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Sample records for iii collagen iiinys

  1. Propolis Modifies Collagen Types I and III Accumulation in the Matrix of Burnt Tissue

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    Pawel Olczyk

    2013-01-01

    Full Text Available Wound healing represents an interactive process which requires highly organized activity of various cells, synthesizing cytokines, growth factors, and collagen. Collagen types I and III, serving as structural and regulatory molecules, play pivotal roles during wound healing. The aim of this study was to compare the propolis and silver sulfadiazine therapeutic efficacy throughout the quantitative and qualitative assessment of collagen types I and III accumulation in the matrix of burnt tissues. Burn wounds were inflicted on pigs, chosen for the evaluation of wound repair because of many similarities between pig and human skin. Isolated collagen types I and III were estimated by the surface plasmon resonance method with a subsequent collagenous quantification using electrophoretic and densitometric analyses. Propolis burn treatment led to enhanced collagens and its components expression, especially during the initial stage of the study. Less expressed changes were observed after silver sulfadiazine (AgSD application. AgSD and, with a smaller intensity, propolis stimulated accumulation of collagenous degradation products. The assessed propolis therapeutic efficacy, throughout quantitatively and qualitatively analyses of collagen types I and III expression and degradation in wounds matrix, may indicate that apitherapeutic agent can generate favorable biochemical environment supporting reepithelization.

  2. The content and ratio of type I and III collagen in skin differ with age ...

    African Journals Online (AJOL)

    III ratio and changes in skin tension, elasticity, and healing. Also, the content of type I, III collagen and type I/III ratio are significantly altered in hypertrophic scar tissue compared to uninjured age-matched controls, resulting in a different structural ...

  3. Second harmonic generation microscopy differentiates collagen type I and type III in COPD

    Science.gov (United States)

    Suzuki, Masaru; Kayra, Damian; Elliott, W. Mark; Hogg, James C.; Abraham, Thomas

    2012-03-01

    The structural remodeling of extracellular matrix proteins in peripheral lung region is an important feature in chronic obstructive pulmonary disease (COPD). Multiphoton microscopy is capable of inducing specific second harmonic generation (SHG) signal from non-centrosymmetric structural proteins such as fibrillar collagens. In this study, SHG microscopy was used to examine structural remodeling of the fibrillar collagens in human lungs undergoing emphysematous destruction (n=2). The SHG signals originating from these diseased lung thin sections from base to apex (n=16) were captured simultaneously in both forward and backward directions. We found that the SHG images detected in the forward direction showed well-developed and well-structured thick collagen fibers while the SHG images detected in the backward direction showed striking different morphological features which included the diffused pattern of forward detected structures plus other forms of collagen structures. Comparison of these images with the wellestablished immunohistochemical staining indicated that the structures detected in the forward direction are primarily the thick collagen type I fibers and the structures identified in the backward direction are diffusive structures of forward detected collagen type I plus collagen type III. In conclusion, we here demonstrate the feasibility of SHG microscopy in differentiating fibrillar collagen subtypes and understanding their remodeling in diseased lung tissues.

  4. Binding of von Willebrand factor to collagen type III: role of specific amino acids in the collagen binding domain of vWF and effects of neighboring domains

    NARCIS (Netherlands)

    van der Plas, R. M.; Gomes, L.; Marquart, J. A.; Vink, T.; Meijers, J. C.; de Groot, P. G.; Sixma, J. J.; Huizinga, E. G.

    2000-01-01

    Binding of von Willebrand Factor (vWF) to sites of vascular injury is the first step of hemostasis. Collagen types I and III are important binding sites for vWF. We have previously determined the three-dimensional structure of the collagen binding A3 domain of vWF (Huizinga et al., Structure 1997;

  5. Myofibroblast Expression in Skin Wounds Is Enhanced by Collagen III Suppression

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    Mohammed M. Al-Qattan

    2015-01-01

    Full Text Available Generally speaking, the excessive expression of myofibroblasts is associated with excessive collagen production. One exception is seen in patients and animal models of Ehlers-Danlos syndrome type IV in which the COL3A1 gene mutation results in reduced collagen III but with concurrent increased myofibroblast expression. This paradox has not been examined with the use of external drugs/modalities to prevent hypertrophic scars. In this paper, we injected the rabbit ear wound model of hypertrophic scarring with two doses of a protein called nAG, which is known to reduce collagen expression and to suppress hypertrophic scarring in that animal model. The higher nAG dose was associated with significantly less collagen III expression and concurrent higher degree of myofibroblast expression. We concluded that collagen III content of the extracellular matrix may have a direct or an indirect effect on myofibroblast differentiation. However, further research is required to investigate the pathogenesis of this paradoxical phenomenon.

  6. The extracellular matrix of Gadus morhua muscle contains types III, V, VI and IV collagens in addition to type I

    DEFF Research Database (Denmark)

    Brüggemann, Dagmar Adeline; Lawson, M.A.

    2005-01-01

    Confocal microscopy and immuno‐histochemistry were used to examine collagens in the extracellular matrix of cod Gadus morhua swimming muscle. In addition to the well known presence of type I fibrous collagen, types III and VI were also found in the myocommata and the endomysium. The beaded collagen......, type VI, was found in the endomysium and the network forming collagen, type IV, was found in the basement membrane. This is the first report of type V collagen in cod muscle and of types II, IV and VI in the muscle of a teleost....

  7. Collagen Type III Metabolism Evaluation in Patients with Malignant Head and Neck Cancer Treated with Radiotherapy

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    Klaudia Mazurek

    2018-01-01

    Full Text Available Ionizing radiation affects the metabolism of key proteins of extracellular matrix including type III collagen, an important component of human skin. The aim of the work is an analysis of the impact of radical and palliative radiotherapy on collagen type III synthesis in patients with head and neck cancer. The test group consisted of 56 males with histopathologically confirmed head and neck cancer, for whom radiotherapy was applied as a form of radical or palliative treatment. The level of procollagen III aminoterminal propeptide (PIIINP, which is a marker of collagen type III synthesis, was determined in blood serum before radiotherapy, immediately following radiotherapy, and 3 months after it was finished. As a result of radical radiotherapy a statistically significant decrease of PIIINP levels in serum (p<0.0001 was observed, both immediately after the radiotherapy and 3 months after the end of the treatment. Also the palliative radiotherapy caused a significant decrease of PIIINP right after the treatment (p=0.0052, as well as during the examination performed 3 months later (p=0.0004. The achieved results suggest that PIIINP can be used as a marker helpful in assessing radiation damage to connective tissue.

  8. Changes in histoanatomical distribution of types I, III and V collagen promote adaptative remodeling in posterior tibial tendon rupture

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    Érika Satomi

    2008-01-01

    Full Text Available INTRODUCTION: Posterior tibial tendon dysfunction is a common cause of adult flat foot deformity, and its etiology is unknown. PURPOSE: In this study, we characterized the morphologic pattern and distribution of types I, III and V collagen in posterior tibial tendon dysfunction. METHOD: Tendon samples from patients with and without posterior tibial tendon dysfunction were stained by immunofluorescence using antibodies against types I, III and V collagen. RESULTS: Control samples showed that type V deposited near the vessels only, while surgically obtained specimens displayed type V collagen surrounding other types of collagen fibers in thicker adventitial layers. Type III collagen levels were also increased in pathological specimens. On the other hand, amounts of collagen type I, which represents 95% of the total collagen amount in normal tendon, were decreased in pathological specimens. CONCLUSION: Fibrillogenesis in posterior tibial tendon dysfunction is altered due to higher expression of types III and V collagen and a decreased amount of collagen type I, which renders the originating fibrils structurally less resistant to mechanical forces.

  9. The structural and optical properties of type III human collagen biosynthetic corneal substitutes

    Science.gov (United States)

    Hayes, Sally; Lewis, Phillip; Islam, M. Mirazul; Doutch, James; Sorensen, Thomas; White, Tomas; Griffith, May; Meek, Keith M.

    2015-01-01

    The structural and optical properties of clinically biocompatible, cell-free hydrogels comprised of synthetically cross-linked and moulded recombinant human collagen type III (RHCIII) with and without the incorporation of 2-methacryloyloxyethyl phosphorylcholine (MPC) were assessed using transmission electron microscopy (TEM), X-ray scattering, spectroscopy and refractometry. These findings were examined alongside similarly obtained data from 21 human donor corneas. TEM demonstrated the presence of loosely bundled aggregates of fine collagen filaments within both RHCIII and RHCIII-MPC implants, which X-ray scattering showed to lack D-banding and be preferentially aligned in a uniaxial orientation throughout. This arrangement differs from the predominantly biaxial alignment of collagen fibrils that exists in the human cornea. By virtue of their high water content (90%), very fine collagen filaments (2–9 nm) and lack of cells, the collagen hydrogels were found to transmit almost all incident light in the visible spectrum. They also transmitted a large proportion of UV light compared to the cornea which acts as an effective UV filter. Patients implanted with these hydrogels should be cautious about UV exposure prior to regrowth of the epithelium and in-growth of corneal cells into the implants. PMID:26159106

  10. Collagen Type III and VI Turnover in Response to Long-Term Immobilization.

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    Shu Sun

    Full Text Available Muscle mass and function are perturbed by immobilization and remobilization. When muscle mass changes, the quality and quantity of the extracellular matrix protein, particularly the collagens, change with it. In this study, we investigated the temporal profile of three peptide biomarkers derived from turnover of collagen type III and type VI in a long-term immobilization and remobilization study. We also compared individual biomarker levels with Lean body Mass (LBM and changes therein, hypothesizing that these biomarkers would be biomarkers of the remodeling processes associated with immobilization and/or remobilization.In the Berlin bed rest study, 20 young men were recruited and randomly assigned to 8-week's strict bed rest with or without resistive vibration exercise countermeasure. We measured three neo-epitope ELISA kits in the serum samples of this study: Pro-C3, measured the synthesis of collagen type III; Pro-C6, measured the synthesis of collagen type VI; and C6M measured the degradation of collagen type VI induced by MMP-2 and MMP-9 cleavage.Pro-C3 and Pro-C6 biomarkers are up-regulated with both immobilization and remobilization, whereas C6M is hardly affected at all. We found that Pro-C3 and C6M levels are related to LBM at baseline and that high levels of Pro-C6 are associated with smaller changes in muscle mass during both immobilization and remobilization.The Pro-C3 and-C6 biomarkers change likely reflect remodeling changes in response to unloading or reloading, whereas C6M does not appear to respond to unloading. Pro-C3 and C6M levels correlate with LBM at baseline, while Pro-C6 is related to the anabolic and catabolic responses to unloading and reloading.

  11. Evaluating adhesion reduction efficacy of type I/III collagen membrane and collagen-GAG resorbable matrix in primary flexor tendon repair in a chicken model.

    Science.gov (United States)

    Turner, John B; Corazzini, Rubina L; Butler, Timothy J; Garlick, David S; Rinker, Brian D

    2015-09-01

    Reduction of peritendinous adhesions after injury and repair has been the subject of extensive prior investigation. The application of a circumferential barrier at the repair site may limit the quantity of peritendinous adhesions while preserving the tendon's innate ability to heal. The authors compare the effectiveness of a type I/III collagen membrane and a collagen-glycosaminoglycan (GAG) resorbable matrix in reducing tendon adhesions in an experimental chicken model of a "zone II" tendon laceration and repair. In Leghorn chickens, flexor tendons were sharply divided using a scalpel and underwent repair in a standard fashion (54 total repairs). The sites were treated with a type I/III collagen membrane, collagen-GAG resorbable matrix, or saline in a randomized fashion. After 3 weeks, qualitative and semiquantitative histological analysis was performed to evaluate the "extent of peritendinous adhesions" and "nature of tendon healing." The data was evaluated with chi-square analysis and unpaired Student's t test. For both collagen materials, there was a statistically significant improvement in the degree of both extent of peritendinous adhesions and nature of tendon healing relative to the control group. There was no significant difference seen between the two materials. There was one tendon rupture observed in each treatment group. Surgical handling characteristics were subjectively favored for type I/III collagen membrane over the collagen-GAG resorbable matrix. The ideal method of reducing clinically significant tendon adhesions after injury remains elusive. Both materials in this study demonstrate promise in reducing tendon adhesions after flexor tendon repair without impeding tendon healing in this model.

  12. Matrix metalloproteinase-9-mediated type III collagen degradation as a novel serological biochemical marker for liver fibrogenesis

    DEFF Research Database (Denmark)

    Veidal, Sanne S; Vassiliadis, Efstathios; Barascuk, Natasha

    2010-01-01

    During fibrogenesis in the liver, in which excessive remodelling of the extracellular matrix (ECM) occurs, both the quantity of type III collagen (CO3) and levels of matrix metalloproteinases (MMPs), including MMP-9, increase significantly. MMPs play major roles in ECM remodelling, via...... their activity in the proteolytic degradation of extracellular macromolecules such as collagens, resulting in the generation of specific cleavage fragments. These neo-epitopes may be used as markers of fibrosis....

  13. Influence of Term of Exposure to High-Fat Diet-Induced Obesity on Myocardial Collagen Type I and III

    International Nuclear Information System (INIS)

    Silva, Danielle Cristina Tomaz da; Lima-Leopoldo, Ana Paula; Leopoldo, André Soares; Campos, Dijon Henrique Salomé de; Nascimento, André Ferreira do; Oliveira, Sílvio Assis Junior de; Padovani, Carlos Roberto; Cicogna, Antonio Carlos

    2014-01-01

    Obesity is a risk factor for many medical complications; medical research has shown that hemodynamic, morphological and functional abnormalities are correlated with the duration and severity of obesity. Present study determined the influence of term of exposure to high-fat diet-induced obesity on myocardial collagen type I and III. Thirty-day-old male Wistar rats were randomly distributed into two groups: a control (C) group fed a standard rat chow and an obese (Ob) group alternately fed one of four palatable high-fat diets. Each diet was changed daily, and the rats were maintained on their respective diets for 15 (C 15 and Ob 15 ) and 30 (C 30 and Ob 30 ) consecutive weeks. Obesity was determined by adiposity index. The Ob 15 group was similar to the C 15 group regarding the expression of myocardial collagen type I; however, expression in the Ob 30 group was less than C 30 group. The time of exposure to obesity was associated with a reduction in collagen type I in Ob 30 when compared with Ob 15 . Obesity did not affect collagen type III expression. This study showed that the time of exposure to obesity for 30 weeks induced by unsaturated high-fat diet caused a reduction in myocardial collagen type I expression in the obese rats. However, no effect was seen on myocardial collagen type III expression

  14. Influence of Term of Exposure to High-Fat Diet-Induced Obesity on Myocardial Collagen Type I and III

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    Silva, Danielle Cristina Tomaz da [Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista (UNESP), Botucatu, SP (Brazil); Lima-Leopoldo, Ana Paula; Leopoldo, André Soares [Departamento de Esportes, Centro de Educação Física e Desportos da Universidade Federal do Espírito Santo (UFES), Vitória, ES (Brazil); Campos, Dijon Henrique Salomé de; Nascimento, André Ferreira do [Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista (UNESP), Botucatu, SP (Brazil); Oliveira, Sílvio Assis Junior de [Escola de Fisioterapia da Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil); Padovani, Carlos Roberto [Departamento de Bioestatística do Instituto de Ciências Biológicas da Universidade Estadual Paulista (UNESP), Botucatu, SP (Brazil); Cicogna, Antonio Carlos, E-mail: dany.tomaz@gmail.com [Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista (UNESP), Botucatu, SP (Brazil)

    2014-02-15

    Obesity is a risk factor for many medical complications; medical research has shown that hemodynamic, morphological and functional abnormalities are correlated with the duration and severity of obesity. Present study determined the influence of term of exposure to high-fat diet-induced obesity on myocardial collagen type I and III. Thirty-day-old male Wistar rats were randomly distributed into two groups: a control (C) group fed a standard rat chow and an obese (Ob) group alternately fed one of four palatable high-fat diets. Each diet was changed daily, and the rats were maintained on their respective diets for 15 (C{sub 15} and Ob{sub 15}) and 30 (C{sub 30} and Ob{sub 30}) consecutive weeks. Obesity was determined by adiposity index. The Ob{sub 15} group was similar to the C{sub 15} group regarding the expression of myocardial collagen type I; however, expression in the Ob{sub 30} group was less than C{sub 30} group. The time of exposure to obesity was associated with a reduction in collagen type I in Ob{sub 30} when compared with Ob{sub 15}. Obesity did not affect collagen type III expression. This study showed that the time of exposure to obesity for 30 weeks induced by unsaturated high-fat diet caused a reduction in myocardial collagen type I expression in the obese rats. However, no effect was seen on myocardial collagen type III expression.

  15. Collagen Type III Degradation Is Associated with Deterioration of Kidney Function in Patients with Type 2 Diabetes with Microalbuminuria

    DEFF Research Database (Denmark)

    Genovese, Federica; Hansen, Tine Wilum; Guldager, Daniel Kring Rasmussen

    Background In diabetes one of the main features of the progression to diabetic kidney disease is a pathological deposition of extracellular matrix components triggering renal fibrosis. The main structural component of the fibrotic core is collagen. One of the most prominent collagens is collagen...... type III (COL III), which is excessively synthesized and incorporated into the fibrotic extracellular matrix. Multiple studies in both humans and mice have suggested that MMP-9 activity is increased in diabetic kidney disease. We investigated whether a neo-epitope fragment of COL III generated by MMP-9...... (C3M) was associated with deterioration of kidney function in a well-characterised type 2 diabetic population with microalbuminuria and without symptoms of coronary artery disease. Methods The cohort included 200 participants, followed for 6.1 years. We measured C3M levels in serum (S-C3M) and urine...

  16. Matrix metalloproteinase-9-mediated type III collagen degradation as a novel serological biochemical marker for liver fibrogenesis

    DEFF Research Database (Denmark)

    Veidal, Sanne S; Vassiliadis, Efstathios; Barascuk, Natasha

    2010-01-01

    During fibrogenesis in the liver, in which excessive remodelling of the extracellular matrix (ECM) occurs, both the quantity of type III collagen (CO3) and levels of matrix metalloproteinases (MMPs), including MMP-9, increase significantly. MMPs play major roles in ECM remodelling, via...

  17. Circulating CO3-610, a degradation product of collagen III, closely reflects liver collagen and portal pressure in rats with fibrosis

    Science.gov (United States)

    2011-01-01

    Background Hepatic fibrosis is characterized by intense tissue remodeling, mainly driven by matrix metalloproteinases. We previously identified CO3-610, a type III collagen neoepitope generated by matrix metalloproteinase (MMP)-9, and tested its performance as a fibrosis marker in rats with bile-duct ligation. In this study, we assessed whether CO3-610 could be used as a surrogate biomarker of liver fibrosis and portal hypertension in carbon tetrachloride-induced experimental fibrosis. Results For this study, 68 Wistar rats were used. Serum CO3-610 was measured by ELISA. Liver fibrosis was quantified by Sirius red staining. Serum hyaluronic acid (HA) was measured with a binding-protein assay. Gene expression of collagens I and III, Mmp2 and Mmp9, and tissue inhibitors of matrix metalloproteinase 1 (Timp1) and 2(Timp2) was quantified by PCR. Hemodynamic measurements were taken in a subgroup of animals. A close direct relationship was found between serum CO3-610 and hepatic collagen content (r = 0.78; P fibrosis (43.5 ± 3.3 ng/mL, P Liver Mmp9 expression increased significantly in fibrotic animals but decreased to control levels in cirrhotic ones. Conclusions Circulating CO3-610 behaves as a reliable indicator of hepatic remodeling and portal hypertension in experimental fibrosis. This peptide could ultimately be a useful marker for the management of liver disease in patients. PMID:21813019

  18. Effects of solid acellular type-I/III collagen biomaterials on in vitro and in vivo chondrogenesis of mesenchymal stem cells.

    Science.gov (United States)

    Gao, Liang; Orth, Patrick; Cucchiarini, Magali; Madry, Henning

    2017-09-01

    Type-I/III collagen membranes are advocated for clinical use in articular cartilage repair as being able of inducing chondrogenesis, a technique termed autologous matrix-induced chondrogenesis (AMIC). Area covered: The current in vitro and translational in vivo evidence for chondrogenic effects of solid acellular type-I/III collagen biomaterials. Expert commentary: In vitro, mesenchymal stem cells (MSCs) adhere to the fibers of the type-I/III collagen membrane. No in vitro study provides evidence that a type-I/III collagen matrix alone may induce chondrogenesis. Few in vitro studies compare the effects of type-I and type-II collagen scaffolds on chondrogenesis. Recent investigations suggest better chondrogenesis with type-II collagen scaffolds. A systematic review of the translational in vivo data identified one long-term study showing that covering of cartilage defects treated by microfracture with a type-I/III collagen membrane significantly enhanced the repair tissue volume compared with microfracture alone. Other in vivo evidence is lacking to suggest either improved histological structure or biomechanical function of the repair tissue. Taken together, there is a paucity of in vitro and preclinical in vivo evidence supporting the concept that solid acellular type-I/III collagen scaffolds may be superior to classical approaches to induce in vitro or in vivo chondrogenesis of MSCs.

  19. Crystal structure of the second fibronectin type III (FN3) domain from human collagen α1 type XX.

    Science.gov (United States)

    Zhao, Jingfeng; Ren, Jixia; Wang, Nan; Cheng, Zhong; Yang, Runmei; Lin, Gen; Guo, Yi; Cai, Dayong; Xie, Yong; Zhao, Xiaohong

    2017-12-01

    Collagen α1 type XX, which contains fibronectin type III (FN3) repeats involving six FN3 domains (referred to as the FN#1-FN#6 domains), is an unusual member of the fibril-associated collagens with interrupted triple helices (FACIT) subfamily of collagens. The results of standard protein BLAST suggest that the FN3 repeats might contribute to collagen α1 type XX acting as a cytokine receptor. To date, solution NMR structures of the FN#3, FN#4 and FN#6 domains have been determined. To obtain further structural evidence to understand the relationship between the structure and function of the FN3 repeats from collagen α1 type XX, the crystal structure of the FN#2 domain from human collagen α1 type XX (residues Pro386-Pro466; referred to as FN2-HCXX) was solved at 2.5 Å resolution. The crystal structure of FN2-HCXX shows an immunoglobulin-like fold containing a β-sandwich structure, which is formed by a three-stranded β-sheet (β1, β2 and β5) packed onto a four-stranded β-sheet (β3, β4, β6 and β7). Two consensus domains, tencon and fibcon, are structural analogues of FN2-HCXX. Fn8, an FN3 domain from human oncofoetal fibronectin, is the closest structural analogue of FN2-HCXX derived from a naturally occurring sequence. Based solely on the structural similarity of FN2-HCXX to other FN3 domains, the detailed functions of FN2-HCXX and the FN3 repeats in collagen α1 type XX cannot be identified.

  20. In situ hybridization reveals that type I and III collagens are produced by pericytes in the anterior pituitary gland of rats.

    Science.gov (United States)

    Fujiwara, Ken; Jindatip, Depicha; Kikuchi, Motoshi; Yashiro, Takashi

    2010-12-01

    Type I and III collagens widely occur in the rat anterior pituitary gland and are the main components of the extracellular matrix (ECM). Although ECM components possibly play an important role in the function of the anterior pituitary gland, little is known about collagen-producing cells. Type I collagen is a heterotrimer of two α1(I) chains (the product of the col1a1 gene) and one α2(I) chain (the product of the col1a2 gene). Type III collagen is a homotrimer of α1(III) chains (the product of the col3a1 gene). We used in situ hybridization with digoxigenin-labeled cRNA probes to examine the expression of col1a1, col1a2, and col3a1 mRNAs in the pituitary gland of adult rats. mRNA expression for these collagen genes was clearly observed, and cells expressing col1a1, col1a2, and col3a1 mRNA were located around capillaries in the gland. We also investigated the possible double-staining of collagen mRNA and pituitary hormones, S-100 protein (a marker of folliculo-stellate cells), or desmin (a marker of pericytes). Col1a1 and col3a1 mRNA were identified in desmin-immunopositive cells. Thus, only pericytes produce type I and III collagens in the rat anterior pituitary gland.

  1. Fe(III)-loaded collagen fiber as a heterogeneous catalyst for the photo-assisted decomposition of Malachite Green

    International Nuclear Information System (INIS)

    Liu Xiaohu; Tang Rui; He Qiang; Liao Xuepin; Shi Bi

    2010-01-01

    A heterogeneous catalyst for Fenton reaction was prepared by immobilizing Fe(III) onto collagen fiber and its catalytic activity for the photo-assisted decomposition of Malachite Green (MG) was investigated. The results indicated that this Fe(III)-immobilized collagen fiber (Fe-CF) can effectively catalyse the decoloration and decomposition/mineralization of MG in aqueous solution. Catalysed by Fe-CF, MG solution was completely decolorized in 30 min, while 55.0% of TOC was removed from the dye solution within 120 min in the presence of H 2 O 2 and UVA irradiation (365 nm, 10 W). Fe-CF was recycled for seven times with certain activity loss (32.6% in decoloration, 18.5% in TOC removal), and its catalytic activity can be easily recovered by re-immobilization of Fe(III). Therefore, Fe-CF could act as an efficient and cost-effective catalyst for the photo-assisted decomposition of MG, and shows potential applications in practice.

  2. Changes in the proportions of types I and III collagen in hemorrhoids: the sliding anal lining theory

    Directory of Open Access Journals (Sweden)

    Carlos Sardiñas

    2016-07-01

    Full Text Available Objective: This study aims to determine changes in the proportions of types I and III collagen in hemorrhoids and to verify the sliding anal canal lining theory. Patients and method: The study is focused on a sample of 17 patients, 9 females and 8 males (age range: 30–70 years, with grade III and grade IV hemorrhoids. Tissue from 4 fetuses (age: 16 weeks of gestation was used as control sample. All the participants gave their informed consent. Samples were gathered in 2014. All patients underwent open hemorrhoidectomy by using the technique described by Milligan and Morgan, published in Lancet journal in 1937. The hemorrhoid samples were stained with hematoxylin–eosin for the histologic study to confirm the hemorrhoidal tissue diagnosis. The picrosirius red staining protocol was used after the histologic analysis. The method used for image processing is described in the text. Images were imported to the Image Tool for Windows software. The same process was used on the embryonic tissue. Data resulting from the analysis of images were processed using STATISTICA, a software for statistical analysis. Results: When compared, it was found that the two tissues presented very different values, with hemorrhoids containing the highest type III collagen values. Conclusion: Our results seem to imply that hemorrhoids have a larger proportion of type III collagen than fetal tissue. They also suggest a possible age-related deterioration of the tissue. Resumo: Objetivo: Esse estudo tem por objetivo determinar mudanças nos percentuais do colágeno dos tipos I e III em hemorroidas e verificar a teoria do revestimento de canal anal deslizante. Pacientes e método: O estudo está focado em uma amostra de 17 pacientes (9 mulheres e 8 homes; faixa etária: 30-70 anos, com hemorroidas de graus III e IV. Utilizamos tecido de quatro fetos (idade: 16 semanas de gestação como amostra de controle. Todos os participantes deram consentimento informado. As amostras

  3. Radiation crosslinking of poly(butyl acrylate) during polymerization and grafted copolymerization with Cr(III) crosslinked collagen

    International Nuclear Information System (INIS)

    Pietrucha, K.; Kroh, J.

    1984-01-01

    Enhanced crosslinking of synthetic polymer simultaneous with grafting and homopolymerization processes have been observed in irradiated leather tanned with Cr(III) and embedded with aqueous emulsions of butyl acrylate. Extent of poly(butyl acrylate) crosslinking during copolymerization was found to be approximately one order higher than in the case of radiation polymerization of butyl acrylate in emulsion. New method for isolation of grafted copolymer based on degradation of collagen has been developed. The extent of crosslinking was calculated from the swelling data. (author)

  4. Radiation crosslinking of poly(butyl acrylate) during polymerization and grafted copolymerization with Cr(III) crosslinked collagen

    International Nuclear Information System (INIS)

    Pietrucha, K.; Kroh, J.

    1986-01-01

    Enhanced crosslinking of synthetic polymer simultaneously with grafting and homopolymerization processes has been observed in irradiated leather tanned with Cr(III) and embedded with aqueous emulsions of butyl acrylate. The extent of poly(butyl acrylate) crosslinking during copolymerization was found to be approximately one order higher than in the case of radiation polymerization of butyl acrylate in emulsion. A new method for isolation of grafted copolymer based on degradation of collagen has been developed. The extent of crosslinking was calculated from the swelling data. (author)

  5. Development and validation of an enzyme-linked immunosorbent assay for the quantification of a specific MMP-9 mediated degradation fragment of type III collagen--A novel biomarker of atherosclerotic plaque remodeling

    DEFF Research Database (Denmark)

    Barascuk, Natasha; Vassiliadis, Efstathios; Larsen, Lise

    2011-01-01

    Degradation of collagen in the arterial wall by matrix metalloproteinases is the hallmark of atherosclerosis. We have developed an ELISA for the quantification of type III collagen degradation mediated by MMP-9 in urine.......Degradation of collagen in the arterial wall by matrix metalloproteinases is the hallmark of atherosclerosis. We have developed an ELISA for the quantification of type III collagen degradation mediated by MMP-9 in urine....

  6. Nucleotide sequence of a cDNA coding for the amino-terminal region of human prepro. alpha. 1(III) collagen

    Energy Technology Data Exchange (ETDEWEB)

    Toman, P D; Ricca, G A [Rorer Biotechnology, Inc., Springfield, VA (USA); de Crombrugghe, B [National Institutes of Health, Bethesda, MD (USA)

    1988-07-25

    Type III Collagen is synthesized in a variety of tissues as a precursor macromolecule containing a leader sequence, a N-propeptide, a N-telopeptide, the triple helical region, a C-telopeptide, and C-propeptide. To further characterize the human type III collagen precursor, a human placental cDNA library was constructed in gt11 using an oligonucleotide derived from a partial cDNA sequence corresponding to the carboxy-terminal part of the 1(III) collagen. A cDNA was identified which contains the leader sequence, the N-propeptide and N-telopeptide regions. The DNA sequence of these regions are presented here. The triple helical, C-telopeptide and C-propeptide amino acid sequence for human type III collagen has been determined previously. A comparison of the human amino acid sequence with mouse, chicken, and calf sequence shows 81%, 81%, and 92% similarity, respectively. At the DNA level, the sequence similarity between human and mouse or chicken type III collagen sequences in this area is 82% and 77%, respectively.

  7. Incidence and specificity of antibodies to types I, II, III, IV, and V collagen in rheumatoid arthritis and other rheumatic diseases as measured by 125I-radioimmunoassay

    International Nuclear Information System (INIS)

    Stuart, J.M.; Huffstutter, E.H.; Townes, A.S.; Kang, A.H.

    1983-01-01

    Antibodies to human native and denatured types I, II, III, IV, and V collagens were measured using 125I-radioimmunoassay. Mean levels of binding by sera from 30 rheumatoid arthritis patients were significantly higher than those from 20 normal subjects against all of the collagens tested. The relative antibody concentration was higher in synovial fluid than in simultaneously obtained serum. Many patients with gout or various other rheumatic diseases also had detectable anticollagen antibodies. With a few notable exceptions, the majority of the reactivity detected in all patient groups was directed against covalent structural determinants present on all of the denatured collagens, suggesting a secondary reaction to tissue injury

  8. Human pro. cap alpha. 1(III) collagen: cDNA sequence for the 3' end

    Energy Technology Data Exchange (ETDEWEB)

    Mankoo, B S; Dalgleish, R

    1988-03-25

    The authors have previously isolated two overlapping cDNA clones, pIII-21 and pIII-33, which encode the C-terminal end of human type III procollagen. They now present the sequence of 2520 bases encoded in these cDNAs which overlaps other previously published sequences for the same gene. The sequence presented differs from previously published sequences at five positions.

  9. Myocardial repair with long-term and low-dose administration of a nitric oxide synthesis inhibitor. Myofibroblasts, type III collagen and fibronectin

    Directory of Open Access Journals (Sweden)

    Pessanha Mônica Gomes

    1999-01-01

    Full Text Available OBJECTIVE: To study the healing process of the myocardium in hypertensive rats undergoing inhibition of nitric oxide synthesis. METHODS: Two groups of animals were studied: one received L-NAME, 12mg/kg/day, and the other was a control group. The presence of type III collagen, fibronectin, and alpha-smooth muscle actin-positive cells was assessed by immunohistochemistry. RESULTS: Fibronectin was seen in both early and late lesions, while type III collagen was seen mainly in areas of incomplete healing, situated among myocytes and around the intramyocardial branches of the coronary arteries. Areas representing early and late lesions showed a population of spindle-shaped cells. Immunohistochemistry showed that these cells were positive for alpha-smooth muscle actin. CONCLUSION: In the myocardium of hypertensive rats, the alpha-smooth muscle actin-positive cells are related to the accumulation of type III collagen and fibronectin in the areas of myocardial damage.

  10. The neo-epitope specific PRO-C3 ELISA measures true formation of type III collagen associated with liver and muscle parameters

    DEFF Research Database (Denmark)

    Nielsen, Mette J; Nedergaard, Anders F; Sun, Shu

    2013-01-01

    AIM: The present study describes the assessment of true formation of type III collagen in different pathologies using a neo-epitope specific competitive Enzyme-linked immunosorbent assay (ELISA) towards the N-terminal propeptide of type III collagen (PRO-C3). METHODS: The monoclonal antibody...... was raised against the N-protease mediated cleavage site of the N-terminal propeptide of type III collagen and a competitive ELISA was developed using the selected antibody. The assay was evaluated in relation to neo-epitope specificity, technical performance, and as a marker for liver fibrosis and muscle...... mass using the rat carbon tetrachloride (CCl4) model and a study of immobilization induced muscle loss in humans, respectively. RESULTS: The ELISA was neo-epitope specific, technically stable and can be assessed in serum and plasma samples. In the CCl4 liver fibrosis model it was observed that serum...

  11. Chondrocyte-seeded type I/III collagen membrane for autologous chondrocyte transplantation

    DEFF Research Database (Denmark)

    Niemeyer, Philipp; Lenz, Philipp; Kreuz, Peter C

    2010-01-01

    PURPOSE: We report the 2-year clinical results and identify prognostic factors in patients treated with autologous chondrocyte transplantation by use of a collagen membrane to seed the chondrocytes (ACT-CS). METHODS: This is a prospective study of 59 patients who were treated with ACT......-CS represents a technical modification of membrane-associated autologous chondrocyte transplantation that combines easy handling and attractive application properties with reliable clinical results 24 months after surgery, especially in patients with isolated cartilage defects. Even though the failure rate...

  12. [Collagen nephritis].

    Science.gov (United States)

    Lago, N R; Bulos, M J; Monserrat, A J

    1997-01-01

    Fibrillar collagen in the glomeruli is considered specific of the nail-patella syndrome. A new nephropathy with diffuse intraglomerular deposition of type III collagen without nail and skeletal abnormalities has been described. We report the case of a 26-year-old woman who presented persistent proteinuria, hematuria, deafness without nail and skeletal abnormalities. The renal biopsy showed focal and segmental glomerulosclerosis by light microscopy. The electron microscopy revealed the presence of massive fibrillar collagen within the mesangial matriz and the basement membrane. This is the first patient reported in our country. We emphasize the usefulness of electron microscopy in the study of glomerular diseases.

  13. Collagen metabolism during wound healing in rats. The aminoterminal propeptide of type III procollagen in serum and wound fluid in relation to formation of granulation tissue

    DEFF Research Database (Denmark)

    Jensen, L T; Garbarsch, C; Hørslev-Petersen, K

    1993-01-01

    The aminoterminal propeptide of type III procollagen (PIIINP) in serum has been shown to correlate with fibrillogenesis, and thus to be a potential direct marker of type III collagen deposition. The aim of the study was to investigate the correlation between changes in serum PIIINP and formation ......, changes in serum PIIINP mirror fibrillogenesis. Furthermore, our study provides experimental evidence consistent with the hypothesis that wound fluid PIIINP directly mirrors the local formation of granulation tissue, independent of weight loss and cyclophosphamide treatment.......The aminoterminal propeptide of type III procollagen (PIIINP) in serum has been shown to correlate with fibrillogenesis, and thus to be a potential direct marker of type III collagen deposition. The aim of the study was to investigate the correlation between changes in serum PIIINP and formation...... loss caused by treatment, weight loss caused by starvation was investigated. In untreated rats, serum PIIINP and wound fluid PIIINP were related to formation of granulation tissue (serum: r = 0.58, p

  14. Location of 3-hydroxyproline residues in collagen types I, II, III, and V/XI implies a role in fibril supramolecular assembly.

    Science.gov (United States)

    Weis, Mary Ann; Hudson, David M; Kim, Lammy; Scott, Melissa; Wu, Jiann-Jiu; Eyre, David R

    2010-01-22

    Collagen triple helices are stabilized by 4-hydroxyproline residues. No function is known for the much less common 3-hydroxyproline (3Hyp), although genetic defects inhibiting its formation cause recessive osteogenesis imperfecta. To help understand the pathogenesis, we used mass spectrometry to identify the sites and local sequence motifs of 3Hyp residues in fibril-forming collagens from normal human and bovine tissues. The results confirm a single, essentially fully occupied 3Hyp site (A1) at Pro(986) in A-clade chains alpha1(I), alpha1(II), and alpha2(V). Two partially modified sites (A2 and A3) were found at Pro(944) in alpha1(II) and alpha2(V) and Pro(707) in alpha2(I) and alpha2(V), which differed from A1 in sequence motif. Significantly, the distance between sites 2 and 3, 237 residues, is close to the collagen D-period (234 residues). A search for additional D-periodic 3Hyp sites revealed a fourth site (A4) at Pro(470) in alpha2(V), 237 residues N-terminal to site 3. In contrast, human and bovine type III collagen contained no 3Hyp at any site, despite a candidate proline residue and recognizable A1 sequence motif. A conserved histidine in mammalian alpha1(III) at A1 may have prevented 3-hydroxylation because this site in chicken type III was fully hydroxylated, and tyrosine replaced histidine. All three B-clade type V/XI collagen chains revealed the same three sites of 3Hyp but at different loci and sequence contexts from those in A-clade collagen chains. Two of these B-clade sites were spaced apart by 231 residues. From these and other observations we propose a fundamental role for 3Hyp residues in the ordered self-assembly of collagen supramolecular structures.

  15. [Expressiona of c-Jun and collagens I and III in cultured human skin fibroblasts are affected by infrared ray radiation].

    Science.gov (United States)

    Liu, Ping; Yang, Rong-Li; Su, Hui; Li, Lin-Li; Song, Jian-Wen; Lu, Ning; Liu, Yu-Ze

    2016-02-01

    To observe the effect of solar infrared ray (IR) radiation on the expressions of c-Jun and collagens I and III in cultured human skin fibroblasts (HSFs) and explore the molecular mechanism by which IR radiation causes aging of the skin. Primarily cultured HSFs exposed to IR radiation were examined for changes of the cell viability with MTT assay. The mRNA and protein expressions of c-Jun and collagens I and III was detected with real-time quantitative PCR and immunocytochemistry. MTT assay showed that IR irradiation caused inhibition of cell proliferation compared with the control cells. The mRNA and protein expression of collagen I was decreased significantly by IR irradiation with the increase of the irradiation dose (Pradiation to initiate and promote skin photoaging.

  16. Increased Levels of Type I and III Collagen and Hyaluronan in Scleroderma Skin

    DEFF Research Database (Denmark)

    Søndergaard, Klaus; Heickendorff, Lene; L, Risteli

    1997-01-01

    The aminoterminal propeptide of type III procollagen (PIIINP) and the carboxyterminal propeptide of type I procollagen (PICP) and hyaluronan (HA) were measured in plasma and suction blister fluid from 13 systemic sclerosis patients and 11 healthy volunteers. Suction blisters and skin biopsies were...

  17. Effect of Topical Probiotic on MMP-13 and Collagen III Expression in the Dermis Layer of Male Rats Irradiated with Ultraviolet-B

    Directory of Open Access Journals (Sweden)

    Vita M. Tawaran

    2016-06-01

    Full Text Available Nowadays, there is a big interest in the use of topical probiotic preparations for skin health. One of the probiotics therurapeutic benefits is used as anti-aging. During aging, there is stimulation of activator protein-1 (AP-1 which is a transcription factor that inhibits the production of collagen and AP-1 supports the breakdown of collagen by enzymes called matrix metalloproteinases (MMPs. As administration of oral Lactobacillus plantarum could inhibit skin aging by lowering the activity of MMP, so the collagen degradation can be derived so probably topical use of Lactobacillus plantarum may give more prominent effects. We used 24 male rats Sprague-Dawley strain as research objects. This study was divided into two groups, the treatment and control groups. The shaved dorsal skin of rats were irradiated with UVB three times a week for 4 weeks with total irradiation dose of 840 mJ/cm2. Skin cream, containing 247.27x107 CFU non-replicating Lactobacillus plantarum FNCC 0020, was smeared on the treatment group, two times daily, whereas the control group did not receive any treatment. Skin biopsies were done at the end of the study for examination of MMP-13 and collagen III expressions. Intensity, distribution, and histoscore of MMP-13 between the treatment and the control group showed no significant difference (p>0.05. The treatment group showed a significant different in the intensity of collagen III with the density distribution of 20–50% and the highest density was 80% (p<0.01. Administration of topical cream L. plantarum FNCC 0020 increased the expression of collagen III density distribution, but not the MMP-13 expression.

  18. MMP-12 catalytic domain recognizes and cleaves at multiple sites in human skin collagen type I and type III

    DEFF Research Database (Denmark)

    Taddese, Samuel; Jung, Michael C; Ihling, Christian

    2010-01-01

    Collagens of either soft connective or mineralized tissues are subject to continuous remodeling and turnover. Undesired cleavage can be the result of an imbalance between proteases and their inhibitors. Owing to their superhelical structure, collagens are resistant to many proteases and matrix me...

  19. ABNORMAL TYPE-III COLLAGEN PRODUCED BY AN EXON-17-SKIPPING MUTATION OF THE COL3A1 GENE IN EHLERS-DANLOS SYNDROME TYPE-IV IS NOT INCORPORATED INTO THE EXTRACELLULAR-MATRIX

    NARCIS (Netherlands)

    CHIODO, AA; SILLENCE, DO; COLE, WG; BATEMAN, JF

    1995-01-01

    A novel heterozygous mutation of the COL3Al gene that encodes the alpha 1(III) chains of type III collagen was identified in a family with the: acrogeric form of Ehlers-Danlos syndrome type IV (EDS-IV). Cultured dermal fibroblasts produced normal and shortened alpha 1(III) chains. The triple helix

  20. Tissue elasticity displayed by elastography and its correlation with the characteristics of collagen type I and type III in prostatic stroma

    Directory of Open Access Journals (Sweden)

    Jie Tang

    2014-04-01

    Full Text Available We investigated the prostate elasticity displayed by elastography and its correlation with the content and distribution of collagen type I (Col1 and type III (Col3. A total of 62 patients underwent transrectal real-time tissue elastography (TRTE examinations. Targeted biopsies were performed after 12-core systematic biopsy. The tissues corresponding to the elastograms were stained with picric acid-sirius red. The distribution of Col1 and type Col3 was observed, and the collagen volume fraction (CVF of these two types of collagen fibers was calculated. The CVFs of Col1 in the stiff and soft groups were 0.05 ± 0.02 and 0.02 ± 0.01 (P = 0.002, respectively. The CVFs of Col3 in the stiff and soft groups were 0.05 ± 0.04 and 0.07 ± 0.03 (P = 0.13, respectively. The circular analysis results showed that collagen fibers were disorganized both in the soft and stiff groups. Col1 and Col3 were mainly cross-linked, and some parallelization was observed in the sections. The distributions of Col1 and Col3 were different between the stiff and soft groups (P = 0.03. In conclusion, the texture of the prostate is due to the content of Col1 and its relative correlation with Col3.

  1. Tissue elasticity displayed by elastography and its correlation with the characteristics of collagen type I and type III in prostatic stroma.

    Science.gov (United States)

    Tang, Jie; Zhang, Yan; Zhang, Ming-Bo; Li, Yan-Mi; Fei, Xiang; Song, Zhi-Gang

    2014-01-01

    We investigated the prostate elasticity displayed by elastography and its correlation with the content and distribution of collagen type I (Col1) and type III (Col3). A total of 62 patients underwent transrectal real-time tissue elastography (TRTE) examinations. Targeted biopsies were performed after 12-core systematic biopsy. The tissues corresponding to the elastograms were stained with picric acid-sirius red. The distribution of Col1 and type Col3 was observed, and the collagen volume fraction (CVF) of these two types of collagen fibers was calculated. The CVFs of Col1 in the stiff and soft groups were 0.05 ± 0.02 and 0.02 ± 0.01 (P = 0.002), respectively. The CVFs of Col3 in the stiff and soft groups were 0.05 ± 0.04 and 0.07 ± 0.03 (P = 0.13), respectively. The circular analysis results showed that collagen fibers were disorganized both in the soft and stiff groups. Col1 and Col3 were mainly cross-linked, and some parallelization was observed in the sections. The distributions of Col1 and Col3 were different between the stiff and soft groups (P = 0.03). In conclusion, the texture of the prostate is due to the content of Col1 and its relative correlation with Col3.

  2. New lethal disease involving type I and III collagen defect resembling geroderma osteodysplastica, De Barsy syndrome, and Ehlers-Danlos syndrome IV.

    Science.gov (United States)

    Jukkola, A; Kauppila, S; Risteli, L; Vuopala, K; Risteli, J; Leisti, J; Pajunen, L

    1998-06-01

    We describe the clinical findings and biochemical features of a male child suffering from a so far undescribed lethal connective tissue disorder characterised by extreme hypermobility of the joints, lax skin, cataracts, severe growth retardation, and insufficient production of type I and type III procollagens. His features are compared with Ehlers-Danlos type IV, De Barsy syndrome, and geroderma osteodysplastica, as these disorders show some symptoms and signs shared with our patient. The child died because of failure of the connective tissue structures joining the skull and the spine, leading to progressive spinal stenosis. The aortic valve was translucent and insufficient. The clinical symptoms and signs, together with histological findings, suggested a collagen defect. Studies on both skin fibroblast cultures and the patient's serum showed reduced synthesis of collagen types I and III at the protein and RNA levels. The sizes of the mRNAs and newly synthesised proteins were normal, excluding gross structural abnormalities. These findings are not in accordance with any other collagen defect characterised so far.

  3. Characterization of type I, II, III, IV, and V collagens by time-resolved laser-induced fluorescence spectroscopy

    Science.gov (United States)

    Marcu, Laura; Cohen, David; Maarek, Jean-Michel I.; Grundfest, Warren S.

    2000-04-01

    The relative proportions of genetically distinct collagen types in connective tissues vary with tissue type and change during disease progression, development, wound healing, aging. This study aims to 1) characterize the spectro- temporal fluorescence emission of fiber different types of collagen and 2) assess the ability of time-resolved laser- induced fluorescence spectroscopy to distinguish between collagen types. Fluorescence emission of commercially available purified samples was induced with nitrogen laser excitation pulses and detected with a MCP-PMT connected to a digital storage oscilloscope. The recorded time-resolved emission spectra displayed distinct fluorescence emission characteristics for each collagen type. The time domain information complemented the spectral domain intensity data for improved discrimination between different collagen types. Our results reveal that analysis of the fluorescence emission can be used to characterize different species of collagen. Also, the results suggest that time-resolved spectroscopy can be used for monitoring of connective tissue matrix composition changes due to various pathological and non-pathological conditions.

  4. Collagen turnover after tibial fractures

    DEFF Research Database (Denmark)

    Joerring, S; Krogsgaard, M; Wilbek, H

    1994-01-01

    Collagen turnover after tibial fractures was examined in 16 patients with fracture of the tibial diaphysis and in 8 patients with fracture in the tibial condyle area by measuring sequential changes in serological markers of turnover of types I and III collagen for up to 26 weeks after fracture....... The markers were the carboxy-terminal extension peptide of type I procollagen (PICP), the amino-terminal extension peptide of type III procollagen (PIIINP), and the pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (ICTP). The latter is a new serum marker of degradation of type I...... collagen. A group comparison showed characteristic sequential changes in the turnover of types I and III collagen in fractures of the tibial diaphysis and tibial condyles. The turnover of type III collagen reached a maximum after 2 weeks in both groups. The synthesis of type I collagen reached a maximum...

  5. [Intervention of pyrrolidine dithiocarbamate on expressions of connective tissue growth factor, type I collagen, and type III collage in acute paraquat poisoned rats].

    Science.gov (United States)

    Huang, Min; Yang, Hui-fang; Zhang, Ping; Chang, Xiu-li; Zhou, Zhi-jun

    2013-01-01

    To observe the changes in the expression of connective tissue growth factor (CTGF), type I collagen (Col I), and type III collagen (Col III) among the rats with acute paraquat (PQ) poisoning and the intervention effect of pyrrolidine dithiocarbamate (PDTC) on their expression, and to investigate the mechanism of PQ-induced pulmonary fibrosis and the intervention effect of PDTC on the disease. Sprague-Dawley rats were randomly divided into control group (n = 6), PQ group (n = 36), and PQ + PDTC group (n = 36). The PQ group and PQ + PDTC group were given a single dose of saline-diluted PQ (80 mg/kg) by gavage; 2 h later, the PQ + PDTC group was intraperitoneally injected with a single dose of PDTC (100 mg/kg), and the PQ group was intraperitoneally injected with the same amount of saline. The control group was given saline (1 ml/kg) by gavage and was intraperitoneally injected with the same amount of saline 2h later. At 1, 3, 7, 14, 25, and 56 days after operation, the protein expression of CTGF was evaluated by Western blot; the mRNA expression of CTGF, Col I, and Col III was analyzed by real-time quantitative PCR; the content of hydroxyproline in lung tissue was measured, and the pathological changes of lung tissue of the poisoned rats were observed. The protein expression of CTGF in the PQ group increased as the time went on, slowly from the 3rd to the 14th day and rapidly from the 28th to the 56th day, significantly higher than that in the control group at each time point (P < 0.05 or P < 0.01). The mRNA expression of CTGF in the PQ group began to rise markedly on the 1st day, increased rapidly from the 3rd to the 14th day, and remained at a relatively high level from the 28th to the 56th day, significantly higher than that in the control group at each time point (P < 0.01). The mRNA expression of Col I in the PQ group changed little on the 1st and 3rd day, increased slightly on the 7th day, and increased greatly from the 14th to the 56th day, significantly

  6. Hypoxia Is a Critical Parameter for Chondrogenic Differentiation of Human Umbilical Cord Blood Mesenchymal Stem Cells in Type I/III Collagen Sponges

    Directory of Open Access Journals (Sweden)

    Tangni Gómez-Leduc

    2017-09-01

    Full Text Available Umbilical cord blood (UCB is an attractive alternative to bone marrow for isolation of mesenchymal stem cells (MSCs to treat articular cartilage defects. Here, we set out to determine the growth factors (bone morphogenetic protein 2 (BMP-2 and transforming growth factor-β (TGF-β1 and oxygen tension effects during chondrogenesis of human UCB-MSCs for cartilage engineering. Chondrogenic differentiation was induced using 3D cultures in type I/III collagen sponges with chondrogenic factors in normoxia (21% O2 or hypoxia (<5% O2 for 7, 14 and 21 days. Our results show that UCB-MSCs can be committed to chondrogenesis in the presence of BMP-2+TGF-β1. Normoxia induced the highest levels of chondrocyte-specific markers. However, hypoxia exerted more benefit by decreasing collagen X and matrix metalloproteinase-13 (MMP13 expression, two chondrocyte hypertrophy markers. However, a better chondrogenesis was obtained by switching oxygen conditions, with seven days in normoxia followed by 14 days in hypoxia, since these conditions avoid hypertrophy of hUCB-MSC-derived chondrocytes while maintaining the expression of chondrocyte-specific markers observed in normoxia. Our study demonstrates that oxygen tension is a key factor for chondrogenesis and suggests that UBC-MSCs 3D-culture should begin in normoxia to obtain a more efficient chondrocyte differentiation before placing them in hypoxia for chondrocyte phenotype stabilization. UCB-MSCs are therefore a reliable source for cartilage engineering.

  7. In vitro colonization of the muscle extracellular matrix components by Escherichia coli O157:H7: the influence of growth medium, temperature and pH on initial adhesion and induction of biofilm formation by collagens I and III.

    Directory of Open Access Journals (Sweden)

    Caroline Chagnot

    Full Text Available Enterohemorrhagic Escherichia coli (EHEC O157:H7 are responsible for repeated food-poisoning cases often caused by contaminated burgers. EHEC infection is predominantly a pediatric illness, which can lead to life-threatening diseases. Ruminants are the main natural reservoir for EHEC and food contamination almost always originates from faecal contamination. In beef meat products, primary bacterial contamination occurs at the dehiding stage of slaughtering. The extracellular matrix (ECM is the most exposed part of the skeletal muscles in beef carcasses. Investigating the adhesion to the main muscle fibrous ECM proteins, insoluble fibronectin, collagen I, III and IV, laminin-α2 and elastin, results demonstrated that the preceding growth conditions had a great influence on subsequent bacterial attachment. In the tested experimental conditions, maximal adhesion to fibril-forming collagens I or III occurred at 25°C and pH 7. Once initially adhered, exposure to lower temperatures, as applied to meat during cutting and storage, or acidification, as in the course of post-mortem physiological modifications of muscle, had no effect on detachment, except at pHu. In addition, dense biofilm formation occurred on immobilized collagen I or III and was induced in growth medium supplemented with collagen I in solution. From this first comprehensive investigation of EHEC adhesion to ECM proteins with respect to muscle biology and meat processing, new research directions for the development of innovative practices to minimize the risk of meat contamination are further discussed.

  8. A multicenter, double-blind, randomized, controlled phase III clinical trial of chicken type II collagen in rheumatoid arthritis.

    Science.gov (United States)

    Wei, Wei; Zhang, Ling-Ling; Xu, Jian-Hua; Xiao, Feng; Bao, Chun-De; Ni, Li-Qing; Li, Xing-Fu; Wu, Yu-Qing; Sun, Ling-Yun; Zhang, Rong-Hua; Sun, Bao-Liang; Xu, Sheng-Qian; Liu, Shang; Zhang, Wei; Shen, Jie; Liu, Hua-Xiang; Wang, Ren-Cheng

    2009-01-01

    Chicken type II collagen (CCII) is a protein extracted from the cartilage of chicken breast and exhibits intriguing possibilities for the treatment of autoimmune diseases by inducing oral tolerance. A 24-week, double-blind, double-dummy, randomized, methotrexate (MTX)-controlled study was conducted to evaluate the efficacy and safety of CCII in the treatment of rheumatoid arthritis (RA). Five hundred three RA patients were included in the study. Patients received either 0.1 mg daily of CCII (n = 326) or 10 mg once a week of MTX (n = 177) for 24 weeks. Each patient was evaluated for pain, morning stiffness, tender joint count, swollen joint count, health assessment questionnaire (HAQ), assessments by investigator and patient, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) by using the standard tools at baseline (week 0) and at weeks 12 and 24. Additionally, rheumatoid factor (RF) was evaluated at weeks 0 and 24. Measurement of a battery of biochemical parameters in serum, hematological parameters, and urine analysis was performed to evaluate the safety of CCII. Four hundred fifty-four patients (94.43%) completed the 24-week follow-up. In both groups, there were decreases in pain, morning stiffness, tender joint count, swollen joint count, HAQ, and assessments by investigator and patient, and all differences were statistically significant. In the MTX group, ESR and CRP decreased. RF did not change in either group. At 24 weeks, 41.55% of patients in the CCII group and 57.86% in the MTX group met the American College of Rheumatology 20% improvement criteria (ACR-20) and 16.89% and 30.82%, respectively, met the ACR 50% improvement criteria (ACR-50). Both response rates for ACR-20 and ACR-50 in the CCII group were lower than those of the MTX group, and this difference was statistically significant (P < 0.05). The DAS28 (disease activity score using 28 joint counts) values of the two treatment groups were calculated, and there was a statistically

  9. Tissue turnover of collagen type I, III and elastin is elevated in the PCLS model of IPF and can be restored back to vehicle levels using a phosphodiesterase inhibitor

    DEFF Research Database (Denmark)

    Hansen, Niels Ulrik Brandt; Karsdal, Morten Asser; Brockbank, Sarah

    2016-01-01

    .T., two days apart. The rats were euthanized fourteen days after the last dose. PCLS were made and cultured for 48 h in: medium, medium + 100 μM IBMX (PDE inhibitor), or medium + 10 μM GM6001 (MMP inhibitor). Turnover of type I collagen (P1NP, C1M), type III collagen (iP3NP, C3M) and elastin degradation...... to the culture medium (P ≤ 0.05 - P ≤ 0.0001). Sirius Red and Orcein staining confirmed the presence of collagen and elastin deposition in the lungs of the animals receiving BLM. Conclusions: The protein fingerprint technology allows the assessment of ECM remodeling markers in the BLM PCLS model. By combining...

  10. Linkage mapping of the gene for Type III collagen (COL3A1) to human chromosome 2q using a VNTR polymorphism

    Energy Technology Data Exchange (ETDEWEB)

    Tiller, G.E.; Polumbo, P.A.; Summar, M.L. (Vanderbilt Univ. Medical Center, Nashville, TN (United States))

    1994-03-15

    The gene for the [alpha]1(III) chain of type III collagen, COL3A1, has been previously mapped to human chromosome 2q24.3-q31 by in situ hybridization. Physical mapping by pulsed-field gel electrophoresis has demonstrated that COL3A1 lies within 35 kb of COL5A2. The authors genotyped the CEPH families at the COL3A2 locus using a pentanucleotide repeat polymorphism within intron 25. They demonstrated significant linkage to 18 anonymous markers as well as the gene for carbamyl phosphate synthetase (CPSI), which had been previously mapped to this region. No recombination was seen between COL3A1 and COL5A2 (Z = 9.93 at [theta] = 0) or D2S24 (Z = 10.55 at [theta] = 0). The locus order is (D2S32-D2S138-D2S148)-(D2S24-COL5A2-COL3A1)-(D2S118-D2S161), with odds of 1:2300 for the next most likely order. These relationships are consistent with the physical mapping of COL3A1 to the distal portion of 2q and place it proximal to CPSI by means of multipoint analysis. These linkage relationships should prove useful in further studies of Ehlers-Danlos syndrome type IV and carbamyl phosphate synthetase I deficiency and provide an additional framework for localizing other genes in this region. 13 refs., 2 figs., 1 tab.

  11. Viability of chondrocytes seeded onto a collagen I/III membrane for matrix-induced autologous chondrocyte implantation.

    Science.gov (United States)

    Hindle, Paul; Hall, Andrew C; Biant, Leela C

    2014-11-01

    Cell viability is crucial for effective cell-based cartilage repair. The aim of this study was to determine the effect of handling the membrane during matrix-induced autologous chondrocyte implantation surgery on the viability of implanted chondrocytes. Images were acquired under five conditions: (i) Pre-operative; (ii) Handled during surgery; (iii) Cut edge; (iv) Thumb pressure applied; (v) Heavily grasped with forceps. Live and dead cell stains were used. Images were obtained for cell counting and morphology. Mean cell density was 6.60 × 10(5) cells/cm(2) (5.74-7.11 × 10(5) ) in specimens that did not have significant trauma decreasing significantly in specimens that had been grasped with forceps (p < 0.001) or cut (p = 0.004). Cell viability on delivery grade membrane was 75.1%(72.4-77.8%). This dropped to 67.4%(64.1-69.7%) after handling (p = 0.002), 56.3%(51.5-61.6%) after being thumbed (p < 0.001) and 28.8%(24.7-31.2%) after crushing with forceps (p < 0.001). When cut with scissors there was a band of cell death approximately 275 µm in width where cell viability decreased to 13.7%(10.2-18.2%, p < 0.001). Higher magnification revealed cells without the typical rounded appearance of chondrocytes. We found that confocal laser-scanning microscope (CLSM) can be used to quantify and image the fine morphology of cells on a matrix-induced autologous chondrocyte implantation (MACI) membrane. Careful handling of the membrane is essential to minimise chondrocyte death during surgery. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  12. Biological alterations resulting from chronic lung irradiation. III. Effect of partial 60Co thoracic irradiation upon pulmonary collagen metabolism and fractionation in syrian hamsters

    International Nuclear Information System (INIS)

    Pickrell, J.A.; Harris, D.V.; Hahn, F.F.; Belasich, J.J.; Jones, R.K.

    1975-01-01

    Radiation-induced changes in pulmonary collagen metabolism were studied in Syrian hamsters given multiple thoracic doses of 60 Co radiation to achieve cumulative exposures of 6000, 4000, and 2000 R. At 13 to 14 wk after initial exposure, 6000- and 4000-R exposures had increased incorporation of injected [ 14 C]proline into pulmonary collagenous protein which suggested an increased collagen synthesis. By 21 to 22 wk after exposure, increased pulmonary soluble collagen was noted. Increased pulmonary scarring was indicated by a variable increase in native collagen at 13 to 36 wk. A collection of alveolar macrophages at 7 to 8 wk followed by inflammation at 13 to 14 wk and a beginning of pulmonary fibrosis at 13 to 19 wk were noted. At 21 to 22 wk after exposure a somewhat more marked pulmonary fibrosis and some epithelialization were observed. Hemosiderin deposits were also observed at 35 to 36 wk after exposure, but pathologic processes were lessened by this time. The early activation of collagen synthesis presumably caused the radiation-induced fibrosis. Later, when collagen tended to accumulate, the synthetic rate was normal. The activation of collagen synthesis caused by external thoracic irradiation resembles that caused by thoracic irradiation from the internal emitter, 144 Ce. Moreover, it demonstrates the usefulness of monitoring collagen biosynthesis by [ 14 C]proline incorporation into the lung. (U.S.)

  13. Collagenous sprue

    DEFF Research Database (Denmark)

    Soendergaard, Christoffer; Riis, Lene Buhl; Nielsen, Ole Haagen

    2014-01-01

    Collagenous sprue is a rare clinicopathological condition of the small bowel. It is characterised by abnormal subepithelial collagen deposition and is typically associated with malabsorption, diarrhoea and weight loss. The clinical features of collagenous sprue often resemble those of coeliac...... disease and together with frequent histological findings like mucosal thinning and intraepithelial lymphocytosis the diagnosis may be hard to reach without awareness of this condition. While coeliac disease is treated using gluten restriction, collagenous sprue is, however, not improved...... by this intervention. In cases of diet-refractory 'coeliac disease' it is therefore essential to consider collagenous sprue to initiate treatment at an early stage to prevent the fibrotic progression. Here, we report a case of a 78-year-old man with collagenous sprue and present the clinical and histological...

  14. Changes in guinea-pig dermal collagen during development

    International Nuclear Information System (INIS)

    Shuttleworth, C.A.; Forrest, L.

    1975-01-01

    Guinea-pig dermis was digested with pepsin and the solubilized collagen molecules separated by differential salt precipitation at pH 7.5. Differences in subunit composition and amino acid analysis were noted between type I and type III collagen. Incorporation of radioactive proline into the developing foetus enabled isolation of labelled type I and type III collagens. Comparison of the specific activity of the isolated collagen molecules showed that type III collagen had a high specific activity in the early stages of foetal development, which decreased dramatically during foetal development. The specific activity of pepsin-solubilized type I collagen remained fairly constant during foetal development. (orig.) [de

  15. Collagen metabolism in obesity

    DEFF Research Database (Denmark)

    Rasmussen, M H; Jensen, L T; Andersen, T

    1995-01-01

    OBJECTIVE: To investigate the impact of obesity, fat distribution and weight loss on collagen turnover using serum concentrations of the carboxyterminal propeptide of type I procollagen (S-PICP) and the aminoterminal propeptide of type III pro-collagen (S-PIIINP) as markers for collagen turnover...... (r = 0.37; P = 0.004), height (r = 0.27; P = 0.04), waist circumference (r = 0.35; P = 0.007), as well as with WHR (r = 0.33; P = 0.01) and was inversely correlated to age (r = -0.40; P = 0.002). Compared with randomly selected controls from a large pool of healthy volunteers, the obese patients had...... restriction (P obesity and associated with body fat distribution, suggesting...

  16. Asiaticoside induces cell proliferation and collagen synthesis in human dermal fibroblasts

    Directory of Open Access Journals (Sweden)

    Linda Yuliati

    2015-12-01

    Asiaticoside induces HDF proliferation and type I and III collagen synthesis in a time- and dose-dependent pattern. Asiaticoside has a similar effect as retinoic acid on type I and type III collagen synthesis.

  17. A novel nano-structured porous polycaprolactone scaffold improves hyaline cartilage repair in a rabbit model compared to a collagen type I/III scaffold: in vitro and in vivo studies.

    Science.gov (United States)

    Christensen, Bjørn Borsøe; Foldager, Casper Bindzus; Hansen, Ole Møller; Kristiansen, Asger Albæk; Le, Dang Quang Svend; Nielsen, Agnete Desirée; Nygaard, Jens Vinge; Bünger, Cody Erik; Lind, Martin

    2012-06-01

    To develop a nano-structured porous polycaprolactone (NSP-PCL) scaffold and compare the articular cartilage repair potential with that of a commercially available collagen type I/III (Chondro-Gide) scaffold. By combining rapid prototyping and thermally induced phase separation, the NSP-PCL scaffold was produced for matrix-assisted autologous chondrocyte implantation. Lyophilizing a water-dioxane-PCL solution created micro and nano-pores. In vitro: The scaffolds were seeded with rabbit chondrocytes and cultured in hypoxia for 6 days. qRT-PCR was performed using primers for sox9, aggrecan, collagen type 1 and 2. In vivo: 15 New Zealand White Rabbits received bilateral osteochondral defects in the femoral intercondylar grooves. Autologous chondrocytes were harvested 4 weeks prior to surgery. There were 3 treatment groups: (1) NSP-PCL scaffold without cells. (2) The Chondro-Gide scaffold with autologous chondrocytes and (3) NSP-PCL scaffold with autologous chondrocytes. Observation period was 13 weeks. Histological evaluation was made using the O'Driscoll score. In vitro: The expressions of sox9 and aggrecan were higher in the NSP-PCL scaffold, while expression of collagen 1 was lower compared to the Chondro-Gide scaffold. In vivo: Both NSP-PCL scaffolds with and without cells scored significantly higher than the Chondro-Gide scaffold when looking at the structural integrity and the surface regularity of the repair tissue. No differences were found between the NSP-PCL scaffold with and without cells. The NSP-PCL scaffold demonstrated higher in vitro expression of chondrogenic markers and had higher in vivo histological scores compared to the Chondro-Gide scaffold. The improved chondrocytic differentiation can potentially produce more hyaline cartilage during clinical cartilage repair. It appears to be a suitable cell-free implant for hyaline cartilage repair and could provide a less costly and more effective treatment option than the Chondro-Gide scaffold with cells.

  18. Collagen derived serum markers in carcinoma of the prostate

    DEFF Research Database (Denmark)

    Rudnicki, M; Jensen, L T; Iversen, P

    1995-01-01

    Three new collagen markers deriving from the collagenous matrix, e.g. carboxyterminal propeptide of type I procollagen (PICP), carboxy-terminal pyridinoline cross-linked telopeptide of type I collagen (ICTP), and aminoterminal propeptide of type III procollagen (PIIINP) were used for the diagnose...

  19. Study of collagen metabolism after β radiation injury

    International Nuclear Information System (INIS)

    Zhou Yinghui; Xulan; Wu Shiliang; Zhang Xueguang; Chen Liesong

    2000-01-01

    Objective: To investigate the change of collagen metabolism and it's regulation after β radiation. Method: The animal model of β radiation injury was established by the β radiation produced by the linear accelerator; and irradiated NIH 3T3 cells were studied. In the experiment the contents of total collagen, collagen type I and type III were measured. The activity of MMPs-1 was tested. The contents of TGF-β 1 , IL-6 were also detected. Results: After exposure to β radiation, little change was found in the content of total collagen, but the content of collagen I decreased and the content of collagen III, MMPs-1 activity increased; the expression of TGF-β 1 , IL-6 increased. Conclusion: The changes in the metabolism of collagen play an important role in the irradiated injury of the skin; TGF-β 1 and IL-6 may be essential in the regulation of the collagen metabolism

  20. New lethal disease involving type I and III collagen defect resembling geroderma osteodysplastica, De Barsy syndrome, and Ehlers-Danlos syndrome IV.

    OpenAIRE

    Jukkola, A; Kauppila, S; Risteli, L; Vuopala, K; Risteli, J; Leisti, J; Pajunen, L

    1998-01-01

    We describe the clinical findings and biochemical features of a male child suffering from a so far undescribed lethal connective tissue disorder characterised by extreme hypermobility of the joints, lax skin, cataracts, severe growth retardation, and insufficient production of type I and type III procollagens. His features are compared with Ehlers-Danlos type IV, De Barsy syndrome, and geroderma osteodysplastica, as these disorders show some symptoms and signs shared with our patient. The chi...

  1. Study of collagen metabolism and regulation after β radiation injury

    International Nuclear Information System (INIS)

    Zhou Yinghui; Xu Lan; Wu Shiliang; Qiu Hao; Jiang Zhi; Tu Youbin; Zhang Xueguang

    2001-01-01

    The animal model of β radiation injury was established by the β radiation produced by the linear accelerator; and irradiated NIH 3T3 cells were studied. In the experiment the contents of total collagen, collagen type I and type III were measured. The activity of MMPs-1 were tested. The contents of TGF-β 1 , IL-6 were also detected. The results showed that after exposure to β radiation, little change was found in the content of total collagen, but the content of collagen I decreased and the content of collagen III, MMPs-1 activity increased; the expression of TGF-β 1 , IL-6 increased. The results suggest that changes in the metabolism of collagen play an important role in the irradiated injury of the skin; TGF-β 1 , IL-6 may be essential in the regulation of the collagen metabolism

  2. Study of collagen metabolism and regulation after {beta} radiation injury

    Energy Technology Data Exchange (ETDEWEB)

    Yinghui, Zhou; Lan, Xu; Shiliang, Wu; Hao, Qiu; Zhi, Jiang; Youbin, Tu; Xueguang, Zhang [Suzhou Medical College (China)

    2001-04-01

    The animal model of {beta} radiation injury was established by the {beta} radiation produced by the linear accelerator; and irradiated NIH 3T3 cells were studied. In the experiment the contents of total collagen, collagen type I and type III were measured. The activity of MMPs-1 were tested. The contents of TGF-{beta}{sub 1}, IL-6 were also detected. The results showed that after exposure to {beta} radiation, little change was found in the content of total collagen, but the content of collagen I decreased and the content of collagen III, MMPs-1 activity increased; the expression of TGF-{beta}{sub 1}, IL-6 increased. The results suggest that changes in the metabolism of collagen play an important role in the irradiated injury of the skin; TGF-{beta}{sub 1}, IL-6 may be essential in the regulation of the collagen metabolism.

