elastinopathy Leading to Heart Valve Defects." Cells 12, no. 10 (May 21, 2023): 1436. http://dx.doi.org/10.3390/cells12101436.
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Elastic fibers are extracellular macromolecules that provide resilience and elastic recoil to elastic tissues and organs in vertebrates. They are composed of an elastin core surrounded by a mantle of fibrillin-rich microfibrils and are essentially produced during a relatively short period around birth in mammals. Thus, elastic fibers have to resist many physical, chemical, and enzymatic constraints occurring throughout their lives, and their high stability can be attributed to the elastin protein. Various pathologies, called elastinopathies, are linked to an elastin deficiency, such as non-syndromic supravalvular aortic stenosis (SVAS), Williams–Beuren syndrome (WBS), and autosomal dominant cutis laxa (ADCL). To understand these diseases, as well as the aging process related to elastic fiber degradation, and to test potential therapeutic molecules in order to compensate for elastin impairments, different animal models have been proposed. Considering the many advantages of using zebrafish, we here characterize a zebrafish mutant for the elastin a paralog (elnasa12235) with a specific focus on the cardiovascular system and highlight premature heart valve defects at the adult stage.
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Nishizaki, Tomoyuki. "PKCε Increases Extracellular Elastin and Fibulin-5/DANCE in Dermal Fibroblasts." Cellular Physiology and Biochemistry 46, no. 1 (2018): 291–302. http://dx.doi.org/10.1159/000488430.
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Background/Aims: In the earlier study, the selective PKCε activator DCP-LA increased elastic fibres in the dermis of HR-1 hairless mice. As a process of elastic fibre formation, tropoelastin, an elastin monomer, is secreted into the extracellular space. Secreted tropoelastin is delivered to the microfibrils by fibulin-5/developmental arteries and neural crest epidermal growth factor-like (DANCE) and undergoes self-association. Then, tropoelastin assembles around the microfibrils, growing into elastin and elastic fibres by lysyl oxidase (LOX)- or LOX-like (LOXL)-mediated cross-linking. The present study was conducted to understand the mechanism underlying DCP-LA-induced increase in elastin/elastic fibre. Methods: Western blotting, immunocytochemistory, and real-time reverse transcription-polymerase chain reaction (RT-PCR) were carried out in cultured human dermal fibroblasts. PKCε, mammalian target of rapamycin complex (mTOR), and p70 S6 kinase (S6K) were knocked-down by transfecting each siRNA. Results: DCP-LA increased elastin and fibulin-5/DANCE in a treatment time (6-24 h)- and a bell-shaped concentration (1 nM-1 µM)-dependent manner in the culture medium of human dermal fibroblasts. DCP-LA markedly increased elastic fibres in the extracellular space of cultured fibroblasts. DCP-LA-induced increase in extracellular elastin and fibulin-5/DANCE was abolished by a PKC inhibitor or knocking-down PKCε. DCP-LA did not affect expression of mRNAs for tropoelastin and fiblin-5/DANCE in cultured fibroblasts. DCP-LA-induced increase in extracellular elastin and fibulin-5/DANCE was not inhibited by the protein synthesis inhibitor cycloheximide or by knocking-down mTOR and S6K. DCP-LA never increased extracellular elastin in the presence of elastase, that breaks down elastin. An inhibitor of matrix metalloproteinase 9, that degrades multiple extracellular matrix components including elastin, had no effect on the basal levels and the DCP-LA-induced increase levels of extracellular elastin. Conclusion: The results of the present study indicate that PKCε, activated by DCP-LA, increases elastin and fibulin-5/DANCE in the extracellular space of cultured fibroblasts by the mechanism independent of transcriptional and translational modulation or inhibition of elastolysis.
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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.
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Sambani, Kyriaki, Stylianos Vasileios Kontomaris, and Dido Yova. "Atomic Force Microscopy Imaging of Elastin Nanofibers Self-Assembly." Materials 16, no. 12 (June 11, 2023): 4313. http://dx.doi.org/10.3390/ma16124313.
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Elastin is an extracellular matrix protein, providing elasticity to the organs, such as skin, blood vessels, lungs and elastic ligaments, presenting self-assembling ability to form elastic fibers. The elastin protein, as a component of elastin fibers, is one of the major proteins found in connective tissue and is responsible for the elasticity of tissues. It provides resilience to the human body, assembled as a continuous mesh of fibers that require to be deformed repetitively and reversibly. Thus, it is of great importance to investigate the development of the nanostructural surface of elastin-based biomaterials. The purpose of this research was to image the self-assembling process of elastin fiber structure under different experimental parameters such as suspension medium, elastin concentration, temperature of stock suspension and time interval after the preparation of the stock suspension. atomic force microscopy (AFM) was applied in order to investigate how different experimental parameters affected fiber development and morphology. The results demonstrated that through altering a number of experimental parameters, it was possible to affect the self-assembly procedure of elastin fibers from nanofibers and the formation of elastin nanostructured mesh consisting of naturally occurring fibers. Further clarification of the contribution of different parameters on fibril formation will enable the design and control of elastin-based nanobiomaterials with predetermined characteristics.
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Powell, J. T. "Evidence against lung galaptin being important to the synthesis or organization of the elastic fibril." Biochemical Journal 252, no. 2 (June 1, 1988): 447–52. http://dx.doi.org/10.1042/bj2520447.
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Previously it has been suggested that galaptin, an endogenous beta-galactoside-binding lectin, may function in the organization of lung elastic fibres. Galaptin was not present in preparations of rat or porcine lung elastic fibrils, neither did it bind to any of the fibril-associated proteins when these were separated by SDS/polyacrylamide-gel electrophoresis. Elastin and galaptin synthesis and secretion were investigated in lung fibroblast cultures and in anatomically preserved slices from developing rat lung. In both systems the synthesis and secretion of elastin was unmodified by the presence of beta-galactosides or antigalaptin in the culture medium. The synthesis of galaptin was unmodified by the presence of anti-elastin or beta-aminoproprionitrile in the culture medium. Cultured fibroblasts secreted elastin but only trivial amounts of galaptin. When cultures were treated with iodoacetamide (10(-5)M) galaptin synthesis was maintained but elastin synthesis ceased. These results argue against galaptin having an important role in the synthesis, secretion or organization of the elastic fibril.
