Halogens are key cofactors in building of collagen IV scaffolds outside the cell.

Science.gov (United States)

Brown, Kyle L; Hudson, Billy G; Voziyan, Paul A

2018-05-01

The purpose of this review is to highlight recent advances in understanding the molecular assembly of basement membranes, as exemplified by the glomerular basement membrane (GBM) of the kidney filtration apparatus. In particular, an essential role of halogens in the basement membrane formation has been discovered. Extracellular chloride triggers a molecular switch within non collagenous domains of collagen IV that induces protomer oligomerization and scaffold assembly outside the cell. Moreover, bromide is an essential cofactor in enzymatic cross-linking that reinforces the stability of scaffolds. Halogenation and halogen-induced oxidation of the collagen IV scaffold in disease states damage scaffold function. Halogens play an essential role in the formation of collagen IV scaffolds of basement membranes. Pathogenic damage of these scaffolds by halogenation and halogen-induced oxidation is a potential target for therapeutic interventions.

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...

uPARAP/endo180 directs lysosomal delivery and degradation of collagen IV

DEFF Research Database (Denmark)

Kjøller, Lars; Engelholm, Lars H; Høyer-Hansen, Maria

2004-01-01

appearing uniformly within the wild-type cells after longer incubation times. In these cells, some collagen-containing vesicles were identified as lysosomes by staining for LAMP-1. In contrast, collagen IV remained extracellular and associated with fiber-like structures on uPARAP/endo180-deficient...

Insights into early extracellular matrix evolution: spongin short chain collagen-related proteins are homologous to basement membrane type IV collagens and form a novel family widely distributed in invertebrates.

Science.gov (United States)

Aouacheria, Abdel; Geourjon, Christophe; Aghajari, Nushin; Navratil, Vincent; Deléage, Gilbert; Lethias, Claire; Exposito, Jean-Yves

2006-12-01

Collagens are thought to represent one of the most important molecular innovations in the metazoan line. Basement membrane type IV collagen is present in all Eumetazoa and was found in Homoscleromorpha, a sponge group with a well-organized epithelium, which may represent the first stage of tissue differentiation during animal evolution. In contrast, spongin seems to be a demosponge-specific collagenous protein, which can totally substitute an inorganic skeleton, such as in the well-known bath sponge. In the freshwater sponge Ephydatia mülleri, we previously characterized a family of short-chain collagens that are likely to be main components of spongins. Using a combination of sequence- and structure-based methods, we present evidence of remote homology between the carboxyl-terminal noncollagenous NC1 domain of spongin short-chain collagens and type IV collagen. Unexpectedly, spongin short-chain collagen-related proteins were retrieved in nonsponge animals, suggesting that a family related to spongin constitutes an evolutionary sister to the type IV collagen family. Formation of the ancestral NC1 domain and divergence of the spongin short-chain collagen-related and type IV collagen families may have occurred before the parazoan-eumetazoan split, the earliest divergence among extant animal phyla. Molecular phylogenetics based on NC1 domain sequences suggest distinct evolutionary histories for spongin short-chain collagen-related and type IV collagen families that include spongin short-chain collagen-related gene loss in the ancestors of Ecdyzosoa and of vertebrates. The fact that a majority of invertebrates encodes spongin short-chain collagen-related proteins raises the important question to the possible function of its members. Considering the importance of collagens for animal structure and substratum attachment, both families may have played crucial roles in animal diversification.

Quaternary epitopes of α345(IV) collagen initiate Alport post-transplant anti-GBM nephritis

DEFF Research Database (Denmark)

Olaru, Florina; Luo, Wentian; Wang, Xu-Ping

2013-01-01

Alport post-transplant nephritis (APTN) is an aggressive form of anti-glomerular basement membrane disease that targets the allograft in transplanted patients with X-linked Alport syndrome. Alloantibodies develop against the NC1 domain of α5(IV) collagen, which occurs in normal kidneys, including...... of alloantibodies against allogeneic collagen IV. Some alloantibodies targeted alloepitopes within α5NC1 monomers, shared by α345NC1 and α1256NC1 hexamers. Other alloantibodies specifically targeted alloepitopes that depended on the quaternary structure of α345NC1 hexamers. In Col4a5-null mice, immunization...... with native forms of allogeneic collagen IV exclusively elicited antibodies to quaternary α345NC1 alloepitopes, whereas alloimmunogens lacking native quaternary structure elicited antibodies to shared α5NC1 alloepitopes. These results imply that quaternary epitopes within α345NC1 hexamers may initiate...

VEGF-A/Notch-Induced Podosomes Proteolyse Basement Membrane Collagen-IV during Retinal Sprouting Angiogenesis

Directory of Open Access Journals (Sweden)

Pirjo Spuul

2016-10-01

Full Text Available During angiogenic sprouting, endothelial tip cells emerge from existing vessels in a process that requires vascular basement membrane degradation. Here, we show that F-actin/cortactin/P-Src-based matrix-degrading microdomains called podosomes contribute to this step. In vitro, VEGF-A/Notch signaling regulates the formation of functional podosomes in endothelial cells. Using a retinal neovascularization model, we demonstrate that tip cells assemble podosomes during physiological angiogenesis in vivo. In the retina, podosomes are also part of an interconnected network that surrounds large microvessels and impinges on the underlying basement membrane. Consistently, collagen-IV is scarce in podosome areas. Moreover, Notch inhibition exacerbates podosome formation and collagen-IV loss. We propose that the localized proteolytic action of podosomes on basement membrane collagen-IV facilitates endothelial cell sprouting and anastomosis within the developing vasculature. The identification of podosomes as key components of the sprouting machinery provides another opportunity to target angiogenesis therapeutically.

Proteolytic processing of lysyl oxidase-like-2 in the extracellular matrix is required for crosslinking of basement membrane collagen IV.

Science.gov (United States)

López-Jiménez, Alberto J; Basak, Trayambak; Vanacore, Roberto M

2017-10-13

Lysyl oxidase-like-2 (LOXL2) is an enzyme secreted into the extracellular matrix that crosslinks collagens by mediating oxidative deamination of lysine residues. Our previous work demonstrated that this enzyme crosslinks the 7S domain, a structural domain that stabilizes collagen IV scaffolds in the basement membrane. Despite its relevant role in extracellular matrix biosynthesis, little is known about the structural requirements of LOXL2 that enable collagen IV crosslinking. In this study, we demonstrate that LOXL2 is processed extracellularly by serine proteases, generating a 65-kDa form lacking the first two scavenger receptor cysteine-rich domains. Site-specific mutagenesis to prevent proteolytic processing generated a full-length enzyme that is active in vitro toward a soluble substrate, but fails to crosslink insoluble collagen IV within the extracellular matrix. In contrast, the processed form of LOXL2 binds to collagen IV and crosslinks the 7S domain. Together, our data demonstrate that proteolytic processing is an important event that allows LOXL2-mediated crosslinking of basement membrane collagen IV. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Urinary type IV collagen is related to left ventricular diastolic function and brain natriuretic peptide in hypertensive patients with prediabetes.

Science.gov (United States)

Iida, Masato; Yamamoto, Mitsuru; Ishiguro, Yuko S; Yamazaki, Masatoshi; Ueda, Norihiro; Honjo, Haruo; Kamiya, Kaichirou

2014-01-01

Urinary type IV collagen is an early biomarker of diabetic nephropathy. Concomitant prediabetes (the early stage of diabetes) was associated with left ventricular (LV) diastolic dysfunction and increased brain natriuretic peptide (BNP) in hypertensive patients. We hypothesized that urinary type IV collagen may be related to these cardiac dysfunctions. We studied hypertensive patients with early prediabetes (HbA1c 110, n=18), those with prediabetes (HbA1c 5.7-6.4, n=98), and those with diabetes (HbA1c>6.5 or on diabetes medications, n=92). The participants underwent echocardiography to assess left atrial volume/body surface area (BSA) and the ratio of early mitral flow velocity to mitral annular velocity (E/e'). Left ventricular diastolic dysfunction (LVDD) was defined if patients had E/e'≥15, or E/e'=9-14 accompanied by left atrial volume/BSA≥32ml/mm(2). Urinary samples were collected for type IV collagen and albumin, and blood samples were taken for BNP and HbA1c. Urinary type IV collagen and albumin increased in parallel with the deterioration of glycemic status. In hypertensive patients with prediabetes, subjects with LVDD had higher levels of BNP and urinary type IV collagen than those without LVDD. In contrast, in hypertensive patients with diabetes, subjects with LVDD had higher urinary albumin and BNP than those without LVDD. Urinary type IV collagen correlated positively with BNP in hypertensive patients with prediabetes, whereas it correlated with HbA1c in those with diabetes. In hypertensive patients with prediabetes, urinary type IV collagen was associated with LV diastolic dysfunction and BNP. Copyright © 2014 Elsevier Inc. All rights reserved.

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....

Immunohistochmical Study of Glomerular Mesengial Collagen IV Expression in Diabetic Balb/c Mice

Directory of Open Access Journals (Sweden)

M. Jalali

2006-04-01

Full Text Available Introduction & Objective: Extra-cellular matrix and basement membrane play important roles in many developmental phenamenon during development and after birth. Among the components of the basement membrane, collagen fibers specially type IV, are the most important part of this area. As kidney is one of the target organs in diabetes mellitus and diabetic nephropathy is a major cause of end stage-renal disease and result an increase in morbidity and mortality of effected individuals, therefore early diagnosis leads to better treatment. The aim of this investigation was to study the primary diagnostic parameters by special regards to collagen IV fibers.Materials & Methods: In this study, 24 male balb/c mice were divided into experimental and control groups. In experimental group, the beta cells of Langerhance were chemically destroyed by an injection of 160 mg/kg alloxan and subdivided in experimental groups 1 and 2. Controls were kept untreated. Experimental group 1and 2 were sacrified 8 and 16 weeks after treatment with alloxan respectively. The same procedure was performed for control group. Immunohistochmical studies were carried out using monocolonal antibody against collagen type IV in Glomeruli. In addition, using morphometrical and stereological methods the volume of the glumerles was compared in all groups.Results: Our finding showed that in experimental groups with special regards in 16 weeks diabetic mice, the rate of collagen type IV in basement membrane around the parietal layer of Bowman capsule, mesangial cells and endothelium of capillary in glomerules increased significantly compared to controls and experimental group 1 (p<0.05, while there was not a significant difference among experimental group 2 and controls. Our data also revealed that the number of mesangial cells as well as glomerular volume increased significantly in experimental 2 (4.635±0.289×106µm3 compared to experimental 1 (3.504±0.189×106µm3 and controls (3.422�

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...

Role of 17 beta-estradiol on type IV collagen fibers volumetric density in the basement membrane of bladder wall.

Science.gov (United States)

de Fraga, Rogerio; Dambros, Miriam; Miyaoka, Ricardo; Riccetto, Cássio Luís Zanettini; Palma, Paulo César Rodrigues

2007-10-01

The authors quantified the type IV collagen fibers volumetric density in the basement membrane of bladder wall of ovariectomized rats with and without estradiol replacement. This study was conducted on 40 Wistar rats (3 months old) randomly divided in 4 groups: group 1, remained intact (control); group 2, submitted to bilateral oophorectomy and daily replacement 4 weeks later of 17 beta-estradiol for 12 weeks; group 3, sham operated and daily replacement 4 weeks later of sesame oil for 12 weeks; and group 4, submitted to bilateral oophorectomy and killed after 12 weeks. It was used in immunohistochemistry evaluation using type IV collagen polyclonal antibody to stain the fibers on paraffin rat bladder sections. The M-42 stereological grid system was used to analyze the fibers. Ovariectomy had an increase effect on the volumetric density of the type IV collagen fibers in the basement membrane of rat bladder wall. Estradiol replacement in castrated animals demonstrated a significative difference in the stereological parameters when compared to the castrated group without hormonal replacement. Surgical castration performed on rats induced an increasing volumetric density of type IV collagen fibers in the basement membrane of rats bladder wall and the estradiol treatment had a significant effect in keeping a low volumetric density of type IV collagen fibers in the basement membrane of rats bladder wall.

Irradiation Alters MMP-2/TIMP-2 System and Collagen Type IV Degradation in Brain

Energy Technology Data Exchange (ETDEWEB)

Lee, Won Hee [School of Biomedical Engineering and Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia (United States); Warrington, Junie P.; Sonntag, William E. [Reynolds Oklahoma Center on Aging, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (United States); Lee, Yong Woo, E-mail: ywlee@vt.edu [School of Biomedical Engineering and Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia (United States); Department of Biomedical Sciences and Pathobiology, Virginia Polytechnic Institute and State University, Blacksburg, Virginia (United States)

2012-04-01

Purpose: Blood-brain barrier (BBB) disruption is one of the major consequences of radiation-induced normal tissue injury in the central nervous system. We examined the effects of whole-brain irradiation on matrix metalloproteinases (MMPs)/tissue inhibitors of metalloproteinases (TIMPs) and extracellular matrix (ECM) degradation in the brain. Methods and Materials: Animals received either whole-brain irradiation (a single dose of 10 Gy {gamma}-rays or a fractionated dose of 40 Gy {gamma}-rays, total) or sham-irradiation and were maintained for 4, 8, and 24 h following irradiation. mRNA expression levels of MMPs and TIMPs in the brain were analyzed by real-time reverse transcriptase-polymerase chain reaction (PCR). The functional activity of MMPs was measured by in situ zymography, and degradation of ECM was visualized by collagen type IV immunofluorescent staining. Results: A significant increase in mRNA expression levels of MMP-2, MMP-9, and TIMP-1 was observed in irradiated brains compared to that in sham-irradiated controls. In situ zymography revealed a strong gelatinolytic activity in the brain 24 h postirradiation, and the enhanced gelatinolytic activity mediated by irradiation was significantly attenuated in the presence of anti-MMP-2 antibody. A significant reduction in collagen type IV immunoreactivity was also detected in the brain at 24 h after irradiation. In contrast, the levels of collagen type IV were not significantly changed at 4 and 8 h after irradiation compared with the sham-irradiated controls. Conclusions: The present study demonstrates for the first time that radiation induces an imbalance between MMP-2 and TIMP-2 levels and suggests that degradation of collagen type IV, a major ECM component of BBB basement membrane, may have a role in the pathogenesis of brain injury.

Irradiation Alters MMP-2/TIMP-2 System and Collagen Type IV Degradation in Brain

International Nuclear Information System (INIS)

Lee, Won Hee; Warrington, Junie P.; Sonntag, William E.; Lee, Yong Woo

2012-01-01

Purpose: Blood-brain barrier (BBB) disruption is one of the major consequences of radiation-induced normal tissue injury in the central nervous system. We examined the effects of whole-brain irradiation on matrix metalloproteinases (MMPs)/tissue inhibitors of metalloproteinases (TIMPs) and extracellular matrix (ECM) degradation in the brain. Methods and Materials: Animals received either whole-brain irradiation (a single dose of 10 Gy γ-rays or a fractionated dose of 40 Gy γ-rays, total) or sham-irradiation and were maintained for 4, 8, and 24 h following irradiation. mRNA expression levels of MMPs and TIMPs in the brain were analyzed by real-time reverse transcriptase-polymerase chain reaction (PCR). The functional activity of MMPs was measured by in situ zymography, and degradation of ECM was visualized by collagen type IV immunofluorescent staining. Results: A significant increase in mRNA expression levels of MMP-2, MMP-9, and TIMP-1 was observed in irradiated brains compared to that in sham-irradiated controls. In situ zymography revealed a strong gelatinolytic activity in the brain 24 h postirradiation, and the enhanced gelatinolytic activity mediated by irradiation was significantly attenuated in the presence of anti-MMP-2 antibody. A significant reduction in collagen type IV immunoreactivity was also detected in the brain at 24 h after irradiation. In contrast, the levels of collagen type IV were not significantly changed at 4 and 8 h after irradiation compared with the sham-irradiated controls. Conclusions: The present study demonstrates for the first time that radiation induces an imbalance between MMP-2 and TIMP-2 levels and suggests that degradation of collagen type IV, a major ECM component of BBB basement membrane, may have a role in the pathogenesis of brain injury.

Immunochemical and autoantigenic properties of the globular domain of basement membrane collagen (type IV).

Science.gov (United States)

von der Mark, H; Oberbäumer, I; Timpl, R; Kemler, R; Wick, G

1985-02-01

Polyclonal rabbit antibodies raised against the globular domain NC1 of collagen IV from human placenta and a mouse tumor react with conformational antigenic determinants present on the NC1 hexamers and also with the three major subunits obtained after dissociation. The antibodies recognized unique structures within basement membranes and showed a broad tissue reactivity but only limited species cross-reactivity. Using these antibodies, it was possible to detect small amounts of collagen IV antigens from cell cultures and in serum. Monoclonal rat antibodies against mouse NC1 revealed a similar reaction potential. Autoantibodies could be produced in mice against mouse NC1 which react with kidney and lung basement membranes in a pathological manner, mimicking Goodpasture syndrome.

Immunohistochemical Analysis of Collagen IV and Laminin Expression in Spontaneous Melanoma Regression in the Melanoma-Bearing Libechov Minipig

International Nuclear Information System (INIS)

Planska, Daniela; Burocziova, Monika; Strnadel, Jan; Horak, Vratislav

2015-01-01

Spontaneous regression (SR) of human melanoma is a rare, well-documented phenomenon that is not still fully understood. Its detailed study cannot be performed in patients due to ethical reasons. Using the Melanoma-bearing Libechov Minipig (MeLiM) animals of various ages (from 3 weeks to 8 months) we implemented a long-term monitoring of melanoma growth and SR. We focused on immunohistochemical detection of two important extracellular matrix proteins, collagen IV and laminin, which are associated with cancer. We showed that SR of melanoma is a highly dynamic process. The expression of collagen IV and laminin correlated with changes in population of melanoma cells. Tumours of 3-week-old animals consisted primarily of melanoma cells with a granular expression of collagen IV and laminin around them. Thereafter, melanoma cells were gradually destroyed and tumour tissue was rebuilt into the connective tissue. Collagen IV expression slightly increased in tumours of 10-week-old pigs showing extracellular fibrous appearance. In tumours of older animals, areas lacking melanoma cells demonstrated a low expression and areas still containing melanoma cells a high expression of both proteins. We considered the age of 10 weeks as a turning point in the transition between tumour growth and SR of the MeLiM melanoma

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.

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.

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.

Assessment of proteolytic degradation of the basement membrane: a fragment of type IV collagen as a biochemical marker for liver fibrosis

DEFF Research Database (Denmark)

Veidal, Sanne S.; Karsdal, Morten A.; Nawrocki, Arkadiusz

2011-01-01

Collagen deposition and an altered matrix metalloproteinase (MMP) expression profile are hallmarks of fibrosis. Type IV collagen is the most abundant structural basement membrane component of tissue, which increases 14-fold during fibrogenesis in the liver. Proteolytic degradation of collagens...