  3. Biological Differences between Hanwoo longissimus dorsi and semimembranosus Muscles in Collagen Synthesis of Fibroblasts.

    Science.gov (United States)

    Subramaniyan, Sivakumar Allur; Hwang, Inho

    2017-01-01

    Variations in physical toughness between muscles and animals are a function of growth rate and extend of collagen type I and III. The current study was designed to investigate the ability of growth rate, collagen concentration, collagen synthesizing and degrading genes on two different fibroblast cells derived from Hanwoo m. longissimus dorsi (LD) and semimembranosus (SM) muscles. Fibroblast cell survival time was determined for understanding about the characteristics of proliferation rate between the two fibroblasts. We examined the collagen concentration and protein expression of collagen type I and III between the two fibroblasts. The mRNA expression of collagen synthesis and collagen degrading genes to elucidate the molecular mechanisms on toughness and tenderness through collagen production between the two fibroblast cells. From our results the growth rate, collagen content and protein expression of collagen type I and III were significantly higher in SM than LD muscle fibroblast. The mRNA expressions of collagen synthesized genes were increased whereas the collagen degrading genes were decreased in SM than LD muscle. Results from confocal microscopical investigation showed increased fluorescence of collagen type I and III appearing stronger in SM than LD muscle fibroblast. These results implied that the locomotion muscle had higher fibroblast growth rate, leads to produce more collagen, and cause tougher than positional muscle. This in vitro study mirrored that background toughness of various muscles in live animal is likely associated with fibroblast growth pattern, collagen synthesis and its gene expression.

  4. Collagen metabolism in obesity: the effect of weight loss

    DEFF Research Database (Denmark)

    Rasmussen, M H; Jensen, L T; Andersen, T

    1995-01-01

    OBJECTIVE: To investigate the impact of obesity, fat distribution and weight loss on collagen turnover using serum concentrations of the carboxyterminal propeptide of type I procollagen (S-PICP) and the aminoterminal propeptide of type III pro-collagen (S-PIIINP) as markers for collagen turnover...... an increased turnover of type III collagen related to obesity in general and to abdominal obesity in particular. S-PIIINP levels decreases during weight loss in obese subjects, whereas S-PICP levels seems un-related to obesity and weight loss....

  5. Collagen derived serum markers in carcinoma of the prostate

    DEFF Research Database (Denmark)

    Rudnicki, M; Jensen, L T; Iversen, P

    1995-01-01

    Three new collagen markers deriving from the collagenous matrix, e.g. carboxyterminal propeptide of type I procollagen (PICP), carboxy-terminal pyridinoline cross-linked telopeptide of type I collagen (ICTP), and aminoterminal propeptide of type III procollagen (PIIINP) were used for the diagnose......, ICTP, and PICP did not differ between these two groups. In patients with metastatic prostatic cancer all five markers were increased compared to the level measured in patients with localized cancer (p

  6. Collagen type IV at the fetal-maternal interface

    OpenAIRE

    Oefner, C M; Sharkey, A; Gardner, L; Critchley, H; Oyen, M; Moffett, A

    2015-01-01

    Introduction Extracellular matrix proteins play a crucial role in influencing the invasion of trophoblast cells. However the role of collagens and collagen type IV (col-IV) in particular at the implantation site is not clear. Methods Immunohistochemistry was used to determine the distribution of collagen types I, III, IV and VI in endometrium and decidua during the menstrual cycle and the first trimester of pregnancy. Expression of col-IV alpha chains during the reproductive cycle ...

  7. Proximal collagenous gastroenteritides:

    DEFF Research Database (Denmark)

    Nielsen, Ole Haagen; Riis, Lene Buhl; Danese, Silvio

    2014-01-01

    AIM: While collagenous colitis represents the most common form of the collagenous gastroenteritides, the collagenous entities affecting the proximal part of the gastrointestinal tract are much less recognized and possibly overlooked. The aim was to summarize the latest information through a syste...

  8. Thrombolytic therapy of acute myocardial infarction alters collagen metabolism

    DEFF Research Database (Denmark)

    Høst, N B; Hansen, S S; Jensen, L T

    1994-01-01

    The objective of the study was to monitor collagen metabolism after thrombolytic therapy. Sequential measurements of serum aminoterminal type-III procollagen propeptide (S-PIIINP) and carboxyterminal type-I procollagen propeptide (S-PICP) were made in 62 patients suspected of acute myocardial.......05). A less pronounced S-PIIINP increase was noted with tissue-plasminogen activator than with streptokinase. Thrombolytic therapy induces collagen breakdown regardless of whether acute myocardial infarction is confirmed or not. With confirmed acute myocardial infarction collagen metabolism is altered...... for at least 6 months. Furthermore, fibrin-specific and nonspecific thrombolytic agents appear to affect collagen metabolism differently....

  9. Endocytic collagen degradation

    DEFF Research Database (Denmark)

    Madsen, Daniel H.; Jürgensen, Henrik J.; Ingvarsen, Signe Ziir

    2012-01-01

    it crucially important to understand both the collagen synthesis and turnover mechanisms in this condition. Here we show that the endocytic collagen receptor, uPARAP/Endo180, is a major determinant in governing the balance between collagen deposition and degradation. Cirrhotic human livers displayed a marked...... up-regulation of uPARAP/Endo180 in activated fibroblasts and hepatic stellate cells located close to the collagen deposits. In a hepatic stellate cell line, uPARAP/Endo180 was shown to be active in, and required for, the uptake and intracellular degradation of collagen. To evaluate the functional...... groups of mice clearly revealed a fibrosis protective role of uPARAP/Endo180. This effect appeared to directly reflect the activity of the collagen receptor, since no compensatory events were noted when comparing the mRNA expression profiles of the two groups of mice in an array system focused on matrix-degrading...

  10. Moisture absorption and retention properties, and activity in alleviating skin photodamage of collagen polypeptide from marine fish skin.

    Science.gov (United States)

    Hou, Hu; Li, Bafang; Zhang, Zhaohui; Xue, Changhu; Yu, Guangli; Wang, Jingfeng; Bao, Yuming; Bu, Lin; Sun, Jiang; Peng, Zhe; Su, Shiwei

    2012-12-01

    Collagen polypeptides were prepared from cod skin. Moisture absorption and retention properties of collagen polypeptides were determined at different relative humidities. In addition, the protective effects of collagen polypeptide against UV-induced damage to mouse skin were evaluated. Collagen polypeptides had good moisture absorption and retention properties and could alleviate the damage induced by UV radiation. The action mechanisms of collagen polypeptide mainly involved enhancing immunity, reducing the loss of moisture and lipid, promoting anti-oxidative properties, inhibiting the increase of glycosaminoglycans, repairing the endogenous collagen and elastin protein fibres, and maintaining the ratio of type III to type I collagen. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Differential control of collagen synthesis by the sympathetic and renin-angiotensin systems in the rat left ventricle.

    Science.gov (United States)

    Dab, Houcine; Hachani, Rafik; Hodroj, Wassim; Sakly, Mohsen; Bricca, Giampiero; Kacem, Kamel

    2009-12-03

    In the present study, we tested the hypothesis of the indirect (via the sympathetic nervous system (SNS)) and direct (via AT1 receptors) contributions of Angiotensin II (Ang II) on the synthesis of collagen types I and III in the left ventricle (LV) in vivo. Sympathectomy and blockade of the Ang II receptor AT1 were performed alone or in combination in normotensive rats. The mRNA and protein synthesis of collagen types I and III were examined by Q-RT-PCR and immunoblotting in the LV. Collagen types I and III mRNA were decreased respectively by 53% and 22% after sympathectomy and only collagen type I mRNA was increased by 52% after AT1 receptor blockade. mRNA was not changed for collagen type I but was decreased by 25% for collagen type III after double treatment. Only collagen protein type III was decreased after sympathectomy by 12%, but collagen proteins were increased respectively for types I and III by 145% and 52% after AT1 receptor blockade and by 45% and 60% after double treatment. Deducted interpretations from our experimental approach suggest that Ang II stimulates indirectly (via SNS) and inhibits directly (via AT1 receptors) the collagen type I at transcriptional and protein levels. For collagen type III, it stimulates indirectly the transcription and inhibited directly the protein level. Therefore, the Ang II regulates collagen synthesis differently through indirect and direct pathways.

  12. [Polarized microscopic observation of the collagen change in bone healing during bone lengthening].

    Science.gov (United States)

    Zou, Pei; Li, Junhui; Li, Zhuyi

    2006-01-01

    To investigate the feature and regularity of the collagen change in bone healing during bone lengthening. Bone lengthening model was made in the middle segment of the rabbit tibia. Five days after the model was established, the bone was lengthened 1.5 mm per day for 14 days. The rabbits were put to death after elongation, 7, 14, 21, 30, 40, 50, 60 and 70 days after elongation. The distracted area of the bone was imbedded with paraffin. After being stained by the picric acid-sirius red staining, the slice was observed under polarized microscope. The features of the collagen change in the distracted bone were as follows: (1) In the fibrous tissue of the distracted area during lengthening period and the early stage after lengthening, there was not only collagen III but also much collagen I. (2) Collagen I , II and III were observed in the cartilage. (3) Collagen I, II and III were also observed in the pseudo-growth plate. (4) Collagen I took the dominance during lengthening period and the late stage after lengthening. New bone formation in bone lengthening is under the distracted force, so the collagen changes have different features compared with that in fracture healing. Collagen I, II and III can be identified by picric acid-sirius red staining and polarized microscope, so a new method for studying the collagen typing in bone repairing is provided.

  13. Collagen Quantification in Tissue Specimens.

    Science.gov (United States)

    Coentro, João Quintas; Capella-Monsonís, Héctor; Graceffa, Valeria; Wu, Zhuning; Mullen, Anne Maria; Raghunath, Michael; Zeugolis, Dimitrios I

    2017-01-01

    Collagen is the major extracellular protein in mammals. Accurate quantification of collagen is essential in the biomaterials (e.g., reproducible collagen scaffold fabrication), drug discovery (e.g., assessment of collagen in pathophysiologies, such as fibrosis), and tissue engineering (e.g., quantification of cell-synthesized collagen) fields. Although measuring hydroxyproline content is the most widely used method to quantify collagen in biological specimens, the process is very laborious. To this end, the Sircol™ Collagen Assay is widely used due to its inherent simplicity and convenience. However, this method leads to overestimation of collagen content due to the interaction of Sirius red with basic amino acids of non-collagenous proteins. Herein, we describe the addition of an ultrafiltration purification step in the process to accurately determine collagen content in tissues.

  14. Scleroderma fibroblasts: Some aspects of in vitro assessment of collagen synthesis

    International Nuclear Information System (INIS)

    Krieg, T.; Max-Planck-Institut fuer Biochemie, Muenchen; Luderschmidt, C.; Braun-Falco, O.; Weber, L.; Mueller, P.K.

    1981-01-01

    Fibroblasts were cultured from skin biopsies of patients with systemic sclerosis in different stages of the disease. In vitro synthesis of collagen was checked after a pulse with tritiated proline. The ratio between type I and type III collagen was normal in all patients. Six of seven cultures derived from patients in the active state showed an increased synthesis of collagen relative to other proteins. Addition of serum (normal and diseased) to the culture medium did not stimulate synthesis of collagen in any culture with normal collagen synthesis. (orig.) [de

  15. Scleroderma fibroblasts: some aspects of in vitro assessment of collagen synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Krieg, T.; Luderschmidt, C.; Braun-Falco, O.; Weber, L.; Mueller, P.K.

    1981-01-01

    Fibroblasts were cultured from skin biopsies of patients with systemic sclerosis in different stages of the disease. In vitro synthesis of collagen was checked after a pulse with tritiated proline. The ratio between type I and type III collagen was normal in all patients. Six of seven cultures derived from patients in the active state showed an increased synthesis of collagen relative to other proteins. Addition of serum (normal and diseased) to the culture medium did not stimulate synthesis of collagen in any culture with normal collagen synthesis.

  16. Collagen derived serum markers in carcinoma of the prostate

    DEFF Research Database (Denmark)

    Rudnicki, M; Jensen, L T; Iversen, P

    1995-01-01

    Three new collagen markers deriving from the collagenous matrix, e.g. carboxyterminal propeptide of type I procollagen (PICP), carboxy-terminal pyridinoline cross-linked telopeptide of type I collagen (ICTP), and aminoterminal propeptide of type III procollagen (PIIINP) were used for the diagnose...... of prostatic bone metastases. Blood samples were obtained prior to biopsy or TURP. Serum PICP, PIIINP and ICTP were measured with commercial available RIAs and PSA by IRMA. Serum PSA was increased in patients with local prostatic cancer compared with patients with hyperplasia (p

  17. Physiological regulation of extracellular matrix collagen and elastin in the arterial wall of rats by noradrenergic tone and angiotensin II.

    Science.gov (United States)

    Dab, Houcine; Kacem, Kamel; Hachani, Rafik; Dhaouadi, Nadra; Hodroj, Wassim; Sakly, Mohsen; Randon, Jacques; Bricca, Giampiero

    2012-03-01

    The interactions between the effects of the sympathetic nervous system (SNS) and angiotensin II (ANG II) on vascular extracellular matrix (ECM) synthesis were determined in rats. The mRNA and protein content of collagen I, collagen III and elastin in the abdominal aorta (AA) and femoral artery (FA) was investigated in Wistar-Kyoto rats treated for 5 weeks with guanethidine, a sympathoplegic, losartan, an ANG II AT1 receptor (AT1R) blocker, or both. The effects of noradrenaline (NE) and ANG II on collagen III and elastin mRNA, and the receptor involved, were tested in cultured vascular smooth muscle cells (VSMCs) in vitro. Guanethidine increased collagen types I and III and decreased elastin, while losartan had an opposite effect, although without effect on collagen III. The combination of treatments abrogated changes induced by simple treatment with collagen I and elastin, but increased collagen III mRNA in AA and not in FA. NE stimulated collagen III mRNA via β receptors and elastin via α1 and α2 receptors. ANG II stimulated collagen III but inhibited elastin mRNA via AT1R. Overall, SNS and ANG II exert opposite and antagonistic effects on major components of ECM in the vascular wall. This may be of relevance for the choice of a therapeutic strategy in vascular diseases.

  18. Collagen Homeostasis and Metabolism

    DEFF Research Database (Denmark)

    Magnusson, S Peter; Heinemeier, Katja M; Kjaer, Michael

    2016-01-01

    The musculoskeletal system and its collagen rich tissue is important for ensuring architecture of skeletal muscle, energy storage in tendon and ligaments, joint surface protection, and for ensuring the transfer of muscular forces into resulting limb movement. Structure of tendon is stable...... inactivity or immobilization of the human body will conversely result in a dramatic loss in tendon stiffness and collagen synthesis. This illustrates the importance of regular mechanical load in order to preserve the stabilizing role of the connective tissue for the overall function of the musculoskeletal...

  19. LARP6 Meets Collagen mRNA: Specific Regulation of Type I Collagen Expression

    Directory of Open Access Journals (Sweden)

    Yujie Zhang

    2016-03-01

    Full Text Available Type I collagen is the most abundant structural protein in all vertebrates, but its constitutive rate of synthesis is low due to long half-life of the protein (60–70 days. However, several hundred fold increased production of type I collagen is often seen in reparative or reactive fibrosis. The mechanism which is responsible for this dramatic upregulation is complex, including multiple levels of regulation. However, posttranscriptional regulation evidently plays a predominant role. Posttranscriptional regulation comprises processing, transport, stabilization and translation of mRNAs and is executed by RNA binding proteins. There are about 800 RNA binding proteins, but only one, La ribonucleoprotein domain family member 6 (LARP6, is specifically involved in type I collagen regulation. In the 5′untranslated region (5’UTR of mRNAs encoding for type I and type III collagens there is an evolutionally conserved stem-loop (SL structure; this structure is not found in any other mRNA, including any other collagen mRNA. LARP6 binds to the 5′SL in sequence specific manner to regulate stability of collagen mRNAs and their translatability. Here, we will review current understanding of how is LARP6 involved in posttranscriptional regulation of collagen mRNAs. We will also discuss how other proteins recruited by LARP6, including nonmuscle myosin, vimentin, serine threonine kinase receptor associated protein (STRAP, 25 kD FK506 binding protein (FKBP25 and RNA helicase A (RHA, contribute to this process.

  20. Collagen V-induced nasal tolerance downregulates pulmonary collagen mRNA gene and TGF-beta expression in experimental systemic sclerosis

    Directory of Open Access Journals (Sweden)

    Parra Edwin R

    2010-01-01

    Full Text Available Abstract Background The purpose of this study was to evaluate collagen deposition, mRNA collagen synthesis and TGF-beta expression in the lung tissue in an experimental model of scleroderma after collagen V-induced nasal tolerance. Methods Female New Zealand rabbits (N = 12 were immunized with 1 mg/ml of collagen V in Freund's adjuvant (IM. After 150 days, six immunized animals were tolerated by nasal administration of collagen V (25 μg/day (IM-TOL daily for 60 days. The collagen content was determined by morphometry, and mRNA expressions of types I, III and V collagen were determined by Real-time PCR. The TGF-beta expression was evaluated by immunostaining and quantified by point counting methods. To statistic analysis ANOVA with Bonferroni test were employed for multiple comparison when appropriate and the level of significance was determined to be p Results IM-TOL, when compared to IM, showed significant reduction in total collagen content around the vessels (0.371 ± 0.118 vs. 0.874 ± 0.282, p p p = 0.026. The lung tissue of IM-TOL, when compared to IM, showed decreased immunostaining of types I, III and V collagen, reduced mRNA expression of types I (0.10 ± 0.07 vs. 1.0 ± 0.528, p = 0.002 and V (1.12 ± 0.42 vs. 4.74 ± 2.25, p = 0.009 collagen, in addition to decreased TGF-beta expression (p Conclusions Collagen V-induced nasal tolerance in the experimental model of SSc regulated the pulmonary remodeling process, inhibiting collagen deposition and collagen I and V mRNA synthesis. Additionally, it decreased TGF-beta expression, suggesting a promising therapeutic option for scleroderma treatment.

  1. [The genetics of collagen diseases].

    Science.gov (United States)

    Kaplan, J; Maroteaux, P; Frezal, J

    1986-01-01

    Heritable disorders of collagen include Ehler-Danlos syndromes (11 types are actually known), Larsen syndrome and osteogenesis imperfecta. Their clinical, genetic and biochemical features are reviewed. Marfan syndrome is closely related to heritable disorders of collagen.

  2. A collagen-based scaffold delivering exogenous microrna-29B to modulate extracellular matrix remodeling.

    Science.gov (United States)

    Monaghan, Michael; Browne, Shane; Schenke-Layland, Katja; Pandit, Abhay

    2014-04-01

    Directing appropriate extracellular matrix remodeling is a key aim of regenerative medicine strategies. Thus, antifibrotic interfering RNA (RNAi) therapy with exogenous microRNA (miR)-29B was proposed as a method to modulate extracellular matrix remodeling following cutaneous injury. It was hypothesized that delivery of miR-29B from a collagen scaffold will efficiently modulate the extracellular matrix remodeling response and reduce maladaptive remodeling such as aggressive deposition of collagen type I after injury. The release of RNA from the scaffold was assessed and its ability to silence collagen type I and collagen type III expression was evaluated in vitro. When primary fibroblasts were cultured with scaffolds doped with miR-29B, reduced levels of collagen type I and collagen type III mRNA expression were observed for up to 2 weeks of culture. When the scaffolds were applied to full thickness wounds in vivo, reduced wound contraction, improved collagen type III/I ratios and a significantly higher matrix metalloproteinase (MMP)-8: tissue inhibitor of metalloproteinase (TIMP)-1 ratio were detected when the scaffolds were functionalized with miR-29B. Furthermore, these effects were significantly influenced by the dose of miR-29B in the collagen scaffold (0.5 versus 5 μg). This study shows a potential of combining exogenous miRs with collagen scaffolds to improve extracellular matrix remodeling following injury.

  3. Rheology of Heterotypic Collagen Networks

    NARCIS (Netherlands)

    Piechocka, I.K.; van Oosten, A.S.G.; Breuls, R.G.M.; Koenderink, G.H.

    2011-01-01

    Collagen fibrils are the main structural element of connective tissues. In many tissues, these fibrils contain two fibrillar collagens (types I and V) in a ratio that changes during tissue development, regeneration, and various diseases. Here we investigate the influence of collagen composition on

  4. Collagen markers in peritoneal dialysis patients

    DEFF Research Database (Denmark)

    Graff, J; Joffe, P; Fugleberg, S

    1995-01-01

    Possible relationships between the dialysate-to-plasma creatinine equilibration ratio (D/Pcreatinine 4 hour), duration of peritoneal dialysis treatment, number of peritonitis episodes, and mass appearance rates of three connective tissue markers [carboxyterminal propeptide of type I procollagen...... (PICP), aminoterminal propeptide of type III procollagen (PIIINP), and carboxyterminal telopeptide of type I collagen (ICTP)] were studied in 19 nondiabetic peritoneal dialysis patients. The absence of correlation between the mass appearance rates of the markers and the duration of dialysis treatment...... as well as the number of peritonitis episodes supports the concept that peritoneal dialysis does not cause persistent changes in the deposition and degradation rates of collagen. A correlation between the D/Pcreatinine 4 hr and the PICP mass appearance rates was found. Since it is unlikely...

  5. Mechanical stretching stimulates collagen synthesis via down-regulating SO2/AAT1 pathway

    Science.gov (United States)

    Liu, Jia; Yu, Wen; Liu, Yan; Chen, Selena; Huang, Yaqian; Li, Xiaohui; Liu, Cuiping; Zhang, Yanqiu; Li, Zhenzhen; Du, Jie; Tang, Chaoshu; Du, Junbao; Jin, Hongfang

    2016-01-01

    The aim of the study was to investigate the role of endogenous sulfur dioxide (SO2)/ aspartate aminotransferase 1 (AAT1) pathway in stretch-induced excessive collagen expression and its mechanism. The mechanical stretch downregulated SO2/AAT1 pathway and increased collagen I and III protein expression. Importantly, AAT1 overexpression blocked the increase in collagen I and III expression, transforming growth factor-β1 (TGF- β1) expression and phosphorylation of Smad2/3 induced by stretch, but AAT1 knockdown mimicked the increase in collagen I and III expression, TGF- β1 expression and phosphorylation of Smad2/3 induced by stretch. Mechanistically, SB431542, a TGF-β1/Smad2/3 inhibitor, eliminated excessive collagen I and III accumulation induced by AAT1 knockdown, stretch or stretch plus AAT1 knockdown. In a rat model of high pulmonary blood flow-induced pulmonary vascular collagen accumulation, AAT1 expression and SO2 content in lung tissues of rat were reduced in shunt rats with high pulmonary blood flow. Supplement of SO2 derivatives inhibited activation of TGF- β1/Smad2/3 pathway and alleviated the excessive collagen accumulation in lung tissues of shunt rats. The results suggested that deficiency of endogenous SO2/AAT1 pathway mediated mechanical stretch-stimulated abnormal collagen accumulation via TGF-β1/Smad2/3 pathway. PMID:26880260

  6. 3-D ultrastructure and collagen composition of healthy and overloaded human tendon

    DEFF Research Database (Denmark)

    Pingel, Jessica; Lu, Yinhui; Starborg, Tobias

    2014-01-01

    with regards to changes in the content of collagen type I and III (the major collagens in tendon), and changes in tendon fibroblast (tenocyte) shape and organization of the extracellular matrix (ECM). To gain new insights, we took biopsies from the tendinopathic region and flanking healthy region of Achilles...... block face-scanning electron microscopy were made on two individuals. In the tendinopathic regions, compared with the flanking healthy tissue, we observed: (i) an increase in the ratio of collagen III : I proteins; (ii) buckling of the collagen fascicles in the ECM; (iii) buckling of tenocytes...... and their nuclei; and (iv) an increase in the ratio of small-diameter : large-diameter collagen fibrils. In summary, load-induced non-rupture tendinopathy in humans is associated with localized biochemical changes, a shift from large- to small-diameter fibrils, buckling of the tendon ECM, and buckling of the cells...

  7. Collagen macromolecular drug delivery systems

    International Nuclear Information System (INIS)

    Gilbert, D.L.

    1988-01-01

    The objective of this study was to examine collagen for use as a macromolecular drug delivery system by determining the mechanism of release through a matrix. Collagen membranes varying in porosity, crosslinking density, structure and crosslinker were fabricated. Collagen characterized by infrared spectroscopy and solution viscosity was determined to be pure and native. The collagen membranes were determined to possess native vs. non-native quaternary structure and porous vs. dense aggregate membranes by electron microscopy. Collagen monolithic devices containing a model macromolecule (inulin) were fabricated. In vitro release rates were found to be linear with respect to t 1/2 and were affected by crosslinking density, crosslinker and structure. The biodegradation of the collagen matrix was also examined. In vivo biocompatibility, degradation and 14 C-inulin release rates were evaluated subcutaneously in rats

  8. Collagens - structure, function and biosynthesis.

    OpenAIRE

    Gelse, K; Poschl, E; Aigner, T

    2003-01-01

    The extracellular matrix represents a complex alloy of variable members of diverse protein families defining structural integrity and various physiological functions. The most abundant family is the collagens with more than 20 different collagen types identified so far. Collagens are centrally involved in the formation of fibrillar and microfibrillar networks of the extracellular matrix, basement membranes as well as other structures of the extracellular matrix. This review focuses on the dis...

  9. Fibrillar, fibril-associated and basement membrane collagens of the arterial wall: architecture, elasticity and remodeling under stress.

    Science.gov (United States)

    Osidak, M S; Osidak, E O; Akhmanova, M A; Domogatsky, S P; Domogatskaya, A S

    2015-01-01

    The ability of a human artery to pass through 150 million liters of blood sustaining 2 billion pulsations of blood pressure with minor deterioration depends on unique construction of the arterial wall. Viscoelastic properties of this construction enable to re-seal the occuring damages apparently without direct immediate participance of the constituent cells. Collagen structures are considered to be the elements that determine the mechanoelastic properties of the wall in parallel with elastin responsible for elasticity and resilience. Collagen scaffold architecture is the function-dependent dynamic arrangement of a dozen different collagen types composing three distinct interacting forms inside the extracellular matrix of the wall. Tightly packed molecules of collagen types I, III, V provide high tensile strength along collagen fibrils but toughness of the collagen scaffold as a whole depends on molecular bonds between distinct fibrils. Apart of other macromolecules in the extracellular matrix (ECM), collagen-specific interlinks involve microfilaments of collagen type VI, meshwork-organized collagen type VIII, and FACIT collagen type XIV. Basement membrane collagen types IV, XV, XVIII and cell-associated collagen XIII enable transmission of mechanical signals between cells and whole artery matrix. Collagen scaffold undergoes continuous remodeling by decomposition promoted with MMPs and reconstitution from newly produced collagen molecules. Pulsatile stress-strain load modulates both collagen synthesis and MMP-dependent collagen degradation. In this way the ECM structure becomes adoptive to mechanical challenges. The mechanoelastic properties of the arterial wall are changed in atherosclerosis concomitantly with collagen turnover both type-specific and dependent on the structure. Improving the feedback could be another approach to restore sufficient blood circulation.

  10. Influence of functionalized nanoparticles on conformational stability of type I collagen for possible biomedical applications.

    Science.gov (United States)

    Kandamchira, Aswathy; Selvam, Sangeetha; Marimuthu, Nidhin; Janardhanan, Sreeram Kalarical; Fathima, Nishter Nishad

    2013-12-01

    Collagen-nanoparticle interactions are vital for many biomedical applications including drug delivery and tissue engineering applications. Iron oxide nanoparticles synthesized using starch template according to our earlier reported procedures were functionalized by treating them with Gum Arabic (GA), a biocompatible polysaccharide, so as to enhance the interaction between nanoparticle surfaces and collagen. Viscosity, circular dichroism (CD) and Fourier transform infrared spectroscopy (FTIR) techniques have been used to study the collagen-nanoparticle interactions. The relative viscosity for collagen-nanoparticle conjugate was found to increase with increase in concentration of the nanoparticle within the concentration range investigated, which is due to the aggregation of protein onto the surface of nanoparticle. The CD spectra for the collagen-nanoparticle at different concentration ratios do not have much variation in the Rpn values (ratio of positive peak intensity over negative peak intensity) after functionalization with GA. The variation of molar ellipticity values for collagen-nanoparticle is due to the glycoprotein present in GA. The collagen triple helical structure is maintained after interaction with nanoparticles. The FTIR spectra of native collagen, Coll-Fs (nanoparticle without functionalization) and Coll-FsG (nanoparticle functionalized with GA) show clearly the amide I, II, III bands, with respect to collagen. The ability of polysaccharide stabilized/functionalized nanoparticles to maintain the collagen properties would help in its biomedical applications. © 2013.

  11. Collagen Conduit Versus Microsurgical Neurorrhaphy

    DEFF Research Database (Denmark)

    Boeckstyns, Michel; Sørensen, Allan Ibsen; Viñeta, Joaquin Fores

    2013-01-01

    To compare repair of acute lacerations of mixed sensory-motor nerves in humans using a collagen tube versus conventional repair.......To compare repair of acute lacerations of mixed sensory-motor nerves in humans using a collagen tube versus conventional repair....

  12. Differences in collagen distribution of healthy and regenerated periodontium. Histomorphometric study in dogs.

    Science.gov (United States)

    Souza, Sérgio L S; Macedo, Guilherme O; Silveira E Souza, Adriana M M; Taba, Mário; Novaes, Arthur B; Oliver, Constance; Jamur, Maria C; Correa, Vani M A

    2013-10-01

    Previous studies have shown that there is a relationship between periodontal disease and the distribution of collagen fibers. This study evaluated the distribution of collagen types I and III in regenerated bone and periodontal ligament, comparing them to the tissues near the regenerated area and to the healthy periodontium. In the third (P3) and fourth (P4) mandibular premolars of 5 healthy mongrel dogs, bilaterally, buccal class 2 furcation lesions were surgically created and chronified for 3 weeks. After that, full flaps were elevated and expanded polytetrafluoroethylene (e-PTFE) membranes were adapted, sutured and recovered by the flaps. Two weeks after surgery, two membranes on the same side were removed and the other membranes were removed four weeks after surgery. The dogs were euthanized at 12 weeks following placement of the e-PTFE membranes. P3 and P4 teeth as well as the second premolars (healthy control teeth) and their periodontal tissues were removed and histologically processed for Collagen Quantification (COLQ). The amount of type III collagen was higher in native bone compared to the regenerated area. For periodontal ligament, COLQ for type I collagen showed statistically significant differences (Tukeys's Multiple Comparison, p⟨0.05) between the regenerated groups and the control group. These differences were not found for type III COLQ. There are significant differences in collagen distribution among the regenerated, native and control tissues. Membrane removal 2 or 4 weeks postoperatively did not influence the collagen composition.

  13. [Effects of exogenous prostaglandin E2 on collagen content of Achilles tendon of rabbits in vivo].

    Science.gov (United States)

    Li, Hui; Tang, Kanglai; Deng, Yinshuan; Xie, Meiming; Chang, Dehai; Tao, Xu; Xu, Jianzhong

    2012-03-01

    Prostaglandin E2 (PGE2) production increases in human tendon fibroblasts after the tendon injuries and repetitive mechanical loading in vitro. To analyze the relations between PGE2 and tendinopathy by observing the changes of collagen content and proportion after the Achilles tendon of rabbits is repeatedly exposed to PGE2. Twenty-four Japanese rabbits (aged 3-4 months, weighing 2.0-2.5 kg, and male or female) were equally randomized into 2 groups according to injection dose of PGE2: low dose group (50 ng) and high dose group (500 ng). Corresponding PGE2 (0.2 mL) was injected into the middle segment of the Achilles tendon of hindlimb, the same dose saline into the same site of the other side as controls once a week for 4 weeks or 8 weeks. The Achilles tendons were harvested at 4 and 8 weeks after injection. HE staining was used to observe the cell structure and matrix, and picric acid-sirius red staining to observe the distribution and types of collagen fibers, and transmission electron microscopy was used to measure the density of the unit area and diameter of collagen fibers. HE staining showed that collagen structural damage was observed in low dose and high dose groups. Picric acid-sirius red staining showed that the content of type I collagen significantly decreased while the content of type III collagen significantly increased in experimental side of 2 groups at 4 and 8 weeks after injection when compared with control sides (P Achilles tendon of rabbit to PGE2 can cause the decrease of type I collagen, the increase of type III collagen, the reverse ratio of type I to type III, reduced unit density of collagen fibers, and thinner collagen fibers diameter, which is related with tendinopathy.

  14. Type I and III procollagen propeptides in growth hormone-deficient patients

    DEFF Research Database (Denmark)

    Jensen, L T; Jørgensen, J O; Risteli, J

    1991-01-01

    The effect of increasing doses of growth hormone on collagen synthesis in GH-treated GH-deficient patients was determined in a short-term study. The synthesis of type I and III collagen was estimated by measurements of the carboxyterminal propeptide of type I procollagen and the aminoterminal...... propeptide of type III procollagen. Type I collagen is mainly found in bone and type III collagen in loose connective tissue. We observed a GH dose dependency of both procollagen propeptides. Serum type I procollagen propeptide was significantly higher following GH doses of 4 and 6 IU/day for 14 days...... procollagen propeptide increased twice as much as type I procollagen propeptide, by 47 vs 25%, at a GH dose of 6 IU/day compared with 2 IU/day. The differences between the effects on type I and type III collagen may reflect differences in secretion or turn-over rate of collagen in bone and loose connective...

  15. Electrospun biodegradable microfibers induce new collagen formation in a rat abdominal wall defect model - a possible treatment for pelvic floor repair?

    DEFF Research Database (Denmark)

    Tarpø, Cecilie Lærke Glindtvad; Chen, Menglin; Nygaard, Jens Vinge

    2017-01-01

    Half of the female population over age 50 years will experience pelvic organ prolapse. We suggest a new approach based on tissue engineering principles to functionally reconstruct the anatomical structures of the pelvic floor. The aim of this study is to investigate the mechanical performance......, and tested for mechanical properties and the composition of connective tissue. The study showed an increase in mRNA expression for collagen-I (p = 0.0060) and collagen-III (p = 0.0086) in the 4 weeks group with bFGF. The difference was equalized at 8 and 24 weeks. No difference was found at any time...... for protein amount for collagen-I, collagen-III, and fibronectin. The amount of collagen decreased from 4 to 24 weeks but the fraction of collagen increased. The maximal load of the newly formed tissue showed no effect of bFGF at any time. Exclusively, histology showed a limited ingrowth of collagen fibers...

  16. A collagen-binding EGFR antibody fragment targeting tumors with a collagen-rich extracellular matrix

    OpenAIRE

    Hui Liang; Xiaoran Li; Bin Wang; Bing Chen; Yannan Zhao; Jie Sun; Yan Zhuang; Jiajia Shi; He Shen; Zhijun Zhang; Jianwu Dai

    2016-01-01

    Many tumors over-express collagen, which constitutes the physical scaffold of tumor microenvironment. Collagen has been considered to be a target for cancer therapy. The collagen-binding domain (CBD) is a short peptide, which could bind to collagen and achieve the sustained release of CBD-fused proteins in collagen scaffold. Here, a collagen-binding EGFR antibody fragment was designed and expressed for targeting the collagen-rich extracellular matrix in tumors. The antibody fragment (Fab) of ...

  17. Asiaticoside induces cell proliferation and collagen synthesis in human dermal fibroblasts

    Directory of Open Access Journals (Sweden)

    Linda Yulianti

    2015-08-01

    Full Text Available Asiatiocoside, a saponin component isolated from Centella asiatica can improve wound healing by promoting the proliferation of human dermal fibroblasts (HDF and synthesis of collagen. The skin-renewing cells and type I and III collagen synthesis decrease with aging, resulting in the reduction of skin elasticity and delayed wound healing. Usage of natural active compounds from plants in wound healing should be evaluated and compared to retinoic acid as an active agent that regulates wound healing. The aim of this study was to compare and evaluate the effect of asiaticoside and retinoic acid to induce greater cell proliferation and type I and III collagen synthesis in human dermal fibroblast. Methods Laboratory experiments were conducted using human dermal fibroblasts (HDF isolated from human foreskin explants. Seven passages of HDF were treated with asiaticoside and retinoic acid at several doses and incubated for 24 and 48 hours. Cell viability in all groups was tested with the MTT assay to assess HDF proliferation. Type I and III collagen synthesis was examined using the respective ELISA kits. Analysis of variance was performed to compare the treatment groups. Results Asiaticoside had significantly stronger effects on HDF proliferation than retinoic acid (p<0.05. The type III collagen production was significantly greater induction with asiaticoside compared to retinoic acid (p<0.05. Conclusion Asiaticoside induces HDF proliferation and type I and III collagen synthesis in a time- and dose-dependent pattern. Asiaticoside has a similar effect as retinoic acid on type I and type III collagen synthesis.

  18. A Quantitative Study of the Relationship between the Distribution of Different Types of Collagen and the Mechanical Behavior of Rabbit Medial Collateral Ligaments

    Science.gov (United States)

    Wan, Chao; Hao, Zhixiu; Wen, Shizhu; Leng, Huijie

    2014-01-01

    The mechanical properties of ligaments are key contributors to the stability and function of musculoskeletal joints. Ligaments are generally composed of ground substance, collagen (mainly type I and III collagen), and minimal elastin fibers. However, no consensus has been reached about whether the distribution of different types of collagen correlates with the mechanical behaviors of ligaments. The main objective of this study was to determine whether the collagen type distribution is correlated with the mechanical properties of ligaments. Using axial tensile tests and picrosirius red staining-polarization observations, the mechanical behaviors and the ratios of the various types of collagen were investigated for twenty-four rabbit medial collateral ligaments from twenty-four rabbits of different ages, respectively. One-way analysis of variance was used in the comparison of the Young's modulus in the linear region of the stress-strain curves and the ratios of type I and III collagen for the specimens (the mid-substance specimens of the ligaments) with different ages. A multiple linear regression was performed using the collagen contents (the ratios of type I and III collagen) and the Young's modulus of the specimens. During the maturation of the ligaments, the type I collagen content increased, and the type III collagen content decreased. A significant and strong correlation () was identified by multiple linear regression between the collagen contents (i.e., the ratios of type I and type III collagen) and the mechanical properties of the specimens. The collagen content of ligaments might provide a new perspective for evaluating the linear modulus of global stress-strain curves for ligaments and open a new door for studying the mechanical behaviors and functions of connective tissues. PMID:25062068

  19. A quantitative study of the relationship between the distribution of different types of collagen and the mechanical behavior of rabbit medial collateral ligaments.

    Science.gov (United States)

    Wan, Chao; Hao, Zhixiu; Wen, Shizhu; Leng, Huijie

    2014-01-01

    The mechanical properties of ligaments are key contributors to the stability and function of musculoskeletal joints. Ligaments are generally composed of ground substance, collagen (mainly type I and III collagen), and minimal elastin fibers. However, no consensus has been reached about whether the distribution of different types of collagen correlates with the mechanical behaviors of ligaments. The main objective of this study was to determine whether the collagen type distribution is correlated with the mechanical properties of ligaments. Using axial tensile tests and picrosirius red staining-polarization observations, the mechanical behaviors and the ratios of the various types of collagen were investigated for twenty-four rabbit medial collateral ligaments from twenty-four rabbits of different ages, respectively. One-way analysis of variance was used in the comparison of the Young's modulus in the linear region of the stress-strain curves and the ratios of type I and III collagen for the specimens (the mid-substance specimens of the ligaments) with different ages. A multiple linear regression was performed using the collagen contents (the ratios of type I and III collagen) and the Young's modulus of the specimens. During the maturation of the ligaments, the type I collagen content increased, and the type III collagen content decreased. A significant and strong correlation (R2 = 0.839, P < 0.05) was identified by multiple linear regression between the collagen contents (i.e., the ratios of type I and type III collagen) and the mechanical properties of the specimens. The collagen content of ligaments might provide a new perspective for evaluating the linear modulus of global stress-strain curves for ligaments and open a new door for studying the mechanical behaviors and functions of connective tissues.

  20. A quantitative study of the relationship between the distribution of different types of collagen and the mechanical behavior of rabbit medial collateral ligaments.

    Directory of Open Access Journals (Sweden)

    Chao Wan

    Full Text Available The mechanical properties of ligaments are key contributors to the stability and function of musculoskeletal joints. Ligaments are generally composed of ground substance, collagen (mainly type I and III collagen, and minimal elastin fibers. However, no consensus has been reached about whether the distribution of different types of collagen correlates with the mechanical behaviors of ligaments. The main objective of this study was to determine whether the collagen type distribution is correlated with the mechanical properties of ligaments. Using axial tensile tests and picrosirius red staining-polarization observations, the mechanical behaviors and the ratios of the various types of collagen were investigated for twenty-four rabbit medial collateral ligaments from twenty-four rabbits of different ages, respectively. One-way analysis of variance was used in the comparison of the Young's modulus in the linear region of the stress-strain curves and the ratios of type I and III collagen for the specimens (the mid-substance specimens of the ligaments with different ages. A multiple linear regression was performed using the collagen contents (the ratios of type I and III collagen and the Young's modulus of the specimens. During the maturation of the ligaments, the type I collagen content increased, and the type III collagen content decreased. A significant and strong correlation (R2 = 0.839, P < 0.05 was identified by multiple linear regression between the collagen contents (i.e., the ratios of type I and type III collagen and the mechanical properties of the specimens. The collagen content of ligaments might provide a new perspective for evaluating the linear modulus of global stress-strain curves for ligaments and open a new door for studying the mechanical behaviors and functions of connective tissues.

  1. Release of antibiotics from collagen dressing.

    Science.gov (United States)

    Grzybowski, J; Antos-Bielska, M; Ołdak, E; Trafny, E A

    1997-01-01

    Our new collagen dressing has been developed recently. Three types (A, B, and C) of the dressing were prepared in this study. Each type contained bacitracin, neomycin or colistin. The antibiotic was input into: i. collagen sponge (CS)--type A, ii. layer of limited hydrophobicity (LLH)--type B, and iii. into both CS and LLH layers--type C. The final concentration of the antibiotic that resulted from the loading level was 2 mg/cm2 for the dressings of type A and B and 4 mg/cm2 for the dressing of type C. The antibiotics were then extracted from the pieces of dressings for two days through dialysis membrane. Susceptibility of 54 bacterial strains (S. aureus, P. aeruginosa, and Acinetobacter) isolated from burn wounds were tested to the three antibiotics used for preparation of the dressings. The results of the study evidenced that efficiency of released of antibiotics into the extracts depended on the kind of antibiotic and on the type of dressing. The concentration of the antibiotics proved to be much higher than MIC90 values of the bacterial isolates tested in respect to their susceptibility. The dressing containing mixture of the three antibiotics in two layers--CS and LLH is now considered as potentially effective for care of infected wounds. It may be useful for the treatment of infected wounds or for profilaxis of contaminated wounds, ensuring: i. sufficient antimicrobial activity in wound, and ii. optimal wound environment for the presence of collagenic biomaterial on the damaged tissue.

  2. Regulation of collagen biosynthesis in cultured bovine aortic smooth muscle cells

    International Nuclear Information System (INIS)

    Stepp, M.A.

    1986-01-01

    Aortic smooth muscles cells have been implicated in the etiology of lesions which occur in atherosclerosis and hypertension. Both diseases involve proliferation of smooth muscle cells and accumulation of excessive amounts of extracellular matrix proteins, including collagen type I and type III produced by the smooth muscle cells. To better understand the sites of regulation of collagen biosynthesis and to correlate these with the growth rate of the cells, cultured bovine aortic smooth muscle cells were studied as a function of the number of days (3 to 14) in second passage. Cells grew rapidly up to day 6 when confluence was reached. The total incorporation of [ 3 H]-proline into proteins was highest at day 3 and decreased to a constant level after the cultures reached confluence. In contrast, collagen protein production was lowest before confluence and continued to increase over the entire time course of the experiments. cDNA clones for the α1 and α2 chains of type I and the α1 chain of type III collagen were used to quantitate the steady state level of collagen mRNAs. RNA was tested in a cell-free translation system. Changes in the translational activity of collagen mRNAs parallelled the observed increases in collagen protein production. Thus, at later time points, collagen mRNAs are more active in directing synthesis of preprocollagens, even though less collagen mRNA is present. The conclusion is that the site of regulation of the expression of collagen genes is a function of the growth rate of cultured smooth muscle cells

  3. Evaluation of human collagen biomaterials in the healing of colonic anastomoses in dogs.

    Science.gov (United States)

    Mutter, D; Aprahamian, M; Tiollier, J; Sonzini, P; Marescaux, J

    1997-04-01

    To investigate the ability of human collagen biomaterials to secure colonic anastomoses in dogs and to evaluate the biocompatibility of anastomotic protection patches (APP). Experimental open study. Experimental research centre, France. 21 mongrel dogs randomised into three groups of 7 each. Standard transverse colonic end-to-end anastomoses were secured with two-layer oxidised collagen I + III sponge covered with thin crosslinked collagen IV film (APP 1) glued around the suture (n = 7); two-layer oxidised collagen I + III sponge covered with thin non-crosslinked collagen I + III film patch (APP 2) (n = 7); or sealed by fibrin sealant (n = 7), which acted as a controls. Gross examination, radiological control (barium enemas), and microscopic examination on day 35 postoperatively. Gross clinical and radiological examinations on day 35 showed normal wound healing in all but one dog in which the anastomoses had occluded by day 16. There was significantly less stricturing with the APP 2 patch (p < 0.05 compared with the controls). Microscopic examination showed complete absorption of the APP 2 patches as well as quicker mucosal and extracellular matrix repair than controls. The APP 1 patch gave the best healing of the muscular layer but did not reduce anastomosis stricturing, and was not totally absorbed. Collagen supporting devices do not alter healing of the large bowel. Encircling patches do not increase the number of adhesions or the rate of anastomotic stricturing and a thin fibrillar collagen I + III dense layer may even improve it. The speed of absorption of the patch depends on the type of dense collagen film. These results argue for a prospective clinical evaluation in humans.

  4. Changes in collagen metabolites in serum after cemented hip and knee arthroplasty

    DEFF Research Database (Denmark)

    Joerring, S; Jensen, L T

    1993-01-01

    Markers of types I and III collagen turnover were measured in serial blood samples collected preoperatively and 60 days after surgery in 13 patients undergoing cemented total hip arthroplasty and 11 patients undergoing cemented total knee arthroplasty. The markers were the carboxyterminal extension....... We suggest that the changes in serum PICP and serum PIIINP reflect collagen formation in healing soft connective tissue 60 days after cemented hip or knee arthroplasty....

  5. PHAGOCYTOSIS AND REMODELING OF COLLAGEN MATRICES

    OpenAIRE

    Abraham, Leah C.; Dice, J Fred.; Lee, Kyongbum; Kaplan, David L.

    2007-01-01

    The biodegradation of collagen and the deposition of new collagen-based extracellular matrices are of central importance in tissue remodeling and function. Similarly, for collagen-based biomaterials used in tissue engineering, the degradation of collagen scaffolds with accompanying cellular infiltration and generation of new extracellular matrix is critical for integration of in vitro grown tissues in vivo. In earlier studies we observed significant impact of collagen structure on primary lun...

  6. and collagen III propeptides (PIIINP) in juvenile rheumatoid a

    African Journals Online (AJOL)

    Ehab

    Laboratory, clinical and radiological evaluation methods were re-performed after 3 months of proper treatment. A third radiological evaluation was done one year after the first evaluation. Results: Serum PIIINP was significantly elevated in JRA patients (12.8±8.7) μg/L in comparison to healthy controls (7.0±1.9 μg/L, p<0.05).

  7. FISH SKIN ISOLATED COLLAGEN CRYOGELS FOR TISSUE ENGINEERING APPLICATIONS: PURIFICATION, SYNTHESIS AND CHARACTERIZATION

    Directory of Open Access Journals (Sweden)

    Nimet Bölgen

    2016-09-01

    Full Text Available Tissue engineering aims regenerating damaged tissues by using porous scaffolds, cells and bioactive agents. The scaffolds are produced from a variety of natural and synthetic polymers. Collagen is a natural polymer widely used for scaffold production in the late years because of its being the most important component of the connective tissue and biocompatibility. Cryogelation is a relatively simple technique compared to other scaffold production methods, which enables to produce interconnected porous matrices from the frozen reaction mixtures of polymers or monomeric precursors. Considering these, collagen was isolated in this study from fish skin which is a non-commercial waste material, and scaffolds were produced from this collagen by cryogelation method. By SEM analysis, porous structure of collagen, and by UV-Vis analysis protein structure was proven, and by Zeta potential iso-electrical point of the protein was determined, and,  Amit A, Amit B, Amit I, Amit II and Amit III characteristical peaks were demonstrated by FTIR analysis. The collagen isolation yield was, 14.53% for acid soluble collagen and 2.42% for pepcin soluble collagen. Scaffolds were produced by crosslinking isolated acid soluble collagen with glutaraldehyde at cryogenic conditions. With FTIR analysis, C=N bond belonging to gluteraldehyde reaction with collagen was found to be at 1655 cm-1. It was demonstrated by SEM analysis that collagen and glutaraldeyhde concentration had significant effects on the pore morphology, diameter and wall thickness of the cryogels, which in turned changed the swelling ratio and degradation profiles of the matrices. In this study, synthesis and characterization results of a fish skin isolated collagen cryogel scaffold that may be potentially used in the regeneration of damaged tissues are presented.

  8. GH and IGF-I levels are positively associated with musculotendinous collagen expression: Experiments in acromegalic and GHD patients

    DEFF Research Database (Denmark)

    Doessing, Simon; Holm, Lars; Heinemeier, Katja

    2010-01-01

    OBJECTIVE: Disproportionate growth of musculoskeletal tissue is a major cause of morbidity in both acromegalic (ACRO) and GH-deficient (GHD) patients. GH/IGF1 is likely to play an important role in the regulation of tendon and muscle collagen. We hypothesized that the local production of collagen...... is associated with the level of GH/IGF1.DESIGN AND METHODS: As primary outcomes, collagen mRNA expression and collagen protein fractional synthesis rate (FSR) were determined locally in skeletal muscle and tendon in nine ACRO and nine GHD patients. Moreover, muscle myofibrillar protein synthesis and tendon...... collagen morphology were determined.RESULTS AND CONCLUSIONS: Muscle collagen I and III mRNA expression was higher in ACRO patients versus GHD patients (PIGF1Ea and IGF1Ec...

  9. Enhanced stabilization of collagen by furfural.

    Science.gov (United States)

    Lakra, Rachita; Kiran, Manikantan Syamala; Usha, Ramamoorthy; Mohan, Ranganathan; Sundaresan, Raja; Korrapati, Purna Sai

    2014-04-01

    Furfural (2-furancarboxaldehyde), a product derived from plant pentosans, has been investigated for its interaction with collagen. Introduction of furfural during fibril formation enhanced the thermal and mechanical stability of collagen. Collagen films treated with furfural exhibited higher denaturation temperature (Td) (pFurfural and furfural treated collagen films did not have any cytotoxic effect. Rheological characterization showed an increase in shear stress and shear viscosity with increasing shear rate for treated collagen. Circular dichroism (CD) studies indicated that the furfural did not have any impact on triple helical structure of collagen. Scanning electron microscopy (SEM) of furfural treated collagen exhibited small sized porous structure in comparison with untreated collagen. Thus this study provides an alternate ecologically safe crosslinking agent for improving the stability of collagen for biomedical and industrial applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Quantitative Characterization of Collagen in the Fibrotic Capsule Surrounding Implanted Polymeric Microparticles through Second Harmonic Generation Imaging.

    Science.gov (United States)

    Akilbekova, Dana; Bratlie, Kaitlin M

    2015-01-01

    The collagenous capsule formed around an implant will ultimately determine the nature of its in vivo fate. To provide a better understanding of how surface modifications can alter the collagen orientation and composition in the fibrotic capsule, we used second harmonic generation (SHG) microscopy to evaluate collagen organization and structure generated in mice subcutaneously injected with chemically functionalized polystyrene particles. SHG is sensitive to the orientation of a molecule, making it a powerful tool for measuring the alignment of collagen fibers. Additionally, SHG arises from the second order susceptibility of the interrogated molecule in response to the electric field. Variation in these tensor components distinguishes different molecular sources of SHG, providing collagen type specificity. Here, we demonstrated the ability of SHG to differentiate collagen type I and type III quantitatively and used this method to examine fibrous capsules of implanted polystyrene particles. Data presented in this work shows a wide range of collagen fiber orientations and collagen compositions in response to surface functionalized polystyrene particles. Dimethylamino functionalized particles were able to form a thin collagenous matrix resembling healthy skin. These findings have the potential to improve the fundamental understanding of how material properties influence collagen organization and composition quantitatively.

  11. Quantitative Characterization of Collagen in the Fibrotic Capsule Surrounding Implanted Polymeric Microparticles through Second Harmonic Generation Imaging.

    Directory of Open Access Journals (Sweden)

    Dana Akilbekova

    Full Text Available The collagenous capsule formed around an implant will ultimately determine the nature of its in vivo fate. To provide a better understanding of how surface modifications can alter the collagen orientation and composition in the fibrotic capsule, we used second harmonic generation (SHG microscopy to evaluate collagen organization and structure generated in mice subcutaneously injected with chemically functionalized polystyrene particles. SHG is sensitive to the orientation of a molecule, making it a powerful tool for measuring the alignment of collagen fibers. Additionally, SHG arises from the second order susceptibility of the interrogated molecule in response to the electric field. Variation in these tensor components distinguishes different molecular sources of SHG, providing collagen type specificity. Here, we demonstrated the ability of SHG to differentiate collagen type I and type III quantitatively and used this method to examine fibrous capsules of implanted polystyrene particles. Data presented in this work shows a wide range of collagen fiber orientations and collagen compositions in response to surface functionalized polystyrene particles. Dimethylamino functionalized particles were able to form a thin collagenous matrix resembling healthy skin. These findings have the potential to improve the fundamental understanding of how material properties influence collagen organization and composition quantitatively.

  12. Interleukin-1 alpha modulates collagen gene expression in cultured synovial cells.

    Science.gov (United States)

    Mauviel, A; Teyton, L; Bhatnagar, R; Penfornis, H; Laurent, M; Hartmann, D; Bonaventure, J; Loyau, G; Saklatvala, J; Pujol, J P

    1988-01-01

    The effects of porcine interleukin-1 (IL-1) alpha on collagen production were studied in cultured human rheumatoid synovial cells. Addition of 0.05-5 ng of IL-1/ml into the cultures resulted in a dose-dependent decreased rate of collagen released into the medium over 24 h. To determine whether this inhibition was due to secondary action of prostaglandin E2 (PGE2) secreted in response to IL-1, cultures were incubated in presence of various inhibitors of arachidonate metabolism. Depending on the cell strains, these inhibitors were able to suppress or diminish the effect of IL-1, suggesting that PGE2 is involved in the mechanism. Depression of collagen production caused by IL-1 mainly affected type I collagen and therefore led to a change in the type I/type III collagen ratio in the extracellular medium. Steady-state levels of mRNA for types I and III procollagens were estimated by dot-blot hybridization and compared with the amounts of respective collagens produced in the same cultures. IL-1 generally increased procollagen type I mRNA, but to a variable extent, as did indomethacin (Indo). Depending on the cell strain, the combination of indo and IL-1 could elevate the mRNA level of type I procollagen compared with Indo alone. These results did not correlate with the production rate of collagen in the medium, which was diminished by exposure to IL-1. The level of mRNA for collagen type III was not greatly changed by incubation with IL-1, and a better correlation was generally observed with the amount of type III collagen found in the medium. These data suggest that an additional control mechanism at translational or post-translational level must exist, counterbalancing the stimulatory effect of IL-1 on collagen mRNA transcription. It is likely that IL-1 could modulate the production of collagen in synovial cells by an interplay of different mechanisms, some of them limiting the effect of primary elevation of the steady-state mRNA level. Images Fig. 3. Fig. 4. Fig. 5

  13. Adrenomedullin and adrenotensin regulate collagen synthesis and proliferation in pulmonary arterial smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Li, W. [School of Control Science and Engineering, Biomedical Engineering Institute, Shandong University, Jinan, Shandong (China); Kong, Q.Y.; Zhao, C.F. [Department of Pediatrics, Qilu Hospital, Shandong University, Jinan, Shandong (China); Zhao, F. [Department of Medicine, Weill Medical College of Cornell University, New York, NY (United States); Li, F.H.; Xia, W. [Department of Pediatrics, Qilu Hospital, Shandong University, Jinan, Shandong (China); Wang, R. [Key Laboratory of Cardiovascular Remodeling and Function Research, Qilu Hospital, Shandong University, Jinan, Shandong (China); Hu, Y.M. [School of Control Science and Engineering, Biomedical Engineering Institute, Shandong University, Jinan, Shandong (China); Hua, M. [Shandong Institute of Scientific and Technical Information, Jinan, Shandong (China)

    2013-12-10

    To understand the pathophysiological mechanisms of pulmonary arterial smooth muscle cell (PASMC) proliferation and extracellular-matrix accumulation in the development of pulmonary hypertension and remodeling, this study determined the effects of different doses of adrenomedullin (ADM) and adrenotensin (ADT) on PASMC proliferation and collagen synthesis. The objective was to investigate whether extracellular signal-regulated kinase (ERK1/2) signaling was involved in ADM- and ADT-stimulated proliferation of PASMCs in 4-week-old male Wistar rats (body weight: 100-150 g, n=10). The proliferation of PASMCs was examined by 5-bromo-2-deoxyuridine incorporation. A cell growth curve was generated by the Cell Counting Kit-8 method. Expression of collagen I, collagen III, and phosphorylated ERK1/2 (p-ERK1/2) was evaluated by immunofluorescence. The effects of different concentrations of ADM and ADT on collagen I, collagen III, and p-ERK1/2 protein expression were determined by immunoblotting. We also investigated the effect of PD98059 inhibition on the expression of p-ERK1/2 protein by immunoblotting. ADM dose-dependently decreased cell proliferation, whereas ADT dose-dependently increased it; and ADM and ADT inhibited each other with respect to their effects on the proliferation of PASMCs. Consistent with these results, the expression of collagen I, collagen III, and p-ERK1/2 in rat PASMCs decreased after exposure to ADM but was upregulated after exposure to ADT. PD98059 significantly inhibited the downregulation by ADM and the upregulation by ADT of p-ERK1/2 expression. We conclude that ADM inhibited, and ADT stimulated, ERK1/2 signaling in rat PASMCs to regulate cell proliferation and collagen expression.

  14. Fracture mechanics of collagen fibrils

    DEFF Research Database (Denmark)

    Svensson, Rene B; Mulder, Hindrik; Kovanen, Vuokko

    2013-01-01

    Tendons are important load-bearing structures, which are frequently injured in both sports and work. Type I collagen fibrils are the primary components of tendons and carry most of the mechanical loads experienced by the tissue, however, knowledge of how load is transmitted between and within...... fibrils is limited. The presence of covalent enzymatic cross-links between collagen molecules is an important factor that has been shown to influence mechanical behavior of the tendons. To improve our understanding of how molecular bonds translate into tendon mechanics, we used an atomic force microscopy...... technique to measure the mechanical behavior of individual collagen fibrils loaded to failure. Fibrils from human patellar tendons, rat-tail tendons (RTTs), NaBH₄ reduced RTTs, and tail tendons of Zucker diabetic fat rats were tested. We found a characteristic three-phase stress-strain behavior in the human...

  15. Collagen crosslinks in chondromalacia of the patella.

    Science.gov (United States)

    Väätäinen, U; Kiviranta, I; Jaroma, H; Arokosi, J; Tammi, M; Kovanen, V

    1998-02-01

    The aim of the study was to determine collagen concentration and collagen crosslinks in cartilage samples from chondromalacia of the patella. To study the extracellular matrix alterations associated to chondromalacia, we determined the concentration of collagen (hydroxyproline) and its hydroxylysylpyridinoline and lysylpyridinoline crosslinks from chondromalacia foci of the patellae in 12 patients and 7 controls from apparently normal cadavers. The structure of the collagen network in 8 samples of grades II-IV chondromalacia was examined under polarized light microscopy. The full-thickness cartilage samples taken with a surgical knife from chondromalacia lesions did not show changes in collagen, hydroxylysylpyridinoline and lysylpyridinoline concentration as compared with the controls. Polarized light microscopy showed decreased birefringence in the superficial cartilage of chondromalacia lesions, indicating disorganization or disappearance of collagen fibers in this zone. It is concluded that the collagen network shows gradual disorganization with the severity of chondromalacia lesion of the patella without changes in the concentration or crosslinks of collagen.

  16. Progress towards discovery of antifibrotic drugs targeting synthesis of type I collagen

    KAUST Repository

    Fritz, Dillon Jeffery; Cai, Le; Stefanovic, Lela; Stefanovic, Branko

    2011-01-01

    Type I collagen is the most abundant protein in human body. Fibrosis is characterized by excessive synthesis of type I collagen in parenchymal organs. It is a leading cause of morbidity and mortality worldwide, about 45% of all natural deaths are attributable to some fibroproliferative disease. There is no cure for fibrosis. To find specific antifibrotic therapy targeting type I collagen, critical molecular interactions regulating its synthesis must be elucidated. Type I and type III collagen mRNAs have a unique sequence element at the 5' end, the 5' stem-loop. This stem-loop is not found in any other mRNA. We cloned LARP6 as the protein which binds collagen 5' stem-loop with high affinity and specificity. Mutation of the 5' stem-loop or knock down of LARP6 greatly diminishes collagen expression. Mice with mutation of the 5' stem-loop are resistant to development of liver fibrosis. LARP6 associates collagen mRNAs with filaments composed of nonmuscle myosin; disruption of these filaments abolishes synthesis of type I collagen. Thus, LARP6 dependent collagen synthesis is the specific mechanism of high collagen expression seen in fibrosis. We developed fluorescence polarization (FP) method to screen for drugs that can inhibit binding of LARP6 to 5' stem-loop RNA. FP is high when LARP6 is bound, but decreases to low levels when the binding is competed out. Thus, by measuring decrease in FP it is possible to identify chemical compounds that can dissociate LARP6 from the 5' stem-loop. The method is simple, fast and suitable for high throughput screening. © 2011 Bentham Science Publishers Ltd.

  17. Progress towards discovery of antifibrotic drugs targeting synthesis of type I collagen

    KAUST Repository

    Fritz, Dillon Jeffery

    2011-08-01

    Type I collagen is the most abundant protein in human body. Fibrosis is characterized by excessive synthesis of type I collagen in parenchymal organs. It is a leading cause of morbidity and mortality worldwide, about 45% of all natural deaths are attributable to some fibroproliferative disease. There is no cure for fibrosis. To find specific antifibrotic therapy targeting type I collagen, critical molecular interactions regulating its synthesis must be elucidated. Type I and type III collagen mRNAs have a unique sequence element at the 5\\' end, the 5\\' stem-loop. This stem-loop is not found in any other mRNA. We cloned LARP6 as the protein which binds collagen 5\\' stem-loop with high affinity and specificity. Mutation of the 5\\' stem-loop or knock down of LARP6 greatly diminishes collagen expression. Mice with mutation of the 5\\' stem-loop are resistant to development of liver fibrosis. LARP6 associates collagen mRNAs with filaments composed of nonmuscle myosin; disruption of these filaments abolishes synthesis of type I collagen. Thus, LARP6 dependent collagen synthesis is the specific mechanism of high collagen expression seen in fibrosis. We developed fluorescence polarization (FP) method to screen for drugs that can inhibit binding of LARP6 to 5\\' stem-loop RNA. FP is high when LARP6 is bound, but decreases to low levels when the binding is competed out. Thus, by measuring decrease in FP it is possible to identify chemical compounds that can dissociate LARP6 from the 5\\' stem-loop. The method is simple, fast and suitable for high throughput screening. © 2011 Bentham Science Publishers Ltd.

  18. Modeling pulmonary fibrosis by abnormal expression of telomerase/apoptosis/collagen V in experimental usual interstitial pneumonia

    International Nuclear Information System (INIS)

    Parra, E.R.; Pincelli, M.S.; Teodoro, W.R.; Velosa, A.P.P.; Martins, V.; Rangel, M.P.; Barbas-Filho, J.V.; Capelozzi, V.L.

    2014-01-01

    Limitations on tissue proliferation capacity determined by telomerase/apoptosis balance have been implicated in pathogenesis of idiopathic pulmonary fibrosis. In addition, collagen V shows promise as an inductor of apoptosis. We evaluated the quantitative relationship between the telomerase/apoptosis index, collagen V synthesis, and epithelial/fibroblast replication in mice exposed to butylated hydroxytoluene (BHT) at high oxygen concentration. Two groups of mice were analyzed: 20 mice received BHT, and 10 control mice received corn oil. Telomerase expression, apoptosis, collagen I, III, and V fibers, and hydroxyproline were evaluated by immunohistochemistry, in situ detection of apoptosis, electron microscopy, immunofluorescence, and histomorphometry. Electron microscopy confirmed the presence of increased alveolar epithelial cells type 1 (AEC1) in apoptosis. Immunostaining showed increased nuclear expression of telomerase in AEC type 2 (AEC2) between normal and chronic scarring areas of usual interstitial pneumonia (UIP). Control lungs and normal areas from UIP lungs showed weak green birefringence of type I and III collagens in the alveolar wall and type V collagen in the basement membrane of alveolar capillaries. The increase in collagen V was greater than collagens I and III in scarring areas of UIP. A significant direct association was found between collagen V and AEC2 apoptosis. We concluded that telomerase, collagen V fiber density, and apoptosis evaluation in experimental UIP offers the potential to control reepithelization of alveolar septa and fibroblast proliferation. Strategies aimed at preventing high rates of collagen V synthesis, or local responses to high rates of cell apoptosis, may have a significant impact in pulmonary fibrosis

  19. Modeling pulmonary fibrosis by abnormal expression of telomerase/apoptosis/collagen V in experimental usual interstitial pneumonia

    Energy Technology Data Exchange (ETDEWEB)

    Parra, E.R.; Pincelli, M.S. [Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Teodoro, W.R.; Velosa, A.P.P. [Disciplina de Reumatologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Martins, V.; Rangel, M.P.; Barbas-Filho, J.V.; Capelozzi, V.L. [Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil)

    2014-06-04

    Limitations on tissue proliferation capacity determined by telomerase/apoptosis balance have been implicated in pathogenesis of idiopathic pulmonary fibrosis. In addition, collagen V shows promise as an inductor of apoptosis. We evaluated the quantitative relationship between the telomerase/apoptosis index, collagen V synthesis, and epithelial/fibroblast replication in mice exposed to butylated hydroxytoluene (BHT) at high oxygen concentration. Two groups of mice were analyzed: 20 mice received BHT, and 10 control mice received corn oil. Telomerase expression, apoptosis, collagen I, III, and V fibers, and hydroxyproline were evaluated by immunohistochemistry, in situ detection of apoptosis, electron microscopy, immunofluorescence, and histomorphometry. Electron microscopy confirmed the presence of increased alveolar epithelial cells type 1 (AEC1) in apoptosis. Immunostaining showed increased nuclear expression of telomerase in AEC type 2 (AEC2) between normal and chronic scarring areas of usual interstitial pneumonia (UIP). Control lungs and normal areas from UIP lungs showed weak green birefringence of type I and III collagens in the alveolar wall and type V collagen in the basement membrane of alveolar capillaries. The increase in collagen V was greater than collagens I and III in scarring areas of UIP. A significant direct association was found between collagen V and AEC2 apoptosis. We concluded that telomerase, collagen V fiber density, and apoptosis evaluation in experimental UIP offers the potential to control reepithelization of alveolar septa and fibroblast proliferation. Strategies aimed at preventing high rates of collagen V synthesis, or local responses to high rates of cell apoptosis, may have a significant impact in pulmonary fibrosis.

  20. Building blocks of Collagen based biomaterial devices

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Building blocks of Collagen based biomaterial devices. Collagen as a protein. Collagen in tissues and organs. Stabilizing and cross linking agents. Immunogenicity. Hosts (drugs). Controlled release mechanisms of hosts. Biodegradability, workability into devices ...

  1. Histone Deacetylase Inhibition Downregulates Collagen 3A1 in Fibrotic Lung Fibroblasts

    Directory of Open Access Journals (Sweden)

    Victor J. Thannickal

    2013-09-01

    Full Text Available Idiopathic pulmonary fibrosis (IPF is a deadly disease characterized by chronic inflammation and excessive collagen accumulation in the lung. Myofibroblasts are the primary collagen-producing cells in pulmonary fibrosis. Histone deacetylase inhibitor (HDACi can affect gene expression, and some, such as suberoylanilide hydroxamic acid (SAHA, are US FDA approved for cancer treatment. In this study, we investigated SAHA’s effects on the expression of collagen III alpha 1 (COL3A1 in primary human IPF fibroblasts and in a murine model of pulmonary fibrosis. We observed that increased COL3A1 expression in IPF fibroblasts can be substantially reduced by SAHA treatment at the level of transcription as detected by RT-PCR; collagen III protein level was also reduced, as detected by Western blots and immunofluorescence. The deacetylation inhibitor effect of SAHA was verified by observing higher acetylation levels of both histone H3 and H4 in treated IPF cells. Chromatin immunoprecipitation (ChIP experiments demonstrated that the reduced expression of COL3A1 by SAHA is with increased association of the repressive chromatin marker, H3K27Me3, and decreased association of the active chromatin marker, H3K9Ac. In our murine model of bleomycin-induced pulmonary fibrosis, the SAHA treated group demonstrated significantly less collagen III, as detected by immunohistochemistry. Our data indicate that the HDACi SAHA alters the chromatin associated with COL3A1, resulting in its decreased expression.

  2. Connective matrix organization in human pulmonary fibrosis. Collagen polymorphism analysis in fibrotic deposits by immunohistological methods.