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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.
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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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Paulovic, R. P., and R. A. Anwar. "Developmental regulation of the mRNAs for elastins a, b and c in foetal-calf nuchal ligament and aorta." Biochemical Journal 261, no. 1 (July 1, 1989): 227–32. http://dx.doi.org/10.1042/bj2610227.
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The data presented clearly suggest that relative amounts of mRNAs for elastins a, b and c are developmentally regulated in foetal-calf nuchal ligament and aorta and that this regulation is tissue-specific. In nuchal ligament, at earlier stages of foetal development, the relative amounts of mRNAs for elastins a and b are very low. After the foetal age of about 6 months the relative amount of mRNA for elastin b begins to increase. This is followed by an increase in the relative amount of mRNA for elastin a. In aorta, with increasing foetal age, the relative amounts of mRNAs for elastins b and c increase and decrease alternately. The relative amounts of mRNA for elastin a remain low, with only marginal increases with foetal age. A possible self-aggregation role of elastin a in elastogenesis is proposed.
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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).
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Ohnishi, Y., M. Akiyama, S. Tajima, A. Ishibashi, and Y. Seyama. "Elastic Nevus With Normal Expression of Elastin and Elastin-Related Proteins mRNAs." Dermatology 198, no. 3 (1999): 307–9. http://dx.doi.org/10.1159/000018138.
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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.
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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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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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Yu, J. "Elastic tissues of the intervertebral disc." Biochemical Society Transactions 30, no. 6 (November 1, 2002): 848–52. http://dx.doi.org/10.1042/bst0300848.
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Elastic fibres have been generally considered to play no significant role in the mechanical functioning of the intervertebral disc since earlier studies reported that the elastic fibre network was sparse and irregular. However, a recent study has reported that the network is highly organized and that the distribution and orientation of elastic fibres varies from region to region. In the annulus, elastic fibres appear densely distributed in the region between the lamellae and also in ‘bridges’ across the lamellae. They are also organized in the nucleus where long straight fibres are radially oriented and anchor perpendicularly or obliquely into the cartilaginous endplate. Immunohisto-chemistry using specific antibodies indicates that elastin is present in the network, as is fibrillin. Biochemical studies show, however, that the amino acid composition of the residue remaining after alkaline (NaOH) extraction or CNBr digestion contains a higher concentration of polar amino acids than ligamentum nuchal elastin. The composition of the residue suggests that disc elastin may cross-link strongly with some other matrix components. With such coupling, it is thought that elastic fibres could play a significant mechanical role even though overall elastin is less than 5% of the total dry weight of the disc.
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Li, Fei, Xuan Li, Yue-tang Wang, Cun-tao Yu, Gang Yin, Xiu-yu Chen, Shihua Zhao, Wei Wang, and Qi Gao. "The Etiological Heterogeneity of Bicuspid Aortopathy between Ascending and Root Morphotype." Heart Surgery Forum 23, no. 6 (December 22, 2020): E913—E919. http://dx.doi.org/10.1532/hsf.3333.
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Background: Valve-related hemodynamics and intrinsically regulated matrix proteases are 2 determined pathogenetic factors associated with medial elastin degeneration in bicuspid aortopathy. This study analyzed the association between elastic fiber deterioration and the 2 pathogenetic factors in ascending and root morphotypes, aiming to elucidate the etiological heterogeneity between the 2 morphotypes. Methods: Four-dimensional flow cardiac magnetic resonance was used to measure the regional wall shear stress (WSS) on the ascending aorta, and matrix metalloproteinase (MMP) expression was assessed by immunoblotting. After histopathology analysis of aortic tissue, we assessed whether elevated regional WSS and increased MMP expression corresponded with medial elastin thinning. Results: Increased regional WSS corresponded with medial elastin thinning in both morphotypes. Increased expression of different MMP isoforms corresponded with medial elastin degeneration in bicuspid aortopathy. The significantly increased expression of MMP-2 corresponded with a decrease of elastic fiber thickness in the ascending morphotype (P = .046), whereas elastic fiber thinning was associated with high levels of MMP-3 expression (P = .012) in the root morphotype. No association was observed between regional WSS and MMP expression. Conclusion: There is no difference in the effect of valve-related hemodynamics between ascending and root morphotype, and MMPs are not involved in the process of elastic fiber degeneration induced by increased WSS. The increased expression of different MMP isoforms was observed in the context of elastic fiber degeneration between the 2 morphotypes, implying that heterogeneity between them is revealed in the different intrinsic pathway of medial elastin degradation.
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Bland, Richard D., Robert Ertsey, Lucia M. Mokres, Liwen Xu, Berit E. Jacobson, Shu Jiang, Cristina M. Alvira, Marlene Rabinovitch, Eric S. Shinwell, and Anjali Dixit. "Mechanical ventilation uncouples synthesis and assembly of elastin and increases apoptosis in lungs of newborn mice." American Journal of Physiology-Lung Cellular and Molecular Physiology 294, no. 1 (January 2008): L3—L14. http://dx.doi.org/10.1152/ajplung.00362.2007.