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

Type IV collagen as marker of fibrosis in nonalcoholic liver disease

Directory of Open Access Journals (Sweden)

Alvina Alvina

2016-02-01

Full Text Available Currently nonalcoholic fatty liver disease (NAFLD and nonalcoholic steatohepatitis (NASH are medical problems associated with the increasing prevalence of diabetes mellitus, obesity, hypertension and hypertriglyceridemia, usually designated as the metabolic syndrome associated with insulin resistance. One study demonstrated an increase in NAFLD prevalence of around 17-33% and in NASH prevalence of 5.7-16.5%. NAFLD comprises a range of mild to severe conditions, from simple steatosis to steatohepatitis, hepatic fibrosis and cirrhosis. The diagnosis of hepatic fibrosis is important for prognosis, stratification for treatment, and monitoring of treatment efficacy. Ultrasonography (USG is a simple method for detecting fatty infiltrates in the liver. USG has a sensitivity of 82-89% and a specificity of 93%, but cannot differentiate between hepatic steatosis and fibrosis. The gold standard for evaluation of hepatic fibrosis is liver biopsy, which however is a painful and invasive procedure. Currently determination of serum type IV collagen has been suggested as an alternative to liver biopsy among the non-invasive methods for evaluation of hepatic fibrosis, as its serum concentration is closely correlated with advanced hepatic fibrosis in NASH. Type IV collagen is one of the components of basement membrane and its serum concentration is indicative of degradation of the extracellular matrix.

Type IV collagen as marker of fibrosis in nonalcoholic liver disease

Directory of Open Access Journals (Sweden)

Alvina

2010-08-01

Full Text Available Currently nonalcoholic fatty liver disease (NAFLD and nonalcoholic steatohepatitis (NASH are medical problems associated with the increasing prevalence of diabetes mellitus, obesity, hypertension and hypertriglyceridemia, usually designated as the metabolic syndrome associated with insulin resistance. One study demonstrated an increase in NAFLD prevalence of around 17-33% and in NASH prevalence of 5.7-16.5%. NAFLD comprises a range of mild to severe conditions, from simple steatosis to steatohepatitis, hepatic fibrosis and cirrhosis. The diagnosis of hepatic fibrosis is important for prognosis, stratification for treatment, and monitoring of treatment efficacy. Ultrasonography (USG is a simple method for detecting fatty infiltrates in the liver. USG has a sensitivity of 82-89% and a specificity of 93%, but cannot differentiate between hepatic steatosis and fibrosis. The gold standard for evaluation of hepatic fibrosis is liver biopsy, which however is a painful and invasive procedure. Currently determination of serum type IV collagen has been suggested as an alternative to liver biopsy among the non-invasive methods for evaluation of hepatic fibrosis, as its serum concentration is closely correlated with advanced hepatic fibrosis in NASH. Type IV collagen is one of the components of basement membrane and its serum concentration is indicative of degradation of the extracellular matrix.

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

Identification of a distinct type IV collagen α chain with restricted kidney distribution and assignment of its gene to the locus of X chromosome-linked Alport syndrome

International Nuclear Information System (INIS)

Hostikka, S.L.; Hoeyhtyae, M.; Tryggvason, K.; Eddy, R.L.; Byers, M.G.; Shows, T.B.

1990-01-01

The authors have identified and extensively characterized a type IV collagen α chain, referred to as α5(IV). Four overlapping cDNA clones isolated contain an open reading frame for 543 amino acid residues of the carboxyl-terminal end of a collagenous domain, a 229-residue carboxyl-terminal noncollagenous domain, and 1201 base pairs coding for a 3' untranslated region. The collagenous Gly-Xaa-Yaa repeat sequence has five imperfections that coincide with those in the corresponding region of the α1(IV) chain. The noncollagenous domain has 12 conserved cysteine residues and 83% and 63% sequence identity with the noncollagenous domains of the α1(IV) and α2(IV) chains, respectively. The α5(IV) chain has less sequence identity with the putative bovine α3(IV) and α4(IV) chains. Antiserum against an α5(IV) synthetic peptide stained a polypeptide chain of about 185 kDa by immunoblot analysis and immunolocalization of the chain in human kidney was almost completely restricted to the glomerulus. The gene was assigned to the Xq22 locus by somatic cell hybrids and in situ hybridization. This may be identical or close to the locus of the X chromosome-linked Alport syndrome that is believed to be a type IV collagen disease

Enzyme-linked immunosorbent serum assay specific for the 7S domain of Collagen Type IV (P4NP 7S)

DEFF Research Database (Denmark)

Leeming, Diana J; Nielsen, Mette J; Dai, Yueqin

2012-01-01

Aim:  The present study describes the ability of a newly developed N-terminal pro-peptides of type IV collagen 7S domain (P4NP 7S) competitive enzyme-linked immunosorbent assay (ELISA) for describing liver fibrosis. The assay applies a monoclonal antibody specific for a PIVNP 7S epitope 100...... were significantly elevated in rat with liver fibrosis as seen by histology (CCL4: 283% elevated in the highest quartile of total hepatic collagen compared with controls, P = 0.001; BDL: 183% elevated at week 4 compared with sham, P type IV collagen...... expression in BDL rats (r = 0.49, P serum assay specific for P4NP 7S was highly related to liver fibrosis...

Ionizing radiation modulates the exposure of the HUIV26 cryptic epitope within collagen type IV during angiogenesis

International Nuclear Information System (INIS)

Brooks, Peter C.; Roth, Jennifer M.; Lymberis, Stella C.; DeWyngaert, Keith; Broek, Daniel; Formenti, Silvia C.

2002-01-01

Purpose: The majority of the research on the biologic effects of ionizing radiation has focused on the impact of radiation on cells in terms of gene expression, DNA damage, and cytotoxicity. In comparison, little information is available concerning the direct effects of radiation on the extracellular microenvironment, specifically the extracellular matrix and its main component, collagen. We have developed a series of monoclonal antibodies that bind to cryptic epitopes of collagen Type IV that are differentially exposed during matrix remodeling and are key mediators of angiogenesis. We have hypothesized that ionizing radiation might affect the process of angiogenesis through a direct effect on the extracellular matrix and specifically on collagen Type IV. Methods and Materials: Angiogenesis was induced in a chick chorioallantoic membrane (CAM) model; 24 h later, a single-dose treatment with ionizing radiation (0.5, 5, and 20 cGy) was administered. Angiogenesis was assessed, and the exposure of two cryptic regulatory epitopes within collagen Type IV (HUI77 and HUIV26) was studied in vitro by solid-phase ELISA and in vivo by immunofluorescence staining. Results: A dose-dependent reduction of angiogenesis with maximum inhibition (85%-90%) occurring at 20 cGy was demonstrated in the CAM model. Exposure of the cryptic HUIV26 site, an angiogenesis control element, was inhibited both in vitro and in vivo by the same radiation dose, whereas little if any change was observed for the HUI77 cryptic epitope. Conclusions: A dose-dependent alteration of the functional exposure of the HUIV26 cryptic epitope is induced by radiation in vitro and in the CAM model in vivo. This radiation-induced change in protein structure and function may contribute to the inhibitory effects of ionizing radiation on new blood vessel growth and warrants further studies in other models

Matrix metalloproteinase-2 and its correlation with basal membrane components laminin-5 and collagen type IV in paediatric burn patients measured with Surface Plasmon Resonance Imaging (SPRI) biosensors.

Science.gov (United States)

Weremijewicz, Artur; Matuszczak, Ewa; Sankiewicz, Anna; Tylicka, Marzena; Komarowska, Marta; Tokarzewicz, Anna; Debek, Wojciech; Gorodkiewicz, Ewa; Hermanowicz, Adam

2018-01-30

The purpose of this study was the determination of matrix metalloproteinase-2 and its correlation with basal membrane components laminin-5 and collagen type IV in the blood plasma of burn patients measured with Surface Plasmon Resonance Imaging (SPRI) biosensors. 31 children scalded by hot water who were managed at the Department of Paediatric Surgery between 2014-2015, after primarily presenting with burns in 4-20% TBSA were included into the study (age 9 months up to 14 years, mean age 2,5+1 years). There were 10 girls and 21 boys. Venous blood samples were drawn 2-6h, and 12-16h after the thermal injury, and on the subsequent days 3, 5 and 7. The matrix metalloproteinase-2, collagen type IV and laminin-5 concentrations were assessed using Surface Plasmon Resonance Imaging by the investigators blinded to the other data. The MMP-2, laminin-5 and collagen type IV concentrations in the blood plasma of patients with burns, were highest 12-16h after thermal injury, the difference was statistically significant. The MMP-2, laminin-5 and collagen type IV concentrations measured 3 days, 5 days and 7 days after the thermal injury, slowly decreased over time, and on the 7th day reached the normal range, when compared with the concentration measured in controls. Current work is the first follow-up study regarding MMP-2 in burns. MMP-2, laminin-5 and collagen type IV levels were elevated early after burn injury in the plasma of studied patients, and were highest 12-16h after the injury. MMP-2, laminin-5 and collagen type IV levels were not proportional to the severity of the burn. We believe in the possibility that the gradual decrease of MMP-2, collagen type IV and laminin-5 concentrations could be connected with the process of healing, but to prove it, more investigation is needed in this area. The SPR imaging biosensor is a good diagnostic tool for determination of MMP-2, laminin-5 and collagen type IV in blood plasma of patients with burns. Copyright © 2017 Elsevier Ltd

Combined determination of serum type IV collagen with urine Tamm-Horsfall protein and albumin for early diagnosis in diabetic retinopathy

International Nuclear Information System (INIS)

Wang Hong; Zhang Aihua; Ren Yuguo

2003-01-01

Objective: To study the relationship between changes of serum type IV collagen, urine Tamm-horsfall protein, albumin and development of diabetic retinopathy (DR) in patients with type 2 diabetes mellitus. Methods: Serum CIV, urine THP and Alb were determined with ELISA and RIA respectively in 76 patients with type 2 diabetes mellitus (NDR26, BDR26, PDR24) and 30 controls. Results: Values of the three markers were significantly different among the three groups of patients (p < 0.01; p < 0.01; p < 0.001 respectively). Conclusion: Serum type IV collagens, urine Tamm-Horsfall protein and albumin were sensitive indicators in predicting diabetic retinopathy

Extraction Socket Preservation Using Porcine-Derived Collagen Membrane Alone or Associated with Porcine-Derived Bone. Clinical Results of Randomized Controlled Study

Directory of Open Access Journals (Sweden)

Renzo Guarnieri

2017-03-01

Full Text Available Objectives: The aim of present randomized controlled clinical trial was to clinically evaluate hard tissue changes after extraction socket preservation procedures compared to natural spontaneous healing. Material and Methods: Thirty patients were enrolled in the present study and underwent single-tooth extraction in the premolar/molar areas. Ten sites were grafted with porcine-derived bone covered by collagen membrane, 10 covered by porcine-derived collagen membrane alone, and 10 underwent natural spontaneous healing. Vertical and horizontal bone changes after 3-month were evaluated at implant placement. Results: The vertical and horizontal bone changes at the extraction sockets treated with collagen membrane alone (vertical: -0.55 [SD 0.11] mm, and horizontal: -1.21 [SD 0.69] mm and collagen membrane plus porcine-derived bone (vertical: -0.37 [SD 0.7] mm, and horizontal: -0.91 [SD 0.53] mm were found significantly lower (P < 0.001, when compared to non-grafted sockets (vertical: -2.09 [SD 0.19] mm, and horizontal: -3.96 [SD 0.87] mm. In type 1 extraction sockets, in premolar sites, and in presence of vestibular bone thicknesses ≥ 1.5 mm, the use of collagen membrane alone revealed similar outcomes to those with additional graft material. Conclusions: At the re-entry surgery, extraction sockets grafted with porcine-derived bone and covered by collagen membrane, and extraction sockets covered by porcine-derived collagen membrane alone, showed significantly lower vertical and horizontal bone changes, compared to extraction sockets sites underwent natural spontaneous healing. However, a complete prevention of remodelling is not achievable, irrespective of the technique used.

Clinical significance of determination of serum collagen type IV (IV-C) and transforming growth factor beta1(TGF-β1) levels in patients with diabetic nephropathy

International Nuclear Information System (INIS)

Xie Hongfang; Peng Liang

2006-01-01

Objective: To investigate the clinical significance of determination of serum collagen type IV (IV-C) and transforming growth factor beta 1 (TGF-β 1 ) levels in patients with diabetic nephropathy. Methods: Serum IV-C levels ( with RIA) and TGF-β 1 levels (with ELISA) were determined in 30 controls and 105 patients with type II diabetis mellitus (45 with diabetic nephropathy and 60 without nephropathy). Results: The serum levels of IV-C and TGF-β 1 in diabetic patients with nephropathy were significantly higher than those in controls (P 0.05). Conclusion: Serum IV-C and TGF-β 1 , levels increased gradually as the diabetic nephropathy got more severe, they could be used as sensitive markers for early diagnosis of development of diabetic nephropathy. (authors)

Expression of type IV collagen in different histological grades of oral squamous cell carcinoma: An immunohistochemical study

Directory of Open Access Journals (Sweden)

Pankaj Agarwal

2013-01-01

Conclusion: The results indicated that there was a direct relationship between the presence of type IV collagen and the differentiation degree of SCC cells and thus that SCC cells loose their capability to form the basement membrane as they become less differentiated.

Proteolysis breaks tolerance toward intact α345(IV) collagen, eliciting novel anti-GBM autoantibodies specific for α345NC1 hexamers

Science.gov (United States)

Olaru, Florina; Wang, Xu-Ping; Luo, Wentian; Ge, Linna; Miner, Jeffrey H; Kleinau, Sandra; Geiger, Xochiquetzal J.; Wasiluk, Andrew; Heidet, Laurence; Kitching, A. Richard; Borza, Dorin-Bogdan

2012-01-01

Goodpasture disease is an autoimmune kidney disease mediated by autoAbs against NC1 monomers of α3(IV) collagen that bind to the glomerular basement membrane (GBM), usually causing rapidly progressive glomerulonephritis. We identified a novel type of human IgG4-restricted anti-GBM autoAbs associated with mild non-progressive glomerulonephritis, which specifically targeted α345NC1 hexamers but not α3NC1 monomers. The mechanisms eliciting these anti-GBM autoAbs were investigated in mouse models recapitulating this phenotype. Wild type and FcγRIIB−/− mice immunized with autologous murine GBM NC1 hexamers produced mouse IgG1-restricted autoAbs specific for α345NC1 hexamers, which bound to the GBM in vivo but did not cause glomerulonephritis. In these mice, intact collagen IV from murine GBM was not immunogenic. However, in Col4a3−/− Alport mice, both intact collagen IV and NC1 hexamers from murine GBM elicited IgG antibodies specific for α3α4α5NC1 hexamers, which were not subclass restricted. As heterologous antigen in COL4A3-humanized mice, murine GBM NC1 hexamers elicited mouse IgG1, IgG2a and IgG2b autoAbs specific for α345NC1 hexamers and induced anti-GBM Ab glomerulonephritis. These findings indicate that tolerance toward autologous intact α3α4α5(IV) collagen is established in hosts expressing this antigen, even though autoreactive B cells specific for α345NC1 hexamers are not purged from their repertoire. Proteolysis selectively breaches this tolerance by generating autoimmunogenic α3α4α5NC1 hexamers. This provides a mechanism eliciting autoAbs specific for α345NC1 hexamers, which are restricted to non-inflammatory IgG subclasses and non-nephritogenic. In Alport syndrome, lack of tolerance toward α3α4α5(IV) collagen promotes production of alloantibodies to α345NC1 hexamers, including pro-inflammatory IgG subclasses which mediate post-transplant anti-GBM nephritis. PMID:23303673

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.

Alterations of type IV collagen alpha chains in patients with chronic acquired glomerulopathies: mRNA levels, protein expression and urinary loss.

Science.gov (United States)

Sanna-Cherchi, Simone; Carnevali, Maria Luisa; Martorana, Davide; Cravedi, Paolo; Maggiore, Umberto; Alinovi, Rossella; Bovino, Achiropita; Mattei, Silvia; Orlandini, Guido; Gatti, Rita; Savi, Mario; Sado, Yoshikazu; Neri, Tauro M; Allegri, Landino

2007-01-01

Type IV collagen is a major structural component of the normal kidney glomerulus. However, its role in chronic acquired glomerulopathies has been only partially elucidated. Urinary levels of col(IV)alpha1, col(IV)alpha3 and col(IV)alpha5 collagen chains were analyzed in 107 patients with chronic acquired glomerulopathies. In a subgroup of 33 patients, tissue mRNA levels, protein expression and urinary excretion were evaluated for all col(IV)alpha chains, from col(IV)alpha1 to col(IV)alpha5. The renal specimens were examined to get a semiquantitative score of the acute and chronic activity of the histological lesions. Urines obtained from 13 healthy subjects and 10 normal renal tissue samples were used as controls. Urinary levels of col(IV)alpha1, col(IV)alpha3, col(IV)alpha5 chains were significantly higher in patients than in controls [p < 0.01 for all], while only col(IV)alpha1 and col(IV)alpha3 urinary excretion correlated with the degree of chronic histological damage [col(IV)alpha1 R = 0.44, p < 0.001; col(IV)alpha3: R = 0.47, p < 0.001]. Compared with controls, patients showed a renal expression of mRNA for col(IV)alpha5 chain significantly higher [p = 0.001], while having a significantly lower protein expression of col(IV)alpha3, col(IV)alpha4 and col(IV)alpha5 chains [p < 0.01 for all]. Patients with chronic acquired glomerulopathies show important alterations in the col(IV)alpha chain network mimicking some molecular features of the X-linked Alport's syndrome. Further studies are needed to show whether urinary levels of the col(IV)alpha chains may be used as markers for monitoring renal injury. Copyright 2007 S. Karger AG, Basel.

The Chemical Chaperone, PBA, Reduces ER Stress and Autophagy and Increases Collagen IV α5 Expression in Cultured Fibroblasts From Men With X-Linked Alport Syndrome and Missense Mutations

Directory of Open Access Journals (Sweden)

Dongmao Wang

2017-07-01

Discussion: Sodium 4-phenylbutyrate increases collagen IV α5 mRNA levels, reduces ER stress and autophagy, and possibly facilitates collagen IV α5 extracellular transport. Whether these actions delay end-stage renal failure in men with X-linked Alport syndrome and missense mutations will only be determined with clinical trials.

Urinary collagen IV and πGST: potential biomarkers for detecting localized kidney injury in diabetes--a pilot study.

LENUS (Irish Health Repository)

Cawood, T J

2010-01-01

Urinary biomarkers can identify damage to specific parts of the nephron. We performed a cross-sectional study to characterise the pattern of diabetic nephropathy using urinary biomarkers of glomerular fibrosis (collagen IV), proximal tubular damage (α-glutathione-S-transferase, GST) and distal tubular damage (πGST).