    Science.gov (United States)

    Takiya, C; Peyrol, S; Cordier, J F; Grimaud, J A

    1983-01-01

    In the interstitium of the alveolar septa in the peripheral parts of the lung, four molecular types of collagen (I, III, IV and V) each with different morphological appearances, can be identified. The structural integrity of collagens accounts for the physiological efficiency of the lung. Fibrous thickening of alveolar septa is an invariable result of various diseases affecting the interstitium of the lung. The light and electron microscopic findings, and the immunological typing of collagens in six cases of fibrotic alveolar disease, are described. In the alveolar septa, two different compartments (the alveolo-capillary junction and the supportive axis) were affected by fibrosis: the alveolo-capillary junction was widened by the addition of interstitial collagens to basement membranes. In the axis, the increase of interstitial (types I and III) collagen gave rise to different patterns of connective matrix organization, graded as Loose or Dense depending on quantitative alterations of the type I/III ratio. The mode of organization of the fibrotic lung connective matrix, which depends on the quality of deposits in the matrix, may be correlated with the evolution of interstitial pulmonary fibrosis, in terms of its stability, remodelling ability and reversibility.

  3. Comparison of three types of chondrocytes in collagen scaffolds for cartilage tissue engineering

    International Nuclear Information System (INIS)

    Zhang Lu; Spector, Myron

    2009-01-01

    The objective of this study was to compare the chondrogenesis in type I and II collagen scaffolds seeded with chondrocytes from three types of cartilage, after four weeks of culture: auricular (AU), articular (AR) and meniscal (ME). Related aims were to investigate the expression of a contractile muscle actin isoform, α-smooth muscle actin (SMA), in the cells in the scaffold and to determine the presence of a lubricating glycoprotein, lubricin, in the constructs. Adult goat AU, AR and ME chondrocytes were seeded into two types of collagen scaffolds: type II collagen and type I/III collagen. After four weeks of culture, the constructs were prepared for histochemical and immunohistochemical analysis of the distribution of glycosaminoglycan (GAG), types I and II collagen, elastin, SM and lubricin. AU constructs contained substantially more tissue than the AR and ME samples. The AU constructs exhibited neocartilage, but no elastin. There were no notable differences between the type I and II collagen scaffolds. Novel findings were the expression of SMA by the AU cells in the scaffolds and the presence of lubricin in the AR and AU constructs. AU cells have the capability to produce cartilage in collagen scaffolds under conditions in which there is little histogenesis by AR and ME cells.

  4. Comparison of three types of chondrocytes in collagen scaffolds for cartilage tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Lu [Department of Plastic and Reconstructive Surgery, Shanghai Tissue Engineering Center, Shanghai 9th People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Spector, Myron, E-mail: luzhangmd@gmail.co [Tissue Engineering, VA Boston Healthcare System, Boston, MA (United States)

    2009-08-15

    The objective of this study was to compare the chondrogenesis in type I and II collagen scaffolds seeded with chondrocytes from three types of cartilage, after four weeks of culture: auricular (AU), articular (AR) and meniscal (ME). Related aims were to investigate the expression of a contractile muscle actin isoform, alpha-smooth muscle actin (SMA), in the cells in the scaffold and to determine the presence of a lubricating glycoprotein, lubricin, in the constructs. Adult goat AU, AR and ME chondrocytes were seeded into two types of collagen scaffolds: type II collagen and type I/III collagen. After four weeks of culture, the constructs were prepared for histochemical and immunohistochemical analysis of the distribution of glycosaminoglycan (GAG), types I and II collagen, elastin, SM and lubricin. AU constructs contained substantially more tissue than the AR and ME samples. The AU constructs exhibited neocartilage, but no elastin. There were no notable differences between the type I and II collagen scaffolds. Novel findings were the expression of SMA by the AU cells in the scaffolds and the presence of lubricin in the AR and AU constructs. AU cells have the capability to produce cartilage in collagen scaffolds under conditions in which there is little histogenesis by AR and ME cells.

  5. Collagen type IV at the fetal-maternal interface.

    Science.gov (United States)

    Oefner, C M; Sharkey, A; Gardner, L; Critchley, H; Oyen, M; Moffett, A

    2015-01-01

    Extracellular matrix proteins play a crucial role in influencing the invasion of trophoblast cells. However the role of collagens and collagen type IV (col-IV) in particular at the implantation site is not clear. Immunohistochemistry was used to determine the distribution of collagen types I, III, IV and VI in endometrium and decidua during the menstrual cycle and the first trimester of pregnancy. Expression of col-IV alpha chains during the reproductive cycle was determined by qPCR and protein localisation by immunohistochemistry. The structure of col-IV in placenta was examined using transmission electron microscopy. Finally, the expression of col-IV alpha chain NC1 domains and collagen receptors was localised by immunohistochemistry. Col-IV alpha chains were selectively up-regulated during the menstrual cycle and decidualisation. Primary extravillous trophoblast cells express collagen receptors and secrete col-IV in vitro and in vivo, resulting in the increased levels found in decidua basalis compared to decidua parietalis. A novel expression pattern of col-IV in the mesenchyme of placental villi, as a three-dimensional network, was found. NC1 domains of col-IV alpha chains are known to regulate tumour cell migration and the selective expression of these domains in decidua basalis compared to decidua parietalis was determined. Col-IV is expressed as novel forms in the placenta. These findings suggest that col-IV not only represents a structural protein providing tissue integrity but also influences the invasive behaviour of trophoblast cells at the implantation site. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Effects of joint immobilization on changes in myofibroblasts and collagen in the rat knee contracture model.

    Science.gov (United States)

    Sasabe, Ryo; Sakamoto, Junya; Goto, Kyo; Honda, Yuichiro; Kataoka, Hideki; Nakano, Jiro; Origuchi, Tomoki; Endo, Daisuke; Koji, Takehiko; Okita, Minoru

    2017-09-01

    The purpose of this study was to examine the time-dependent changes in the development of joint capsule fibrosis and in the number of myofibroblasts in the joint capsule after immobilization, using a rat knee contracture model. Both knee joints were fixed in full flexion for 1, 2, and 4 weeks (immobilization group). Untreated rats were bred for each immobilization period (control group). Histological analysis was performed to evaluate changes in the amount and density of collagen in the joint capsule. The changes in type I and III collagen mRNA were examined by in situ hybridization. The number of myofibroblasts in the joint capsule was assessed by immunohistochemical methods. In the immobilization group, the amount of collagen increased within 1 week and the density of collagen increased within 2 weeks, as compared with that in the control group. Type I collagen mRNA-positive cell numbers in the immobilization group increased at all time points. However, type III collagen mRNA-positive cell numbers did not increase. Myofibroblasts in the immobilization group significantly increased compared with those in the control group at all time points, and they increased significantly with the period of immobilization. These results suggest that joint capsule fibrosis with overexpression of type I collagen occurs and progresses within 1 week after immobilization, and an increase in myofibroblasts is related to the mechanism of joint capsule fibrosis. The findings suggest the need for a treatment targeting accumulation of type I collagen associated with an increase in myofibroblasts. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1998-2006, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  7. Collagens--structure, function, and biosynthesis.

    Science.gov (United States)

    Gelse, K; Pöschl, E; Aigner, T

    2003-11-28

    The extracellular matrix represents a complex alloy of variable members of diverse protein families defining structural integrity and various physiological functions. The most abundant family is the collagens with more than 20 different collagen types identified so far. Collagens are centrally involved in the formation of fibrillar and microfibrillar networks of the extracellular matrix, basement membranes as well as other structures of the extracellular matrix. This review focuses on the distribution and function of various collagen types in different tissues. It introduces their basic structural subunits and points out major steps in the biosynthesis and supramolecular processing of fibrillar collagens as prototypical members of this protein family. A final outlook indicates the importance of different collagen types not only for the understanding of collagen-related diseases, but also as a basis for the therapeutical use of members of this protein family discussed in other chapters of this issue.

  8. Quantification in immunohistochemistry: the measurement of the ratios of collagen types I and II

    NARCIS (Netherlands)

    van der Loos, C. M.; Marijianowski, M. M.; Becker, A. E.

    1994-01-01

    Quantitative techniques in immunohistochemistry are needed, but they are rarely applied because of doubtful reproducibility. We have developed a method for the detection of collagen types I and III in situ. The method applied was a two-step immuno-alkaline phosphatase technique with visualization of

  9. Collagen cross linking: Current perspectives

    Directory of Open Access Journals (Sweden)

    Srinivas K Rao

    2013-01-01

    Full Text Available Keratoconus is a common ectatic disorder occurring in more than 1 in 1,000 individuals. The condition typically starts in adolescence and early adulthood. It is a disease with an uncertain cause and its progression is unpredictable, but in extreme cases, vision deteriorates and can require corneal transplant surgery. Corneal collagen cross-linking (CCL with riboflavin (C3R is a recent treatment option that can enhance the rigidity of the cornea and prevent disease progression. Since its inception, the procedure has evolved with newer instrumentation, surgical techniques, and is also now performed for expanded indications other than keratoconus. With increasing experience, newer guidelines regarding optimization of patient selection, the spectrum of complications and their management, and combination procedures are being described. This article in conjunction with the others in this issue, will try and explore the uses of collagen cross-linking (CXL in its current form.

  10. Type I and III procollagen propeptides in growth hormone-deficient patients: effects of increasing doses of GH

    DEFF Research Database (Denmark)

    Jensen, L T; Jørgensen, J O; Risteli, J

    1991-01-01

    The effect of increasing doses of growth hormone on collagen synthesis in GH-treated GH-deficient patients was determined in a short-term study. The synthesis of type I and III collagen was estimated by measurements of the carboxyterminal propeptide of type I procollagen and the aminoterminal...... procollagen propeptide increased twice as much as type I procollagen propeptide, by 47 vs 25%, at a GH dose of 6 IU/day compared with 2 IU/day. The differences between the effects on type I and type III collagen may reflect differences in secretion or turn-over rate of collagen in bone and loose connective...

  11. Biomarkers of the extracellular matrix and of collagen fragments.

    Science.gov (United States)

    Chalikias, Georgios K; Tziakas, Dimitrios N

    2015-03-30

    A great body of evidence has shown that extracellular matrix (ECM) alterations are present in the major types of cardiac diseases: ischemic heart disease, heart disease associated with pressure overload, heart disease associated with volume overload, and intrinsic myocardial disease or cardiomyopathy. Collagen, type I and III, is the principal structural protein found in the myocardium and its pro- or telopeptides are released into the circulation during the course of cardiovascular diseases. Therefore, these peptides may reflect collagen synthesis and break-down and also represent a much more useful tool to address ECM changes from a distance. Clinical trials have been performed during recent years to examine the usage of these peptides as diagnostic or prognostic biomarkers in heart failure (HF) patients. This review aims to summarize published data concerning cardiac ECM and its circulating biomarkers. Studies that focused on collagen metabolism related biomarkers in patients with HF are analyzed. Finally, limitations associated with the clinical use of the aforementioned biomarkers are also discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Dextran derivatives modulate collagen matrix organization in dermal equivalent.

    Science.gov (United States)

    Frank, Laetitia; Lebreton-Decoster, Corinne; Godeau, Gaston; Coulomb, Bernard; Jozefonvicz, Jacqueline

    2006-01-01

    Dextran derivatives can protect heparin binding growth factor implied in wound healing, such as transforming growth factor-beta1 (TGF-beta1) and fibroblast growth factor-2 (FGF-2). The first aim of this study was to investigate the effect of these compounds on human dermal fibroblasts in culture with or without TGF-beta1. Several dextran derivatives obtained by substitution of methylcarboxylate (MC), benzylamide (B) and sulphate (Su) groups were used to determine the effects of each compound on fibroblast growth in vitro. The data indicate that sulphate groups are essential to act on the fibroblast proliferation. The dextran derivative LS21 DMCBSu has been chosen to investigate its effect on dermal wound healing process. Fibroblasts cultured in collagenous matrices named dermal equivalent were treated with the bioactive polymer alone or associated to TGF-beta1 or FGF-2. Cross-sections of dermal equivalent observed by histology or immunohistochemistry, demonstrated that the bioactive polymer accelerates the collagen matrices organization and stimulates the human type-III collagen expression. This bioactive polymer induces apoptosis of myofibroblast, property which may be beneficial in treatment of hypertrophic scar. Culture media analyzed by zymography and Western blot showed that this polymer significantly increases the secretion of zymogen and active form of matrix metalloproteinase-2 (MMP-2), involved in granulation tissue formation. These data suggest that this bioactive polymer has properties which may be beneficial in the treatment of wound healing.

  13. Collagen fibrillogenesis: fibronectin, integrins, and minor collagens as organizers and nucleators.

    Science.gov (United States)

    Kadler, Karl E; Hill, Adele; Canty-Laird, Elizabeth G

    2008-10-01

    Collagens are triple helical proteins that occur in the extracellular matrix (ECM) and at the cell-ECM interface. There are more than 30 collagens and collagen-related proteins but the most abundant are collagens I and II that exist as D-periodic (where D = 67 nm) fibrils. The fibrils are of broad biomedical importance and have central roles in embryogenesis, arthritis, tissue repair, fibrosis, tumor invasion, and cardiovascular disease. Collagens I and II spontaneously form fibrils in vitro, which shows that collagen fibrillogenesis is a selfassembly process. However, the situation in vivo is not that simple; collagen I-containing fibrils do not form in the absence of fibronectin, fibronectin-binding and collagen-binding integrins, and collagen V. Likewise, the thin collagen II-containing fibrils in cartilage do not form in the absence of collagen XI. Thus, in vivo, cellular mechanisms are in place to control what is otherwise a protein self-assembly process. This review puts forward a working hypothesis for how fibronectin and integrins (the organizers) determine the site of fibril assembly, and collagens V and XI (the nucleators) initiate collagen fibrillogenesis.

  14. Association of altered collagen content and lysyl oxidase expression in degenerative mitral valve disease.

    Science.gov (United States)

    Purushothaman, K-Raman; Purushothaman, Meerarani; Turnbull, Irene C; Adams, David H; Anyanwu, Anelechi; Krishnan, Prakash; Kini, Annapoorna; Sharma, Samin K; O'Connor, William N; Moreno, Pedro R

    Collagen cross-linking is mediated by lysyl oxidase (LOX) enzyme in the extracellular matrix (ECM) of mitral valve leaflets. Alterations in collagen content and LOX protein expression in the ECM of degenerative mitral valve may enhance leaflet expansion and disease severity. Twenty posterior degenerative mitral valve leaflets from patients with severe mitral regurgitation were obtained at surgery. Five normal posterior mitral valve leaflets procured during autopsy served as controls. Valvular interstitial cells (VICs) density was quantified by immunohistochemistry, collagen Types I and III by picro-sirius red staining and immunohistochemistry, and proteoglycans by alcian blue staining. Protein expression of LOX and its mediator TGFβ1 were quantified by immunofluorescence and gene expression by PCR. VIC density was increased, structural Type I collagen density was reduced, while reparative Type III collagen and proteoglycan densities were increased (PDegenerative Mitral Valve Disease may be secondary to alterations in LOX protein expression, contributing to disorganization of ECM and disease severity. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Complete Histological Resolution of Collagenous Sprue

    Directory of Open Access Journals (Sweden)

    Hugh J Freeman

    2004-01-01

    Full Text Available A 65-year-old woman developed a watery diarrhea syndrome with collagenous colitis. Later, weight loss and hypoalbuminemia were documented. This prompted small bowel biopsies that showed pathological changes of collagenous sprue. An apparent treatment response to a gluten-free diet and prednisone resulted in reduced diarrhea, weight gain and normalization of serum albumin. Later repeated biopsies from multiple small and large bowel sites over a period of over three years, however, showed reversion to normal small intestinal mucosa but persistent collagenous colitis. These results indicate that collagenous inflammatory disease may be a far more extensive process in the gastrointestinal tract than is currently appreciated. Moreover, collagenous colitis may be a clinical signal that occult small intestinal disease is present. Finally, collagenous sprue may, in some instances, be a completely reversible small intestinal disorder.

  16. A novel functional role of collagen glycosylation

    DEFF Research Database (Denmark)

    Jürgensen, Henrik J; Madsen, Daniel H; Ingvarsen, Signe

    2011-01-01

    Collagens make up the most abundant component of interstitial extracellular matrices and basement membranes. Collagen remodeling is a crucial process in many normal physiological events and in several pathological conditions. Some collagen subtypes contain specific carbohydrate side chains......, the function of which is poorly known. The endocytic collagen receptor urokinase plasminogen activator receptor-associated protein (uPARAP)/Endo180 plays an important role in matrix remodeling through its ability to internalize collagen for lysosomal degradation. uPARAP/Endo180 is a member of the mannose...... receptor protein family. These proteins all include a fibronectin type II domain and a series of C-type lectin-like domains, of which only a minor part possess carbohydrate recognition activity. At least two of the family members, uPARAP/Endo180 and the mannose receptor, interact with collagens...

  17. Effect of radiation on rat skin collagen

    International Nuclear Information System (INIS)

    Nogami, Akira

    1980-01-01

    I. Albino male rats were exposed for 16 weeks to ultraviolet light (UVL) which has principle emission at 305 nm. There were no significant changes between control and UVL-exposed skins in the total hydroxyproline content. However, a little increase of citrate-soluble collagen, a little decrease of insoluble collagen and a decrease of aldehyde content in soluble collagen were observed with UVL exposure. Total acid glycosaminoglycan in skin increased 30% or more from control. These results show that the effect of UVL on rat skin in vivo was merely inflammation phenomenon and that the 'aging' process of skin was not caused in our experimental conditions. II. The effects of radiation on the solubility of rat skin collagen were examined under various conditions. 1) When intact rats were exposed to a single dose of radiation from 43 kVp X-ray source, the solubility in skin collagen did not change at 4,000 R dosage, while in irradiation of 40,000 R a decreased solubility in collagen was observed. When rats were given 400 R a week for 12 weeks, there was no changes in the solubility of collagen during experimental period. 2) In vitro exposure to skins, an irradiation of 40,000 R from 43 kVp X-ray source caused a decrease in the solubility of collagen. While an irradiation of 40,000 R of dosage from 200 kVp X-ray source resulted in the increase in soluble collagen and the decrease in insoluble collagen. 3) When intact rats were given a single dose of 40,000 R from 60 Co- gamma -ray, insoluble collagen decreased in both young and adult rats. Similar changes in collagen solubility were observed in vitro gamma -irradiation. (author)

  18. Alginate-Collagen Fibril Composite Hydrogel

    Directory of Open Access Journals (Sweden)

    Mahmoud Baniasadi

    2015-02-01

    Full Text Available We report on the synthesis and the mechanical characterization of an alginate-collagen fibril composite hydrogel. Native type I collagen fibrils were used to synthesize the fibrous composite hydrogel. We characterized the mechanical properties of the fabricated fibrous hydrogel using tensile testing; rheometry and atomic force microscope (AFM-based nanoindentation experiments. The results show that addition of type I collagen fibrils improves the rheological and indentation properties of the hydrogel.

  19. Age-related collagen turnover of the interstitial matrix and basement membrane: Implications of age- and sex-dependent remodeling of the extracellular matrix.

    Science.gov (United States)

    Kehlet, Stephanie N; Willumsen, Nicholas; Armbrecht, Gabriele; Dietzel, Roswitha; Brix, Susanne; Henriksen, Kim; Karsdal, Morten A

    2018-01-01

    The extracellular matrix (ECM) plays a vital role in maintaining normal tissue function. Collagens are major components of the ECM and there is a tight equilibrium between degradation and formation of these proteins ensuring tissue health and homeostasis. As a consequence of tissue turnover, small collagen fragments are released into the circulation, which act as important biomarkers in the study of certain tissue-related remodeling factors in health and disease. The aim of this study was to establish an age-related collagen turnover profile of the main collagens of the interstitial matrix (type I and III collagen) and basement membrane (type IV collagen) in healthy men and women. By using well-characterized competitive ELISA-assays, we assessed specific fragments of degraded (C1M, C3M, C4M) and formed (PINP, Pro-C3, P4NP7S) type I, III and IV collagen in serum from 617 healthy men and women ranging in ages from 22 to 86. Subjects were divided into 5-year age groups according to their sex and age. Groups were compared using Kruskal-Wallis adjusted for Dunn's multiple comparisons test and Mann-Whitney t-test. Age-specific changes in collagen turnover was most profound for type I collagen. PINP levels decreased in men with advancing age, whereas in women, the level decreased in early adulthood followed by an increase around the age of menopause (age 40-60). Sex-specific changes in type I, III and IV collagen turnover was present at the age around menopause (age 40-60) with women having an increased turnover. In summary, collagen turnover is affected by age and sex with the interstitial matrix and the basement membrane being differently regulated. The observed changes needs to be accounted for when measuring ECM related biomarkers in clinical studies.

  20. Routes towards Novel Collagen-Like Biomaterials

    Directory of Open Access Journals (Sweden)

    Adrian V. Golser

    2018-04-01

    Full Text Available Collagen plays a major role in providing mechanical support within the extracellular matrix and thus has long been used for various biomedical purposes. Exemplary, it is able to replace damaged tissues without causing adverse reactions in the receiving patient. Today’s collagen grafts mostly are made of decellularized and otherwise processed animal tissue and therefore carry the risk of unwanted side effects and limited mechanical strength, which makes them unsuitable for some applications e.g., within tissue engineering. In order to improve collagen-based biomaterials, recent advances have been made to process soluble collagen through nature-inspired silk-like spinning processes and to overcome the difficulties in providing adequate amounts of source material by manufacturing collagen-like proteins through biotechnological methods and peptide synthesis. Since these methods also open up possibilities to incorporate additional functional domains into the collagen, we discuss one of the best-performing collagen-like type of proteins, which already have additional functional domains in the natural blueprint, the marine mussel byssus collagens, providing inspiration for novel biomaterials based on collagen-silk hybrid proteins.

  1. High resolution imaging of collagen organisation and synthesis using a versatile collagen specific probe

    NARCIS (Netherlands)

    Boerboom, R.A.; Krahn - Nash, K.; Megens, R.T.A.; Zandvoort, van M.; Merkx, M.; Bouten, C.V.C.

    2007-01-01

    Collagen is the protein primarily responsible for the load-bearing properties of tissues and collagen architecture is one of the main determinants of the mechanical properties of tissues. Visualisation of changes in collagen three-dimensional structure is essential in order to improve our

  2. Calcium hydroxylapatite treatment of human skin: evidence of collagen turnover through picrosirius red staining and circularly polarized microscopy

    Directory of Open Access Journals (Sweden)

    Zerbinati N

    2018-01-01

    Full Text Available Nicola Zerbinati,1 Alberto Calligaro2 1Department of Surgical and Morphological Sciences, University of Insubria (Varese and Polyspecialist Medical Center, Pavia, 2Department of Public Health, Experimental and Forensic Medicine, Unit of Histology and Embryology, University of Pavia, Pavia, Italy Background: Calcium hydroxylapatite (CaHA, Radiesse® is a biocompatible, injectable filler for facial soft-tissue augmentation that provides volume to tissues, followed by a process of neocollagenesis for improved skin quality. Objective: To examine the effects of CaHA treatment on the molecular organization of collagen using a combination of picrosirius red staining and circularly polarized light microscopy.Methods: Five subjects received subdermal injection of 0.3 mL of CaHA in tissues scheduled for removal during abdominoplasty 2 months later. Tissue specimens from the CaHA injection site and a control untreated area were obtained from excised skin at the time of surgery. Processed tissue sections were stained with picrosirius red solution 0.1% and visualized under circularly polarized light microscopy for identification of thick mature (type I and thin newly formed (type III collagen fibers. Pixel signals from both the control and CaHA-treated areas were extracted from the images, and morphometric computerized hue analysis was performed to provide a quantitative evaluation of mature and newly formed collagen fibers.Results: Under picrosirius red staining and circularly polarized light microscopy, green/yellow areas (thin newly formed collagen type III were visible among the collagen fibers in tissue sections from the area of CaHA injection. In contrast, the majority of the collagen fibers appeared red (thick mature collagen type I in control tissues. Morphometric analysis confirmed that, following CaHA treatment, the proportion of fibers represented by thin newly formed collagen type III increased significantly (p<0.01 in comparison with the

  3. Laser welding and collagen crosslinks

    Energy Technology Data Exchange (ETDEWEB)

    Reiser, K.M.; Last, J.A. [California Univ., Davis, CA (United States). Dept. of Medicine; Small, W. IV; Maitland, D.J.; Heredia, N.J.; Da Silva, L.B.; Matthews, D.L. [Lawrence Livermore National Lab., CA (United States)

    1997-02-20

    Strength and stability of laser-welded tissue may be influenced, in part, by effects of laser exposure on collagen crosslinking. We therefore studied effects of diode laser exposure (805 nm, 1-8 watts, 30 seconds) + indocyanine green dye (ICG) on calf tail tendon collagen crosslinks. Effect of ICG dye alone on crosslink content prior to laser exposure was investigated; unexpectedly, we found that ICG-treated tissue had significantly increased DHLNL and OHP, but not HLNL. Laser exposure after ICG application reduced elevated DHLNL and OHP crosslink content down to their native levels. The monohydroxylated crosslink HLNL was inversely correlated with laser output (p<0.01 by linear regression analysis). DHLNL content was highly correlated with content of its maturational product, OHP, suggesting that precursor-product relations are maintained. We conclude that: (1)ICG alone induces DHLNL and OHP crosslink formation; (2)subsequent laser exposure reduces the ICG-induced crosslinks down to native levels; (3)excessive diode laser exposure destroys normally occurring HLNL crosslinks.

  4. Expression of collagen and related growth factors in rat tendon and skeletal muscle in response to specific contraction types.

    Science.gov (United States)

    Heinemeier, K M; Olesen, J L; Haddad, F; Langberg, H; Kjaer, M; Baldwin, K M; Schjerling, P

    2007-08-01

    Acute exercise induces collagen synthesis in both tendon and muscle, indicating an adaptive response in the connective tissue of the muscle-tendon unit. However, the mechanisms of this adaptation, potentially involving collagen-inducing growth factors (such as transforming growth factor-beta-1 (TGF-beta-1)), as well as enzymes related to collagen processing, are not clear. Furthermore, possible differential effects of specific contraction types on collagen regulation have not been investigated. Female Sprague-Dawley rats were subjected to 4 days of concentric, eccentric or isometric training (n = 7-9 per group) of the medial gastrocnemius, by stimulation of the sciatic nerve. RNA was extracted from medial gastrocnemius and Achilles tendon tissue 24 h after the last training bout, and mRNA levels for collagens I and III, TGF-beta-1, connective tissue growth factor (CTGF), lysyl oxidase (LOX), metalloproteinases (MMP-2 and -9) and their inhibitors (TIMP-1 and 2) were measured by Northern blotting and/or real-time PCR. In tendon, expression of TGF-beta-1 and collagens I and III (but not CTGF) increased in response to all types of training. Similarly, enzymes/factors involved in collagen processing were induced in tendon, especially LOX (up to 37-fold), which could indicate a loading-induced increase in cross-linking of tendon collagen. In skeletal muscle, a similar regulation of gene expression was observed, but in contrast to the tendon response, the effect of eccentric training was significantly greater than the effect of concentric training on the expression of several transcripts. In conclusion, the study supports an involvement of TGF-beta-1 in loading-induced collagen synthesis in the muscle-tendon unit and importantly, it indicates that muscle tissue is more sensitive than tendon to the specific mechanical stimulus.

  5. Modern collagen wound dressings: function and purpose.

    Science.gov (United States)

    Fleck, Cynthia Ann; Simman, Richard

    2010-09-01

    Collagen, which is produced by fibroblasts, is the most abundant protein in the human body. A natural structural protein, collagen is involved in all 3 phases of the wound-healing cascade. It stimulates cellular migration and contributes to new tissue development. Because of their chemotactic properties on wound fibroblasts, collagen dressings encourage the deposition and organization of newly formed collagen, creating an environment that fosters healing. Collagen-based biomaterials stimulate and recruit specific cells, such as macrophages and fibroblasts, along the healing cascade to enhance and influence wound healing. These biomaterials can provide moisture or absorption, depending on the delivery system. Collagen dressings are easy to apply and remove and are conformable. Collagen dressings are usually formulated with bovine, avian, or porcine collagen. Oxidized regenerated cellulose, a plant-based material, has been combined with collagen to produce a dressing capable of binding to and protecting growth factors by binding and inactivating matrix metalloproteinases in the wound environment. The increased understanding of the biochemical processes involved in chronic wound healing allows the design of wound care products aimed at correcting imbalances in the wound microenvironment. Traditional advanced wound care products tend to address the wound's macroenvironment, including moist wound environment control, fluid management, and controlled transpiration of wound fluids. The newer class of biomaterials and wound-healing agents, such as collagen and growth factors, targets specific defects in the chronic wound environment. In vitro laboratory data point to the possibility that these agents benefit the wound healing process at a biochemical level. Considerable evidence has indicated that collagen-based dressings may be capable of stimulating healing by manipulating wound biochemistry.

  6. Influence of suture on peripheral nerve regeneration and collagen production at the site of neurorrhaphy: an experimental study.

    Science.gov (United States)

    Martins, Roberto Sergio; Teodoro, Walcy Rosolio; Simplicio, Hougelle; Capellozi, Vera Luiza; Siqueira, Mario Gilberto; Yoshinari, Natalino Hajime; Pereira, José Pindaro; Teixeira, Manoel Jacobsen

    2011-03-01

    Restoration of nerve continuity and effective maintenance of coaptation are considered fundamental principles of end-to-end peripheral nerve repair. To evaluate the influence of the number of stitches on axonal regeneration and collagen production after neurorrhaphy. Thirty male Wistar rats were equally divided into 3 groups and were all operated on with the right sciatic nerve exposed. In 2 groups, the nerve was sectioned and repaired by means of 3 (group B) or 6 (group C) epineurium sutures with 10-0 monofilament nylon. One group (group A) was used as a control. Each animal from groups B and C underwent electrophysiological evaluation with motor action potential recordings before nerve section and again at an 8-week interval after neurorrhaphy. Nerve biopsy specimens were used for histomorphometric assessment of axonal regeneration and quantification of collagen at the repair site. Animals from group C had significantly lower motor action potential conduction velocities compared with control animals (P=.02), and no significant difference was seen between groups B and C. Parameters obtained from morphometric evaluation were not significantly different between these 2 groups. Type I collagen and III collagen in the epineurium were significantly higher in group C than in either the control group (P=.001 and P=.003) or group B (P=.01 and P=.02). No differences were identified for collagen I and III in the endoneurium. Using 6 sutures for nerve repair is associated with worse electrophysiological outcomes and higher amounts of type I and III collagen in the epineurium compared with control. Neurorraphy with 6 stitches is also related to a significant increase in epineurium collagen I and III compared with 3-stitch neurorraphy. Copyright (C) by the Congress of Neurological Surgeons

  7. Richard III

    DEFF Research Database (Denmark)

    Lauridsen, Palle Schantz

    2017-01-01

    Kort analyse af Shakespeares Richard III med fokus på, hvordan denne skurk fremstilles, så tilskuere (og læsere) langt henad vejen kan føle sympati med ham. Med paralleller til Netflix-serien "House of Cards"......Kort analyse af Shakespeares Richard III med fokus på, hvordan denne skurk fremstilles, så tilskuere (og læsere) langt henad vejen kan føle sympati med ham. Med paralleller til Netflix-serien "House of Cards"...

  8. Recombinant gelatin and collagen from methylotrophic yeasts

    NARCIS (Netherlands)

    Bruin, de E.C.

    2002-01-01

    Based on its structural role and compatibility within the human body, collagen is a commonly used biomaterial in medical applications, such as cosmetic surgery, wound treatment and tissue engineering. Gelatin is in essence denatured and partly degraded collagen and is,

  9. Biomimetic soluble collagen purified from bones.

    Science.gov (United States)

    Ferreira, Ana Marina; Gentile, Piergiorgio; Sartori, Susanna; Pagliano, Cristina; Cabrele, Chiara; Chiono, Valeria; Ciardelli, Gianluca

    2012-11-01

    Type I collagen has been extensively exploited as a biomaterial for biomedical applications and drug delivery; however, small molecular alterations occurring during the isolation procedure and its interaction with residual bone extracellular matrix molecules or proteins might affect the overall material biocompatibility and performance. The aim of the current work is to study the potential alterations in collagen properties and organization associated with the absence of proteoglycans, which mimic pathological conditions associated with age-related diseases. A new approach for evaluating the effect of proteoglycans on the properties of isolated type I collagen from the bone matrix is described. Additional treatment with guanidine hydrochloride was introduced to remove residual proteoglycans from the collagen matrix. The properties of the isolated collagen with/without guanidine hydrochloride treatment were investigated and compared with a commercial rabbit collagen as control. We demonstrate that the absence of proteoglycans in the isolated type I collagen affects its thermal properties, the extraction into its native structure, and its ability to hydrate and self-assemble into fibers. The fine control and tuning of all these features, linked to the absence of non-collagenous proteins as proteoglycans, offer the possibility of designing new strategies and biomaterials with advanced biomimetic properties aimed at regenerating bone tissue in the case of fragility and/or defects. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Chondroitin Sulfate Perlecan Enhances Collagen Fibril Formation

    DEFF Research Database (Denmark)

    Kvist, A. J.; Johnson, A. E.; Mörgelin, M.

    2006-01-01

    in collagen type II fibril assembly by perlecan-null chondrocytes. Cartilage perlecan is a heparin sulfate or a mixed heparan sulfate/chondroitin sulfate proteoglycan. The latter form binds collagen and accelerates fibril formation in vitro, with more defined fibril morphology and increased fibril diameters...... produced in the presence of perlecan. Interestingly, the enhancement of collagen fibril formation is independent on the core protein and is mimicked by chondroitin sulfate E but neither by chondroitin sulfate D nor dextran sulfate. Furthermore, perlecan chondroitin sulfate contains the 4,6-disulfated...... disaccharides typical for chondroitin sulfate E. Indeed, purified glycosaminoglycans from perlecan-enriched fractions of cartilage extracts contain elevated levels of 4,6-disulfated chondroitin sulfate disaccharides and enhance collagen fibril formation. The effect on collagen assembly is proportional...

  11. PARDISEKO III

    International Nuclear Information System (INIS)

    Jordan, H.; Sack, C.

    1975-05-01

    This report gives a detailed description of the latest version of the PARDISEKO code, PARDISEKO III, with particular emphasis on the numerical and programming methods employed. The physical model and its relation to nuclear safety as well as a description and the results of confirming experiments are treated in detail in the Karlsruhe Nuclear Research Centre report KFK-1989. (orig.) [de

  12. Biosynthesis of collagen in the lung of the mouse after X-irradiation

    International Nuclear Information System (INIS)

    Walklin, C.M.; Law, M.P.

    1986-01-01

    Increases in the activities of both prolyl-4-hydroxylase (P-4-Hase) and protein disulphide isomerase (PDI) were observed as early as 1 month after 5-9 Gy. Maximal increases were observed at 6-7 months after 9 Gy and persisted up to 15 months after exposure. Increases after 5 and 7.5 Gy were more gradual but by 1 year after irradiation they had reached levels similar to those after 9 Gy. Collagen types were analysed at 2, 7.5 and 15 months. Results are shown for 7.5 and 15 months after 9 Gy. Although the total collagen content was increased, the ratio of collagen type I to III was normal. (UK)

  13. Non-invasive quantification of collagen turnover in renal transplant recipients

    DEFF Research Database (Denmark)

    Stribos, Elisabeth G D; Nielsen, Signe Holm; Pedersen, Susanne Brix

    2017-01-01

    in RTR. Seventy-eight patients who attended the University Medical Center Groningen for a routine check-up after kidney transplantation were enrolled in the study. Plasma and/or 24h-urine samples were collected and specific matrix-metalloproteinase-generated neo-epitope fragments of collagens were...... measured by enzyme-linked immunosorbent assay. Our results demonstrated that urinary levels of C3M, a marker for collagen type III degradation, correlated with estimated glomerular filtration rate (eGFR; r = 0.58, p..., plasma levels of Pro-C6, a marker for collagen type VI formation, significantly increased with disease progression and correlated with eGFR (r = -0.72, p

  14. The Prognostic and Predictive Value of Soluble Type IV Collagen in Colorectal Cancer

    DEFF Research Database (Denmark)

    Rolff, Hans Christian; Christensen, Ib Jarle; Vainer, Ben

    2016-01-01

    PURPOSE: To investigate the prognostic and predictive biomarker value of type IV collagen in colorectal cancer. EXPERIMENTAL DESIGN: Retrospective evaluation of two independent cohorts of patients with colorectal cancer included prospectively in 2004-2005 (training set) and 2006-2008 (validation....... RESULTS: High levels of type IV collagen showed independent prognostic significance in both cohorts with hazard ratios (HRs; for a one-unit change on the log base 2 scale) of 2.25 [95% confidence intervals (CIs), 1.78-2.84; P ... and validation set, respectively. The prognostic impact was present both in patients with metastatic and nonmetastatic disease. The predictive value of the marker was investigated in stage II and III patients. In the training set, type IV collagen was prognostic both in the subsets of patients receiving...

  15. Natural history of markers of collagen turnover in patients with early diastolic dysfunction and impact of eplerenone.

    LENUS (Irish Health Repository)

    Mak, George J

    2012-02-01

    OBJECTIVES: This study was designed to evaluate the impact of eplerenone on collagen turnover in preserved systolic function heart failure (HFPSF). BACKGROUND: Despite growing interest in abnormal collagen metabolism as a feature of HFPSF with diastolic dysfunction, the natural history of markers of collagen turnover and the impact of selective aldosterone antagonism on this natural history remains unknown. METHODS: We evaluated 44 patients with HFPSF, randomly assigned to control (n = 20) or eplerenone 25 mg daily (n = 24) for 6 months, increased to 50 mg daily from 6 to 12 months. Serum markers of collagen turnover and inflammation were analyzed at baseline and at 6 and 12 months and included pro-collagen type-I and -III aminoterminal peptides, matrix metalloproteinase type-2, interleukin-6 and -8, and tumor necrosis factor-alpha. Doppler-echocardiographic assessment of diastolic filling indexes and tissue Doppler analyses were also obtained. RESULTS: The mean age of the patients was 80 +\\/- 7.8 years; 46% were male; 64% were receiving an angiotensin-converting enzyme inhibitor, 34% an angiotensin-II receptor blocker, and 68% were receiving beta-blocker therapy. Pro-collagen type-III and -I aminoterminal peptides, matrix metalloproteinase type-2, interleukin-6 and -8, and tumor necrosis factor-alpha increased with time in the control group. Eplerenone treatment had no significant impact on any biomarker at 6 months but attenuated the increase in pro-collagen type-III aminoterminal peptide at 12 months (p = 0.006). Eplerenone therapy was associated with modest effects on diastolic function without any impact on clinical variables or brain natriuretic peptide. CONCLUSIONS: This study demonstrates progressive increases in markers of collagen turnover and inflammation in HFPSF with diastolic dysfunction. Despite high background utilization of renin-angiotensin-aldosterone modulators, eplerenone therapy prevents a progressive increase in pro-collagen type-III

  16. Accelerated collagen turnover in women with angina pectoris without obstructive coronary artery disease: An iPOWER substudy.

    Science.gov (United States)

    Nielsen, Signe H; Mygind, Naja D; Michelsen, Marie M; Bechsgaard, Daria F; Suhrs, Hannah E; Genovese, Federica; Nielsen, Henning B; Brix, Susanne; Karsdal, Morten; Prescott, Eva; Kastrup, Jens

    2018-05-01

    Aim Collagens are major cardiac extracellular matrix components, known to be actively remodelled and accumulated during diffuse myocardial fibrosis. We evaluated whether accelerated collagen turnover described by neo-epitope biomarkers reflecting collagen formation and degradation separates patients with diffuse myocardial fibrosis from asymptomatic controls. Methods and results Seventy-one women with angina pectoris without significant coronary artery disease assessed by invasive coronary angiogram were included. Competitive enzyme-linked immunosorbent assays (ELISAs) measuring circulating protein fragments in serum assessed the formation and degradation of collagen type III (Pro-C3, C3M and C3C), IV (P4NP7S and C4M), V (Pro-C5 and C5M) and VI (Pro-C6 and C6M), and degradation of collagen type I (C1M). Serum samples from 32 age-matched asymptomatic women were included as controls. Symptomatic women presented significantly elevated levels of Pro-C6, C3C, C3M, C4M and C8-C ( p angina pectoris, but without significant obstructive coronary artery disease, showed an imbalanced collagen turnover compared to asymptomatic controls. The examined biomarkers are tools to monitor active collagen remodelling in patients with angina pectoris, in risk of developing myocardial fibrosis.

  17. Nonlinear optical response of the collagen triple helix and second harmonic microscopy of collagen liquid crystals

    Science.gov (United States)

    Deniset-Besseau, A.; De Sa Peixoto, P.; Duboisset, J.; Loison, C.; Hache, F.; Benichou, E.; Brevet, P.-F.; Mosser, G.; Schanne-Klein, M.-C.

    2010-02-01

    Collagen is characterized by triple helical domains and plays a central role in the formation of fibrillar and microfibrillar networks, basement membranes, as well as other structures of the connective tissue. Remarkably, fibrillar collagen exhibits efficient Second Harmonic Generation (SHG) and SHG microscopy proved to be a sensitive tool to score fibrotic pathologies. However, the nonlinear optical response of fibrillar collagen is not fully characterized yet and quantitative data are required to further process SHG images. We therefore performed Hyper-Rayleigh Scattering (HRS) experiments and measured a second order hyperpolarisability of 1.25 10-27 esu for rat-tail type I collagen. This value is surprisingly large considering that collagen presents no strong harmonophore in its amino-acid sequence. In order to get insight into the physical origin of this nonlinear process, we performed HRS measurements after denaturation of the collagen triple helix and for a collagen-like short model peptide [(Pro-Pro-Gly)10]3. It showed that the collagen large nonlinear response originates in the tight alignment of a large number of weakly efficient harmonophores, presumably the peptide bonds, resulting in a coherent amplification of the nonlinear signal along the triple helix. To illustrate this mechanism, we successfully recorded SHG images in collagen liquid solutions by achieving liquid crystalline ordering of the collagen triple helices.

  18. The Mineral–Collagen Interface in Bone

    Science.gov (United States)

    2015-01-01

    The interface between collagen and the mineral reinforcement phase, carbonated hydroxyapatite (cAp), is essential for bone’s remarkable functionality as a biological composite material. The very small dimensions of the cAp phase and the disparate natures of the reinforcement and matrix are essential to the material’s performance but also complicate study of this interface. This article summarizes what is known about the cAp-collagen interface in bone and begins with descriptions of the matrix and reinforcement roles in composites, of the phases bounding the interface, of growth of cAp growing within the collagen matrix, and of the effect of intra- and extrafibrilar mineral on determinations of interfacial properties. Different observed interfacial interactions with cAp (collagen, water, non-collagenous proteins) are reviewed; experimental results on interface interactions during loading are reported as are their influence on macroscopic mechanical properties; conclusions of numerical modeling of interfacial interactions are also presented. The data suggest interfacial interlocking (bending of collagen molecules around cAp nanoplatelets) and water-mediated bonding between collagen and cAp are essential to load transfer. The review concludes with descriptions of areas where new research is needed to improve understanding of how the interface functions. PMID:25824581

  19. Age Increases Monocyte Adhesion on Collagen

    Science.gov (United States)

    Khalaji, Samira; Zondler, Lisa; Kleinjan, Fenneke; Nolte, Ulla; Mulaw, Medhanie A.; Danzer, Karin M.; Weishaupt, Jochen H.; Gottschalk, Kay-E.

    2017-05-01

    Adhesion of monocytes to micro-injuries on arterial walls is an important early step in the occurrence and development of degenerative atherosclerotic lesions. At these injuries, collagen is exposed to the blood stream. We are interested whether age influences monocyte adhesion to collagen under flow, and hence influences the susceptibility to arteriosclerotic lesions. Therefore, we studied adhesion and rolling of human peripheral blood monocytes from old and young individuals on collagen type I coated surface under shear flow. We find that firm adhesion of monocytes to collagen type I is elevated in old individuals. Pre-stimulation by lipopolysaccharide increases the firm adhesion of monocytes homogeneously in older individuals, but heterogeneously in young individuals. Blocking integrin αx showed that adhesion of monocytes to collagen type I is specific to the main collagen binding integrin αxβ2. Surprisingly, we find no significant age-dependent difference in gene expression of integrin αx or integrin β2. However, if all integrins are activated from the outside, no differences exist between the age groups. Altered integrin activation therefore causes the increased adhesion. Our results show that the basal increase in integrin activation in monocytes from old individuals increases monocyte adhesion to collagen and therefore the risk for arteriosclerotic plaques.

  20. Cosmetic Potential of Marine Fish Skin Collagen

    Directory of Open Access Journals (Sweden)

    Ana L. Alves

    2017-10-01

    Full Text Available Many cosmetic formulations have collagen as a major component because of its significant benefits as a natural humectant and moisturizer. This industry is constantly looking for innovative, sustainable, and truly efficacious products, so marine collagen based formulations are arising as promising alternatives. A solid description and characterization of this protein is fundamental to guarantee the highest quality of each batch. In the present study, we present an extensive characterization of marine-derived collagen extracted from salmon and codfish skins, targeting its inclusion as component in cosmetic formulations. Chemical and physical characterizations were performed using several techniques such as sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE, Fourier Transformation Infrared (FTIR spectroscopy rheology, circular dichroism, X-ray diffraction, humidity uptake, and a biological assessment of the extracts regarding their irritant potential. The results showed an isolation of type I collagen with high purity but with some structural and chemical differences between sources. Collagen demonstrated a good capacity to retain water, thus being suitable for dermal applications as a moisturizer. A topical exposure of collagen in a human reconstructed dermis, as well as the analysis of molecular markers for irritation and inflammation, exhibited no irritant potential. Thus, the isolation of collagen from fish skins for inclusion in dermocosmetic applications may constitute a sustainable and low-cost platform for the biotechnological valorization of fish by-products.

  1. Association of collagen architecture with glioblastoma patient survival.

    Science.gov (United States)

    Pointer, Kelli B; Clark, Paul A; Schroeder, Alexandra B; Salamat, M Shahriar; Eliceiri, Kevin W; Kuo, John S

    2017-06-01

    OBJECTIVE Glioblastoma (GBM) is the most malignant primary brain tumor. Collagen is present in low amounts in normal brain, but in GBMs, collagen gene expression is reportedly upregulated. However, to the authors' knowledge, direct visualization of collagen architecture has not been reported. The authors sought to perform the first direct visualization of GBM collagen architecture, identify clinically relevant collagen signatures, and link them to differential patient survival. METHODS Second-harmonic generation microscopy was used to detect collagen in a GBM patient tissue microarray. Focal and invasive GBM mouse xenografts were stained with Picrosirius red. Quantitation of collagen fibers was performed using custom software. Multivariate survival analysis was done to determine if collagen is a survival marker for patients. RESULTS In focal xenografts, collagen was observed at tumor brain boundaries. For invasive xenografts, collagen was intercalated with tumor cells. Quantitative analysis showed significant differences in collagen fibers for focal and invasive xenografts. The authors also found that GBM patients with more organized collagen had a longer median survival than those with less organized collagen. CONCLUSIONS Collagen architecture can be directly visualized and is different in focal versus invasive GBMs. The authors also demonstrate that collagen signature is associated with patient survival. These findings suggest that there are collagen differences in focal versus invasive GBMs and that collagen is a survival marker for GBM.

  2. Characterization of Genipin-Modified Dentin Collagen

    Directory of Open Access Journals (Sweden)

    Hiroko Nagaoka

    2014-01-01

    Full Text Available Application of biomodification techniques to dentin can improve its biochemical and biomechanical properties. Several collagen cross-linking agents have been reported to strengthen the mechanical properties of dentin. However, the characteristics of collagen that has undergone agent-induced biomodification are not well understood. The objective of this study was to analyze the effects of a natural cross-linking agent, genipin (GE, on dentin discoloration, collagen stability, and changes in amino acid composition and lysyl oxidase mediated natural collagen cross-links. Dentin collagen obtained from extracted bovine teeth was treated with three different concentrations of GE (0.01%, 0.1%, and 0.5% for several treatment times (0–24 h. Changes in biochemical properties of NaB3H4-reduced collagen were characterized by amino acid and cross-link analyses. The treatment of dentin collagen with GE resulted in a concentration- and time-dependent pigmentation and stability against bacterial collagenase. The lysyl oxidase-mediated trivalent mature cross-link, pyridinoline, showed no difference among all groups while the major divalent immature cross-link, dehydro-dihydroxylysinonorleucine/its ketoamine in collagen treated with 0.5% GE for 24 h, significantly decreased compared to control (P< 0.05. The newly formed GE-induced cross-links most likely involve lysine and hydroxylysine residues of collagen in a concentration-dependent manner. Some of these cross-links appear to be reducible and stabilized with NaB3H4.

  3. Fermilab III

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The total ongoing plans for Fermilab are wrapped up in the Fermilab III scheme, centrepiece of which is the proposal for a new Main Injector. The Laboratory has been awarded a $200,000 Illinois grant which will be used to initiate environmental assessment and engineering design of the Main Injector, while a state review panel recommended that the project should also benefit from $2 million of funding

  4. Fermilab III

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1990-09-15

    The total ongoing plans for Fermilab are wrapped up in the Fermilab III scheme, centrepiece of which is the proposal for a new Main Injector. The Laboratory has been awarded a $200,000 Illinois grant which will be used to initiate environmental assessment and engineering design of the Main Injector, while a state review panel recommended that the project should also benefit from $2 million of funding.

  5. Venemaa - lähedane ja kauge / David Vseviov

    Index Scriptorium Estoniae

    Vseviov, David, 1949-

    2007-01-01

    Rmt.: Sergejev, Vladimir ; Vseviov, David. Venemaa - lähedane ja kauge : aegade algusest kuni Vassili III-ni. Tallinn : Valgus, 2002 ; Sergejev, Vladimir ; Vseviov, David. Venemaa - lähedane ja kauge : vürstiriigist tsaaririigiks. Ivan IV. Tallinn : Valgus, 2007.

  6. Improvement of skin condition by oral administration of collagen hydrolysates in chronologically aged mice.

    Science.gov (United States)

    Wang, Zhenbin; Wang, Qing; Wang, Lin; Xu, Weidong; He, Yuanqing; Li, Yunliang; He, Song; Ma, Haile

    2017-07-01

    Collagen hydrolysates (CHs) have been demonstrated to have positive effects on skin photoaging by topical application or oral ingestion. However, there has been little research on their influence on skin chronological aging. In this study, 9-month-old female ICR mice were given normal AIN-93M diets containing CHs (2.5, 5 and 10% w/w) from Nile tilapia scale. After 6 months, the collagen content and antioxidant enzyme (superoxide dismutase and glutathione peroxidase) activities increased significantly (P skin did not change (P > 0.05). The color, luster and quantity of hair were obviously ameliorated. Moreover, the structure of epidermis and dermis, the density and distribution of collagen fibers and the ratio of type I to type III collagen were improved in a dose-dependent manner as shown by histochemical staining. Oral ingestion of CHs increased the collagen content and antioxidant enzyme activities and improved the appearance and structure of skin. These results suggest the potential of CHs as an anti-skin-aging ingredient in nutraceuticals or functional foods. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  7. Impaired intestinal wound healing in Fhl2-deficient mice is due to disturbed collagen metabolism

    International Nuclear Information System (INIS)

    Kirfel, Jutta; Pantelis, Dimitrios; Kabba, Mustapha; Kahl, Philip; Roeper, Anke; Kalff, Joerg C.; Buettner, Reinhard

    2008-01-01

    Four and one half LIM domain protein FHL2 participates in many cellular processes involved in tissue repair such as regulation of gene expression, cytoarchitecture, cell adhesion, migration and signal transduction. The repair process after wounding is initiated by the release of peptides and bioactive lipids. These molecules induce synthesis and deposition of a provisional extracellular matrix. We showed previously that sphingosine-1-phosphate (S1P) triggers a signal transduction cascade mediating nuclear translocation of FHL2 in response to activation of the RhoA GTPase. Our present study shows that FHL2 is an important signal transducer influencing the outcome of intestinal anastomotic healing. Early wound healing is accompanied by reconstitution and remodelling of the extracellular matrix and collagen is primarily responsible for wound strength. Our results show that impaired intestinal wound healing in Fhl2-deficient mice is due to disturbed collagen III metabolism. Impaired collagen III synthesis reduced the mechanical stability of the anastomoses and led to lower bursting pressure in Fhl2-deficient mice after surgery. Our data confirm that FHL2 is an important factor regulating collagen expression in the early phase of wound healing, and thereby is critically involved in the physiologic process of anastomosis healing after bowel surgery and thus may represent a new therapeutic target

  8. Extracellular matrix of smooth muscle cells: interaction of collagen type V with heparan sulfate proteoglycan

    International Nuclear Information System (INIS)

    Gay, S.; Hoeoek, M.; Gay, R.E.; Magargal, W.W.; Reynertson, R.H.

    1986-01-01

    Alteration in the extracellular matrix produced by smooth muscle cells may play a role in the development of atherosclerotic lesions. Consequently the authors have initiated studies on the structural organization of the extracellular matrix produced by cultured smooth muscle cells. Immunohisotological examination of this matrix using well-characterized mono- and polyclonal antibodies showed a partial codistribution of heparan sulfate (HS) proteoglycans with a number of different matrix components including collagen types I, III, IV, V and VI, laminin and fibronectin. Subsequent binding studies between isolated matrix proteins and HS showed that the polysaccharide interacts strongly with type V collagen and to a lesser extent with fibronectin as well as collagen types III and VI. The interaction between type V and HS was readily inhibited by heparin and highly sulfated HS but not be dermatan sulfate, chondroitin sulfate or HS with a low sulfate content. Furthermore, [ 35 S]-HS proteoglycans isolated from cultured smooth muscle cells could be adsorbed on a column of sepharose conjugated with native type V collagen and eluted in a salt gradient. Hence, the interaction between type V and HS may play a major part in stabilizing the extracellular matrix of the vessel wall

  9. Fibrous mini-collagens in hydra nematocysts.

    Science.gov (United States)

    Holstein, T W; Benoit, M; Herder, G V; David, C N; Wanner, G; Gaub, H E

    1994-07-15

    Nematocysts (cnidocysts) are exocytotic organelles found in all cnidarians. Here, atomic force microscopy and field emission scanning electron microscopy reveal the structure of the nematocyst capsule wall. The outer wall consists of globular proteins of unknown function. The inner wall consists of bundles of collagen-like fibrils having a spacing of 50 to 100 nanometers and cross-striations at intervals of 32 nanometers. The fibrils consist of polymers of "mini-collagens," which are abundant in the nematocysts of Hydra. The distinct pattern of mini-collagen fibers in the inner wall can provide the tensile strength necessary to withstand the high osmotic pressure (15 megapascals) in the capsules.

  10. Insights on the evolution of prolyl 3-hydroxylation sites from comparative analysis of chicken and Xenopus fibrillar collagens.

    Science.gov (United States)

    Hudson, David M; Weis, Maryann; Eyre, David R

    2011-05-03

    Recessive mutations that prevent 3-hydroxyproline formation in type I collagen have been shown to cause forms of osteogenesis imperfecta. In mammals, all A-clade collagen chains with a GPP sequence at the A1 site (P986), except α1(III), have 3Hyp at residue P986. Available avian, amphibian and reptilian type III collagen sequences from the genomic database (Ensembl) all differ in sequence motif from mammals at the A1 site. This suggests a potential evolutionary distinction in prolyl 3-hydroxylation between mammals and earlier vertebrates. Using peptide mass spectrometry, we confirmed that this 3Hyp site is fully occupied in α1(III) from an amphibian, Xenopus laevis, as it is in chicken. A thorough characterization of all predicted 3Hyp sites in collagen types I, II, III and V from chicken and xenopus revealed further differences in the pattern of occupancy of the A3 site (P707). In mammals only α2(I) and α2(V) chains had any 3Hyp at the A3 site, whereas in chicken all α-chains except α1(III) had A3 at least partially 3-hydroxylated. The A3 site was also partially 3-hydroxylated in xenopus α1(I). Minor differences in covalent cross-linking between chicken, xenopus and mammal type I and III collagens were also found as a potential index of evolving functional differences. The function of 3Hyp is still unknown but observed differences in site occupancy during vertebrate evolution are likely to give important clues.

  11. Insights on the evolution of prolyl 3-hydroxylation sites from comparative analysis of chicken and Xenopus fibrillar collagens.

    Directory of Open Access Journals (Sweden)

    David M Hudson

    2011-05-01

    Full Text Available Recessive mutations that prevent 3-hydroxyproline formation in type I collagen have been shown to cause forms of osteogenesis imperfecta. In mammals, all A-clade collagen chains with a GPP sequence at the A1 site (P986, except α1(III, have 3Hyp at residue P986. Available avian, amphibian and reptilian type III collagen sequences from the genomic database (Ensembl all differ in sequence motif from mammals at the A1 site. This suggests a potential evolutionary distinction in prolyl 3-hydroxylation between mammals and earlier vertebrates. Using peptide mass spectrometry, we confirmed that this 3Hyp site is fully occupied in α1(III from an amphibian, Xenopus laevis, as it is in chicken. A thorough characterization of all predicted 3Hyp sites in collagen types I, II, III and V from chicken and xenopus revealed further differences in the pattern of occupancy of the A3 site (P707. In mammals only α2(I and α2(V chains had any 3Hyp at the A3 site, whereas in chicken all α-chains except α1(III had A3 at least partially 3-hydroxylated. The A3 site was also partially 3-hydroxylated in xenopus α1(I. Minor differences in covalent cross-linking between chicken, xenopus and mammal type I and III collagens were also found as a potential index of evolving functional differences. The function of 3Hyp is still unknown but observed differences in site occupancy during vertebrate evolution are likely to give important clues.

  12. A New Kind of Biomaterials-Bullfrog Skin Collagen

    Institute of Scientific and Technical Information of China (English)

    He LI; Bai Ling LIU; Hua Lin CHEN; Li Zhen GAO

    2003-01-01

    Pepsin-soluble collagen was prepared from bullfrog skin and partially characterized. This study revealed interesting differences, such as molecular weight, amino acid composition, denaturation temperature (Td), in the frog skin collagen when compared to the known vertebrate collagens. This study gives hints that bullfrog skin can be a potential, safe alternative source of collagen from cattle for use in various fields.

  13. Protease-activatable collagen targeting based on protein cyclization

    NARCIS (Netherlands)

    Breurken, M.; Lempens, E.H.M.; Merkx, M.

    2010-01-01

    Threading collagen through a protein needle: The collagen-binding protein CNA35 operates by wrapping itself around the collagen triple helix. By connecting the N and C termini through an MMP recognition sequence, a dual-specific MMP-sensitive collagen-targeting ligand is obtained that can be used

  14. Collagen based Biomaterials from CLRI: An Inspiration from the ...

    Indian Academy of Sciences (India)

    Collagen-based Smart Biomaterials · Smart materials: As smart people see them · Some Biomaterials based on Collagen in Human Health care · Questions of Value to this presentation ... Collagen based biomaterials · COLLAGEN IN VISION CARE · Slide 57 · Bandage lens: A smart device · Work at CLRI: In summary.

  15. Effect of Vaginal or Systemic Estrogen on Dynamics of Collagen Assembly in the Rat Vaginal Wall1

    Science.gov (United States)

    Montoya, T. Ignacio; Maldonado, P. Antonio; Acevedo, Jesus F.; Word, R. Ann

    2014-01-01

    ABSTRACT The objective of this study was to compare the effects of systemic and local estrogen treatment on collagen assembly and biomechanical properties of the vaginal wall. Ovariectomized nulliparous rats were treated with estradiol or conjugated equine estrogens (CEEs) either systemically, vaginal CEE, or vaginal placebo cream for 4 wk. Low-dose local CEE treatment resulted in increased vaginal epithelial thickness and significant vaginal growth without uterine hyperplasia. Furthermore, vaginal wall distensibility increased without compromise of maximal force at failure. Systemic estradiol resulted in modest increases in collagen type I with no change in collagen type III mRNA. Low-dose vaginal treatment, however, resulted in dramatic increases in both collagen subtypes whereas moderate and high dose local therapies were less effective. Consistent with the mRNA results, low-dose vaginal estrogen resulted in increased total and cross-linked collagen content. The inverse relationship between vaginal dose and collagen expression may be explained in part by progressive downregulation of estrogen receptor-alpha mRNA with increasing estrogen dose. We conclude that, in this menopausal rat model, local estrogen treatment increased total and cross-linked collagen content and markedly stimulated collagen mRNA expression in an inverse dose-effect relationship. High-dose vaginal estrogen resulted in downregulation of estrogen receptor-alpha and loss of estrogen-induced increases in vaginal collagen. These results may have important clinical implications regarding the use of local vaginal estrogen therapy and its role as an adjunctive treatment in women with loss of vaginal support. PMID:25537371

  16. Chitosan: collagen sponges. In vitro mineralization

    International Nuclear Information System (INIS)

    Martins, Virginia da C.A.; Silva, Gustavo M.; Plepis, Ana Maria G.

    2011-01-01

    The regeneration of bone tissue is a problem that affects many people and scaffolds for bone tissue growth has been widely studied. The aim of this study was the in vitro mineralization of chitosan, chitosan:native collagen and chitosan:anionic collagen sponges. The sponges were obtained by lyophilization and mineralization was made by soaking the sponges in alternating solutions containing Ca 2+ and PO 4 3- . The mineralization was confirmed by infrared spectroscopy, energy dispersive X-ray and X-ray diffraction observing the formation of phosphate salts, possibly a carbonated hydroxyapatite since Ca/P=1.80. The degree of mineralization was obtained by thermogravimetry calculating the amount of residue at 750 deg C. The chitosan:anionic collagen sponge showed the highest degree of mineralization probably due to the fact that anionic collagen provides additional sites for interaction with the inorganic phase. (author)

  17. The minor collagens in articular cartilage

    DEFF Research Database (Denmark)

    Luo, Yunyun; Sinkeviciute, Dovile; He, Yi

    2017-01-01

    Articular cartilage is a connective tissue consisting of a specialized extracellular matrix (ECM) that dominates the bulk of its wet and dry weight. Type II collagen and aggrecan are the main ECM proteins in cartilage. However, little attention has been paid to less abundant molecular components......, especially minor collagens, including type IV, VI, IX, X, XI, XII, XIII, and XIV, etc. Although accounting for only a small fraction of the mature matrix, these minor collagens not only play essential structural roles in the mechanical properties, organization, and shape of articular cartilage, but also...... fulfil specific biological functions. Genetic studies of these minor collagens have revealed that they are associated with multiple connective tissue diseases, especially degenerative joint disease. The progressive destruction of cartilage involves the degradation of matrix constituents including...

  18. Glycine functionalized alumina nanoparticles stabilize collagen in ...

    Indian Academy of Sciences (India)

    Al2O3 nanoparticles thereby suggesting ... 1. Introduction. Collagen is a naturally occurring skin protein in animal tis- ... easily adsorb on the surface of the nanoparticles and amino .... [19,23], agglomeration is prevented by the electrostatic.

  19. Properties of Chitosan-Laminated Collagen Film

    Directory of Open Access Journals (Sweden)

    Vera Lazić

    2012-01-01

    Full Text Available The objective of this study is to determine physical, mechanical and barrier properties of chitosan-laminated collagen film. Commercial collagen film, which is used for making collagen casings for dry fermented sausage production, was laminated with chitosan film layer in order to improve the collagen film barrier properties. Different volumes of oregano essential oil per 100 mL of filmogenic solution were added to chitosan film layer: 0, 0.2, 0.4, 0.6 and 0.8 mL to optimize water vapour barrier properties. Chitosan layer with 0.6 or 0.8 % of oregano essential oil lowered the water vapour transmission rate to (1.85±0.10·10–6 and (1.78±0.03·10–6 g/(m2·s·Pa respectively, compared to collagen film ((2.51±0.05·10–6 g/(m2·s·Pa. However, chitosan-laminated collagen film did not show improved mechanical properties compared to the collagen one. Tensile strength decreased from (54.0±3.8 MPa of the uncoated collagen film to (36.3±4.0 MPa when the film was laminated with 0.8 % oregano essential oil chitosan layer. Elongation at break values of laminated films did not differ from those of collagen film ((18.4±2.7 %. Oxygen barrier properties were considerably improved by lamination. Oxygen permeability of collagen film was (1806.8±628.0·10–14 cm3/(m·s·Pa and values of laminated films were below 35·10–14 cm3/(m·s·Pa. Regarding film appearance and colour, lamination with chitosan reduced lightness (L and yellowness (+b of collagen film, while film redness (+a increased. These changes were not visible to the naked eye.

  20. Collagen Accumulation in Osteosarcoma Cells lacking GLT25D1 Collagen Galactosyltransferase.

    Science.gov (United States)

    Baumann, Stephan; Hennet, Thierry

    2016-08-26

    Collagen is post-translationally modified by prolyl and lysyl hydroxylation and subsequently by glycosylation of hydroxylysine. Despite the widespread occurrence of the glycan structure Glc(α1-2)Gal linked to hydroxylysine in animals, the functional significance of collagen glycosylation remains elusive. To address the role of glycosylation in collagen expression, folding, and secretion, we used the CRISPR/Cas9 system to inactivate the collagen galactosyltransferase GLT25D1 and GLT25D2 genes in osteosarcoma cells. Loss of GLT25D1 led to increased expression and intracellular accumulation of collagen type I, whereas loss of GLT25D2 had no effect on collagen secretion. Inactivation of the GLT25D1 gene resulted in a compensatory induction of GLT25D2 expression. Loss of GLT25D1 decreased collagen glycosylation by up to 60% but did not alter collagen folding and thermal stability. Whereas cells harboring individually inactivated GLT25D1 and GLT25D2 genes could be recovered and maintained in culture, cell clones with simultaneously inactive GLT25D1 and GLT25D2 genes could be not grown and studied, suggesting that a complete loss of collagen glycosylation impairs osteosarcoma cell proliferation and viability. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Collagen XII myopathy with rectus femoris atrophy and collagen XII retention in fibroblasts

    DEFF Research Database (Denmark)

    Witting, Nanna; Krag, Thomas; Werlauff, Ulla

    2018-01-01

    INTRODUCTION: Mutation in the collagen XII gene (COL12A1) was recently reported to induce Bethlem myopathy. We describe a family affected by collagen XII-related myopathy in 3 generations. METHODS: Systematic interview, clinical examination, skin biopsies, and MRI of muscle were used. RESULTS...... affection and abnormal collagen XII retention in fibroblasts. MRI disclosed a selective wasting of the rectus femoris muscle. DISCUSSION: COL12A1 mutations should be considered in patients with a mild Bethlem phenotype who present with selective wasting of the rectus femoris, absence of the outside......-in phenomenon on MRI, and abnormal collagen XII retention in fibroblasts. Muscle Nerve, 2018....

  2. [The effect of calcitonin gene-related peptide on collagen accumulation in pulmonary arteries of rats with hypoxic pulmonary arterial hypertension].

    Science.gov (United States)

    Li, Xian-Wei; Du, Jie; Li, Yuan-Jian

    2013-03-01

    To observe the effect of calcitonin gene-related peptide (CGRP) on pulmonary vascular collagen accumulation in hypoxia rats in order to study the effect of CGRP on hypoxic pulmonary vascular structural remodeling and its possible mechanism. Rats were acclimated for 1 week, and then were randomly divided into three groups: normoxia group, hypoxia group, and hypoxia plus capsaicin group. Pulmonary arterial hypertension was induced by hypoxia in rats. Hypoxia plus capsaicin group, rats were given capsaicin (50 mg/(kg x d), s.c) 4 days before hypoxia to deplete endogenous CGRP. Hypoxia (3% O2) stimulated proliferation of pulmonary arterial smooth muscle cells (PASMCs) and proliferation was measured by BrdU marking. The expression levels of CGRP, phosphorylated ERK1/2 (p-ERK1/ 2), collagen I and collagen III were detected by real-time PCR or Western blot. Right ventricle systolic pressure (RVSP) and mean pulmonary arterial pressure (mPAP) of pulmonary arterial hypertension (PAH) rats induced by hypoxia were higher than those of normoxia rats. By HE and Masson staining, it was demonstrated that hypoxia also significantly induced hypertrophy of pulmonary arteries and increased level of collagen accumulation. Hypoxia dramatically decreased the CGRP level and increased the expression of p-ERK1/2, collagen I, collagen III in pulmonary arteries. All these effects of hypoxia were further aggravated by pre-treatment of rats with capsaicin. CGRP concentration-dependently inhibited hypoxia-induced proliferation of PASMCs, markedly decreased the expression of p-ERK1/2, collagen I and collagen III. All these effects of CGRP were abolished in the presence of CGRP8-37. These results suggest that CGRP might inhibit hypoxia-induced PAH and pulmonary vascular remodeling, through inhibiting phosphorylation of ERK1/2 and alleviating the collagen accumulation of pulmonary arteries.

  3. Imaging Prostate Cancer Microenvironment by Collagen Hybridization

    Science.gov (United States)

    2015-10-01

    diagnosis, staging, and treatment of numerous connective tissue disorders and diseases. Standard antibody staining methods that rely on epitopes of a...CMP can be used to detect mechanical damage to collagen in tendon which could be used for diagnostic and therapeutics of musculoskeletal injury which...13. SUPPLEMENTARY NOTES 14. ABSTRACT The major goal of the proposed work is to develop new PCa imaging methods based on the collagen mimetic peptide

  4. Oriented collagen fibers direct tumor cell intravasation

    KAUST Repository

    Han, Weijing

    2016-09-24

    In this work, we constructed a Collagen I-Matrigel composite extracellular matrix (ECM). The composite ECM was used to determine the influence of the local collagen fiber orientation on the collective intravasation ability of tumor cells. We found that the local fiber alignment enhanced cell-ECM interactions. Specifically, metastatic MDA-MB-231 breast cancer cells followed the local fiber alignment direction during the intravasation into rigid Matrigel (∼10 mg/mL protein concentration).

  5. Collagen Fibrils: Nature's Highly Tunable Nonlinear Springs.

    Science.gov (United States)

    Andriotis, Orestis G; Desissaire, Sylvia; Thurner, Philipp J

    2018-03-21

    Tissue hydration is well known to influence tissue mechanics and can be tuned via osmotic pressure. Collagen fibrils are nature's nanoscale building blocks to achieve biomechanical function in a broad range of biological tissues and across many species. Intrafibrillar covalent cross-links have long been thought to play a pivotal role in collagen fibril elasticity, but predominantly at large, far from physiological, strains. Performing nanotensile experiments of collagen fibrils at varying hydration levels by adjusting osmotic pressure in situ during atomic force microscopy experiments, we show the power the intrafibrillar noncovalent interactions have for defining collagen fibril tensile elasticity at low fibril strains. Nanomechanical tensile tests reveal that osmotic pressure increases collagen fibril stiffness up to 24-fold in transverse (nanoindentation) and up to 6-fold in the longitudinal direction (tension), compared to physiological saline in a reversible fashion. We attribute the stiffening to the density and strength of weak intermolecular forces tuned by hydration and hence collagen packing density. This reversible mechanism may be employed by cells to alter their mechanical microenvironment in a reversible manner. The mechanism could also be translated to tissue engineering approaches for customizing scaffold mechanics in spatially resolved fashion, and it may help explain local mechanical changes during development of diseases and inflammation.