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Prolonged mechanical ventilation (MV) with O2-rich gas inhibits lung growth and causes excess, disordered accumulation of lung elastin in preterm infants, often resulting in chronic lung disease (CLD). Using newborn mice, in which alveolarization occurs postnatally, we designed studies to determine how MV with either 40% O2or air might lead to dysregulated elastin production and impaired lung septation. MV of newborn mice for 8 h with either 40% O2or air increased lung mRNA for tropoelastin and lysyl oxidase, relative to unventilated controls, without increasing lung expression of genes that regulate elastic fiber assembly (lysyl oxidase-like-1, fibrillin-1, fibrillin-2, fibulin-5, emilin-1). Serine elastase activity in lung increased fourfold after MV with 40% O2, but not with air. We then extended MV with 40% O2to 24 h and found that lung content of tropoelastin protein doubled, whereas lung content of elastin assembly proteins did not change (lysyl oxidases, fibrillins) or decreased (fibulin-5, emilin-1). Quantitative image analysis of lung sections showed that elastic fiber density increased by 50% after MV for 24 h, with elastin distributed throughout the walls of air spaces, rather than at septal tips, as in control lungs. Dysregulation of elastin was associated with a threefold increase in lung cell apoptosis (TUNEL and caspase-3 assays), which might account for the increased air space size previously reported in this model. Our findings of increased elastin synthesis, coupled with increased elastase activity and reduced lung abundance of proteins that regulate elastic fiber assembly, could explain altered lung elastin deposition, increased apoptosis, and defective septation, as observed in CLD.
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BROWN-AUGSBURGER, Patricia, Thomas BROEKELMANN, Joel ROSENBLOOM, and Robert P. MECHAM. "Functional domains on elastin and microfibril-associated glycoprotein involved in elastic fibre assembly." Biochemical Journal 318, no. 1 (August 15, 1996): 149–55. http://dx.doi.org/10.1042/bj3180149.
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Studies in vitro suggest that the C-terminus of tropoelastin mediates elastin polymerization through an interaction with microfibril-associated proteins. In this study we have used cultured auricular chondrocytes as a model system to examine whether this interaction is critical for elastic fibre formation in vivo. Auricular chondrocytes, which deposit an abundant elastic fibre matrix, were cultured in the presence of Fab fragments of antibodies directed against the C-terminus (CTe) or an N-terminal domain (ATe) of tropoelastin. Immunofluorescent staining of the extracellular matrix deposited by the cells showed that the CTe antibody inhibited the deposition of elastin without affecting microfibril structure. Cells grown under identical conditions in the presence of ATe, however, formed fibres that stained normally for both elastin and microfibril proteins. Chondrocytes cultured in the presence of microfibril-associated glycoprotein (MAGP):21–35, an antibody directed against a domain near the N-terminus of MAGP, did not organize tropoelastin into fibres. However, immunostaining for MAGP and fibrillin revealed normal microfibrils. In agreement with the immunofluorescence staining patterns, fewer elastin-specific cross-links, indicative of insoluble elastin, were detected in the extracellular matrix of cells cultured in the presence of CTe. The medium from these cultures, however, contained more soluble elastin, consistent with an antibody-induced alteration of elastin assembly but not its synthesis. Northern analysis of antibody-treated and control cultures substantiated equivalent levels of tropoelastin mRNA. These results confirm that the C-terminus of tropoelastin interacts with microfibrils during the assembly of elastic fibres. Further, the results suggest that the interaction between tropoelastin and microfibrils might be mediated by a domain involving the N-terminal half of MAGP.
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Reichheld, Sean E., Lisa D. Muiznieks, Fred W. Keeley, and Simon Sharpe. "Direct observation of structure and dynamics during phase separation of an elastomeric protein." Proceedings of the National Academy of Sciences 114, no. 22 (May 15, 2017): E4408—E4415. http://dx.doi.org/10.1073/pnas.1701877114.
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Despite its growing importance in biology and in biomaterials development, liquid–liquid phase separation of proteins remains poorly understood. In particular, the molecular mechanisms underlying simple coacervation of proteins, such as the extracellular matrix protein elastin, have not been reported. Coacervation of the elastin monomer, tropoelastin, in response to heat and salt is a critical step in the assembly of elastic fibers in vivo, preceding chemical cross-linking. Elastin-like polypeptides (ELPs) derived from the tropoelastin sequence have been shown to undergo a similar phase separation, allowing formation of biomaterials that closely mimic the material properties of native elastin. We have used NMR spectroscopy to obtain site-specific structure and dynamics of a self-assembling elastin-like polypeptide along its entire self-assembly pathway, from monomer through coacervation and into a cross-linked elastic material. Our data reveal that elastin-like hydrophobic domains are composed of transient β-turns in a highly dynamic and disordered chain, and that this disorder is retained both after phase separation and in elastic materials. Cross-linking domains are also highly disordered in monomeric and coacervated ELP3 and form stable helices only after chemical cross-linking. Detailed structural analysis combined with dynamic measurements from NMR relaxation and diffusion data provides direct evidence for an entropy-driven mechanism of simple coacervation of a protein in which transient and nonspecific intermolecular hydrophobic contacts are formed by disordered chains, whereas bulk water and salt are excluded.
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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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Muiznieks, Lisa D., Anthony S. Weiss, and Fred W. Keeley. "Structural disorder and dynamics of elastinThis paper is one of a selection of papers published in this special issue entitled “Canadian Society of Biochemistry, Molecular & Cellular Biology 52nd Annual Meeting — Protein Folding: Principles and Diseases” and has undergone the Journal's usual peer review process." Biochemistry and Cell Biology 88, no. 2 (April 2010): 239–50. http://dx.doi.org/10.1139/o09-161.
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Elastin is a self-assembling, extracellular-matrix protein that is the major provider of tissue elasticity. Here we review structural studies of elastin from over four decades, and draw together evidence for solution flexibility and conformational disorder that is inherent in all levels of structural organization. The characterization of disorder is consistent with an entropy-driven mechanism of elastic recoil. We conclude that conformational disorder is a constitutive feature of elastin structure and function.
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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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XIONG, Jiang, Wei GUO, Ren WEI, Shang-wei ZUO, Xiao-ping LIU, and Tao ZHANG. "Elastic fiber regeneration in vitro and in vivo for treatment of experimental abdominal aortic aneurysm." Chinese Medical Journal 126, no. 3 (February 2013): 437–41. http://dx.doi.org/10.3760/cma.j.issn.0366-6999.20122151.