Peptides Derived from Type IV Collagen, CXC Chemokines, and Thrombospondin-1 Domain-Containing Proteins Inhibit Neovascularization and Suppress Tumor Growth in MDA-MB-231 Breast Cancer Xenografts

Directory of Open Access Journals (Sweden)

Jacob E. Koskimaki

2009-12-01

Full Text Available Angiogenesis or neovascularization, the process of new blood vessel formation from preexisting microvasculature, involves interactions among several cell types including parenchymal, endothelial cells, and immune cells. The formation of new vessels is tightly regulated by a balance between endogenous proangiogenic and antiangiogenic factors to maintain homeostasis in tissue; tumor progression and metastasis in breast cancer have been shown to be angiogenesis-dependent. We previously introduced a systematic methodology to identify putative endogenous antiangiogenic peptides and validated these predictions in vitro in human umbilical vein endothelial cell proliferation and migration assays. These peptides are derived from several protein families including type IV collagen, CXC chemokines, and thrombospondin-1 domain-containing proteins. On the basis of the results from the in vitro screening, we have evaluated the ability of one peptide selected from each family named pentastatin-1, chemokinostatin-1, and properdistatin, respectively, to suppress angiogenesis in an MDA-MB-231 human breast cancer orthotopic xenograft model in severe combined immunodeficient mice. Peptides were administered intraperitoneally once per day. We have demonstrated significant suppression of tumor growth in vivo and subsequent reductions in microvascular density, indicating the potential of these peptides as therapeutic agents for breast cancer.

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...

Immunohistochemical Analysis of Collagen IV and Laminin Expression in Spontaneous Melanoma Regression in the Melanoma-Bearing Libechov Minipig

Czech Academy of Sciences Publication Activity Database

Plánská, Daniela; Burocziová, Monika; Strnádel, Ján; Horák, Vratislav

2015-01-01

Roč. 48, č. 1 (2015), s. 15-26 ISSN 0044-5991 R&D Projects: GA MŠk ED2.1.00/03.0124 Institutional support: RVO:67985904 ; RVO:61388971 Keywords : collagen IV * laminin * MeLiM * porcine melanoma * spontaneous regression Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.912, year: 2015

A biomimetic collagen derived peptide exhibits anti-angiogenic activity in triple negative breast cancer.

Directory of Open Access Journals (Sweden)

Elena V Rosca

Full Text Available We investigated the application of a mimetic 20 amino acid peptide derived from type IV collagen for treatment of breast cancer. We showed that the peptide induced a decrease of proliferation, adhesion, and migration of endothelial and tumor cells in vitro. We also observed an inhibition of triple negative MDA-MB-231 xenograft growth by 75% relative to control when administered intraperitoneally for 27 days at 10 mg/kg. We monitored in vivo the changes in vascular properties throughout the treatment using MRI and found that the vascular volume and permeability surface area product decreased significantly. The treatment also resulted in an increase of caspase-3 activity and in a reduction of microvascular density. The multiple mode of action of this peptide, i.e., anti-angiogenic, and anti-tumorigenic, makes it a viable candidate as a therapeutic agent as a monotherapy or in combination with other compounds.

Different assembly of type IV collagen on hydrophilic and hydrophobic substrata alters endothelial cells interaction

Directory of Open Access Journals (Sweden)

NM Coelho

2010-06-01

Full Text Available Considering the structural role of type IV collagen (Col IV in the assembly of the basement membrane (BM and the perspective of mimicking its organization for vascular tissue engineering purposes, we studied the adsorption pattern of this protein on model hydrophilic (clean glass and hydrophobic trichloro(octadecylsilane (ODS surfaces known to strongly affect the behavior of other matrix proteins. The amount of fluorescently labeled Col IV was quantified showing saturation of the surface for concentration of the adsorbing solution of about 50μg/ml, but with approximately twice more adsorbed protein on ODS. AFM studies revealed a fine – nearly single molecular size – network arrangement of Col IV on hydrophilic glass, which turns into a prominent and growing polygonal network consisting of molecular aggregates on hydrophobic ODS. The protein layer forms within minutes in a concentration-dependent manner. We further found that human umbilical vein endothelial cells (HUVEC attach less efficiently to the aggregated Col IV (on ODS, as judged by the significantly altered cell spreading, focal adhesions formation and the development of actin cytoskeleton. Conversely, the immunofluorescence studies for integrins revealed that the fine Col IV network formed on hydrophilic substrata is better recognized by the cells via both α1 and α2 heterodimers which support cellular interaction, apart from these on hydrophobic ODS where almost no clustering of integrins was observed.

Long-term Culture of Human iPS Cell-derived Telencephalic Neuron Aggregates on Collagen Gel.

Science.gov (United States)

Oyama, Hiroshi; Takahashi, Koji; Tanaka, Yoshikazu; Takemoto, Hiroshi; Haga, Hisashi

2018-01-01

It takes several months to form the 3-dimensional morphology of the human embryonic brain. Therefore, establishing a long-term culture method for neuronal tissues derived from human induced pluripotent stem (iPS) cells is very important for studying human brain development. However, it is difficult to keep primary neurons alive for more than 3 weeks in culture. Moreover, long-term adherent culture to maintain the morphology of telencephalic neuron aggregates induced from human iPS cells is also difficult. Although collagen gel has been widely used to support long-term culture of cells, it is not clear whether human iPS cell-derived neuron aggregates can be cultured for long periods on this substrate. In the present study, we differentiated human iPS cells to telencephalic neuron aggregates and examined long-term culture of these aggregates on collagen gel. The results indicated that these aggregates could be cultured for over 3 months by adhering tightly onto collagen gel. Furthermore, telencephalic neuronal precursors within these aggregates matured over time and formed layered structures. Thus, long-term culture of telencephalic neuron aggregates derived from human iPS cells on collagen gel would be useful for studying human cerebral cortex development.Key words: Induced pluripotent stem cell, forebrain neuron, collagen gel, long-term culture.

Rethinking Molecular Mimicry in Rheumatic Heart Disease andAutoimmune Myocarditis: Laminin, Collagen IV, CAR and B1AR as Initial Targets of Disease

Directory of Open Access Journals (Sweden)

Robert eRoot-Bernstein

2014-08-01

Full Text Available Rationale: Molecular mimicry theory (MMT suggests that epitope mimicry between pathogens and human proteins can activate autoimmune disease. Group A streptococci (GAS mimics human cardiac myosin in rheumatic heart disease (RHD and coxsackie viruses (CX mimic actin in autoimmune myocarditis (AM. But myosin and actin are immunologically inaccessible and unlikely initial targets. Extracellular cardiac proteins that mimic GAS and CX would be more likely.Objectives: To determine whether extracellular cardiac proteins such as coxsackie and adenovirus receptor (CAR, beta 1 adrenergic receptor (B1AR, CD55/DAF, laminin, and collagen IV mimic GAS, CX and/or cardiac myosin or actin. Methods: BLAST 2.0 and LALIGN searches of the UniProt protein database were employed to identify potential molecular mimics. Quantitative ELISA was used to measure antibody cross-reactivity. Measurements: Similarities were considered to be significant if a sequence contained at least 5 identical amino acids in 10. Antibodies were considered to be cross-reactive if the binding constant had a Kd less than 10-9 M. Main Results: GAS mimics laminin, CAR and myosin. CX mimics actin and collagen IV and B1AR. The similarity search results are mirrored by antibody cross-reactivities. Additionally, antibodies against laminin recognize antibodies against collagen IV; antibodies against actin recognize antibodies against myosin, and antibodies against GAS recognize antibodies against CX. Thus, there is both mimicry of extracellular proteins and antigenic complementarity between GAS-CX in RHD/AM.Conclusions: RHD/AM may be due to combined infections of GAS with CX localize at cardiomyocytes may produce a synergistic, hyperinflammatory response that cross-reacts with laminin, collagen IV, CAR and/or B1AR. Epitope drift shifts the immune response to myosin and actin after cardiomyocytes become damaged.

Tumstatin, a Matrikine Derived from Collagen Type IVα3, is Elevated in Serum from Patients with Non-Small Cell Lung Cancer

DEFF Research Database (Denmark)

Nielsen, Signe Holm; Willumsen, Nicholas; Brix, Susanne

2018-01-01

of patients with idiopathic pulmonary fibrosis (IPF), chronic obstructive pulmonary disease (COPD), and non–small cell lung cancer (NSCLC) belonging to two cohorts. RESULTS: The developed TUM enzyme-linked immunosorbent assay (ELISA) was technically robust. In cohort 1, levels of TUM were significantly higher......OBJECTIVES: Fibrosis and cancer are characterized by extracellular matrix (ECM) remodeling. The basement membrane is mainly composed by collagen type IV and laminin. Tumstatin is a matrix metalloproteinase-9 (MMP-9) generated matrikine of collagen type IV α3 chain. We evaluated the potential...

Significance of combinative determination of urinary type IV collagen and trace albumin in type 2 diabetics

International Nuclear Information System (INIS)

Yang Libin

2004-01-01

In order to evaluate the diagnostic value of combinative determination of urinary trace albumin(Alb) and urinary type IV collagen (C-IV) for early damage of renal function in type 2 diabetics, 24-hr urine was collected each from 30 normal subjects and 165 type 2 diabetics, and RIA was carried out to determine simultaneously Alb and C-IV (concentration method). The results showed: (1) the content of Alb in 24-hr urine of normal subjects was 6.45±2.04 mg/24 hrs, and that of C-IV was 86.68 ± 11.98 μg/L; (2) The type 2 diabetics were divided into A and B groups according to their Alb content in 24-hr urine. In group A(n=130) the Alb content was ≥30 mg/24 hrs and their C-IV was 120.03 ± 34.02 μg/L, whereas in group B(n=35) the corresponding values were < 30 mg/24 hrs and 97.14 ± 24.93 μg/L, respectively. Conclusion: When the Alb content of type 2 diabetics is still within the normal upper limit, the level of C-IV has already been elevated in part of them, indicating C-IV level can be more able to reflect early damage of renal function in type 2 diabetics than Alb content does. (authors)

Effect of macrophage and matrix metalloproteinase-9 on proliferation of pulmonary fibroblast and synthesis of collagen IV

International Nuclear Information System (INIS)

Song Liangwen; Sun Li; Diao Ruiying; Li Yang; Zhang Yong; Yin Jiye

2006-01-01

Objective: To explore pathogenetic mechanism in initiation of radiation-induced pulmonary fibrosis. Methods: Alveolar macrophages in Wistar rats irradiated by 60 Co γ-ray were collected by alveolar lavage; condition medium was prepared for stimulating human lung fibroblast (HLF) proliferation; HLF proliferation activity was determined by MTT method; collagen IV (Col IV) in HLF was determined by Western blot; the activity of matrix metalloproteinase-9 (MMP-9) was determined by zymography. Results: HLF proliferation activity was significantly increased after stimulation of condition medium, and the increase was most evident within 48-72 hs. Col IV synthesis in HLF was increased and reached a peak at 12 h after stimulation and then began to decrease. MMP-9 activity began to increase at 12 h and reached a peak at 48 h and then decreased after 72 h. Conclusions: Cobalt-60 gamma ray irradiation of 20 Gy can stimulate secretion of some cytokines in alveolar macrophage to promote pulmonary interstitial fibroblast proliferation and synthesis of Col IV . Col IV can stimulate MMP-9 increase; MMP-9 can degrade excess Col IV. Such changes are involved in remodeling process of early pulmonary injury. (authors)

Microbial BOD sensors based on Zr (IV)-loaded collagen fiber.

Science.gov (United States)

Zhao, Lei; He, Li; Chen, Shujuan; Zou, Likou; Zhou, Kang; Ao, Xiaolin; Liu, Shuliang; Hu, Xinjie; Han, Guoquan

2017-03-01

Biochemical oxygen demand (BOD) sensors based on Zr (IV)-loaded collagen fiber (ZrCF), a novel material with great porous structure, were developed. This novel material shows adsorbability by microorganisms. Saccharomyces cerevisiae and Escherichia coli were used for the construction of BOD sensors. Factors affecting BOD sensor performance were examined. The ZrCF-based BOD sensor showed different sensitivities and linear response ranges with different biofilm densities. The amount of microorganisms strongly affected the performance of the BOD sensor. Poor permeability of previously reported immobilization carriers were greatly circumvented by ZrCF. The service life of the ZrCF-based BOD sensor was more than 42 days. The immobilized microorganisms can be stored for more than 6 months under 4°C in PB solution. There was good correlation between the results of the sensor method and the standard 5-day BOD method in the determination of pure organic substrates and real water samples. Copyright © 2016 Elsevier Inc. All rights reserved.

Identification of the NC1 domain of {alpha}3 chain as critical for {alpha}3{alpha}4{alpha}5 type IV collagen network assembly.

Science.gov (United States)

LeBleu, Valerie; Sund, Malin; Sugimoto, Hikaru; Birrane, Gabriel; Kanasaki, Keizo; Finan, Elizabeth; Miller, Caroline A; Gattone, Vincent H; McLaughlin, Heather; Shield, Charles F; Kalluri, Raghu

2010-12-31

The network organization of type IV collagen consisting of α3, α4, and α5 chains in the glomerular basement membrane (GBM) is speculated to involve interactions of the triple helical and NC1 domain of individual α-chains, but in vivo evidence is lacking. To specifically address the contribution of the NC1 domain in the GBM collagen network organization, we generated a mouse with specific loss of α3NC1 domain while keeping the triple helical α3 chain intact by connecting it to the human α5NC1 domain. The absence of α3NC1 domain leads to the complete loss of the α4 chain. The α3 collagenous domain is incapable of incorporating the α5 chain, resulting in the impaired organization of the α3α4α5 chain-containing network. Although the α5 chain can assemble with the α1, α2, and α6 chains, such assembly is incapable of functionally replacing the α3α4α5 protomer. This novel approach to explore the assembly type IV collagen in vivo offers novel insights in the specific role of the NC1 domain in the assembly and function of GBM during health and disease.

Adsorption recovery of thorium(IV) by Myrica rubra tannin and larch tannin immobilized onto collagen fibres

International Nuclear Information System (INIS)

Xuepin Liao; Li Li; Bi Shi

2004-01-01

Novel adsorbents which can concentrate Th(IV) in aqueous solution were prepared by immobilizing Myrica rubra tannin and larch tannin onto collagen fibre matrices. The adsorption capacities of the immobilized tannins to Th(IV) are related to temperature and pH value of the adsorption process. For example, when the initial concentration of Th(IV) was 116.0 mg x l -1 and the immobilized tannin was 100 mg, the adsorption capacities of immobilized Myrica rubra tannin and larch tannin were 55.98 mg Th(IV) x g -1 and 13.19 mg Th(IV) x g -1 , respectively at 303 K, and 73.67 mg Th(IV) x g -1 and 18.19 mg Th(IV) x g -1 at 323 K. It was also found that the higher adsorption capacity was obtained at higher pH value. The adsorption equilibrium data of the immobilized tannins for Th(IV) can be well fitted by the Langmuir model and the mechanism of the adsorption was found to be a chemical adsorption. In general, the adsorption capacity of immobilized Myrica rubra tannin to Th(IV) is significantly higher than that of immobilized larch tannin, probably due to the fact that the B ring of Myrica rubra tannin has a pyrogallol structure which has higher reaction activity with metal ions. The breakthrough point of the adsorption column of immobilized Myrica rubra tannin was at 33 bed volumes for the experimental system. The mass transfer coefficient of adsorption column determined by Adams-Bohart equation was 1.61 x 10 -4 l x mg -1 x min -1 . The adsorption column can be easily regenerated by 0.1 mol x l -1 HNO 3 solution, showing outstanding ability of concentrating Th(IV). (author)

Disruption of fibronectin matrix affects type IV collagen, fibrillin and laminin deposition into extracellular matrix of human trabecular meshwork (HTM) cells.

Science.gov (United States)

Filla, Mark S; Dimeo, Kaylee D; Tong, Tiegang; Peters, Donna M

2017-12-01

Fibronectin fibrils are a major component of the extracellular matrix (ECM) of the trabecular meshwork (TM). They are a key mediator of the formation of the ECM which controls aqueous humor outflow and contributes to the pathogenesis of glaucoma. The purpose of this work was to determine if a fibronectin-binding peptide called FUD, derived from the Streptococcus pyogenes Functional Upstream Domain of the F1 adhesin protein, could be used to control fibronectin fibrillogenesis and hence ECM formation under conditions where its expression was induced by treatment with the glucocorticoid dexamethasone. FUD was very effective at preventing fibronectin fibrillogenesis in the presence or absence of steroid treatment as well as the removal of existing fibronectin fibrils. Disruption of fibronectin fibrillogenesis by FUD also disrupted the incorporation of type IV collagen, laminin and fibrillin into the ECM. The effect of FUD on these other protein matrices, however, was found to be dependent upon the maturity of the ECM when FUD was added. FUD effectively disrupted the incorporation of these other proteins into matrices when added to newly confluent cells that were forming a nascent ECM. In contrast, FUD had no effect on these other protein matrices if the cell cultures already possessed a pre-formed, mature ECM. Our studies indicate that FUD can be used to control fibronectin fibrillogenesis and that these fibrils play a role in regulating the assembly of other ECM protein into matrices involving type IV collagen, laminin, and fibrillin within the TM. This suggests that under in vivo conditions, FUD would selectively disrupt fibronectin fibrils and de novo assembly of other proteins into the ECM. Finally, our studies suggest that targeting fibronectin fibril assembly may be a viable treatment for POAG as well as other glaucomas involving excessive or abnormal matrix deposition of the ECM. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tissue-engineered cartilaginous constructs for the treatment of caprine cartilage defects, including distribution of laminin and type IV collagen.

Science.gov (United States)

Jeng, Lily; Hsu, Hu-Ping; Spector, Myron

2013-10-01

The purpose of this study was the immunohistochemical evaluation of (1) cartilage tissue-engineered constructs; and (2) the tissue filling cartilage defects in a goat model into which the constructs were implanted, particularly for the presence of the basement membrane molecules, laminin and type IV collagen. Basement membrane molecules are localized to the pericellular matrix in normal adult articular cartilage, but have not been examined in tissue-engineered constructs cultured in vitro or in tissue filling cartilage defects into which the constructs were implanted. Cartilaginous constructs were engineered in vitro using caprine chondrocyte-seeded type II collagen scaffolds. Autologous constructs were implanted into 4-mm-diameter defects created to the tidemark in the trochlear groove in the knee joints of skeletally mature goats. Eight weeks after implantation, the animals were sacrificed. Constructs underwent immunohistochemical and histomorphometric evaluation. Widespread staining for the two basement membrane molecules was observed throughout the extracellular matrix of in vitro and in vivo samples in a distribution unlike that previously reported for cartilage. At sacrifice, 70% of the defect site was filled with reparative tissue, which consisted largely of fibrous tissue and some fibrocartilage, with over 70% of the reparative tissue bonded to the adjacent host tissue. A novel finding of this study was the observation of laminin and type IV collagen in in vitro engineered cartilaginous constructs and in vivo cartilage repair samples from defects into which the constructs were implanted, as well as in normal caprine articular cartilage. Future work is needed to elucidate the role of basement membrane molecules during cartilage repair and regeneration.