  6. Elevated expression of type VII collagen in the skin of patients with systemic sclerosis. Regulation by transforming growth factor-beta.

    OpenAIRE

    Rudnicka, L; Varga, J; Christiano, A M; Iozzo, R V; Jimenez, S A; Uitto, J

    1994-01-01

    A hallmark of systemic sclerosis (SSc) is the development of tissue fibrosis. Excessive production of several connective tissue components normally present in the dermis, including type I, III, V, and VI collagens as well as fibronectin and proteoglycans, is a consistent finding in the skin of SSc patients. Type VII collagen is a major constituent of anchoring fibrils, present in the skin at the dermal-epidermal basement membrane zone. TGF-beta has been shown to upregulate the expression of t...

  7. Collagen as potential cell scaffolds for tissue engineering.

    Science.gov (United States)

    Annuar, N; Spier, R E

    2004-05-01

    Selections of collagen available commercially were tested for their biocompatibility as scaffold to promote cell growth in vitro via simple collagen fast test and cultivation of mammalian cells on the selected type of collagen. It was found that collagen type C9791 promotes the highest degree of aggregation as well as cells growth. This preliminary study also indicated potential use of collagen as scaffold in engineered tissue.

  8. Evaluation of Anterior Vertebral Interbody Fusion Using Osteogenic Mesenchymal Stem Cells Transplanted in Collagen Sponge.

    Science.gov (United States)

    Yang, Wencheng; Dong, Youhai; Hong, Yang; Guang, Qian; Chen, Xujun

    2016-05-01

    The study used a rabbit model to achieve anterior vertebral interbody fusion using osteogenic mesenchymal stem cells (OMSCs) transplanted in collagen sponge. We investigated the effectiveness of graft material for anterior vertebral interbody fusion using a rabbit model by examining the OMSCs transplanted in collagen sponge. Anterior vertebral interbody fusion is commonly performed. Although autogenous bone graft remains the gold-standard fusion material, it requires a separate surgical procedure and is associated with significant short-term and long-term morbidity. Recently, mesenchymal stem cells from bone marrow have been studied in various fields, including posterolateral spinal fusion. Thus, we hypothesized that cultured OMSCs transplanted in porous collagen sponge could be used successfully even in anterior vertebral interbody fusion. Forty mature male White Zealand rabbits (weight, 3.5-4.5 kg) were randomly allocated to receive one of the following graft materials: porous collagen sponge plus cultured OMSCs (group I); porous collagen sponge alone (group II); autogenous bone graft (group III); and nothing (group IV). All animals underwent anterior vertebral interbody fusion at the L4/L5 level. The lumbar spine was harvested en bloc, and the new bone formation and spinal fusion was evaluated using radiographic analysis, microcomputed tomography, manual palpation test, and histologic examination at 8 and 12 weeks after surgery. New bone formation and bony fusion was evident as early as 8 weeks in groups I and III. And there was no statistically significant difference between 8 and 12 weeks. At both time points, by microcomputed tomography and histologic analysis, new bone formation was observed in both groups I and III, fibrous tissue was observed and there was no new bone in both groups II and IV; by manual palpation test, bony fusion was observed in 40% (4/10) of rabbits in group I, 70% (7/10) of rabbits in group III, and 0% (0/10) of rabbits in both groups

  9. Novel chitosan/collagen scaffold containing transforming growth factor-β1 DNA for periodontal tissue engineering

    International Nuclear Information System (INIS)

    Zhang Yufeng; Cheng Xiangrong; Wang Jiawei; Wang Yining; Shi Bin; Huang Cui; Yang Xuechao; Liu Tongjun

    2006-01-01

    The current rapid progression in tissue engineering and local gene delivery system has enhanced our applications to periodontal tissue engineering. In this study, porous chitosan/collagen scaffolds were prepared through a freeze-drying process, and loaded with plasmid and adenoviral vector encoding human transforming growth factor-β1 (TGF-β1). These scaffolds were evaluated in vitro by analysis of microscopic structure, porosity, and cytocompatibility. Human periodontal ligament cells (HPLCs) were seeded in this scaffold, and gene transfection could be traced by green fluorescent protein (GFP). The expression of type I and type III collagen was detected with RT-PCR, and then these scaffolds were implanted subcutaneously into athymic mice. Results indicated that the pore diameter of the gene-combined scaffolds was lower than that of pure chitosan/collagen scaffold. The scaffold containing Ad-TGF-β1 exhibited the highest proliferation rate, and the expression of type I and type III collagen up-regulated in Ad-TGF-β1 scaffold. After implanted in vivo, EGFP-transfected HPLCs not only proliferated but also recruited surrounding tissue to grow in the scaffold. This study demonstrated the potential of chitosan/collagen scaffold combined Ad-TGF-β1 as a good substrate candidate in periodontal tissue engineering

  10. Collagen-binding peptidoglycans inhibit MMP mediated collagen degradation and reduce dermal scarring.

    Directory of Open Access Journals (Sweden)

    Kate Stuart

    Full Text Available Scarring of the skin is a large unmet clinical problem that is of high patient concern and impact. Wound healing is complex and involves numerous pathways that are highly orchestrated, leaving the skin sealed, but with abnormal organization and composition of tissue components, namely collagen and proteoglycans, that are then remodeled over time. To improve healing and reduce or eliminate scarring, more rapid restoration of healthy tissue composition and organization offers a unique approach for development of new therapeutics. A synthetic collagen-binding peptidoglycan has been developed that inhibits matrix metalloproteinase-1 and 13 (MMP-1 and MMP-13 mediated collagen degradation. We investigated the synthetic peptidoglycan in a rat incisional model in which a single dose was delivered in a hyaluronic acid (HA vehicle at the time of surgery prior to wound closure. The peptidoglycan treatment resulted in a significant reduction in scar tissue at 21 days as measured by histology and visual analysis. Improved collagen architecture of the treated wounds was demonstrated by increased tensile strength and transmission electron microscopy (TEM analysis of collagen fibril diameters compared to untreated and HA controls. The peptidoglycan's mechanism of action includes masking existing collagen and inhibiting MMP-mediated collagen degradation while modulating collagen organization. The peptidoglycan can be synthesized at low cost with unique design control, and together with demonstrated preclinical efficacy in reducing scarring, warrants further investigation for dermal wound healing.

  11. A collagen-binding EGFR antibody fragment targeting tumors with a collagen-rich extracellular matrix.

    Science.gov (United States)

    Liang, Hui; Li, Xiaoran; Wang, Bin; Chen, Bing; Zhao, Yannan; Sun, Jie; Zhuang, Yan; Shi, Jiajia; Shen, He; Zhang, Zhijun; Dai, Jianwu

    2016-02-17

    Many tumors over-express collagen, which constitutes the physical scaffold of tumor microenvironment. Collagen has been considered to be a target for cancer therapy. The collagen-binding domain (CBD) is a short peptide, which could bind to collagen and achieve the sustained release of CBD-fused proteins in collagen scaffold. Here, a collagen-binding EGFR antibody fragment was designed and expressed for targeting the collagen-rich extracellular matrix in tumors. The antibody fragment (Fab) of cetuximab was fused with CBD (CBD-Fab) and expressed in Pichia pastoris. CBD-Fab maintained antigen binding and anti-tumor activity of cetuximab and obtained a collagen-binding ability in vitro. The results also showed CBD-Fab was mainly enriched in tumors and had longer retention time in tumors in A431 s.c. xenografts. Furthermore, CBD-Fab showed a similar therapeutic efficacy as cetuximab in A431 xenografts. Although CBD-Fab hasn't showed better therapeutic effects than cetuximab, its smaller molecular and special target may be applicable as antibody-drug conjugates (ADC) or immunotoxins.

  12. Adherence, proliferation and collagen turnover by human fibroblasts seeded into different types of collagen sponges

    NARCIS (Netherlands)

    Middelkoop, E.; de Vries, H. J.; Ruuls, L.; Everts, V.; Wildevuur, C. H.; Westerhof, W.

    1995-01-01

    We describe an in vitro model that we have used to evaluate dermal substitutes and to obtain data on cell proliferation, the rate of degradation of the dermal equivalent, contractibility and de novo synthesis of collagen. We tested three classes of collagenous materials: (1) reconstituted

  13. Fluorescently labaled collagen binding proteins allow specific visualization of collagen in tissues and live cell culture

    NARCIS (Netherlands)

    Krahn, K.B.N.; Bouten, C.V.C.; Tuijl, van S.; Zandvoort, van M.; Merkx, M.

    2006-01-01

    Visualization of the formation and orientation of collagen fibers in tissue engineering experiments is crucial for understanding the factors that determine the mechanical properties of tissues. In this study, collagen-specific fluorescent probes were developed using a new approach that takes

  14. ADHERENCE, PROLIFERATION AND COLLAGEN TURNOVER BY HUMAN FIBROBLASTS SEEDED INTO DIFFERENT TYPES OF COLLAGEN SPONGES

    NARCIS (Netherlands)

    MIDDELKOOP, E; DEVRIES, HJC; RUULS, L; EVERTS, [No Value; WILDEVUUR, CHR; WESTERHOF, W

    We describe an in vitro model that we have used to evaluate dermal substitutes and to obtain data on cell proliferation, the rate of degradation of the dermal equivalent, contractibility and de novo synthesis of collagen. We tested three classes of collagenous materials: (1) reconstituted

  15.  Mutations of noncollagen genes in osteogenesis imperfecta – implications of the gene products in collagen biosynthesis and pathogenesis of disease

    Directory of Open Access Journals (Sweden)

    Anna Galicka

    2012-06-01

    Full Text Available  Recent investigations revealed that the “brittle bone” phenotype in osteogenesis imperfecta (OI is caused not only by dominant mutations in collagen type I genes, but also by recessively inherited mutations in genes responsible for the post-translational processing of type I procollagen as well as for bone formation. The phenotype of patients with mutations in noncollagen genes overlaps with very severe type III and lethal type II OI caused by mutations in collagen genes. Mutations in genes that encode proteins involved in collagen prolyl 3-hydroxylation (P3H1/CRTAP/CyPB eliminated Pro986 hydroxylation and caused an increase in modification of collagen helix by prolyl 4-hydroxylase and lysyl hydroxylase. However, the importance of these disturbances in the disease pathomechanism is not known. Loss of complex proteins’ function as collagen chaperones may dominate the disease mechanism. The latest findings added to the spectrum of OI-causing and collagen-influencing factors other chaperones (HSP47 and FKBP65 and protein BMP-1, which emphasizes the complexity of collagen folding and secretion as well as their importance in bone formation. Furthermore, mutations in genes encoding transcription factor SP7/Osterix and pigment epithelium-derived factor (PEDF constitute a novel mechanism for OI, which is independent of changes in biosynthesis and processing of collagen.

  16. Detection of COL III in Parchment by Amino Acid Analysis

    DEFF Research Database (Denmark)

    Vestergaard Poulsen Sommer, Dorte; Larsen, René

    2016-01-01

    Cultural heritage parchments made from the reticular dermis of animals have been subject to studies of deterioration and conservation by amino acid analysis. The reticular dermis contains a varying mixture of collagen I and III (COL I and III). When dealing with the results of the amino acid...... analyses, till now the COL III content has not been taken into account. Based on the available amino acid sequences we present a method for determining the amount of COL III in the reticular dermis of new and historical parchments calculated from the ratio of Ile/Val. We find COL III contents between 7...... and 32 % in new parchments and between 0.2 and 40 % in the historical parchments. This is consistent with results in the literature. The varying content of COL III has a significant influence on the uncertainty of the amino acid analysis. Although we have not found a simple correlation between the COL...

  17. Qualitative and quantitative assessment of collagen and elastin in annulus fibrosus of the physiologic and scoliotic intervertebral discs.

    Science.gov (United States)

    Kobielarz, Magdalena; Szotek, Sylwia; Głowacki, Maciej; Dawidowicz, Joanna; Pezowicz, Celina

    2016-09-01

    The biophysical properties of the annulus fibrosus of the intervertebral disc are determined by collagen and elastin fibres. The progression of scoliosis is accompanied by a number of pathological changes concerning these structural proteins. This is a major cause of dysfunction of the intervertebral disc. The object of the study were annulus fibrosus samples excised from intervertebral discs of healthy subjects and patients treated surgically for scoliosis in the thoracolumbar or lumbar spine. The research material was subjected to structural analysis by light microscopy and quantitative analysis of the content of collagen types I, II, III and IV as well as elastin by immunoenzymatic test (ELISA). A statistical analysis was conducted to assess the impact of the sampling site (Mann-Whitney test, α=0.05) and scoliosis (Wilcoxon matched pairs test, α=0.05) on the obtained results. The microscopic studies conducted on scoliotic annulus fibrosus showed a significant architectural distortion of collagen and elastin fibres. Quantitative biochemical assays demonstrated region-dependent distribution of only collagen types I and II in the case of healthy intervertebral discs whereas in the case of scoliotic discs region-dependent distribution concerned all examined proteins of the extracellular matrix. Comparison of scoliotic and healthy annulus fibrosus revealed a significant decrease in the content of collagen type I and elastin as well as a slight increase in the proportion of collagen types III and IV. The content of collagen type II did not differ significantly between both groups. The observed anomalies are a manifestation of degenerative changes affecting annulus fibrosus of the intervertebral disc in patients suffering from scoliosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Role of Myocardial Collagen in Severe Aortic Stenosis With Preserved Ejection Fraction and Symptoms of Heart Failure.

    Science.gov (United States)

    Echegaray, Kattalin; Andreu, Ion; Lazkano, Ane; Villanueva, Iñaki; Sáenz, Alberto; Elizalde, María Reyes; Echeverría, Tomás; López, Begoña; Garro, Asier; González, Arantxa; Zubillaga, Elena; Solla, Itziar; Sanz, Iñaki; González, Jesús; Elósegui-Artola, Alberto; Roca-Cusachs, Pere; Díez, Javier; Ravassa, Susana; Querejeta, Ramón

    2017-10-01

    We investigated the anatomical localization, biomechanical properties, and molecular phenotype of myocardial collagen tissue in 40 patients with severe aortic stenosis with preserved ejection fraction and symptoms of heart failure. Two transmural biopsies were taken from the left ventricular free wall. Mysial and nonmysial regions of the collagen network were analyzed. Myocardial collagen volume fraction (CVF) was measured by picrosirius red staining. Young's elastic modulus (YEM) was measured by atomic force microscopy in decellularized slices to assess stiffness. Collagen types I and III were measured as C I VF and C III VF, respectively, by confocal microscopy in areas with YEM evaluation. Compared with controls, patients exhibited increased mysial and nonmysial CVF and nonmysial:mysial CVF ratio (P < .05). In patients, nonmysial CVF (r = 0.330; P = .046) and the nonmysial:mysial CVF ratio (r = 0.419; P = .012) were directly correlated with the ratio of maximal early transmitral flow velocity in diastole to early mitral annulus velocity in diastole. Both the C I VF:C III VF ratio and YEM were increased (P ≤ .001) in nonmysial regions compared with mysial regions in patients, with a direct correlation (r = 0.895; P < .001) between them. These findings suggest that, in patients with severe aortic stenosis with preserved ejection fraction and symptoms of heart failure, diastolic dysfunction is associated with increased nonmysial deposition of collagen, predominantly type I, resulting in increased extracellular matrix stiffness. Therefore, the characteristics of collagen tissue may contribute to diastolic dysfunction in these patients. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  19. The insulin-like growth factor axis and collagen turnover in asthmatic children treated with inhaled budesonide

    DEFF Research Database (Denmark)

    Wolthers, O D; Juul, A; Hansen, M

    1995-01-01

    Serum concentrations of growth hormone-dependent insulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3), the carboxy terminal propeptide of type I procollagen (PICP), the carboxy terminal pyridinoline cross-linked telopeptide of type I collagen (ICTP) and ...... the calculations (p reduced synthesis of type III collagen. A similar trend was observed in ICTP levels when the 400 micrograms period was excluded from the calculations (p = 0.05; z = -1.9). No other statistically significant variations were seen....

  20. Biophysical behavior of Scomberoides commersonianus skin collagen.

    Science.gov (United States)

    Kolli, Nagamalleswari; Joseph, K Thomas; Ramasami, T

    2002-06-01

    Some biophysical characteristics of the skin collagen from Scomberoides commersonianus were measured and compared to those of rat tail tendon. Stress-strain data indicate that the strain at break as well as the tensile strength of the fish skin without scales increased significantly. The maximum tension in case of rat skin is at least a factor of two higher than that observed in fish skin. The much lower hydrothermal isometric tension measurements observed in fish skin are attributable to a lesser number of heat stable crosslinks. Stress relaxation measurements in the fish skin indicate that more than one relaxation process may be involved in the stabilization of collagenous matrix. The observed differences in the biophysical behavior of fish skin may well arise from combination of changes in extent of hydroxylation of proline in collagen synthesis, hydrogen bond network and fibril orientation as compared to rat tail tendon.

  1. Collagenous gastritis in the pediatric age

    Directory of Open Access Journals (Sweden)

    Antonio Rosell-Camps

    2015-05-01

    Full Text Available Collagenous gastritis (CG is an uncommon condition known in the pediatric age. It is characterized by the presence of subepithelial collagen bands (> 10 μm associated with lymphoplasmacytic infiltration of the stomach's lamina propria. Symptoms manifested by patients with CG may be common with many other disorders. It typically manifests with epigastralgia, vomiting, and iron deficiency during pre-adolescence. This condition's pathophysiology remains unclear. In contrast to adults, where association with collagenous colitis and other autoimmune conditions is more common, pediatric involvement is usually confined to the stomach. Drugs of choice include proton pump inhibitors and corticoids. A case is reported of a 12-year-old girl with abdominal pain and ferritin deficiency who was diagnosed with CG based on gastric biopsy and experienced a favorable outcome.

  2. Tooth agenesis in osteogenesis imperfecta related to mutations in the collagen type I genes.

    Science.gov (United States)

    Malmgren, B; Andersson, K; Lindahl, K; Kindmark, A; Grigelioniene, G; Zachariadis, V; Dahllöf, G; Åström, E

    2017-01-01

    Osteogenesis imperfecta (OI) is a heterogeneous group of disorders of connective tissue, mainly caused by mutations in the collagen type I genes (COL1A1 and COL1A2). Tooth agenesis is a common feature of OI. We investigated the association between tooth agenesis and collagen type I mutations in individuals with OI. In this cohort study, 128 unrelated individuals with OI were included. Panoramic radiographs were analyzed regarding dentinogenesis imperfecta (DGI) and congenitally missing teeth. The collagen I genes were sequenced in all individuals, and in 25, multiplex ligation-dependent probe amplification was performed. Mutations in the COL1A1 and COL1A2 genes were found in 104 of 128 individuals. Tooth agenesis was diagnosed in 17% (hypodontia 11%, oligodontia 6%) and was more frequent in those with DGI (P = 0.016), and in those with OI type III, 47%, compared to those with OI types I, 12% (P = 0.003), and IV, 13% (P = 0.017). Seventy-five percent of the individuals with oligodontia (≥6 missing teeth) had qualitative mutations, but there was no association with OI type, gender, or presence of DGI. The prevalence of tooth agenesis is high (17%) in individuals with OI, and OI caused by a qualitative collagen I mutation is associated with oligodontia. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Distinct characteristics of mandibular bone collagen relative to long bone collagen: relevance to clinical dentistry.

    Science.gov (United States)

    Matsuura, Takashi; Tokutomi, Kentaro; Sasaki, Michiko; Katafuchi, Michitsuna; Mizumachi, Emiri; Sato, Hironobu

    2014-01-01

    Bone undergoes constant remodeling throughout life. The cellular and biochemical mechanisms of bone remodeling vary in a region-specific manner. There are a number of notable differences between the mandible and long bones, including developmental origin, osteogenic potential of mesenchymal stem cells, and the rate of bone turnover. Collagen, the most abundant matrix protein in bone, is responsible for determining the relative strength of particular bones. Posttranslational modifications of collagen, such as intermolecular crosslinking and lysine hydroxylation, are the most essential determinants of bone strength, although the amount of collagen is also important. In comparison to long bones, the mandible has greater collagen content, a lower amount of mature crosslinks, and a lower extent of lysine hydroxylation. The great abundance of immature crosslinks in mandibular collagen suggests that there is a lower rate of cross-link maturation. This means that mandibular collagen is relatively immature and thus more readily undergoes degradation and turnover. The greater rate of remodeling in mandibular collagen likely renders more flexibility to the bone and leaves it more suited to constant exercise. As reviewed here, it is important in clinical dentistry to understand the distinctive features of the bones of the jaw.

  4. Distinct Characteristics of Mandibular Bone Collagen Relative to Long Bone Collagen: Relevance to Clinical Dentistry

    Directory of Open Access Journals (Sweden)

    Takashi Matsuura

    2014-01-01

    Full Text Available Bone undergoes constant remodeling throughout life. The cellular and biochemical mechanisms of bone remodeling vary in a region-specific manner. There are a number of notable differences between the mandible and long bones, including developmental origin, osteogenic potential of mesenchymal stem cells, and the rate of bone turnover. Collagen, the most abundant matrix protein in bone, is responsible for determining the relative strength of particular bones. Posttranslational modifications of collagen, such as intermolecular crosslinking and lysine hydroxylation, are the most essential determinants of bone strength, although the amount of collagen is also important. In comparison to long bones, the mandible has greater collagen content, a lower amount of mature crosslinks, and a lower extent of lysine hydroxylation. The great abundance of immature crosslinks in mandibular collagen suggests that there is a lower rate of cross-link maturation. This means that mandibular collagen is relatively immature and thus more readily undergoes degradation and turnover. The greater rate of remodeling in mandibular collagen likely renders more flexibility to the bone and leaves it more suited to constant exercise. As reviewed here, it is important in clinical dentistry to understand the distinctive features of the bones of the jaw.

  5. Immune responses to implanted human collagen graft in rats

    International Nuclear Information System (INIS)

    Quteish, D.; Dolby, A.E.

    1991-01-01

    Immunity to collagen implants may be mediated by cellular and humoral immune responses. To examine the possibility of such immunological reactivity and crossreactivity to collagen, 39 Sprague-Dawley rats (female, 10 weeks old, approximately 250 g wt) were implanted subcutaneously at thigh sites with crosslinked, freeze-dried human placental type I collagen grafts (4x4x2 mm) which had been irradiated (520 Gray) or left untreated. Blood was obtained by intracardiac sampling prior to implantation or from normal rats, and at various times afterwards when the animals were sacrificed. The sera from these animals were examined for circulating antibodies to human, bovine and rat tail (type I) collagens by enzyme-linked immunosorbent assay (ELISA). Also, the lymphoblastogenic responses of spleen lymphocytes from the irradiated collagen-implanted animals were assessed in culture by measuring thymidine uptake with autologous and normal rat sera in the presence of human bovine type I collagens. Implantation of the irradiated and non-irradiated collagen graft in rats led to a significant increase in the level of circulating antibodies to human collagen. Also antibody to bovine and rat tail collagens was detectable in the animals implanted with irradiated collagen grafts but at a lower level than the human collagen. There was a raised lymphoblastogenic response to both human and bovine collagens. The antibody level and lymphoblastogenesis to the tested collagens gradually decreased towards the end of the post-implantation period. (author)

  6. Types I and III procollagen extension peptides in serum respond to fracture in humans

    DEFF Research Database (Denmark)

    Joerring, S; Jensen, L T; Andersen, G R

    1992-01-01

    Markers of types I and III collagen turnover were measured in serial blood samples in 16 patients with a Colles' fracture. The collagen markers were the carboxy-terminal extension peptide of type I procollagen (PICP) and the amino-terminal extension peptide of type III procollagen (PIIINP......). Significant increases were found of PIIINP within 1 week and of PICP within 2 weeks. This sequential appearance of PIIINP and PICP was found to be in agreement with the appearance of types III and I collagen during early fracture healing as demonstrated in previous animal experimental studies. PICP had...... levelled off after 9 months, whereas PIIINP remained elevated. Osteocalcin, a serum marker of osteoblast activity, increased within 1 week and levelled off after 9 months. Correlations between the change in osteocalcin and those in PICP and PIIINP, respectively, were weak. These new biochemical markers may...

  7. Immunosuppression by fractionated total lymphoid irradiation in collagen arthritis

    International Nuclear Information System (INIS)

    McCune, W.J.; Buckley, J.A.; Belli, J.A.; Trentham, D.E.

    1982-01-01

    Treatments with fractionated total lymphoid irradiation (TLI) and cyclophosphamide were evaluated for rats injected with type II collagen. Preadministration of TLI and repeated injections of cyclophosphamide suppressed the severity of arthritis and lowered antibody titers to collagen significantly. TLI initiated at the onset of collagen arthritis decreased humoral and cellular responses to collagen but did not affect the severity of arthritis. These data demonstrate that both TLi and cyclophosphamide are immunosuppressive in an experimentally inducible autoimmune disease

  8. Measurement of skeletal muscle collagen breakdown by microdialysis

    DEFF Research Database (Denmark)

    Miller, B F; Ellis, D; Robinson, M M

    2011-01-01

    Exercise increases the synthesis of collagen in the extracellular matrix of skeletal muscle. Breakdown of skeletal muscle collagen has not yet been determined because of technical limitations. The purpose of the present study was to use local sampling to determine skeletal muscle collagen breakdown...... collagen breakdown 17–21 h post-exercise, and our measurement of OHP using GC–MS was in agreement with traditional assays....

  9. Collagen gene interactions and endurance running performance

    African Journals Online (AJOL)

    to complete any of the individual components (3.8 km swim, 180 km bike or 42.2 km run) of the 226 km event. The major ... may affect normal collagen fibrillogenesis and alter the mechanical properties of ... using a XP Thermal Cycler (Block model XP-G, BIOER Technology Co.,. Japan). ..... New insights into the function of.

  10. The collagenic architecture of human dura mater.

    Science.gov (United States)

    Protasoni, Marina; Sangiorgi, Simone; Cividini, Andrea; Culuvaris, Gloria Tiffany; Tomei, Giustino; Dell'Orbo, Carlo; Raspanti, Mario; Balbi, Sergio; Reguzzoni, Marcella

    2011-06-01

    Human dura mater is the most external meningeal sheet surrounding the CNS. It provides an efficient protection to intracranial structures and represents the most important site for CSF turnover. Its intrinsic architecture is made up of fibrous tissue including collagenic and elastic fibers that guarantee the maintenance of its biophysical features. The recent technical advances in the repair of dural defects have allowed for the creation of many synthetic and biological grafts. However, no detailed studies on the 3D microscopic disposition of collagenic fibers in dura mater are available. The authors report on the collagenic 3D architecture of normal dura mater highlighting the orientation, disposition in 3 dimensions, and shape of the collagen fibers with respect to the observed layer. Thirty-two dura mater specimens were collected during cranial decompressive surgical procedures, fixed in 2.5% Karnovsky solution, and digested in 1 N NaOH solution. After a routine procedure, the specimens were observed using a scanning electron microscope. The authors distinguished the following 5 layers in the fibrous dura mater of varying thicknesses, orientation, and structures: bone surface, external median, vascular, internal median, and arachnoid layers. The description of the ultrastructural 3D organization of the different layers of dura mater will give us more information for the creation of synthetic grafts that are as similar as possible to normal dura mater. This description will be also related to the study of the neoplastic invasion.

  11. Edaravone suppresses degradation of type II collagen.

    Science.gov (United States)

    Huang, Chen; Liao, Guangjun; Han, Jian; Zhang, Guofeng; Zou, Benguo

    2016-05-13

    Osteoarthritis (OA) is a degenerative joint disease affecting millions of people. The degradation and loss of type II collagen induced by proinflammatory cytokines secreted by chondrocytes, such as factor-α (TNF-α) is an important pathological mechanism to the progression of OA. Edaravone is a potent free radical scavenger, which has been clinically used to treat the neuronal damage following acute ischemic stroke. However, whether Edaravone has a protective effect in articular cartilage hasn't been reported before. In this study, we investigated the chondrocyte protective effects of Edaravone on TNF-α induced degradation of type Ⅱ collagen. And our results indicated that TNF-α treatment resulted in degradation of type Ⅱ collagen, which can be ameliorated by treatment with Edaravone in a dose dependent manner. Notably, it was found that the inhibitory effects of Edaravone on TNF-α-induced reduction of type Ⅱ collagen were mediated by MMP-3 and MMP-13. Mechanistically, we found that Edaravone alleviated TNF-α induced activation of STAT1 and expression of IRF-1. These findings suggest a potential protective effect of Edaravone in OA. Copyright © 2016. Published by Elsevier Inc.

  12. Multiscale structure and mechanics of collagen

    NARCIS (Netherlands)

    Amuasi, H.E.

    2012-01-01

    While we are 70% water, in a very real sense collagen is the stuff we are made of. It is the most abundant protein in multicellular organisms, such as ourselves, making up roughly 25% of our total protein content. If you have ever wondered how the human body holds together all its different parts in

  13. Peroxidase enzymes regulate collagen extracellular matrix biosynthesis.

    Science.gov (United States)

    DeNichilo, Mark O; Panagopoulos, Vasilios; Rayner, Timothy E; Borowicz, Romana A; Greenwood, John E; Evdokiou, Andreas

    2015-05-01

    Myeloperoxidase and eosinophil peroxidase are heme-containing enzymes often physically associated with fibrotic tissue and cancer in various organs, without any direct involvement in promoting fibroblast recruitment and extracellular matrix (ECM) biosynthesis at these sites. We report herein novel findings that show peroxidase enzymes possess a well-conserved profibrogenic capacity to stimulate the migration of fibroblastic cells and promote their ability to secrete collagenous proteins to generate a functional ECM both in vitro and in vivo. Mechanistic studies conducted using cultured fibroblasts show that these cells are capable of rapidly binding and internalizing both myeloperoxidase and eosinophil peroxidase. Peroxidase enzymes stimulate collagen biosynthesis at a post-translational level in a prolyl 4-hydroxylase-dependent manner that does not require ascorbic acid. This response was blocked by the irreversible myeloperoxidase inhibitor 4-amino-benzoic acid hydrazide, indicating peroxidase catalytic activity is essential for collagen biosynthesis. These results suggest that peroxidase enzymes, such as myeloperoxidase and eosinophil peroxidase, may play a fundamental role in regulating the recruitment of fibroblast and the biosynthesis of collagen ECM at sites of normal tissue repair and fibrosis, with enormous implications for many disease states where infiltrating inflammatory cells deposit peroxidases. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  14. Reduced collagen accumulation after major surgery

    DEFF Research Database (Denmark)

    Jorgensen, L N; Kallehave, F; Karlsmark, T

    1996-01-01

    .01)). This decline was significantly higher in the six patients who had a postoperative infection (median 3.02 (range -0.06 to 6.14) versus 0.36 (range -1.56 to 12.60) micrograms/cm, P = 0.02). This study shows that major surgery is associated with impairment of subcutaneous collagen accumulation in a test wound...

  15. Immunoadsorption for collagen and rheumatic diseases.

    Science.gov (United States)

    Yamaji, Ken

    2017-10-01

    The field of therapeutics has seen remarkable progress in the recent years, which has made mainstream drug treatment possible for collagen and rheumatic diseases. However, treatment of intractable cases where drug effectiveness is poor is a challenge. Furthermore, organ damage, concurrent illnesses or allergic reactions make adequate drug therapy impossible. For such cases, therapeutic apheresis is very significant, and it is important how this should be valued related to drug therapies. Therapeutic apheresis for collagen and rheumatic diseases involves the removal of factors that cause and exacerbate the disease; the aim of immunoadsorption, in particular, is to improve the clinical condition of patients with autoimmune disease by selectively removing pathogenic immune complexes and autoantibodies from their plasma. Immunoadsorption, in particular, unlike plasma exchange and DFPP, utilizes a high-affinity column that selectively removes autoantibodies and immune complexes, leaving other plasma components intact. There is no need to replenish fresh frozen plasma or blood products such as albumin and gamma globulin preparations. Immunoadsorption is thus superior in terms of safety, as the risk of infection or allergic reaction relating to these preparations can be avoided. We anticipate future investigations of application of synchronized therapy using drugs and therapeutic apheresis, most notably immunoadsorption, in combination to treat intractable clinical conditions such as collagen and rheumatic diseases. In this paper, our discussion includes the indications for immunoadsorption such as collagen and rheumatic diseases, the relevant conditions and types, as well as the latest understanding related to methods and clinical efficacy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Controlled self assembly of collagen nanoparticle

    Science.gov (United States)

    Papi, Massimiliano; Palmieri, Valentina; Maulucci, Giuseppe; Arcovito, Giuseppe; Greco, Emanuela; Quintiliani, Gianluca; Fraziano, Maurizio; De Spirito, Marco

    2011-11-01

    In recent years carrier-mediated drug delivery has emerged as a powerful methodology for the treatment of various pathologies. The therapeutic index of traditional and novel drugs is enhanced via the increase of specificity due to targeting of drugs to a particular tissue, cell or intracellular compartment, the control over release kinetics, the protection of the active agent, or a combination of the above. Collagen is an important biomaterial in medical applications and ideal as protein-based drug delivery platform due to its special characteristics, such as biocompatibility, low toxicity, biodegradability, and weak antigenicity. While some many attempts have been made, further work is needed to produce fully biocompatible collagen hydrogels of desired size and able to release drugs on a specific target. In this article we propose a novel method to obtain spherical particles made of polymerized collagen surrounded by DMPC liposomes. The liposomes allow to control both the particles dimension and the gelling environment during the collagen polymerization. Furthermore, an optical based method to visualize and quantify each step of the proposed protocol is detailed and discussed.

  17. Collagen-induced arthritis in mice

    NARCIS (Netherlands)

    Bevaart, Lisette; Vervoordeldonk, Margriet J.; Tak, Paul P.

    2010-01-01

    Collagen-induced arthritis (CIA) in mice is an animal model for rheumatoid arthritis (RA) and can be induced in DBA/1 and C57BL/6 mice using different protocols. The CIA model can be used to unravel mechanisms involved in the development of arthritis and is frequently used to study the effect of new

  18. The degree of collagen crosslinks in medical collagen membranes determined by water absorption

    International Nuclear Information System (INIS)

    Braczko, M.; Tederko, A.; Grzybowski, J.

    1994-01-01

    Collagen membranes were crosslinked by using three agents: glutaraldehyde, hexametylenediisocyanate, and UV irradiation. The increasing concentrations of above chemical agents or longer time of UV exposition resulted in the higher cross-links degree and in the decrease of collagen membranes swelling (measured as water absorption), their elasticity and mechanical resistance. According to American standards, the degree of collagen biomaterial cross-links is determined by measuring of the digestion time by pepsin. However, that method is very time-consuming. In our study, we have that a simple, linear regression between logarithm of digestion time by pepsin exists and it was identical for all three cross-linking agents used. We have concluded that determination of water absorption can be an alternative, simple and fast method for examination of collagen membrane cross-links degree. (author). 16 refs, 7 figs, 1 tab

  19. Corneal collagen crosslinking for keratoconus. A review

    Directory of Open Access Journals (Sweden)

    M. M. Bikbov

    2014-10-01

    Full Text Available Photochemical crosslinking is widely applied in ophthalmology. Its biochemical effect is due to the release of singlet oxygen that promotes anaerobic photochemical reaction. Keratoconus is one of the most common corneal ectasia affecting 1 in 250 to 250 000 persons. Currently, the rate of iatrogenic ectasia following eximer laser refractive surgery increases due to biomechanical weakening of the cornea. Morphologically and biochemically, ectasia is characterized by corneal layers thinning, contact between the stroma and epithelium resulting from Bowman’s membrane rupture, chromatin fragmentation in keratocyte nuclei, phagocytosis, abnormal staining and arrangement of collagen fibers, enzyme system disorders, and keratocyte apoptosis. In corneal ectasia, altered enzymatic processes result in the synthesis of abnormal collagen. Collagen packing is determined by the activity of various extracellular matrix enzymes which bind amines and aldehydes of collagen fiber amino acids. In the late stage, morphological changes of Descemet’s membrane (i.e., rupture and detachment develop. Abnormal hexagonal-shaped keratocytes and their apoptosis are the signs of endothelial dystrophy. The lack of analogs in domestic ophthalmology encouraged the scientists of Ufa Eye Research Institute to develop a device for corneal collagen crosslinking. The parameters of ultraviolet (i.e., wavelength, exposure time, power to achieve the desired effect were identified. The specifics of some photosensitizers in the course of the procedure were studied. UFalink, a device for UV irradiation of cornea, and photosensitizer Dextralink were developed and adopted. Due to the high risk of endothelial damage, this treatment is contraindicated in severe keratoconus (CCT less than 400 microns. Major effects of corneal collagen crosslinking are the following: Young’s modulus (modulus of elasticity increase by 328.9 % (on average, temperature tolerance increase by 5

  20. Collagen VII deficient mice show morphologic and histologic corneal changes that phenotypically mimic human dystrophic epidermolysis bullosa of the eye.

    Science.gov (United States)

    Chen, Vicki M; Shelke, Rajani; Nyström, Alexander; Laver, Nora; Sampson, James F; Zhiyi, Cao; Bhat, Najma; Panjwani, Noorjahan

    2018-06-16

    Absence of collagen VII causes blistering of the skin, eyes and many other tissues. This disease is termed dystrophic epidermolysis bullosa (DEB). Corneal fibrosis occurs in up to 41% and vision loss in up to 64% of patients. Standard treatments are supportive and there is no cure. The immune-histologic and morphologic changes in the corneas of the mouse model for this disease have not been described in the literature. Our purpose is to characterize the eyes of these mice to determine if this is an appropriate model for study of human therapeutics. Western blot analysis (WB) and immunohistochemistry (IHC) were performed to assess the relative collagen VII protein levels and its location within the cornea. Additional IHC for inflammatory and fibrotic biomarkers alpha-smooth muscle actin (α-SMA), transforming growth factor-beta (TGF-β), connective tissue growth factor (CTGF), proteinase 3, tenascin C and collagen III were performed. Clinical photographs documenting opacification of the corneas of animals of differing ages were assessed and scored independently by 2 examiners. Histology was then used to investigate morphologic changes. IHC and WB confirmed that these mice are deficient in collagen VII production at the level of the basement membrane when compared with wild-types. IHC showed anomalous deposition of collagen III throughout the stroma. Of the 5 biomarkers tested, TGF-β showed the strongest and most consistently staining. Photographs documented corneal opacities only in mice older than 10 weeks, opacities were not seen in younger animals. Histology showed multiple abnormalities, including epithelial hyperplasia, ulceration, fibrosis, edema, dysplasia, neovascularization and bullae formation. The collagen VII hypomorphic mouse shows reduced collagen VII production at the level of the corneal basement membrane. Corneal changes are similar to pathology seen in humans with this disease. The presence of anomalous stromal collagen III and TGF-β appear to be

  1. Collagen targeting using multivalent protein-functionalized dendrimers

    NARCIS (Netherlands)

    Breurken, M.; Lempens, E.H.M.; Temming, R.P.; Helms, B.A.; Meijer, E.W.; Merkx, M.

    2011-01-01

    Collagen is an attractive marker for tissue remodeling in a variety of common disease processes. Here we report the preparation of protein dendrimers as multivalent collagen targeting ligands by native chemical ligation of the collagen binding protein CNA35 to cysteine-functionalized dendritic

  2. Molecular crowding of collagen: a pathway to produce highly-organized collagenous structures.

    Science.gov (United States)

    Saeidi, Nima; Karmelek, Kathryn P; Paten, Jeffrey A; Zareian, Ramin; DiMasi, Elaine; Ruberti, Jeffrey W

    2012-10-01

    Collagen in vertebrate animals is often arranged in alternating lamellae or in bundles of aligned fibrils which are designed to withstand in vivo mechanical loads. The formation of these organized structures is thought to result from a complex, large-area integration of individual cell motion and locally-controlled synthesis of fibrillar arrays via cell-surface fibripositors (direct matrix printing). The difficulty of reproducing such a process in vitro has prevented tissue engineers from constructing clinically useful load-bearing connective tissue directly from collagen. However, we and others have taken the view that long-range organizational information is potentially encoded into the structure of the collagen molecule itself, allowing the control of fibril organization to extend far from cell (or bounding) surfaces. We here demonstrate a simple, fast, cell-free method capable of producing highly-organized, anistropic collagen fibrillar lamellae de novo which persist over relatively long-distances (tens to hundreds of microns). Our approach to nanoscale organizational control takes advantage of the intrinsic physiochemical properties of collagen molecules by inducing collagen association through molecular crowding and geometric confinement. To mimic biological tissues which comprise planar, aligned collagen lamellae (e.g. cornea, lamellar bone or annulus fibrosus), type I collagen was confined to a thin, planar geometry, concentrated through molecular crowding and polymerized. The resulting fibrillar lamellae show a striking resemblance to native load-bearing lamellae in that the fibrils are small, generally aligned in the plane of the confining space and change direction en masse throughout the thickness of the construct. The process of organizational control is consistent with embryonic development where the bounded planar cell sheets produced by fibroblasts suggest a similar confinement/concentration strategy. Such a simple approach to nanoscale

  3. uPARAP/Endo180 is essential for cellular uptake of collagen and promotes fibroblast collagen adhesion

    DEFF Research Database (Denmark)

    Engelholm, Lars H; List, Karin; Netzel-Arnett, Sarah

    2003-01-01

    The uptake and lysosomal degradation of collagen by fibroblasts constitute a major pathway in the turnover of connective tissue. However, the molecular mechanisms governing this pathway are poorly understood. Here, we show that the urokinase plasminogen activator receptor-associated protein (u......, these cells had diminished initial adhesion to a range of different collagens, as well as impaired migration on fibrillar collagen. These studies identify a central function of uPARAP/Endo180 in cellular collagen interactions....

  4. Comparative Effects of Biodynes, Tocotrienol-Rich Fraction, and Tocopherol in Enhancing Collagen Synthesis and Inhibiting Collagen Degradation in Stress-Induced Premature Senescence Model of Human Diploid Fibroblasts

    Science.gov (United States)

    Jam, Faidruz Azura; Ismail, Zahariah; Wan Ngah, Wan Zurinah

    2013-01-01

    Biodynes, tocotrienol-rich fraction (TRF), and tocopherol have shown antiaging properties. However, the combined effects of these compounds on skin aging are yet to be investigated. This study aimed to elucidate the skin aging effects of biodynes, TRF, and tocopherol on stress-induced premature senescence (SIPS) model of human diploid fibroblasts (HDFs) by determining the expression of collagen and MMPs at gene and protein levels. Primary HDFs were treated with biodynes, TRF, and tocopherol prior to hydrogen peroxide (H2O2) exposure. The expression of COL1A1, COL3A1, MMP1, MMP2, MMP3, and MMP9 genes was determined by qRT-PCR. Type I and type III procollagen proteins were measured by Western blotting while the activities of MMPs were quantified by fluorometric Sensolyte MMP Kit. Our results showed that biodynes, TRF, and tocopherol upregulated collagen genes and downregulated MMP genes (P < 0.05). Type I procollagen and type III procollagen protein levels were significantly increased in response to biodynes, TRF, and tocopherol treatment (P < 0.05) with reduction in MMP-1, MMP-2, MMP-3, and MMP-9 activities (P < 0.05). These findings indicated that biodynes, TRF, and tocopherol effectively enhanced collagen synthesis and inhibited collagen degradation and therefore may protect the skin from aging. PMID:24396567

  5. Comparative Effects of Biodynes, Tocotrienol-Rich Fraction, and Tocopherol in Enhancing Collagen Synthesis and Inhibiting Collagen Degradation in Stress-Induced Premature Senescence Model of Human Diploid Fibroblasts

    Directory of Open Access Journals (Sweden)

    Suzana Makpol

    2013-01-01

    Full Text Available Biodynes, tocotrienol-rich fraction (TRF, and tocopherol have shown antiaging properties. However, the combined effects of these compounds on skin aging are yet to be investigated. This study aimed to elucidate the skin aging effects of biodynes, TRF, and tocopherol on stress-induced premature senescence (SIPS model of human diploid fibroblasts (HDFs by determining the expression of collagen and MMPs at gene and protein levels. Primary HDFs were treated with biodynes, TRF, and tocopherol prior to hydrogen peroxide (H2O2 exposure. The expression of COL1A1, COL3A1, MMP1, MMP2, MMP3, and MMP9 genes was determined by qRT-PCR. Type I and type III procollagen proteins were measured by Western blotting while the activities of MMPs were quantified by fluorometric Sensolyte MMP Kit. Our results showed that biodynes, TRF, and tocopherol upregulated collagen genes and downregulated MMP genes (P<0.05. Type I procollagen and type III procollagen protein levels were significantly increased in response to biodynes, TRF, and tocopherol treatment (P<0.05 with reduction in MMP-1, MMP-2, MMP-3, and MMP-9 activities (P<0.05. These findings indicated that biodynes, TRF, and tocopherol effectively enhanced collagen synthesis and inhibited collagen degradation and therefore may protect the skin from aging.

  6. Use of cis-[18F] fluoro-proline for assessment of exercise-related collagen synthesis in musculoskeletal connective tissue

    DEFF Research Database (Denmark)

    Skovgaard, Dorthe; Kjaer, Andreas; Heinemeier, Katja Maria

    2011-01-01

    Protein turnover in collagen rich tissue is influenced by exercise, but can only with difficulty be studied in vivo due to use of invasive procedure. The present study was done to investigate the possibility of applying the PET-tracer, cis-[(18)F]fluoro-proline (cis-Fpro), for non-invasive assess......Protein turnover in collagen rich tissue is influenced by exercise, but can only with difficulty be studied in vivo due to use of invasive procedure. The present study was done to investigate the possibility of applying the PET-tracer, cis-[(18)F]fluoro-proline (cis-Fpro), for non......-invasive assessment of collagen synthesis in rat musculoskeletal tissues at rest and following short-term (3 days) treadmill running. Musculoskeletal collagen synthesis was studied in rats at rest and 24 h post-exercise. At each session, rats were PET scanned at two time points following injection of cis-FPro: (60...... and 240 min p.i). SUV were calculated for Achilles tendon, calf muscle and tibial bone. The PET-derived results were compared to mRNA expression of collagen type I and III. Tibial bone had the highest SUV that increased significantly (p...

  7. On the role of type IX collagen in the extracellular matrix of cartilage: type IX collagen is localized to intersections of collagen fibrils

    OpenAIRE

    1986-01-01

    The tissue distribution of type II and type IX collagen in 17-d-old chicken embryo was studied by immunofluorescence using polyclonal antibodies against type II collagen and a peptic fragment of type IX collagen (HMW), respectively. Both proteins were found only in cartilage where they were co-distributed. They occurred uniformly throughout the extracellular matrix, i.e., without distinction between pericellular, territorial, and interterritorial matrices. Tissues that undergo endochondral bo...

  8. Type V Collagen is Persistently Altered after Inguinal Hernia Repair

    DEFF Research Database (Denmark)

    Lorentzen, L; Henriksen, N A; Juhl, P

    2018-01-01

    BACKGROUND AND AIMS: Hernia formation is associated with alterations of collagen metabolism. Collagen synthesis and degradation cause a systemic release of products, which are measurable in serum. Recently, we reported changes in type V and IV collagen metabolisms in patients with inguinal...... elective cholecystectomy served as controls (n = 10). Whole venous blood was collected 35-55 months after operation. Biomarkers for type V collagen synthesis (Pro-C5) and degradation (C5M) and those for type IV collagen synthesis (P4NP) and degradation (C4M2) were measured by a solid-phase competitive...... assay. RESULTS: The turnover of type V collagen (Pro-C5/C5M) was slightly higher postoperatively when compared to preoperatively in the inguinal hernia group (P = 0.034). In addition, the results revealed a postoperatively lower type V collagen turnover level in the inguinal hernia group compared...

  9. Demineralized dentin matrix composite collagen material for bone tissue regeneration.

    Science.gov (United States)

    Li, Jianan; Yang, Juan; Zhong, Xiaozhong; He, Fengrong; Wu, Xiongwen; Shen, Guanxin

    2013-01-01

    Demineralized dentin matrix (DDM) had been successfully used in clinics as bone repair biomaterial for many years. However, particle morphology of DDM limited it further applications. In this study, DDM and collagen were prepared to DDM composite collagen material. The surface morphology of the material was studied by scanning electron microscope (SEM). MC3T3-E1 cells responses in vitro and tissue responses in vivo by implantation of DDM composite collagen material in bone defect of rabbits were also investigated. SEM analysis showed that DDM composite collagen material evenly distributed and formed a porous scaffold. Cell culture and animal models results indicated that DDM composite collagen material was biocompatible and could support cell proliferation and differentiation. Histological evaluation showed that DDM composite collagen material exhibited good biocompatibility, biodegradability and osteoconductivity with host bone in vivo. The results suggested that DDM composite collagen material might have a significant clinical advantage and potential to be applied in bone and orthopedic surgery.

  10. Imaging collagen type I fibrillogenesis with high spatiotemporal resolution

    International Nuclear Information System (INIS)

    Stamov, Dimitar R; Stock, Erik; Franz, Clemens M; Jähnke, Torsten; Haschke, Heiko

    2015-01-01

    Fibrillar collagens, such as collagen type I, belong to the most abundant extracellular matrix proteins and they have received much attention over the last five decades due to their large interactome, complex hierarchical structure and high mechanical stability. Nevertheless, the collagen self-assembly process is still incompletely understood. Determining the real-time kinetics of collagen type I formation is therefore pivotal for better understanding of collagen type I structure and function, but visualising the dynamic self-assembly process of collagen I on the molecular scale requires imaging techniques offering high spatiotemporal resolution. Fast and high-speed scanning atomic force microscopes (AFM) provide the means to study such processes on the timescale of seconds under near-physiological conditions. In this study we have applied fast AFM tip scanning to study the assembly kinetics of fibrillar collagen type I nanomatrices with a temporal resolution reaching eight seconds for a frame size of 500 nm. By modifying the buffer composition and pH value, the kinetics of collagen fibrillogenesis can be adjusted for optimal analysis by fast AFM scanning. We furthermore show that amplitude-modulation imaging can be successfully applied to extract additional structural information from collagen samples even at high scan rates. Fast AFM scanning with controlled amplitude modulation therefore provides a versatile platform for studying dynamic collagen self-assembly processes at high resolution. - Highlights: • Continuous non-invasive time-lapse investigation of collagen I fibrillogenesis in situ. • Imaging of collagen I self-assembly with high spatiotemporal resolution. • Application of setpoint modulation to study the hierarchical structure of collagen I. • Observing real-time formation of the D-banding pattern in collagen I

  11. Imaging collagen type I fibrillogenesis with high spatiotemporal resolution

    Energy Technology Data Exchange (ETDEWEB)

    Stamov, Dimitar R, E-mail: stamov@jpk.com [JPK Instruments AG, Bouchéstrasse 12, 12435 Berlin (Germany); Stock, Erik [JPK Instruments AG, Bouchéstrasse 12, 12435 Berlin (Germany); Franz, Clemens M [DFG-Center for Functional Nanostructures (CFN), Karlsruhe Institute of Technology (KIT), Wolfgang-Gaede-Strasse 1a, 76131 Karlsruhe (Germany); Jähnke, Torsten; Haschke, Heiko [JPK Instruments AG, Bouchéstrasse 12, 12435 Berlin (Germany)

    2015-02-15

    Fibrillar collagens, such as collagen type I, belong to the most abundant extracellular matrix proteins and they have received much attention over the last five decades due to their large interactome, complex hierarchical structure and high mechanical stability. Nevertheless, the collagen self-assembly process is still incompletely understood. Determining the real-time kinetics of collagen type I formation is therefore pivotal for better understanding of collagen type I structure and function, but visualising the dynamic self-assembly process of collagen I on the molecular scale requires imaging techniques offering high spatiotemporal resolution. Fast and high-speed scanning atomic force microscopes (AFM) provide the means to study such processes on the timescale of seconds under near-physiological conditions. In this study we have applied fast AFM tip scanning to study the assembly kinetics of fibrillar collagen type I nanomatrices with a temporal resolution reaching eight seconds for a frame size of 500 nm. By modifying the buffer composition and pH value, the kinetics of collagen fibrillogenesis can be adjusted for optimal analysis by fast AFM scanning. We furthermore show that amplitude-modulation imaging can be successfully applied to extract additional structural information from collagen samples even at high scan rates. Fast AFM scanning with controlled amplitude modulation therefore provides a versatile platform for studying dynamic collagen self-assembly processes at high resolution. - Highlights: • Continuous non-invasive time-lapse investigation of collagen I fibrillogenesis in situ. • Imaging of collagen I self-assembly with high spatiotemporal resolution. • Application of setpoint modulation to study the hierarchical structure of collagen I. • Observing real-time formation of the D-banding pattern in collagen I.

  12. Imaging Prostate Cancer Microenvironment by Collagen Hybridization

    Science.gov (United States)

    2016-12-01

    of collagen II remodeling in Rheumatoid arthritis and other cartilage-related diseases or wound repair. We did observe trends in the CMP...proteins in vitro and in vivo has been prepared and submitted to Molecular Pharmaceutics . What do you plan to do during the next reporting period to...or care of human subjects, vertebrate animals, biohazards, and/or select agents Nothing to report. PRODUCTS Journal publications: Lucas L

  13. Collagen Fiber Orientation in Primate Long Bones.

    Science.gov (United States)

    Warshaw, Johanna; Bromage, Timothy G; Terranova, Carl J; Enlow, Donald H

    2017-07-01

    Studies of variation in orientation of collagen fibers within bone have lead to the proposition that these are preferentially aligned to accommodate different kinds of load, with tension best resisted by fibers aligned longitudinally relative to the load, and compression best resisted by transversely aligned fibers. However, previous studies have often neglected to consider the effect of developmental processes, including constraints on collagen fiber orientation (CFO), particularly in primary bone. Here we use circularly polarized light microscopy to examine patterns of CFO in cross-sections from the midshaft femur, humerus, tibia, radius, and ulna in a range of living primate taxa with varied body sizes, phylogenetic relationships and positional behaviors. We find that a preponderance of longitudinally oriented collagen is characteristic of both periosteal primary and intracortically remodeled bone. Where variation does occur among groups, it is not simply understood via interpretations of mechanical loads, although prioritized adaptations to tension and/or shear are considered. While there is some suggestion that CFO may correlate with body size, this relationship is neither consistent nor easily explicable through consideration of size-related changes in mechanical adaptation. The results of our study indicate that there is no clear relationship between CFO and phylogenetic status. One of the principle factors accounting for the range of variation that does exist is primary tissue type, where slower depositing bone is more likely to comprise a larger proportion of oblique to transverse collagen fibers. Anat Rec, 300:1189-1207, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  14. Calcaneal Tendon Collagen Fiber Morphometry and Aging

    Czech Academy of Sciences Publication Activity Database

    Hadraba, Daniel; Janáček, Jiří; Filová, Eva; Lopot, F.; Paesen, R.; Fanta, O.; Jarman, A.; Nečas, A.; Ameloot, M.; Jelen, K.

    2017-01-01

    Roč. 23, č. 5 (2017), s. 1040-1047 ISSN 1431-9276 R&D Projects: GA ČR(CZ) GA16-14758S; GA MŠk(CZ) LO1309; GA MŠk(CZ) LM2015062 Institutional support: RVO:67985823 ; RVO:68378041 Keywords : collagen * aging * crimp * fiber orientation * tendon Subject RIV: EB - Genetics ; Molecular Biology; BO - Biophysics (UEM-P) OBOR OECD: Developmental biology; Biophysics (UEM-P) Impact factor: 1.891, year: 2016

  15. Chemical Stabilisation of Collagen as a Biomimetic

    Directory of Open Access Journals (Sweden)

    R. Gordon Paul

    2003-01-01

    Full Text Available Collagen is the most abundant protein in animals and because of its high mechanical strength and good resistance to degradation has been utilized in a wide range of products in industry whilst its low antigenicity has resulted in its widespread use in medicine. Collagen products can be purified from fibres, molecules reconstituted as fibres or from specific recombinant polypeptides with preferred properties. A common feature of all these biomaterials is the need for stable chemical cross-linking to control the mechanical properties and the residence time in the body, and to some extent the immunogenicity of the device. This can be achieved by a number of different cross-linking agents that react with specific amino acid residues on the collagen molecule imparting individual biochemical, thermal and mechanical characteristics to the biomaterial. In this review we have summarised the major techniques for testing these characteristics and the mechanisms involved in the variety of cross-linking reactions to achieve particular properties..

  16. In vivo determination of arterial collagen synthesis in atherosclerotic rabbits

    International Nuclear Information System (INIS)

    Opsahl, W.P.; DeLuca, D.J.; Ehrhart, L.A.

    1986-01-01

    Collagen and non-collagen protein synthesis rates were determined in vivo in tissues from rabbits fed a control or atherogenic diet supplemented with 2% peanut oil and 0.25% cholesterol for 4 months. Rabbits received a bolus intravenous injection of L-[ 3 H]-proline (1.0 mCi/kg) and unlabeled L-proline (7 mmoles/kg) in 0.9% NaCl. Plasma proline specific activity decreased only 20% over 5 hr and was similar to the specific activity of free proline in tissues. Thoracic aortas from atherosclerotic rabbits exhibited raised plaques covering at least 75% of the surface. Thoracic intima plus a portion of the media (TIM) was separated from the remaining media plus adventitia (TMA). Dry delipidated weight, total collagen content, and collagen as a percent of dry weight were increased significantly in the TIM of atherosclerotic rabbits. Collagen synthesis rates and collagen synthesis as a percent of total protein synthesis were likewise increased both in the TIM and in the abdominal aortas. No differences from controls either in collagen content or collagen synthesis rates were observed in the TMA, lung or skin. These results demonstrate for the first time in vivo that formation of atherosclerotic plaques is associated with increased rates of collagen synthesis. Furthermore, as previously observed with incubations in vitro, collagen synthesis was elevated to a greater extent than noncollagen protein synthesis in atherosclerotic aortas from rabbits fed cholesterol plus peanut oil

  17. Hyaluronan in aged collagen matrix increases prostate epithelial cell proliferation

    Science.gov (United States)

    Damodarasamy, Mamatha; Vernon, Robert B.; Chan, Christina K.; Plymate, Stephen R.; Wight, Thomas N.

    2015-01-01

    The extracellular matrix (ECM) of the prostate, which is comprised primarily of collagen, becomes increasingly disorganized with age, a property that may influence the development of hyperplasia and cancer. Collageous ECM extracted from the tails of aged mice exhibits many characteristics of collagen in aged tissues, including the prostate. When polymerized into a 3-dimensional (3D) gel, these collagen extracts can serve as models for the study of specific cell-ECM interactions. In the present study, we examined the behaviors of human prostatic epithelial cell lines representing normal prostate epithelial cells (PEC), benign prostatic hyperplasia (BPH-1), and adenocarcinoma (LNCaP) cultured in contact with 3D gels made from collagen extracts of young and aged mice. We found that proliferation of PEC, BPH-1, and LNCaP cells were all increased by culture on aged collagen gels relative to young collagen gels. In examining age-associated differences in the composition of the collagen extracts, we found that aged and young collagen had a similar amount of several collagen-associated ECM components, but aged collagen had a much greater content of the glycosaminoglycan hyaluronan (HA) than young collagen. The addition of HA (of similar size and concentration to that found in aged collagen extracts) to cells placed in young collagen elicited significantly increased proliferation in BPH-1 cells, but not in PEC or LNCaP cells, relative to controls not exposed to HA. Of note, histochemical analyses of human prostatic tissues showed significantly higher expression of HA in BPH and prostate cancer stroma relative to stroma of normal prostate. Collectively, these results suggest that changes in ECM involving increased levels of HA contribute to the growth of prostatic epithelium with aging. PMID:25124870

  18. Collagen Structural Hierarchy and Susceptibility to Degradation by Ultraviolet Radiation.

    Science.gov (United States)

    Rabotyagova, Olena S; Cebe, Peggy; Kaplan, David L

    2008-12-01

    Collagen type I is the most abundant extracellular matrix protein in the human body, providing the basis for tissue structure and directing cellular functions. Collagen has complex structural hierarchy, organized at different length scales, including the characteristic triple helical feature. In the present study, the relationship between collagen structure (native vs. denatured) and sensitivity to UV radiation was assessed, with a focus on changes in primary structure, changes in conformation, microstructure and material properties. A brief review of free radical reactions involved in collagen degradation is also provided as a mechanistic basis for the changes observed in the study. Structural and functional changes in the collagens were related to the initial conformation (native vs. denatured) and the energy of irradiation. These changes were tracked using SDS-PAGE to assess molecular weight, Fourier transform infrared (FTIR) spectroscopy to study changes in the secondary structure, and atomic force microscopy (AFM) to characterize changes in mechanical properties. The results correlate differences in sensitivity to irradiation with initial collagen structural state: collagen in native conformation vs. heat-treated (denatured) collagen. Changes in collagen were found at all levels of the hierarchical structural organization. In general, the native collagen triple helix is most sensitive to UV-254nm radiation. The triple helix delays single chain degradation. The loss of the triple helix in collagen is accompanied by hydrogen abstraction through free radical mechanisms. The results received suggest that the effects of electromagnetic radiation on biologically relevant extracellular matrices (collagen in the present study) are important to assess in the context of the state of collagen structure. The results have implications in tissue remodeling, wound repair and disease progression.

  19. Binding of collagens to an enterotoxigenic strain of Escherichia coli

    International Nuclear Information System (INIS)

    Visai, L.; Speziale, P.; Bozzini, S.

    1990-01-01

    An enterotoxigenic strain of Escherichia coli, B34289c, has been shown to bind the N-terminal region of fibronectin with high affinity. We now report that this strain also binds collagen. The binding of 125I-labeled type II collagen to bacteria was time dependent and reversible. Bacteria expressed a limited number of collagen receptors (2.2 x 10(4) per cell) and bound collagen with a Kd of 20 nM. All collagen types tested (I to V) as well as all tested cyanogen bromide-generated peptides [alpha 1(I)CB2, alpha 1(I)CB3, alpha 1(I)CB7, alpha 1(I)CB8, and alpha 2(I)CB4] were recognized by bacterial receptors, as demonstrated by the ability of these proteins to inhibit the binding of 125I-labeled collagen to bacteria. Of several unlabeled proteins tested in competition experiments, fibronectin and its N-terminal region strongly inhibited binding of the radiolabeled collagen to E. coli cells. Conversely, collagen competed with an 125I-labeled 28-kilodalton fibronectin fragment for bacterial binding. Collagen bound to bacteria could be displaced by excess amounts of either unlabeled fibronectin or its N-terminal fragment. Similarly, collagen could displace 125I-labeled N-terminal peptide of fibronectin bound to the bacterial cell surface. Bacteria grown at 41 degrees C or in the presence of glucose did not express collagen or fibronectin receptors. These results indicate the presence of specific binding sites for collagen on the surface of E. coli cells and furthermore that the collagen and fibronectin binding sites are located in close proximity, possibly on the same structure

  20. Collagenous colitis: histopathology and clinical course.

    Science.gov (United States)

    Goff, J S; Barnett, J L; Pelke, T; Appelman, H D

    1997-01-01

    Collagenous colitis is a chronic diarrheal disease characterized by a normal or near-normal mucosa endoscopically and microscopic inflammation in the lamina propria, surface epithelial injury and a thick subepithelial collagen layer. The symptoms of collagenous colitis vary in duration and intensity, and long periods of remission have been described, but long-term follow-up data are limited. Our goal was to determine the natural clinical history of collagenous colitis and to determine whether there was a relationship between histopathologic changes and course of disease. Cases were identified at the University of Michigan Hospitals using surgical pathology records before 1992. All charts, including medical records from other hospitals, were reviewed, and a telephone interview was conducted with each locatable patient (pt). Biopsy specimens were reviewed by two pathologists for degree of collagen layer thickness, epithelial damage, and inflammation. There were 31 patients (26 F, 5 M) with a mean age of 66 yr (range 33-83) and a mean duration of symptoms of 5.4 yr at the time of diagnosis. Of the 31 patients, 18 (56%) had some form of arthritis, and 22 (71%) were using NSAIDS regularly at the time of diagnosis. Follow-up interviews were conducted at least 2 yr after diagnosis (mean 3.5 yr, range 2-5 yr) with 27 of 31 patients (3 could not be located, 1 died). Two definable groups of patients were identified: (1) those with either spontaneous or treatment-related symptom resolution (63%), and (2) those with ongoing or intermittent symptoms requiring at least intermittent therapy (37%). There was no significant difference between the two groups with regard to sex, age, associated diseases, and use of medications. Patients with symptom resolution (mean duration 3.1 yr) had been treated with antidiarrheals (6), sulfasalazine (3), discontinuation of NSAIDS (3), reversal of jejunoilial bypass (1), or nothing (4). Those with ongoing symptoms experienced a wide range of

  1. Fate of circulating amino-terminal propeptide of type III procollagen in conscious pigs

    DEFF Research Database (Denmark)

    Jensen, L T; Henriksen, Jens Henrik Sahl; Risteli, J

    1993-01-01

    The amino-terminal propeptide of type III procollagen (PIIINP, M(r) 42,000) is a promising marker for the formation of type III collagen of granulation tissue in experimental and clinical studies. The disposal kinetics of circulating PIIINP is, however, almost unknown. In conscious pigs with a th......The amino-terminal propeptide of type III procollagen (PIIINP, M(r) 42,000) is a promising marker for the formation of type III collagen of granulation tissue in experimental and clinical studies. The disposal kinetics of circulating PIIINP is, however, almost unknown. In conscious pigs...... of the plasma disappearance curve originated from the formation and disappearance of a high and a low molecular weight (MW) fraction as part of the degradation of PIIINP. The high MW fraction (approximately M(r) 90,000) was similar to a previously described, but not further characterized, PIIINP immunoreactive...

  2. ISOCT study of collagen crosslinking of collagen in cancer models (Conference Presentation)

    Science.gov (United States)

    Spicer, Graham; Young, Scott T.; Yi, Ji; Shea, Lonnie D.; Backman, Vadim

    2016-03-01

    The role of extracellular matrix modification and signaling in cancer progression is an increasingly recognized avenue for the progression of the disease. Previous study of field effect carcinogenesis with Inverse Spectroscopic Optical Coherence Tomography (ISOCT) has revealed pronounced changes in the nanoscale-sensitive mass fractal dimension D measured from field effect tissue when compared to healthy tissue. However, the origin of this difference in tissue ultrastructure in field effect carcinogenesis has remained poorly understood. Here, we present findings supporting the idea that enzymatic crosslinking of the extracellular matrix is an effect that presents at the earliest stages of carcinogenesis. We use a model of collagen gel with crosslinking induced by lysyl oxidase (LOXL4) to recapitulate the difference in D previously reported from healthy and cancerous tissue biopsies. Furthermore, STORM imaging of this collagen gel model verifies the morphologic effects of enzymatic crosslinking at length scales as small as 40 nm, close to the previously reported lower length scale sensitivity threshold of 35 nm for ISOCT. Analysis of the autocorrelation function from STORM images of collagen gels and subsequent fitting to the Whittle-Matérn correlation function shows a similar effect of LOXL4 on D from collagen measured with ISOCT and STORM. We extend this to mass spectrometric study of tissue to directly measure concentrations of collagen crosslink residues. The validation of ISOCT as a viable tool for non-invasive rapid quantification of collagen ultrastructure lends it to study other physiological phenomena involving ECM restructuring such as atherosclerotic plaque screening or cervical ripening during pregnancy.

  3. Asporin competes with decorin for collagen binding, binds calcium and promotes osteoblast collagen mineralization

    DEFF Research Database (Denmark)

    Kalamajski, Sebastian; Aspberg, Anders; Lindblom, Karin

    2009-01-01

    , but not by biglycan. We demonstrate that the polyaspartate domain binds calcium and regulates hydroxyapatite formation in vitro. In the presence of asporin, the number of collagen nodules, and mRNA of osteoblastic markers Osterix and Runx2, were increased. Moreover, decorin or the collagen-binding asporin fragment...... biomineralization activity. We also show that asporin can be expressed in Escherichia coli (Rosetta-gami) with correctly positioned cysteine bridges, and a similar system can possibly be used for the expression of other SLRPs (small LRR proteoglycans/proteins)....

  4. Efficient inhibition of fibroblast proliferation and collagen expression by ERK2 siRNAs

    International Nuclear Information System (INIS)

    Li, Fengfeng; Fan, Cunyi; Cheng, Tao; Jiang, Chaoyin; Zeng, Bingfang

    2009-01-01

    Transforming growth factor-β1 and fibroblast growth factor-2 play very important roles in fibroblast proliferation and collagen expression. These processes lead to the formation of joint adhesions through the SMAD and MAPK pathways, in which ERK2 is supposed to be crucial. Based on these assumptions, lentivirus (LV)-mediated small interfering RNAs (siRNAs) targeting ERK2 were used to suppress the proliferation and collagen expression of rat joint adhesion tissue fibroblasts (RJATFs). Among four siRNAs examined, siRNA1 caused an 84% reduction in ERK2 expression (p < 0.01) and was selected as the most efficient siRNA for use in this study. In subsequent experiments, significant downregulation of types I and III collagen were observed by quantitative RT-PCR and Western blot analyses. MTT assays and flow cytometry revealed marked inhibition of RJATF proliferation, but no apoptosis. In conclusion, LV-mediated ERK2 siRNAs may represent novel therapies or drug targets for preventing joint adhesion formation.

  5. Non-invasive quantification of collagen turnover in renal transplant recipients.

    Directory of Open Access Journals (Sweden)

    Elisabeth G D Stribos

    Full Text Available Kidney allograft failure due to chronic injury/rejection remains the main cause of graft loss in renal transplant recipients (RTR. Here, we investigated whether specific biomarkers of extracellular matrix (ECM turnover are associated with allograft function and chronic kidney disease (CKD stage in RTR. Seventy-eight patients who attended the University Medical Center Groningen for a routine check-up after kidney transplantation were enrolled in the study. Plasma and/or 24h-urine samples were collected and specific matrix-metalloproteinase-generated neo-epitope fragments of collagens were measured by enzyme-linked immunosorbent assay. Our results demonstrated that urinary levels of C3M, a marker for collagen type III degradation, correlated with estimated glomerular filtration rate (eGFR; r = 0.58, p<0.0001, with lower levels detected in the urine of patients with advanced CKD. In addition, plasma levels of Pro-C6, a marker for collagen type VI formation, significantly increased with disease progression and correlated with eGFR (r = -0.72, p<0.0001. Conversely, plasma C3M and urinary Pro-C6 levels showed no correlation with renal function. We identified two neo-epitope biomarkers of tissue turnover associated with ECM remodeling and fibrosis that can stratify patients by CKD stage. This is as promising first step towards non-invasive monitoring of ECM turnover in the kidneys.