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Background The pathological characteristics of abdominal aortic aneurysm (AAA) involved the regression of extracellular matrix (ECM) in aortic walls, especially elastic structure in medial layer. As the major structural protein of aorta, elastin contributes to the extensibility and elastic recoil of the vessels. We hypothesized that overexpression of elastin in vessel walls might regenerate the elastic structure of ECM, restore the elastic structure of the aneurysmal wall, and eventually lead to a reduction of aortic diameters (ADs) in an experimental model of AAA. Methods Tropoelastin (TE) of Sprague Dawley (SD) rat was synthesized by reverse transcription polymerase chain reaction and used to construct adneviral vectors containing elastin precursor protein (AdTE-GFP). Cultured vascular smooth muscle cells (VSMCs) from aortas of male SD rats were transfected with AdTE-GFP, AdGFP, adenoviral vector (AdNull), and phosphate buffered saline (PBS). Immunofluorescence staining was performed to determine the expression of elastin in transfected cells. The expression of elastic fibers in ECM of VSMCs transfected with AdTE-GFP were detected by fluorescence microscopy and transmission electron microscopy (TEM) at 1, 3, and 5 days following gene transfer. The AAA vessel walls were infused with AdTE-GFP or an empty AdNull, or PBS directly into the aneurysmal lumen. ADs of the aneurysms were compared in infused aortas. Formation of new elastic fibers in vivo was assessed by hematoxylin and eosin, and elastic von-Giesson staining. Recombinant elastin-GFP in vivo was identified by immunohistochemical staining. Results Elastic fibers were increased both in ECM of VSMC and in vessel walls after gene transfer. Histological studies revealed that the AdTE-GFP-transduced aortas had elastic fiber regeneration in the aneurysmal walls. The AdTE-GFP-transduced aortas showed a decreased AD (23.04%±14.49%, P<0.01) in AAA vessel walls. Conclusions Elastic fibers have been successfully overexpressed both in vitro and in a rat model of AAA by a technique of gene transfer. The overexpression of elastic fibers within the aneurysmal tissue appeared to reverse the aneurysm dilatation in this model.
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Oberson, D., L. Desfontaines, H. Pezerat, W. Hornebeck, P. Sebastien, and C. Lafuma. "Inhibition of human leukocyte elastase by mineral dust particles." American Journal of Physiology-Lung Cellular and Molecular Physiology 270, no. 5 (May 1, 1996): L761—L771. http://dx.doi.org/10.1152/ajplung.1996.270.5.l761.
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After isolation, purification, and radiolabeling of elastin from baboon aorta and lung, the rates of hydrolysis of both 3H-labeled elastins by porcine pancreatic elastase (PPE or by human leukocyte elastase (HLE) were compared. PPE (30 nM) degraded aorta and lung elastins at rates of 40 and 75 micrograms/h, respectively, leading to their complete solubilization. In contrast, the low rate of hydrolysis of lung elastin (10 micrograms/h) by HLE was paradoxically accompanied with a fivefold decrease in the Michaelis constant value and became negligible after 1 h of incubation. Moreover, HLE adsorption isotherms showed that 0.87 nmol HLE was adsorbed on 1 mg of aorta elastin vs. 1.30 nmol/mg lung elastin. Also, increasing ionic strength was found to enhance the elastolytic potential of HLE toward lung elastin. Investigations were carried out to explain why baboon lung elastin exhibited low susceptibility to hydrolysis by HLE. Solubilization of lung elastin with PPE produced a residue that exhibited inhibitory capacity toward HLE when either 3H-labeled aorta elastin or succinyl trialanine nitroanilide was used as a substrate. When analyzed by transmission electron microscopy, this residue was found to consist of several mineral dust particles, mainly kaolinite (53%) of environmental origin. The HLE-inhibitory capacities of various mineral or coal mine dust particles were then analyzed. Mineral aluminium-silicate dusts were found to be potent HLE inhibitors: 5 micrograms of either kaolinite or montmorillonite totally abolished the activity of 0.45 micrograms of HLE. All these results allowed us to propose that HLE inhibition by aluminium-silicate dusts may be of importance in the pathogenesis of industrial pneumoconiosis and in opportunistic lung infections.
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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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Keeley, F. W., C. M. Bellingham, and K. A. Woodhouse. "Elastin as a self–organizing biomaterial: use of recombinantly expressed human elastin polypeptides as a model for investigations of structure and self–assembly of elastin." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 357, no. 1418 (February 28, 2002): 185–89. http://dx.doi.org/10.1098/rstb.2001.1027.
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Elastin is the major extracellular matrix protein of large arteries such as the aorta, imparting characteristics of extensibility and elastic recoil. Once laid down in tissues, polymeric elastin is not subject to turnover, but is able to sustain its mechanical resilience through thousands of millions of cycles of extension and recoil. Elastin consists of ca . 36 domains with alternating hydrophobic and cross–linking characteristics. It has been suggested that these hydrophobic domains, predominantly containing glycine, proline, leucine and valine, often occurring in tandemly repeated sequences, are responsible for the ability of elastin to align monomeric chains for covalent cross–linking. We have shown that small, recombinantly expressed polypeptides based on sequences of human elastin contain sufficient information to self–organize into fibrillar structures and promote the formation of lysine–derived cross–links. These cross–linked polypeptides can also be fabricated into membrane structures that have solubility and mechanical properties reminiscent of native insoluble elastin. Understanding the basis of the self–organizational ability of elastin–based polypeptides may provide important clues for the general design of self–assembling biomaterials.
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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.
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SEYAMA, Yoshiyuki, Saburo YAMASHITA, and Shogo TOKUDOME. "Study of Elastin." Journal of Japan Atherosclerosis Society 15, no. 3 (1987): 797–802. http://dx.doi.org/10.5551/jat1973.15.3_797.