Development of a Novel Scaffold of Chitosan, Type IV Collagen and Integrin α3β1 As Alternative Scaffold for Primary Culture of Podocytes

Directory of Open Access Journals (Sweden)

Diana Ginette Zárate-Triviño

2018-06-01

Full Text Available Loss of podocytes has been a main pathology present in renal diseases; the leak of these specialized cells increases the permeability of the glomerular basal membrane (GMB and protein release affecting the glomeruli, the main structure of the kidney. The study of different physiopathology mechanism has been a challenge because of the short lifetime of podocytes in vitro. We obtained and characterized composites based on Chitosan (CTS, polyvinyl alcohol (PVA, type IV collagen and integrin α3β1 as a possible application in primary culture of podocytes. Podocytes were extracted from the urine of patients with Idiopathic Nephrotic Syndrome (INS. To evaluate biocompatibility, we assessed cell viability through the lactate dehydrogenase assay. Immunohistochemical staining was used to detect the expression of specific proteins from podocytes such as podocin, and podocalyxin and CD80, a marker of cellular stress. The results showed that our synthesis method promotes the copolymerization of the components in the scaffold. Due to its reactivity, the amine group of chitosan made links with type IV collagen and integrin α3β1. The swelling and degradation tests allowed us to select the material with the best mechanical properties for cellular culture. The expression of podocin and podocalyxin remains the same in the culture of podocytes on the scaffold; in contrast, CD80 expression increased. The viability of podocytes cultured on the CTS/PVA/type IV collagen/integrin α3β1 scaffold increased in comparison to the culture control.

Chemical nature of implant-derived titanium(IV) ions in synovial fluid

International Nuclear Information System (INIS)

Silwood, Christopher J.L.; Grootveld, Martin

2005-01-01

Previous investigations have indicated a deleterious leakage of Ti(III) and/or Ti(IV) species from Ti-Al-V alloy joint prostheses into adjacent tissue, synovium or synovial fluid (SF) in vivo. In view of the importance of the particular chemical nature of such complexes in determining their biological activity, we have employed high field proton ( 1 H) NMR spectroscopy to 'speciate' Ti(IV) in inflammatory SF. Treatment of osteoarthritic SF samples with increasing concentrations of Ti(IV) (0.10-1.03 mM [TiO(C 2 O 4 ) 2 ] 2- ) gave rise to a specific broadening of the citrate proton resonances, indicating that this bioavailable oxygen-donor ligand plays an important role in complexing implant-derived Ti(IV). 1 H NMR analysis of Ti(IV)-loaded SF samples subsequently treated with a large excess of ascorbate (0.05 M) showed that this added Ti(IV) chelator was only poorly effective in removing this metal ion from Ti(IV)-citrate/Ti(IV)-oxycitrate complexes. The results obtained here provide evidence for complexation of the low-molecular-mass (non-protein-bound) fraction of implant-derived Ti(IV) by citrate in vivo

Physiochemical properties and resorption progress of porcine skin-derived collagen membranes: In vitro and in vivo analysis.

Science.gov (United States)

An, Yin-Zhe; Kim, You-Kyoung; Lim, Su-Min; Heo, Yeong-Ku; Kwon, Mi-Kyung; Cha, Jae-Kook; Lee, Jung-Seok; Jung, Ui-Won; Choi, Seong-Ho

2018-03-30

The aim of the present study was to evaluate the physiochemical properties and resorption progress of two cross-linked, porcine skin-derived collagen membranes and compare their features with those of a membrane without cross-linking (Bio-Gide ® [BG], Geistlich Biomaterials, Wolhusen, Switzerland). Three porcine skin-derived collagen membranes, dehydrothermally (DHT) cross-linked (experimental), DHT and 1-ethyl-3(3-dimethylaminopropyl)-carbodiimide (DHT/EDC) cross-linked (experimental) and BG were investigated for their morphology, enzyme resistance, and tensile strength in vitro and biodegradation in vivo. DHT and DHT/EDC membranes exhibited irregular, interconnected macro- and micropores that formed a 3D mesh, whereas BG exhibited individual collagen fibrils interlaced to form coarse collagen strands. In enzyme resistance and tensile strength tests, DHT and DHT/EDC membranes demonstrated good resistance and mechanical properties compared with BG. In vivo, all three membranes were well integrated into the surrounding connective tissue. Thus, the DHT membrane exhibited its potential as a barrier membrane for guided bone and tissue regeneration.

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...

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 ...

[Clinic significance of nm23, collage IV and PCNA expression in non-small cell lung cancer].

Science.gov (United States)

Yu, Q; Ma, L; Jing, S; Xu, Y; Geng, D

2001-12-20

To study the significance of nm23, collagen IV and PCNA expressions in non-small cell lung cancer. Expressions of the nm23, collagen IV and PCNA in 84 cases of non-small cell lung cancer were examined with SP immunohistochemical technique. Of the 84 cases, there were squamous cell carcinoma 42, adenocarcinoma 42, stage I 27, stage II 24, stage III 24, and stage IV 9. Statistical analysis was performed with Chi-Square test. Expressions of the nm23, collagen IV and PCNA in 84 cases of non-small cell lung cancer were 60. 7% ( 51/ 84) , 75. 0% ( 63/ 84) and 53. 6% ( 45/ 84) respectively. There was negative correlation between the lymph node metastasis and the expressions of nm23 and collagen IV in squamous cell carcinoma, and the expressions of collagen IV and PCNA were associated with tumor differentiation. No correlation was found between TNM stage and expressions of nm23, collagen IV and PCNA. The results indicate that nm23, collagen IV and PCNA participate the modulation of metastasis of non-small cell lung cancer and that they may be used to evaluate the potential of metastasis.

Effect of controlled release of brain-derived neurotrophic factor and neurotrophin-3 from collagen gel on neural stem cells.

Science.gov (United States)

Huang, Fei; Wu, Yunfeng; Wang, Hao; Chang, Jun; Ma, Guangwen; Yin, Zongsheng

2016-01-20

This study aimed to examine the effect of controlled release of brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) from collagen gel on rat neural stem cells (NSCs). With three groups of collagen gel, BDNF/collagen gel, and NT-3/collagen gel as controls, BDNF and NT-3 were tested in the BDNF-NT-3/collagen gel group at different time points. The enzyme-linked immunosorbent assay results showed that BDNF and NT-3 were steadily released from collagen gels for 10 days. The cell viability test and the bromodeoxyuridine incorporation assay showed that BDNF-NT-3/collagen gel supported the survival and proliferation of NSCs. The results also showed that the length of processes was markedly longer and differentiation percentage from NSCs into neurons was much higher in the BDNF-NT-3/collagen gel group than those in the collagen gel, BDNF/collagen gel, and NT-3/collagen gel groups. These findings suggest that BDNF-NT-3/collagen gel could significantly improve the ability of NSCs proliferation and differentiation.

Complete amino acid sequence of the human alpha 5 (IV) collagen chain and identification of a single-base mutation in exon 23 converting glycine 521 in the collagenous domain to cysteine in an Alport syndrome patient

DEFF Research Database (Denmark)

Zhou, J; Hertz, Jens Michael; Leinonen, A

1992-01-01

We have generated and characterized cDNA clones providing the complete amino acid sequence of the human type IV collagen chain whose gene has been shown to be mutated in X chromosome-linked Alport syndrome. The entire translation product has 1,685 amino acid residues. There is a 26-residue signal...

Identification of type IV collagen exposure as a molecular imaging target for early detection of thoracic aortic dissection

Science.gov (United States)

Xu, Ke; Xu, Chen; Zhang, Yanzhenzi; Qi, Feiran; Yu, Bingran; Li, Ping; Jia, Lixin; Li, Yulin; Xu, Fu-jian; Du, Jie

2018-01-01

Thoracic aortic dissection (TAD) is an aggressive and life-threatening vascular disease and there is no effective means of early diagnosis of dissection. Type IV collagen (Col-IV) is a major component of the sub-endothelial basement membrane, which is initially exposed followed by endothelial injury as early-stage event of TAD. So, we want to build a noninvasive diagnostic method to detect early dissection by identifying the exposed Col-IV via MRI. Methods: Col-IV-targeted magnetic resonance/ fluorescence dual probe (Col-IV-DOTA-Gd-rhodamine B; CDR) was synthesized by amide reaction and coordination reaction. Flow cytometry analysis was used to evaluate the cell viability of SMC treated with CDR and fluorescence assays were used to assess the Col-IV targeting ability of CDR in vitro. We then examined the sensitivity and specificity of CDR at different stages of TAD via MRI and bioluminescence imaging in vivo. Results: The localization of Col-IV (under the intima) was observed by histology images. CDR bound specifically to Col-IV-expressing vascular smooth muscle cells and BAPN-induced dissected aorta. The CDR signal was co-detected by magnetic resonance imaging (MRI) and bioluminescence imaging as early as 2 weeks after BAPN administration (pre-dissection stage). The ability to detect rupture of dissected aorta was indicated by a strong normalized signal enhancement (NSE) in vivo. Moreover, NSE was negatively correlated with the time of dissection rupture after BAPN administration (r2 = 0.8482). Conclusion: As confirmed by in vivo studies, the CDR can identify the exposed Col-IV in degenerated aorta to monitor the progress of aortic dissection from the early stage to the rupture via MRI. Thus, CDR-enhanced MRI proposes a potential method for dissection screening, and for monitoring disease progression and therapeutic response. PMID:29290819

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

Clinical value of the joint measurement of serum concentrations of type IV collagen and laminin in patients with diabetic nephropathy

International Nuclear Information System (INIS)

Wang Lu; Wang Ping; Li Yongpei

2004-01-01

Objective: To study clinical value of the joint measurement of serum concentrations of type IV collagen (IV C) and laminin (LN) in patients with diabetic nephropathy (DN) by radioimmunoassay (RIA). Methods: Serum concentrations of IV C, LN were measured by RIA in 35 diabetic patients with normalbuminuria (group A), 28 cases of microalbuminuria (group B), 15 cases of macroalbuminuria (group C) and 30 normal subjects as control . Results: The serum concentrations of IV C, LN in total 78 diabetic patients [(97.6 ± 19.2), (132.4 ± 31.5) μg/L] were higher than that of the controls [(77.4 ± 8.2), (101.5 ± 17.6) μg/L, P<0.05], especially in group B and C, it was remarkably higher compared with the controls (P<0.05, P<0.01). There was significant positive correlation of serum IV C, LN to diabetic duration and the levels of blood urea nitrogen (BUN), creatinine (Cr), urinary albumin excretion rate (UAER). Conclusions: The results suggest that the joint measurement of serum levels of IV C, LN and UAER in DN patients might better evaluate the development process of DN, and be of help for early diagnosis and treatment of DN. Serum levels of IV C, LN and UAER in DN patients may become the reliable clinical markers for assessing the severity and predicting the prognosis of DN

Influence of collagen type II and nucleus pulposus cells on aggregation and differentiation of adipose tissue-derived stem cells

NARCIS (Netherlands)

Lu, Z.F.; Zandieh Doulabi, B.; Wuisman, P.I.; Bank, R.A.; Helder, M.N.

2008-01-01

Tissue microenvironment plays a critical role in guiding local stem cell differentiation. Within the intervertebral disc, collagen type II and nucleus pulposus (NP) cells are two major components. This study aimed to investigate how collagen type II and NP cells affect adipose tissue-derived stem

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.

H-ras oncogene-transformed human bronchial epithelial cells (TBE-1) secrete a single metalloprotease capable of degrading basement membrane collagen

International Nuclear Information System (INIS)

Collier, I.E.; Wilhelm, S.M.; Eisen, A.Z.

1988-01-01

H-ras transformed human bronchial epithelial cells (TBE-1) secrete a single major extracellular matrix metalloprotease which is not found in the normal parental cells. The enzyme is secreted in a latent form which can be activated to catalyze the cleavage of the basement membrane macromolecule type IV collagen. The substrates in their order of preference are: gelatin, type IV collagen, type V collagen, fibronectin, and type VII collagen; but the enzyme does not cleave the interstitial collagens or laminin. This protease is identical to gelatinase isolated from normal human skin explants, normal human skin fibroblasts, and SV40-transformed human lung fibroblasts. Based on this ability to initiate the degradation of type IV collagen in a pepsin-resistant portion of the molecule, it will be referred to as type IV collagenase. This enzyme is most likely the human analog of type IV collagenase detected in several rodent tumors. Type IV collagenase consists of three domains. Type IV collagenase represents the third member of a newly recognized gene family coding for secreted extracellular matrix metalloproteases, which includes interstitial fibroblast collagenase and stromelysin

Inhibitory assay for degradation of collagen IV by cathepsin B with a surface plasmon resonance sensor.

Science.gov (United States)

Shoji, Atsushi; Suenaga, Yumiko; Hosaka, Atsushi; Ishida, Yuuki; Yanagida, Akio; Sugawara, Masao

2017-10-25

We describe a simple method for evaluating the inhibition of collagen IV degradation by cathepsin B with a surface plasmon resonance (SPR) biosensor. The change in the SPR signal decreased with an increase in the concentration of cathepsin B inhibitors. The order of the inhibitory constant (Ki) obtained by the SPR method was CA074Me≈Z-Phe-Phe-FMK < leupeptin. This order was different from that obtained by benzyloxycarbonyl-Phe-Phe-Fluoromethylketone (Z-Phe-Phe-FMK) as a peptide substrate. The comparison of Ki suggested that CA074 and Z-Phe-Phe-FMK inhibited exopeptidase activity, and leupeptin inhibited the endopeptidase activity of cathepsin B more strongly. Copyright © 2017 Elsevier B.V. All rights reserved.

The effects of impact and non-impact exercise on circulating markers of collagen remodelling in humans

DEFF Research Database (Denmark)

Mackey, Abigail; Donnelly, Alan E; Swanton, Alan

2006-01-01

running session. Blood samples were collected before exercise and on days 1, 2, 3, 6 and 10 after exercise for measurement of creatine kinase activity, type IV collagen antigenicity, and concentrations of matrix metalloproteinase (MMP)- 9, tissue inhibitors of metalloproteinase (TIMP)- 1 and -2......, and the MMP-2/TIMP-2 complex. Serum creatine kinase was elevated 24 h after the road run, but unchanged after the deep water running session. Serum collagen IV antigenicity decreased after both the road run and the deep water running session, suggesting suppressed type IV collagen synthesis in response...... to exercise, although serum MMPs and TIMPs remained unchanged after exercise. These results suggest that collagen IV synthesis is temporarily suppressed after exercise, irrespective of exercise type....

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

Partial characterization of a low molecular weight human collagen that undergoes alternative splicing

International Nuclear Information System (INIS)

Pihlajaniemi, T.; Myllylea, R.; Kurkinen, M.; Prockop, D.J.

1987-01-01

A cDNA library prepared from RNA isolated from a cultured human tumor cell line, HT-1080, was screened with a mouse cDNA clone coding for part of the -Gly-Xaa-Yaa-domain of the α2(IV) collagen chain. Four overlapping cDNA clones were characterized that coded for a low molecular weight human collagen. The cDNA clones did not, however, code for the short-chain collagens, types IX and X. The amino acid sequences derived from the clones resembled type IV collagen in that there were short interruptions in the repeating -Gly-Xaa-Yaa-sequence. The noncollagenous, carboxyl-terminal domain was, however, much shorter and contained only 18 amino acid residues. Interestingly, one of the cDNA clones contained an additional 36 nucleotides not found in an overlapping clone. The 36 nucleotides encoded four -Gly-Xaa-Yaa-repeats without changing the reading frame. Nuclease S1 mapping using a 32 P-labelled probe demonstrated that the different between the clones was due to existence of two different mRNAs. A synthetic 24-residue peptide corresponding to the last two -Gly-Xaa-Yaa-triplets and the entire carboxyl-terminal domain was used to generate polyclonal antibodies. Electrophoretic transfer blot analysis of HT-1080 cells and normal human skin fibroblasts identified two polypeptides, M/sub r/ 67,000 and M/sub r/ 62,000, that were sensitive to bacterial collagenase

One-step derivation of mesenchymal stem cell (MSC-like cells from human pluripotent stem cells on a fibrillar collagen coating.

Directory of Open Access Journals (Sweden)

Yongxing Liu

Full Text Available Controlled differentiation of human embryonic stem cells (hESCs and induced pluripotent stem cells (iPSCs into cells that resemble adult mesenchymal stem cells (MSCs is an attractive approach to obtain a readily available source of progenitor cells for tissue engineering. The present study reports a new method to rapidly derive MSC-like cells from hESCs and hiPSCs, in one step, based on culturing the cells on thin, fibrillar, type I collagen coatings that mimic the structure of physiological collagen. Human H9 ESCs and HDFa-YK26 iPSCs were singly dissociated in the presence of ROCK inhibitor Y-27632, plated onto fibrillar collagen coated plates and cultured in alpha minimum essential medium (alpha-MEM supplemented with 10% fetal bovine serum, 50 uM magnesium L-ascorbic acid phosphate and 100 nM dexamethasone. While fewer cells attached on the collagen surface initially than standard tissue culture plastic, after culturing for 10 days, resilient colonies of homogenous spindle-shaped cells were obtained. Flow cytometric analysis showed that a high percentage of the derived cells expressed typical MSC surface markers including CD73, CD90, CD105, CD146 and CD166 and were negative as expected for hematopoietic markers CD34 and CD45. The MSC-like cells derived from pluripotent cells were successfully differentiated in vitro into three different lineages: osteogenic, chondrogenic, and adipogenic. Both H9 hES and YK26 iPS cells displayed similar morphological changes during the derivation process and yielded MSC-like cells with similar properties. In conclusion, this study demonstrates that bioimimetic, fibrillar, type I collagen coatings applied to cell culture plates can be used to guide a rapid, efficient derivation of MSC-like cells from both human ES and iPS cells.

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.