  6. Type XII and XIV collagens mediate interactions between banded collagen fibers in vitro and may modulate extracellular matrix deformability.

    Science.gov (United States)

    Nishiyama, T; McDonough, A M; Bruns, R R; Burgeson, R E

    1994-11-11

    Type XII and XIV collagens are very large molecules containing three extended globular domains derived from the amino terminus of each alpha chain and an interrupted triple helix. Both collagens are genetically and immunologically unique and have distinct distributions in many tissues. These collagens localize near the surface of banded collagen fibrils. The function of the molecules is unknown. We have prepared a mixture of native type XII and XIV collagens that is free of contaminating proteins by electrophoretic criteria. In addition, we have purified the collagenase-resistant globular domains of type XII or XIV collagens (XII-NC-3 or XIV-NC-3). In this study, we have investigated the effect of intact type XII and XIV and XII-NC-3 or XIV-NC-3 on the interactions between fibroblasts and type I collagen fibrils. We find that both type XII and XIV collagens promote collagen gel contraction mediated by fibroblasts, even in the absence of serum. The activity is present in the NC-3 domains. The effect is dose-dependent and is inhibited by denaturation. The effect of type XII NC-3 is inhibited by the addition of anti-XII antiserum. To elucidate the mechanism underlying this phenomenon, we examined the effect of XII-NC-3 or XIV-NC-3 on deformability of collagen gels by centrifugal force. XII-NC-3 or XIV-NC-3 markedly promotes gel compression after centrifugation. The effect is also inhibited by denaturation, and the activity of type XII-NC3 is inhibited by the addition of anti-XII antiserum. The results indicate that the effect of XII-NC-3 or XIV-NC-3 on collagen gel contraction by fibroblasts is not due to activation of cellular events but rather results from the increase in mobility of hydrated collagen fibrils within the gel. These studies suggest that collagen types XII and XIV may modulate the biomechanical properties of tissues.

  7. Decreased expression of microRNA-29 family in leiomyoma contributes to increased major fibrillar collagen production.

    Science.gov (United States)

    Marsh, Erica E; Steinberg, Marissa L; Parker, J Brandon; Wu, Ju; Chakravarti, Debabrata; Bulun, Serdar E

    2016-09-01

    To determine the expression and function of the microRNA-29 family (miRNA-29a, miRNA-29b, miRNA-29c) in human leiomyoma and myometrium. Basic science experimental design. Academic medical center. Women undergoing surgery for symptomatic uterine fibroids. Overexpression and knockdown of miRNA-29a, miRNA-29b, and miRNA-29c in primary leiomyoma and myometrial cells. [1] Expression of the miRNA-29 family members in vivo in leiomyoma versus myometrium; [2] Major fibrillar collagen (I, II, III) expression in leiomyoma and myometrial cells with manipulation of miRNA-29 species. Members of the miRNA-29 family (29a, 29b, 29c) are all down-regulated in leiomyoma versus myometrium in vivo. The expression of the miRNA-29 family can be successfully modulated in primary leiomyoma and myometrial cells. Overexpression of the miRNA-29 family in leiomyoma cells results in down-regulation of the major fibrillar collagens. Down-regulation of the miRNA-29 species in myometrium results in an increase in collagen type III deposition. The miRNA-29 family is consistently down-regulated in leiomyoma compared to matched myometrial tissue. This down-regulation contributes to the increased collagen seen in leiomyomas versus myometrium. When miRNA-29 members are overexpressed in leiomyoma cells, protein levels of all of the major fibrillar collagens decrease. The miRNA-29 members are potential therapeutic targets in this highly prevalent condition. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  8. Exacerbation of collagen induced arthritis by Fcγ receptor targeted collagen peptide due to enhanced inflammatory chemokine and cytokine production

    Directory of Open Access Journals (Sweden)

    Szarka E

    2012-04-01

    Full Text Available Eszter Szarka1*, Zsuzsa Neer1*, Péter Balogh2, Monika Ádori1, Adrienn Angyal1, József Prechl3, Endre Kiss1,3, Dorottya Kövesdi1, Gabriella Sármay11Department of Immunology, Eötvös Loránd University, 1117 Budapest, 2Department of Immunology and Biotechnology, University of Pécs, Pécs, 3Immunology Research Group of the Hungarian Academy of Science at Eötvös Loránd University, 1117 Budapest, Hungary*These authors contributed equally to this workAbstract: Antibodies specific for bovine type II collagen (CII and Fcγ receptors play a major role in collagen-induced arthritis (CIA, a mouse model of rheumatoid arthritis (RA. Our aim was to clarify the mechanism of immune complex-mediated inflammation and modulation of the disease. CII pre-immunized DBA/1 mice were intravenously boosted with extravidin coupled biotinylated monomeric CII-peptide epitope (ARGLTGRPGDA and its complexes with biotinylated FcγRII/III specific single chain Fv (scFv fragment. Disease scores were monitored, antibody titers and cytokines were determined by ELISA, and binding of complexes was detected by flow cytometry and immune histochemistry. Cytokine and chemokine secretion was monitored by protein profiler microarray. When intravenously administered into collagen-primed DBA/1 mice, both CII-peptide and its complex with 2.4G2 scFv significantly accelerated CIA and increased the severity of the disease, whereas the monomeric peptide and monomeric 2.4G2 scFv had no effect. FcγRII/III targeted CII-peptide complexes bound to marginal zone macrophages and dendritic cells, and significantly elevated the synthesis of peptide-specific IgG2a. Furthermore, CII-peptide containing complexes augmented the in vivo secretion of cytokines, including IL-10, IL-12, IL-17, IL-23, and chemokines (CXCL13, MIP-1, MIP-2. These data indicate that complexes formed by the CII-peptide epitope aggravate CIA by inducing the secretion of chemokines and the IL-12/23 family of pro

  9. Mineralized Collagen: Rationale, Current Status, and Clinical Applications

    Directory of Open Access Journals (Sweden)

    Zhi-Ye Qiu

    2015-07-01

    Full Text Available This paper presents a review of the rationale for the in vitro mineralization process, preparation methods, and clinical applications of mineralized collagen. The rationale for natural mineralized collagen and the related mineralization process has been investigated for decades. Based on the understanding of natural mineralized collagen and its formation process, many attempts have been made to prepare biomimetic materials that resemble natural mineralized collagen in both composition and structure. To date, a number of bone substitute materials have been developed based on the principles of mineralized collagen, and some of them have been commercialized and approved by regulatory agencies. The clinical outcomes of mineralized collagen are of significance to advance the evaluation and improvement of related medical device products. Some representative clinical cases have been reported, and there are more clinical applications and long-term follow-ups that currently being performed by many research groups.

  10. The non-phagocytic route of collagen uptake

    DEFF Research Database (Denmark)

    Madsen, Daniel H; Ingvarsen, Signe; Jürgensen, Henrik J

    2011-01-01

    The degradation of collagens, the most abundant proteins of the extracellular matrix, is involved in numerous physiological and pathological conditions including cancer invasion. An important turnover pathway involves cellular internalization and degradation of large, soluble collagen fragments......, generated by initial cleavage of the insoluble collagen fibers. We have previously observed that in primary mouse fibroblasts, this endocytosis of collagen fragments is dependent on the receptor urokinase plasminogen activator receptor-associated protein (uPARAP)/Endo180. Others have identified additional...... mechanisms of collagen uptake, with different associated receptors, in other cell types. These receptors include β1-integrins, being responsible for collagen phagocytosis, and the mannose receptor. We have now utilized a newly developed monoclonal antibody against uPARAP/Endo180, which down...

  11. Collagen synthesis in human musculoskeletal tissues and skin

    DEFF Research Database (Denmark)

    Babraj, J A; Cuthbertson, D J R; Smith, K

    2005-01-01

    We have developed a direct method for the measurement of human musculoskeletal collagen synthesis on the basis of the incorporation of stable isotope-labeled proline or leucine into protein and have used it to measure the rate of synthesis of collagen in tendon, ligament, muscle, and skin....... In postabsorptive, healthy young men (28 +/- 6 yr) synthetic rates for tendon, ligament, muscle, and skin collagen were 0.046 +/- 0.005, 0.040 +/- 0.006, 0.016 +/- 0.002, and 0.037 +/- 0.003%/h, respectively (means +/- SD). In postabsorptive, healthy elderly men (70 +/- 6 yr) the rate of skeletal muscle collagen...... synthesis is greater than in the young (0.023 +/- 0.002%/h, P collagen are similar to those of mixed skeletal muscle protein in the postabsorptive state, whereas the rate for muscle collagen synthesis is much lower in both young and elderly men...

  12. The decorin sequence SYIRIADTNIT binds collagen type I

    DEFF Research Database (Denmark)

    Kalamajski, Sebastian; Aspberg, Anders; Oldberg, Ake

    2007-01-01

    Decorin belongs to the small leucine-rich repeat proteoglycan family, interacts with fibrillar collagens, and regulates the assembly, structure, and biomechanical properties of connective tissues. The decorin-collagen type I-binding region is located in leucine-rich repeats 5-6. Site......-directed mutagenesis of this 54-residue-long collagen-binding sequence identifies Arg-207 and Asp-210 in leucine-rich repeat 6 as crucial for the binding to collagen. The synthetic peptide SYIRIADTNIT, which includes Arg-207 and Asp-210, inhibits the binding of full-length recombinant decorin to collagen in vitro....... These collagen-binding amino acids are exposed on the exterior of the beta-sheet-loop structure of the leucine-rich repeat. This resembles the location of interacting residues in other leucine-rich repeat proteins....

  13. Comparison of collagen fibre architecture between slow-twitch cranial and fast-twitch caudal parts of broiler M. latissimus dorsi.

    Science.gov (United States)

    Nakamura, Y N; Iwamoto, H; Tabata, S; Ono, Y

    2003-07-01

    1. Collagen fibre architectures of perimysium and endomysium in the slow-twitch cranial and fast-twitch caudal parts of broiler M. latissimus dorsi were compared. 2. Type I and III collagens were distributed in both perimysium and endomysium as indicated by their positive immunohistochemical reactions to polyclonal antibodies. 3. Cells invested by endomysium with no myofibres were larger in the cranial part because of the presence of larger slow-twitch myofibres. The honeycomb structure of endomysium was divided into several parts by thick perimysium. 4. The thick perimysial collagen fibres with parallel fibrils, which were interconnected by the loose reticular fibrils and thin fibres, were more numerous and thicker in the cranial part than the caudal. 5. Thick endomysial sidewall of cells in the cranial part was composed of a rougher reticulum of slightly thicker collagen fibrils compared with the thin sidewall in the caudal part. 6. These results indicated that both perimysial constitutions of collagen fibres and endomysial collagen fibrils had attained much larger growth in the slow-twitch cranial part than the fast-twitch caudal in broiler latissimus dorsi muscle.

  14. Metal stabilization of collagen and de novo designed mimetic peptides

    OpenAIRE

    Parmar, Avanish S.; Xu, Fei; Pike, Douglas H.; Belure, Sandeep V.; Hasan, Nida F.; Drzewiecki, Kathryn E.; Shreiber, David I.; Nanda, Vikas

    2015-01-01

    We explore the design of metal binding sites to modulate triple-helix stability of collagen and collagen-mimetic peptides. Globular proteins commonly utilize metals to connect tertiary structural elements that are well separated in sequence, constraining structure and enhancing stability. It is more challenging to engineer structural metals into fibrous protein scaffolds, which lack the extensive tertiary contacts seen in globular proteins. In the collagen triple helix, the structural adjacen...

  15. Von Willebrand protein binds to extracellular matrices independently of collagen.

    OpenAIRE

    Wagner, D D; Urban-Pickering, M; Marder, V J

    1984-01-01

    Von Willebrand protein is present in the extracellular matrix of endothelial cells where it codistributes with fibronectin and types IV and V collagen. Bacterial collagenase digestion of endothelial cells removed fibrillar collagen, but the pattern of fibronectin and of von Willebrand protein remained undisturbed. Exogenous von Willebrand protein bound to matrices of different cells, whether rich or poor in collagen. von Willebrand protein also decorated the matrix of cells grown in the prese...

  16. Collagenous gastritis: a morphologic and immunohistochemical study of 40 patients.

    Science.gov (United States)

    Arnason, Thomas; Brown, Ian S; Goldsmith, Jeffrey D; Anderson, William; O'Brien, Blake H; Wilson, Claire; Winter, Harland; Lauwers, Gregory Y

    2015-04-01

    Collagenous gastritis is a rare condition defined histologically by a superficial subepithelial collagen layer. This study further characterizes the morphologic spectrum of collagenous gastritis by evaluating a multi-institutional series of 40 patients (26 female and 14 male). The median age at onset was 16 years (range 3-89 years), including 24 patients (60%) under age 18. Twelve patients (30%) had associated celiac disease, collagenous sprue, or collagenous colitis. Hematoxylin and eosin slides were reviewed in biopsies from all patients and tenascin, gastrin, eotaxin, and IgG4/IgG immunohistochemical stains were applied to a subset. The distribution of subepithelial collagen favored the body/fundus in pediatric patients and the antrum in adults. There were increased surface intraepithelial lymphocytes (>25 lymphocytes/100 epithelial cells) in five patients. Three of these patients had associated celiac and/or collagenous sprue/colitis, while the remaining two had increased duodenal lymphocytosis without specific etiology. An eosinophil-rich pattern (>30 eosinophils/high power field) was seen in 21/40 (52%) patients. Seven patients' biopsies demonstrated atrophy of the gastric corpus mucosa. Tenascin immunohistochemistry highlighted the subepithelial collagen in all 21 specimens evaluated and was a more sensitive method of collagen detection in biopsies from two patients with subtle subepithelial collagen. No increased eotaxin expression was identified in 16 specimens evaluated. One of the twenty-three biopsies tested had increased IgG4-positive cells (100/high power field) with an IgG4/IgG ratio of 55%. In summary, collagenous gastritis presents three distinct histologic patterns including a lymphocytic gastritis-like pattern, an eosinophil-rich pattern, and an atrophic pattern. Eotaxin and IgG4 were not elevated enough to implicate these pathways in the pathogenesis. Tenascin immunohistochemistry can be used as a sensitive method of collagen detection.

  17. Variation in the Helical Structure of Native Collagen

    Science.gov (United States)

    2014-02-24

    notochord were obtained in previous studies [4,10,20–22]. The scaled amplitudes of the central, meridional section of each data set were used to...including helical, structure) from rat tail tendon (collagen type I) and lamprey notochord (collagen type II) show several common features (Figure 5). Of...also a possible consequence of the type II collagen notochord samples being stretched, perhaps to a greater extant then the type I tendon samples to aid

  18. [Biophysical principles of collagen cross-linking].

    Science.gov (United States)

    Spörl, E; Raiskup-Wolf, F; Pillunat, L E

    2008-02-01

    The reduced mechanical stability of the cornea in keratoconus or in keratectasia after Lasik may be increased by photooxidative cross-linking of corneal collagen. The biophysical principles are compiled for the safe and effective application of this new treatment method. The setting of the therapy parameters should be elucidated from the absorption behaviour of the cornea. The safety of the method for the endothelium cells and the lens will be discussed. The induced cross-links are shown to be the result of changes in the physico-chemical properties of the cornea. To reach a high absorption of the irradiation energy in the cornea, riboflavin of a concentration of 0.1% and UV light of a wavelength of 370 nm, corresponding to the relative maximum of absorption of riboflavin, were used. An irradiance of 3 mW/cm(2) and an irradiation time of 30 min lead to an increase of the mechanical stiffness. The endothelium cells will be protected due to the high absorption within the cornea, that means the damaging threshold of the endothelium cells will not be reached in a 400 microm thick stroma. As evidence for cross-links we can consider the increase of the biomechanical stiffness, the increased resistance against enzymatic degradation, a higher shrinkage temperature, a lower swelling rate and an increased diameter of collagen fibres. The therapy parameters were tested experimentally and have been proven clinically in the corneal collagen cross-linking. These parameters should be respected to reach a safe cross-linking effect without damage of the adjacent tissues.

  19. Antithrombin III blood test

    Science.gov (United States)

    ... medlineplus.gov/ency/article/003661.htm Antithrombin III blood test To use the sharing features on this page, ... a protein that helps control blood clotting. A blood test can determine the amount of AT III present ...

  20. ELECTRICAL AND THERMODYNAMIC PROPERTIES OF A COLLAGEN SOLUTION

    Directory of Open Access Journals (Sweden)

    Jaromír Štancl

    2017-06-01

    Full Text Available This paper focuses on measurements of the electrical properties, the specific heat capacity and the thermal conductivity of a collagen solution (7.19% mass fraction of native bovine collagen in water. The results of our experiments show that specific electrical conductivity of collagen solution is strongly dependent on temperature. The transition region of collagen to gelatin has been observed from the measured temperature dependence of specific electrical conductivity, and has been confirmed by specific heat capacity measurements by a differential scanning calorimetry.

  1. Marine-derived collagen biomaterials from echinoderm connective tissues

    KAUST Repository

    Ferrario, Cinzia; Leggio, Livio; Leone, Roberta; Di Benedetto, Cristiano; Guidetti, Luca; Coccè , Valentina; Ascagni, Miriam; Bonasoro, Francesco; La Porta, Caterina A.M.; Candia Carnevali, M. Daniela; Sugni, Michela

    2016-01-01

    The use of marine collagens is a hot topic in the field of tissue engineering. Echinoderms possess unique connective tissues (Mutable Collagenous Tissues, MCTs) which can represent an innovative source of collagen to develop collagen barrier-membranes for Guided Tissue Regeneration (GTR). In the present work we used MCTs from different echinoderm models (sea urchin, starfish and sea cucumber) to produce echinoderm-derived collagen membranes (EDCMs). Commercial membranes for GTR or soluble/reassembled (fibrillar) bovine collagen substrates were used as controls. The three EDCMs were similar among each other in terms of structure and mechanical performances and were much thinner and mechanically more resistant than the commercial membranes. Number of fibroblasts seeded on sea-urchin membranes were comparable to the bovine collagen substrates. Cell morphology on all EDCMs was similar to that of structurally comparable (reassembled) bovine collagen substrates. Overall, echinoderms, and sea urchins particularly, are alternative collagen sources to produce efficient GTR membranes. Sea urchins display a further advantage in terms of eco-sustainability by recycling tissues from food wastes.

  2. Collagen-Induced Arthritis: A model for Murine Autoimmune Arthritis.

    Science.gov (United States)

    Pietrosimone, K M; Jin, M; Poston, B; Liu, P

    2015-10-20

    Collagen-induced arthritis (CIA) is a common autoimmune animal model used to study rheumatoid arthritis (RA). The development of CIA involves infiltration of macrophages and neutrophils into the joint, as well as T and B cell responses to type II collagen. In murine CIA, genetically susceptible mice (DBA/1J) are immunized with a type II bovine collagen emulsion in complete Freund's adjuvant (CFA), and receive a boost of type II bovine collagen in incomplete Freund's adjuvant (IFA) 21 days after the first injection. These mice typically develop disease 26 to 35 days after the initial injection. C57BL/6J mice are resistant to arthritis induced by type II bovine collagen, but can develop arthritis when immunized with type II chicken collagen in CFA, and receive a boost of type II chicken collagen in IFA 21 days after the first injection. The concentration of heat-killed Mycobacterium tuberculosis H37RA (MT) in CFA also differs for each strain. DBA/1J mice develop arthritis with 1 mg/ml MT, while C57BL/6J mice require and 3-4 mg/ml MT in order to develop arthritis. CIA develops slowly in C57BL/6J mice and cases of arthritis are mild when compared to DBA/1J mice. This protocol describes immunization of DBA/1J mice with type II bovine collagen and the immunization of C57BL/6J mice with type II chicken collagen.

  3. Collagen-Induced Arthritis: A model for Murine Autoimmune Arthritis

    OpenAIRE

    Pietrosimone, K. M.; Jin, M.; Poston, B.; Liu, P.

    2015-01-01

    Collagen-induced arthritis (CIA) is a common autoimmune animal model used to study rheumatoid arthritis (RA). The development of CIA involves infiltration of macrophages and neutrophils into the joint, as well as T and B cell responses to type II collagen. In murine CIA, genetically susceptible mice (DBA/1J) are immunized with a type II bovine collagen emulsion in complete Freund’s adjuvant (CFA), and receive a boost of type II bovine collagen in incomplete Freund’s adjuvant (IFA) 21 days aft...

  4. Degradation of type IV collagen by neoplastic human skin fibroblasts

    International Nuclear Information System (INIS)

    Sheela, S.; Barrett, J.C.

    1985-01-01

    An assay for the degradation of type IV (basement membrane) collagen was developed as a biochemical marker for neoplastic cells from chemically transformed human skin fibroblasts. Type IV collagen was isolated from basement membrane of Syrian hamster lung and type I collagen was isolated from rat tails; the collagens were radioactively labelled by reductive alkylation. The abilities of normal (KD) and chemically transformed (Hut-11A) human skin fibroblasts to degrade the collagens were studied. A cell-associated assay was performed by growing either normal or transformed cells in the presence of radioactively labelled type IV collagen and measuring the released soluble peptides in the medium. This assay also demonstrated that KD cells failed to synthesize an activity capable of degrading type IV collagen whereas Hut-11A cells degraded type IV collagen in a linear manner for up to 4 h. Human serum at very low concentrations, EDTA and L-cysteine inhibited the enzyme activity, whereas protease inhibitors like phenylmethyl sulfonyl fluoride, N-ethyl maleimide or soybean trypsin inhibitor did not inhibit the enzyme from Hut-11A cells. These results suggest that the ability to degrade specifically type IV collagen may be an important marker for neoplastic human fibroblasts and supports a role for this collagenase in tumor cell invasion

  5. Stabilization and anomalous hydration of collagen fibril under heating.

    Directory of Open Access Journals (Sweden)

    Sasun G Gevorkian

    Full Text Available BACKGROUND: Type I collagen is the most common protein among higher vertebrates. It forms the basis of fibrous connective tissues (tendon, chord, skin, bones and ensures mechanical stability and strength of these tissues. It is known, however, that separate triple-helical collagen macromolecules are unstable at physiological temperatures. We want to understand the mechanism of collagen stability at the intermolecular level. To this end, we study the collagen fibril, an intermediate level in the collagen hierarchy between triple-helical macromolecule and tendon. METHODOLOGY/PRINCIPAL FINDING: When heating a native fibril sample, its Young's modulus decreases in temperature range 20-58°C due to partial denaturation of triple-helices, but it is approximately constant at 58-75°C, because of stabilization by inter-molecular interactions. The stabilization temperature range 58-75°C has two further important features: here the fibril absorbs water under heating and the internal friction displays a peak. We relate these experimental findings to restructuring of collagen triple-helices in fibril. A theoretical description of the experimental results is provided via a generalization of the standard Zimm-Bragg model for the helix-coil transition. It takes into account intermolecular interactions of collagen triple-helices in fibril and describes water adsorption via the Langmuir mechanism. CONCLUSION/SIGNIFICANCE: We uncovered an inter-molecular mechanism that stabilizes the fibril made of unstable collagen macromolecules. This mechanism can be relevant for explaining stability of collagen.

  6. Discoidin Domain Receptor 1 Mediates Myosin-Dependent Collagen Contraction

    Directory of Open Access Journals (Sweden)

    Nuno M. Coelho

    2017-02-01

    Full Text Available Discoidin domain receptor 1 (DDR1 is a tyrosine kinase collagen adhesion receptor that mediates cell migration through association with non-muscle myosin IIA (NMIIA. Because DDR1 is implicated in cancer fibrosis, we hypothesized that DDR1 interacts with NMIIA to enable collagen compaction by traction forces. Mechanical splinting of rat dermal wounds increased DDR1 expression and collagen alignment. In periodontal ligament of DDR1 knockout mice, collagen mechanical reorganization was reduced >30%. Similarly, cultured cells with DDR1 knockdown or expressing kinase-deficient DDR1d showed 50% reduction of aligned collagen. Tractional remodeling of collagen was dependent on DDR1 clustering, activation, and interaction of the DDR1 C-terminal kinase domain with NMIIA filaments. Collagen remodeling by traction forces, DDR1 tyrosine phosphorylation, and myosin light chain phosphorylation were increased on stiff versus soft substrates. Thus, DDR1 clustering, activation, and interaction with NMIIA filaments enhance the collagen tractional remodeling that is important for collagen compaction in fibrosis.

  7. Tendon collagen synthesis declines with immobilization in elderly humans

    DEFF Research Database (Denmark)

    Dideriksen, Kasper; Boesen, Anders P; Reitelseder, Søren

    2017-01-01

    -80 yr) were randomly assigned to NSAIDs (ibuprofen 1,200 mg/day; Ibu) or placebo (Plc). One lower limb was immobilized in a cast for 2 wk and retrained for 6 wk. Tendon collagen protein synthesis, mechanical properties, size, expression of genes related to collagen turnover and remodeling, and signal...... intensity (from magnetic resonance imaging) were investigated. Tendon collagen synthesis decreased (P ... immobilization in both groups, whereas scleraxis mRNA decreased with inactivity in the Plc group only (P collagen protein synthesis decreased after 2 wk of immobilization, whereas tendon stiffness and modulus were only marginally reduced, and NSAIDs had no influence upon this...

  8. The collagen receptor uPARAP/Endo180

    DEFF Research Database (Denmark)

    Engelholm, Lars H; Ingvarsen, Signe; Jürgensen, Henrik J

    2009-01-01

    The uPAR-associated protein (uPARAP/Endo180), a type-1 membrane protein belonging to the mannose receptor family, is an endocytic receptor for collagen. Through this endocytic function, the protein takes part in a previously unrecognized mechanism of collagen turnover. uPARAP/Endo180 can bind...... and internalize both intact and partially degraded collagens. In some turnover pathways, the function of the receptor probably involves an interplay with certain matrix-degrading proteases whereas, in other physiological processes, redundant mechanisms involving both endocytic and pericellular collagenolysis seem...... in collagen breakdown seems to be involved in invasive tumor growth Udgivelsesdato: 2009...

  9. Marine-derived collagen biomaterials from echinoderm connective tissues

    KAUST Repository

    Ferrario, Cinzia

    2016-03-31

    The use of marine collagens is a hot topic in the field of tissue engineering. Echinoderms possess unique connective tissues (Mutable Collagenous Tissues, MCTs) which can represent an innovative source of collagen to develop collagen barrier-membranes for Guided Tissue Regeneration (GTR). In the present work we used MCTs from different echinoderm models (sea urchin, starfish and sea cucumber) to produce echinoderm-derived collagen membranes (EDCMs). Commercial membranes for GTR or soluble/reassembled (fibrillar) bovine collagen substrates were used as controls. The three EDCMs were similar among each other in terms of structure and mechanical performances and were much thinner and mechanically more resistant than the commercial membranes. Number of fibroblasts seeded on sea-urchin membranes were comparable to the bovine collagen substrates. Cell morphology on all EDCMs was similar to that of structurally comparable (reassembled) bovine collagen substrates. Overall, echinoderms, and sea urchins particularly, are alternative collagen sources to produce efficient GTR membranes. Sea urchins display a further advantage in terms of eco-sustainability by recycling tissues from food wastes.

  10. Fabrication of homobifunctional crosslinker stabilized collagen for biomedical application

    International Nuclear Information System (INIS)

    Lakra, Rachita; Kiran, Manikantan Syamala; Sai, Korrapati Purna

    2015-01-01

    Collagen biopolymer has found widespread application in the field of tissue engineering owing to its excellent tissue compatibility and negligible immunogenicity. Mechanical strength and enzymatic degradation of the collagen necessitates the physical and chemical strength enhancement. One such attempt deals with the understanding of crosslinking behaviour of EGS (ethylene glycol-bis (succinic acid N-hydroxysuccinimide ester)) with collagen to improve the physico-chemical properties. The incorporation of a crosslinker during fibril formation enhanced the thermal and mechanical stability of collagen. EGS crosslinked collagen films exhibited higher denaturation temperature (T d ) and the residue left after thermogravimetric analysis was about 16  ±  5.2%. Mechanical properties determined by uniaxial tensile tests showed a threefold increase in tensile strength and Young’s modulus at higher concentration (100 μM). Water uptake capacity reduced up to a moderate extent upon crosslinking which is essential for the transport of nutrients to the cells. Cell viability was found to be 100% upon treatment with 100 μM EGS whereas only 30% viability could be observed with glutaraldehyde. Rheological studies of crosslinked collagen showed an increase in shear stress and shear viscosity at 37 °C. Crosslinking with EGS resulted in the formation of a uniform fibrillar network. Trinitrobenzene sulfonate (TNBS) assay confirmed that EGS crosslinked collagen by forming a covalent interaction with ε-amino acids of collagen. The homobifunctional crosslinker used in this study enhanced the effectiveness of collagen as a biomaterial for biomedical application. (paper)

  11. Small-bowel permeability in collagenous colitis

    DEFF Research Database (Denmark)

    Wildt, Signe; Madsen, Jan L; Rumessen, Jüri J

    2006-01-01

    Collagenous colitis (CC) is a chronic inflammatory bowel disease that affects the colon. However, some patients with CC present with accompanying pathologic small-bowel manifestations such as coeliac disease, defects in bile acid absorption and histopathologic changes in small-intestinal biopsies......, indicating that CC is a pan-intestinal disease. In small-intestinal disease, the intestinal barrier function may be impaired, and the permeability of the small intestine altered. The purpose of this research was to study small-bowel function in patients with CC as expressed by intestinal permeability....

  12. Prediction of collagen orientation in articular cartilage by a collagen remodeling algorithm

    NARCIS (Netherlands)

    Wilson, W.; Driessen, N.J.B.; Donkelaar, van C.C.; Ito, K.

    2006-01-01

    Tissue engineering is a promising method to treat damaged cartilage. So far it has not been possible to create tissue-engineered cartilage with an appropriate structural organization. It is envisaged that cartilage tissue engineering will significantly benefit from knowledge of how the collagen

  13. Comparison of thermal properties of fish collagen and bovine collagen in the temperature range 298-670K.

    Science.gov (United States)

    Gauza-Włodarczyk, Marlena; Kubisz, Leszek; Mielcarek, Sławomir; Włodarczyk, Dariusz

    2017-11-01

    The increased interest in fish collagen is a consequence of the risk of exposure to Creutzfeld-Jacob disease (CJD) and the bovine spongiform encephalopathy (BSE), whose occurrence is associated with prions carried by bovine collagen. Collagen is the main biopolymer in living organisms and the main component of the skin and bones. Until the discovery of the BSE, bovine collagen had been widely used. The BSE epidemic increased the interest in new sources of collagen such as fish skin collagen (FSC) and its properties. Although the thermal properties of collagen originating from mammals have been well described, less attention has been paid to the thermal properties of FSC. Denaturation temperature is a particularly important parameter, depending on the collagen origin and hydration level. In the reported experiment, the free water and bound water release processes along with thermal denaturation process were studied by means of the differential scanning calorimetry (DSC). Measurements were carried out using a DSC 7 instrument (Elmer-Perkin), in the temperature range 298-670K. The study material was FSC derived by acidic hydration method. The bovine Achilles tendon (BAT) collagen type I was used as the control material. The thermograms recorded revealed both, exothermic and endothermic peaks. For both materials, the peaks in the temperature range of 330-360K were assigned to the release of free water and bound water. The denaturation temperatures of FSC and BAT collagen were determined as 420K and 493K, respectively. Thermal decomposition process was observed at about 500K for FSC and at about 510K for BAT collagen. These results show that FSC is less resistant to high temperature than BAT collagen. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Markers of Collagen Remodeling Detect Clinically Significant Fibrosis in Chronic Hepatitis C Patients

    DEFF Research Database (Denmark)

    Nielsen, Mette J; Kazankov, Konstantin; Leeming, Diana J

    2015-01-01

    as potential biomarkers for clinically significant and advanced fibrosis. METHODS: Specific protein fragments of matrix metalloprotease degraded type I, III, IV and VI collagen (C1M, C3M, C4M, C6M) and type III and IV collagen formation (Pro-C3 and P4NP7S) were assessed in plasma from 403 chronic hepatitis C...... patients by specific ELISAs. Patients were stratified according to Metavir Fibrosis stage; F0 (n = 46), F1 (n = 161), F2 (n = 95), F3 (n = 44) and F4 (n = 33) based on liver biopsy. RESULTS: Pro-C3 was significantly elevated in patients with significant fibrosis (≥F2) compared to F0-F1 (p... the markers C3M, C4M, C6M and P4NP7S were significantly elevated in patients with advanced fibrosis (≥F3) compared to F0-F2 (pC1M showed no difference between fibrosis stages. Using Receiver Operating Characteristics analysis, the best marker for detecting ≥F2 and ≥F3 was Pro-C3 with AUC = 0...

  15. Ameloblasts express type I collagen during amelogenesis.

    Science.gov (United States)

    Assaraf-Weill, N; Gasse, B; Silvent, J; Bardet, C; Sire, J Y; Davit-Béal, T

    2014-05-01

    Enamel and enameloid, the highly mineralized tooth-covering tissues in living vertebrates, are different in their matrix composition. Enamel, a unique product of ameloblasts, principally contains enamel matrix proteins (EMPs), while enameloid possesses collagen fibrils and probably receives contributions from both odontoblasts and ameloblasts. Here we focused on type I collagen (COL1A1) and amelogenin (AMEL) gene expression during enameloid and enamel formation throughout ontogeny in the caudate amphibian, Pleurodeles waltl. In this model, pre-metamorphic teeth possess enameloid and enamel, while post-metamorphic teeth possess enamel only. In first-generation teeth, qPCR and in situ hybridization (ISH) on sections revealed that ameloblasts weakly expressed AMEL during late-stage enameloid formation, while expression strongly increased during enamel deposition. Using ISH, we identified COL1A1 transcripts in ameloblasts and odontoblasts during enameloid formation. COL1A1 expression in ameloblasts gradually decreased and was no longer detected after metamorphosis. The transition from enameloid-rich to enamel-rich teeth could be related to a switch in ameloblast activity from COL1A1 to AMEL synthesis. P. waltl therefore appears to be an appropriate animal model for the study of the processes involved during enameloid-to-enamel transition, especially because similar events probably occurred in various lineages during vertebrate evolution.

  16. Postnatal development of collagen structure in ovine articular cartilage

    Directory of Open Access Journals (Sweden)

    Kranenbarg Sander

    2010-06-01

    Full Text Available Abstract Background Articular cartilage (AC is the layer of tissue that covers the articulating ends of the bones in diarthrodial joints. Across species, adult AC shows an arcade-like structure with collagen predominantly perpendicular to the subchondral bone near the bone, and collagen predominantly parallel to the articular surface near the articular surface. Recent studies into collagen fibre orientation in stillborn and juvenile animals showed that this structure is absent at birth. Since the collagen structure is an important factor for AC mechanics, the absence of the adult Benninghoff structure has implications for perinatal AC mechanobiology. The current objective is to quantify the dynamics of collagen network development in a model animal from birth to maturity. We further aim to show the presence or absence of zonal differentiation at birth, and to assess differences in collagen network development between different anatomical sites of a single joint surface. We use quantitative polarised light microscopy to investigate properties of the collagen network and we use the sheep (Ovis aries as our model animal. Results Predominant collagen orientation is parallel to the articular surface throughout the tissue depth for perinatal cartilage. This remodels to the Benninghoff structure before the sheep reach sexual maturity. Remodelling of predominant collagen orientation starts at a depth just below the future transitional zone. Tissue retardance shows a minimum near the articular surface at all ages, which indicates the presence of zonal differentiation at all ages. The absolute position of this minimum does change between birth and maturity. Between different anatomical sites, we find differences in the dynamics of collagen remodelling, but no differences in adult collagen structure. Conclusions The collagen network in articular cartilage remodels between birth and sexual maturity from a network with predominant orientation parallel to the

  17. Structure and characteristics of acid and pepsin-solubilized collagens from the skin of cobia (Rachycentron canadum).

    Science.gov (United States)

    Zeng, Shaokui; Yin, Juanjuan; Yang, Shuqi; Zhang, Chaohua; Yang, Ping; Wu, Wenlong

    2012-12-01

    Acid-solubilized collagen (ASC) and pepsin-solubilized collagen (PSC) were extracted from the skin of cobia (Rachycentron canadum). The yields of ASC and PSC were 35.5% and 12.3%, respectively. Based on the protein patterns and carboxymethyl-cellulose chromatography, ASC and PSC were composed of α1α2α3 heterotrimers and were characterised as type I collagen with no disulfide bond. Their amounts of imino acids were 203 and 191 residues per 1000 residues, respectively. LC-MS/MS analysis demonstrated the high sequences similarities of ASC and PSC. Fourier transform infrared spectroscopy spectra showed that the amide I, II and III peaks of PSC were obtained at a lower wave number compared with ASC. The thermal denaturation temperatures of ASC and PSC, as measured by viscometry, were 34.62 and 33.97°C, respectively. The transition temperatures (T(max)) were 38.17 and 36.03°C, respectively, as determined by differential scanning calorimetry (DSC). Both collagens were soluble at acidic pH and below 2% (w/v) NaCl concentration. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Preparation and characterization of porous crosslinked collagenous matrices containing bioavailable chondroitin sulphate

    NARCIS (Netherlands)

    Pieper, J.S.; Oosterhof, A.; Dijkstra, Pieter J.; Veerkamp, J.H.; van Kuppevelt, T.H.

    1999-01-01

    Porous collagen matrices with defined physical, chemical and biological characteristics are interesting materials for tissue engineering. Attachment of glycosaminoglycans (GAGs) may add to these characteristics and valorize collagen. In this study, porous type I collagen matrices were crosslinked

  19. Assessment and characterization of degradation effect for the varied degrees of ultra-violet radiation onto the collagen-bonded polypropylene non-woven fabric surfaces.

    Science.gov (United States)

    Tyan, Yu-Chang; Liao, Jiunn-Der; Klauser, Ruth; Wu, Ie-Der; Weng, Chih-Chiang

    2002-01-01

    Exposure to ultra-violet (UV)-C radiation is a frequently used method to prevent bacteria from invasion of blood-contact biomedical products. Potential damage induced by UV radiation to collagen is of concern due to the decay of bioactivity, considerably correlated with structural alterations. Our current investigation studies the collagen-bonded non-woven polypropylene (PP) fabric surface. In this experiment, antenna-coupling microwave plasma is utilized to activate PP fabric and then the sample is grafted with acrylic acid (AAc). Type III collagen is immobilized by using water soluble 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide as coupling agent. The collagen-bonded samples with sample temperature ca. 4 degrees C are then exposed to UV-254nm radiation for different time intervals. By using fourier-transformed infrared with attenuated total reflection (FTIR-ATR) and XPS (X-ray photoelectron spectroscopy), we examine the chemical structures of samples with different treatments. Coomassie brilliant blue G250 method is utilized to quantify the immobilized collagen on the PP fabric surfaces. Blood-clotting effects are evaluated by activated partial thromboplastin time, thrombin time, and fibrinogen concentration tests. By means of cell counter and scanning electron microscopy we count red blood cells and platelets adhesion in the modified porous matrix. Our experimental results have demonstrated that with pAAc-grafting of ca. 173 microg cm(-2) and immobilized collagen of 80.5+/-4.7 microg cm(-2), for human plasma incubated samples of various intervals of UV-254 nm radiation, fibrinogen concentration decreases in human plasma, while platelets and red blood cells adhesions increase before UV radiation. However, the required time for thrombination shows significant change for UV radiation exposure of less than 20 h (alpha = 0.05). The decay of bioactivity for the UV-irradiated, collagen-bonded surfaces is thus evaluated. Surface analyses indicate that the decrease of

  20. Effect of Mechanical Stretching of the Skin on Collagen Fibril ...

    African Journals Online (AJOL)

    Stabilization of collagen fibres during development and through growth to maturation has now become fairly documented. In vitro effect of mechanical stretching of ratsf skin on oxidative deamination of ε-NH2-groups of lysine and hydroxylysine, and functional properties of its type . collagen were studied. Experiments were ...

  1. Electrophoretic mobility patterns of collagen following laser welding

    Science.gov (United States)

    Bass, Lawrence S.; Moazami, Nader; Pocsidio, Joanne O.; Oz, Mehmet C.; LoGerfo, Paul; Treat, Michael R.

    1991-06-01

    Clinical application of laser vascular anastomosis in inhibited by a lack of understanding of its mechanism. Whether tissue fusion results from covalent or non-covalent bonding of collagen and other structural proteins is unknown. We compared electrophoretic mobility of collagen in laser treated and untreated specimens of rat tail tendon (>90% type I collagen) and rabbit aorta. Welding was performed, using tissue shrinkage as the clinical endpoint, using the 808 nm diode laser (power density 14 watts/cm2) and topical indocyanine green dye (max absorption 805 nm). Collagen was extracted with 8 M urea (denaturing), 0.5 M acetic acid (non-denaturing) and acetic acid/pepsin (cleaves non- helical protein). Mobility patterns on gel electrophoresis (SDS-PAGE) after urea or acetic acid extraction were identical in the lasered and control tendon and vessel (confirmed by optical densitometry), revealing no evidence of formation of novel covalent bonds. Alpha and beta band intensity was diminished in pepsin incubated lasered specimens compared with controls (optical density ratio 0.00 +/- 9 tendon, 0.65 +/- 0.12 aorta), indicating the presence of denatured collagen. With the laser parameters used, collagen is denatured without formation of covalent bonds, suggesting that non-covalent interaction between denatured collagen molecules may be responsible for the weld. Based on this mechanism, welding parameters can be chosen which produce collagen denaturation without cell death.

  2. Effects of recombinant human collagen VI from Escherichia coli on ...

    African Journals Online (AJOL)

    Jane

    2011-07-20

    Jul 20, 2011 ... In this study, we reported the cloning and over expression of a gene coding for human collagen peptide. (CP6) in Escherichia coli and investigated the protective effects of CP6 on UVA-irradiated human skin fibroblasts cells. The collagen peptide (CP6) was highly soluble and the expression level was.

  3. Changes in collagen synthesis and degradation during skeletal muscle growth

    International Nuclear Information System (INIS)

    Laurent, G.J.; McAnulty, R.J.; Gibson, J.

    1985-01-01

    The changes in collagen metabolism during skeletal muscle growth were investigated by measuring rates of synthesis and degradation during stretch-induced hypertrophy of the anterior latissimus dorsi muscle of the adult chicken (Gallus domesticus). Synthesis rates were obtained from the uptake of tritiated proline injected intravenously with a flooding dose of unlabeled proline. Degradation of newly synthesized and ''mature'' collagen was estimated from the amount of hydroxyproline in the free pool as small molecular weight moieties. In normal muscle, the synthesis rate was 1.1 +/- 0.3%/day, with 49 +/- 7% of the newly produced collagen degraded rapidly after synthesis. During hypertrophy there was an increase of about fivefold in the rate of synthesis (P less than 0.01), a 60% decrease in the rate of degradation of newly synthesized collagen (P less than 0.02), and an increase of about fourfold in the amount of degradation of mature collagen (P less than 0.01). These results suggest an important role for degradative as well as synthetic processes in the regulation of collagen mass. They indicate that enhanced degradation of mature collagen is required for muscle growth and suggest a physiological role for the pathway whereby in normal muscle, a large proportion of newly produced collagen is rapidly degraded

  4. Chitosan Cross-linked Reconstituted Amniotic Collagen Membrane ...

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Chitosan Cross-linked Reconstituted Amniotic Collagen Membrane – An Excellent Cell Substratum. The KERATINOCYTE proliferation and Differentiation into multiple layers is due to the presence of type - IV collagen in the amnion. Cultured FIBROBLASTS had good ...

  5. The collagen microfibril model, a tool for biomaterials scientists

    Science.gov (United States)

    Animal hides, a major byproduct of the meat industry, are a rich source of collagen, a structural protein of the extracellular matrix that gives strength and form to the skin, tendons and bones of mammals. The structure of fibrous collagen, a long triple helix that self-associates in a staggered arr...

  6. Postnatal development of collagen structure in ovine articular cartilage

    NARCIS (Netherlands)

    Turnhout, van M.C.; Schipper, H.; Engel, B.; Buist, W.; Kranenbarg, S.; Leeuwen, van J.L.

    2010-01-01

    Background Articular cartilage (AC) is the layer of tissue that covers the articulating ends of the bones in diarthrodial joints. Across species, adult AC shows an arcade-like structure with collagen predominantly perpendicular to the subchondral bone near the bone, and collagen predominantly

  7. Postnatal development of collagen structure in ovine articular cartilage

    NARCIS (Netherlands)

    Turnhout, van M.C.; Schipper, H.; Engel, B.; Buist, W.; Kranenbarg, S.; Leeuwen, van J.L.

    2010-01-01

    BACKGROUND:Articular cartilage (AC) is the layer of tissue that covers the articulating ends of the bones in diarthrodial joints. Across species, adult AC shows an arcade-like structure with collagen predominantly perpendicular to the subchondral bone near the bone, and collagen predominantly

  8. Collagen levels are normalized after decompression of experimentally obstructed colon

    DEFF Research Database (Denmark)

    Rehn, Martin; Ågren, Sven Per Magnus; Syk, I

    2011-01-01

    Our aim was to define the dynamics in collagen concentrations in the large bowel wall following decompression of experimental obstruction.......Our aim was to define the dynamics in collagen concentrations in the large bowel wall following decompression of experimental obstruction....

  9. Fish collagen is an important panallergen in the Japanese population.

    Science.gov (United States)

    Kobayashi, Y; Akiyama, H; Huge, J; Kubota, H; Chikazawa, S; Satoh, T; Miyake, T; Uhara, H; Okuyama, R; Nakagawara, R; Aihara, M; Hamada-Sato, N

    2016-05-01

    Collagen was identified as a fish allergen in early 2000s. Although its allergenic potential has been suggested to be low, risks associated with collagen as a fish allergen have not been evaluated to a greater extent. In this study, we aimed to clarify the importance of collagen as a fish allergen. Our results showed that 50% of Japanese patients with fish allergy had immunoglobulin E (IgE) against mackerel collagen, whereas 44% had IgE against mackerel parvalbumin. IgE inhibition assay revealed high cross-reactivity of mackerel collagen to 22 fish species (inhibition rates: 87-98%). Furthermore, a recently developed allergy test demonstrated that collagen triggered IgE cross-linking on mast cells. These data indicate that fish collagen is an important and very common panallergen in fish consumed in Japan. The high rate of individuals' collagen allergy may be attributable to the traditional Japanese custom of raw fish consumption. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Preparation and structure characterization of soluble bone collagen ...

    African Journals Online (AJOL)

    In this study, G-25 gel chromatography, X-diffraction, scanning electron microscopy (SEM), UV and Fourier transform infrared spectroscopy (FTIR) were used to analyze soluble collagen peptides chelating calcium. Collagen peptide hydrolysis can be divided into four components using G-25 gel chromatography.

  11. Penta-fibrillar assembly: A Building block collagen based materials

    Indian Academy of Sciences (India)

    There is a smartness in the way the penta-fibrils behave in collagen based biomaterials. It is one of the intriguing nano material with a size of about 4 nano meter diagonal size. There are several intermolecular forces that participate in the penta fibrillar assembly, which derive importance in smart behavior of collagen.

  12. Collagenous colitis as a possible cause of toxic megacolon.

    LENUS (Irish Health Repository)

    Fitzgerald, S C

    2009-03-01

    Collagenous colitis is a microscopic colitis characterized by normal appearing colonic mucosa on endoscopy. It is regarded as a clinically benign disease which rarely results in serious complications. We report a case of toxic megacolon occurring in a patient with collagenous colitis. This is the first reported case of toxic megacolon occurring in this subset of patients.

  13. Collagen synthesis in CBA mouse heart after total thoracic irradiation

    International Nuclear Information System (INIS)

    Murray, J.C.; Parkins, C.S.; Institute of Cancer Research, Sutton

    1988-01-01

    CBA mice were irradiated to the whole thorax with single doses of 240 kVp X-rays in the dose range 8-16 Gy. Collagen and total protein synthesis rates in the heart were measured at 2-monthly intervals using a radio-isotope incorporation techniques. Doses of 10 Gy or greater caused a slight increase in collagen synthesis, followed by significantly reduced collagen synthesis by 16 weeks or longer after treatment. The depression in synthesis appeared correspondingly earlier with increasing dose. Total protein synthesis in heart followed similar patterns although changes were not statistically significant, indicating that the changes reflected alterations to collagen synthesis specifally, and not protein synthesis in geneal. Total hydroxyproline measurements showed no significant changes in heart collagen at any time as a result of X-irradiation. 18 refs.; 7 figs

  14. Second-harmonic generation imaging of collagen in ancient bone.

    Science.gov (United States)

    Thomas, B; McIntosh, D; Fildes, T; Smith, L; Hargrave, F; Islam, M; Thompson, T; Layfield, R; Scott, D; Shaw, B; Burrell, C L; Gonzalez, S; Taylor, S

    2017-12-01

    Second-harmonic generation imaging (SHG) captures triple helical collagen molecules near tissue surfaces. Biomedical research routinely utilizes various imaging software packages to quantify SHG signals for collagen content and distribution estimates in modern tissue samples including bone. For the first time using SHG, samples of modern, medieval, and ice age bones were imaged to test the applicability of SHG to ancient bone from a variety of ages, settings, and taxa. Four independent techniques including Raman spectroscopy, FTIR spectroscopy, radiocarbon dating protocols, and mass spectrometry-based protein sequencing, confirm the presence of protein, consistent with the hypothesis that SHG imaging detects ancient bone collagen. These results suggest that future studies have the potential to use SHG imaging to provide new insights into the composition of ancient bone, to characterize ancient bone disorders, to investigate collagen preservation within and between various taxa, and to monitor collagen decay regimes in different depositional environments.

  15. Second-harmonic generation imaging of collagen in ancient bone

    Directory of Open Access Journals (Sweden)

    B. Thomas

    2017-12-01

    Full Text Available Second-harmonic generation imaging (SHG captures triple helical collagen molecules near tissue surfaces. Biomedical research routinely utilizes various imaging software packages to quantify SHG signals for collagen content and distribution estimates in modern tissue samples including bone. For the first time using SHG, samples of modern, medieval, and ice age bones were imaged to test the applicability of SHG to ancient bone from a variety of ages, settings, and taxa. Four independent techniques including Raman spectroscopy, FTIR spectroscopy, radiocarbon dating protocols, and mass spectrometry-based protein sequencing, confirm the presence of protein, consistent with the hypothesis that SHG imaging detects ancient bone collagen. These results suggest that future studies have the potential to use SHG imaging to provide new insights into the composition of ancient bone, to characterize ancient bone disorders, to investigate collagen preservation within and between various taxa, and to monitor collagen decay regimes in different depositional environments.

  16. Collagen matrix as a tool in studying fibroblastic cell behavior.

    Science.gov (United States)

    Kanta, Jiří

    2015-01-01

    Type I collagen is a fibrillar protein, a member of a large family of collagen proteins. It is present in most body tissues, usually in combination with other collagens and other components of extracellular matrix. Its synthesis is increased in various pathological situations, in healing wounds, in fibrotic tissues and in many tumors. After extraction from collagen-rich tissues it is widely used in studies of cell behavior, especially those of fibroblasts and myofibroblasts. Cells cultured in a classical way, on planar plastic dishes, lack the third dimension that is characteristic of body tissues. Collagen I forms gel at neutral pH and may become a basis of a 3D matrix that better mimics conditions in tissue than plastic dishes.

  17. Stability and cellular responses to fluorapatite-collagen composites.

    Science.gov (United States)

    Yoon, Byung-Ho; Kim, Hae-Won; Lee, Su-Hee; Bae, Chang-Jun; Koh, Young-Hag; Kong, Young-Min; Kim, Hyoun-Ee

    2005-06-01

    Fluorapatite (FA)-collagen composites were synthesized via a biomimetic coprecipitation method in order to improve the structural stability and cellular responses. Different amounts of ammonium fluoride (NH4F), acting as a fluorine source for FA, were added to the precipitation of the composites. The precipitated composites were freeze-dried and isostatically pressed in a dense body. The added fluorine was incorporated nearly fully into the apatite structure (fluoridation), and a near stoichiometric FA-collagen composite was obtained with complete fluoridation. The freeze-dried composites had a typical biomimetic network, consisting of collagen fibers and precipitates of nano-sized apatite crystals. The human osteoblast-like cells on the FA-collagen composites exhibited significantly higher proliferation and differentiation (according to alkaline phosphatase activity) than those on the hydroxyapatite-collagen composite. These enhanced osteoblastic cell responses were attributed to the fluorine release and the reduced dissolution rate.

  18. Cervical Collagen Concentration within Fifteen Months after Delivery

    DEFF Research Database (Denmark)

    Sundtoft, Iben; Uldbjerg, Niels; Sommer, Steffe

    2011-01-01

    OBJECTIVE: Cervical collagen concentration decreases during pregnancy. The increased risk of preterm birth following a short interpregnancy interval may be explained by an incomplete remodeling of the cervix. The objective of this study was to describe the changes in cervical collagen concentration...... over 15 months following delivery. METHODS: The collagen concentrations were determined in cervical biopsies obtained from 15 women at 3, 6, 9, 12, and 15 months after delivery. RESULTS: The mean cervical collagen concentrations were 50, 59, 63, 65, and 65 % of dry weight (SD 4.2 – 6.5). This increase...... was statistically significant until month 9, but not between months 9 and 12. CONCLUSIONS: Low collagen concentrations in the uterine cervix may contribute to the association between a short interpregnancy interval and preterm birth....

  19. Mechanical response of collagen molecule under hydrostatic compression

    International Nuclear Information System (INIS)

    Saini, Karanvir; Kumar, Navin

    2015-01-01

    Proteins like collagen are the basic building blocks of various body tissues (soft and hard). Collagen molecules find their presence in the skeletal system of the body where they bear mechanical loads from different directions, either individually or along with hydroxy-apatite crystals. Therefore, it is very important to understand the mechanical behavior of the collagen molecule which is subjected to multi-axial state of loading. The estimation of strains of collagen molecule along different directions resulting from the changes in hydrostatic pressure magnitude, can provide us new insights into its mechanical behavior. In the present work, full atomistic simulations have been used to study global (volumetric) as well as local (along different directions) mechanical properties of the hydrated collagen molecule which is subjected to different hydrostatic pressure magnitudes. To estimate the local mechanical properties, the strains of collagen molecule along its longitudinal and transverse directions have been acquired at different hydrostatic pressure magnitudes. In spite of non-homogeneous distribution of atoms within the collagen molecule, the calculated values of local mechanical properties have been found to carry the same order of magnitude along the longitudinal and transverse directions. It has been demonstrated that the values of global mechanical properties like compressibility, bulk modulus, etc. as well as local mechanical properties like linear compressibility, linear elastic modulus, etc. are functions of magnitudes of applied hydrostatic pressures. The mechanical characteristics of collagen molecule based on the atomistic model have also been compared with that of the continuum model in the present work. The comparison showed up orthotropic material behavior for the collagen molecule. The information on collagen molecule provided in the present study can be very helpful in designing the future bio-materials.

  20. Mechanisms of lamellar collagen formation in connective tissues.

    Science.gov (United States)

    Ghazanfari, Samaneh; Khademhosseini, Ali; Smit, Theodoor H

    2016-08-01

    The objective of tissue engineering is to regenerate functional tissues. Engineering functional tissues requires an understanding of the mechanisms that guide the formation and evolution of structure in the extracellular matrix (ECM). In particular, the three-dimensional (3D) collagen fiber arrangement is important as it is the key structural determinant that provides mechanical integrity and biological function. In this review, we survey the current knowledge on collagen organization mechanisms that can be applied to create well-structured functional lamellar tissues and in particular intervertebral disc and cornea. Thus far, the mechanisms behind the formation of cross-aligned collagen fibers in the lamellar structures is not fully understood. We start with cell-induced collagen alignment and strain-stabilization behavior mechanisms which can explain a single anisotropically aligned collagen fiber layer. These mechanisms may explain why there is anisotropy in a single layer in the first place. However, they cannot explain why a consecutive collagen layer is laid down with an alternating alignment. Therefore, we explored another mechanism, called liquid crystal phasing. While dense concentrations of collagen show such behavior, there is little evidence that the conditions for liquid crystal phasing are actually met in vivo. Instead, lysyl aldehyde-derived collagen cross-links have been found essential for correct lamellar matrix deposition. Furthermore, we suggest that supra-cellular (tissue-level) shear stress may be instrumental in the alignment of collagen fibers. Understanding the potential mechanisms behind the lamellar collagen structure in connective tissues will lead to further improvement of the regeneration strategies of functional complex lamellar tissues. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Mechanical response of collagen molecule under hydrostatic compression.

    Science.gov (United States)

    Saini, Karanvir; Kumar, Navin

    2015-04-01

    Proteins like collagen are the basic building blocks of various body tissues (soft and hard). Collagen molecules find their presence in the skeletal system of the body where they bear mechanical loads from different directions, either individually or along with hydroxy-apatite crystals. Therefore, it is very important to understand the mechanical behavior of the collagen molecule which is subjected to multi-axial state of loading. The estimation of strains of collagen molecule along different directions resulting from the changes in hydrostatic pressure magnitude, can provide us new insights into its mechanical behavior. In the present work, full atomistic simulations have been used to study global (volumetric) as well as local (along different directions) mechanical properties of the hydrated collagen molecule which is subjected to different hydrostatic pressure magnitudes. To estimate the local mechanical properties, the strains of collagen molecule along its longitudinal and transverse directions have been acquired at different hydrostatic pressure magnitudes. In spite of non-homogeneous distribution of atoms within the collagen molecule, the calculated values of local mechanical properties have been found to carry the same order of magnitude along the longitudinal and transverse directions. It has been demonstrated that the values of global mechanical properties like compressibility, bulk modulus, etc. as well as local mechanical properties like linear compressibility, linear elastic modulus, etc. are functions of magnitudes of applied hydrostatic pressures. The mechanical characteristics of collagen molecule based on the atomistic model have also been compared with that of the continuum model in the present work. The comparison showed up orthotropic material behavior for the collagen molecule. The information on collagen molecule provided in the present study can be very helpful in designing the future bio-materials. Copyright © 2015 Elsevier B.V. All rights

  2. Mechanical response of collagen molecule under hydrostatic compression

    Energy Technology Data Exchange (ETDEWEB)

    Saini, Karanvir, E-mail: karans@iitrpr.ac.in; Kumar, Navin

    2015-04-01

    Proteins like collagen are the basic building blocks of various body tissues (soft and hard). Collagen molecules find their presence in the skeletal system of the body where they bear mechanical loads from different directions, either individually or along with hydroxy-apatite crystals. Therefore, it is very important to understand the mechanical behavior of the collagen molecule which is subjected to multi-axial state of loading. The estimation of strains of collagen molecule along different directions resulting from the changes in hydrostatic pressure magnitude, can provide us new insights into its mechanical behavior. In the present work, full atomistic simulations have been used to study global (volumetric) as well as local (along different directions) mechanical properties of the hydrated collagen molecule which is subjected to different hydrostatic pressure magnitudes. To estimate the local mechanical properties, the strains of collagen molecule along its longitudinal and transverse directions have been acquired at different hydrostatic pressure magnitudes. In spite of non-homogeneous distribution of atoms within the collagen molecule, the calculated values of local mechanical properties have been found to carry the same order of magnitude along the longitudinal and transverse directions. It has been demonstrated that the values of global mechanical properties like compressibility, bulk modulus, etc. as well as local mechanical properties like linear compressibility, linear elastic modulus, etc. are functions of magnitudes of applied hydrostatic pressures. The mechanical characteristics of collagen molecule based on the atomistic model have also been compared with that of the continuum model in the present work. The comparison showed up orthotropic material behavior for the collagen molecule. The information on collagen molecule provided in the present study can be very helpful in designing the future bio-materials.

  3. Uniform spatial distribution of collagen fibril radii within tendon implies local activation of pC-collagen at individual fibrils

    Science.gov (United States)

    Rutenberg, Andrew D.; Brown, Aidan I.; Kreplak, Laurent

    2016-08-01

    Collagen fibril cross-sectional radii show no systematic variation between the interior and the periphery of fibril bundles, indicating an effectively constant rate of collagen incorporation into fibrils throughout the bundle. Such spatially homogeneous incorporation constrains the extracellular diffusion of collagen precursors from sources at the bundle boundary to sinks at the growing fibrils. With a coarse-grained diffusion equation we determine stringent bounds, using parameters extracted from published experimental measurements of tendon development. From the lack of new fibril formation after birth, we further require that the concentration of diffusing precursors stays below the critical concentration for fibril nucleation. We find that the combination of the diffusive bound, which requires larger concentrations to ensure homogeneous fibril radii, and lack of nucleation, which requires lower concentrations, is only marginally consistent with fully processed collagen using conservative bounds. More realistic bounds may leave no consistent concentrations. Therefore, we propose that unprocessed pC-collagen diffuses from the bundle periphery followed by local C-proteinase activity and subsequent collagen incorporation at each fibril. We suggest that C-proteinase is localized within bundles, at fibril surfaces, during radial fibrillar growth. The much greater critical concentration of pC-collagen, as compared to fully processed collagen, then provides broad consistency between homogeneous fibril radii and the lack of fibril nucleation during fibril growth.

  4. Chemical structure of chromium(III) crosslinked collagen-poly(methyl methacrylate) copolymers in radiation grafting

    International Nuclear Information System (INIS)

    Pietrucha, K.

    1991-01-01

    Upon γ-irradiation of aqueous emulsions of methyl methacrylate embedded into chrome tanned skin, the formation of graft copolymers is observed. The number-average molecular weight of the grafted poly(methyl methacrylate) side chains was in the range of 430000 (for a dose of 10 kGy) and practically independent of grafting degree. However, the number of branches per graft copolymer molecule increases from 0.3 to 0.8 when the degree of grafting increases from 32% to 88%. Similarly, the radiation yield, i.e. the number of branches formed per 100 eV of energy absorbed in the substrate polymer increases from 0.75 to 1.94. The value and meaning of molecular weight of graft copolymer is discussed along with the mechanism of polymer chain termination. (author) 14 refs.; 3 figs.; 4 tabs

  5. Collagen Type III and VI Turnover in Response to Long-Term Immobilization

    DEFF Research Database (Denmark)

    Sun, Shu; Henriksen, Kim; Karsdal, Morten A

    2015-01-01

    with immobilization and/or remobilization. METHODS: In the Berlin bed rest study, 20 young men were recruited and randomly assigned to 8-week's strict bed rest with or without resistive vibration exercise countermeasure. We measured three neo-epitope ELISA kits in the serum samples of this study: Pro-C3, measured...... to unloading or reloading, whereas C6M does not appear to respond to unloading. Pro-C3 and C6M levels correlate with LBM at baseline, while Pro-C6 is related to the anabolic and catabolic responses to unloading and reloading....

  6. Goodpasture's autoimmune disease - A collagen IV disorder.

    Science.gov (United States)

    Pedchenko, Vadim; Richard Kitching, A; Hudson, Billy G

    2018-05-12

    Goodpasture's (GP) disease is an autoimmune disorder characterized by the deposition of pathogenic autoantibodies in basement membranes of kidney and lung eliciting rapidly progressive glomerulonephritis and pulmonary hemorrhage. The principal autoantigen is the α345 network of collagen IV, which expression is restricted to target tissues. Recent discoveries include a key role of chloride and bromide for network assembly, a novel posttranslational modification of the antigen, a sulfilimine bond that crosslinks the antigen, and the mechanistic role of HLA in genetic susceptibility and resistance to GP disease. These advances provide further insights into molecular mechanisms of initiation and progression of GP disease and serve as a basis for developing of novel diagnostic tools and therapies for treatment of Goodpasture's disease. Copyright © 2017. Published by Elsevier B.V.

  7. Subclinical pulmonary involvement in collagen vascular diseases

    International Nuclear Information System (INIS)

    Dansin, E.; Wallaert, B.; Jardin, M.R.; Remy, J.; Hatron, P.Y.; Tonnel, A.B.

    1990-01-01

    A recruitment of immune and inflammatory cells into alveolar spaces has been reported in patients with collagen vascular diseases (CVD) and a normal chest radiograph. These findings defined the concept of subclinical alveolitis (SCA). To determine whether SCA may be associated with CT signs of interstitial lung disease (ILD), the authors of this paper compared bronchoalveolar lavage (BAL) findings and high-resolution (HRCT) scans in 36 patients with CVD and normal chest radiographs (systemic sclerosis [SS, n = 21], rheumatoid arthritis [RA, n = 9], primary Sjogren's syndrome [PS, n = 6]). HRCT scans were obtained in supine and prone positions. Results of BAL revealed SCA in 17/36 patients (47%); lymphocyte SCA in 4/36 (24%); neutrophil SCA in 7/36 (41%); and mixed SCA in 6/36 (35%)

  8. Cutaneous collagenous vasculopathy: A rare case report

    Directory of Open Access Journals (Sweden)

    Kinjal Deepak Rambhia

    2016-01-01

    Full Text Available Cutaneous collagenous vasculopathy (CCV is a distinct, rare, and underdiagnosed condition. We report a case of CCV in a 50-year-old woman presenting as asymptomatic, erythematous to hyperpigmented nonblanchable macules over both the lower extremities. The clinical differential diagnosis of the lesions was pigmented purpuric dermatoses (Schamberg's purpura and cutaneous small vessel vasculitis. Histology of the lesions revealed dilated superficial dermal vessels with abundant pink hyaline material in the vessel wall, which stained with periodic acid Schiff stain. The patient was diagnosed as CCV. This condition remains largely underdiagnosed and is commonly mistaken for pigmented purpuric dermatosis or generalized essential telangiectasia. Emphasis on the differentiation of CCV from its clinical and histological mimicks is made.

  9. Corneal collagen crosslinking and pigment dispersion syndrome.

    Science.gov (United States)

    LaHood, Benjamin R; Moore, Sacha

    2017-03-01

    We describe the case of a keratoconus patient with pigment dispersion syndrome (PDS) who was treated for progressive corneal ectasia with corneal collagen crosslinking (CXL). Pigment dispersion syndrome has been shown to have associated morphologic changes of the corneal endothelium. Corneal CXL has the potential to cause toxicity to the corneal endothelium, and adjacent pigment might increase the likelihood of damage. In this case, the presence of PDS had no detrimental effect on the outcome of treatment, and no complications were observed at 12 months follow-up, indicating that it may be safe to perform corneal CXL in the setting of PDS. This is an important observation as the number of indications for corneal CXL grows. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  10. High-strength mineralized collagen artificial bone

    Science.gov (United States)

    Qiu, Zhi-Ye; Tao, Chun-Sheng; Cui, Helen; Wang, Chang-Ming; Cui, Fu-Zhai

    2014-03-01

    Mineralized collagen (MC) is a biomimetic material that mimics natural bone matrix in terms of both chemical composition and microstructure. The biomimetic MC possesses good biocompatibility and osteogenic activity, and is capable of guiding bone regeneration as being used for bone defect repair. However, mechanical strength of existing MC artificial bone is too low to provide effective support at human load-bearing sites, so it can only be used for the repair at non-load-bearing sites, such as bone defect filling, bone graft augmentation, and so on. In the present study, a high strength MC artificial bone material was developed by using collagen as the template for the biomimetic mineralization of the calcium phosphate, and then followed by a cold compression molding process with a certain pressure. The appearance and density of the dense MC were similar to those of natural cortical bone, and the phase composition was in conformity with that of animal's cortical bone demonstrated by XRD. Mechanical properties were tested and results showed that the compressive strength was comparable to human cortical bone, while the compressive modulus was as low as human cancellous bone. Such high strength was able to provide effective mechanical support for bone defect repair at human load-bearing sites, and the low compressive modulus can help avoid stress shielding in the application of bone regeneration. Both in vitro cell experiments and in vivo implantation assay demonstrated good biocompatibility of the material, and in vivo stability evaluation indicated that this high-strength MC artificial bone could provide long-term effective mechanical support at human load-bearing sites.

  11. Isolation and Characterization of Collagen and Antioxidant Collagen Peptides from Scales of Croceine Croaker (Pseudosciaena crocea

    Directory of Open Access Journals (Sweden)

    Bin Wang

    2013-11-01

    Full Text Available Acid soluble collagen (ASC from scales of croceine croaker (ASC-C was successfully isolated with the yield of 0.37% ± 0.08% (dry weight basis, and characterized as type I collagen on the basis of amino acid analysis and electrophoretic pattern. The antioxidant hydrolysate of ASC-C (ACH was prepared through a two-stage in vitro digestion (4-h trypsin followed by 4-h pepsin, and three antioxidant peptides (ACH-P1, ACH-P2, and ACH-P3 were further isolated from ACH using ultrafiltration, gel chromatography, and RP-HPLC, and their amino acid sequences were identified as GFRGTIGLVG (ACH-P1, GPAGPAG (ACH-P2, and GFPSG (ACH-P3. ACH-P1, ACH-P2, and ACH-P3 showed good scavenging activities on hydroxyl radical (IC50 0.293, 0.240, and 0.107 mg/mL, respectively, DPPH radical (IC50 1.271, 0.675, and 0.283 mg/mL, respectively, superoxide radical (IC50 0.463, 0.099, and 0.151 mg/mL, respectively, and ABTS radical (IC50 0.421, 0.309, and 0.210 mg/mL, respectively. ACH-P3 was also effectively against lipid peroxidation in the model system. The antioxidant activities of three collagen peptides were due to the presence of hydrophobic amino acid residues within the peptide sequences. The collagen peptides might be used as antioxidant for the therapy of diseases associated with oxidative stress, or reducing oxidative changes during storage.

  12. Characterization of electron beam irradiated collagen-polyvinylpyrrolidone (PVP) and collagen-dextran (DEX) blends

    International Nuclear Information System (INIS)

    Dumitrascu, M.; Sima, E.; Minea, R.; Vancea, C.; Meltze, V.; Albu, M.G.