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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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Lammers, Steven R., Phil H. Kao, H. Jerry Qi, Kendall Hunter, Craig Lanning, Joseph Albietz, Stephen Hofmeister, Robert Mecham, Kurt R. Stenmark, and Robin Shandas. "Changes in the structure-function relationship of elastin and its impact on the proximal pulmonary arterial mechanics of hypertensive calves." American Journal of Physiology-Heart and Circulatory Physiology 295, no. 4 (October 2008): H1451—H1459. http://dx.doi.org/10.1152/ajpheart.00127.2008.
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Extracellular matrix remodeling has been proposed as one mechanism by which proximal pulmonary arteries stiffen during pulmonary arterial hypertension (PAH). Although some attention has been paid to the role of collagen and metallomatrix proteins in affecting vascular stiffness, much less work has been performed on changes in elastin structure-function relationships in PAH. Such work is warranted, given the importance of elastin as the structural protein primarily responsible for the passive elastic behavior of these conduit arteries. Here, we study structure-function relationships of fresh arterial tissue and purified arterial elastin from the main, left, and right pulmonary artery branches of normotensive and hypoxia-induced pulmonary hypertensive neonatal calves. PAH resulted in an average 81 and 72% increase in stiffness of fresh and digested tissue, respectively. Increase in stiffness appears most attributable to elevated elastic modulus, which increased 46 and 65%, respectively, for fresh and digested tissue. Comparison between fresh and digested tissues shows that, at 35% strain, a minimum of 48% of the arterial load is carried by elastin, and a minimum of 43% of the change in stiffness of arterial tissue is due to the change in elastin stiffness. Analysis of the stress-strain behavior revealed that PAH causes an increase in the strains associated with the physiological pressure range but had no effect on the strain of transition from elastin-dominant to collagen-dominant behavior. These results indicate that mechanobiological adaptations of the continuum and geometric properties of elastin, in response to PAH, significantly elevate the circumferential stiffness of proximal pulmonary arterial tissue.
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Manohar, Advaitanand, Wen Shi, and Rashid A. Anwar. "Partial characterization of bovine elastin gene; comparison with the gene for human elastin." Biochemistry and Cell Biology 69, no. 2-3 (February 1, 1991): 185–92. http://dx.doi.org/10.1139/o91-027.
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A 14 kilobase (kb) genomic clone of the gene for bovine elastin, containing exons 1 and 2, has been characterized. This clone extends about 6.5 kb in the 5′ direction from the initiation codon and 978 nucleotides in the 3′ direction from exon 2. The size of the first intron is about 6.4 kb. The sequence immediately 5′ to the initiation codon is highly conserved between the genes for bovine and human elastins and contains a TATA box consensus sequence (ATAAA), CAAT, and Sp1 binding sites. Several putative AP-2 binding sites are also present. Comparative analysis of the sequences flanking the first exon in the genes for bovine and human elastins identified conserved sequences that may be regulatory control elements. A putative enhancer core sequence is present in the first intron of the genes for bovine and human elastins.Key words: elastin gene, elastin gene promoter, bovine.
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Arribas, Silvia M., Ana M. Briones, Catherine Bellingham, M. Carmen González, Mercedes Salaices, Kela Liu, Yanting Wang, and Aleksander Hinek. "Heightened aberrant deposition of hard-wearing elastin in conduit arteries of prehypertensive SHR is associated with increased stiffness and inward remodeling." American Journal of Physiology-Heart and Circulatory Physiology 295, no. 6 (December 2008): H2299—H2307. http://dx.doi.org/10.1152/ajpheart.00155.2008.
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Elastin is a major component of conduit arteries and a key determinant of vascular viscoelastic properties. Aberrant organization of elastic lamellae has been reported in resistance vessels from spontaneously hypertensive rats (SHR) before the development of hypertension. Hence, we have characterized the content and organization of elastic lamellae in conduit vessels of neonatal SHR in detail, comparing the carotid arteries from 1-wk-old SHR with those from Wistar-Kyoto (WKY) and Sprague Dawley (SD) rats. The general structure and mechanics were studied by pressure myography, and the internal elastic lamina organization was determined by confocal microscopy. Cyanide bromide-insoluble elastin scaffolds were also prepared from 1-mo-old SHR and WKY aortas to assess their weight, amino acid composition, three-dimensional lamellar organization, and mechanical characteristics. Carotid arteries from 1-wk-old SHR exhibited narrower lumen and greater intrinsic stiffness than those from their WKY and SD counterparts. These aberrations were associated with heightened elastin content and with a striking reduction in the size of the fenestrae present in the elastic lamellae. The elastin scaffolds isolated from SHR aortas also exhibited increased relative weight and stiffness, as well as the presence of peculiar trabeculae inside the fenestra that reduced their size. We suggest that the excessive and aberrant elastin deposited in SHR vessels during perinatal development alters their mechanical properties. Such abnormalities are likely to compromise vessel expansion during a critical period of growth and, at later stages, they could compromise hemodynamic function and participate in the development of systemic hypertension.
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Mizuno, Tomohiro, Donald A. G. Mickle, Chris G. Kiani, and Ren-Ke Li. "Overexpression of elastin fragments in infarcted myocardium attenuates scar expansion and heart dysfunction." American Journal of Physiology-Heart and Circulatory Physiology 288, no. 6 (June 2005): H2819—H2827. http://dx.doi.org/10.1152/ajpheart.00862.2004.