Colonization of collagen scaffolds by adipocytes derived from mesenchymal stem cells of the common marmoset monkey

International Nuclear Information System (INIS)

Bernemann, Inga; Mueller, Thomas; Blasczyk, Rainer; Glasmacher, Birgit; Hofmann, Nicola

2011-01-01

Highlights: → Marmoset bone marrow-derived MSCs differentiate in suspension into adipogenic, osteogenic and chondrogenic lineages. → Marmoset MSCs integrate in collagen type I scaffolds and differentiate excellently into adipogenic cells. → Common marmoset monkey is a suitable model for soft tissue engineering in human regenerative medicine. -- Abstract: In regenerative medicine, human cell replacement therapy offers great potential, especially by cell types differentiated from immunologically and ethically unproblematic mesenchymal stem cells (MSCs). In terms of an appropriate carrier material, collagen scaffolds with homogeneous pore size of 65 μm were optimal for cell seeding and cultivating. However, before clinical application and transplantation of MSC-derived cells in scaffolds, the safety and efficiency, but also possible interference in differentiation due to the material must be preclinically tested. The common marmoset monkey (Callithrix jacchus) is a preferable non-human primate animal model for this aim due to its genetic and physiological similarities to the human. Marmoset bone marrow-derived MSCs were successfully isolated, cultured and differentiated in suspension into adipogenic, osteogenic and chondrogenic lineages by defined factors. The differentiation capability could be determined by FACS. Specific marker genes for all three cell types could be detected by RT-PCR. Furthermore, MSCs seeded on collagen I scaffolds differentiated in adipogenic lineage showed after 28 days of differentiation high cell viability and homogenous distribution on the material which was validated by calcein AM and EthD staining. As proof of adipogenic cells, the intracellular lipid vesicles in the cells were stained with Oil Red O. The generation of fat vacuoles was visibly extensive distinguishable and furthermore determined on the molecular level by expression of specific marker genes. The results of the study proved both the differential potential of marmoset

Colonization of collagen scaffolds by adipocytes derived from mesenchymal stem cells of the common marmoset monkey

Energy Technology Data Exchange (ETDEWEB)

Bernemann, Inga, E-mail: bernemann@imp.uni-hannover.de [Institute for Multiphase Processes, Leibniz Universitaet Hannover, Hannover (Germany); Mueller, Thomas; Blasczyk, Rainer [Institute for Transfusion Medicine, Hannover Medical School, Hannover (Germany); Glasmacher, Birgit; Hofmann, Nicola [Institute for Multiphase Processes, Leibniz Universitaet Hannover, Hannover (Germany)

2011-07-29

Highlights: {yields} Marmoset bone marrow-derived MSCs differentiate in suspension into adipogenic, osteogenic and chondrogenic lineages. {yields} Marmoset MSCs integrate in collagen type I scaffolds and differentiate excellently into adipogenic cells. {yields} Common marmoset monkey is a suitable model for soft tissue engineering in human regenerative medicine. -- Abstract: In regenerative medicine, human cell replacement therapy offers great potential, especially by cell types differentiated from immunologically and ethically unproblematic mesenchymal stem cells (MSCs). In terms of an appropriate carrier material, collagen scaffolds with homogeneous pore size of 65 {mu}m were optimal for cell seeding and cultivating. However, before clinical application and transplantation of MSC-derived cells in scaffolds, the safety and efficiency, but also possible interference in differentiation due to the material must be preclinically tested. The common marmoset monkey (Callithrix jacchus) is a preferable non-human primate animal model for this aim due to its genetic and physiological similarities to the human. Marmoset bone marrow-derived MSCs were successfully isolated, cultured and differentiated in suspension into adipogenic, osteogenic and chondrogenic lineages by defined factors. The differentiation capability could be determined by FACS. Specific marker genes for all three cell types could be detected by RT-PCR. Furthermore, MSCs seeded on collagen I scaffolds differentiated in adipogenic lineage showed after 28 days of differentiation high cell viability and homogenous distribution on the material which was validated by calcein AM and EthD staining. As proof of adipogenic cells, the intracellular lipid vesicles in the cells were stained with Oil Red O. The generation of fat vacuoles was visibly extensive distinguishable and furthermore determined on the molecular level by expression of specific marker genes. The results of the study proved both the differential

Basement Membrane Type IV Collagen and Laminin: An Overview of Their Biology and Value as Fibrosis Biomarkers of Liver Disease.

Science.gov (United States)

Mak, Ki M; Mei, Rena

2017-08-01

Basement membranes provide structural support to epithelium, endothelium, muscles, fat cells, Schwann cells, and axons. Basement membranes are multifunctional: they modulate cellular behavior, regulate organogenesis, promote tissue repair, form a barrier to filtration and tumor metastasis, bind growth factors, and mediate angiogenesis. All basement membranes contain type IV collagen (Col IV), laminin, nidogen, and perlecan. Col IV and laminin self-assemble into two independent supramolecular networks that are linked to nidogen and perlecan to form a morphological discernable basement membrane/basal lamina. The triple helical region, 7S domain and NCI domain of Col IV, laminin and laminin fragment P1 have been evaluated as noninvasive fibrosis biomarkers of alcoholic liver disease, viral hepatitis, and nonalcoholic fatty liver disease. Elevated serum Col IV and laminin are related to degrees of fibrosis and severity of hepatitis, and may reflect hepatic basement membrane metabolism. But the serum assays have not been linked to disclosing the anatomical sites and lobular distribution of perisinusoidal basement membrane formation in the liver. Hepatic sinusoids normally lack a basement membrane, although Col IV is a normal matrix component of the space of Disse. In liver disease, laminin deposits in the space of Disse and codistributes with Col IV, forming a perisinusoidal basement membrane. Concomitantly, the sinusoidal endothelium loses its fenestrae and is transformed into vascular type endothelium. These changes lead to capillarization of hepatic sinusoids, a significant pathology that impairs hepatic function. Accordingly, codistribution of Col IV and laminin serves as histochemical marker of perisinusoidal basement membrane formation in liver disease. Anat Rec, 300:1371-1390, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

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...

Synthesis and spectroscopic studies of mono- and dicyclopentadienyl titanium (IV)/zirconium (IV) derivatives with S-alkyl-β-N-(acetylferrocenyl) methylene dithiocarbazates

International Nuclear Information System (INIS)

Srivastava, B.K.; Srivastava, S.K.; Pandey, O.P.; Sengupta, S.K.

1996-01-01

The reactions of dicyclopentadienyl titanium (IV)/zirconium (IV) dichloride and monocyclopentadienyl titanium (IV) trichloride with thio-Schiff bases (LH), derived by the condensation of S-methyl/ethyl/propyl dithiocarbazic acid and acetylferrocene have been carried out under inert atmosphere and anhydrous conditions in different stoichiometric ratios. Complexes of the types Cp 2 M(L)Cl, CpM(L) 2 Cl (M= Ti(IV) or Zr(IV)), CpTi(L)Cl 2 , CpTi(L) 2 Cl are synthesised and characterized by elemental analysis, electrical conductance, magnetic moment and spectral (electronic, infrared, 1 H NMR) data. (author). 12 refs., 1 tab

Mutation in the alpha 5(IV) collagen chain in juvenile-onset Alport syndrome without hearing loss or ocular lesions

DEFF Research Database (Denmark)

Zhou, J; Hertz, Jens Michael; Tryggvason, K

1992-01-01

A single base mutation was identified in the type IV collagen alpha 5 chain gene (COL4A5) of a Danish kindred with Alport syndrome. The 27-year-old male proband developed hematuria in childhood and terminal renal failure at the age of 25 years. He has no hearing loss or ocular lesions. Electron...... microscopy demonstrated splitting of the lamina densa of the glomerular basement membrane. The proband's mother has had persistent microscopic hematuria since the age of 40 years, but no other manifestations. Southern analysis of MspI-digested genomic DNA from the proband showed the absence of 1.3-kb and 0...

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...

Inhibition of microRNA-214-5p promotes cell survival and extracellular matrix formation by targeting collagen type IV alpha 1 in osteoblastic MC3T3-E1 cells.

Science.gov (United States)

Li, Q S; Meng, F Y; Zhao, Y H; Jin, C L; Tian, J; Yi, X J

2017-08-01

This study aimed to investigate the functional effects of microRNA (miR)-214-5p on osteoblastic cells, which might provide a potential role of miR-214-5p in bone fracture healing. Blood samples were obtained from patients with hand fracture or intra-articular calcaneal fracture and from healthy controls (HCs). Expression of miR-214-5p was monitored by qRT-PCR at day 7, 14 and 21 post-surgery. Mouse osteoblastic MC3T3-E1 cells were transfected with antisense oligonucleotides (ASO)-miR-214-5p, collagen type IV alpha 1 (COL4A1) vector or their controls; thereafter, cell viability, apoptotic rate, and the expression of collagen type I alpha 1 (COL1A1), type II collagen (COL-II), and type X collagen (COL-X) were determined. Luciferase reporter assay, qRT-PCR, and Western blot were performed to ascertain whether COL4A1 was a target of miR-214-5p. Plasma miR-214-5p was highly expressed in patients with bone fracture compared with HCs after fracture (p extracellular matrix (ECM) formation of osteoblastic MC3T3-E1 cells by targeting COL4A1. Cite this article: Q. S. Li, F. Y. Meng, Y. H. Zhao, C. L. Jin, J. Tian, X. J. Yi. Inhibition of microRNA-214-5p promotes cell survival and extracellular matrix formation by targeting collagen type IV alpha 1 in osteoblastic MC3T3-E1 cells. Bone Joint Res 2017;6:464-471. DOI: 10.1302/2046-3758.68.BJR-2016-0208.R2. © 2017 Yi et al.

Bioengineering vascularized tissue constructs using an injectable cell-laden enzymatically crosslinked collagen hydrogel derived from dermal extracellular matrix.

Science.gov (United States)

Kuo, Kuan-Chih; Lin, Ruei-Zeng; Tien, Han-Wen; Wu, Pei-Yun; Li, Yen-Cheng; Melero-Martin, Juan M; Chen, Ying-Chieh

2015-11-01

Tissue engineering promises to restore or replace diseased or damaged tissue by creating functional and transplantable artificial tissues. The development of artificial tissues with large dimensions that exceed the diffusion limitation will require nutrients and oxygen to be delivered via perfusion instead of diffusion alone over a short time period. One approach to perfusion is to vascularize engineered tissues, creating a de novo three-dimensional (3D) microvascular network within the tissue construct. This significantly shortens the time of in vivo anastomosis, perfusion and graft integration with the host. In this study, we aimed to develop injectable allogeneic collagen-phenolic hydroxyl (collagen-Ph) hydrogels that are capable of controlling a wide range of physicochemical properties, including stiffness, water absorption and degradability. We tested whether collagen-Ph hydrogels could support the formation of vascularized engineered tissue graft by human blood-derived endothelial colony-forming cells (ECFCs) and bone marrow-derived mesenchymal stem cells (MSC) in vivo. First, we studied the growth of adherent ECFCs and MSCs on or in the hydrogels. To examine the potential formation of functional vascular networks in vivo, a liquid pre-polymer solution of collagen-Ph containing human ECFCs and MSCs, horseradish peroxidase and hydrogen peroxide was injected into the subcutaneous space or abdominal muscle defect of an immunodeficient mouse before gelation, to form a 3D cell-laden polymerized construct. These results showed that extensive human ECFC-lined vascular networks can be generated within 7 days, the engineered vascular density inside collagen-Ph hydrogel constructs can be manipulated through refinable mechanical properties and proteolytic degradability, and these networks can form functional anastomoses with the existing vasculature to further support the survival of host muscle tissues. Finally, optimized conditions of the cell-laden collagen

Study on reduction and back extraction of Pu(IV) by urea derivatives in nitric acid conditions

International Nuclear Information System (INIS)

Ye, G.A.; Xiao, S.T.; Yan, T.H.; Lin, R.S.; Zhu, Z.W.

2013-01-01

The reduction kinetics of Pu(IV) by hydroxyl-semicarbazide (HSC), hydroxyurea (HU) and di-hydroxyurea (DHU) in nitric acid solutions were investigated separately with adequate kinetic equations. In addition, counter-current cascade experiments were conducted for Pu split from U in nitric acid media using three kinds of reductant, respectively. The results show that urea derivatives as a kind of novel salt-free reductant can reduce Pu(IV) to Pu(III) rapidly in the nitric acid solutions. The stripping experimental results showed that Pu(IV) in the organic phase can be stripped rapidly to the aqueous phase by the urea derivatives, and the separation factors of plutonium /uranium can reach more than 10 4 . This indicates that urea derivatives is a kind of promising salt-free agent for uranium/plutonium separation. In addition, the complexing effect of HSC with Np(IV) was revealed, and Np(IV) can be back-extracted by HSC with a separation factor of about 20

Study on reduction and back extraction of Pu(IV) by urea derivatives in nitric acid conditions

Energy Technology Data Exchange (ETDEWEB)

Ye, G.A.; Xiao, S.T.; Yan, T.H.; Lin, R.S.; Zhu, Z.W. [China Institute of Atomic Energy, P.O.Box 275(26), Beijing 102413 (China)

2013-07-01

The reduction kinetics of Pu(IV) by hydroxyl-semicarbazide (HSC), hydroxyurea (HU) and di-hydroxyurea (DHU) in nitric acid solutions were investigated separately with adequate kinetic equations. In addition, counter-current cascade experiments were conducted for Pu split from U in nitric acid media using three kinds of reductant, respectively. The results show that urea derivatives as a kind of novel salt-free reductant can reduce Pu(IV) to Pu(III) rapidly in the nitric acid solutions. The stripping experimental results showed that Pu(IV) in the organic phase can be stripped rapidly to the aqueous phase by the urea derivatives, and the separation factors of plutonium /uranium can reach more than 10{sup 4}. This indicates that urea derivatives is a kind of promising salt-free agent for uranium/plutonium separation. In addition, the complexing effect of HSC with Np(IV) was revealed, and Np(IV) can be back-extracted by HSC with a separation factor of about 20.

Synthesis and characterization of ester and amide derivatives of titanium(IV) carboxymethylphosphonate

International Nuclear Information System (INIS)

Melánová, Klára; Beneš, Ludvík; Trchová, Miroslava; Svoboda, Jan; Zima, Vítězslav

2013-01-01

A set of layered ester and amide derivatives of titanium(IV) carboxymethylphosphonate was prepared by solvothermal treatment of amorphous titanium(IV) carboxymethylphosphonate with corresponding 1-alkanols, 1,ω-alkanediols, 1-aminoalkanes, 1,ω-diaminoalkanes and 1,ω-amino alcohols and characterized by powder X-ray diffraction, IR spectroscopy and thermogravimetric analysis. Whereas alkyl chains with one functional group form bilayers tilted to the layers, 1,ω-diaminoalkanes and most of 1,ω-alkanediols form bridges connecting the adjacent layers. In the case of amino alcohols, the alkyl chains form bilayer and either hydroxyl or amino group is used for bonding. This simple method for the synthesis of ester and amide derivatives does not require preparation of acid chloride derivative as a precursor or pre-intercalation with alkylamines and can be used also for the preparation of ester and amide derivatives of titanium carboxyethylphosphonate and zirconium carboxymethylphosphonate. - Graphical abstract: Ester and amide derivatives of layered titanium carboxymethylphosphonate were prepared by solvothermal treatment of amorphous solid with alkanol or alkylamine. - Highlights: • Ester and amide derivatives of titanium carboxymethylphosphonate. • Solvothermal treatment of amorphous solid with alkanol or alkylamine. • Ester and amide formation confirmed by IR spectroscopy

Carboxylate derivatives of tributyltin (IV) complexes as anticancer and antileishmanial agents.

Science.gov (United States)

Waseem, Durdana; Butt, Arshad Farooq; Haq, Ihsan-Ul; Bhatti, Moazzam Hussain; Khan, Gul Majid

2017-04-04

Tributyltin (IV) compounds are promising candidates for drug development. In the current study, we evaluated in-vitro and in-silico profile of carboxylate derivatives of tributyltin (IV) complexes. ADMET and drug-likeliness properties were predicted using MetaPrint2D React, preADMET, SwissADME and Molsoft tools. SwissTargetPrediction predicted molecular targets for compounds. In-vitro bioactivity was evaluated by quantifying cytotoxicity against HepG2, THP-1 cell lines, isolated lymphocytes and leishmania promastigotes as well as measuring protein kinase (PK) inhibition activity. Results indicate partial compliance of compounds with drug-likeliness rules. Ch-409 complies with WDI and Lipinski rules. ADMET profile prediction shows strong plasma protein binding except for Ch-409, low to high GI absorption and BBB penetration (C brain /C blood  = 0.942-11; caco-2 cells permeability 20.13-26.75 nm/sec), potential efflux by P-glycoprotein, metabolism by CYP3A4, medium inhibition of hERG, mutagenicity and capacity to be detoxified by glutathionation and glucuronidation. Molecular targets include proteases, enzymes, membrane receptors, transporters and ion channels where Ch-409 targets membrane receptors only. Compounds are significantly (p tributyltin (IV) complexes possess significant antileishmanial and cytotoxic potential. These are promising compounds for the development of antileishmanial and anticancer drugs. Graphical Abstract Carboxylate derivatives of tributyltin (IV) complexes as anticancer and antileishmanial agents.

AUTOLOGOUS Marrow-Derived Stem Cell-Seeded Gene-Supplemented Collagen Scaffolds for Spinal Cord Regeneration as a Treatment for Paralysis

National Research Council Canada - National Science Library

Spector, Myron

2006-01-01

.... Moreover, the authors will be investigating the effects of incorporating genes from nerve growth factors into the collagen scaffolds and seeding the scaffolds with marrow-derived mesenchymal stem cells...

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.

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...

Determination of osteogenic or adipogenic lineages in muscle-derived stem cells (MDSCs) by a collagen-binding peptide (CBP) derived from bone sialoprotein (BSP)

Energy Technology Data Exchange (ETDEWEB)

Choi, Yoon Jung [Dental Regenerative Biotechnology Major, School of Dentistry and Dental Research Institute, Seoul National University, Seoul 110-749 (Korea, Republic of); Lee, Jue Yeon [Research Institute, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of); Lee, Seung Jin [Department of Industrial Pharmacy, College of Pharmacy, Ewha Womans University, Seoul (Korea, Republic of); Chung, Chong-Pyoung, E-mail: ccpperio@snu.ac.kr [Research Institute, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of); Department of Periodontology, School of Dentistry and Dental Research Institute, Seoul National University, Seoul (Korea, Republic of); Park, Yoon Jeong, E-mail: parkyj@snu.ac.kr [Dental Regenerative Biotechnology Major, School of Dentistry and Dental Research Institute, Seoul National University, Seoul 110-749 (Korea, Republic of); Research Institute, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of)

2012-03-09

Highlights: Black-Right-Pointing-Pointer CBP sequence is identified from BSP and has collagen binding activity. Black-Right-Pointing-Pointer CBP directly activates the MAPK signaling, especially ERK1/2. Black-Right-Pointing-Pointer CBP increase osteoblastic differentiation by the activation of Runx2. Black-Right-Pointing-Pointer CBP decrease adipogenic differentiation by the inhibition of PPAR{gamma}. -- Abstract: Bone sialoprotein (BSP) is a mineralized, tissue-specific, non-collagenous protein that is normally expressed only in mineralized tissues such as bone, dentin, cementum, and calcified cartilage, and at sites of new mineral formation. The binding of BSP to collagen is thought to be important for initiating bone mineralization and bone cell adhesion to the mineralized matrix. Several recent studies have isolated stem cells from muscle tissue, but their functional properties are still unclear. In this study, we examined the effects of a synthetic collagen-binding peptide (CBP) on the differentiation efficiency of muscle-derived stem cells (MDSCs). The CBP sequence (NGVFKYRPRYYLYKHAYFYPHLKRFPVQ) corresponds to residues 35-62 of bone sialoprotein (BSP), which are located within the collagen-binding domain in BSP. Interestingly, this synthetic CBP inhibited adipogenic differentiation but increased osteogenic differentiation in MDSCs. The CBP also induced expression of osteoblastic marker proteins, including alkaline phosphatase (ALP), type I collagen, Runt-related transcription factor 2 (Runx2), and osteocalcin; prevented adipogenic differentiation in MDSCs; and down-regulated adipose-specific mRNAs, such as adipocyte protein 2 (aP2) and peroxisome proliferator-activated receptor {gamma}. The CBP increased Extracellular signal-regulated kinases (ERK) 1/2 protein phosphorylation, which is important in lineage determination. These observations suggest that this CBP determines the osteogenic or adipogenic lineage in MDSCs by activating ERK1/2. Taken together, a

Bone Healing in Extraction Sockets Covered With Collagen Membrane Alone or Associated With Porcine-Derived Bone Graft: a Comparative Histological and Histomorphometric Analysis.