    2011-01-01

    Complete text of publication follows. The aim of the present study was to investigate the influence of electron beam irradiation on some blends of collagen-polyvinylpyrrolidone (PVP) and collagen-dextran (DEX). The blends were prepared by mixing different quantities of collagen, PVP and DEX in distilled water. After irradiation the obtained hydrogels were processed by controlled drying and freeze-drying. Both types of materials were characterized by FT-IR, FT-Raman, TG, DSC, water uptake and SEM. The intensity of the characteristic bands, in the range 2800-3600 cm -1 from FT-IR spectra, varied considerably as function of absorbed radiation dose. Raman spectra revealed the absence of the characteristic peak at 2700 cm -1 for irradiated blends at 30 kGy. Kinetic parameters were calculated from the TG, DTG and DSC data by means of isoconversion methods at different heating rates. Thereby a relation between absorbed radiation dose and activation energy was established. Water uptake studies were carried out in PBS solution (phosphate buffer saline) at 37 deg C and pH = 7.4 and the results revealed a decrease of the water uptake with increasing of absorbed radiation dose.

  13. High levels of biomarkers of collagen remodeling are associated with increased mortality in COPD – results from the ECLIPSE study

    DEFF Research Database (Denmark)

    Sand, Jannie M B; Leeming, Diana J; Byrjalsen, Inger

    2016-01-01

    with mortality in COPD and measured neo-epitopes originating from ECM proteins associated with lung tissue remodeling. METHODS: Biomarkers of ECM remodeling were assessed in a subpopulation (n = 1000) of the Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-points (ECLIPSE) cohort. Validated......BACKGROUND: There is a need to identify individuals with COPD at risk for disease progression and mortality. Lung tissue remodeling is associated with the release of extracellular matrix (ECM) fragments into the peripheral circulation. We hypothesized that ECM remodeling was associated...... immunoassays measuring serological neo-epitopes produced by proteolytic cleavage associated with degradation of collagen type I, III, IV, and VI, elastin, and biglycan, and formation of collagen type VI as well as fibrinogen and C-reactive protein were used. Multivariate models were used to assess...

  14. Differentiation of human endometrial stem cells into urothelial cells on a three-dimensional nanofibrous silk-collagen scaffold: an autologous cell resource for reconstruction of the urinary bladder wall.

    Science.gov (United States)

    Shoae-Hassani, Alireza; Mortazavi-Tabatabaei, Seyed Abdolreza; Sharif, Shiva; Seifalian, Alexander Marcus; Azimi, Alireza; Samadikuchaksaraei, Ali; Verdi, Javad

    2015-11-01

    Reconstruction of the bladder wall via in vitro differentiated stem cells on an appropriate scaffold could be used in such conditions as cancer and neurogenic urinary bladder. This study aimed to examine the potential of human endometrial stem cells (EnSCs) to form urinary bladder epithelial cells (urothelium) on nanofibrous silk-collagen scaffolds, for construction of the urinary bladder wall. After passage 4, EnSCs were induced by keratinocyte growth factor (KGF) and epidermal growth factor (EGF) and seeded on electrospun collagen-V, silk and silk-collagen nanofibres. Later we tested urothelium-specific genes and proteins (uroplakin-Ia, uroplakin-Ib, uroplakin-II, uroplakin-III and cytokeratin 20) by immunocytochemistry, RT-PCR and western blot analyses. Scanning electron microscopy (SEM) and histology were used to detect cell-matrix interactions. DMEM/F12 supplemented by KGF and EGF induced EnSCs to express urothelial cell-specific genes and proteins. Either collagen, silk or silk-collagen scaffolds promoted cell proliferation. The nanofibrous silk-collagen scaffolds provided a three-dimensional (3D) structure to maximize cell-matrix penetration and increase differentiation of the EnSCs. Human EnSCs seeded on 3D nanofibrous silk-collagen scaffolds and differentiated to urothelial cells provide a suitable source for potential use in bladder wall reconstruction in women. Copyright © 2013 John Wiley & Sons, Ltd.

  15. Extraction and Characterization of Collagen from Sea Cucumber Flesh

    Directory of Open Access Journals (Sweden)

    Alhana

    2015-11-01

    Full Text Available Sea cucumber (Stichopus variegatus is one of the Echinodermata phylum that grows along Indonesian coastal. Sea cucumber is potential source of collagen. The purposes of this research were to determine the optimal concentration of NaOH and CH3COOH solution in collagen production and analyze the physicochemical characteristics of collagen from S. variegatus. Yield of the collagen was 1.5% (based on wet weight basis, produced by pretreatment with NaOH 0,30%, hydrolysis with CH3COOH 0.10% and extracted using distilled water. Protein, moisture, and ash content of the collagen was 67.68%, 13.64%, and 4.15%, respectively. Collagen was extracted using distilled water at 45°C during 2h and still had triple helix structure ; pH 7.37 ; melting temperature 163.67°C and whiteness 69.25%. The major amino acid content of collagen were glycine, alanine, proline and glutamic acid.

  16. Collagen-Gold Nanoparticle Conjugates for Versatile Biosensing

    Directory of Open Access Journals (Sweden)

    Sarah Unser

    2017-02-01

    Full Text Available Integration of noble metal nanoparticles with proteins offers promising potential to create a wide variety of biosensors that possess both improved selectivity and versatility. The multitude of functionalities that proteins offer coupled with the unique optical properties of noble metal nanoparticles can allow for the realization of simple, colorimetric sensors for a significantly larger range of targets. Herein, we integrate the structural protein collagen with 10 nm gold nanoparticles to develop a protein-nanoparticle conjugate which possess the functionality of the protein with the desired colorimetric properties of the nanoparticles. Applying the many interactions that collagen undergoes in the extracellular matrix, we are able to selectively detect both glucose and heparin with the same collagen-nanoparticle conjugate. Glucose is directly detected through the cross-linking of the collagen fibrils, which brings the attached nanoparticles into closer proximity, leading to a red-shift in the LSPR frequency. Conversely, heparin is detected through a competition assay in which heparin-gold nanoparticles are added to solution and compete with heparin in the solution for the binding sites on the collagen fibrils. The collagen-nanoparticle conjugates are shown to detect both glucose and heparin in the physiological range. Lastly, glucose is selectively detected in 50% mouse serum with the collagen-nanoparticle devices possessing a linear range of 3–25 mM, which is also within the physiologically relevant range.

  17. Fibrosis of extracellular matrix is related to the duration of the disease but is unrelated to the dynamics of collagen metabolism in dilated cardiomyopathy.

    Science.gov (United States)

    Rubiś, Paweł; Wiśniowska-Śmialek, Sylwia; Wypasek, Ewa; Biernacka-Fijalkowska, Barbara; Rudnicka-Sosin, Lucyna; Dziewiecka, Ewa; Faltyn, Patrycja; Khachatryan, Lusine; Karabinowska, Aleksandra; Kozanecki, Artur; Tomkiewicz-Pająk, Lidia; Podolec, Piotr

    2016-12-01

    Fibrosis of extracellular matrix (ECM) in dilated cardiomyopathy (DCM) corresponds to the myocardial over-production of various types of collagens. However, mechanism of this process is poorly understood. To investigate whether enhanced metabolism of ECM occur in DCM. Seventy consecutive DCM patients (pts) (48 ± 12.1 years, EF 24.4 ± 7.4 %) and 20 healthy volunteers were studied. Based on symptoms duration, pts were divided into new-onset (n = 35, 6 months) and chronic DCM (n = 35, >6 months). Markers of collagen type I and III synthesis-procollagen type I carboxy- and amino-terminal peptides (PICP and PINP) and procollagen type III carboxy- and amino-terminal peptides (PIIICP and PIIINP), collagen 1 (col-1), ECM metabolism controlling factors-tumor growth factor beta-1 (TGF1-β), connective tissue growth factor (CTGF), and ECM degradation enzymes-matrix metalloproteinases (MMP-2, MMP-9) and their tissue inhibitor (TIMP-1) were measured in serum. All pts underwent right ventricular endomyocardial biopsy to study ECM fibrosis. The presence of fibrosis was detected in 24 (34.3 %) pts and was more prevalent in chronic DCM [17 (48.6 %) vs. 7 (20 %), p collagen type III prevailed over collagen type I. ECM metabolism was not different in DCM regardless of the duration of the disease and status of myocardial fibrosis. Serum markers of ECM metabolism were found not to be useful for the prediction of myocardial fibrosis in DCM.

  18. Structural properties of pepsin-solubilized collagen acylated by lauroyl chloride along with succinic anhydride

    International Nuclear Information System (INIS)

    Li, Conghu; Tian, Zhenhua; Liu, Wentao; Li, Guoying

    2015-01-01

    The structural properties of pepsin-solubilized calf skin collagen acylated by lauroyl chloride along with succinic anhydride were investigated in this paper. Compared with native collagen, acylated collagen retained the unique triple helix conformation, as determined by amino acid analysis, circular dichroism and X-ray diffraction. Meanwhile, the thermostability of acylated collagen using thermogravimetric measurements was enhanced as the residual weight increased by 5%. With the temperature increased from 25 to 115 °C, the secondary structure of native and acylated collagens using Fourier transform infrared spectroscopy measurements was destroyed since the intensity of the major amide bands decreased and the positions of the major amide bands shifted to lower wavenumber, respectively. Meanwhile, two-dimensional correlation spectroscopy revealed that the most sensitive bands for acylated and native collagens were amide I and II bands, respectively. Additionally, the corresponding order of the groups between native and acylated collagens was different and the correlation degree for acylated collagen was weaker than that of native collagen, suggesting that temperature played a small influence on the conformation of acylated collagen, which might be concluded that the hydrophobic interaction improved the thermostability of collagen. - Highlights: • Acylated collagen retained the unique triple helix conformation. • Acylated collagen had stronger thermostability than native collagen. • Amide I was the most sensitive band to the temperature for acylated collagen. • Amide II was the most sensitive band to the temperature for native collagen. • Auto-peak at 1680 cm −1 for acylated collagen disappeared at higher temperature

  19. Double thermal transitions of type I collagen in acidic solution.

    Science.gov (United States)

    Liu, Yan; Liu, Lingrong; Chen, Mingmao; Zhang, Qiqing

    2013-01-01

    Contributed equally to this work. To further understand the origin of the double thermal transitions of collagen in acidic solution induced by heating, the denaturation of acidic soluble collagen was investigated by micro-differential scanning calorimeter (micro-DSC), circular dichroism (CD), dynamic laser light scattering (DLLS), transmission electron microscopy (TEM), and two-dimensional (2D) synchronous fluorescence spectrum. Micro-DSC experiments revealed that the collagen exhibited double thermal transitions, which were located within 31-37 °C (minor thermal transition, T(s) ∼ 33 °C) and 37-55 °C (major thermal transition, T(m) ∼ 40 °C), respectively. The CD spectra suggested that the thermal denaturation of collagen resulted in transition from polyproline II type structure to unordered structure. The DLLS results showed that there were mainly two kinds of collagen fibrillar aggregates with different sizes in acidic solution and the larger fibrillar aggregates (T(p2) = 40 °C) had better heat resistance than the smaller one (T(p1) = 33 °C). TEM revealed that the depolymerization of collagen fibrils occurred and the periodic cross-striations of collagen gradually disappeared with increasing temperature. The 2D fluorescence correlation spectra were also applied to investigate the thermal responses of tyrosine and phenylalanine residues at the molecular level. Finally, we could draw the conclusion that (1) the minor thermal transition was mainly due to the defibrillation of the smaller collagen fibrillar aggregates and the unfolding of a little part of triple helices; (2) the major thermal transition primarily arose from the defibrillation of the larger collagen fibrillar aggregates and the complete denaturation of the majority part of triple helices.

  20. Collagen-like proteins in pathogenic E. coli strains.

    Directory of Open Access Journals (Sweden)

    Neelanjana Ghosh

    Full Text Available The genome sequences of enterohaemorrhagic E. coli O157:H7 strains show multiple open-reading frames with collagen-like sequences that are absent from the common laboratory strain K-12. These putative collagens are included in prophages embedded in O157:H7 genomes. These prophages carry numerous genes related to strain virulence and have been shown to be inducible and capable of disseminating virulence factors by horizontal gene transfer. We have cloned two collagen-like proteins from E. coli O157:H7 into a laboratory strain and analysed the structure and conformation of the recombinant proteins and several of their constituting domains by a variety of spectroscopic, biophysical, and electron microscopy techniques. We show that these molecules exhibit many of the characteristics of vertebrate collagens, including trimer formation and the presence of a collagen triple helical domain. They also contain a C-terminal trimerization domain, and a trimeric α-helical coiled-coil domain with an unusual amino acid sequence almost completely lacking leucine, valine or isoleucine residues. Intriguingly, these molecules show high thermal stability, with the collagen domain being more stable than those of vertebrate fibrillar collagens, which are much longer and post-translationally modified. Under the electron microscope, collagen-like proteins from E. coli O157:H7 show a dumbbell shape, with two globular domains joined by a hinged stalk. This morphology is consistent with their likely role as trimeric phage side-tail proteins that participate in the attachment of phage particles to E. coli target cells, either directly or through assembly with other phage tail proteins. Thus, collagen-like proteins in enterohaemorrhagic E. coli genomes may have a direct role in the dissemination of virulence-related genes through infection of harmless strains by induced bacteriophages.

  1. Collagen: A review on its sources and potential cosmetic applications.

    Science.gov (United States)

    Avila Rodríguez, María Isabela; Rodríguez Barroso, Laura G; Sánchez, Mirna Lorena

    2018-02-01

    Collagen is a fibrillar protein that conforms the conjunctive and connective tissues in the human body, essentially skin, joints, and bones. This molecule is one of the most abundant in many of the living organisms due to its connective role in biological structures. Due to its abundance, strength and its directly proportional relation with skin aging, collagen has gained great interest in the cosmetic industry. It has been established that the collagen fibers are damaged with the pass of time, losing thickness and strength which has been strongly related with skin aging phenomena [Colágeno para todo. 60 y más. 2016. http://www.revista60ymas.es/InterPresent1/groups/revistas/documents/binario/ses330informe.pdf.]. As a solution, the cosmetic industry incorporated collagen as an ingredient of different treatments to enhance the user youth and well-being, and some common presentations are creams, nutritional supplement for bone and cartilage regeneration, vascular and cardiac reconstruction, skin replacement, and augmentation of soft skin among others [J App Pharm Sci. 2015;5:123-127]. Nowadays, the biomolecule can be obtained by extraction from natural sources such as plants and animals or by recombinant protein production systems including yeast, bacteria, mammalian cells, insects or plants, or artificial fibrils that mimic collagen characteristics like the artificial polymer commercially named as KOD. Because of its increased use, its market size is valued over USD 6.63 billion by 2025 [Collagen Market By Source (Bovine, Porcine, Poultry, Marine), Product (Gelatin, Hydrolyzed Collagen), Application (Food & Beverages, Healthcare, Cosmetics), By Region, And Segment Forecasts, 2014 - 2025. Grand View Research. http://www.grandviewresearch.com/industry-analysis/collagen-market. Published 2017.]. Nevertheless, there has been little effort on identifying which collagen types are the most suitable for cosmetic purposes, for which the present review will try to enlighten

  2. Triple helix-forming oligonucleotide corresponding to the polypyrimidine sequence in the rat alpha 1(I) collagen promoter specifically inhibits factor binding and transcription.

    Science.gov (United States)

    Kovacs, A; Kandala, J C; Weber, K T; Guntaka, R V

    1996-01-19

    Type I and III fibrillar collagens are the major structural proteins of the extracellular matrix found in various organs including the myocardium. Abnormal and progressive accumulation of fibrillar type I collagen in the interstitial spaces compromises organ function and therefore, the study of transcriptional regulation of this gene and specific targeting of its expression is of major interest. Transient transfection of adult cardiac fibroblasts indicate that the polypurine-polypyrimidine sequence of alpha 1(I) collagen promoter between nucleotides - 200 and -140 represents an overall positive regulatory element. DNase I footprinting and electrophoretic mobility shift assays suggest that multiple factors bind to different elements of this promoter region. We further demonstrate that the unique polypyrimidine sequence between -172 and -138 of the promoter represents a suitable target for a single-stranded polypurine oligonucleotide (TFO) to form a triple helix DNA structure. Modified electrophoretic mobility shift assays show that this TFO specifically inhibits the protein-DNA interaction within the target region. In vitro transcription assays and transient transfection experiments demonstrate that the transcriptional activity of the promoter is inhibited by this oligonucleotide. We propose that TFOs represent a therapeutic potential to specifically influence the expression of alpha 1(I) collagen gene in various disease states where abnormal type I collagen accumulation is known to occur.

  3. Analysis of transcriptional isoforms of collagen types IX, II, and I in the developing avian cornea by competitive polymerase chain reaction.

    Science.gov (United States)

    Fitch, J M; Gordon, M K; Gibney, E P; Linsenmayer, T F

    1995-01-01

    The genes for the alpha 1(IX), alpha 1(II), and alpha 2(I) collagen chains can give rise to different isoforms of mRNA, generated by alternative promotor usage [for alpha 1(IX) and alpha 2(I)] or alternative splicing [for alpha 1(II)]. In this study, we employed competitive reverse transcriptase PCR to quantitate the amounts of transcriptional isoforms for these genes in the embryonic avian cornea from its inception (about 3 1/2 days of development) to 11 days. In order to compare values at different time points, the results were normalized to those obtained for the "housekeeping" enzyme, glycerol-3-phosphate dehydrogenase (G3PDH). These values were compared to those obtained from other tissues (anterior optic cup and cartilage) that synthesize different combinations of the collagen isoforms. We found that, in the cornea, transcripts from the upstream promotor of alpha 1(IX) collagen (termed "long IX") were predominant at stage 18-20 (about 3 1/2 days), but then fell rapidly, and remained at a low level. By 5 days (just before stromal swelling) the major mRNA isoform of alpha 1(IX) was from the downstream promoter (termed "short IX"). The relative amount of transcript for the short form of type IX collagen rose to a peak at about 6 days of development, and then declined. Throughout this period, the predominant transcriptional isoform of the collagen type II gene was IIA (i.e., containing the alternatively spliced exon 2). This indicates that the molecules of type II collagen that are assembled into heterotypic fibrils with type I collagen possess, at least transiently, an amino-terminal globular domain similar to that found in collagen types I, III, and V. For type I, the "bone/tendon" mRNA isoform of the alpha 2(I) collagen gene was predominant; transcripts from the downstream promotor were at basal levels. In other tissues expressing collagen types IX and II, long IX was expressed predominantly with the IIA form in the anterior optic cup at stage 22/23; in 14 1

  4. The adsorption of 117Snm(IV)-EDTMP on collagen

    International Nuclear Information System (INIS)

    Yang Yuqing; Luo Shunzhong; Pu Manfei; Bing Wenzeng; He Jiaheng; Wang Guanquan

    2002-01-01

    The adsorption and desorption characteristics of 117 Sn m (IV)-EDTMP on collage are studied, and compared with that on HA. The results show that the effects of pH and temperature on adsorption of 117 Sn m (IV)-EDTMP on collagen are similar to those on HA, and that the adsorption equilibrium and adsorption model of 117 Sn m (IV)-EDTMP on collagen are completely different from those on HA; 117 Sm m -EDTMP absorbed on collagen are extremely stable and almost could not be desorbed with normal saline or EDTMP

  5. Isolation and Characterization of Collagen from Chicken Feet

    OpenAIRE

    P. Hashim; M. S. Mohd Ridzwan; J. Bakar

    2014-01-01

    Collagen was isolated from chicken feet by using papain and pepsin enzymes in acetic acid solution at 4°C for 24h with a yield of 18.16% and 22.94% by dry weight, respectively. Chemical composition and characteristics of chicken feet collagen such as amino acid composition, SDS-PAGE patterns, FTIR spectra and thermal properties were evaluated. The chicken feet collagen is rich in the amino acids glycine, glutamic acid, proline and hydroxyproline. Electrophoresis pattern demonstrated two disti...

  6. Automated image analysis in the study of collagenous colitis

    DEFF Research Database (Denmark)

    Fiehn, Anne-Marie Kanstrup; Kristensson, Martin; Engel, Ulla

    2016-01-01

    PURPOSE: The aim of this study was to develop an automated image analysis software to measure the thickness of the subepithelial collagenous band in colon biopsies with collagenous colitis (CC) and incomplete CC (CCi). The software measures the thickness of the collagenous band on microscopic...... slides stained with Van Gieson (VG). PATIENTS AND METHODS: A training set consisting of ten biopsies diagnosed as CC, CCi, and normal colon mucosa was used to develop the automated image analysis (VG app) to match the assessment by a pathologist. The study set consisted of biopsies from 75 patients...

  7. Peripheral hepatic arterial embolization with cross-linked collagen fibers

    International Nuclear Information System (INIS)

    Daniels, J.R.; Kerlan, R.K. Jr.; Dodds, L.; McLaughlin, P.; La Berge, J.M.; Harrington, D.; Daniels, A.M.; Ring, E.J.

    1986-01-01

    Hepatic artery embolization with a nonimmunogenic, cross-linked collagen preparation (Angiostat, collagen for embolization, Target Therapeutics) was studied in mongrel dogs. Flow-directed technique was used to achieve complete distal arterial occlusion. Serial liver function evaluation demonstrated marked alterations at 48 to 72 hours, partial correction at 1 week, and resolution of abnormalities by 1 month. Restoration of large-vessel blood flow was angiographically demonstrable at 1 week. Recanalization, achieved by migration of endothelial cells around the collagen, resulted in complete restoration of normal hepatic vascular and tissue anatomy at 1 month. Repeated embolization at biweekly intervals was well tolerated

  8. Metallothionein (MT)-III

    DEFF Research Database (Denmark)

    Carrasco, J; Giralt, M; Molinero, A

    1999-01-01

    Metallothionein-III is a low molecular weight, heavy-metal binding protein expressed mainly in the central nervous system. First identified as a growth inhibitory factor (GIF) of rat cortical neurons in vitro, it has subsequently been shown to be a member of the metallothionein (MT) gene family...... injected rats. The specificity of the antibody was also demonstrated in immunocytochemical studies by the elimination of the immunostaining by preincubation of the antibody with brain (but not liver) extracts, and by the results obtained in MT-III null mice. The antibody was used to characterize...... the putative differences between the rat brain MT isoforms, namely MT-I+II and MT-III, in the freeze lesion model of brain damage, and for developing an ELISA for MT-III suitable for brain samples. In the normal rat brain, MT-III was mostly present primarily in astrocytes. However, lectin staining indicated...

  9. Structure of collagen-glycosaminoglycan matrix and the influence to its integrity and stability.

    Science.gov (United States)

    Bi, Yuying; Patra, Prabir; Faezipour, Miad

    2014-01-01

    Glycosaminoglycan (GAG) is a chain-like disaccharide that is linked to polypeptide core to connect two collagen fibrils/fibers and provide the intermolecular force in Collagen-GAG matrix (C-G matrix). Thus, the distribution of GAG in C-G matrix contributes to the integrity and mechanical properties of the matrix and related tissue. This paper analyzes the transverse isotropic distribution of GAG in C-G matrix. The angle of GAGs related to collagen fibrils is used as parameters to qualify the GAGs isotropic characteristic in both 3D and 2D rendering. Statistical results included that over one third of GAGs were perpendicular directed to collagen fibril with symmetrical distribution for both 3D matrix and 2D plane cross through collagen fibrils. The three factors tested in this paper: collagen radius, collagen distribution, and GAGs density, were not statistically significant for the strength of Collagen-GAG matrix in 3D rendering. However in 2D rendering, a significant factor found was the radius of collagen in matrix for the GAGs directed to orthogonal plane of Collagen-GAG matrix. Between two cross-section selected from Collagen-GAG matrix model, the plane cross through collagen fibrils was symmetrically distributed but the total percentage of perpendicular directed GAG was deducted by decreasing collagen radius. There were some symmetry features of GAGs angle distribution in selected 2D plane that passed through space between collagen fibrils, but most models showed multiple peaks in GAGs angle distribution. With less GAGs directed to perpendicular of collagen fibril, strength in collagen cross-section weakened. Collagen distribution was also a factor that influences GAGs angle distribution in 2D rendering. True hexagonal collagen packaging is reported in this paper to have less strength at collagen cross-section compared to quasi-hexagonal collagen arrangement. In this work focus is on GAGs matrix within the collagen and its relevance to anisotropy.

  10. Osteogenesis imperfecta type III/Ehlers-Danlos overlap syndrome in a Chinese man.

    Science.gov (United States)

    Lu, Yanqin; Wang, Yanzhou; Rauch, Frank; Li, Hu; Zhang, Yao; Zhai, Naixiang; Zhang, Jian; Ren, Xiuzhi; Han, Jinxiang

    2018-02-01

    Osteogenesis imperfecta (OI) and Ehlers-Danlos syndrome (EDS) are rare genetic disorders that are typically inherited in an autosomal dominant manner. Few cases of OI/EDS overlap syndrome have been documented. Described here is a 30-year-old Chinese male with OI type III and EDS. Sequencing of genomic DNA revealed a heterozygous COL1A1 mutation (c.671G>A, p.Gly224Asp) that affected the N-anchor domain of the alpha 1 chain of collagen type I. Ultrastructural analysis of a skin biopsy specimen revealed thin collagen fibers with irregular alignment of collagen fibers. These findings have expanded the genotypic spectrum of the OI/EDS overlap syndrome.

  11. Collagen degradation in the abdominal aneurysm: A conspiracy of matrix metalloproteinase and cysteine collagenases

    NARCIS (Netherlands)

    Abdul-Hussien, H.; Soekhoe, R.G.V.; Weber, E.; Thüsen, J.H. von der; Kleemann, R.; Mulder, A.; Hajo Van Bockel, J.; Hanemaaijer, R.; Lindeman, J.H.N.

    2007-01-01

    Growth and rupture of abdominal aortic aneurysms (AAAs) result from increased collagen turnover. Collagen turnover critically depends on specific collagenases that cleave the triple helical region of fibrillar collagen. As yet, the collagenases responsible for collagen degradation in AAAs have not

  12. Fibronectin- and collagen-mimetic ligands regulate bone marrow stromal cell chondrogenesis in three-dimensional hydrogels

    Directory of Open Access Journals (Sweden)

    JT Connelly

    2011-09-01

    Full Text Available Modification of tissue engineering scaffolds with bioactive molecules is a potential strategy for modulating cell behavior and guiding tissue regeneration. While adhesion to RGD peptides has been shown to inhibit in vitro chondrogenesis, the effects of extracellular matrix (ECM-mimetic ligands with complex secondary and tertiary structures are unknown. This study aimed to determine whether collagen- and fibronectin-mimetic ligands would retain biologic functionality in three-dimensional (3D hydrogels, whether different ECM-mimetic ligands differentially influence in vitro chondrogenesis, and if effects of ligands on differentiation depend on soluble biochemical stimuli. A linear RGD peptide, a recombinant fibronectin fragment containing the seven to ten Type III repeats (FnIII7-10 and a triple helical, collagen mimetic peptide with the GFOGER motif were covalently coupled to agarose gels using the sulfo-SANPAH crosslinker, and bone marrow stromal cells (BMSCs were cultured within the 3D hydrogels. The ligands retained biologic functionality within the agarose gels and promoted density-dependent BMSC spreading. Interactions with all adhesive ligands inhibited stimulation by chondrogenic factors of collagen Type II and aggrecan mRNA levels and deposition of sulfated glycosaminoglycans. In medium containing fetal bovine serum, interactions with the GFOGER peptide enhanced mRNA expression of the osteogenic gene osteocalcin whereas FnIII7-10 inhibited osteocalcin expression. In conclusion, modification of agarose hydrogels with ECM-mimetic ligands can influence the differentiation of BMSCs in a manner that depends strongly on the presence and nature of soluble biochemical stimuli.

  13. Comparison of the properties of collagen extracted from dried ...

    African Journals Online (AJOL)

    sunny t

    2016-04-20

    Apr 20, 2016 ... proteins have been studied and a comparison made of the protein patterns of collagen extracted ... indicating some differences in amino acid sequence or conformation. ... encephalopathy (TSE) and foot and mouth disease.

  14. COLLAGENOUS SPHERULES OF THE BREAST: A DIAGNOSTIC ENIGMA

    Directory of Open Access Journals (Sweden)

    Amrit Kaur

    2016-05-01

    Full Text Available INTRODUCTION Collagenous spherule (CS is an enigmatic finding in a breast lesion involving the lobular acini and ductules and is defined with the presence of eosinophilic intraluminal collagen rich spherules measuring 20-100 microns in diameter, surrounded by flattened myoepithelial cells. 1 It is an uncommon incidental finding in less than 1-2% of biopsies associated with various benign and malignant diseases occurring in isolation or multifocally. 2 A major growing concern surrounding collagenous spherules is that it might be misinterpreted as atypical ductal hyperplasia (ADH, cribriform ductal carcinoma in situ (DCIS, cribriform carcinoma or adenoid cystic carcinoma of breast. We present a case of mobile cystic mass of the breast reported as fibrocystic disease of the breast with focal areas showing adenosis and hyperplastic changes with multiple ducts displayed a peculiar change with the presence of extracellular concentric hyaline material present within the intraluminal space, diagnostic of collagenous spherules.

  15. Matrix remodeling between cells and cellular interactions with collagen bundle

    Science.gov (United States)

    Kim, Jihan; Sun, Bo

    When cells are surrounded by complex environment, they continuously probe and interact with it by applying cellular traction forces. As cells apply traction forces, they can sense rigidity of their local environment and remodel the matrix microstructure simultaneously. Previous study shows that single human carcinoma cell (MDA-MB-231) remodeled its surrounding extracellular matrix (ECM) and the matrix remodeling was reversible. In this study we examined the matrix microstructure between cells and cellular interaction between them using quantitative confocal microscopy. The result shows that the matrix microstructure is the most significantly remodeled between cells consisting of aligned, and densified collagen fibers (collagen bundle)., the result shows that collagen bundle is irreversible and significantly change micromechanics of ECM around the bundle. We further examined cellular interaction with collagen bundle by analyzing dynamics of actin and talin formation along with the direction of bundle. Lastly, we analyzed dynamics of cellular protrusion and migrating direction of cells along the bundle.

  16. Collagen mRNA levels changes during colorectal cancer carcinogenesis

    DEFF Research Database (Denmark)

    Skovbjerg, Hanne; Anthonsen, Dorit; Lothe, Inger M B

    2009-01-01

    BACKGROUND: Invasive growth of epithelial cancers is a complex multi-step process which involves dissolution of the basement membrane. Type IV collagen is a major component in most basement membranes. Type VII collagen is related to anchoring fibrils and is found primarily in the basement membrane...... zone of stratified epithelia. Immunohistochemical studies have previously reported changes in steady-state levels of different alpha(IV) chains in several epithelial cancer types. In the present study we aimed to quantitatively determine the mRNA levels of type IV collagen (alpha1/alpha 4/alpha 6......) and type VII collagen (alpha1) during colorectal cancer carcinogenesis. METHODS: Using quantitative RT-PCR, we have determined the mRNA levels for alpha1(IV), alpha 4(IV), alpha 6(IV), and alpha1(VII) in colorectal cancer tissue (n = 33), adenomas (n = 29) and in normal tissue from the same individuals...

  17. Osmotic pressure induced tensile forces in tendon collagen.

    Science.gov (United States)

    Masic, Admir; Bertinetti, Luca; Schuetz, Roman; Chang, Shu-Wei; Metzger, Till Hartmut; Buehler, Markus J; Fratzl, Peter

    2015-01-22

    Water is an important component of collagen in tendons, but its role for the function of this load-carrying protein structure is poorly understood. Here we use a combination of multi-scale experimentation and computation to show that water is an integral part of the collagen molecule, which changes conformation upon water removal. The consequence is a shortening of the molecule that translates into tensile stresses in the range of several to almost 100 MPa, largely surpassing those of about 0.3 MPa generated by contractile muscles. Although a complete drying of collagen would be relevant for technical applications, such as the fabrication of leather or parchment, stresses comparable to muscle contraction already occur at small osmotic pressures common in biological environments. We suggest, therefore, that water-generated tensile stresses may play a role in living collagen-based materials such as tendon or bone.

  18. Biocompatibility and tissue regenerating capacity of crosslinked dermal sheep collagen

    NARCIS (Netherlands)

    van Wachem, P.B.; van Luyn, M.J.A.; Olde Damink, L.H.H.; Olde damink, L.H.H.; Dijkstra, Pieter J.; Feijen, Jan; Nieuwenhuis, P.

    1994-01-01

    The biocompatibility and tissue regenerating capacity of four crosslinked dermal sheep collagens (DSC) was studied. In vitro, the four DSC versions were found to be noncytotoxic or very low in cytoxicity. After subcutaneous implantation in rats, hexamethylenediisocyanatecrcrosslinked DSC (HDSC)

  19. Enhanced physicochemical properties of collagen by using EDC ...

    Indian Academy of Sciences (India)

    MS received 4 July 2011; revised 21 December 2011. Abstract. Collagen-based .... On the other hand, in the process of crosslinking, carboxyl and amino groups that .... logy Plan Project of Fujian Department of Education, China. (Grant no.

  20. Collagenous and other organizations in mature annelid cuticle and epidermis.

    Science.gov (United States)

    Humphreys, S; Porter, K R

    1976-05-01

    The mature annelid cuticle contains orthogonally oriented collagen in a matrix capped superficially by a dense epicuticle with external corpuscles. The underlying epidermis is a simple columnar epithelium with two major cell types, mucous-secreting cells which secrete through channels in the cuticle to the exterior of the worm, and "supportive" cells which presumably produce and increase the cuticle by secreting into it. The structures of supportive cells, previously interpreted as specialized for establishing interfibrillar collagen order, are revealed by glutaraldehyde fixation as common cellular components without the qualities deemed useful to align collagen. Cell processes which penetrate and sometimes pass completely through the cuticle are not stable, not in geometric order, and lack cilia-like structure. Cilia, unlike the ubiquitous cellular processes, are highly restricted to regions of the epidermis with specialized functions. Cellular control, or other control, of collagen fibrillogenesis remains unestablished.

  1. Applying Knowledge on Collagen of CLRI: In Human Health Care

    Indian Academy of Sciences (India)

    Applying Knowledge on Collagen of CLRI: In Human Health Care ... Kollagen & NeuSkin are products in the market based on technologies. ... derived products of biomedical value in tissue remodeling and engineering are in advanced stage ...

  2. Biosynthesis of collagen by fibroblasts kept in culture

    International Nuclear Information System (INIS)

    Machado-Santelli, G.M.

    1978-01-01

    The sinthesis of collagen is studied in fibroblasts of different origins with the purpose of obtaining an appropriate system for the study of its biosynthesis and processing. The percentage of collagen synthesis vary according to the fibroblast origin. Experiences are performed with fibroblasts kept in culture from: chicken - and guinea pig embryos, carragheenin - induced granulomas in adult guinea pig and from human skin. The collagen pattern synthesized after acetic acid - or saline extractions in the presence of inhibitors is also determined. This pattern is then assayed by poliacrilamide - 5% - SDS gel electrophoresis accompanied by fluorography. The importance of the cell culture system in the elucidation of collagen biosynthesis is pointed out. (M.A.) [pt

  3. Collagen cross-linking in thin corneas

    Directory of Open Access Journals (Sweden)

    Prema Padmanabhan

    2013-01-01

    Full Text Available Collagen cross-linking (CXL has become the standard of care for progressive keratoconus, after numerous clinical studies have established its efficacy and safety in suitably selected eyes. The standard protocol is applicable in eyes which have a minimum corneal thickness of 400 μm after epithelial debridement. This prerequisite was stipulated to protect the corneal endothelium and intraocular tissues from the deleterious effect of ultraviolet-A (UVA radiation. However, patients with keratoconus often present with corneal thickness of less than 400 μm and could have otherwise benefited from this procedure. A few modifications of the standard procedure have been suggested to benefit these patients without a compromise in safety. Transepithelial cross-linking, pachymetry-guided epithelial debridement before cross-linking, and the use of hypoosmolar riboflavin are some of the techniques that have been attempted. Although clinical data is limited at the present time, these techniques are worth considering in patients with thin corneas. Further studies are needed to scientifically establish their efficacy and safety.

  4. Newly identified interfibrillar collagen crosslinking suppresses cell proliferation and remodelling.

    Science.gov (United States)

    Marelli, Benedetto; Le Nihouannen, Damien; Hacking, S Adam; Tran, Simon; Li, Jingjing; Murshed, Monzur; Doillon, Charles J; Ghezzi, Chiara E; Zhang, Yu Ling; Nazhat, Showan N; Barralet, Jake E

    2015-06-01

    Copper is becoming recognised as a key cation in a variety of biological processes. Copper chelation has been studied as a potential anti-angiogenic strategy for arresting tumour growth. Conversely the delivery of copper ions and complexes in vivo can elicit a pro-angiogenic effect. Previously we unexpectedly found that copper-stimulated intraperitoneal angiogenesis was accompanied by collagen deposition. Here, in hard tissue, not only was healing accelerated by copper, but again enhanced deposition of collagen was detected at 2 weeks. Experiments with reconstituted collagen showed that addition of copper ions post-fibrillogenesis rendered plastically-compressed gels resistant to collagenases, enhanced their mechanical properties and increased the denaturation temperature of the protein. Unexpectedly, this apparently interfibrillar crosslinking was not affected by addition of glucose or ascorbic acid, which are required for crosslinking by advanced glycation end products (AGEs). Fibroblasts cultured on copper-crosslinked gels did not proliferate, whereas those cultured with an equivalent quantity of copper on either tissue culture plastic or collagen showed no effect compared with controls. Although non-proliferative, fibroblasts grown on copper-cross-linked collagen could migrate, remained metabolically active for at least 14 days and displayed a 6-fold increase in Mmps 1 and 3 mRNA expression compared with copper-free controls. The ability of copper ions to crosslink collagen fibrils during densification and independently of AGEs or Fenton type reactions is previously unreported. The effect on MMP susceptibility of collagen and the dramatic change in cell behaviour on this crosslinked ECM may contribute to shedding some light on unexplained phenomena as the apparent benefit of copper complexation in fibrotic disorders or the enhanced collagen deposition in response to localised copper delivery. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Dynamic interplay between the collagen scaffold and tumor evolution

    DEFF Research Database (Denmark)

    Egeblad, Mikala; Rasch, Morten G; Weaver, Valerie M

    2010-01-01

    and remodeling of the ECM network regulate tissue tension, generate pathways for migration, and release ECM protein fragments to direct normal developmental processes such as branching morphogenesis. Collagens are major components of the ECM of which basement membrane type IV and interstitial matrix type I...... are the most prevalent. Here we discuss how abnormal expression, proteolysis and structure of these collagens influence cellular functions to elicit multiple effects on tumors, including proliferation, initiation, invasion, metastasis, and therapy response....

  6. Enhancing amine terminals in an amine-deprived collagen matrix.

    LENUS (Irish Health Repository)

    Tiong, William H C

    2008-10-21

    Collagen, though widely used as a core biomaterial in many clinical applications, is often limited by its rapid degradability which prevents full exploitation of its potential in vivo. Polyamidoamine (PAMAM) dendrimer, a highly branched macromolecule, possesses versatile multiterminal amine surface groups that enable them to be tethered to collagen molecules and enhance their potential. In this study, we hypothesized that incorporation of PAMAM dendrimer in a collagen matrix through cross-linking will result in a durable, cross-linked collagen biomaterial with free -NH 2 groups available for further multi-biomolecular tethering. The aim of this study was to assess the physicochemical properties of a G1 PAMAM cross-linked collagen matrix and its cellular sustainability in vitro. Different amounts of G1 PAMAM dendrimer (5 or 10 mg) were integrated into bovine-derived collagen matrices through a cross-linking process, mediated by 5 or 25 mM 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) in 5 mM N-hydroxysuccinimide (NHS) and 50 mM 2-morpholinoethane sulfonic acid buffer at pH 5.5. The physicochemical properties of resultant matrices were investigated with scanning electron microscopy (SEM), collagenase degradation assay, differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectra, and ninhydrin assay. Cellular sustainability of the matrices was assessed with Alamar Blue assay and SEM. There was no significant difference in cellular behavior between the treated and nontreated groups. However, the benefit of incorporating PAMAM in the cross-linking reaction was limited when higher concentrations of either agent were used. These results confirm the hypothesis that PAMAM dendrimer can be incorporated in the collagen cross-linking process in order to modulate the properties of the resulting cross-linked collagen biomaterial with free -NH 2 groups available for multi-biomolecular tethering.

  7. Collagen metabolism and basement membrane formation in cultures of mouse mammary epithelial cells: Induction of assembly on fibrillar type I collagen substrata

    International Nuclear Information System (INIS)

    David, G.; van der Schueren, B.; van den Berghe, H.; Nusgens, B.; Van Cauwenberge, D.; Lapiere, C.

    1987-01-01

    Collagen metabolism was compared in cultures of mouse mammary epithelial cells maintained on plastic or fibrillar type I collagen gel substrata. The accumulation of dialysable and non-dialysable [ 3 H]hydroxyproline and the identification of the collagens produced suggest no difference between substrata in the allover rates of collagen synthesis and degradation. The proportion of the [ 3 H]collagen which accumulates in the monolayers of cultures on collagen, however, markedly exceeds that of cultures on plastic. Cultures on collagen deposit a sheet-like layer of extracellular matrix materials on the surface of the collagen fibers. Transformed cells on collagen produce and accumulate more [ 3 H]collage, yet are less effective in basement membrane formation than normal cells, indicting that the accumulation of collagen alone and the effect of interstitial collagen thereupon do not suffice. Thus, exogenous fibrillar collagen appears to enhance, but is not sufficient for proper assembly of collagenous basement membrane components near the basal epithelial cell surface

  8. A 3D Electroactive Polypyrrole-Collagen Fibrous Scaffold for Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Kam W. Leong

    2011-02-01

    Full Text Available Fibers that can provide topographical, biochemical and electrical cues would be attractive for directing the differentiation of stem cells into electro-responsive cells such as neuronal or muscular cells. Here we report on the fabrication of polypyrrole-incorporated collagen-based fibers via interfacial polyelectrolyte complexation (IPC. The mean ultimate tensile strength of the fibers is 304.0 ± 61.0 MPa and the Young’s Modulus is 10.4 ± 4.3 GPa. Human bone marrow-derived mesenchymal stem cells (hMSCs are cultured on the fibers in a proliferating medium and stimulated with an external electrical pulse generator for 5 and 10 days. The effects of polypyrrole in the fiber system can be observed, with hMSCs adopting a neuronal-like morphology at day 10, and through the upregulation of neural markers, such as noggin, MAP2, neurofilament, β tubulin III and nestin. This study demonstrates the potential of this fiber system as an attractive 3D scaffold for tissue engineering, where collagen is present on the fiber surface for cellular adhesion, and polypyrrole is encapsulated within the fiber for enhanced electrical communication in cell-substrate and cell-cell interactions.

  9. The insulin-like growth factor axis and collagen turnover during prednisolone treatment

    DEFF Research Database (Denmark)

    Wolthers, O D; Juul, A; Hansen, M

    1994-01-01

    Serum concentrations of insulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein 3 (IGFBP-3), the carboxyterminal propeptide of type I collagen (PICP), the carboxyterminal pyridinoline crosslinked telopeptide of type I collagen (ICTP), and the aminoterminal propeptide...... of type III procollagen (PIIINP) were studied in 10 prepubertal children with asthma (mean age 9.0 years). The children were treated with 2.5 and 5.0 mg/day prednisolone in a randomised double blind crossover trial with run in, treatment, and washout periods of two weeks. No statistically significant...... effects on serum concentrations of IGF-I and IGFBP-3 were found. Dose related reductions of PICP, ICTP, and PIIINP were observed: the mean (SEM) reduction in PICP was 33.4 (26.3) and 68.4 (20.6) micrograms/l, in ICTP 2.5 (0.5) and 2.9 (0.6) micrograms/l, and in PIIINP 2.1 (0.7) and 3.1 (1.8) micrograms...

  10. Oxidative damage to collagen and related substrates by metal ion/hydrogen peroxide systems

    DEFF Research Database (Denmark)

    Hawkins, C L; Davies, Michael Jonathan

    1997-01-01

    . In this study electron paramagnetic resonance spectroscopy with spin trapping has been used to identify radicals formed on collagen and related materials by metal ion-H2O2 mixtures. Attack of the hydroxyl radical, from a Fe(II)-H2O2 redox couple, on collagen peptides gave signals from both side chain (.CHR...... are similar to those from the alpha-carbon site of peptides and the side-chain of lysine. Enzymatic digestion of the large, protein-derived, species releases similar low-molecular-weight adducts. The metal ion employed has a dramatic effect on the species observed. With Cu(I)-H2O2 or Cu(II)-H2O2 instead of Fe(II)-H......2O2, evidence has been obtained for: i) altered sites of attack and fragmentation, ii) C-terminal decarboxylation, and iii) hydrogen abstraction at N-terminal alpha-carbon sites. This altered behaviour is believed to be due to the binding of copper ions to some substrates and hence site...

  11. The insulin-like growth factor axis and collagen turnover in asthmatic children treated with inhaled budesonide

    DEFF Research Database (Denmark)

    Wolthers, O D; Juul, A; Hansen, M

    1995-01-01

    Serum concentrations of growth hormone-dependent insulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3), the carboxy terminal propeptide of type I procollagen (PICP), the carboxy terminal pyridinoline cross-linked telopeptide of type I collagen (ICTP......) and the amino terminal propeptide of type III procollagen (PIIINP) were studied in 14 prepubertal children with asthma (mean age 9.7 years) during treatment with inhaled budesonide. The study design was a randomized, crossover trial with two double-blind treatment periods (200 and 800 micrograms) and one open...

  12. Changes in type I collagen following laser welding.

    Science.gov (United States)

    Bass, L S; Moazami, N; Pocsidio, J; Oz, M C; LoGerfo, P; Treat, M R

    1992-01-01

    Selection of ideal laser parameters for tissue welding is inhibited by poor understanding of the mechanism. We investigated structural changes in collagen molecules extracted from rat tail tendon (> 90% type I collagen) after tissue welding using an 808 nm diode laser and indocyanine green dye applied to the weld site. Mobility patterns on SDS-PAGE were identical in the lasered and untreated tendon extracts with urea or acetic acid. Pepsin incubation after acetic acid extraction revealed a reduction of collagen alpha and beta bands in lasered compared with untreated specimens. Circular dichroism studies of rat tail tendon showed absence of helical structure in collagen from lasered tendon. No evidence for covalent bonding was present in laser-treated tissues. Collagen molecules are denatured by the laser wavelength and parameters used in this study. No significant amount of helical structure is regenerated on cooling. We conclude that non-covalent interactions between denatured collagen molecules may be responsible for the creation of tissue welding.

  13. A three-dimensional computational model of collagen network mechanics.

    Directory of Open Access Journals (Sweden)

    Byoungkoo Lee

    Full Text Available Extracellular matrix (ECM strongly influences cellular behaviors, including cell proliferation, adhesion, and particularly migration. In cancer, the rigidity of the stromal collagen environment is thought to control tumor aggressiveness, and collagen alignment has been linked to tumor cell invasion. While the mechanical properties of collagen at both the single fiber scale and the bulk gel scale are quite well studied, how the fiber network responds to local stress or deformation, both structurally and mechanically, is poorly understood. This intermediate scale knowledge is important to understanding cell-ECM interactions and is the focus of this study. We have developed a three-dimensional elastic collagen fiber network model (bead-and-spring model and studied fiber network behaviors for various biophysical conditions: collagen density, crosslinker strength, crosslinker density, and fiber orientation (random vs. prealigned. We found the best-fit crosslinker parameter values using shear simulation tests in a small strain region. Using this calibrated collagen model, we simulated both shear and tensile tests in a large linear strain region for different network geometry conditions. The results suggest that network geometry is a key determinant of the mechanical properties of the fiber network. We further demonstrated how the fiber network structure and mechanics evolves with a local formation, mimicking the effect of pulling by a pseudopod during cell migration. Our computational fiber network model is a step toward a full biomechanical model of cellular behaviors in various ECM conditions.

  14. Effects of isopropanol on collagen fibrils in new parchment

    Directory of Open Access Journals (Sweden)

    Gonzalez Lee G

    2012-03-01

    Full Text Available Abstract Background Isopropanol is widely used by conservators to relax the creases and folds of parchment artefacts. At present, little is known of the possible side effects of the chemical on parchments main structural component- collagen. This study uses X-ray Diffraction to investigate the effects of a range of isopropanol concentrations on the dimensions of the nanostructure of the collagen component of new parchment. Results It is found in this study that the packing features of the collagen molecules within the collagen fibril are altered by exposure to isopropanol. The results suggest that this chemical treatment can induce a loss of structural water from the collagen within parchment and thus a rearrangement of intermolecular bonding. This study also finds that the effects of isopropanol treatment are permanent to parchment artefacts and cannot be reversed with rehydration using deionised water. Conclusions This study has shown that isopropanol induces permanent changes to the packing features of collagen within parchment artefacts and has provided scientific evidence that its use to remove creases and folds on parchment artefacts will cause structural change that may contribute to long-term deterioration of parchment artefacts. This work provides valuable information that informs conservation practitioners regarding the use of isopropanol on parchment artefacts.

  15. Collagen-binding proteins of Streptococcus mutans and related streptococci.

    Science.gov (United States)

    Avilés-Reyes, A; Miller, J H; Lemos, J A; Abranches, J

    2017-04-01

    The ability of Streptococcus mutans to interact with collagen through the expression of collagen-binding proteins (CBPs) bestows this oral pathogen with an alternative to the sucrose-dependent mechanism of colonization classically attributed to caries development. Based on the abundance and distribution of collagen throughout the human body, stringent adherence to this molecule grants S. mutans with the opportunity to establish infection at different host sites. Surface proteins, such as SpaP, WapA, Cnm and Cbm, have been shown to bind collagen in vitro, and it has been suggested that these molecules play a role in colonization of oral and extra-oral tissues. However, robust collagen binding is not achieved by all strains of S. mutans, particularly those that lack Cnm or Cbm. These observations merit careful dissection of the contribution from these different CBPs towards tissue colonization and virulence. In this review, we will discuss the current understanding of mechanisms used by S. mutans and related streptococci to colonize collagenous tissues, and the possible contribution of CBPs to infections in different sites of the host. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. The Collagen Binding Proteins of Streptococcus mutans and Related Streptococci

    Science.gov (United States)

    Avilés-Reyes, Alejandro; Miller, James H.; Lemos, José A.; Abranches, Jacqueline

    2016-01-01

    Summary The ability of Streptococcus mutans to interact with collagen through the expression of collagen-binding proteins (CBPs) bestows this oral pathogen with an alternative to the sucrose-dependent mechanism of colonization classically attributed to caries development. Based on the abundance and distribution of collagen throughout the human body, stringent adherence to this molecule grants S. mutans with the opportunity to establish infection at different host sites. Surface proteins, such as SpaP, WapA, Cnm and Cbm, have been shown to bind collagen in vitro, and it has been suggested that these molecules play a role in colonization of oral and extra-oral tissues. However, robust collagen binding is not achieved by all strains of S. mutans, particularly those that lack Cnm or Cbm. These observations merit careful dissection of the contribution from these different CBPs towards tissue colonization and virulence. In this review, we will discuss the current understanding of mechanisms utilized by S. mutans and related streptococci to colonize collagenous tissues, and the possible contribution of CBPs to infections in different sites of the host. PMID:26991416

  17. Effects of tissue fixation and dehydration on tendon collagen nanostructure.

    Science.gov (United States)

    Turunen, Mikael J; Khayyeri, Hanifeh; Guizar-Sicairos, Manuel; Isaksson, Hanna

    2017-09-01

    Collagen is the most prominent protein in biological tissues. Tissue fixation is often required for preservation or sectioning of the tissue. This may affect collagen nanostructure and potentially provide incorrect information when analyzed after fixation. We aimed to unravel the effect of 1) ethanol and formalin fixation and 2) 24h air-dehydration on the organization and structure of collagen fibers at the nano-scale using small and wide angle X-ray scattering. Samples were divided into 4 groups: ethanol fixed, formalin fixed, and two untreated sample groups. Samples were allowed to air-dehydrate in handmade Kapton pockets during the measurements (24h) except for one untreated group. Ethanol fixation affected the collagen organization and nanostructure substantially and during 24h of dehydration dramatic changes were evident. Formalin fixation had minor effects on the collagen organization but after 12h of air-dehydration the spatial variation increased substantially, not evident in the untreated samples. Generally, collagen shrinkage and loss of alignment was evident in all samples during 24h of dehydration but the changes were subtle in all groups except the ethanol fixed samples. This study shows that tissue fixation needs to be chosen carefully in order to preserve the features of interest in the tissue. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Relative orientation of collagen molecules within a fibril: a homology model for homo sapiens type I collagen.

    Science.gov (United States)

    Collier, Thomas A; Nash, Anthony; Birch, Helen L; de Leeuw, Nora H

    2018-02-15

    Type I collagen is an essential extracellular protein that plays an important structural role in tissues that require high tensile strength. However, owing to the molecule's size, to date no experimental structural data are available for the Homo sapiens species. Therefore, there is a real need to develop a reliable homology model and a method to study the packing of the collagen molecules within the fibril. Through the use of the homology model and implementation of a novel simulation technique, we have ascertained the orientations of the collagen molecules within a fibril, which is currently below the resolution limit of experimental techniques. The longitudinal orientation of collagen molecules within a fibril has a significant effect on the mechanical and biological properties of the fibril, owing to the different amino acid side chains available at the interface between the molecules.

  19. NNDSS - Table III. Tuberculosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table III. Tuberculosis - 2018.This Table includes total number of cases reported in the United States, by region and by states, in accordance with the...

  20. NNDSS - Table III. Tuberculosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table III. Tuberculosis - 2017.This Table includes total number of cases reported in the United States, by region and by states, in accordance with the...

  1. Workshop 96. Part III

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    Part III of the proceedings contain 155 contributions in various fields of science and technology including nuclear engineering, environmental science, and biomedical engineering. Out of these, 10 were selected to be inputted in INIS. (P.A.).

  2. Workshop 96. Part III

    International Nuclear Information System (INIS)

    1995-12-01

    Part III of the proceedings contain 155 contributions in various fields of science and technology including nuclear engineering, environmental science, and biomedical engineering. Out of these, 10 were selected to be inputted in INIS. (P.A.)

  3. Stimulation of type I collagen activity in healing of pulp perforation

    OpenAIRE

    Kunarti, Sri

    2008-01-01

    Background: TGF-β1 is a connective tissue stimulant, potential regulator for tissue repair, and promoter in wound healing. The healing of pulp perforation is decided by quantity and quality of new collagen deposition. TGF-β1 upregulates collagen transcription. However, after several weeks production of type I collagen synthesis is stopped and enzymatic degradation of collagen matrix will occur. Purpose: Observe synthesis type I collagen during the process of pulp perforation healing in 7, 14,...

  4. Polarized Raman anisotropic response of collagen in tendon: towards 3D orientation mapping of collagen in tissues.

    Directory of Open Access Journals (Sweden)

    Leonardo Galvis

    Full Text Available In this study, polarized Raman spectroscopy (PRS was used to characterize the anisotropic response of the amide I band of collagen as a basis for evaluating three-dimensional collagen fibril orientation in tissues. Firstly, the response was investigated theoretically by applying classical Raman theory to collagen-like peptide crystal structures. The theoretical methodology was then tested experimentally, by measuring amide I intensity anisotropy in rat tail as a function of the orientation of the incident laser polarization. For the theoretical study, several collagen-like triple-helical peptide crystal structures obtained from the Protein Data Bank were rotated "in plane" and "out of plane" to evaluate the role of molecular orientation on the intensity of the amide I band. Collagen-like peptides exhibit a sinusoidal anisotropic response when rotated "in plane" with respect to the polarized incident laser. Maximal intensity was obtained when the polarization of the incident light is perpendicular to the molecule and minimal when parallel. In the case of "out of plane" rotation of the molecular structure a decreased anisotropic response was observed, becoming completely isotropic when the structure was perpendicular to the plane of observation. The theoretical Raman response of collagen was compared to that of alpha helical protein fragments. In contrast to collagen, alpha helices have a maximal signal when incident light is parallel to the molecule and minimal when perpendicular. For out-of-plane molecular orientations alpha-helix structures display a decreased average intensity. Results obtained from experiments on rat tail tendon are in excellent agreement with the theoretical predictions, thus demonstrating the high potential of PRS for experimental evaluation of the three-dimensional orientation of collagen fibers in biological tissues.

  5. Epicutaneous Immunization with Type II Collagen Inhibits both Onset and Progression of Chronic Collagen-Induced Arthritis

    OpenAIRE

    Strid, Jessica; Tan, Lee Aun; Strobel, Stephan; Londei, Marco; Callard, Robin

    2007-01-01

    Epicutaneous immunization is a potential non-invasive technique for antigen-specific immune-modulation. Topical application of protein antigens to barrier-disrupted skin induces potent antigen-specific immunity with a strong Th2-bias. In this study, we investigate whether the autoimmune inflammatory response of chronic collagen-induced arthritis (CCIA) in DBA/1-TCR-beta Tg mice can be modified by epicutaneous immunization. We show that epicutaneous immunization with type II collagen (CII) inh...

  6. Noninvasive Quantitative Imaging of Collagen Microstructure in Three-Dimensional Hydrogels Using High-Frequency Ultrasound.

    Science.gov (United States)

    Mercado, Karla P; Helguera, María; Hocking, Denise C; Dalecki, Diane

    2015-07-01

    Collagen I is widely used as a natural component of biomaterials for both tissue engineering and regenerative medicine applications. The physical and biological properties of fibrillar collagens are strongly tied to variations in collagen fiber microstructure. The goal of this study was to develop the use of high-frequency quantitative ultrasound to assess collagen microstructure within three-dimensional (3D) hydrogels noninvasively and nondestructively. The integrated backscatter coefficient (IBC) was employed as a quantitative ultrasound parameter to detect, image, and quantify spatial variations in collagen fiber density and diameter. Collagen fiber microstructure was varied by fabricating hydrogels with different collagen concentrations or polymerization temperatures. IBC values were computed from measurements of the backscattered radio-frequency ultrasound signals collected using a single-element transducer (38-MHz center frequency, 13-47 MHz bandwidth). The IBC increased linearly with increasing collagen concentration and decreasing polymerization temperature. Parametric 3D images of the IBC were generated to visualize and quantify regional variations in collagen microstructure throughout the volume of hydrogels fabricated in standard tissue culture plates. IBC parametric images of corresponding cell-embedded collagen gels showed cell accumulation within regions having elevated collagen IBC values. The capability of this ultrasound technique to noninvasively detect and quantify spatial differences in collagen microstructure offers a valuable tool to monitor the structural properties of collagen scaffolds during fabrication, to detect functional differences in collagen microstructure, and to guide fundamental research on the interactions of cells and collagen matrices.

  7. Hydroxyapatite/collagen bone-like nanocomposite.

    Science.gov (United States)

    Kikuchi, Masanori

    2013-01-01

    Our group has succeeded to synthesize material with bone-like nanostructure and bone-like inorganic and organic composition via self-organization mechanism between them using simultaneous titration method under controlled pH and temperature. The hydroxyapatite/collagen (HAp/Col) bone-like nanocomposite completely incorporated into bone remodeling process to be substituted by new bone. Cells cultured on the HAp/Col revealed very interesting reactions. Osteoblast-like MG63 cells showed upregulation of alkaline phosphatase >3 times greater than MG63 cells cultured on tissue culture polystyrene (TCPS). MG63 cells 3-dimensionally cultured in a "HAp/Col sponge," a porous HAp/Col having sponge-like viscoelasticity, accumulated calcium phosphate nodules on extracellular matrices they secreted. Bone marrow cells co-cultured with osteoblasts on HAp/Col differentiated to osteoclasts without differentiation supplements. This phenomenon is not found in cells cultured on hydroxyapatite ceramics and TCPS, and rarely in cells cultured on dentin. These results suggest that HAp/Col is a good candidate for tissue engineering of bone as well as bone filler. In a clinical test as a bone filler, the HAp/Col sponge was significantly better than porous β-tricalcium phosphate. The HAp/Col sponge has been approved by the Japanese government and will be used as greatly needed bone filler in patients. In addition to the above, HAp/Col coating on titanium revealed higher osteo-conductivity than HAp-coated titanium and bare titanium and improved direct bonding between titanium and newly formed bone. The HAp/Col coating may be used for metal devices requiring osseointegration.

  8. Ecological niche of Neanderthals from Spy Cave revealed by nitrogen isotopes of individual amino acids in collagen.

    Science.gov (United States)

    Naito, Yuichi I; Chikaraishi, Yoshito; Drucker, Dorothée G; Ohkouchi, Naohiko; Semal, Patrick; Wißing, Christoph; Bocherens, Hervé

    2016-04-01

    This study provides a refined view on the diet and ecological niche of Neanderthals. The traditional view is that Neanderthals obtained most of their dietary protein from terrestrial animals, especially from large herbivores that roamed the open landscapes. Evidence based on the conventional carbon and nitrogen isotopic composition of bulk collagen has supported this view, although recent findings based on plant remains in the tooth calculus, microwear analyses, and small game and marine animal remains from archaeological sites have raised some questions regarding this assumption. However, the lack of a protein source other than meat in the Neanderthal diet may be due to methodological difficulties in defining the isotopic composition of plants. Based on the nitrogen isotopic composition of glutamic acid and phenylalanine in collagen for Neanderthals from Spy Cave (Belgium), we show that i) there was an inter-individual dietary heterogeneity even within one archaeological site that has not been evident in bulk collagen isotopic compositions, ii) they occupied an ecological niche different from those of hyenas, and iii) they could rely on plants for up to ∼20% of their protein source. These results are consistent with the evidence found of plant consumption by the Spy Neanderthals, suggesting a broader subsistence strategy than previously considered. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Elevated expression of NEU1 sialidase in idiopathic pulmonary fibrosis provokes pulmonary collagen deposition, lymphocytosis, and fibrosis.

    Science.gov (United States)

    Luzina, Irina G; Lockatell, Virginia; Hyun, Sang W; Kopach, Pavel; Kang, Phillip H; Noor, Zahid; Liu, Anguo; Lillehoj, Erik P; Lee, Chunsik; Miranda-Ribera, Alba; Todd, Nevins W; Goldblum, Simeon E; Atamas, Sergei P

    2016-05-15

    Idiopathic pulmonary fibrosis (IPF) poses challenges to understanding its underlying cellular and molecular mechanisms and the development of better therapies. Previous studies suggest a pathophysiological role for neuraminidase 1 (NEU1), an enzyme that removes terminal sialic acid from glycoproteins. We observed increased NEU1 expression in epithelial and endothelial cells, as well as fibroblasts, in the lungs of patients with IPF compared with healthy control lungs. Recombinant adenovirus-mediated gene delivery of NEU1 to cultured primary human cells elicited profound changes in cellular phenotypes. Small airway epithelial cell migration was impaired in wounding assays, whereas, in pulmonary microvascular endothelial cells, NEU1 overexpression strongly impacted global gene expression, increased T cell adhesion to endothelial monolayers, and disrupted endothelial capillary-like tube formation. NEU1 overexpression in fibroblasts provoked increased levels of collagen types I and III, substantial changes in global gene expression, and accelerated degradation of matrix metalloproteinase-14. Intratracheal instillation of NEU1 encoding, but not control adenovirus, induced lymphocyte accumulation in bronchoalveolar lavage samples and lung tissues and elevations of pulmonary transforming growth factor-β and collagen. The lymphocytes were predominantly T cells, with CD8(+) cells exceeding CD4(+) cells by nearly twofold. These combined data indicate that elevated NEU1 expression alters functional activities of distinct lung cell types in vitro and recapitulates lymphocytic infiltration and collagen accumulation in vivo, consistent with mechanisms implicated in lung fibrosis.

  10. Collagen like peptide bioconjugates for targeted drug delivery applications

    Science.gov (United States)

    Luo, Tianzhi

    Collagen is the most abundant protein in mammals, and there has been long-standing interest in understanding and controlling collagen assembly in the design of new materials. Collagen-like peptides (CLP), also known as collagen-mimetic peptides (CMP), are short synthetic peptides which mimic the triple helical conformation of native collagens. In the past few decades, collagen like peptides and their conjugated hybrids have become a new class of biomaterials that possesses unique structures and properties. In addition to traditional applications of using CLPs to decipher the role of different amino acid residues and tripeptide motifs in stabilizing the collagen triple helix and mimicking collagen fibril formation, with the introduction of specific interactions including electrostatic interactions, pi-pi stacking interaction and metal-ligand coordination, a variety of artificial collagen-like peptides with well-defined sequences have been designed to create higher order assemblies with specific biological functions. The CLPs have also been widely used as bioactive domains or physical cross-linkers to fabricate hydrogels, which have shown potential to improve cell adhesion, proliferation and ECM macromolecule production. Despite this widespread use, the utilization of CLPs as domains in stimuli responsive bioconjugates represents a relatively new area for the development of functional polymeric materials. In this work, a new class of thermoresponsive diblock conjugates, containing collagen-like peptides and a thermoresponsive polymer, namely poly(diethylene glycol methyl ether methacrylate) (PDEGMEMA), is introduced. The CLP domain maintains its triple helix conformation after conjugation with the polymer. The engineered LCST of these conjugates has enabled temperature-induced assembly under aqueous conditions, at physiologically relevant temperatures, into well-defined vesicles with diameters of approximately 50-200 nm. The formation of nanostructures was driven by

  11. Heat Shock Protein 90 Inhibitor Decreases Collagen Synthesis of Keloid Fibroblasts and Attenuates the Extracellular Matrix on the Keloid Spheroid Model.

    Science.gov (United States)

    Lee, Won Jai; Lee, Ju Hee; Ahn, Hyo Min; Song, Seung Yong; Kim, Yong Oock; Lew, Dae Hyun; Yun, Chae-Ok

    2015-09-01

    The 90-kDa heat-shock protein (heat-shock protein 90) is an abundant cytosolic chaperone, and inhibition of heat-shock protein 90 by 17-allylamino-17-demethoxygeldanamycin (17-AAG) compromises transforming growth factor (TGF)-β-mediated transcriptional responses by enhancing TGF-β receptor I and II degradation, thus preventing Smad2/3 activation. In this study, the authors evaluated whether heat-shock protein 90 regulates TGF-β signaling in the pathogenesis and treatment of keloids. Keloid fibroblasts were treated with 17-AAG (10 μM), and mRNA levels of collagen types I and III were determined by real-time reverse- transcriptase polymerase chain reaction. Also, secreted TGF-β1 was assessed by enzyme-linked immunosorbent assay. The effect of 17-AAG on protein levels of Smad2/3 complex was determined by Western blot analysis. In addition, in 17-AAG-treated keloid spheroids, the collagen deposition and expression of major extracellular matrix proteins were investigated by means of Masson trichrome staining and immunohistochemistry. The authors found that heat-shock protein 90 is overexpressed in human keloid tissue compared with adjacent normal tissue, and 17-AAG decreased mRNA levels of type I collagen, secreted TGF-ß1, and Smad2/3 complex protein expression in keloid fibroblasts. Masson trichrome staining revealed that collagen deposition was decreased in 17-AAG-treated keloid spheroids, and immunohistochemical analysis showed that expression of collagen types I and III, elastin, and fibronectin was markedly decreased in 17-AAG-treated keloid spheroids. These results suggest that the antifibrotic action of heat-shock protein 90 inhibitors such as 17-AAG may have therapeutic effects on keloids.

  12. Collagenous sprue: a clinicopathologic study of 12 cases.

    LENUS (Irish Health Repository)

    Maguire, Aoife A

    2012-02-01

    Collagenous sprue is a rare form of small bowel enteropathy characterized by chronic diarrhea and progressive malabsorption with little data available on its natural history. The pathologic lesion consists of subepithelial collagen deposition associated with variable alterations in villous architecture. The small bowel biopsies of 12 cases were reviewed. Clinical details, celiac serology, and T-cell receptor gene rearrangement study results, when available, were collated. There were 8 females and 4 males (age ranged from 41 to 84 y) who presented with chronic diarrhea and weight loss. Small intestinal biopsies showed subepithelial collagen deposition with varying degrees of villous atrophy and varying numbers of intraepithelial lymphocytes. Four patients had previous biopsies showing enteropathic changes without collagen deposition. Seven cases were associated with collagenous colitis and 1 also had features of lymphocytic colitis. Three patients also had collagen deposition in gastric biopsies. One case was associated with lymphocytic gastritis. Celiac disease (CD, gluten-sensitive enteropathy) was documented in 4 patients. Five patients made a clinical improvement with combinations of a gluten-free diet and immunosuppressive therapy. Two patients died of complications of malnutrition and 1 of another illness. Clonal T-cell populations were identified in 5 of 6 cases tested. Four of these patients improved clinically after treatment but 1 has died. Collagenous sprue evolved on a background of CD in 4 cases. There was no history of CD in others and these cases may be the result of a biologic insult other than gluten sensitivity. None has developed clinical evidence of lymphoma to date.

  13. Resliced image space construction for coronary artery collagen fibers.

    Science.gov (United States)

    Luo, Tong; Chen, Huan; Kassab, Ghassan S

    2017-01-01

    Collagen fibers play an important role in the biomechanics of the blood vessel wall. The objective of this study was to determine the 3D microstructure of collagen fibers in the media and adventitia of coronary arteries. We present a novel optimal angle consistence algorithm to reform image slices in the visualization and analysis of 3D collagen images. 3D geometry was reconstructed from resliced image space where the 3D skeleton was extracted as the primary feature for accurate reconstruction of geometrical parameters. Collagen fibers (range 80-200) were reconstructed from the porcine coronary artery wall for the measurement of various morphological parameters. Collagen waviness and diameters were 1.37 ± 0.19 and 2.61 ± 0.89 μm, respectively. The biaxial distributions of orientation had two different peaks at 110.7 ± 25.2° and 18.4 ± 19.3°. Results for width, waviness, and orientation were found to be in good agreement with manual measurements. In addition to accurately measuring 2D features more efficiently than the manual approach, the present method produced 3D features that could not be measured in the 2D manual approach. These additional parameters included the tilt angle (5.10 ± 2.95°) and cross-sectional area (CSA; 5.98 ± 3.79 μm2) of collagen fibers. These 3D collagen reconstructions provide accurate and reliable microstructure for biomechanical modeling of vessel wall mechanics.