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Ventricular dilation after myocardial infarction can cause heart failure. Increasing strength and elasticity in the infarct region might prevent ventricular dilation. Because elastin provides strength, extensibility, and resilience to tissues and maintains tissue architecture, we studied the effect of elastin expression in the infarct on scar expansion and heart function. COS-7 cells transfected with a plasmid with an elastin gene fragment or a vector were seeded into a Gelfoam mesh and cultured. Mechanical stretch test ( n = 5/group) showed that the elastin mesh was more elastic ( P < 0.05) and tensile ( P < 0.05) than the vector mesh. In an in vivo study in rats, 6 days after left anterior descending coronary artery ligation, COS-7 cells (Cell group, n = 7) or COS-7 cells with elastin gene (Elastin group, n = 9) or vector (Vector group, n = 9) were transplanted into the infarct; infarcted rats served as controls ( n = 7). Over 8 wk the Cell group did not demonstrate effects on scar expansion and deterioration of heart function vs. controls. In contrast, infarct expansion was smaller and heart function was better maintained in the Elastin group vs. the Vector group ( P < 0.05). At 8 wk after cell transplantation Langendorff data showed that the Elastin group had greater ( P < 0.01) developed pressure and a smaller left ventricular volume than the Vector group. Western blot and histology showed accumulated elastin in the Elastin group infarct. Changing the extracellular matrix composition of a myocardial infarct by increasing elastin fragment content attenuated scar expansion, ventricular dilation, and onset of heart dysfunction.
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Shifren, Adrian, Anthony G. Durmowicz, Russell H. Knutsen, Gilles Faury, and Robert P. Mecham. "Elastin insufficiency predisposes to elevated pulmonary circulatory pressures through changes in elastic artery structure." Journal of Applied Physiology 105, no. 5 (November 2008): 1610–19. http://dx.doi.org/10.1152/japplphysiol.90563.2008.
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Elastin is a major structural component of large elastic arteries and a principal determinant of arterial biomechanical properties. Elastin loss-of-function mutations in humans have been linked to the autosomal-dominant disease supravalvular aortic stenosis, which is characterized by stenotic lesions in both the systemic and pulmonary circulations. To better understand how elastin insufficiency influences the pulmonary circulation, we evaluated pulmonary cardiovascular physiology in a unique set of transgenic and knockout mice with graded vascular elastin dosage (range 45–120% of wild type). The central pulmonary arteries of elastin-insufficient mice had smaller internal diameters ( P < 0.0001), thinner walls ( P = 0.002), and increased opening angles ( P = 0.002) compared with wild-type controls. Pulmonary circulatory pressures, measured by right ventricular catheterization, were significantly elevated in elastin-insufficient mice ( P < 0.0001) and showed an inverse correlation with elastin level. Although elastin-insufficient animals exhibited mild to moderate right ventricular hypertrophy ( P = 0.0001) and intrapulmonary vascular remodeling, the changes were less than expected, given the high right ventricular pressures, and were attenuated compared with those seen in hypoxia-induced models of pulmonary arterial hypertension. The absence of extensive pathological cardiac remodeling at the high pressures in these animals suggests a developmental adaptation designed to maintain right-sided cardiac output in a vascular system with altered elastin content.
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Subramaniam, K., H. Kumar, and M. H. Tawhai. "Evidence for age-dependent air-space enlargement contributing to loss of lung tissue elastic recoil pressure and increased shear modulus in older age." Journal of Applied Physiology 123, no. 1 (July 1, 2017): 79–87. http://dx.doi.org/10.1152/japplphysiol.00208.2016.
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As a normal part of mature aging, lung tissue undergoes microstructural changes such as alveolar air-space enlargement and redistribution of collagen and elastin away from the alveolar duct. The older lung also experiences an associated decrease in elastic recoil pressure and an increase in specific tissue elastic moduli, but how this relates mechanistically to microstructural remodeling is not well-understood. In this study, we use a structure-based mechanics analysis to elucidate the contributions of age-related air-space enlargement and redistribution of elastin and collagen to loss of lung elastic recoil pressure and increase in tissue elastic moduli. Our results show that age-related geometric changes can result in reduction of elastic recoil pressure and increase in shear and bulk moduli, which is consistent with published experimental data. All elastic moduli were sensitive to the distribution of stiffness (representing elastic fiber density) in the alveolar wall, with homogenous stiffness near the duct and through the septae resulting in a more compliant tissue. The preferential distribution of elastic proteins around the alveolar duct in the healthy young adult lung therefore provides for a more elastic tissue. NEW & NOTEWORTHY We use a structure-based mechanics analysis to correlate air-space enlargement and redistribution of elastin and collagen to age-related changes in the mechanical behavior of lung parenchyma. Our study highlights that both the cause (redistribution of elastin and collagen) and the structural effect (alveolar air-space enlargement) contribute to decline in lung tissue elastic recoil with age; these results are consistent with published data and provide a new avenue for understanding the mechanics of the older lung.
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Green, Ellen M., Jessica C. Mansfield, James S. Bell, and C. Peter Winlove. "The structure and micromechanics of elastic tissue." Interface Focus 4, no. 2 (April 6, 2014): 20130058. http://dx.doi.org/10.1098/rsfs.2013.0058.
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Elastin is a major component of tissues such as lung and blood vessels, and endows them with the long-range elasticity necessary for their physiological functions. Recent research has revealed the complexity of these elastin structures and drawn attention to the existence of extensive networks of fine elastin fibres in tissues such as articular cartilage and the intervertebral disc. Nonlinear microscopy, allowing the visualization of these structures in living tissues, is informing analysis of their mechanical properties. Elastic fibres are complex in composition and structure containing, in addition to elastin, an array of microfibrillar proteins, principally fibrillin. Raman microspectrometry and X-ray scattering have provided new insights into the mechanisms of elasticity of the individual component proteins at the molecular and fibrillar levels, but more remains to be done in understanding their mechanical interactions in composite matrices. Elastic tissue is one of the most stable components of the extracellular matrix, but impaired mechanical function is associated with ageing and diseases such as atherosclerosis and diabetes. Efforts to understand these associations through studying the effects of processes such as calcium and lipid binding and glycation on the mechanical properties of elastin preparations in vitro have produced a confusing picture, and further efforts are required to determine the molecular basis of such effects.
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White, J. F., J. L. Hughes, J. S. Kumaratilake, J. C. Fanning, M. A. Gibson, R. Krishnan, and E. G. Cleary. "Post-embedding methods for immunolocalization of elastin and related components in tissues." Journal of Histochemistry & Cytochemistry 36, no. 12 (December 1988): 1543–51. http://dx.doi.org/10.1177/36.12.3142951.