Science.gov (United States)

Guarnieri, Renzo; Testarelli, Luca; Stefanelli, Luigi; De Angelis, Francesca; Mencio, Francesca; Pompa, Giorgio; Di Carlo, Stefano

2017-01-01

The present paper reports data of a randomized study aimed to analyse and compare the histologic and histomorphometric aspects of bone healing in extraction sites covered with collagen membrane alone or associated with porcine-derived bone graft. Thirty patients, with single extraction sockets without severe bone wall defects in the premolar/molar region, were included. Ten extraction sockets were grafted with porcine-derived bone and covered with collagen membrane (group 1), 10 sites were covered with collagen membrane alone (group 2), and 10 sites healed spontaneously (group 3). After 4 months of healing, 26 (8 in group 1, 9 in group 2, and 9 in group 3) bone core specimens were harvested for histologic evaluation, then dental implants were placed. Sites in the group 1 and in the group 2 showed similar histologic and histomorphometric results without significantly differences in the percentage of vital bone (57.43% [SD 4.8] vs. 60.01% [SD 3.2]), and non-mineralized connective tissue 22.99% (SD 5.3) vs. 18.53% (SD 6.2). In group 1 a 16.57% (SD 3.8) of residual material was found. Results showed that the use of collagen membrane alone or associated to porcine-derived bone improves the healing bone process compared to that of extraction sites spontaneously healed. Moreover, histomorphometric data related to bone quality, indicated that extraction sites without severe walls defects and with a vestibular bone thickness > 1.5 mm, treated with a low resorbtion rate collagen membrane alone, do not need more than 4 months for dental implant insertion.

In Vitro Expression of the Extracellular Matrix Components Aggrecan, Collagen Types I and II by Articular Cartilage-Derived Chondrocytes.

Science.gov (United States)

Schneevoigt, J; Fabian, C; Leovsky, C; Seeger, J; Bahramsoltani, M

2017-02-01

The extracellular matrix (ECM) of hyaline cartilage is perfectly suited to transmit articular pressure load to the subchondral bone. Pressure is transferred by a high amount of aggrecan-based proteoglycans and collagen type II fibres in particular. After any injury, the hyaline cartilage is replaced by fibrocartilage, which is low in proteoglycans and contains collagen type I predominantly. Until now, long-term results of therapeutic procedures including cell-based therapies like autologous chondrocyte transplantation (ACT) lead to a replacement tissue meeting the composition of fibrocartilage. Therefore, it is of particular interest to discover how and to what extent isolation and in vitro cultivation of chondrocytes affect the cells and their expression of ECM components. Hyaline cartilage-derived chondrocytes were cultivated in vitro and observed microscopically over a time period of 35 days. The expression of collagen type I, collagen type II and aggrecan was analysed using RT-qPCR and Western blot at several days of cultivation. Chondrocytes presented a longitudinal shape for the entire cultivation period. While expression of collagen type I prevailed within the first days, only prolonged cultivation led to an increase in collagen type II and aggrecan expression. The results indicate that chondrocyte isolation and in vitro cultivation lead to a dedifferentiation at least to the stage of chondroprogenitor cells. © 2016 Blackwell Verlag GmbH.

MCF-7 human mammary adenocarcinoma cells exhibit augmented responses to human insulin on a collagen IV surface

DEFF Research Database (Denmark)

Listov-Saabye, Nicolai; Jensen, Marianne Blirup; Kiehr, Benedicte

2009-01-01

Human mammary cell lines are extensively used for preclinical safety assessment of insulin analogs. However, it is essentially unknown how mitogenic responses can be optimized in mammary cell-based systems. We developed an insulin mitogenicity assay in MCF-7 human mammary adenocarcinoma cells......, under low serum (0.1% FCS) and phenol red-free conditions, with 3H thymidine incorporation as endpoint. Based on EC50 values determined from 10-fold dilution series, beta-estradiol was the most potent mitogen, followed by human IGF-1, human AspB10 insulin and native human insulin. AspB10 insulin...... was significantly more mitogenic than native insulin, validating the ability of the assay to identify hypermitogenic human insulin analogs. With MCF-7 cells on a collagen IV surface, the ranking of mitogens was maintained, but fold mitogenic responses and dynamic range and steepness of dose-response curves were...

Sericin Enhances the Bioperformance of Collagen-Based Matrices Preseeded with Human-Adipose Derived Stem Cells (hADSCs

Directory of Open Access Journals (Sweden)

Marieta Costache

2013-01-01

Full Text Available Current clinical strategies for adipose tissue engineering (ATE, including autologous fat implants or the use of synthetic surrogates, not only are failing in the long term, but also can’t face the latest requirements regarding the aesthetic restoration of the resulted imperfections. In this context, modern strategies in current ATE applications are based on the implantation of 3D cell-scaffold bioconstructs, designed for prospective achievement of in situ functional de novo tissue. Thus, in this paper, we reported for the first time the evaluation of a spongious 60% collagen and 40% sericin scaffold preseeded with human adipose-derived stem cells (hADSCs in terms of biocompatibility and adipogenic potential in vitro. We showed that the addition of the sticky protein sericin in the composition of a classical collagen sponge enhanced the adhesion and also the proliferation rate of the seeded cells, thus improving the biocompatibility of the novel scaffold. In addition, sericin stimulated PPARγ2 overexpression, triggering a subsequent upregulated expression profile of FAS, aP2 and perilipin adipogenic markers. These features, together with the already known sericin stimulatory potential on cellular collagen production, promote collagen-sericin biomatrix as a good candidate for soft tissue reconstruction and wound healing applications.

Proportion of collagen type II in the extracellular matrix promotes the differentiation of human adipose-derived mesenchymal stem cells into nucleus pulposus cells.

Science.gov (United States)

Tao, Yiqing; Zhou, Xiaopeng; Liu, Dongyu; Li, Hao; Liang, Chengzhen; Li, Fangcai; Chen, Qixin

2016-01-01

During degeneration process, the catabolism of collagen type II and anabolism of collagen type I in nucleus pulposus (NP) may influence the bioactivity of transplanted cells. Human adipose-derived mesenchymal stem cells (hADMSCs) were cultured as a micromass or in a series of gradual proportion hydrogels of a mix of collagen types I and II. Cell proliferation and cytotoxicity were detected using CCK-8 and LDH assays respectively. The expression of differentiation-related genes and proteins, including SOX9, aggrecan, collagen type I, and collagen type II, was examined using RT-qPCR and Western blotting. Novel phenotypic genes were also detected by RT-qPCR and western blotting. Alcian blue and dimethylmethylene blue assays were used to investigate sulfate proteoglycan expression, and PI3K/AKT, MAPK/ERK, and Smad signaling pathways were examined by Western blotting. The results showed collagen hydrogels have good biocompatibility, and cell proliferation increased after collagen type II treatment. Expressions of SOX9, aggrecan, and collagen type II were increased in a collagen type II dependent manner. Sulfate proteoglycan synthesis increased in proportion to collagen type II concentration. Only hADMSCs highly expressed NP cell marker KRT19 in collagen type II culture. Additionally, phosphorylated Smad3, which is associated with phosphorylated ERK, was increased after collagen type II-stimulation. The concentration and type of collagen affect hADMSC differentiation into NP cells. Collagen type II significantly ameliorates hADMSC differentiation into NP cells and promotes extracellular matrix synthesis. Therefore, anabolism of collagen type I and catabolism of type II may attenuate the differentiation and biosynthesis of transplanted stem cells. © 2016 International Union of Biochemistry and Molecular Biology.

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....

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....

[Effect of compound Puerarin on the collage IV in streptozotocin-induced diabetic nephropathy rats].

Science.gov (United States)

Li, Qiang-xiang; Zhong, Hui-ju; Gong, Han-ren; Zhu, Fei-yue; Wang, Lin-na; Shen, Dao-jun; Li, Guo; Wang, Cai-yun; Qin, Cheng-sheng

2008-04-01

To observe the effect of compound Puerarin on collagen IV of streptozotocin-induced diabetic rats. Diabetic nephropathy rats were induced by intraperitoneal injection of streptozotocin (STZ). Rats were allocated randomly to control group (10), diabetes model group (10), Vitamin C group (10), Puerarin group (10), vitamin C plus Puerarin group (10). The study period lasted for 12 weeks. During and after the treatment, the general state, blood glucose levels, glycosylated hemoglobin, blood urea nitrogen, serum collagen IV, blood urea nitrogen, serum creatinine, urinary albumin excretion rate of the 24-hour, and clearance rate of creatinine collagen IV protein were determined by immunohistochemistoche analysis as well as type the gene expression of collagen IV alpha 1 mRNA were determined by in situ hybridization analysis in the kidney tissue of different groups. (1) Diabetes mellitus and renal function lesion occurred in the four groups. (2) Vitamin C and Puerarin could improve the general conditions of diabetic Rats, decrease blood urea nitrogen [(8.68 +/- 0.43), (7.98 +/- 0.47) and (5.76 +/- 0.82) micromol/L, serum creatinine [(74.68 +/- 8.20), (75.52 +/- 7.98) and (58.66 +/- 6.65) mmol/L], and urinary albumin excretion rate of the 24-hour [(18.40 +/- 0.37), (17.24 +/- 0.30) and (9.97 +/- 1.27) mg/24 h x 10(-3)]; increase clearance rate of creatinine [(0.59 +/- 0.21), (0.61 +/- 0.14) and (0.69 +/- 0.32) ml/min], the expression of collage IV absorbance [(111.56 +/- 14.61), (110.78 +/- 9.69) and (95.44 +/- 9.97) ] in the diabetic Rats were significantly inhibited at the same time. The compound Puerarin might have some functions on preventing ren by inhibiting expression of type IV collagen.

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.

Clinical Usage of an Extracellular, Collagen-rich Matrix: A Case Series.

Science.gov (United States)

AbouIssa, Abdelfatah; Mari, Walid; Simman, Richard

2015-11-01

OASIS Ultra (Smith and Nephew, St. Petersburg, FL) is an extracellular, collagen-rich matrix derived from submucosa of porcine intestine. It is composed of collagen type I, glycosaminoglycan, and proteoglycans. This extracellular matrix (ECM) differs from the single layer in thickness and offers ease of handling and application. It also stimulates cell migration and structural support, provides moisture environment, decreases inflammation, and induces cell proliferation and cellular attachments. In this case series, the authors present their experience with this product in various clinical scenarios. The authors used the product in a variety of wounds with different etiologies to test the clinical outcome of the ECM. This was an observational case series with prospective review of 6 different patients with different types of wounds who received treatment with the ECM during their treatment. The product was applied on the following types of wounds: chronic venous ulcer, nonhealing Achilles tendon vasculitic wound, Marjolin's ulcer, posttraumatic wound, stage IV sacral-coccygeal pressure wound, and complicated transmetatarsal amputation of gangrenous left forefoot diabetic wound. All of these wounds healed within the expected time periods and without complications. In general, healing was achieved in 4-16 weeks using 1-12 applications of the ECM. Wounds with different etiologies were successfully treated with an extracellular, collagen-rich matrix. By replacing the lost ECM to guide cellular growth and migration, this product did ultimately hasten the healing process.

Glutaraldehyde assisted synthesis of collagen derivative modified Fe3+/TiO2 nanocomposite and their enhanced photocatalytic activity

International Nuclear Information System (INIS)

Li, Chongyi; Xue, Feng; Ding, Enyong; He, Xiaoling

2015-01-01

Graphical abstract: - Highlights: • Collagen-g-PDMC was successfully designed by grafting DMC monomers onto the collagen backbone. • Fe 3+ /TiO 2 nanospheres highly capable of responding to visible light were successfully prepared. • Collagen-g-PDMC was firmly immobilized onto the Fe 3+ /TiO 2 surface by virtue of glutaraldehyde. • CFT-3 performed the best in the photocatalytic degradation of MO solution under solar irradiation. - Abstract: A unique organic–inorganic hybrid nanocomposite was designed and synthesized by chemically anchoring the cationic collagen-based derivatives onto the surface of Fe 3+ /TiO 2 nanospheres for the significant enhancement in photocatalytic activity under the visible light irradiation. The NMR analysis suggested the successful fabrication of cationic collagen-g-PDMC as grafted materials. In addition, the chemical structures, morphologies and properties of these samples were systematically characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Raman spectrum, ultra violet–visible spectroscopy (UV–vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL). And obtained results clearly demonstrated that Fe 3+ ions diffusing into TiO 2 lattice could be responsible for slightly reducing the average diameter of nanospheres to about 125 nm, promoting phase transition from anatase to rutile to some extent and extending the light harvesting range into visible region markedly. Meanwhile, the achievement that collagen-g-PDMC molecules had been covalently immobilized onto the surface of Fe 3+ /TiO 2 nanoparticles was also well supported by the information acquired. Furthermore, the photocatalytic activities of all the as-prepared products were carefully evaluated by adopting photocatalytic decoloration of methyl orange (MO) solution under the solar direct irradiation, and the sample CFT-3 performed the best in

Peroxo complexes of molybdenum(VI), tungsten(VI), uranium(VI), zirconium(IV) and thorium(IV) ions containing tridentate Schiff bases derived from salicylaldehyde and amino acids

International Nuclear Information System (INIS)

Tarafder, M.T.H.; Khan, A.R.

1997-01-01

The synthesis of peroxo complexes of molybdenum(VI), tungsten(VI), uranium(VI), zirconium(IV), thorium(IV) and their possible oxygen transfer reactions is presented. An attempt has also been made to study the size of the metal ions and the electronic effect derived from the tridentate Schiff bases on the v 1 (O-O) mode of the complexes in their IR spectra

Early adhesive behavior of bone-marrow-derived mesenchymal stem cells on collagen electrospun fibers

Energy Technology Data Exchange (ETDEWEB)

Chan, Casey K; Liao, Susan; Lareu, Ricky R; Raghunath, Michael [Division of Bioengineering, National University of Singapore, 7 Engineering Drive 1, Singapore 117574 (Singapore); Li, Bojun; Ramakrishna, S [Nanoscience and Nanotechnology Initiative, National University of Singapore, 2 Engineering Drive 3, Singapore 117576 (Singapore); Larrick, James W, E-mail: doschanc@nus.edu.s [Panorama Research Institute, 2462 Wyandotte Street, Mountain View, CA 94043 (United States)

2009-06-15

A bioabsorbable nanofibrous scaffold was developed for early adhesion of mesenchymal stem cells (MSCs). Collagen nanofibers with diameters of 430 +- 170 nm were fabricated by electrospinning. Over 45% of the MSC population adhered to this collagen nanofiber after 30 min at room temperature. Remarkably, collagen-coated P(LLA-CL) electrospun nanofibers were almost as efficient as collagen nanofibers whereas collagen cast film did not enhance early capture when it was applied on cover slips. The adhesive efficiency could be further increased to over 20% at 20 min and over 55% at 30 min when collagen nanofibers were grafted with monoclonal antibodies recognizing CD29 or CD49a. These data demonstrate that the early adhesive behavior is highly dependent on both the surface texture and the surface chemistry of the substrate. These findings have potential applications for early capture of MSCs in an ex vivo setting under time constraints such as in a surgical setting.

Early adhesive behavior of bone-marrow-derived mesenchymal stem cells on collagen electrospun fibers

International Nuclear Information System (INIS)

Chan, Casey K; Liao, Susan; Lareu, Ricky R; Raghunath, Michael; Li, Bojun; Ramakrishna, S; Larrick, James W

2009-01-01

A bioabsorbable nanofibrous scaffold was developed for early adhesion of mesenchymal stem cells (MSCs). Collagen nanofibers with diameters of 430 ± 170 nm were fabricated by electrospinning. Over 45% of the MSC population adhered to this collagen nanofiber after 30 min at room temperature. Remarkably, collagen-coated P(LLA-CL) electrospun nanofibers were almost as efficient as collagen nanofibers whereas collagen cast film did not enhance early capture when it was applied on cover slips. The adhesive efficiency could be further increased to over 20% at 20 min and over 55% at 30 min when collagen nanofibers were grafted with monoclonal antibodies recognizing CD29 or CD49a. These data demonstrate that the early adhesive behavior is highly dependent on both the surface texture and the surface chemistry of the substrate. These findings have potential applications for early capture of MSCs in an ex vivo setting under time constraints such as in a surgical setting.

Myofibroblast Expression in Skin Wounds Is Enhanced by Collagen III Suppression

Directory of Open Access Journals (Sweden)

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.

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.

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...

Toward angiogenesis of implanted bio-artificial liver using scaffolds with type I collagen and adipose tissue-derived stem cells.

Science.gov (United States)

Lee, Jae Geun; Bak, Seon Young; Nahm, Ji Hae; Lee, Sang Woo; Min, Seon Ok; Kim, Kyung Sik

2015-05-01

Stem cell therapies for liver disease are being studied by many researchers worldwide, but scientific evidence to demonstrate the endocrinologic effects of implanted cells is insufficient, and it is unknown whether implanted cells can function as liver cells. Achieving angiogenesis, arguably the most important characteristic of the liver, is known to be quite difficult, and no practical attempts have been made to achieve this outcome. We carried out this study to observe the possibility of angiogenesis of implanted bio-artificial liver using scaffolds. This study used adipose tissue-derived stem cells that were collected from adult patients with liver diseases with conditions similar to the liver parenchyma. Specifically, microfilaments were used to create an artificial membrane and maintain the structure of an artificial organ. After scratching the stomach surface of severe combined immunocompromised (SCID) mice (n=4), artificial scaffolds with adipose tissue-derived stem cells and type I collagen were implanted. Expression levels of angiogenesis markers including vascular endothelial growth factor (VEGF), CD34, and CD105 were immunohistochemically assessed after 30 days. Grossly, the artificial scaffolds showed adhesion to the stomach and surrounding organs; however, there was no evidence of angiogenesis within the scaffolds; and VEGF, CD34, and CD105 expressions were not detected after 30 days. Although implantation of cells into artificial scaffolds did not facilitate angiogenesis, the artificial scaffolds made with type I collagen helped maintain implanted cells, and surrounding tissue reactions were rare. Our findings indicate that type I collagen artificial scaffolds can be considered as a possible implantable biomaterial.

Use of synovium-derived stromal cells and chitosan/collagen type I scaffolds for cartilage tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Gong Zhongcheng; Lin Zhaoquan [Department of Oral and Maxillofacial Surgery, First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830054 (China); Xiong Hui; Long Xing; Wei Lili; Li Jian; Wu Yang, E-mail: xinglong1957@yahoo.com.c [State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei 430079 (China)

2010-10-01

The objective was to investigate synovium-derived stromal cells (SDSCs) coupled with chitosan/collagen type I (CS/COL-I) scaffolds for cartilage engineering. CS/COL-I scaffolds were fabricated through freeze-drying and cross-linked by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide. SDSCs were isolated from synovium and cultured onto CS/COL-I scaffolds, constructs of which were incubated in serum-free chondrogenic medium with sequential application of TGF-{beta}1 and bFGF for up to 21 days and then implanted into nude mice. The physical characteristics of the scaffolds were examined. The quality of the in vitro constructs was assessed in terms of DNA content by PicoGreen assay and cartilaginous matrix by histological examination. The implants of the constructs were evaluated by histological and immunohistochemical examinations and reverse transcription PCR. Results indicated that the CS/COL-I scaffold showed porous structures, and the DNA content of SDSCs in CS/COL-I scaffolds increased at 1 week culture time. Both of the constructs in vitro and the implants were examined with positive stained GAGs histologically and the implants with positive collagen type II immunohistochemically. RT-PCR of the implants indicated that aggrecan and collagen type II expressed. It suggested that SDSCs coupled with CS/COL-I scaffolds treated sequentially with TGF-{beta}1 and bFGF in vitro were highly competent for engineered cartilage formation in vitro and in vivo.