  14. Variation in the helical structure of native collagen.

    Directory of Open Access Journals (Sweden)

    Joseph P R O Orgel

    Full Text Available The structure of collagen has been a matter of curiosity, investigation, and debate for the better part of a century. There has been a particularly productive period recently, during which much progress has been made in better describing all aspects of collagen structure. However, there remain some questions regarding its helical symmetry and its persistence within the triple-helix. Previous considerations of this symmetry have sometimes confused the picture by not fully recognizing that collagen structure is a highly complex and large hierarchical entity, and this affects and is effected by the super-coiled molecules that make it. Nevertheless, the symmetry question is not trite, but of some significance as it relates to extracellular matrix organization and cellular integration. The correlation between helical structure in the context of the molecular packing arrangement determines which parts of the amino acid sequence of the collagen fibril are buried or accessible to the extracellular matrix or the cell. In this study, we concentrate primarily on the triple-helical structure of fibrillar collagens I and II, the two most predominant types. By comparing X-ray diffraction data collected from type I and type II containing tissues, we point to evidence for a range of triple-helical symmetries being extant in the molecules native environment. The possible significance of helical instability, local helix dissociation and molecular packing of the triple-helices is discussed in the context of collagen's supramolecular organization, all of which must affect the symmetry of the collagen triple-helix.

  15. The aminoterminal propeptide of type III procollagen. Studies on physiology and pathophysiology

    DEFF Research Database (Denmark)

    Jensen, L T

    1997-01-01

    receiving growth hormone therapy. We conclude: 1) That, for our purpose, the best method of determining PIIINP is the PIIINP RIA, owing to the profile of the substances determined. It was possible to improve the quality of the tracer and to increase sensitivity by changing the assay procedure. 2...... of peaks B and C (intact PIIINP) may, owing to the disposal rate, reflect changes in type III collagen turnover over one day (6 half-lives). The liver and kidneys actively take part in the degradation of circulating PIIINP. Serum concentrations of PIIINP in the presence of changing body composition (weight...... disappears when the body is in a catabolic state. Anabolic states give rise to increased serum concentrations of PIIINP as compared with normals states. The general conclusion is that serum PIIINP is a marker of type III collagen turnover under well-defined conditions. Serum PIIINP, mainly consisting...

  16. Periurethral injection of collagen in the treatment of urinary stress incontinence: ultrasonographic appearance

    Energy Technology Data Exchange (ETDEWEB)

    Leonhardt, C.; Krysl, J.; Arenson, A.M.; Herschorn, S. [Toronto Univ., ON (Canada). Faculty of Medicine

    1995-06-01

    Transvesical and transvaginal ultrasonography (US) was performed 26 times in 23 patients, 3 to 36 months after periurethral injection of collagen to treat symptomatic urinary stress incontinence. The appearance, location and volume of the collagen were recorded. In all the patients the injected collagen had the appearance of a well-circumscribed mass of variable size, located at the bladder base. Transvesical US demonstrated the collagen in only 17 of the patients, and allowed only limited visualization of the collagen in five of these 17 patients. However, transvaginal US demonstrated the collagen in all of them. The collagen collections showed various levels of echogenicity with both techniques. However, in patients with more than one deposit of collagen, the collections had similar echogenicity. The study indicated that US provides a rapid, noninvasive method of assessing collagen after periurethral injection, and that transvaginal US was the best method of visualizing such collections. 10 refs., 5 figs.

  17. [Three-dimensional parallel collagen scaffold promotes tendon extracellular matrix formation].

    Science.gov (United States)

    Zheng, Zefeng; Shen, Weiliang; Le, Huihui; Dai, Xuesong; Ouyang, Hongwei; Chen, Weishan

    2016-03-01

    To investigate the effects of three-dimensional parallel collagen scaffold on the cell shape, arrangement and extracellular matrix formation of tendon stem cells. Parallel collagen scaffold was fabricated by unidirectional freezing technique, while random collagen scaffold was fabricated by freeze-drying technique. The effects of two scaffolds on cell shape and extracellular matrix formation were investigated in vitro by seeding tendon stem/progenitor cells and in vivo by ectopic implantation. Parallel and random collagen scaffolds were produced successfully. Parallel collagen scaffold was more akin to tendon than random collagen scaffold. Tendon stem/progenitor cells were spindle-shaped and unified orientated in parallel collagen scaffold, while cells on random collagen scaffold had disorder orientation. Two weeks after ectopic implantation, cells had nearly the same orientation with the collagen substance. In parallel collagen scaffold, cells had parallel arrangement, and more spindly cells were observed. By contrast, cells in random collagen scaffold were disorder. Parallel collagen scaffold can induce cells to be in spindly and parallel arrangement, and promote parallel extracellular matrix formation; while random collagen scaffold can induce cells in random arrangement. The results indicate that parallel collagen scaffold is an ideal structure to promote tendon repairing.

  18. Non-Fourier thermal transport induced structural hierarchy and damage to collagen ultrastructure subjected to laser irradiation.

    Science.gov (United States)

    Sahoo, Nilamani; Narasimhan, Arunn; Dhar, Purbarun; Das, Sarit K

    2018-05-01

    Comprehending the mechanism of thermal transport through biological tissues is an important factor for optimal ablation of cancerous tissues and minimising collateral tissue damage. The present study reports detailed mapping of the rise in internal temperature within the tissue mimics due to NIR (1064 nm) laser irradiation, both for bare mimics and with gold nanostructures infused. Gold nanostructures such as mesoflowers and nanospheres have been synthesised and used as photothermal converters to enhance the temperature rise, resulting in achieving the desired degradation of malignant tissue in targeted region. Thermal history was observed experimentally and simulated considering non-Fourier dual phase lag (DPL) model incorporated Pennes bio-heat transfer equation using COMSOL Multiphysics software. The gross deviation in temperature i.e. rise from the classical Fourier model for bio-heat conduction suggests additional effects of temperature rise on the secondary structures and morphological and physico-chemical changes to the collagen ultrastructures building the tissue mass. The observed thermal denaturation in the collagen fibril morphologies have been explained based on the physico-chemical structure of collagen and its response to thermal radiation. The large shift in frequency of amides A and B is pronounced at a depth of maximum temperature rise compared with other positions in tissue phantom. Observations for change in band of amide I, amide II, and amide III are found to be responsible for damage to collagen ultra-structure. Variation in the concentration of gold nanostructures shows the potentiality of localised hyperthermia treatment subjected to NIR radiation through a proposed free radical mechanism.

  19. Differences in cytocompatibility between collagen, gelatin and keratin

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yanfang; Zhang, Weiwei; Yuan, Jiang, E-mail: jyuan@njnu.edu.cn; Shen, Jian, E-mail: jshen@njnu.edu.cn

    2016-02-01

    Keratins are cysteine-rich intermediate filament proteins found in the cytoskeleton of the epithelial cells and in the matrix of hair, feathers, wool, nails and horns. The natural abundance of cell adhesion sequences, RGD (Arg-Gly-Asp) and LDV (Leu-Asp-Val), makes them suitable for tissue engineering applications. The purpose of our study is to evaluate their cytocompatibility as compared to well-known collagen and gelatin proteins. Herein, collagen, gelatin and keratin were blended with poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and electrospun to afford nanofibrous mats, respectively. These PHBV/protein composite mats were characterized by field emission scanning electron microscopy (FE-SEM), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and dynamic mechanical analysis (DMA). The cytocompatibility was evaluated with cell adhesion, cell viability and cell proliferation. The data from MTT and BrDU revealed that collagen had significantly superior cytocompatibility as compared to gelatin and keratin. Gelatin showed a better cytocompatibility than keratin without statistical significance difference. Finally, we gave the reasons to account for the above conclusions. - Highlights: • Collagen, gelatin and keratin were coelectrospun with PHBV to afford nanofibrous mats. • Cytocompatibility was evaluated with cell adhesion, cell viability and cell proliferation. • Collagen had significantly superior cytocompatibility as compared to gelatin and keratin.

  20. Physicochemical properties of marine collagen-alginate biomaterial

    Science.gov (United States)

    Soon, K. S.; Hii, S. L.; Wong, C. L.; Leong, L. K.; Woo, K. K.

    2017-12-01

    Collagen base biomaterials are widely applied in the field of tissue engineering. However, these fibrous proteins in animal connective tissues are insufficient to fulfill the mechanical properties for such applications. Therefore, alginate as a natural polysaccharide was incorporated. In this study, Smooth wolf herring skins was collected from the local fish ball processing industry for collagen extraction using acid solubilisation method. On the other hand, alginate from brown seaweed (Sargassum polycystum) was extracted with calcium carbonate at 50 °C. The composite films of different collagen and alginate ratio were prepared by lyophilisation with pure collagen film as control. The effects of alginate on swelling behaviour, porosity, collagenase degradation and tensile strength of the composite films were investigated. Swelling behaviour increased with alginate content, 50 % alginate film achieved 1254.75 % swelling after 24 h. All composite films achieved more than 80 % porosity except the film with 80 % collagen (65.41 %). Porosity was highest in 100 % alginate (94.30 %). Highest tensile strength (1585.87 kPa) and young modulus (27.05 MPa) was found in 50 % alginate film. In addition, resistance to collagenase degradation was improved with alginate content, lowest degradation rate was determined in 80 % alginate film. Results indicated alginate is efficient in improving some mechanical properties of the composite film.

  1. Collagenous mucosal inflammatory diseases of the gastrointestinal tract.

    Science.gov (United States)

    Freeman, Hugh J

    2005-07-01

    Collagenous mucosal inflammatory diseases involve the columnar-lined gastric and intestinal mucosa and have become recognized increasingly as a significant cause of symptomatic morbidity, particularly in middle-aged and elderly women, especially with watery diarrhea. Still, mechanisms involved in the pathogenesis of this diarrhea remain poorly understood and require further elucidation. The prognosis and long-term outcome of these disorders has been documented only to a limited extent. Recent clinical and pathologic studies have indicated that collagenous mucosal inflammatory disease is a more extensive pathologic process that concomitantly may involve several sites in the gastric and intestinal mucosa. The dominant pathologic lesion is a distinct subepithelial hyaline-like deposit that has histochemical and ultrastructural features of collagen overlying a microscopically defined inflammatory process. An intimate relationship with other autoimmune connective tissue disorders is evident, particularly celiac disease. This is intriguing because these collagenous disorders have not been shown to be gluten dependent. Collagenous mucosal inflammatory disorders may represent a relatively unique but generalized inflammatory response to a multitude of causes, including celiac disease, along with a diverse group of pharmacologic agents. Some recent reports have documented treatment success but histopathologic reversal has been more difficult to substantiate owing to the focal, sometimes extensive nature, of this pathologic process.

  2. Long-Term Natural History and Complications of Collagenous Colitis

    Directory of Open Access Journals (Sweden)

    Hugh J Freeman

    2012-01-01

    Full Text Available Microscopic forms of colitis have been described, including collagenous colitis, a possibly heterogeneous disorder. Collagenous colitis most often appears to have an entirely benign clinical course that usually responds to limited treatment. Sometimes significant extracolonic disorders, especially arthritis, spondylitis, thyroiditis and skin disorders, such as pyoderma gangrenosum, dominate the clinical course and influence the treatment strategy. However, rare fatalities have been reported and several complications, some severe, have been attributed directly to the colitis. Toxic colitis and toxic megacolon may develop. Concomitant gastric and small intestinal inflammatory disorders have been described including celiac disease and more extensive collagenous inflammatory disease. Colonic ulceration has been associated with the use of nonsteroidal anti-inflammatory drugs, while other forms of inflammatory bowel disease, including ulcerative colitis and Crohn disease, may evolve directly from collagenous colitis. Submucosal ‘dissection’, colonic fractures, or mucosal tears and perforation, possibly from air insufflation during colonoscopy, have been reported. Similar changes may result from increased intraluminal pressures that may occur during radiological imaging of the colon. Neoplastic disorders of the colon may also occur during the course of collagenous colitis, including colon carcinoma and neuroendocrine tumours (ie, carcinoids. Finally, lymphoproliferative disease has been reported.

  3. Endogenous collagen influences differentiation of human multipotent mesenchymal stromal cells.

    Science.gov (United States)

    Fernandes, Hugo; Mentink, Anouk; Bank, Ruud; Stoop, Reinout; van Blitterswijk, Clemens; de Boer, Jan

    2010-05-01

    Human multipotent mesenchymal stromal cells (hMSCs) are multipotent cells that, in the presence of appropriate stimuli, can differentiate into different lineages such as the osteogenic, chondrogenic, and adipogenic lineages. In the presence of ascorbic acid, MSCs secrete an extracellular matrix mainly composed of collagen type I. Here we assessed the potential role of endogenous collagen synthesis in hMSC differentiation and stem cell maintenance. We observed a sharp reduction in proliferation rate of hMSCs in the absence of ascorbic acid, concomitant with a reduction in osteogenesis in vitro and bone formation in vivo. In line with a positive role for collagen type I in osteogenesis, gene expression profiling of hMSCs cultured in the absence of ascorbic acid demonstrated increased expression of genes involved in adipogenesis and chondrogenesis and a reduction in expression of osteogenic genes. We also observed that matrix remodeling and anti-osteoclastogenic signals were high in the presence of ascorbic acid. The presence of collagen type I during the expansion phase of hMSCs did not affect their osteogenic and adipogenic differentiation potential. In conclusion, the collagenous matrix supports both proliferation and differentiation of osteogenic hMSCs but, on the other hand, presents signals stimulating matrix remodeling and inhibiting osteoclastogenesis.

  4. Electrochemical deposition of mineralized BSA/collagen coating

    Energy Technology Data Exchange (ETDEWEB)

    Zhuang, Junjun [School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); Lin, Jun; Li, Juan; Wang, Huiming [The First Affiliated Hospital of Medical College, Zhejiang University, Hangzhou 310003 (China); Cheng, Kui [School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); Weng, Wenjian, E-mail: wengwj@zju.edu.cn [School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); The Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China)

    2016-09-01

    In this work, mineralized collagen coatings with different loading quantity of bovine serum albumin (BSA) were prepared via in situ electrochemical deposition on titanium substrate. The microstructure and BSA loading quantity of the coatings could be controlled by the electrochemical deposition parameters, such as deposition potential, BSA concentration and its adding sequence in the electrolyte. The BSA loading quantity in the coatings was obtained in the range of 0.0170–0.173 mg/cm{sup 2}, enhancing the cell adhesion and proliferation of the coatings with the simultaneous release. The distinct release behaviors of BSA were attributed to their gradient distribution with different mineralization degrees, which could be adjusted by the deposition process. These results suggest that in situ electrochemical deposition is a promising way to incorporate functional molecules into the mineralized collagen coatings and the mineralized BSA/collagen coatings are highly promising for improving the rhBMP-2 loading capability (1.8-fold). - Highlights: • BSA is incorporated into mineralized collagen coating by electrochemical deposition. • The loading amount of BSA in coatings can be adjusted in the range of 0-173 ng. • The BSA/collagen coating shows good cytocompatibility with free-albumin culture. • The incorporation process is put forward for some other molecules deposition.

  5. Cyclophilin B Deficiency Causes Abnormal Dentin Collagen Matrix.

    Science.gov (United States)

    Terajima, Masahiko; Taga, Yuki; Cabral, Wayne A; Nagasawa, Masako; Sumida, Noriko; Hattori, Shunji; Marini, Joan C; Yamauchi, Mitsuo

    2017-08-04

    Cyclophilin B (CypB) is an endoplasmic reticulum-resident protein that regulates collagen folding, and also contributes to prolyl 3-hydroxylation (P3H) and lysine (Lys) hydroxylation of collagen. In this study, we characterized dentin type I collagen in CypB null (KO) mice, a model of recessive osteogenesis imperfecta type IX, and compared to those of wild-type (WT) and heterozygous (Het) mice. Mass spectrometric analysis demonstrated that the extent of P3H in KO collagen was significantly diminished compared to WT/Het. Lys hydroxylation in KO was significantly diminished at the helical cross-linking sites, α1/α2(I) Lys-87 and α1(I) Lys-930, leading to a significant increase in the under-hydroxylated cross-links and a decrease in fully hydroxylated cross-links. The extent of glycosylation of hydroxylysine residues was, except α1(I) Lys-87, generally higher in KO than WT/Het. Some of these molecular phenotypes were distinct from other KO tissues reported previously, indicating the dentin-specific control mechanism through CypB. Histological analysis revealed that the width of predentin was greater and irregular, and collagen fibrils were sparse and significantly smaller in KO than WT/Het. These results indicate a critical role of CypB in dentin matrix formation, suggesting a possible association between recessive osteogenesis imperfecta and dentin defects that have not been clinically detected.

  6. Computational model of collagen turnover in carotid arteries during hypertension.

    Science.gov (United States)

    Sáez, P; Peña, E; Tarbell, J M; Martínez, M A

    2015-02-01

    It is well known that biological tissues adapt their properties because of different mechanical and chemical stimuli. The goal of this work is to study the collagen turnover in the arterial tissue of hypertensive patients through a coupled computational mechano-chemical model. Although it has been widely studied experimentally, computational models dealing with the mechano-chemical approach are not. The present approach can be extended easily to study other aspects of bone remodeling or collagen degradation in heart diseases. The model can be divided into three different stages. First, we study the smooth muscle cell synthesis of different biological substances due to over-stretching during hypertension. Next, we study the mass-transport of these substances along the arterial wall. The last step is to compute the turnover of collagen based on the amount of these substances in the arterial wall which interact with each other to modify the turnover rate of collagen. We simulate this process in a finite element model of a real human carotid artery. The final results show the well-known stiffening of the arterial wall due to the increase in the collagen content. Copyright © 2015 John Wiley & Sons, Ltd.

  7. Can green solvents be alternatives for thermal stabilization of collagen?

    Science.gov (United States)

    Mehta, Ami; Rao, J Raghava; Fathima, Nishter Nishad

    2014-08-01

    "Go Green" campaign is gaining light for various industrial applications where water consumption needs to be reduced. To resolve this, industries have adopted usage of green, organic solvents, as an alternative to water. For leather making, tanning industry consumes gallons of water. Therefore, for adopting green solvents in leather making, it is necessary to evaluate its influence on type I collagen, the major protein present in the skin matrix. The thermal stability of collagen from rat tail tendon fiber (RTT) treated with seven green solvents namely, ethanol, ethyl lactate, ethyl acetate, propylene carbonate, propylene glycol, polyethylene glycol-200 and heptane was determined using differential scanning calorimetry (DSC). Crosslinking efficiency of basic chromium sulfate and wattle on RTT in green solvents was determined. DSC thermograms show increase in thermal stability of RTT collagen against heat with green solvents (>78°C) compared to water (63°C). In the presence of crosslinkers, RTT demonstrated thermal stability >100°C in some green solvents, resulting in increased intermolecular forces between collagen, solvent and crosslinkers. The significant improvement in thermal stability of collagen potentiates the capability of green solvents as an alternative for water. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Biological effect of hydrolyzed collagen on bone metabolism.

    Science.gov (United States)

    Daneault, Audrey; Prawitt, Janne; Fabien Soulé, Véronique; Coxam, Véronique; Wittrant, Yohann

    2017-06-13

    Osteoporosis is a chronic and asymptomatic disease characterized by low bone mass and skeletal microarchitectural deterioration, increased risk of fracture, and associated comorbidities most prevalent in the elderly. Due to an increasingly aging population, osteoporosis has become a major health issue requiring innovative disease management. Proteins are important for bone by providing building blocks and by exerting specific regulatory function. This is why adequate protein intake plays a considerable role in both bone development and bone maintenance. More specifically, since an increase in the overall metabolism of collagen can lead to severe dysfunctions and a more fragile bone matrix and because orally administered collagen can be digested in the gut, cross the intestinal barrier, enter the circulation, and become available for metabolic processes in the target tissues, one may speculate that a collagen-enriched diet provides benefits for the skeleton. Collagen-derived products such as gelatin or hydrolyzed collagen (HC) are well acknowledged for their safety from a nutritional point of view; however, what is their impact on bone biology? In this manuscript, we critically review the evidence from literature for an effect of HC on bone tissues in order to determine whether HC may represent a relevant alternative in the design of future nutritional approaches to manage osteoporosis prevention.

  9. Fusion Power Demonstration III

    International Nuclear Information System (INIS)

    Lee, J.D.

    1985-07-01

    This is the third in the series of reports covering the Fusion Power Demonstration (FPD) design study. This volume considers the FPD-III configuration that incorporates an octopole end plug. As compared with the quadrupole end-plugged designs of FPD-I and FPD-II, this octopole configuration reduces the number of end cell magnets and shortens the minimum ignition length of the central cell. The end-cell plasma length is also reduced, which in turn reduces the size and cost of the end cell magnets and shielding. As a contiuation in the series of documents covering the FPD, this report does not stand alone as a design description of FPD-III. Design details of FPD-III subsystems that do not differ significantly from those of the FPD-II configuration are not duplicated in this report

  10. III-V microelectronics

    CERN Document Server

    Nougier, JP

    1991-01-01

    As is well known, Silicon widely dominates the market of semiconductor devices and circuits, and in particular is well suited for Ultra Large Scale Integration processes. However, a number of III-V compound semiconductor devices and circuits have recently been built, and the contributions in this volume are devoted to those types of materials, which offer a number of interesting properties. Taking into account the great variety of problems encountered and of their mutual correlations when fabricating a circuit or even a device, most of the aspects of III-V microelectronics, from fundamental p

  11. Motor physical therapy affects muscle collagen type I and decreases gait speed in dystrophin-deficient dogs.

    Directory of Open Access Journals (Sweden)

    Thaís P Gaiad

    Full Text Available Golden Retriever Muscular Dystrophy (GRMD is a dystrophin-deficient canine model genetically homologous to Duchenne Muscular Dystrophy (DMD in humans. Muscular fibrosis secondary to cycles of degeneration/regeneration of dystrophic muscle tissue and muscular weakness leads to biomechanical adaptation that impairs the quality of gait. Physical therapy (PT is one of the supportive therapies available for DMD, however, motor PT approaches have controversial recommendations and there is no consensus regarding the type and intensity of physical therapy. In this study we investigated the effect of physical therapy on gait biomechanics and muscular collagen deposition types I and III in dystrophin-deficient dogs. Two dystrophic dogs (treated dogs-TD underwent a PT protocol of active walking exercise, 3×/week, 40 minutes/day, 12 weeks. Two dystrophic control dogs (CD maintained their routine of activities of daily living. At t0 (pre and t1 (post-physical therapy, collagen type I and III were assessed by immunohistochemistry and gait biomechanics were analyzed. Angular displacement of shoulder, elbow, carpal, hip, stifle and tarsal joint and vertical (Fy, mediolateral (Fz and craniocaudal (Fx ground reaction forces (GRF were assessed. Wilcoxon test was used to verify the difference of biomechanical variables between t0 and t1, considering p<.05. Type I collagen of endomysium suffered the influence of PT, as well as gait speed that had decreased from t0 to t1 (p<.000. The PT protocol employed accelerates morphological alterations on dystrophic muscle and promotes a slower velocity of gait. Control dogs which maintained their routine of activities of daily living seem to have found a better balance between movement and preservation of motor function.

  12. Motor Physical Therapy Affects Muscle Collagen Type I and Decreases Gait Speed in Dystrophin-Deficient Dogs

    Science.gov (United States)

    Gaiad, Thaís P.; Araujo, Karla P. C.; Serrão, Júlio C.; Miglino, Maria A.; Ambrósio, Carlos Eduardo

    2014-01-01

    Golden Retriever Muscular Dystrophy (GRMD) is a dystrophin-deficient canine model genetically homologous to Duchenne Muscular Dystrophy (DMD) in humans. Muscular fibrosis secondary to cycles of degeneration/regeneration of dystrophic muscle tissue and muscular weakness leads to biomechanical adaptation that impairs the quality of gait. Physical therapy (PT) is one of the supportive therapies available for DMD, however, motor PT approaches have controversial recommendations and there is no consensus regarding the type and intensity of physical therapy. In this study we investigated the effect of physical therapy on gait biomechanics and muscular collagen deposition types I and III in dystrophin-deficient dogs. Two dystrophic dogs (treated dogs-TD) underwent a PT protocol of active walking exercise, 3×/week, 40 minutes/day, 12 weeks. Two dystrophic control dogs (CD) maintained their routine of activities of daily living. At t0 (pre) and t1 (post-physical therapy), collagen type I and III were assessed by immunohistochemistry and gait biomechanics were analyzed. Angular displacement of shoulder, elbow, carpal, hip, stifle and tarsal joint and vertical (Fy), mediolateral (Fz) and craniocaudal (Fx) ground reaction forces (GRF) were assessed. Wilcoxon test was used to verify the difference of biomechanical variables between t0 and t1, considering p<.05. Type I collagen of endomysium suffered the influence of PT, as well as gait speed that had decreased from t0 to t1 (p<.000). The PT protocol employed accelerates morphological alterations on dystrophic muscle and promotes a slower velocity of gait. Control dogs which maintained their routine of activities of daily living seem to have found a better balance between movement and preservation of motor function. PMID:24713872

  13. Thermal helix-coil transition in UV irradiated collagen from rat tail tendon.

    Science.gov (United States)

    Sionkowska, A; Kamińska, A

    1999-05-01

    The thermal helix-coil transition in UV irradiated collagen solution, collagen film and pieces of rat tail tendon (RTT) were compared. Their thermal stability's were determined by differential scanning calorimeter (DSC) and by viscometric measurements. The denaturation temperatures of collagen solution, film and pieces of RTT were different. The helix-coil transition occur near 40 degrees C in collagen solution, near 112 degrees C in collagen film, and near 101 degrees C in pieces of RTT. After UV irradiation the thermal helix-coil transition of collagen samples were changed. These changes depend on the degree of hydratation.

  14. Photo-induced processes in collagen-hypericin system revealed by fluorescence spectroscopy and multiphoton microscopy.

    Science.gov (United States)

    Hovhannisyan, V; Guo, H W; Hovhannisyan, A; Ghukasyan, V; Buryakina, T; Chen, Y F; Dong, C Y

    2014-05-01

    Collagen is the main structural protein and the key determinant of mechanical and functional properties of tissues and organs. Proper balance between synthesis and degradation of collagen molecules is critical for maintaining normal physiological functions. In addition, collagen influences tumor development and drug delivery, which makes it a potential cancer therapy target. Using second harmonic generation, two-photon excited fluorescence microscopy, and spectrofluorimetry, we show that the natural pigment hypericin induces photosensitized destruction of collagen-based tissues. We demonstrate that hypericin-mediated processes in collagen fibers are irreversible and may be used for the treatment of cancer and collagen-related disorders.

  15. The collagen receptor uPARAP/Endo180 in tissue degradation and cancer (Review)

    DEFF Research Database (Denmark)

    Carlsen Melander, Eva Maria; Jürgensen, Henrik J; Madsen, Daniel H

    2015-01-01

    The collagen receptor uPARAP/Endo180, the product of the MRC2 gene, is a central component in the collagen turnover process governed by various mesenchymal cells. Through the endocytosis of collagen or large collagen fragments, this recycling receptor serves to direct basement membrane collagen...... as well as interstitial collagen to lysosomal degradation. This capacity, shared only with the mannose receptor from the same protein family, endows uPARAP/Endo180 with a critical role in development and homeostasis, as well as in pathological disruptions of the extracellular matrix structure. Important...

  16. Tumor-Associated Macrophages Derived from Circulating Inflammatory Monocytes Degrade Collagen through Cellular Uptake

    DEFF Research Database (Denmark)

    Madsen, Daniel Hargbøl; Jürgensen, Henrik Jessen; Siersbæk, Majken Storm

    2017-01-01

    -associated macrophage (TAM)-like cells that degrade collagen in a mannose receptor-dependent manner. Accordingly, mannose-receptor-deficient mice display increased intratumoral collagen. Whole-transcriptome profiling uncovers a distinct extracellular matrix-catabolic signature of these collagen-degrading TAMs. Lineage......-ablation studies reveal that collagen-degrading TAMs originate from circulating CCR2+ monocytes. This study identifies a function of TAMs in altering the tumor microenvironment through endocytic collagen turnover and establishes macrophages as centrally engaged in tumor-associated collagen degradation. Madsen et...

  17. Visualisation of collagen fibrils in joint cartilage using STIM

    International Nuclear Information System (INIS)

    Reinert, T.; Reibetanz, U.; Vogt, J.; Butz, T.; Werner, A.; Gruender, W.

    2001-01-01

    The scanning transmission ion microscopy (STIM) method was used to investigate the collagen network structure of the articular cartilage from a pig's knee in comparison with high resolution nuclear magnetic resonance imaging (microscopic NMR-tomography) and polarised light microscopy (PLM). Single collagen fibrils down to 200 nm in diameter were visualised. It was proved that the cartilage collagen network consists partly of zones of oriented fibrils as suggested by NMR measurements. Radially oriented fibrils were found in the zone near the calcified zone (hypertrophic zone) of both tibia and femur, and in the tibial radial zone. Tangentially oriented fibrils were found in the femoral and tibial superficial zone and in a second zone of the femoral cartilage. Polarisation light microscopy reveals broader zones of orientation than it was found with STIM

  18. A role for collagen IV in cardiovascular disease?

    DEFF Research Database (Denmark)

    Steffensen, Lasse Bach; Rasmussen, Lars M

    2018-01-01

    Over the past decade, studies have repeatedly found single nucleotide polymorphisms located in the COL4A1 and COL4A2 genes to be associated with cardiovascular disease (CVD), and the 13q34 locus harboring these genes is one of approximately 160 genome-wide significant risk loci for coronary artery...... disease. COL4A1 and COL4A2 encode the ⍺1- and ⍺2-chains of collagen IV, a major component of basement membranes in various tissues including arteries. In spite of the growing body of evidence indicating a role for collagen IV in CVD, remarkably few studies aim at directly investigating such a role....... The purpose of this review is to summarize the clinical reports linking 13q34 to coronary artery disease, atherosclerosis and artery stiffening and to assemble the scattered pieces of evidence from experimental studies based on vascular cells and -tissue collectively supporting a role for collagen IV...

  19. Characterization of collagen / chitosan films for skin regenerating scaffold

    International Nuclear Information System (INIS)

    Ismarul, I.N.; Ishak, Y.; Ismail, Z.; Mohd Shalihuddin, W.M.

    2004-01-01

    Various Proportions of chitosan/collagen films (70/30% to 95/05%) w/w were prepared and evaluated for its suitability as skin regenerating scaffold. Interactions between chitosan and collagen were studied using Fourier Transform Infrared spectroscopy (FTIR) and Differential Scanning Colorimetry (DSC). Scanning Electron Microscope (SEM) was used to investigate the morphology of the blend. Mechanical properties were evaluated using a Universal Testing Machine (UTM). The chitosan/collagen films were found to swell proportionally with time until it reaches equilibrium, FTIR spectroscopy indicated no chemical interaction between the components of the blends, DSC data indicated only one peak proving that these two materials are compatible at all proportions investigated. SEM micrographs also indicated good homogeneity between these two materials. (Author)

  20. Preparation and characterization of collagen-hydroxyapatite/pectin composite.

    Science.gov (United States)

    Wenpo, Feng; Gaofeng, Liang; Shuying, Feng; Yuanming, Qi; Keyong, Tang

    2015-03-01

    Pectin, a kind of plant polysaccharide, was introduced into collagen-hydroxyapatite composite system, and prepared collagen-hydroxyapatite/pectin (Col-HA/pectin) composite in situ. The structure of the composite was investigated by XRD, SEM, and FT-IR. The mechanical properties, water absorption, enzyme degradation, and cytotoxicity of the composite were investigated as well. The results show that the inorganic substance in the composite materials is hydroxyapatite in relatively low crystallinity. A new interface appeared by the interaction among hydroxyapatite and collagen-pectin, and formed smooth fine particles. The mechanical properties, water absorption, enzyme degradation, and cytotoxicity indicate a potential use in bone replacement for the new composite. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Imaging of collagen deposition disorders using optical coherence tomography

    DEFF Research Database (Denmark)

    Ring, H C; Mogensen, M; Hussain, A A

    2015-01-01

    BACKGROUND: Collagen deposition disorders such as hypertrophic scars, keloids and scleroderma can be associated with significant stigma and embarrassment. These disorders often constitute considerable impairment to quality of life, with treatment posing to be a substantial challenge. Optical...... lesion type. Hypertrophic scars displayed an increased vascularity and signal-rich bands correlating to excessive collagen deposition. Keloids depicted a disarray of hyper-reflective areas primarily located in the upper dermis. Additionally, the dermis displayed a heterogeneous morphology without...... indications of any vascular supply or lymphatic network. In contrast to keloids, scleroderma displayed a more cohesive backscattering indicating a difference in density of collagen or other dermal structures. OCT images demonstrated no significant differences between mean density measurements in OCT images...

  2. Dielectric relaxation in solid collagen over a wide temperature range

    International Nuclear Information System (INIS)

    Khan, Muhammad Abdullah; Rizvi, Tasneem Zahra; Janjua, Khalid Mehmood; Zaheer, Muhammad Yar

    2001-07-01

    Dielectric constant ε' and loss factor ε'' have been measured in bovine tendon collagen in the frequency range 30 Hz - 3 MHz and temperature range 30 deg. C to 200 deg. C. Frequency dependence curve of ε'' shows a low frequency strong α-dispersion attributed to phonon assisted proton hopping between localized sites and a weak high frequency. α 2 - dispersion attributed to reorientation of polar components of collagen molecules. Temperature dependence of the dielectric data show release of bound moisture as a three step process with discrete peaks at 50 deg. C, 90 deg. C and 125 deg. C. These peaks have been attributed to release of adsorbed surface water, water bound to exposed polar sites and strongly bound internal moisture respectively. A peak observed at 160 deg. C has been attributed to thermally induced helix-coil transition of collagen molecules. (author)

  3. Systemic and local collagen turnover in hernia patients

    DEFF Research Database (Denmark)

    Henriksen, Nadia A

    2016-01-01

    composition appears altered in fascial tissue but also in skin biopsies, suggesting that the collagen alterations are systemic. More pronounced collagen alterations are found in patients with hernia recurrences. Hypothetically, primary inguinal hernias are formed due to a systemic predisposition to altered...... connective tissue, whereas impaired healing influences on the development of incisional hernias and hernia recurrences. The overall objective of this thesis was to investigate the collagen turnover systemically and locally in patients with primary inguinal hernia, multiple hernias and incisional hernia...... repair after adjustment for gender, age and surgical approach. In a multivariable subgroup analysis, direct and recurrent inguinal hernia repair were associated with primary ventral hernia surgery, whereas only recurrent inguinal hernia repair was associated with secondary ventral hernia surgery...

  4. Serum aminoterminal type III procollagen peptide reflects repair after acute myocardial infarction

    DEFF Research Database (Denmark)

    Jensen, L T; Hørslev-Petersen, K; Toft, P

    1990-01-01

    similar to changes observed during wound healing in humans. PIIINP is cleaved off procollagen type III during the biosynthesis of type III collagen, which characterizes the early stages of repair and inflammation. Our findings suggest that serum PIIINP reflects the repair processes and scar formation...... following acute myocardial infarction. The serum PIIINP alterations in acute myocardial infarction differ essentially from the changes in myocardial enzymes reflecting myocardial injury. Serum PIIINP may therefore provide new and clinically relevant information on the healing of myocardial infarction....

  5. Epac is required for exogenous and endogenous stimulation of adenosine A2B receptor for inhibition of angiotensin II-induced collagen synthesis and myofibroblast differentiation.

    Science.gov (United States)

    Phosri, Sarawuth; Bunrukchai, Kwanchai; Parichatikanond, Warisara; Sato, Vilasinee H; Mangmool, Supachoke

    2018-01-10

    Angiotensin II (Ang II) plays an important role on the pathogenesis of cardiac fibrosis. Prolong and overstimulation of angiotensin II type 1 receptor with Ang II-induced collagen synthesis and myofibroblast differentiation in cardiac fibroblasts, leading to cardiac fibrosis. Although adenosine and its analogues are known to have cardioprotective effects, the mechanistic by which adenosine A 2 receptors (A 2 Rs) inhibit Ang II-induced cardiac fibrosis is not clearly understood. In the present study, we examined the effects of exogenous adenosine and endogenous adenosine on Ang II-induced collagen and myofibroblast differentiation determined by α-smooth muscle action (α-SMA) overexpression and their underlying signal transduction. Elevation of endogenous adenosine levels resulted in the inhibition of Ang II-induced collagen type I and III and α-SMA synthesis in cardiac fibroblasts. Moreover, treatment with exogenous adenosine which selectively stimulated A 2 Rs also suppressed Ang II-induced collagen synthesis and α-SMA production. These antifibrotic effects of both endogenous and exogenous adenosines are mediated through the A 2B receptor (A 2B R) subtype. Stimulation of A 2B R exhibited antifibrotic effects via the cAMP-dependent and Epac-dependent pathways. Our results provide new mechanistic insights regarding the role for cAMP and Epac on A 2B R-mediated antifibrotic effects. Thus, A 2B R is one of the potential therapeutic targets against cardiac fibrosis.

  6. Collagen concentration on the facial skin of postmenopausal women after topical treatment with estradiol and genistein: a randomized double-blind controlled trial.

    Science.gov (United States)

    Silva, Lidia Aragão; Ferraz Carbonel, Adriana Aparecida; de Moraes, Andréa Regina Barbosa; Simões, Ricardo S; Sasso, Gisela Rodrigues da Silva; Goes, Lívia; Nunes, Winnie; Simões, Manuel Jesus; Patriarca, Marisa Teresinha

    2017-11-01

    The objective of this study is to compare the effects of topical estrogen and genistein (a soy isoflavone) on the facial skin collagen of postmenopausal women not undergoing systemic hormonal therapy. This is a prospective, double blind, randomized, controlled clinical trial. Volunteer women (N = 30) 45-55 year old from the Endocrine Gynecology sector of the Gynecology Department of the Federal University of São Paulo (UNIFESP). The Ethical Committee of the Federal University of São Paulo approved the study (report no. 386/2004; registration on ClinicalTrials.gov NCT01553773), were assigned to topical treatment with either estrogen or genistein for 24 weeks. We quantified and compared facial collagen concentration before and after each treatment by performing pre-auricular skin biopsies. Our data showed an increase in the amount of both type I and type III facial collagen by the end of both treatments. However, the outcomes of the estrogen GI (ER) group were superior to the genistein GII (GEN) group, with statistical significance p < 000.1 Conclusion: Treatment with topical estrogen is superior to genistein, but both have positive impacts on facial skin collagen. Nevertheless, it is still unclear whether prolonged use of genistein and other topical phytoestrogens could produce systemic effects and further research is needed to clarify this question.

  7. Summary of Session III

    International Nuclear Information System (INIS)

    Furman, M.A.

    2002-01-01

    This is a summary of the talks presented in Session III ''Simulations of Electron-Cloud Build Up'' of the Mini-Workshop on Electron-Cloud Simulations for Proton and Positron Beams ECLOUD-02, held at CERN, 15-18 April 2002

  8. Comparative proteomic analysis of normal and collagen IX null mouse cartilage reveals altered extracellular matrix composition and novel components of the collagen IX interactome.

    Science.gov (United States)

    Brachvogel, Bent; Zaucke, Frank; Dave, Keyur; Norris, Emma L; Stermann, Jacek; Dayakli, Münire; Koch, Manuel; Gorman, Jeffrey J; Bateman, John F; Wilson, Richard

    2013-05-10

    Collagen IX is an integral cartilage extracellular matrix component important in skeletal development and joint function. Proteomic analysis and validation studies revealed novel alterations in collagen IX null cartilage. Matrilin-4, collagen XII, thrombospondin-4, fibronectin, βig-h3, and epiphycan are components of the in vivo collagen IX interactome. We applied a proteomics approach to advance our understanding of collagen IX ablation in cartilage. The cartilage extracellular matrix is essential for endochondral bone development and joint function. In addition to the major aggrecan/collagen II framework, the interacting complex of collagen IX, matrilin-3, and cartilage oligomeric matrix protein (COMP) is essential for cartilage matrix stability, as mutations in Col9a1, Col9a2, Col9a3, Comp, and Matn3 genes cause multiple epiphyseal dysplasia, in which patients develop early onset osteoarthritis. In mice, collagen IX ablation results in severely disturbed growth plate organization, hypocellular regions, and abnormal chondrocyte shape. This abnormal differentiation is likely to involve altered cell-matrix interactions but the mechanism is not known. To investigate the molecular basis of the collagen IX null phenotype we analyzed global differences in protein abundance between wild-type and knock-out femoral head cartilage by capillary HPLC tandem mass spectrometry. We identified 297 proteins in 3-day cartilage and 397 proteins in 21-day cartilage. Components that were differentially abundant between wild-type and collagen IX-deficient cartilage included 15 extracellular matrix proteins. Collagen IX ablation was associated with dramatically reduced COMP and matrilin-3, consistent with known interactions. Matrilin-1, matrilin-4, epiphycan, and thrombospondin-4 levels were reduced in collagen IX null cartilage, providing the first in vivo evidence for these proteins belonging to the collagen IX interactome. Thrombospondin-4 expression was reduced at the mRNA level

  9. An evaluation of meniscal collagenous structure using optical projection tomography

    International Nuclear Information System (INIS)

    Andrews, Stephen HJ; Ronsky, Janet L; Rattner, Jerome B; Shrive, Nigel G; Jamniczky, Heather A

    2013-01-01

    The collagenous structure of menisci is a complex network of circumferentially oriented fascicles and interwoven radially oriented tie-fibres. To date, examination of this micro- architecture has been limited to two-dimensional imaging techniques. The purpose of this study was to evaluate the ability of the three-dimensional imaging technique; optical projection tomography (OPT), to visualize the collagenous structure of the meniscus. If successful, this technique would be the first to visualize the macroscopic orientation of collagen fascicles in 3-D in the meniscus and could further refine load bearing mechanisms in the tissue. OPT is an imaging technique capable of imaging samples on the meso-scale (1-10 mm) at a micro-scale resolution. The technique, similar to computed tomography, takes two-dimensional images of objects from incremental angles around the object and reconstructs them using a back projection algorithm to determine three-dimensional structure. Bovine meniscal samples were imaged from four locations (outer main body, femoral surface, tibial surface and inner main body) to determine the variation in collagen orientation throughout the tissue. Bovine stifles (n = 2) were obtained from a local abattoir and the menisci carefully dissected. Menisci were fixed in methanol and subsequently cut using a custom cutting jig (n = 4 samples per meniscus). Samples were then mounted in agarose, dehydrated in methanol and subsequently cleared using benzyl alcohol benzyl benzoate (BABB) and imaged using OPT. Results indicate circumferential, radial and oblique collagenous orientations at the contact surfaces and in the inner third of the main body of the meniscus. Imaging identified fascicles ranging from 80-420 μm in diameter. Transition zones where fascicles were found to have a woven or braided appearance were also identified. The outer-third of the main body was composed of fascicles oriented predominantly in the circumferential direction. Blood vessels were

  10. Collagen-derived markers of bone metabolism in osteogenesis imperfecta

    DEFF Research Database (Denmark)

    Lund, A M; Hansen, M; Kollerup, Gina Birgitte

    1998-01-01

    )] were measured in 78 osteogenesis imperfecta (OI) patients to investigate bone metabolism in vivo and relate marker concentrations to phenotype and in vitro collagen I defects, as shown by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). PICP and PINP were generally low....... The in vivo findings correlated with in vitro results of collagen I SDS-PAGE. Bone turnover is reduced in OI children and mildly affected OI adults, whereas bone resorption is elevated in severely affected adults. These findings may prove helpful for diagnosis and decision-making regarding therapy in OI....

  11. Collagen XVIII Mutation in Knobloch Syndrome with Acute Lymphoblastic Leukemia

    Science.gov (United States)

    Mahajan, Vinit B.; Olney, Ann Haskins; Garrett, Penny; Chary, Ajit; Dragan, Ecaterina; Lerner, Gary; Murray, Jeffrey; Bassuk, Alexander G.

    2010-01-01

    Knobloch syndrome (KNO) is caused by mutations in the collagen XIII gene (COL18A1) and patients develop encephalocele and vitreoretinal degeneration. Here we report an El Salvadorian family where two sisters showed features of KNO. One of the siblings also developed acute lymphoblastic leukemia. DNA sequencing of COL18A1revealed a homozygous, 2-base pair deletion (c3514-3515delCT) in exon 41, which leads to abnormal collagen XVIII and deficiency of its proteolytic cleavage product endostatin. KNO patients with mutations in COL18A1 may be at risk for endostatin-related conditions including malignancy. PMID:20799329

  12. Differential effects of collagen prolyl 3-hydroxylation on skeletal tissues.

    Directory of Open Access Journals (Sweden)

    Erica P Homan

    2014-01-01

    Full Text Available Mutations in the genes encoding cartilage associated protein (CRTAP and prolyl 3-hydroxylase 1 (P3H1 encoded by LEPRE1 were the first identified causes of recessive Osteogenesis Imperfecta (OI. These proteins, together with cyclophilin B (encoded by PPIB, form a complex that 3-hydroxylates a single proline residue on the α1(I chain (Pro986 and has cis/trans isomerase (PPIase activity essential for proper collagen folding. Recent data suggest that prolyl 3-hydroxylation of Pro986 is not required for the structural stability of collagen; however, the absence of this post-translational modification may disrupt protein-protein interactions integral for proper collagen folding and lead to collagen over-modification. P3H1 and CRTAP stabilize each other and absence of one results in degradation of the other. Hence, hypomorphic or loss of function mutations of either gene cause loss of the whole complex and its associated functions. The relative contribution of losing this complex's 3-hydroxylation versus PPIase and collagen chaperone activities to the phenotype of recessive OI is unknown. To distinguish between these functions, we generated knock-in mice carrying a single amino acid substitution in the catalytic site of P3h1 (Lepre1(H662A . This substitution abolished P3h1 activity but retained ability to form a complex with Crtap and thus the collagen chaperone function. Knock-in mice showed absence of prolyl 3-hydroxylation at Pro986 of the α1(I and α1(II collagen chains but no significant over-modification at other collagen residues. They were normal in appearance, had no growth defects and normal cartilage growth plate histology but showed decreased trabecular bone mass. This new mouse model recapitulates elements of the bone phenotype of OI but not the cartilage and growth phenotypes caused by loss of the prolyl 3-hydroxylation complex. Our observations suggest differential tissue consequences due to selective inactivation of P3H1 hydroxylase

  13. Collagen synthesis in rat gingiva during tooth movement

    International Nuclear Information System (INIS)

    Boisson, M.; Gianelly, A.A.

    1981-01-01

    The response of the gingiva to an increased interdental space was studied by creating a diastema between the central incisors of rats and analyzing autoradiographically the incorporation of H3 proline in the gingiva to detect increased collagen production. In addition, conventional histologic methods were used to determine changes in the gingival architecture. The results indicate that the gingiva responds to an increased space in at least two ways. One is the production of more collagen fibers. The other involves the reorientation of the existing fibers in a horizontal plane as the gingival papilla becomes flattened

  14. Age-related changes in human tendo calcaneus collagen fibrils

    International Nuclear Information System (INIS)

    Sargon, Mustafa F.; Ozlu, Korhan; Oken, Fuad

    2005-01-01

    The ruptures of tendo calcaneus often occur between the age group of 30-45 years as described by several text books. It is also described that some diseases and drugs are said to be responsible in the etiology; however, there are no studies related with the detailed histological structure of collagen fibrils found in the tendon in the age groups of humans. In view there of, this study was aimed to obtain further information on the etiology and to find an answer regarding the frequency the ruptures occurring between the age of 30-45 years in human. In the study, the biopsy specimen taken from 28 patients age (1-68) years who had undergone surgery due to tendo calcaneus ruptures or acilloplasty operations were examined by transmission electron microscope. All the specimens were prepared according to routine electronic microscope tissue preparation technique. The patients were divided into 7 age groups (1-9, 10-19, 20-29, 30-39, 40-49, 50-59, >60 years) and there were 4 patients in each group. The transverse diameters of collagen fibers were measured from the ultra thin sections and statistical analysis of the results were performed. The study was carried out in the electron microscopy laboratory of the Anatomy Department of Hacettepe University, Ankara, Turkey between January 2004 and September 2004. The diameters of the collagen fibers were higher in the 20-29 year-old groups compared to other groups and it showed a statistically significant difference. In patients who were in the 30-39 year old group or older, the diameters of the collagen fibers were lesser than the 20-29 year-old group. However, an increase was observed in the collagen fibril concentration of these groups. In examination of the specimens of patients who were under 20-year old, the diameter of the collagen fibers were less than 20-29 year -old group. The electron microscopic appearance of the tissue sample of a one year-old patient had a specific organization and in this patient, both the

  15. INFLUENCE OF TOBACCO, ALCOHOL AND DIABETES ON THE COLLAGEN OF CREMASTER MUSCLE IN PATIENTS WITH INGUINAL HERNIAS.

    Science.gov (United States)

    Módena, Sérgio Ferreira; Caldeira, Eduardo José; Peres, Marco Antonio O; Andreollo, Nelson Adami

    2016-01-01

    New findings point out that the mechanism of formation of the hernias can be related to the collagenous tissues, under activity of aggressive agents such as the tobacco, alcohol and diabetes. To analyze the collagen present in the cremaster muscle in patients with inguinal hernias, focusing the effect of tobacco, alcohol, and diabetes. Fifteen patients with inguinal hernia divided in three groups were studied: group I (n=5) was control; group II (n=5) were smokers and/or drinkers; and group III (n=5) had diabetes mellitus. All subjects were underwent to surgical repair of the inguinal hernias obeying the same pre, intra and postoperative conditions. During surgery, samples of the cremaster muscle were collected for analysis in polarized light microscopy, collagen morphometry and protein. The area occupied by the connective tissue was higher in groups II and III (ptabaco, o álcool e o diabete. Avaliar o colágeno presente no músculo cremaster em pacientes com hérnias inguinais enfocando o efeito do tabaco, álcool e diabete. Foram estudados 15 pacientes com hérnias inguinais divididos em: grupo I (n=5) controles; grupo II (n=5) indivíduos fumantes e/ou etilistas; e grupo III (n=5) indivíduos que apresentavam diabete melito. Todos foram submetidos à correção cirúrgica das hérnias inguinais obedecendo às mesmas condições pré, intra e pós-operatórias. Durante o procedimento cirúrgico, amostras do músculo cremaster foram coletadas para análises em microscopia de luz polarizada, morfometria do colágeno e de proteínas. A área ocupada por tecido conjuntivo foi maior nos grupos II e III (ptabaco, o álcool e o diabete ocasionam remodelação no músculo cremaster, levando à perda de suporte ou alteração estrutural nesta região, podendo intensificar as ocorrências e os danos relacionados às hérnias inguinais.

  16. INVIVO DEGRADATION OF PROCESSED DERMAL SHEEP COLLAGEN EVALUATED WITH TRANSMISSION ELECTRON-MICROSCOPY

    NARCIS (Netherlands)

    VANWACHEM, PB; VANLUYN, MJA; NIEUWENHUIS, P; KOERTEN, HK; DAMINK, LO; TENHOOPEN, H; FEIJEN, J

    The in vivo degradation of hexamethylenediisocyanate-tanned dermal sheep collagen was studied with transmission electron microscopy. Discs of hexamethylenediisocyanate-tanned dermal sheep collagen were subcutaneously implanted in rats. Both an intra- and an extracellular route of degradation could

  17. In vivo degradation of processed dermal sheep collagen evaluated with transmission electron microscopy

    NARCIS (Netherlands)

    van Wachem, P.B.; van Luyn, M.J.A.; Nieuwenhuis, P.; Koerten, H.K.; Olde damink, L.H.H.; Olde-Damink, L.; ten Hoopen, Hermina W.M.; Feijen, Jan

    1991-01-01

    The in vivo degradation of hexamethylenediisocyanate-tanned dermal sheep collagen was studied with transmission electron microscopy. Discs of hexamethylenediisocyanate-tanned dermal sheep collagen were subcutaneously implanted in rats. Both an intra- and an extracellular route of degradation could

  18. Modeling the impact of scaffold architecture and mechanical loading on collagen turnover in engineered cardiovascular tissues

    NARCIS (Netherlands)

    Argento, G.; de Jonge, N.; Söntjens, S.H.M.; Oomens, C.W.J.; Bouten, C.V.C.; Baaijens, F.P.T.

    2015-01-01

    The anisotropic collagen architecture of an engineered cardiovascular tissue has a major impact on its in vivo mechanical performance. This evolving collagen architecture is determined by initial scaffold microstructure and mechanical loading. Here, we developed and validated a theoretical and

  19. Synthesis of collagen by bovine chondrocytes cultured in alginate; posttranslational modifications and cell-matrix interaction

    NARCIS (Netherlands)

    Beekman, B.; Verzijl, N.; Bank, R.A.; Von Der Mark, K.; TeKoppele, J.M.

    1997-01-01

    The extracellular matrix synthesized by articular chondrocytes cultured in alginate beads was investigated. Collagen levels increased sigmoidally with time and remained constant after 2 weeks of culture. The presence of cartilage-specific type II collagen was confirmed immunohistochemically.

  20. Complementary roles of intracellular and pericellular collagen degradation pathways in vivo

    DEFF Research Database (Denmark)

    Wagenaar-Miller, Rebecca A; Engelholm, Lars H; Gavard, Julie

    2007-01-01

    Collagen degradation is essential for cell migration, proliferation, and differentiation. Two key turnover pathways have been described for collagen: intracellular cathepsin-mediated degradation and pericellular collagenase-mediated degradation. However, the functional relationship between these ...

  1. Collagen type II enhances chondrogenesis in adipose tissue-derived stem cells by affecting cell shape

    NARCIS (Netherlands)

    Lu, Z.; Doulabi, B.Z.; Huang, C.; Bank, R.A.; Helder, M.N.

    2010-01-01

    Ideally, biomaterials have inductive properties, favoring specific lineage differentiation. For chondrogenic induction, these properties have been attributed to collagen type II. However, the underlying mechanisms are largely unknown. This study aimed to investigate whether collagen type II favors

  2. Collagen Type II Enhances Chondrogenesis in Adipose Tissue-Derived Stem Cells by Affecting Cell Shape

    NARCIS (Netherlands)

    Lu, ZuFu; Doulabi, Behrouz Zandieh; Huang, ChunLing; Bank, Ruud A.; Helder, Marco N.

    Ideally, biomaterials have inductive properties, favoring specific lineage differentiation. For chondrogenic induction, these properties have been attributed to collagen type II. However, the underlying mechanisms are largely unknown. This study aimed to investigate whether collagen type II favors

  3. A 48 kDa collagen-binding phosphoprotein isolated from bovine aortic endothelial cells interacts with the collagenous domain, but not the globular domain, of collagen type IV.

    Science.gov (United States)

    Yannariello-Brown, J; Madri, J A

    1990-01-15

    We have identified collagen-binding proteins in detergent extracts of metabolically labelled bovine aortic endothelial cells (BAEC) by collagen type IV-Sepharose affinity chromatography. The major collagen type IV-binding protein identified by SDS/PAGE had a molecular mass of 48 kDa, which we term the 'collagen-binding 48 kDa protein' (CB48). The pI of CB48 was 8.0-8.3 in a two-dimensional gel system, running non-equilibrium pH gel electrophoresis in the first dimension and SDS/PAGE in the second dimension. Under these conditions CB48 separated into two major (a and b) and one minor isoform (c); a was the most basic of the three isoforms. Two-dimensional chymotryptic peptide maps derived from each individual isoform were virtually identical. The charge differences between the isoforms were due in part to differential H3(32)PO4 incorporation by the protein. CB48 bound to intact collagen type IV and the collagenous region of collagen type IV, but not to the globular NC1 domain. Cell-surface labelling and indirect immunofluorescence experiments localized the bulk of CB48 intracellularly in the endoplasmic reticulum Golgi region, with a minor population of molecules on the cell surface. A specific rabbit polyclonal anti-CB48 serum did not inhibit the attachment or spreading of BAEC to collagen type IV in an 'in vitro' adhesion assay, suggesting that the cell-surface population of CB48 is not involved in BAEC adhesion. We conclude that CB48 is a collagen-binding phosphoprotein that interacts with the collagenous domain of collagen type IV and may be involved in intracellular transport of collagen molecules.

  4. Evaluation of nanohydroxyapaptite (nano-HA) coated epigallocatechin-3-gallate (EGCG) cross-linked collagen membranes.

    Science.gov (United States)

    Chu, Chenyu; Deng, Jia; Man, Yi; Qu, Yili

    2017-09-01

    Collagen is the main component of extracellular matrix (ECM) with desirable biological activities and low antigenicity. Collagen materials have been widely utilized in guided bone regeneration (GBR) surgery due to its abilities to maintain space for hard tissue growth. However, pure collagen lacks optimal mechanical properties. In our previous study, epigallocatechin-3-gallate (EGCG) cross-linked collagen membranes, with better biological activities and enhanced mechanical properties, may promote osteoblast proliferation, but their effect on osteoblast differentiation is not very significant. Nanohydroxyapatite (nano-HA) is the main component of mineral bone, which possesses exceptional bioactivity properties including good biocompatibility, high osteoconductivity and osteoinductivity, non-immunogenicity and non-inflammatory behavior. Herein, by analyzing the physical and chemical properties as well as the effects on promoting bone regeneration, we have attempted to present a novel EGCG-modified collagen membrane with nano-HA coating, and have found evidence that the novel collagen membrane may promote bone regeneration with a better surface morphology, without destroying collagen backbone. To evaluate the surface morphologies, chemical and mechanical properties of pure collagen membranes, epigallocatechin-3-gallate (EGCG) cross-linked collagen membranes, nano-HA coated collagen membranes, nano-HA coated EGCG-collagen membranes, (ii) to evaluate the bone regeneration promoted by theses membranes. In the present study, collagen membranes were divided into 4 groups: (1) untreated collagen membranes (2) EGCG cross-linked collagen membranes (3) nano-HA modified collagen membranes (4) nano-HA modified EGCG-collagen membranes. Scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR) were used to evaluate surface morphologies and chemical properties, respectively. Mechanical properties were determined by differential scanning calorimeter (DSC

  5. GH receptor blocker administration and muscle-tendon collagen synthesis in humans

    DEFF Research Database (Denmark)

    Nielsen, Rie Harboe; Doessing, Simon; Goto, Kazushige

    2011-01-01

    The growth hormone (GH)/insulin-like growth factor-I (IGF-I) axis stimulates collagen synthesis in tendon and skeletal muscle, but no studies have investigated the effect of reducing IGF-I on collagen synthesis in healthy humans.......The growth hormone (GH)/insulin-like growth factor-I (IGF-I) axis stimulates collagen synthesis in tendon and skeletal muscle, but no studies have investigated the effect of reducing IGF-I on collagen synthesis in healthy humans....

  6. Ovine tendon collagen: Extraction, characterisation and fabrication of thin films for tissue engineering applications

    Energy Technology Data Exchange (ETDEWEB)

    Fauzi, M.B.; Lokanathan, Y. [Tissue Engineering Centre, UKM Medical Centre, Jalan Yaacob Latiff, Bandar Tun Razak, 56000 Cheras, Kuala Lumpur (Malaysia); Aminuddin, B.S. [Tissue Engineering Centre, UKM Medical Centre, Jalan Yaacob Latiff, Bandar Tun Razak, 56000 Cheras, Kuala Lumpur (Malaysia); Ear, Nose & Throat Consultant Clinic, Ampang Puteri Specialist Hospital, Taman Dato Ahmad Razali, 68000 Ampang, Selangor (Malaysia); Ruszymah, B.H.I. [Tissue Engineering Centre, UKM Medical Centre, Jalan Yaacob Latiff, Bandar Tun Razak, 56000 Cheras, Kuala Lumpur (Malaysia); Department of Physiology, UKM Medical Centre, Jalan Yaacob Latiff, Bandar Tun Razak, 56000 Cheras, Kuala Lumpur (Malaysia); Chowdhury, S.R., E-mail: shiplu@ppukm.ukm.edu.my [Tissue Engineering Centre, UKM Medical Centre, Jalan Yaacob Latiff, Bandar Tun Razak, 56000 Cheras, Kuala Lumpur (Malaysia)

    2016-11-01

    Collagen is the most abundant extracellular matrix (ECM) protein in the human body, thus widely used in tissue engineering and subsequent clinical applications. This study aimed to extract collagen from ovine (Ovis aries) Achilles tendon (OTC), and to evaluate its physicochemical properties and its potential to fabricate thin film with collagen fibrils in a random or aligned orientation. Acid-solubilized protein was extracted from ovine Achilles tendon using 0.35 M acetic acid, and 80% of extracted protein was measured as collagen. SDS-PAGE and mass spectrometry analysis revealed the presence of alpha 1 and alpha 2 chain of collagen type I (col I). Further analysis with Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS) confirms the presence of triple helix structure of col I, similar to commercially available rat tail col I. Drying the OTC solution at 37°C resulted in formation of a thin film with randomly orientated collagen fibrils (random collagen film; RCF). Introduction of unidirectional mechanical intervention using a platform rocker prior to drying facilitated the fabrication of a film with aligned orientation of collagen fibril (aligned collagen film; ACF). It was shown that both RCF and ACF significantly enhanced human dermal fibroblast (HDF) attachment and proliferation than that on plastic surface. Moreover, cells were distributed randomly on RCF, but aligned with the direction of mechanical intervention on ACF. In conclusion, ovine tendon could be an alternative source of col I to fabricate scaffold for tissue engineering applications. - Highlights: • Isolated collagen from ovine tendon was characterized as collagen type I. • Collagen film was fabricated via air drying of ovine tendon collagen. • Collagen fibril alignment was realized via unidirectional platform rocker. • Orientation of cells was attained depending on collagen fibril direction in the film. • Collagen films

  7. Some Biomaterials based on Collagen in Human Health care

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Some Biomaterials based on Collagen in Human Health care. Ophthalmology. Wound healing. Burn Dressing. Tumor Treatment. Tissue Engineered devices. for cardio-vascular functions; For managing chronic illnesses including diabetic ulcers and foot. Smart shoe.

  8. Studies on the comparative effect of sodium fluoride on collagen ...

    African Journals Online (AJOL)

    use

    2011-12-12

    Dec 12, 2011 ... (p < 0.05) higher collagen in the kidneys followed by lungs and liver. 5, 10 and 20 mg/kg .... the type of enzyme that is affected (Adamek et al., 2005). Fluoride at ... content of a diet may influence the food fluoride absorp- tion.

  9. Cross-linking of collagen-based materials

    NARCIS (Netherlands)

    Zeeman, R.

    1998-01-01

    An example of a collagen-based tissue is the aortic heart valve. A variety of pathological processes can lead to heart valve malfunction and this is usually associated with degenerative changes of the tissue. The most commonly used types of prosthetic valves are mechanical and tissue valves. One

  10. Temporal changes in collagen composition and metabolism during rodent palatogenesis

    NARCIS (Netherlands)

    Mansell, J.P.; Kerrigan, J.; McGill, J.; Bailey, J.; TeKoppele, J.; Sandy, J.R.

    2000-01-01

    Cleft lip and palate is a common craniofacial malformation in man. The aetiology is multifactorial and not known. Since collagen is a major structural component of the developing palate, we studied its composition and metabolism during palate shelf formation and elevation in the rat. Palatal shelves

  11. Surgical treatment of synovial-collagen disorders of the hand

    Directory of Open Access Journals (Sweden)

    H Kirk Watson

    2015-04-01

    Full Text Available Critical relationships between collagen and synovium exist and affect the function of the hand. Understanding these relationships enhances the ability to perform surgery including procedures addressing soft tissue and joint pathology. We present a series of surgical procedures based on this principle.

  12. Effect of Mechanical Stretching of the Skin on Collagen Fibril ...

    African Journals Online (AJOL)

    Dell

    MATERIALS AND METHODS. In vitro Skin Incubation. Samples of tissue were .... experimentally obtained melting curves. Calculation of the entropy of denaturation was ... Temperature (TD), enthalpy (ΔH) and entropy (ΔS) of denaturation of fibrils formed from type I collagen synthesized in the skin in the absence of tensile ...

  13. Metal Stabilization of Collagen and de Novo Designed Mimetic Peptides.

    Science.gov (United States)

    Parmar, Avanish S; Xu, Fei; Pike, Douglas H; Belure, Sandeep V; Hasan, Nida F; Drzewiecki, Kathryn E; Shreiber, David I; Nanda, Vikas

    2015-08-18

    We explore the design of metal binding sites to modulate triple-helix stability of collagen and collagen-mimetic peptides. Globular proteins commonly utilize metals to connect tertiary structural elements that are well separated in sequence, constraining structure and enhancing stability. It is more challenging to engineer structural metals into fibrous protein scaffolds, which lack the extensive tertiary contacts seen in globular proteins. In the collagen triple helix, the structural adjacency of the carboxy-termini of the three chains makes this region an attractive target for introducing metal binding sites. We engineered His3 sites based on structural modeling constraints into a series of designed homotrimeric and heterotrimeric peptides, assessing the capacity of metal binding to improve stability and in the case of heterotrimers, affect specificity of assembly. Notable enhancements in stability for both homo- and heteromeric systems were observed upon addition of zinc(II) and several other metal ions only when all three histidine ligands were present. Metal binding affinities were consistent with the expected Irving-Williams series for imidazole. Unlike other metals tested, copper(II) also bound to peptides lacking histidine ligands. Acetylation of the peptide N-termini prevented copper binding, indicating proline backbone amide metal-coordination at this site. Copper similarly stabilized animal extracted Type I collagen in a metal-specific fashion, highlighting the potential importance of metal homeostasis within the extracellular matrix.

  14. Electrospinning of collagen and elastin for tissue engineering applications

    NARCIS (Netherlands)

    Buttafoco, L.; Kolkman, N.G.; Engbers-Buijtenhuijs, P.; Poot, Andreas A.; Dijkstra, Pieter J.; Vermes, I.; Feijen, Jan

    2006-01-01

    Meshes of collagen and/or elastin were successfully prepared by means of electrospinning from aqueous solutions. Flow rate, applied electric field, collecting distance and composition of the starting solutions determined the morphology of the obtained fibres. Addition of PEO (Mw=8×106) and NaCl was

  15. MICROWAVE IRRADIATION AND CROSS-LINKING OF COLLAGEN

    NARCIS (Netherlands)

    VISSER, CE; VOUTE, ABE; OOSTING, J; BOON, ME; KOK, LP

    1992-01-01

    In a multifactorial experiment, dermal sheep collagen was treated in diluted glutaraldehyde solutions, 70% ethyl alcohol, Cialit 1:5000, and distilled water for 1, 3 and 5 min, respectively, in combination with microwave irradiation at different temperature settings. The shrinkage temperature

  16. Collagen attachment to the substrate controls cell clustering through migration

    International Nuclear Information System (INIS)

    Hou, Yue; Rodriguez, Laura Lara; Wang, Juan; Schneider, Ian C

    2014-01-01

    Cell clustering and scattering play important roles in cancer progression and tissue engineering. While the extracellular matrix (ECM) is known to control cell clustering, much of the quantitative work has focused on the analysis of clustering between cells with strong cell–cell junctions. Much less is known about how the ECM regulates cells with weak cell–cell contact. Clustering characteristics were quantified in rat adenocarcinoma cells, which form clusters on physically adsorbed collagen substrates, but not on covalently attached collagen substrates. Covalently attaching collagen inhibited desorption of collagen from the surface. While changes in proliferation rate could not explain differences seen in the clustering, changes in cell motility could. Cells plated under conditions that resulted in more clustering had a lower persistence time and slower migration rate than those under conditions that resulted in less clustering. Understanding how the ECM regulates clustering will not only impact the fundamental understanding of cancer progression, but also will guide the design of tissue engineered constructs that allow for the clustering or dissemination of cells throughout the construct. (paper)

  17. Collagen-derived markers of bone metabolism in osteogenesis imperfecta

    DEFF Research Database (Denmark)

    Lund, A M; Hansen, M; Kollerup, Gina Birgitte

    1998-01-01

    )] were measured in 78 osteogenesis imperfecta (OI) patients to investigate bone metabolism in vivo and relate marker concentrations to phenotype and in vitro collagen I defects, as shown by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). PICP and PINP were generally low...

  18. Dynamics of Cancer Cell near Collagen Fiber Chain

    Science.gov (United States)

    Kim, Jihan; Sun, Bo

    Cell migration is an integrated process that is important in life. Migration is essential for embryonic development as well as homeostatic processes such as wound healing and immune responses. When cell migrates through connective extracellular matrix (ECM), it applies cellular traction force to ECM and senses the rigidity of their local environment. We used human breast cancer cell (MDA-MB-231) which is highly invasive and applies strong traction force to ECM. As cancer cell applies traction force to type I collage-based ECM, it deforms collagen fibers near the surface. Patterns of deforming collagen fibers are significantly different with pairs of cancer cells compared to a single cancer cell. While a pair of cancer cells within 60 um creates aligned collagen fiber chains between them permanently, a single cancer cell does not form any fiber chains. In this experiment we measured a cellular response and an interaction between a pair of cells through the chain. Finally, we analyzed correlation of directions between cancer cell migration and the collagen chain alignment.

  19. Comparison of collagen profile and tenderness of muscles from ...

    African Journals Online (AJOL)

    Calving and age at slaughter did not influence cooking loss of semimembranosus (SEM) and infraspinatus (INF) muscles or the shear force of SEM. The ventral part of the INF muscle from single-calf cows exhibited higher shear force values. In both muscles, higher water-soluble and lower acid-soluble collagen contents ...

  20. Determination of activated plasma fibronectin using radioactive labelled collagen I

    DEFF Research Database (Denmark)

    Fenger, M

    1984-01-01

    The plasma concentration of biological active fibronectin was assayed by a protein binding assay using 125I-collagen I as ligand and heparin as activator. The standard curve is linear for a fibronectin range of 1.1-11 pmol (0.5-5.0 micrograms) and the coefficient of variation was less than 10...

  1. LIQUID SOAP CHARACTERISTIC WITH THE ADDITION OF FISH BONE COLLAGEN

    Directory of Open Access Journals (Sweden)

    Nauli A.P.

    2018-04-01

    Full Text Available Doublewhip Threadfin Bream (Nemipterus nematophorus fish is one of the low-cost economical sea fish that can be utilized which is expected to increase its selling value. The utilization of Doublewhip threadfin bream fish can be done with the waste management of the bones in order to have a selling value. Based on the research, other than its skin, bone is also one of the collagen producers in the body of a fish that can be used to increase the amount of collagen in the human body and slowing the aging process caused by damage skin cells that exposed to free radical. Fish bones are also an alternative to the mammals bones such as cows and pigs as collagen production materials that have been damaged by certain diseases. The method used in this research was laboratory experimental using Completely Randomized Design (RAL design. This research aims to analyze the characteristics of fish bone collagen that is applied to the liquid soap, which is done by physic and high. Based on the result of the test, the stability of foam is 84.90%; viscosity 922.83; cPs; pH 10.77 and free alkali 0.031% which meets the requirements of liquid quality based on SNI 06-4085-1996 so it is safe to apply on human skin.