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Elastic tissue is composed of amorphous-appearing elastin and 12-nm diameter microfibrils, one component of which has recently been isolated and characterized as the 31 KD microfibril-associated glycoprotein MAGP. Monospecific antibodies to each of these components have been developed in this laboratory. The parameters that determine optimal localization of colloidal gold probes for post-embedding immunolabeling of elastic tissue components have been systematically studied in a variety of normal and developing tissues in mammals and birds. Protein A-gold probes stabilized with dextran have been shown to provide complexes that remain stable after more than 2 years. Conditions have been defined that permit precise localization within the extracellular matrix of antibodies to MAGP and to elastin, singly and together. Best results were obtained with acrylic resins (Lowicryl K4M or LR White). Fixation in glutaraldehyde or other aldehydic fixatives, with or without osmium, did not affect the immunostaining of elastic tissue with affinity-purified antibodies to tropoelastin, or to anti-[alpha-elastin] or anti-[alkali-insoluble elastin]. Immunostaining with the anti-MAGP antibody was less robust and was possible in tissues which had been fixed only lightly before embedding in Lowicryl K4M or LR White. This staining was enhanced by metaperiodate oxidation of the sections as well as by reduction of the tissues with sodium borohydride en bloc, followed by hyaluronidase digestion of the sections. The effects on immunostaining of a range of enzyme digestions have also been examined. Conditions have thus been defined that make possible detailed study of the relationship between elastic tissue, elastin-associated microfibrils, and other microfibrillar structures in normal and abnormal tissues during development and aging.
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Armentano, R. L., J. Levenson, J. G. Barra, E. I. Fischer, G. J. Breitbart, R. H. Pichel, and A. Simon. "Assessment of elastin and collagen contribution to aortic elasticity in conscious dogs." American Journal of Physiology-Heart and Circulatory Physiology 260, no. 6 (June 1, 1991): H1870—H1877. http://dx.doi.org/10.1152/ajpheart.1991.260.6.h1870.
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The elastic behavior of total elastin (EE) and collagen (EC) and the recruitment of collagen fibers (FC) supporting wall stress at a given transmural pressure level were assessed in seven conscious dogs using descending thoracic aortic pressure (microtransducer) and diameter (sonomicrometer) measurements. Stress-strain relationships values calculated at control and during bolus administration of angiotensin and nitroglycerin enabled quantification of angiotensin and nitroglycerin enabled quantification of elastic moduli of elastin (EE = 4.868 +/- 1.753 x 10(6) dyn/cm2; means +/- SD) and collagen (EC = 1,306 +/- 637 x 10(6) dyn/cm2) according to a biphasic model of elastin and collagen parallel arrangement. The FC was found to be 6.1 +/- 2.6% at a pressure level of 118 +/- 16 mmHg. Values for EE and EC were similar to those reported in in vitro studies and showed scarce variability. This approach provides a quantitative evaluation of elastin and collagen moduli in conscious animals and also permits the evaluation of FC, which may be of interest in studies of connective tissue diseases involving the aortic wall.
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Carvalho, Olga Maria de Silvério. "Sexual Dimorphism of Elastic Fibers in Prenatal Lung Mice." European Journal of Biology and Biotechnology 5, no. 3 (May 14, 2024): 8–15. http://dx.doi.org/10.24018/ejbio.2024.5.3.507.
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Scientific data has revealed the existence of lung gender differences and therefore sparked a renewed interest in understanding the underlying mechanisms and their effect in the healthy lung development and/or in pathological conditions. Elastic fibers have an important role in lung development during pre and post-natal stages, because a well-developed pulmonary elastic fibers favour pre-natal lung maturation and enhance alveolarization. Sexual differences studies on lung elastic fibers content are focused essentially on the post-natal stage, with scarce data on pre-natal lung development. Using an experimental mice model, we developed this research work to study gender differences in the lungs elastic fibers during gestational days E15-E19, using image analysis and elastin HPLC methodologies. Our results show significant sexual dimorphism in lung elastin and elastic fibers content pre-natal stage, which is more evident in the last two gestational days (E18 and E19). Female’s mice have more elastin and elastic fibers which could mean that the elastogenesis process begins earlier than males. These results are an important contributes to understand the underlying factors involved in physiology and lung development sexual difference.
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Goldman, Jeremy, Shu Q. Liu, and Brandon J. Tefft. "Anti-Inflammatory and Anti-Thrombogenic Properties of Arterial Elastic Laminae." Bioengineering 10, no. 4 (March 28, 2023): 424. http://dx.doi.org/10.3390/bioengineering10040424.
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Elastic laminae, an elastin-based, layered extracellular matrix structure in the media of arteries, can inhibit leukocyte adhesion and vascular smooth muscle cell proliferation and migration, exhibiting anti-inflammatory and anti-thrombogenic properties. These properties prevent inflammatory and thrombogenic activities in the arterial media, constituting a mechanism for the maintenance of the structural integrity of the arterial wall in vascular disorders. The biological basis for these properties is the elastin-induced activation of inhibitory signaling pathways, involving the inhibitory cell receptor signal regulatory protein α (SIRPα) and Src homology 2 domain-containing protein tyrosine phosphatase 1 (SHP1). The activation of these molecules causes deactivation of cell adhesion- and proliferation-regulatory signaling mechanisms. Given such anti-inflammatory and anti-thrombogenic properties, elastic laminae and elastin-based materials have potential for use in vascular reconstruction.
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Kuang, Ping-Ping, and Ronald H. Goldstein. "Regulation of elastin gene transcription by proteasome dysfunction." American Journal of Physiology-Cell Physiology 289, no. 3 (September 2005): C766—C773. http://dx.doi.org/10.1152/ajpcell.00525.2004.