Autologous Adipose-Derived Tissue Matrix Part I: Biologic Characteristics.

Science.gov (United States)

Schendel, Stephen A

2017-10-01

Autologous collagen is an ideal soft tissue filler and may serve as a matrix for stem cell implantation and growth. Procurement of autologous collagen has been limited, though, secondary to a sufficient source. Liposuction is a widely performed and could be a source of autologous collagen. The amount of collagen and its composition in liposuctioned fat remains unknown. The purpose of this research was to characterize an adipose-derived tissue-based product created using ultrasonic cavitation and cryo-grinding. This study evaluated the cellular and protein composition of the final product. Fat was obtained from individuals undergoing routine liposuction and was processed by a 2 step process to obtain only the connective tissue. The tissue was then evaluated by scanning electronic microscope, Western blot analysis, and flow cytometry. Liposuctioned fat was obtained from 10 individuals with an average of 298 mL per subject. After processing an average of 1 mL of collagen matrix was obtained from each 100 mL of fat. Significant viable cell markers were present in descending order for adipocytes > CD90+ > CD105+ > CD45+ > CD19+ > CD144+ > CD34+. Western blot analysis showed collagen type II, III, IV, and other proteins. Scanning electronic microscope study showed a regular pattern of cross-linked, helical collagen. Additionally, vital staing demonstrated that the cells were still viable after processing. Collagen and cells can be easily obtained from liposuctioned fat by ultrasonic separation without alteration of the overall cellular composition of the tissue. Implantation results in new collagen and cellular growth. Collagen matrix with viable cells for autologous use can be obtained from liposuctioned fat and may provide long term results. 5. © 2017 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com

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.

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...

Effect of Uniaxial Tensile Cyclic Loading Regimes on Matrix Organization and Tenogenic Differentiation of Adipose-Derived Stem Cells Encapsulated within 3D Collagen Scaffolds

Directory of Open Access Journals (Sweden)

Gayathri Subramanian

2017-01-01

Full Text Available Adipose-derived mesenchymal stem cells have become a popular cell choice for tendon repair strategies due to their relative abundance, ease of isolation, and ability to differentiate into tenocytes. In this study, we investigated the solo effect of different uniaxial tensile strains and loading frequencies on the matrix directionality and tenogenic differentiation of adipose-derived stem cells encapsulated within three-dimensional collagen scaffolds. Samples loaded at 0%, 2%, 4%, and 6% strains and 0.1 Hz and 1 Hz frequencies for 2 hours/day over a 7-day period using a custom-built uniaxial tensile strain bioreactor were characterized in terms of matrix organization, cell viability, and musculoskeletal gene expression profiles. The results displayed that the collagen fibers of the loaded samples exhibited increased matrix directionality with an increase in strain values. Gene expression analyses demonstrated that ASC-encapsulated collagen scaffolds loaded at 2% strain and 0.1 Hz frequency showed significant increases in extracellular matrix genes and tenogenic differentiation markers. Importantly, no cross-differentiation potential to osteogenic, chondrogenic, and myogenic lineages was observed at 2% strain and 0.1 Hz frequency loading condition. Thus, 2% strain and 0.1 Hz frequency were identified as the appropriate mechanical loading regime to induce tenogenic differentiation of adipose-derived stem cells cultured in a three-dimensional environment.

Effect of Uniaxial Tensile Cyclic Loading Regimes on Matrix Organization and Tenogenic Differentiation of Adipose-Derived Stem Cells Encapsulated within 3D Collagen Scaffolds.

Science.gov (United States)

Subramanian, Gayathri; Stasuk, Alexander; Elsaadany, Mostafa; Yildirim-Ayan, Eda

2017-01-01

Adipose-derived mesenchymal stem cells have become a popular cell choice for tendon repair strategies due to their relative abundance, ease of isolation, and ability to differentiate into tenocytes. In this study, we investigated the solo effect of different uniaxial tensile strains and loading frequencies on the matrix directionality and tenogenic differentiation of adipose-derived stem cells encapsulated within three-dimensional collagen scaffolds. Samples loaded at 0%, 2%, 4%, and 6% strains and 0.1 Hz and 1 Hz frequencies for 2 hours/day over a 7-day period using a custom-built uniaxial tensile strain bioreactor were characterized in terms of matrix organization, cell viability, and musculoskeletal gene expression profiles. The results displayed that the collagen fibers of the loaded samples exhibited increased matrix directionality with an increase in strain values. Gene expression analyses demonstrated that ASC-encapsulated collagen scaffolds loaded at 2% strain and 0.1 Hz frequency showed significant increases in extracellular matrix genes and tenogenic differentiation markers. Importantly, no cross-differentiation potential to osteogenic, chondrogenic, and myogenic lineages was observed at 2% strain and 0.1 Hz frequency loading condition. Thus, 2% strain and 0.1 Hz frequency were identified as the appropriate mechanical loading regime to induce tenogenic differentiation of adipose-derived stem cells cultured in a three-dimensional environment.

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

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.

Collagen gel contraction serves to rapidly distinguish epithelial- and mesenchymal-derived cells irrespective of alpha-smooth muscle actin expression

DEFF Research Database (Denmark)

Nielsen, Helga Lind; Gudjonsson, Thorarinn; Villadsen, René

2004-01-01

Mesenchymal-like cells in the stroma of breast cancer may arise as a consequence of plasticity within the epithelial compartment, also referred to as epithelial-mesenchymal transition, or by recruitment of genuine mesenchymal cells from the peritumoral stroma. Cells of both the epithelial...... compartment and the stromal compartment express alpha smooth muscle actin (alpha-sm actin) as part of a myoepithelial or a myofibroblastic differentiation program, respectively. Moreover, because both epithelial- and mesenchymal-derived cells are nontumorigenic, other means of discrimination are warranted....... Here, we describe the contraction of hydrated collagen gels as a rapid functional assay for the distinction between epithelial- and mesenchymal-derived stromal-like cells irrespective of the status of alpha-sm actin expression. Three epithelial-derived cell lines and three genuine mesenchymal...

Biomimetic mineralization of recombinant collagen type I derived protein to obtain hybrid matrices for bone regeneration.

Science.gov (United States)

Ramírez-Rodríguez, Gloria Belén; Delgado-López, José Manuel; Iafisco, Michele; Montesi, Monica; Sandri, Monica; Sprio, Simone; Tampieri, Anna

2016-11-01

Understanding the mineralization mechanism of synthetic protein has recently aroused great interest especially in the development of advanced materials for bone regeneration. Herein, we propose the synthesis of composite materials through the mineralization of a recombinant collagen type I derived protein (RCP) enriched with RGD sequences in the presence of magnesium ions (Mg) to closer mimic bone composition. The role of both RCP and Mg ions in controlling the precipitation of the mineral phase is in depth evaluated. TEM and X-ray powder diffraction reveal the crystallization of nanocrystalline apatite (Ap) in all the evaluated conditions. However, Raman spectra point out also the precipitation of amorphous calcium phosphate (ACP). This amorphous phase is more evident when RCP and Mg are at work, indicating the synergistic role of both in stabilizing the amorphous precursor. In addition, hybrid matrices are prepared to tentatively address their effectiveness as scaffolds for bone tissue engineering. SEM and AFM imaging show an homogeneous mineral distribution on the RCP matrix mineralized in presence of Mg, which provides a surface roughness similar to that found in bone. Preliminary in vitro tests with pre-osteoblast cell line show good cell-material interaction on the matrices prepared in the presence of Mg. To the best of our knowledge this work represents the first attempt to mineralize recombinant collagen type I derived protein proving the simultaneous effect of the organic phase (RCP) and Mg on ACP stabilization. This study opens the possibility to engineer, through biomineralization process, advanced hybrid matrices for bone regeneration. Copyright © 2016 Elsevier Inc. All rights reserved.

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.

Novel N-substituted aminobenzamide scaffold derivatives targeting the dipeptidyl peptidase-IV enzyme

Directory of Open Access Journals (Sweden)

Al-Balas QA

2014-01-01

-nine novel compounds having an N-aminobenzamide scaffold were prepared, with full characterization. Ten of these compounds showed more in vitro activity against DPP-IV than the reference compounds, with the most active compounds scoring 38% activity at 100 µM concentration.Conclusion: The N-aminobenzamide scaffold was shown in this study to be a valid scaffold for inhibiting the DPP-IV enzyme. Continuing work could unravel more active compounds possessing the same scaffold.Keywords: diabetes mellitus, dipeptidyl peptidase-IV, aminobenzamide derivatives, hypoglycemic activity, CDOCKER software

Skeletal muscle collagen content in humans after high-force eccentric contractions

DEFF Research Database (Denmark)

Mackey, Abigail; Donnelly, Alan E; Turpeenniemi-Hujanen, Taina

2004-01-01

The purpose of this study was to investigate the effects of high-force eccentric muscle contractions on collagen remodeling and on circulating levels of matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMP) in humans. Nine volunteers [5 men and 4 women, mean age 23 (SD...... 4) yr] each performed a bout of 100 maximum voluntary eccentric contractions of the knee extensors. Muscle biopsies were taken before exercise and on days 4 and 22 afterward. Image analysis of stained tissue sections was used to quantify endomysial collagen staining intensity. Maximum voluntary...... contractile force declined by 39 +/- 23% (mean +/- SD) on day 2 postexercise and recovered thereafter. Serum creatine kinase activity peaked on day 4 postexercise (P Collagen type IV staining intensity increased significantly on day 22 postexercise to 126 +/- 29% (mean +/- SD) of preexercise values...

Natural Type II Collagen Hydrogel, Fibrin Sealant, and Adipose-Derived Stem Cells as a Promising Combination for Articular Cartilage Repair.

Science.gov (United States)

Lazarini, Mariana; Bordeaux-Rego, Pedro; Giardini-Rosa, Renata; Duarte, Adriana S S; Baratti, Mariana Ozello; Zorzi, Alessandro Rozim; de Miranda, João Batista; Lenz Cesar, Carlos; Luzo, Ângela; Olalla Saad, Sara Teresinha

2017-10-01

Objective Articular cartilage is an avascular tissue with limited ability of self-regeneration and the current clinical treatments have restricted capacity to restore damages induced by trauma or diseases. Therefore, new techniques are being tested for cartilage repair, using scaffolds and/or stem cells. Although type II collagen hydrogel, fibrin sealant, and adipose-derived stem cells (ASCs) represent suitable alternatives for cartilage formation, their combination has not yet been investigated in vivo for focal articular cartilage defects. We performed a simple experimental procedure using the combination of these 3 compounds on cartilage lesions of rabbit knees. Design The hydrogel was developed in house and was first tested in vitro for chondrogenic differentiation. Next, implants were performed in chondral defects with or without ASCs and the degree of regeneration was macroscopically and microscopically evaluated. Results Production of proteoglycans and the increased expression of collagen type II (COL2α1), aggrecan (ACAN), and sex-determining region Y-box 9 (SOX9) confirmed the chondrogenic character of ASCs in the hydrogel in vitro. Importantly, the addition of ASC induced a higher overall repair of the chondral lesions and a better cellular organization and collagen fiber alignment compared with the same treatment without ASCs. This regenerating tissue also presented the expression of cartilage glycosaminoglycan and type II collagen. Conclusions Our results indicate that the combination of the 3 compounds is effective for articular cartilage repair and may be of future clinical interest.

Including osteoprotegerin and collagen IV in a score-based blood test for liver fibrosis increases diagnostic accuracy.

Science.gov (United States)

Bosselut, Nelly; Taibi, Ludmia; Guéchot, Jérôme; Zarski, Jean-Pierre; Sturm, Nathalie; Gelineau, Marie-Christine; Poggi, Bernard; Thoret, Sophie; Lasnier, Elisabeth; Baudin, Bruno; Housset, Chantal; Vaubourdolle, Michel

2013-01-16

Noninvasive methods for liver fibrosis evaluation in chronic liver diseases have been recently developed, i.e. transient elastography (Fibroscan™) and blood tests (Fibrometer®, Fibrotest®, and Hepascore®). In this study, we aimed to design a new score in chronic hepatitis C (CHC) by selecting blood markers in a large panel and we compared its diagnostic performance with those of other noninvasive methods. Sixteen blood tests were performed in 306 untreated CHC patients included in a multicenter prospective study (ANRS HC EP 23 Fibrostar) using METAVIR histological fibrosis stage as reference. The new score was constructed by non linear regression using the most accurate biomarkers. Five markers (alpha-2-macroglobulin, apolipoprotein-A1, AST, collagen IV and osteoprotegerin) were included in the new function called Coopscore©. Using the Obuchowski Index, Coopscore© shows higher diagnostic performances than for Fibrometer®, Fibrotest®, Hepascore® and Fibroscan™ in CHC. Association between Fibroscan™ and Coopscore© might avoid 68% of liver biopsies for the diagnosis of significant fibrosis. Coopscore© provides higher accuracy than other noninvasive methods for the diagnosis of liver fibrosis in CHC. The association of Coopscore© with Fibroscan™ increases its predictive value. Copyright © 2012 Elsevier B.V. All rights reserved.

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.

Transient expression of collagen type II at epitheliomesenchymal interfaces during morphogenesis of the cartilaginous neurocranium.

Science.gov (United States)

Thorogood, P; Bee, J; von der Mark, K

1986-08-01

In the avian embryo a matrix-mediated tissue interaction between retinal pigmented epithelium and neural crest-derived periocular mesenchyme leads to the differentiation of (scleral) cartilage. The composition of the extracellular matrix at the interface between these two tissues has been examined immunohistochemically, both during and after the interaction has taken place. Of the matrix components studied (fibronectin, laminin, and collagen types I, II, IV, and V) only collagen type II displayed a dramatic change in distribution between the two stages. During the interaction, at stage 15, type II was present in the extracellular compartment basal to the epithelium. After completion of the interaction, collagen type II was no longer detectable at the interface even though it was readily detectable in the vitreous humor, cornea, and perinotochordal sheath, and subsequently will be expressed by the chondrogenic tissue itself as overt differentiation commences. These results suggest that collagen type II might be causally involved in this particular epitheliomesenchymal interaction. Examination of the spatial and temporal patterns of collagen type II expression elsewhere in the developing craniofacial complex revealed a hitherto unreported pattern of distribution. In addition to its predictable locations (i.e., cornea, vitreous, and perinotochordal sheath) it was found to be present at certain other sites, for example, at the basal surfaces of some neuroepithelia. These additional locations are all known to be sites of chondrogenesis-promoting tissue interactions which result in the formation of the elements of the cartilaginous neurocranium (e.g., otic vesicle). Furthermore this spatial distribution exhibits a changing temporal pattern in that it is detectable at the time that the interactions are known to be taking place, but subsequently is no longer detectable by the immunohistochemical means employed. This definable pattern of transient collagen type II

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.

Relationship between serum IV-C, β2-m levels and diabetic nephropathy

International Nuclear Information System (INIS)

Liu Lu; Zhang Mukun

2005-01-01

Objective: To investigate the relationship between the serum type IV collagen (IV-C), β 2 -micro globulin (β 2 -m) levels and diabetic nephropathy. Methods: Serum IV-C, β 2 -m levels were measured with RIA in 30 controls and 86 patients with type 2 diabetics mellitus (35 with diabetic nephropathy and 51 without nephropathy). Results: the serum levels of IV-C and β 2 -m in diabetic patients with nephropathy were significantly higher than those in controls (P 0.05). Conclusion: Serum IV-C and β 2 -m levels increased gradually as the diabetic nephropathy got more severe. They could be a sensitive marker for early diagnosis of development of diabetic nephropathy. (authors)

Functional Imaging of Proteolysis: Stromal and Inflammatory Cells Increase Tumor Proteolysis

Directory of Open Access Journals (Sweden)

Mansoureh Sameni

2003-07-01

Full Text Available The underlying basement membrane is degraded during progression of breast and colon carcinoma. Thus, we imaged degradation of a quenched fluorescent derivative of basement membrane type IV collagen (DQ-collagen IV by living human breast and colon tumor spheroids. Proteolysis of DQ-collagen IV by HCT 116 and HKh-2 human colon tumor spheroids was both intracellular and pericellular. In contrast, proteolysis of DQ-collagen IV by BT20 human breast tumor spheroids was pericellular. As stromal elements can contribute to proteolytic activities associated with tumors, we also examined degradation of DQ-collagen IV by human monocytes/macrophages and colon and breast fibroblasts. Fibroblasts themselves exhibited a modest amount of pericellular degradation. Degradation was increased 4–17-fold in cocultures of fibroblasts and tumor cells as compared to either cell type alone. Inhibitors of matrix metalloproteinases, plasmin, and the cysteine protease, cathepsin B, all reduced degradation in the cocultures. Monocytes did not degrade DQ-collagen IV; however, macrophages degraded DQ-collagen IV intracellularly. In coculture of tumor cells, fibroblasts, and macrophages, degradation of DQ-collagen IV was further increased. Imaging of living tumor and stromal cells has, thus, allowed us to establish that tumor proteolysis occurs pericellularly and intracellularly and that tumor, stromal, and inflammatory cells all contribute to degradative processes.

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

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

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.

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.

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.

Fibroblast Activation Protein (FAP) Accelerates Collagen Degradation and Clearance from Lungs in Mice

DEFF Research Database (Denmark)

Fan, Ming-Hui; Zhu, Qiang; Li, Hui-Hua

2016-01-01

, intratracheal bleomycin instillation and thoracic irradiation, we find increased mortality and increased lung fibrosis in FAP-deficient mice compared with wild-type mice. Lung extracellular matrix analysis reveals accumulation of intermediate-sized collagen fragments in FAP-deficient mouse lungs, consistent...... within vitrostudies showing that FAP mediates ordered proteolytic processing of matrix metalloproteinase (MMP)-derived collagen cleavage products. FAP-mediated collagen processing leads to increased collagen internalization without altering expression of the endocytic collagen receptor, Endo180....... Pharmacologic FAP inhibition decreases collagen internalization as expected. Conversely, restoration of FAP expression in the lungs of FAP-deficient mice decreases lung hydroxyproline content after intratracheal bleomycin to levels comparable with that of wild-type controls. Our findings indicate that FAP...

Lsa63, a newly identified surface protein of Leptospira interrogans binds laminin and collagen IV.