  2. Collagen-lactoferrin fibrillar coatings enhance osteoblast proliferation and differentiation

    Czech Academy of Sciences Publication Activity Database

    Vandrovcová, Marta; Douglas, T.E.L.; Heinemann, S.; Scharnweber, D.; Dubruel, P.; Bačáková, Lucie

    2015-01-01

    Roč. 103, č. 2 (2015), s. 525-533 ISSN 1549-3296 R&D Projects: GA ČR(CZ) GBP108/12/G108 Institutional support: RVO:67985823 Keywords : lactoferin * collagen * bone cells Subject RIV: EI - Biotechnology ; Bionics Impact factor: 3.263, year: 2015

  3. Lysyl oxidases regulate fibrillar collagen remodelling in idiopathic pulmonary fibrosis

    NARCIS (Netherlands)

    Tjin, Gavin; White, Eric S; Faiz, Alen; Sicard, Delphine; Tschumperlin, Daniel J; Mahar, Annabelle; Kable, Eleanor P W; Burgess, Janette K

    2017-01-01

    Idiopathic pulmonary fibrosis (IPF) is a progressive scarring disease of the lung with feweffective therapeutic options. Structural remodelling of the extracellular matrix [i.e. collagen cross-linkingmediated by the lysyl oxidase (LO) family of enzymes (LOX, LOXL1-4)] might contribute to disease

  4. Clinical radiodiagnosis of collagen diseases. Klinicheskaya rentgenodiagnostika kollagenozov

    Energy Technology Data Exchange (ETDEWEB)

    Spasskaya, P A; Bartusevichene, A S

    1988-01-01

    General information about collagen diseases, short history of their theory development are presented; classification is discussed. Pathomorphology of connective tissue and vessels in these diseases is described. Clinicoroentgenologic diagnosis of internal organ and locomotor system injuries in systemic lupus erythemotosus, in sclerodermia systematica, in dermatomyositis in combination with morphological and clinicolabaratory data is analysed in detail. 166 refs.; 85 figs.

  5. Nanorod mediated collagen scaffolds as extra cellular matrix mimics

    International Nuclear Information System (INIS)

    Vedhanayagam, Mohan; Nair, Balachandran Unni; Sreeram, Kalarical Janardhanan; Mohan, Ranganathan

    2015-01-01

    Creating collagen scaffolds that mimic extracellular matrices without using toxic exogenous materials remains a big challenge. A new strategy to create scaffolds through end-to-end crosslinking through functionalized nanorods leading to well-designed architecture is presented here. Self-assembled scaffolds with a denaturation temperature of 110 °C, porosity of 70%, pore size of 0.32 μm and Young’s modulus of 231 MPa were developed largely driven by imine bonding between 3-mercapto-1-propanal (MPA) functionalized ZnO nanorods and collagen. The mechanical properties obtained were much higher than that of native collagen, collagen—MPA, collagen—3-mercapto-1-propanol (3MPOH) or collagen- 3-MPOH-ZnO, clearly bringing out the relevance of nanorod mediated assembly of fibrous networks. This new strategy has led to scaffolds with mechanical properties much higher than earlier reports and can provide support for cell growth and facilitation of cell attachment. (paper)

  6. A biocomposite of collagen nanofibers and nanohydroxyapatite for bone regeneration

    NARCIS (Netherlands)

    Ribeiro, N.; Sousa, S.R.; van Blitterswijk, Clemens; Moroni, Lorenzo; Monteiro, F.J.

    2014-01-01

    This work aims to design a synthetic construct that mimics the natural bone extracellular matrix through innovative approaches based on simultaneous type I collagen electrospinning and nanophased hydroxyapatite (nanoHA) electrospraying using non-denaturating conditions and non-toxic reagents. The

  7. Comparison of collagen profile and tenderness of muscles from ...

    African Journals Online (AJOL)

    2014-11-28

    Nov 28, 2014 ... Eight heifers (540 days old) and eight single-calf cows (836 days old), which were ... collagen is soluble and has a high proportion of reducible heat- ...... Have we under-estimated the impact of pre-slaughter stress on meat.

  8. Effect of vitamin C on collagen biosynthesis and degree of ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-06-17

    Jun 17, 2008 ... increase in the synthesis of collagen with no increase in the rate of synthesis of other proteins. .... The former compose rather a larger percentage of total .... nn. − δ is the birefringence given by the difference in the refractive ...

  9. Type I collagen from bullfrog ( Rana catesbeiana ) fallopian tube ...

    African Journals Online (AJOL)

    Rana catesbeiana) with a yield of 16.4%, on a dry weight basis. Sodium dodecyl sulphate polyacylamide-gel electrophoresis (SDS-PAGE) showed that the PSC contained two alpha components (α1 and α2) and was classified as type I collagen ...

  10. Cartilage turnover reflected by metabolic processing of type II collagen

    DEFF Research Database (Denmark)

    Gudmann, Karoline Natasja Stæhr; Wang, Jianxia; Hoielt, Sabine

    2014-01-01

    The aim of this study was to enable measurement of cartilage formation by a novel biomarker of type II collagen formation. The competitive enzyme-linked immunosorbent assay (ELISA) Pro-C2 was developed and characterized for assessment of the beta splice variant of type II procollagen (PIIBNP). Th...

  11. A 48 kDa collagen-binding phosphoprotein isolated from bovine aortic endothelial cells interacts with the collagenous domain, but not the globular domain, of collagen type IV.

    OpenAIRE

    Yannariello-Brown, J; Madri, J A

    1990-01-01

    We have identified collagen-binding proteins in detergent extracts of metabolically labelled bovine aortic endothelial cells (BAEC) by collagen type IV-Sepharose affinity chromatography. The major collagen type IV-binding protein identified by SDS/PAGE had a molecular mass of 48 kDa, which we term the 'collagen-binding 48 kDa protein' (CB48). The pI of CB48 was 8.0-8.3 in a two-dimensional gel system, running non-equilibrium pH gel electrophoresis in the first dimension and SDS/PAGE in the se...

  12. Cobalt(III) complex

    Indian Academy of Sciences (India)

    Administrator

    e, 40 µM complex, 10 hrs after dissolution, f, 40 µM complex, after irradiation dose 15 Gy. and H-atoms result in reduction of Co(III) to Co. (II). 6. It is interesting to see in complex containing multiple ligands what is the fate of electron adduct species formed by electron addition. Reduction to. Co(II) and intramolecular transfer ...

  13. Calculus III essentials

    CERN Document Server

    REA, Editors of

    2012-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Calculus III includes vector analysis, real valued functions, partial differentiation, multiple integrations, vector fields, and infinite series.

  14. Functional study on two artificial liver bioreactors with collagen gel

    Directory of Open Access Journals (Sweden)

    XU Bing

    2014-10-01

    Full Text Available ObjectiveTo improve the hollow fiber bioreactor of artificial liver. MethodsRat hepatocytes mixed with collagen solution were injected into the external cavity of a hollow fiber reactor to construct a bioreactor of hepatocytes suspended in collagen gel (group Ⅰ. Other rat hepatocytes suspended in solution were injected into the external cavity of a hollow fiber reactor with a layer of collagen on the wall of the external cavity to construct a bioreactor of collagen layer and hepatocytes (group Ⅱ. For each group, the culture solution circulated through the internal cavity of the hollow fiber bioreactor; the bioreactor was put in a culture box for 9 d, and the culture solution in the internal cavity was exchanged for new one every 24 h; the concentrations of albumin (Alb, urea, and lactate dehydrogenase (LDH in the culture solution samples were measured to examine the hepatocyte function of the bioreactor. Statistical analysis was performed using SPSS 130. Continuous data were expressed as mean±SD, and comparison between groups was made by paired t test. ResultsFor groups Ⅰ and Ⅱ, Alb levels reached peak values on day 3 of culture (1.41±0.08 g/L and 0.65±0.05 g/L; from day 3 to 9, group I had a significantly higher Alb level than group Ⅱ (t>7.572, P<0.01. For groups Ⅰ and Ⅱ, urea levels reached peak values on days 3 and 5 of culture (1.73±0.14 mmol/L and 1.56±0.18 mmol/L; from days 5 to 9, group I had a significantly higher urea level than group Ⅱ (t>8.418, P<0.01. For groups Ⅰ and Ⅱ, LDH levels reached peak values on day 9 of culture (32.03±9.13 U/L and 70.17±25.28 U/L; from days 1 to 9, group I had a significantly lower LDH level than group Ⅱ(t>5.633, P<0.01. Therefore, the bioreactor of hepatocytes suspended in collagen gel (group Ⅰ showed a better hepatocyte function and less hepatic enzyme leakage compared with the bioreactor of collagen layer and hepatocytes (group Ⅱ. Conclusion

  15. Structure to function: Spider silk and human collagen

    Science.gov (United States)

    Rabotyagova, Olena S.

    Nature has the ability to assemble a variety of simple molecules into complex functional structures with diverse properties. Collagens, silks and muscles fibers are some examples of fibrous proteins with self-assembling properties. One of the great challenges facing Science is to mimic these designs in Nature to find a way to construct molecules that are capable of organizing into functional supra-structures by self-assembly. In order to do so, a construction kit consisting of molecular building blocks along with a complete understanding on how to form functional materials is required. In this current research, the focus is on spider silk and collagen as fibrous protein-based biopolymers that can shed light on how to generate nanostructures through the complex process of self-assembly. Spider silk in fiber form offers a unique combination of high elasticity, toughness, and mechanical strength, along with biological compatibility and biodegrability. Spider silk is an example of a natural block copolymer, in which hydrophobic and hydrophilic blocks are linked together generating polymers that organize into functional materials with extraordinary properties. Since silks resemble synthetic block copolymer systems, we adopted the principles of block copolymer design from the synthetic polymer literature to build block copolymers based on spider silk sequences. Moreover, we consider spider silk to be an important model with which to study the relationships between structure and properties in our system. Thus, the first part of this work was dedicated to a novel family of spider silk block copolymers, where we generated a new family of functional spider silk-like block copolymers through recombinant DNA technology. To provide fundamental insight into relationships between peptide primary sequence, block composition, and block length and observed morphological and structural features, we used these bioengineered spider silk block copolymers to study secondary structure

  16. Disintegration of collagen fibrils by Glucono-δ-lactone: An implied lead for disintegration of fibrosis.

    Science.gov (United States)

    Jayamani, Jayaraman; Ravikanth Reddy, R; Madhan, Balaraman; Shanmugam, Ganesh

    2018-02-01

    Excess accumulation of collagen (fibrosis) undergoes self-aggregation, which leads to fibrillar collagen, on the extracellular matrix is the hallmark of a number of diseases such as keloids, hypertrophic scars, and systemic scleroderma. Direct inhibition or disintegration of collagen fibrils by small molecules offer a therapeutic approach to prevent or treat the diseases related to fibrosis. Herein, the anti-fibrotic property of Glucono-δ-lactone (GdL), known as acidifier, on the fibrillation and its disintegration of collagen was investigated. As collagen fibrillation is pH dependent, the pH modulation property of GdL is attractive to inhibit self-association of collagen. Optical density and microscopic data indicate that GdL elicits concentration-dependent fibril inhibition and also disintegrates pre-formed collagen fibrils. The simultaneous pH analysis showed that the modulation(lowering) of pH by GdL is the primary cause for its anti-fibrotic activity. The intact triple helical structure of collagen upon treatment of GdL suggests that collagen fibril disintegration can be achieved without affecting the native structure of collagen which is essential for any anti-fibrotic agents. Saturation transfer difference (STD) NMR result reveals that GdL is in proximity to collagen. The present results thus suggest that GdL provides a lead to design novel anti-fibrotic agents for the pathologies related to collagen deposition. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Strategies for Directing the Structure and Function of 3D Collagen Biomaterials across Length Scales

    Science.gov (United States)

    Walters, Brandan D.; Stegemann, Jan P.

    2013-01-01

    Collagen type I is a widely used natural biomaterial that has found utility in a variety of biological and medical applications. Its well characterized structure and role as an extracellular matrix protein make it a highly relevant material for controlling cell function and mimicking tissue properties. Collagen type I is abundant in a number of tissues, and can be isolated as a purified protein. This review focuses on hydrogel biomaterials made by reconstituting collagen type I from a solubilized form, with an emphasis on in vitro studies in which collagen structure can be controlled. The hierarchical structure of collagen from the nanoscale to the macroscale is described, with an emphasis on how structure is related to function across scales. Methods of reconstituting collagen into hydrogel materials are presented, including molding of macroscopic constructs, creation of microscale modules, and electrospinning of nanoscale fibers. The modification of collagen biomaterials to achieve desired structures and functions is also addressed, with particular emphasis on mechanical control of collagen structure, creation of collagen composite materials, and crosslinking of collagenous matrices. Biomaterials scientists have made remarkable progress in rationally designing collagen-based biomaterials and in applying them to both the study of biology and for therapeutic benefit. This broad review illustrates recent examples of techniques used to control collagen structure, and to thereby direct its biological and mechanical functions. PMID:24012608

  18. Accumulation of advanced glycation end products decreases collagen turnover by bovine chondrocytes

    NARCIS (Netherlands)

    Groot, J. de; Verzijl, N.; Budde, M.; Bijlsma, J.W.J.; Lafeber, F.P.J.G.; TeKoppele, J.M.

    2001-01-01

    The integrity of the collagen network is essential for articular cartilage to fulfill its function in load support and distribution. Damage to the collagen network is one of the first characteristics of osteoarthritis. Since extensive collagen damage is considered irreversible, it is crucial that

  19. RELATIONS BETWEEN INVITRO CYTOTOXICITY AND CROSS-LINKED DERMAL SHEEP COLLAGENS

    NARCIS (Netherlands)

    VANLUYN, MJA; VANWACHEM, PB; DAMINK, LO; DIJKSTRA, PJ; FEIJEN, J; NIEUWENHUIS, P

    Collagen-based biomaterials have found various applications in the biomedical field. However, collagen-based biomaterials may induce cytotoxic effects. This study evaluated possible cytotoxic effects of (crosslinked) dermal sheep collagen (DSC) using a 7-d-methylcellulose cell culture with human

  20. Training-induced changes in peritendinous type I collagen turnover determined by microdialysis in humans

    DEFF Research Database (Denmark)

    Langberg, Henning; Rosendal, L; Kjaer, M

    2001-01-01

    1. Acute exercise is found to increase collagen type I formation locally in peritendinous connective tissue of the Achilles' tendon in humans, as determined from changes in interstitial concentrations of collagen propeptide (PICP) and a collagen degradation product (ICTP) by the use of microdialy...

  1. Automated quantification of aligned collagen for human breast carcinoma prognosis

    Directory of Open Access Journals (Sweden)

    Jeremy S Bredfeldt

    2014-01-01

    Full Text Available Background: Mortality in cancer patients is directly attributable to the ability of cancer cells to metastasize to distant sites from the primary tumor. This migration of tumor cells begins with a remodeling of the local tumor microenvironment, including changes to the extracellular matrix and the recruitment of stromal cells, both of which facilitate invasion of tumor cells into the bloodstream. In breast cancer, it has been proposed that the alignment of collagen fibers surrounding tumor epithelial cells can serve as a quantitative image-based biomarker for survival of invasive ductal carcinoma patients. Specific types of collagen alignment have been identified for their prognostic value and now these tumor associated collagen signatures (TACS are central to several clinical specimen imaging trials. Here, we implement the semi-automated acquisition and analysis of this TACS candidate biomarker and demonstrate a protocol that will allow consistent scoring to be performed throughout large patient cohorts. Methods: Using large field of view high resolution microscopy techniques, image processing and supervised learning methods, we are able to quantify and score features of collagen fiber alignment with respect to adjacent tumor-stromal boundaries. Results: Our semi-automated technique produced scores that have statistically significant correlation with scores generated by a panel of three human observers. In addition, our system generated classification scores that accurately predicted survival in a cohort of 196 breast cancer patients. Feature rank analysis reveals that TACS positive fibers are more well-aligned with each other, are of generally lower density, and terminate within or near groups of epithelial cells at larger angles of interaction. Conclusion: These results demonstrate the utility of a supervised learning protocol for streamlining the analysis of collagen alignment with respect to tumor stromal boundaries.

  2. Agar/collagen membrane as skin dressing for wounds

    Energy Technology Data Exchange (ETDEWEB)

    Bao Lei; Yang Wei; Mao Xuan; Mou Shansong; Tang Shunqing [Biomedical Engineering Institute, Jinan University, Guangzhou (China)], E-mail: tshunqt@jnu.edu.cn, E-mail: tmuss@jnu.edu.cn

    2008-12-15

    Agar, a highly hydrophilic polymer, has a special gel property and favorable biocompatibility, but moderate intension strength in an aqueous condition and a low degradation rate. In order to tailor both properties of mechanical intension and degradation, type I collagen was composited with agar in a certain ratio by drying at 50 {sup 0}C or by a freeze-dry process. Glutaraldehyde was chosen as a crosslinking agent, and the most favorable condition for crosslinking was that the weight ratio of agar to glutaraldehyde was 66.7 and the pH value about 5. Dynamic mechanical analysis results showed that the single agar membrane had a modulus value between 640 MPa and 1064 MPa, but it was between 340 MPa and 819 MPa after being composited with type I collagen. It was discovered under an optical microscope that the pores were interconnected in the composite scaffolds instead of the honeycomb-like pores in a single type I collagen scaffold or the laminated gaps in a single agar scaffold. The results of an acute toxicity test disclosed that the composites were not toxic to mice although the composites were crosslinked with a certain concentration of glutaraldehyde. The results of gross examinations showed that when the composite membranes or scaffolds were applied to a repair rabbit skin lesion, the composites had a good repair effect without infection, liquid exudation or visible scar in the lesion covered with them. But in the control group, the autologous skin showed necrosis and there were a lot of scar tissues in the lesion site. H and E staining results showed that the repair tissue was similar to the normal one and very few scaffolds or membranes were left without degradation after 2 or 3 weeks. In conclusion, it is proved that type I collagen increases the toughness of the agar membrane, and the agar/type I collagen composites are promising biomaterials as wound dressings for healing burns or ulcers.

  3. Agar/collagen membrane as skin dressing for wounds

    International Nuclear Information System (INIS)

    Bao Lei; Yang Wei; Mao Xuan; Mou Shansong; Tang Shunqing

    2008-01-01

    Agar, a highly hydrophilic polymer, has a special gel property and favorable biocompatibility, but moderate intension strength in an aqueous condition and a low degradation rate. In order to tailor both properties of mechanical intension and degradation, type I collagen was composited with agar in a certain ratio by drying at 50 0 C or by a freeze-dry process. Glutaraldehyde was chosen as a crosslinking agent, and the most favorable condition for crosslinking was that the weight ratio of agar to glutaraldehyde was 66.7 and the pH value about 5. Dynamic mechanical analysis results showed that the single agar membrane had a modulus value between 640 MPa and 1064 MPa, but it was between 340 MPa and 819 MPa after being composited with type I collagen. It was discovered under an optical microscope that the pores were interconnected in the composite scaffolds instead of the honeycomb-like pores in a single type I collagen scaffold or the laminated gaps in a single agar scaffold. The results of an acute toxicity test disclosed that the composites were not toxic to mice although the composites were crosslinked with a certain concentration of glutaraldehyde. The results of gross examinations showed that when the composite membranes or scaffolds were applied to a repair rabbit skin lesion, the composites had a good repair effect without infection, liquid exudation or visible scar in the lesion covered with them. But in the control group, the autologous skin showed necrosis and there were a lot of scar tissues in the lesion site. H and E staining results showed that the repair tissue was similar to the normal one and very few scaffolds or membranes were left without degradation after 2 or 3 weeks. In conclusion, it is proved that type I collagen increases the toughness of the agar membrane, and the agar/type I collagen composites are promising biomaterials as wound dressings for healing burns or ulcers.

  4. Nanomechanical mapping of hydrated rat tail tendon collagen I fibrils.

    Science.gov (United States)

    Baldwin, Samuel J; Quigley, Andrew S; Clegg, Charlotte; Kreplak, Laurent

    2014-10-21

    Collagen fibrils play an important role in the human body, providing tensile strength to connective tissues. These fibrils are characterized by a banding pattern with a D-period of 67 nm. The proposed origin of the D-period is the internal staggering of tropocollagen molecules within the fibril, leading to gap and overlap regions and a corresponding periodic density fluctuation. Using an atomic force microscope high-resolution modulus maps of collagen fibril segments, up to 80 μm in length, were acquired at indentation speeds around 10(5) nm/s. The maps revealed a periodic modulation corresponding to the D-period as well as previously undocumented micrometer scale fluctuations. Further analysis revealed a 4/5, gap/overlap, ratio in the measured modulus providing further support for the quarter-staggered model of collagen fibril axial structure. The modulus values obtained at indentation speeds around 10(5) nm/s are significantly larger than those previously reported. Probing the effect of indentation speed over four decades reveals two distinct logarithmic regimes of the measured modulus and point to the existence of a characteristic molecular relaxation time around 0.1 ms. Furthermore, collagen fibrils exposed to temperatures between 50 and 62°C and cooled back to room temperature show a sharp decrease in modulus and a sharp increase in fibril diameter. This is also associated with a disappearance of the D-period and the appearance of twisted subfibrils with a pitch in the micrometer range. Based on all these data and a similar behavior observed for cross-linked polymer networks below the glass transition temperature, we propose that collagen I fibrils may be in a glassy state while hydrated.

  5. Effects of collagen matrix and bioreactor cultivation on cartilage regeneration of a full-thickness critical-size knee joint cartilage defects with subchondral bone damage in a rabbit model.

    Directory of Open Access Journals (Sweden)

    Kuo-Hwa Wang

    Full Text Available Cartilage has limited self-repair ability. The purpose of this study was to investigate the effects of different species of collagen-engineered neocartilage for the treatment of critical-size defects in the articular joint in a rabbit model. Type II and I collagen obtained from rabbits and rats was mixed to form a scaffold. The type II/I collagen scaffold was then mixed with rabbit chondrocytes to biofabricate neocartilage constructs using a rotating cell culture system [three-dimensional (3D-bioreactor]. The rabbit chondrocytes were mixed with rabbit collagen scaffold and rat collagen scaffold to form neoRBT (neo-rabbit cartilage and neoRAT (neo-rat cartilage constructs, respectively. The neocartilage matrix constructs were implanted into surgically created defects in rabbit knee chondyles, and histological examinations were performed after 2 and 3 months. Cartilage-like lacunae formation surrounding the chondrocytes was noted in the cell cultures. After 3 months, both the neoRBT and neoRAT groups showed cartilage-like repair tissue covering the 5-mm circular, 4-mm-deep defects that were created in the rabbit condyle and filled with neocartilage plugs. Reparative chondrocytes were aligned as apparent clusters in both the neoRAT and neoRBT groups. Both neoRBT and neoRAT cartilage repair demonstrated integration with healthy adjacent tissue; however, more integration was obtained using the neoRAT cartilage. Our data indicate that different species of type II/I collagen matrix and 3D bioreactor cultivation can facilitate cartilage engineering in vitro for the repair of critical-size defect.

  6. Urotensin II contributes to collagen synthesis and up-regulates Egr-1 expression in cultured pulmonary arterial smooth muscle cells through the ERK1/2 pathway

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wei [Biomedical Engineering Institute, School of Control Science and Engineering, Shandong University, Jinan 250061 (China); Cai, Zhifeng; Liu, Mengmeng [Department of Pediatrics, Qilu Hospital, Shandong University, Jinan 250012 (China); Zhao, Cuifen, E-mail: zhaocuifen@sdu.edu.cn [Department of Pediatrics, Qilu Hospital, Shandong University, Jinan 250012 (China); Li, Dong [Research Room of Hypothermia Medicine, Qilu Hospital, Shandong University, Jinan 250012 (China); Lv, Chenguang; Wang, Yuping; Xu, Tengfei [Biomedical Engineering Institute, School of Control Science and Engineering, Shandong University, Jinan 250061 (China)

    2015-11-27

    Aim: The objective of this study was to investigate the effects of urotensin II (UII) treatment on the proliferation and collagen synthesis of cultured rat pulmonary arterial smooth muscle cells (PASMCs) and to explore whether these effects are mediated by mitogen-activated protein kinase (MAPK) signaling pathways and early growth response 1 (Egr-1). Methods: The proliferation of cultured PASMCs stimulated with different doses of UII was detected by BrdU incorporation. The mRNA expression levels of procollagen I (procol I), procollagen III (procol III), extracellular regulated protein kinase 1/2 (ERK1/2), stress-stimulated protein kinase (Sapk), p38 MAPK (p38), and Egr-1 mRNA in cultured PASMCs after treatment with UII, the UII-specific antagonist urantide, and the ERK1/2 inhibitor PD98059 were detected by real-time polymerase chain reaction (PCR), and the protein expression levels of procol I, procol III, phosphorylated (p)-ERK1/2, p-Sapk, p-p38, and Egr-1 were detected by Western blotting. Results: Treatment with UII increased the proliferation of cultured PASMCs in a dose-dependent manner (P < 0.05). However, treatment with urantide and PD98059 inhibited the promoting effect of UII on PASMC proliferation (P < 0.05). Real-time PCR analysis showed that UII up-regulated the expression of procol I, procol III, ERK1/2, Sapk, and Egr-1 mRNA (P < 0.05), but not p38 mRNA. However, the up-regulating effect of UII was inhibited by PD98059 and urantide. Western blotting analysis showed that UII increased the synthesis of collagen I, collagen III, p-ERK1/2, p-Sapk, and Egr-1, and these effects also were inhibited by PD98059 and urantide (P < 0.05). Conclusions: Egr-1 participates in the UII-mediated proliferation and collagen synthesis of cultured rat PASMCs via activation of the ERK1/2 signaling pathway.

  7. A biomimetic strategy to form calcium phosphate crystals on type I collagen substrate

    Energy Technology Data Exchange (ETDEWEB)

    Xu Zhang [Department of Restorative Dentistry, Faculty of Dentistry, National University of Singapore, 5 Lower Kent Ridge Road 119074, Singapore (Singapore); Neoh, Koon Gee [Department of Chemical and Biomolecular Engineering, National University of Singapore, Kent Ridge 119260, Singapore (Singapore); Kishen, Anil, E-mail: anil.kishen@utoronto.ca [Discipline of Endodontics, Faculty of Dentistry, University of Toronto, 124 Edward Street, Toronto, ON (Canada)

    2010-07-20

    Objective: The aim of this study is to induce mineralization of collagen by introducing phosphate groups onto type I collagen from eggshell membrane (ESM) by treating with sodium trimetaphosphate (STMP). This strategy is based on the hypothesis that phosphate groups introduced on collagen can mimic the nucleating role of phosphorylated non-collagenous proteins bound to collagen for inducing mineralization in natural hard tissue. Method: The collagen membrane was phosphorylated by treating it with a solution of STMP and saturated calcium hydroxide. The phosphorylated collagen was subsequently exposed to a mineralization solution and the pattern of mineralization on the surface of phosphorylated collagen substrate was analyzed. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), field emission electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and microhardness test were used to characterize the collagen substrate and the pattern of minerals formed on the collagen surface. Results: The FTIR and EDX results indicated that the phosphate groups were incorporated onto the collagen surface by treatment with STMP. During the mineralization process, the plate-like mineral, octacalcium phosphate (OCP), which was initially formed on the surface of ESM, was later transformed into needle-like hydroxyapatite (HAP) as indicated by the SEM, FESEM, EDX and XRD findings. The microhardness test displayed significant increase in the Knoop hardness number of the mineralized collagen. Conclusions: Phosphate groups can be introduced onto type I collagen surface by treating it with STMP and such phosphorylated collagen can induce the mineralization of type I collagen.

  8. Investigation of the influence of UV irradiation on collagen thin films by AFM imaging

    International Nuclear Information System (INIS)

    Stylianou, Andreas; Yova, Dido; Alexandratou, Eleni

    2014-01-01

    Collagen is the major fibrous extracellular matrix protein and due to its unique properties, it has been widely used as biomaterial, scaffold and cell-substrate. The aim of the paper was to use Atomic Force Microscopy (AFM) in order to investigate well-characterized collagen thin films after ultraviolet light (UV) irradiation. The films were also used as in vitro culturing substrates in order to investigate the UV-induced alterations to fibroblasts. A special attention was given in the alteration on collagen D-periodicity. For short irradiation times, spectroscopy (fluorescence/absorption) studies demonstrated that photodegradation took place and AFM imaging showed alterations in surface roughness. Also, it was highlighted that UV-irradiation had different effects when it was applied on collagen solution than on films. Concerning fibroblast culturing, it was shown that fibroblast behavior was affected after UV irradiation of both collagen solution and films. Furthermore, after a long irradiation time, collagen fibrils were deformed revealing that collagen fibrils are consisting of multiple shells and D-periodicity occurred on both outer and inner shells. The clarification of the effects of UV light on collagen and the induced modifications of cell behavior on UV-irradiated collagen-based surfaces will contribute to the better understanding of cell–matrix interactions in the nanoscale and will assist in the appropriate use of UV light for sterilizing and photo-cross-linking applications. - Highlights: • Collagen thin films were formed and exposed in UV irradiation. • Collagen thin films were formed from UV-irradiated collagen solution. • Nanocharacterization of collagen thin films by AFM • Fluorescence and absorption spectroscopy studies on collagen films • Investigation of fibroblast response on collagen films

  9. Investigation of the influence of UV irradiation on collagen thin films by AFM imaging

    Energy Technology Data Exchange (ETDEWEB)

    Stylianou, Andreas, E-mail: styliand@mail.ntua.gr; Yova, Dido; Alexandratou, Eleni

    2014-12-01

    Collagen is the major fibrous extracellular matrix protein and due to its unique properties, it has been widely used as biomaterial, scaffold and cell-substrate. The aim of the paper was to use Atomic Force Microscopy (AFM) in order to investigate well-characterized collagen thin films after ultraviolet light (UV) irradiation. The films were also used as in vitro culturing substrates in order to investigate the UV-induced alterations to fibroblasts. A special attention was given in the alteration on collagen D-periodicity. For short irradiation times, spectroscopy (fluorescence/absorption) studies demonstrated that photodegradation took place and AFM imaging showed alterations in surface roughness. Also, it was highlighted that UV-irradiation had different effects when it was applied on collagen solution than on films. Concerning fibroblast culturing, it was shown that fibroblast behavior was affected after UV irradiation of both collagen solution and films. Furthermore, after a long irradiation time, collagen fibrils were deformed revealing that collagen fibrils are consisting of multiple shells and D-periodicity occurred on both outer and inner shells. The clarification of the effects of UV light on collagen and the induced modifications of cell behavior on UV-irradiated collagen-based surfaces will contribute to the better understanding of cell–matrix interactions in the nanoscale and will assist in the appropriate use of UV light for sterilizing and photo-cross-linking applications. - Highlights: • Collagen thin films were formed and exposed in UV irradiation. • Collagen thin films were formed from UV-irradiated collagen solution. • Nanocharacterization of collagen thin films by AFM • Fluorescence and absorption spectroscopy studies on collagen films • Investigation of fibroblast response on collagen films.

  10. Diffusion of MMPs on the Surface of Collagen Fibrils: The Mobile Cell Surface – Collagen Substratum Interface

    Science.gov (United States)

    Collier, Ivan E.; Legant, Wesley; Marmer, Barry; Lubman, Olga; Saffarian, Saveez; Wakatsuki, Tetsuro; Elson, Elliot; Goldberg, Gregory I.

    2011-01-01

    Remodeling of the extracellular matrix catalyzed by MMPs is central to morphogenetic phenomena during development and wound healing as well as in numerous pathologic conditions such as fibrosis and cancer. We have previously demonstrated that secreted MMP-2 is tethered to the cell surface and activated by MT1-MMP/TIMP-2-dependent mechanism. The resulting cell-surface collagenolytic complex (MT1-MMP)2/TIMP-2/MMP-2 can initiate (MT1-MMP) and complete (MMP-2) degradation of an underlying collagen fibril. The following question remained: What is the mechanism of substrate recognition involving the two structures of relatively restricted mobility, the cell surface enzymatic complex and a collagen fibril embedded in the ECM? Here we demonstrate that all the components of the complex are capable of processive movement on a surface of the collagen fibril. The mechanism of MT1-MMP movement is a biased diffusion with the bias component dependent on the proteolysis of its substrate, not adenosine triphosphate (ATP) hydrolysis. It is similar to that of the MMP-1 Brownian ratchet we described earlier. In addition, both MMP-2 and MMP-9 as well as their respective complexes with TIMP-1 and -2 are capable of Brownian diffusion on the surface of native collagen fibrils without noticeable dissociation while the dimerization of MMP-9 renders the enzyme immobile. Most instructive is the finding that the inactivation of the enzymatic activity of MT1-MMP has a detectable negative effect on the cell force developed in miniaturized 3D tissue constructs. We propose that the collagenolytic complex (MT1-MMP)2/TIMP-2/MMP-2 represents a Mobile Cell Surface – Collagen Substratum Interface. The biological implications of MT1-MMP acting as a molecular ratchet tethered to the cell surface in complex with MMP-2 suggest a new mechanism for the role of spatially regulated peri-cellular proteolysis in cell-matrix interactions. PMID:21912660

  11. Diffusion of MMPs on the surface of collagen fibrils: the mobile cell surface-collagen substratum interface.

    Directory of Open Access Journals (Sweden)

    Ivan E Collier

    Full Text Available Remodeling of the extracellular matrix catalyzed by MMPs is central to morphogenetic phenomena during development and wound healing as well as in numerous pathologic conditions such as fibrosis and cancer. We have previously demonstrated that secreted MMP-2 is tethered to the cell surface and activated by MT1-MMP/TIMP-2-dependent mechanism. The resulting cell-surface collagenolytic complex (MT1-MMP(2/TIMP-2/MMP-2 can initiate (MT1-MMP and complete (MMP-2 degradation of an underlying collagen fibril. The following question remained: What is the mechanism of substrate recognition involving the two structures of relatively restricted mobility, the cell surface enzymatic complex and a collagen fibril embedded in the ECM? Here we demonstrate that all the components of the complex are capable of processive movement on a surface of the collagen fibril. The mechanism of MT1-MMP movement is a biased diffusion with the bias component dependent on the proteolysis of its substrate, not adenosine triphosphate (ATP hydrolysis. It is similar to that of the MMP-1 Brownian ratchet we described earlier. In addition, both MMP-2 and MMP-9 as well as their respective complexes with TIMP-1 and -2 are capable of Brownian diffusion on the surface of native collagen fibrils without noticeable dissociation while the dimerization of MMP-9 renders the enzyme immobile. Most instructive is the finding that the inactivation of the enzymatic activity of MT1-MMP has a detectable negative effect on the cell force developed in miniaturized 3D tissue constructs. We propose that the collagenolytic complex (MT1-MMP(2/TIMP-2/MMP-2 represents a Mobile Cell Surface-Collagen Substratum Interface. The biological implications of MT1-MMP acting as a molecular ratchet tethered to the cell surface in complex with MMP-2 suggest a new mechanism for the role of spatially regulated peri-cellular proteolysis in cell-matrix interactions.

  12. Measurement of the quadratic hyperpolarizability of the collagen triple helix and application to second harmonic imaging of natural and biomimetic collagenous tissues

    Science.gov (United States)

    Deniset-Besseau, A.; Strupler, M.; Duboisset, J.; De Sa Peixoto, P.; Benichou, E.; Fligny, C.; Tharaux, P.-L.; Mosser, G.; Brevet, P.-F.; Schanne-Klein, M.-C.

    2009-09-01

    Collagen is a major protein of the extracellular matrix that is characterized by triple helical domains. It plays a central role in the formation of fibrillar and microfibrillar networks, basement membranes, as well as other structures of the connective tissue. Remarkably, fibrillar collagen exhibits efficient Second Harmonic Generation (SHG) so that SHG microscopy proved to be a sensitive tool to probe the three-dimensional architecture of fibrillar collagen and to assess the progression of fibrotic pathologies. We obtained sensitive and reproducible measurements of the fibrosis extent, but we needed quantitative data at the molecular level to further process SHG images. We therefore performed Hyper- Rayleigh Scattering (HRS) experiments and measured a second order hyperpolarisability of 1.25 10-27 esu for rat-tail type I collagen. This value is surprisingly large considering that collagen presents no strong harmonophore in its aminoacid sequence. In order to get insight into the physical origin of this nonlinear process, we performed HRS measurements after denaturation of the collagen triple helix and for a collagen-like short model peptide [(Pro-Pro- Gly)10]3. It showed that the collagen large nonlinear response originates in the tight alignment of a large number of weakly efficient harmonophores, presumably the peptide bonds, resulting in a coherent amplification of the nonlinear signal along the triple helix. To illustrate this mechanism, we successfully recorded SHG images in collagenous biomimetic matrices.

  13. A urokinase receptor-associated protein with specific collagen binding properties

    DEFF Research Database (Denmark)

    Behrendt, N; Jensen, O N; Engelholm, L H

    2000-01-01

    membrane-bound lectin with hitherto unknown function. The human cDNA was cloned and sequenced. The protein, designated uPARAP, is a member of the macrophage mannose receptor protein family and contains a putative collagen-binding (fibronectin type II) domain in addition to 8 C-type carbohydrate recognition...... domains. It proved capable of binding strongly to a single type of collagen, collagen V. This collagen binding reaction at the exact site of plasminogen activation on the cell may lead to adhesive functions as well as a contribution to cellular degradation of collagen matrices....

  14. The anabolic effects of insulin on type II collagen synthesis of Swarm rat chondrosarcoma chondrocytes

    International Nuclear Information System (INIS)

    Bembenek, M.E.; Liberti, J.P.

    1984-01-01

    The anabolic effects of insulin on collagen production of freshly isolated Swarm rat chondrosarcoma chondrocytes were investigated. The specific radioactivity of newly synthesized collagen was not increased by insulin, indicating that the hormone has no effect on the specific radioactivity of the aminoacyl tRNA pool. Results of further studies obtained from collagen degradation experiments demonstrated that insulin did not alter the rate of [3H]collagen degradation. Together, these results clearly indicate that insulin stimulates collagen biosynthesis. Polyacrylamide gel analysis of the newly synthesized collagen of both control and insulin-stimulated cells revealed a large-molecular-weight component which migrated with authentic alpha 1(II) collagen and was collagenase-sensitive. Additional studies showed that, although insulin increased the processing and secretion of collagen, the hormone did not cause a shift in the distribution of the extracellular and intracellular collagen pools. Finally, results of studies conducted with the transcriptional inhibitor, actinomycin D, indicated that the anabolic effects of insulin on collagen and non-collagen proteins were mediated at a post-transcriptional site

  15. Preparation, Cell Compatibility and Degradability of Collagen-Modified Poly(lactic acid

    Directory of Open Access Journals (Sweden)

    Miaomiao Cui

    2015-01-01

    Full Text Available Poly(lactic acid (PLA was modified using collagen through a grafting method to improve its biocompatibility and degradability. The carboxylic group at the open end of PLA was transferred into the reactive acylchlorided group by a reaction with phosphorus pentachloride. Then, collagen-modified PLA (collagen-PLA was prepared by the reaction between the reactive acylchlorided group and amino/hydroxyl groups on collagen. Subsequently, the structure of collagen-PLA was confirmed by Fourier transform infrared spectroscopy, fluorescein isothiocyanate-labeled fluorescence spectroscopy, X-ray photoelectron spectroscopy, and DSC analyses. Finally, some properties of collagen-PLA, such as hydrophilicity, cell compatibility and degradability were characterized. Results showed that collagen had been grafted onto the PLA with 5% graft ratio. Water contact angle and water absorption behavior tests indicated that the hydrophilicity of collagen-PLA was significantly higher than that of PLA. The cell compatibility of collagen-PLA with mouse embryonic fibroblasts (3T3 was also significantly better than PLA in terms of cell morphology and cell proliferation, and the degradability of PLA was also improved after introducing collagen. Results suggested that collagen-PLA was a promising candidate for biomedical applications.

  16. A microscopic evaluation of collagen-bilirubin interactions: in vitro surface phenomenon.

    Science.gov (United States)

    Usharani, N; Jayakumar, G C; Rao, J R; Chandrasekaran, B; Nair, B U

    2014-02-01

    This study is carried out to understand the morphology variations of collagen I matrices influenced by bilirubin. The characteristics of bilirubin interaction with collagen ascertained using various techniques like XRD, CLSM, fluorescence, SEM and AFM. These techniques are used to understand the distribution, expression and colocalization patterns of collagen-bilirubin complexes. The present investigation mimic the in vivo mechanisms created during the disorder condition like jaundice. Fluorescence technique elucidates the crucial role played by bilirubin deposition and interaction during collagen organization. Influence of bilirubin during collagen fibrillogenesis and banding patterns are clearly visualize using SEM. As a result, collagen-bilirubin complex provides different reconstructed patterns because of the influence of bilirubin concentration. Selectivity, specificity and spatial organization of collagen-bilirubin are determined through AFM imaging. Consequently, it is observed that the morphology and quantity of the bilirubin binding to collagen varied by the concentrations and the adsorption rate in protein solutions. Microscopic studies of collagen-bilirubin interaction confirms that bilirubin influence the fibrillogenesis and alter the rate of collagen organization depending on the bilirubin concentration. This knowledge helps to develop a novel drug to inhibit the interface point of interaction between collagen and bilirubin. © 2013 The Authors Journal of Microscopy © 2013 Royal Microscopical Society.

  17. Diffusion and Binding of Laponite Clay Nanoparticles into Collagen Fibers for the Formation of Leather Matrix.

    Science.gov (United States)

    Shi, Jiabo; Wang, Chunhua; Ngai, To; Lin, Wei

    2018-06-13

    Understanding accessibility and interactions of clay nanoparticles with collagen fibers is an important fundamental issue for the conversion of collagen to leather matrix. In this study, we have investigated the diffusion and binding of Laponite into the collagen fiber network. Our results indicate that the diffusion behaviors of Laponite into the collagen exhibit the Langmuir adsorption, verifying its affinity for collagen. The introduction of Laponite leads to a shift in the isoelectric point of collagen from ∼6.8 to ∼4.5, indicating the ionic bonding between the positively charged amino groups of the collagen and negatively charged Laponite under the tanning conditions. Fluorescence microscopy, atomic force microscopy, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and wide-angle X-ray diffraction analyses reveal that Laponite nanoparticles can penetrate into collagen microstructure and evenly distributed onto collagen fibrils, not altering native D-periodic banding patterns of collagen fibrils. Attenuated total reflectance-Fourier transform infrared and Raman spectroscopy detections further demonstrate the presence of noncovalent interactions, namely, ionic and hydrogen bonding, between Laponite and collagen. These findings provide a theoretical basis for the use of Laponite as an emerging tanning agent in leather manufacture.

  18. A novel combined polyphenol-aldehyde crosslinking of collagen film-Applications in biomedical materials.

    Science.gov (United States)

    Liu, Ting; Shi, Lu; Gu, Zhipeng; Dan, Weihua; Dan, Nianhua

    2017-08-01

    Despite its crucial role in directing cell fate in healthy and diseased tissues, improvements in physical-chemical properties and biocompatibility of type-I collagen are still needed. In this report, we described combined and facile method to modify collagen. The collagen film was first modified by procyanidins solution, in which, then subjected to further crosslinked by dialdehyde alginate, resulting in collagen-procyanidins-dialdehyde alginate film. The properties of the crosslinked collagen films were investigated and the results were discussed. Results from differential scanning calorimetry and thermo gravimetric analysis suggested that the thermal stabilities of the collagen-procyanidins-dialdehyde alginate film were significantly improved. The mechanical properties of collagen-procyanidins-dialdehyde alginate film in terms of elongation at break and tensile strength increased approximately 2-fold and 3-fold, respectively compare to pure collagen film. In addition, the resistance to collagenase degradation of collagen-procyanidins-dialdehyde alginate film was remarkably promoted. The results from methyltetrazolium assay and confocal laser scanning microscopy showed that no cytotoxicity of collagen film was introduced by the combined crosslinking method. Thus, the novel combined by procyanidins-dialdehyde alginate crosslinking method shown in this study provided a non-toxic and efficient crosslinking method that improved various properties of collagen film, which has great potential applications in biomedical materials. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Amino acid composition in determination of collagen origin and assessment of physical factors effects.

    Science.gov (United States)

    Gauza-Włodarczyk, Marlena; Kubisz, Leszek; Włodarczyk, Dariusz

    2017-11-01

    The amino acid composition of collagen is a characteristic feature of this protein. Collagen, irrespective of its origin, contains 19 amino acids, including hydroxyproline which does not occur in other proteins. Its atypical amino acid composition is characterized by high content of proline and glycine, as well as the absence of cysteine. This paper shows the comparison of qualitative composition of amino acids of fish skin (FS) collagen, bovine Achilles tendon (BAT) collagen, and bone collagen. Results demonstrate that FS collagen as well as BAT collagen contains no cysteine and significantly different amount of hydroxyproline. In BAT collagen hydroxyproline content is 30% higher than hydroxyproline content of FS collagen. In bone collagen the amount of hydroxyproline is two times more than in FS collagen. Furthermore, it is shown that sensitivity to radiation of individual amino acids varies and depends on the absorbed dose of ionizing radiation. The changes observed in the amino acid composition become very intense for the doses of 500kGy and 1000kGy. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Protease inhibitors enhance extracellular collagen fibril deposition in human mesenchymal stem cells.

    Science.gov (United States)

    Han, Sejin; Li, Yuk Yin; Chan, Barbara Pui

    2015-10-15

    Collagen is a widely used naturally occurring biomaterial for scaffolding, whereas mesenchymal stem cells (MSCs) represent a promising cell source in tissue engineering and regenerative medicine. It is generally known that cells are able to remodel their environment by simultaneous degradation of the scaffolds and deposition of newly synthesized extracellular matrix. Nevertheless, the interactions between MSCs and collagen biomaterials are poorly known, and the strategies enhancing the extracellular matrix deposition are yet to be defined. In this study, we aim to investigate the fate of collagen when it is in contact with MSCs and hypothesize that protease inhibition will enhance their extracellular deposition of collagen fibrils. Specifically, human MSCs (hMSCs) were exposed to fluorescence-labeled collagen with and without intracellular or extracellular protease inhibitors (or both) before tracing the collagen at both intracellular and extracellular spaces. Collagen were internalized by hMSCs and degraded intracellularly in lysosomes. In the presence of protease inhibitors, both intracellular collagen fibril growth and extracellular deposition of collagen fibrils were enhanced. Moreover, protease inhibitors work synergistically with ascorbic acid, a well-known matrix deposition-enhancing reagent, in further enhancing collagen fibril deposition at the extracellular space. These findings provide a better understanding of the interactions between hMSCs and collagen biomaterials and suggest a method to manipulate matrix remodeling and deposition of hMSCs, contributing to better scaffolding for tissue engineering and regenerative medicine.

  1. Structure–mechanics relationships of collagen fibrils in the osteogenesis imperfecta mouse model

    Science.gov (United States)

    Andriotis, O. G.; Chang, S. W.; Vanleene, M.; Howarth, P. H.; Davies, D. E.; Shefelbine, S. J.; Buehler, M. J.; Thurner, P. J.

    2015-01-01

    The collagen molecule, which is the building block of collagen fibrils, is a triple helix of two α1(I) chains and one α2(I) chain. However, in the severe mouse model of osteogenesis imperfecta (OIM), deletion of the COL1A2 gene results in the substitution of the α2(I) chain by one α1(I) chain. As this substitution severely impairs the structure and mechanics of collagen-rich tissues at the tissue and organ level, the main aim of this study was to investigate how the structure and mechanics are altered in OIM collagen fibrils. Comparing results from atomic force microscopy imaging and cantilever-based nanoindentation on collagen fibrils from OIM and wild-type (WT) animals, we found a 33% lower indentation modulus in OIM when air-dried (bound water present) and an almost fivefold higher indentation modulus in OIM collagen fibrils when fully hydrated (bound and unbound water present) in phosphate-buffered saline solution (PBS) compared with WT collagen fibrils. These mechanical changes were accompanied by an impaired swelling upon hydration within PBS. Our experimental and atomistic simulation results show how the structure and mechanics are altered at the individual collagen fibril level as a result of collagen gene mutation in OIM. We envisage that the combination of experimental and modelling approaches could allow mechanical phenotyping at the collagen fibril level of virtually any alteration of collagen structure or chemistry. PMID:26468064

  2. Effect of supramolecular organization of a cartilaginous tissue on thermal stability of collagen II

    Science.gov (United States)

    Ignat'eva, N. Yu.; Averkiev, S. V.; Lunin, V. V.; Grokhovskaya, T. E.; Obrezkova, M. V.

    2006-08-01

    The thermal stability of collagen II in various cartilaginous tissues was studied. It was found that heating a tissue of nucleus pulposus results in collagen II melting within a temperature range of 60-70°C; an intact tissue of hyaline cartilage (of nasal septum and cartilage endplates) is a thermally stable system, where collagen II is not denatured completely up to 100°C. It was found that partial destruction of glycosaminoglycans in hyaline cartilage leads to an increase in the degree of denaturation of collagen II upon heating, although a significant fraction remains unchanged. It was shown that electrostatic interactions of proteoglycans and collagen only slightly affect the thermal stability of collagen II in the tissues. Evidently, proteoglycan aggregates play a key role: they create topological hindrances for moving polypeptide chains, thereby reducing the configurational entropy of collagen macromolecules in the state of a random coil.

  3. Complex Determinants in Specific Members of the Mannose Receptor Family Govern Collagen Endocytosis

    DEFF Research Database (Denmark)

    Jürgensen, Henrik J; Johansson, Kristina; Madsen, Daniel H

    2014-01-01

    Members of the well-conserved mannose receptor (MR) protein family have been functionally implicated in diverse biological and pathological processes. Importantly, a proposed common function is the internalization of collagen for intracellular degradation occurring during bone development, cancer...... invasion, and fibrosis protection. This functional relationship is suggested by a common endocytic capability and a candidate collagen-binding domain. Here we conducted a comparative investigation of each member's ability to facilitate intracellular collagen degradation. As expected, the family members u......PARAP/Endo180 and MR bound collagens in a purified system and internalized collagens for degradation in cellular settings. In contrast, the remaining family members, PLA2R and DEC-205, showed no collagen binding activity and were unable to mediate collagen internalization. To pinpoint the structural elements...

  4. Manipulation of in vitro collagen matrix architecture for scaffolds of improved physiological relevance

    Science.gov (United States)

    Hapach, Lauren A.; VanderBurgh, Jacob A.; Miller, Joseph P.; Reinhart-King, Cynthia A.

    2015-12-01

    Type I collagen is a versatile biomaterial that is widely used in medical applications due to its weak antigenicity, robust biocompatibility, and its ability to be modified for a wide array of applications. As such, collagen has become a major component of many tissue engineering scaffolds, drug delivery platforms, and substrates for in vitro cell culture. In these applications, collagen constructs are fabricated to recapitulate a diverse set of conditions. Collagen fibrils can be aligned during or post-fabrication, cross-linked via numerous techniques, polymerized to create various fibril sizes and densities, and copolymerized into a wide array of composite scaffolds. Here, we review approaches that have been used to tune collagen to better recapitulate physiological environments for use in tissue engineering applications and studies of basic cell behavior. We discuss techniques to control fibril alignment, methods for cross-linking collagen constructs to modulate stiffness, and composite collagen constructs to better mimic physiological extracellular matrix.

  5. Always cleave up your mess: targeting collagen degradation to treat tissue fibrosis

    Science.gov (United States)

    McKleroy, William; Lee, Ting-Hein

    2013-01-01

    Pulmonary fibrosis is a vexing clinical problem with no proven therapeutic options. In the normal lung there is continuous collagen synthesis and collagen degradation, and these two processes are precisely balanced to maintain normal tissue architecture. With lung injury there is an increase in the rate of both collagen production and collagen degradation. The increase in collagen degradation is critical in preventing the formation of permanent scar tissue each time the lung is exposed to injury. In pulmonary fibrosis, collagen degradation does not keep pace with collagen production, resulting in extracellular accumulation of fibrillar collagen. Collagen degradation occurs through both extracellular and intracellular pathways. The extracellular pathway involves cleavage of collagen fibrils by proteolytic enzyme including the metalloproteinases. The less-well-described intracellular pathway involves binding and uptake of collagen fragments by fibroblasts and macrophages for lysosomal degradation. The relationship between these two pathways and their relevance to the development of fibrosis is complex. Fibrosis in the lung, liver, and skin has been associated with an impaired degradative environment. Much of the current scientific effort in fibrosis is focused on understanding the pathways that regulate increased collagen production. However, recent reports suggest an important role for collagen turnover and degradation in regulating the severity of tissue fibrosis. The objective of this review is to evaluate the roles of the extracellular and intracellular collagen degradation pathways in the development of fibrosis and to examine whether pulmonary fibrosis can be viewed as a disease of impaired matrix degradation rather than a disease of increased matrix production. PMID:23564511

  6. Silymarin retards collagen accumulation in early and advanced biliary fibrosis secondary to complete bile duct obliteration in rats.

    Science.gov (United States)

    Boigk, G; Stroedter, L; Herbst, H; Waldschmidt, J; Riecken, E O; Schuppan, D

    1997-09-01

    Silymarin (SIL), a standardized plant extract containing about 60% polyphenole silibinin, is used as a hepatoprotective agent. Its antifibrotic potential in chronic liver diseases has not been explored. Therefore, we applied SIL to adult Wistar rats that were subjected to complete bile duct occlusion (BDO) by injection of sodium amidotrizoate (Ethibloc). This treatment induces progressive portal fibrosis without significant inflammation. Rats with sham-operation that received SIL at 50 mg/kg/d (n = 10) and rats with BDO alone (n = 20) served as controls, whereas groups of 20 animals were fed SIL at a dose of 25 and 50 mg/kg/d during weeks 1 through 6 or doses of 50 mg/kg/d during weeks 4 through 6 of BDO. Animals were sacrificed after 6 weeks for determination of blood chemistries, total and relative liver collagen (as hydroxyproline [HYP]), and the serum aminoterminal propeptide of procollagen type III (PIIINP). BDO in untreated rats caused an almost ninefold increase in total liver collagen (16.1 +/- 3.1 vs. 1.8 +/- 0.4 mg HYP, P liver tissue, it acted as a true antifibrotic agent. The single value of PIIINP at killing paralleled the antifibrotic activity of SIL with 11.6 +/- 3.8 and 9.9 +/- 3.7 vs. 15.3 +/- 5.2 microg/L in both high-dose groups (P fibrosis score in the groups that received SIL, clinical-chemical parameters were not different among all groups with BDO. We therefore conclude that 1) BDO with Ethibloc is a suitable model to test for pure antifibrotic drugs because it induces progressive rat secondary biliary fibrosis without major inflammation; 2) oral SIL can ameliorate hepatic collagen accumulation even in advanced (biliary) fibrosis; and 3) PIIINP appears to be a suitable serum marker to monitor the inhibition of hepatic fibrogenesis in this model of biliary fibrosis.

  7. Interleukin-1 inhibits the synthesis of collagen by fibroblasts.

    Science.gov (United States)

    Bhatnagar, R; Penfornis, H; Mauviel, A; Loyau, G; Saklatvala, J; Pujol, J P

    1986-10-01

    Human dermal fibroblasts, exposed to human or porcine Interleukin-1, responded by an inhibition of collagen synthesis in a dose dependent manner. Incubation with Il-1 for more than 8 h was required to see an appreciable effect. The phenomenon was not dependent on the presence of serum in the culture medium. Since a stimulation of prostaglandin E2 secretion was also observed in presence of Il-1, we investigated the eventual role of arachidonic acid metabolites in the phenomenon. Inhibitors interfering with arachidonate metabolism, namely indomethacin, acetyl salicylic acid, BW 755 C and NDGA had no influence on the inhibition of collagen synthesis caused by Il-1. These data suggest that both cyclooxygenase and lipoxygenase derived metabolites of arachidonic acid are unlikely to play a role in the mechanism.

  8. Monitoring single protease activities on triple-helical collagen molecules

    Science.gov (United States)

    Harzar, Raj; Froberg, James; Srivastava, D. K.; Choi, Yongki

    Matrix metalloproteinases (MMPs), a particular family of proteases, play a pivotal role in degrading the extracellular matrix (ECM). It has been known for more than 40 years that MMPs are closely involved in multiple human cancers during cell growth, invasion, and metastasis. However, the mechanisms of MMP activity are far from being understood. Here, we monitored enzymatic processing of MMPs with two complementary approaches, atomic force microscopy and nanocircuits measurements. AFM measurements demonstrated that incubation of collagen monomers with MMPs resulted in a single position cleavage, producing 3/4 and 1/4 collagen fragments. From electronic monitoring of single MMP nanocircuit measurements, we were able to capture a single cleavage event with a rate of 0.012 Hz, which were in good agreement with fluorescence assay measurements. This work was supported financially by the NIGMS/NIH (P30GM103332-02) and ND NASA EPSCoR RID Grant.

  9. Collagen expression in fibroblasts with a novel LMNA mutation

    International Nuclear Information System (INIS)

    Nguyen, Desiree; Leistritz, Dru F.; Turner, Lesley; MacGregor, David; Ohson, Kamal; Dancey, Paul; Martin, George M.; Oshima, Junko

    2007-01-01

    Laminopathies are a group of genetic disorders caused by LMNA mutations; they include muscular dystrophies, lipodystrophies, and progeroid syndromes. We identified a novel heterozygous LMNA mutation, L59R, in a patient with the general appearance of mandibuloacral dysplasia and progeroid features. Examination of the nuclei of dermal fibroblasts revealed the irregular morphology characteristic of LMNA mutant cells. The nuclear morphological abnormalities of LMNA mutant lymphoblastoid cell lines were less prominent compared to those of primary fibroblasts. Since it has been reported that progeroid features are associated with increased extracellular matrix in dermal tissues, we compared a subset of these components in fibroblast cultures from LMNA mutants with those of control fibroblasts. There was no evidence of intracellular accumulation or altered mobility of collagen chains, or altered conversion of procollagen to collagen, suggesting that skin fibroblast-mediated matrix production may not play a significant role in the pathogenesis of this particular laminopathy

  10. [Diagnostic values of serum type III procollagen N-terminal peptide in type IV gastric cancer].

    Science.gov (United States)

    Akazawa, S; Fujiki, T; Kanda, Y; Kumai, R; Yoshida, S

    1985-04-01

    Since increased synthesis of collagen has been demonstrated in tissue of type IV gastric cancer, we attempted to distinguish type IV gastric cancer from other cancers by measuring serum levels of type III procollagen N-terminal peptide (type III-N-peptide). Mean serum levels in type IV gastric cancer patients without metastasis were found to be elevated above normal values and developed a tendency to be higher than those in types I, II and III gastric cancer patients without metastasis. Highly positive ratios were found in patients with liver diseases including hepatoma and colon cancer, biliary tract cancer, and esophageal cancer patients with liver, lung or bone metastasis, but only 2 out of 14 of these cancer patients without such metastasis showed positive serum levels of type III-N-peptide. Positive cases in patients with type IV gastric cancer were obtained not only in the group with clinical stage IV but also in the groups with clinical stages II and III. In addition, high serum levels of type III-N-peptide in patients with type IV gastric cancer were seen not only in the cases with liver, lung or bone metastasis but also in cases with disseminated peritoneal metastasis alone. These results suggest that if the serum level of type III-N-peptide is elevated above normal values, type IV gastric cancer should be suspected after ruling out liver diseases, myelofibrosis and liver, lung or bone metastasis.

  11. Strain-induced collagen organization at the micro-level in fibrin-based engineered tissue constructs

    NARCIS (Netherlands)

    Jonge, de N.; Kanters, F.M.W.; Baaijens, F.P.T.; Bouten, C.V.C.

    2013-01-01

    Full understanding of strain-induced collagen organization in complex tissue geometries to create tissues with predefined collagen architecture has not been achieved. This is mainly due to our limited knowledge of collagen remodeling in developing tissues. Here we investigate strain-induced collagen

  12. Neutrophilic dermatoses in a patient with collagenous colitis

    OpenAIRE

    Didac Barco; Maria A. Barnadas; Esther Roé; Francisco J. Sancho; Elena Ricart; Agustín Alomar

    2010-01-01

    We report the case of a 75-year old woman with collagenous colitis who presented with erythematous and edematous plaques on the periorbital and eyelid regions, accompanied by oral ulcers. Histopathology showed a dermal neutrophilic infiltrate plus mild septal and lobular panniculitis with lymphocytes, neutrophils and eosinophils. Five years earlier she had presented a flare of papules and vesicles on the trunk, together with oral ulcers; a skin biopsy revealed a neutrophilic dermal infiltrate...

  13. Nanoindentation characterisation of poly(DL-lactide)/collagen nanocomposites

    Czech Academy of Sciences Publication Activity Database

    Suchý, Tomáš; Rýglová, Šárka; Sucharda, Zbyněk; Balík, Karel; Šepitka, J.; Lukeš, J.

    2012-01-01

    Roč. 15, S1 (2012), s. 89-90 ISSN 1025-5842. [Congress of the Société de Biomécanique /37./. Toulouse, 16.10.2012-19.10.2012] R&D Projects: GA ČR(CZ) GA106/09/1000 Institutional research plan: CEZ:AV0Z30460519 Keywords : collagen * poly(DL-lactide) * nanofibres Subject RIV: BO - Biophysics Impact factor: 1.393, year: 2012

  14. Toward single cell traction microscopy within 3D collagen matrices

    International Nuclear Information System (INIS)

    Hall, Matthew S.; Long, Rong; Feng, Xinzeng; Huang, YuLing; Hui, Chung-Yuen; Wu, Mingming

    2013-01-01

    Mechanical interaction between the cell and its extracellular matrix (ECM) regulates cellular behaviors, including proliferation, differentiation, adhesion, and migration. Cells require the three-dimensional (3D) architectural support of the ECM to perform physiologically realistic functions. However, current understanding of cell–ECM and cell–cell mechanical interactions is largely derived from 2D cell traction force microscopy, in which cells are cultured on a flat substrate. 3D cell traction microscopy is emerging for mapping traction fields of single animal cells embedded in either synthetic or natively derived fibrous gels. We discuss here the development of 3D cell traction microscopy, its current limitations, and perspectives on the future of this technology. Emphasis is placed on strategies for applying 3D cell traction microscopy to individual tumor cell migration within collagen gels. - Highlights: • Review of the current state of the art in 3D cell traction force microscopy. • Bulk and micro-characterization of remodelable fibrous collagen gels. • Strategies for performing 3D cell traction microscopy within collagen gels

  15. Susceptibility of Calcium-Deficient Hydroxapatite Collagen Composite to Irradiation

    International Nuclear Information System (INIS)

    Ohta, M.; Yasuda, M.; Okamura, H.

    2001-01-01

    The ESR spectrum of calcium-deficient hydroxyapatite (DAp) has the peaks assigned to the hyperfine structure of dangling H + (hyperfine coupling constant = 50.8 mT, I = 1/2) due to the HPO 2- 4 ion which captured the hole released by X ray irradiation. This ESR peak intensity in DAp with collagen (c-DAp) decreased in an increase in the amount of collagen added into Ca(H 2 PO 4 ) 2 .H 2 O (MCP) electrolytic solution, because dangling H + of HPO 2- 4 binds to the carboxyl group of collagen due to the hydrogen bond. The ESR signal intensities at near g=2 in DAp, c-DAp, and stoichiometric hydroxyapatite (HAp) after X ray irradiation, were proportional to the absorbed dose in the range from 6 to 380 Gy. These ESR signal intensities decreased when the X ray-irradiated DAp, c-DAp, and HAp was suspended in the simulated body fluid. This fact suggests that the surface layer contained high density of ESR active species in DAp, c-DAp, and HAp dissolved in the simulated body fluid. Therefore, with the dosemeter utilising such biomaterials as tooth and bone, sufficient care must be paid to the effect of body fluid. (author)

  16. Collagenous microstructure of the glenoid labrum and biceps anchor.

    Science.gov (United States)

    Hill, A M; Hoerning, E J; Brook, K; Smith, C D; Moss, J; Ryder, T; Wallace, A L; Bull, A M J

    2008-06-01

    The glenoid labrum is a significant passive stabilizer of the shoulder joint. However, its microstructural form remains largely unappreciated, particularly in the context of its variety of functions. The focus of labral microscopy has often been histology and, as such, there is very little appreciation of collagen composition and arrangement of the labrum, and hence the micromechanics of the structure. On transmission electron microscopy, significant differences in diameter, area and perimeter were noted in the two gross histological groups of collagen fibril visualized; this suggests a heterogeneous collagenous composition with potentially distinct mechanical function. Scanning electron microscopy demonstrated three distinct zones of interest: a superficial mesh, a dense circumferential braided core potentially able to accommodate hoop stresses, and a loosely packed peri-core zone. Confocal microscopy revealed an articular surface fine fibrillar mesh potentially able to reduce surface friction, bundles of circumferential encapsulated fibres in the bulk of the tissue, and bone anchoring fibres at the osseous interface. Varying microstructure throughout the depth of the labrum suggests a role in accommodating different types of loading. An understanding of the labral microstructure can lead to development of hypotheses based upon an appreciation of this component of material property. This may aid an educated approach to surgical timing and repair.

  17. Microablation of collagen-based substrates for soft tissue engineering

    International Nuclear Information System (INIS)

    Kumar, Vivek A; Caves, Jeffrey M; Naik, Nisarga; Haller, Carolyn A; Chaikof, Elliot L; Martinez, Adam W

    2014-01-01

    Noting the abundance and importance of collagen as a biomaterial, we have developed a facile method for the production of a dense fibrillar extracellular matrix mimicking collagen–elastin hybrids with tunable mechanical properties. Through the use of excimer-laser technology, we have optimized conditions for the ablation of collagen lamellae without denaturation of protein, maintenance of fibrillar ultrastructure and preservation of native D-periodicity. Strengths of collagen–elastin hybrids ranged from 0.6 to 13 MPa, elongation at break from 9 to 70% and stiffness from 2.9 to 94 MPa, allowing for the design of a wide variety of tissue specific scaffolds. Further, large (centimeter scale) lamellae can be fabricated and embedded with recombinant elastin to generate collagen–elastin hybrids. Exposed collagen in hybrids act as cell adhesive sites for rat mesenchymal stem cells that conform to ablate waveforms. The ability to modulate these features allows for the generation of a class of biopolymers that can architecturally and physiologically replicate native tissue. (communication)

  18. Artificially modified collagen fibril orientation affects leather tear strength.

    Science.gov (United States)

    Kelly, Susyn J; Wells, Hannah C; Sizeland, Katie H; Kirby, Nigel; Edmonds, Richard L; Ryan, Tim; Hawley, Adrian; Mudie, Stephen; Haverkamp, Richard G

    2018-07-01

    Ovine leather has around half the tear strength of bovine leather and is therefore not suitable for high-value applications such as shoes. Tear strength has been correlated with the natural collagen fibril alignment (orientation index, OI). It is hypothesized that it could be possible to artificially increase the OI of the collagen fibrils and that an artificial increase in OI could increase tear strength. Ovine skins, after pickling and bating, were strained biaxially during chrome tanning. The strain ranged from 2 to 15% of the initial sample length, either uniformly in both directions by 10% or with 3% in one direction and 15% in the other. Once tanned, the leather tear strengths were measured and the collagen fibril orientation was measured using synchrotron-based small-angle X-ray scattering. The OI increased as a result of strain during tanning from 0.48 to 0.79 (P = 0.001) measured edge-on and the thickness-normalized tear strength increased from 27 to 43 N mm -1 (P leather was strained 10% in two orthogonal directions. This is evidence to support a causal relationship between high OI (measured edge-on), highly influenced by thickness, and tear strength. It also provides a method to produce stronger leather. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  19. Hydrolyzed collagen interferes with in vitro photoprotective effectiveness of sunscreens

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    Daniela D'Almeida Peres

    2017-06-01

    Full Text Available ABSTRACT The chronological skin aging is a progressive and natural process with genetic and physiological changes. However, ultraviolet (UV radiation may accelerate the oxidative stress, generating carcinogenesis and photoaging. Natural compounds and their applications are considered a trend in the cosmetic market. The protein-based film-forming compounds play an important role, once it collaborates for the better distribution of sunscreens on the skin. Here we investigated the in vitro photoprotective effectiveness of sunscreens containing the hydrolyzed collagen associated with UVA, UVB and/or inorganic filters. Sunscreens were developed with octocrylene (7.5%, butyl methoxydibenzoylmethane (avobenzone (3.0% and/or titanium dioxide (5.0%, associated or not with the hydrolyzed collagen (3.0%. In vitro photoprotective effectiveness was determined in a Labsphere(r UV2000S by the establishment of the sun protection factor (SPF and critical wavelength (nm values. Physicochemical and organoleptic characteristics were also assayed. The hydrolyzed collagen subjectively improved the formulation sensory characteristics. However, this bioactive compound led to a decrease of the SPF values of the photoprotective formulations containing octocrylene alone and octocrylene + butyl methoxydibenzoylmethane + TiO2. This inadequate interaction may be considered during the development of new sunscreens intended to contain protein-based components.

  20. Modeling Shear Induced Von Willebrand Factor Binding to Collagen

    Science.gov (United States)

    Dong, Chuqiao; Wei, Wei; Morabito, Michael; Webb, Edmund; Oztekin, Alparslan; Zhang, Xiaohui; Cheng, Xuanhong

    2017-11-01

    Von Willebrand factor (vWF) is a blood glycoprotein that binds with platelets and collagen on injured vessel surfaces to form clots. VWF bioactivity is shear flow induced: at low shear, binding between VWF and other biological entities is suppressed; for high shear rate conditions - as are found near arterial injury sites - VWF elongates, activating its binding with platelets and collagen. Based on parameters derived from single molecule force spectroscopy experiments, we developed a coarse-grain molecular model to simulate bond formation probability as a function of shear rate. By introducing a binding criterion that depends on the conformation of a sub-monomer molecular feature of our model, the model predicts shear-induced binding, even for conditions where binding is highly energetically favorable. We further investigate the influence of various model parameters on the ability to predict shear-induced binding (vWF length, collagen site density and distribution, binding energy landscape, and slip/catch bond length) and demonstrate parameter ranges where the model provides good agreement with existing experimental data. Our results may be important for understanding vWF activity and also for achieving targeted drug therapy via biomimetic synthetic molecules. National Science Foundation (NSF),Division of Mathematical Sciences (DMS).