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Elastin, a major extracellular matrix protein and the core component of elastic fiber, is essential to maintain lung structural integrity and normal physiological function. We previously found that the downregulation of elastin gene transcription by IL-1β is mediated via activation of NF-κB and CCAAT/enhancer binding protein (C/EBP)β, both targets of the ubiquitin-proteasome pathway. To further investigate the molecular mechanisms that underlie the control of elastin gene expression, we disrupted the ubiquitin-proteasome pathway with specific proteasome inhibitors. We found that specific proteasome inhibitors decreased the steady-state level of elastin mRNA in a dose-responsive manner. Run-on assay and promoter reporter study indicated that the proteasome inhibitor MG-132 repressed the rate of elastin transcription. MG-132 did not affect mRNA levels of NF-κB and C/EBPβ, or the nuclear presence of NF-κB, but markedly increased C/EBPβ isoforms, including liver-enriched transcriptional activating protein and liver-enriched transcriptional inhibitory protein. Addition of cycloheximide blocked these increases and the downregulation of elastin mRNA by MG-132. The MG-132-induced downregulation of elastin transcription was dependent on C/EBPβ expression as assessed with small interfering RNA. These results indicate that the ubiquitin-proteasome pathway plays an essential role in maintaining elastin gene expression in lung fibroblasts. Disruption of this pathway results in the downregulation of tropoelastin transcription via posttranscriptionally induced C/EBPβ isoforms.
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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.
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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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Sanaei, Kaveh, Sydney Plotner, Anson Oommen Jacob, Jaime Ramirez-Vick, Narendra Vyavahare, and Nasim Nosoudi. "Effect of all-trans retinoic acid and pentagalloyl glucose on smooth muscle cell elastogenesis." Bio-Medical Materials and Engineering 32, no. 3 (May 18, 2021): 145–57. http://dx.doi.org/10.3233/bme-201152.
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BACKGROUND: The main objective of tissue engineering is to fabricate a tissue construct that mimics native tissue both biologically and mechanically. A recurring problem for tissue-engineered blood vessels (TEBV) is deficient elastogenesis from seeded smooth muscle cells. Elastin is an integral mechanical component in blood vessels, allowing elastic deformation and retraction in response to the shear and pulsatile forces of the cardiac system. OBJECTIVE: The goal of this research is to assess the effect of the vitamin A derivative all-trans retinoic acid (RA) and polyphenol pentagalloyl glucose (PGG) on the expression of elastin in human aortic smooth muscle cells (hASMC). METHODS: A polycaprolactone (PCL) and the gelatin polymer composite was electrospun and doped with RA and PGG. The scaffolds were subsequently seeded with hASMCs and incubated for five weeks. The resulting tissue-engineered constructs were evaluated using qPCR and Fastin assay for their elastin expression and deposition. RESULTS: All treatments showed an increased elastin expression compared to the control, with PGG treatments showing a significant increase in gene expression and elastin deposition.
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Joyce, Belinda J., Megan J. Wallace, Richard A. Pierce, Richard Harding, and Stuart B. Hooper. "Sustained changes in lung expansion alter tropoelastin mRNA levels and elastin content in fetal sheep lungs." American Journal of Physiology-Lung Cellular and Molecular Physiology 284, no. 4 (April 1, 2003): L643—L649. http://dx.doi.org/10.1152/ajplung.00090.2002.
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Our objective was to determine the effects of sustained alterations in fetal lung expansion on pulmonary elastin synthesis. In fetal sheep, lung expansion was either decreased between 111 and 131 days' gestation (term ∼147 days) by tracheal drainage or increased for 2, 4, 7, or 10 days by tracheal obstruction, ending at 128 days' gestation. Lung tropoelastin mRNA levels were assessed by Northern blot analysis, total elastin content was measured biochemically, and staining of lung sections was used to assess the localization and form of elastic fibers. Tracheal obstruction significantly elevated pulmonary tropoelastin mRNA levels 2.5-fold at 2 days, but values were not different from controls at 4, 7, and 10 days; elastin content tended to be increased at all time points. A sustained decrease in lung expansion by tracheal drainage reduced pulmonary tropoelastin mRNA levels 2.5-fold; elastin content was also decreased compared with controls, and tissue localization was altered. Our results indicate that the degree of lung expansion in the fetus influences elastin synthesis, content, and tissue deposition.
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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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Misra, Ashish, Abdul Q. Sheikh, Abhishek Kumar, Jiesi Luo, Jiasheng Zhang, Robert B. Hinton, Leslie Smoot, et al. "Integrin β3 inhibition is a therapeutic strategy for supravalvular aortic stenosis." Journal of Experimental Medicine 213, no. 3 (February 8, 2016): 451–63. http://dx.doi.org/10.1084/jem.20150688.
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The aorta is the largest artery in the body, yet processes underlying aortic pathology are poorly understood. The arterial media consists of circumferential layers of elastic lamellae and smooth muscle cells (SMCs), and many arterial diseases are characterized by defective lamellae and excess SMCs; however, a mechanism linking these pathological features is lacking. In this study, we use lineage and genetic analysis, pharmacological inhibition, explant cultures, and induced pluripotent stem cells (iPSCs) to investigate supravalvular aortic stenosis (SVAS) patients and/or elastin mutant mice that model SVAS. These experiments demonstrate that multiple preexisting SMCs give rise to excess aortic SMCs in elastin mutants, and these SMCs are hyperproliferative and dedifferentiated. In addition, SVAS iPSC-derived SMCs and the aortic media of elastin mutant mice and SVAS patients have enhanced integrin β3 levels, activation, and downstream signaling, resulting in SMC misalignment and hyperproliferation. Reduced β3 gene dosage in elastin-null mice mitigates pathological aortic muscularization, SMC misorientation, and lumen loss and extends survival, which is unprecedented. Finally, pharmacological β3 inhibition in elastin mutant mice and explants attenuates aortic hypermuscularization and stenosis. Thus, integrin β3–mediated signaling in SMCs links elastin deficiency and pathological stenosis, and inhibiting this pathway is an attractive therapeutic strategy for SVAS.