Science.gov (United States)

Vieira, Monica L; de Morais, Zenaide M; Gonçales, Amane P; Romero, Eliete C; Vasconcellos, Silvio A; Nascimento, Ana L T O

2010-01-01

Leptospira interrogans is the etiological agent of leptospirosis, a zoonotic disease that affects populations worldwide. We have identified in proteomic studies a protein that is encoded by the gene LIC10314 and expressed in virulent strain of L. interrogans serovar Pomona. This protein was predicted to be surface exposed by PSORT program and contains a p83/100 domain identified by BLAST analysis that is conserved in protein antigens of several strains of Borrelia and Treponema spp. The proteins containing this domain have been claimed antigen candidates for serodiagnosis of Lyme borreliosis. Thus, we have cloned the LIC10314 and expressed the protein in Escherichia coli BL21-SI strain by using the expression vector pAE. The recombinant protein tagged with N-terminal hexahistidine was purified by metal-charged chromatography and characterized by circular dichroism spectroscopy. This protein is conserved among several species of pathogenic Leptospira and absent in the saprophytic strain L. biflexa. We confirm by liquid-phase immunofluorescence assays with living organisms that this protein is most likely a new surface leptospiral protein. The ability of the protein to mediate attachment to ECM components was evaluated by binding assays. The leptospiral protein encoded by LIC10314, named Lsa63 (Leptospiral surface adhesin of 63kDa), binds strongly to laminin and collagen IV in a dose-dependent and saturable fashion. In addition, Lsa63 is probably expressed during infection since it was recognized by antibodies of serum samples of confirmed-leptospirosis patients in convalescent phase of the disease. Altogether, the data suggests that this novel identified surface protein may be involved in leptospiral pathogenesis. 2009 The British Infection Society. Published by Elsevier Ltd. All rights reserved.

Cyclophilin-B Modulates Collagen Cross-linking by Differentially Affecting Lysine Hydroxylation in the Helical and Telopeptidyl Domains of Tendon Type I Collagen.

Science.gov (United States)

Terajima, Masahiko; Taga, Yuki; Chen, Yulong; Cabral, Wayne A; Hou-Fu, Guo; Srisawasdi, Sirivimol; Nagasawa, Masako; Sumida, Noriko; Hattori, Shunji; Kurie, Jonathan M; Marini, Joan C; Yamauchi, Mitsuo

2016-04-29

Covalent intermolecular cross-linking provides collagen fibrils with stability. The cross-linking chemistry is tissue-specific and determined primarily by the state of lysine hydroxylation at specific sites. A recent study on cyclophilin B (CypB) null mice, a model of recessive osteogenesis imperfecta, demonstrated that lysine hydroxylation at the helical cross-linking site of bone type I collagen was diminished in these animals (Cabral, W. A., Perdivara, I., Weis, M., Terajima, M., Blissett, A. R., Chang, W., Perosky, J. E., Makareeva, E. N., Mertz, E. L., Leikin, S., Tomer, K. B., Kozloff, K. M., Eyre, D. R., Yamauchi, M., and Marini, J. C. (2014) PLoS Genet 10, e1004465). However, the extent of decrease appears to be tissue- and molecular site-specific, the mechanism of which is unknown. Here we report that although CypB deficiency resulted in lower lysine hydroxylation in the helical cross-linking sites, it was increased in the telopeptide cross-linking sites in tendon type I collagen. This resulted in a decrease in the lysine aldehyde-derived cross-links but generation of hydroxylysine aldehyde-derived cross-links. The latter were absent from the wild type and heterozygous mice. Glycosylation of hydroxylysine residues was moderately increased in the CypB null tendon. We found that CypB interacted with all lysyl hydroxylase isoforms (isoforms 1-3) and a putative lysyl hydroxylase-2 chaperone, 65-kDa FK506-binding protein. Tendon collagen in CypB null mice showed severe size and organizational abnormalities. The data indicate that CypB modulates collagen cross-linking by differentially affecting lysine hydroxylation in a site-specific manner, possibly via its interaction with lysyl hydroxylases and associated molecules. This study underscores the critical importance of collagen post-translational modifications in connective tissue formation. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Cyclophilin-B Modulates Collagen Cross-linking by Differentially Affecting Lysine Hydroxylation in the Helical and Telopeptidyl Domains of Tendon Type I Collagen*

Science.gov (United States)

Terajima, Masahiko; Taga, Yuki; Chen, Yulong; Cabral, Wayne A.; Hou-Fu, Guo; Srisawasdi, Sirivimol; Nagasawa, Masako; Sumida, Noriko; Hattori, Shunji; Kurie, Jonathan M.; Marini, Joan C.; Yamauchi, Mitsuo

2016-01-01

Covalent intermolecular cross-linking provides collagen fibrils with stability. The cross-linking chemistry is tissue-specific and determined primarily by the state of lysine hydroxylation at specific sites. A recent study on cyclophilin B (CypB) null mice, a model of recessive osteogenesis imperfecta, demonstrated that lysine hydroxylation at the helical cross-linking site of bone type I collagen was diminished in these animals (Cabral, W. A., Perdivara, I., Weis, M., Terajima, M., Blissett, A. R., Chang, W., Perosky, J. E., Makareeva, E. N., Mertz, E. L., Leikin, S., Tomer, K. B., Kozloff, K. M., Eyre, D. R., Yamauchi, M., and Marini, J. C. (2014) PLoS Genet. 10, e1004465). However, the extent of decrease appears to be tissue- and molecular site-specific, the mechanism of which is unknown. Here we report that although CypB deficiency resulted in lower lysine hydroxylation in the helical cross-linking sites, it was increased in the telopeptide cross-linking sites in tendon type I collagen. This resulted in a decrease in the lysine aldehyde-derived cross-links but generation of hydroxylysine aldehyde-derived cross-links. The latter were absent from the wild type and heterozygous mice. Glycosylation of hydroxylysine residues was moderately increased in the CypB null tendon. We found that CypB interacted with all lysyl hydroxylase isoforms (isoforms 1–3) and a putative lysyl hydroxylase-2 chaperone, 65-kDa FK506-binding protein. Tendon collagen in CypB null mice showed severe size and organizational abnormalities. The data indicate that CypB modulates collagen cross-linking by differentially affecting lysine hydroxylation in a site-specific manner, possibly via its interaction with lysyl hydroxylases and associated molecules. This study underscores the critical importance of collagen post-translational modifications in connective tissue formation. PMID:26934917

Development of Collagen/Demineralized Bone Powder Scaffolds and Periosteum-Derived Cells for Bone Tissue Engineering Application

Directory of Open Access Journals (Sweden)

Wilairat Leeanansaksiri

2013-01-01

Full Text Available The aim of this study was to investigate physical and biological properties of collagen (COL and demineralized bone powder (DBP scaffolds for bone tissue engineering. DBP was prepared and divided into three groups, based on various particle sizes: 75–125 µm, 125–250 µm, and 250–500 µm. DBP was homogeneously mixed with type I collagen and three-dimensional scaffolds were constructed, applying chemical crosslinking and lyophilization. Upon culture with human periosteum-derived cells (PD cells, osteogenic differentiation of PD cells was investigated using alkaline phosphatase (ALP activity and calcium assay kits. The physical properties of the COL/DBP scaffolds were obviously different from COL scaffolds, irrespective of the size of DBP. In addition, PD cells cultured with COL scaffolds showed significantly higher cell adhesion and proliferation than those with COL/DBP scaffolds. In contrast, COL/DBP scaffolds exhibited greater osteoinductive potential than COL scaffolds. The PD cells with COL/DBP scaffolds possessed higher ALP activity than those with COL scaffolds. PD cells cultured with COL/DBP scaffolds with 250–500 mm particle size yielded the maximum calcium deposition. In conclusion, PD cells cultured on the scaffolds could exhibit osteoinductive potential. The composite scaffold of COL/DBP with 250–500 mm particle size could be considered a potential bone tissue engineering implant.

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...

A comparative study of the properties and self-aggregation behavior of collagens from the scales and skin of grass carp (Ctenopharyngodon idella).

Science.gov (United States)

Liu, Yaowen; Ma, Donghui; Wang, Yihao; Qin, Wen

2018-01-01

Collagens were extracted from the scales and skin of Ctenopharyngodon idella (C. idella) as raw materials using an acid-enzyme hybrid method. The structural properties of the extracted collagens were compared using ultraviolet-visible spectrophotometry, Fourier transform infrared spectroscopy, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and differential scanning calorimetry. Additionally, the in vitro self-aggregation behaviors of the two types of collagens (fish skin- and scale-derived collagens) were compared using turbidimetric assays, aggregation assays, and scanning electron microscopy (SEM). The results showed that both types of extracted collagen were typical type I collagen with two α chains and intact triple-helical structures. The denaturation temperatures of the collagens from fish scales and skin were 34.99°C and 39.75°C, respectively. Both types of collagens were capable of self-aggregation in neutral salt solution at 30°C, with aggregation degrees of 28% and 27.33% for the scale and skin collagens, respectively. SEM analysis revealed that both types of collagens could self-aggregate into interwoven fibers, and the fish scale-derived collagen had a more pronounced reticular fiber structure with a striped periodic D-band pattern of collagen fibrils, whereas the collagen fibers from the self-aggregation of fish skin-derived collagen had a certain degree of disruption without any D-band pattern. Copyright © 2017 Elsevier B.V. All rights reserved.

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

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.

FTIR spectro-imaging of collagen scaffold formation during glioma tumor development.

Science.gov (United States)

Noreen, Razia; Chien, Chia-Chi; Chen, Hsiang-Hsin; Bobroff, Vladimir; Moenner, Michel; Javerzat, Sophie; Hwu, Yeukuang; Petibois, Cyril

2013-11-01

Evidence has recently emerged that solid and diffuse tumors produce a specific extracellular matrix (ECM) for division and diffusion, also developing a specific interface with microvasculature. This ECM is mainly composed of collagens and their scaffolding appears to drive tumor growth. Although collagens are not easily analyzable by UV-fluorescence means, FTIR imaging has appeared as a valuable tool to characterize collagen contents in tissues, specially the brain, where ECM is normally devoid of collagen proteins. Here, we used FTIR imaging to characterize collagen content changes in growing glioma tumors. We could determine that C6-derived solid tumors presented high content of triple helix after 8-11 days of growth (typical of collagen fibrils formation; 8/8 tumor samples; 91 % of total variance), and further turned to larger α-helix (days 12-15; 9/10 of tumors; 94 % of variance) and β-turns (day 18-21; 7/8 tumors; 97 % of variance) contents, which suggest the incorporation of non-fibrillar collagen types in ECM, a sign of more and more organized collagen scaffold along tumor progression. The growth of tumors was also associated to the level of collagen produced (P < 0.05). This study thus confirms that collagen scaffolding is a major event accompanying the angiogenic shift and faster tumor growth in solid glioma phenotypes.

Examining the Stability of "DSM-IV" and Empirically Derived Eating Disorder Classification: Implications for "DSM-5"

Science.gov (United States)

Peterson, Carol B.; Crow, Scott J.; Swanson, Sonja A.; Crosby, Ross D.; Wonderlich, Stephen A.; Mitchell, James E.; Agras, W. Stewart; Halmi, Katherine A.

2011-01-01

Objective: The purpose of this investigation was to derive an empirical classification of eating disorder symptoms in a heterogeneous eating disorder sample using latent class analysis (LCA) and to examine the longitudinal stability of these latent classes (LCs) and the stability of DSM-IV eating disorder (ED) diagnoses. Method: A total of 429…

Time domain diffuse optical spectroscopy: In vivo quantification of collagen in breast tissue

Science.gov (United States)

Taroni, Paola; Pifferi, Antonio; Quarto, Giovanna; Farina, Andrea; Ieva, Francesca; Paganoni, Anna Maria; Abbate, Francesca; Cassano, Enrico; Cubeddu, Rinaldo

2015-05-01

Time-resolved diffuse optical spectroscopy provides non-invasively the optical characterization of highly diffusive media, such as biological tissues. Light pulses are injected into the tissue and the effects of light propagation on re-emitted pulses are interpreted with the diffusion theory to assess simultaneously tissue absorption and reduced scattering coefficients. Performing spectral measurements, information on tissue composition and structure is derived applying the Beer law to the measured absorption and an empiric approximation to Mie theory to the reduced scattering. The absorption properties of collagen powder were preliminarily measured in the range of 600-1100 nm using a laboratory set-up for broadband time-resolved diffuse optical spectroscopy. Optical projection images were subsequently acquired in compressed breast geometry on 218 subjects, either healthy or bearing breast lesions, using a portable instrument for optical mammography that operates at 7 wavelengths selected in the range 635-1060 nm. For all subjects, tissue composition was estimated in terms of oxy- and deoxy-hemoglobin, water, lipids, and collagen. Information on tissue microscopic structure was also derived. Good correlation was obtained between mammographic breast density (a strong risk factor for breast cancer) and an optical index based on collagen content and scattering power (that accounts mostly for tissue collagen). Logistic regression applied to all optically derived parameters showed that subjects at high risk for developing breast cancer for their high breast density can effectively be identified based on collagen content and scattering parameters. Tissue composition assessed in breast lesions with a perturbative approach indicated that collagen and hemoglobin content are significantly higher in malignant lesions than in benign ones.

Normal Collagen and Bone Production by Gene-targeted Human Osteogenesis Imperfecta iPSCs

Science.gov (United States)

Deyle, David R; Khan, Iram F; Ren, Gaoying; Wang, Pei-Rong; Kho, Jordan; Schwarze, Ulrike; Russell, David W

2012-01-01

Osteogenesis imperfecta (OI) is caused by dominant mutations in the type I collagen genes. In principle, the skeletal abnormalities of OI could be treated by transplantation of patient-specific, bone-forming cells that no longer express the mutant gene. Here, we develop this approach by isolating mesenchymal cells from OI patients, inactivating their mutant collagen genes by adeno-associated virus (AAV)-mediated gene targeting, and deriving induced pluripotent stem cells (iPSCs) that were expanded and differentiated into mesenchymal stem cells (iMSCs). Gene-targeted iMSCs produced normal collagen and formed bone in vivo, but were less senescent and proliferated more than bone-derived MSCs. To generate iPSCs that would be more appropriate for clinical use, the reprogramming and selectable marker transgenes were removed by Cre recombinase. These results demonstrate that the combination of gene targeting and iPSC derivation can be used to produce potentially therapeutic cells from patients with genetic disease. PMID:22031238

Chondrogenic differentiation of mesenchymal stem cells in a leakproof collagen sponge

International Nuclear Information System (INIS)

Chen Guoping; Akahane, Daisuke; Kawazoe, Naoki; Yamamoto, Katsuyuki; Tateishi, Tetsuya

2008-01-01

A three-dimensional culture of mesenchymal stem cells (MSCs) in a porous scaffold has been developed as a promising strategy for cartilage tissue engineering. The chondrogenic differentiation of MSCs derived from human bone marrow was studied by culturing the cells in a novel scaffold constructed of leakproof collagen sponge. All the surfaces of the collagen sponge except the top were wrapped with a membrane that has pores smaller than the cells to protect against cell leakage during cell seeding. The cells adhered to the collagen, distributed evenly, and proliferated to fill the spaces in the sponge. Cell seeding efficiency was greater than 95%. The MSCs cultured in the collagen sponge in the presence of TGF-β3 and BMP6 expressed a high level of genes encoding type II and type X collagen, sox9, and aggrecan. Histological examination by HE staining indicated that the differentiated cells showed a round morphology. The extracellular matrices were positively stained by safranin O and toluidine blue. Immunostaining with anti-type II collagen and anti-cartilage proteoglycan showed that type II collagen and cartilage proteoglycan were detected around the cells. These results suggest the chondrogenic differentiation of MSCs when cultured in the collagen sponge in the presence of TGF-β3 and BMP6

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.

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.

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

Toward single cell traction microscopy within 3D collagen matrices

Energy Technology Data Exchange (ETDEWEB)

Hall, Matthew S. [Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853 (United States); Long, Rong [Department of Mechanical Engineering, University of Alberta, Edmonton, AB, Canada T6G 2G8 (Canada); Feng, Xinzeng [Department of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853 (United States); Huang, YuLing [Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853 (United States); Hui, Chung-Yuen [Department of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853 (United States); Wu, Mingming, E-mail: mw272@cornell.edu [Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853 (United States)

2013-10-01

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.

Role of collagens and perlecan in microvascular stability: exploring the mechanism of capillary vessel damage by snake venom metalloproteinases.

Directory of Open Access Journals (Sweden)

Teresa Escalante

Full Text Available Hemorrhage is a clinically important manifestation of viperid snakebite envenomings, and is induced by snake venom metalloproteinases (SVMPs. Hemorrhagic and non-hemorrhagic SVMPs hydrolyze some basement membrane (BM and associated extracellular matrix (ECM proteins. Nevertheless, only hemorrhagic SVMPs are able to disrupt microvessels; the mechanisms behind this functional difference remain largely unknown. We compared the proteolytic activity of the hemorrhagic P-I SVMP BaP1, from the venom of Bothrops asper, and the non-hemorrhagic P-I SVMP leucurolysin-a (leuc-a, from the venom of Bothrops leucurus, on several substrates in vitro and in vivo, focusing on BM proteins. When incubated with Matrigel, a soluble extract of BM, both enzymes hydrolyzed laminin, nidogen and perlecan, albeit BaP1 did it at a faster rate. Type IV collagen was readily digested by BaP1 while leuc-a only induced a slight hydrolysis. Degradation of BM proteins in vivo was studied in mouse gastrocnemius muscle. Western blot analysis of muscle tissue homogenates showed a similar degradation of laminin chains by both enzymes, whereas nidogen was cleaved to a higher extent by BaP1, and perlecan and type IV collagen were readily digested by BaP1 but not by leuc-a. Immunohistochemistry of muscle tissue samples showed a decrease in the immunostaining of type IV collagen after injection of BaP1, but not by leuc-a. Proteomic analysis by LC/MS/MS of exudates collected from injected muscle revealed higher amounts of perlecan, and types VI and XV collagens, in exudates from BaP1-injected tissue. The differences in the hemorrhagic activity of these SVMPs could be explained by their variable ability to degrade key BM and associated ECM substrates in vivo, particularly perlecan and several non-fibrillar collagens, which play a mechanical stabilizing role in microvessel structure. These results underscore the key role played by these ECM components in the mechanical stability of

Skin Antiageing and Systemic Redox Effects of Supplementation with Marine Collagen Peptides and Plant-Derived Antioxidants: A Single-Blind Case-Control Clinical Study

Directory of Open Access Journals (Sweden)

Chiara De Luca

2016-01-01

Full Text Available Recently, development and research of nutraceuticals based on marine collagen peptides (MCPs have been growing due to their high homology with human collagens, safety, bioavailability through gut, and numerous bioactivities. The major concern regarding safety of MCPs intake relates to increased risk of oxidative stress connected with collagen synthesis (likewise in fibrosis and to ROS production by MCPs-stimulated phagocytes. In this clinical-laboratory study, fish skin MCPs combined with plant-derived skin-targeting antioxidants (AO (coenzyme Q10 + grape-skin extract + luteolin + selenium were administered to volunteers (n=41. Skin properties (moisture, elasticity, sebum production, and biological age and ultrasonic markers (epidermal/dermal thickness and acoustic density were measured thrice (2 months before treatment and before and after cessation of 2-month oral intake. The supplementation remarkably improved skin elasticity, sebum production, and dermal ultrasonic markers. Metabolic data showed significant increase of plasma hydroxyproline and ATP storage in erythrocytes. Redox parameters, GSH/coenzyme Q10 content, and GPx/GST activities were unchanged, while NO and MDA were moderately increased within, however, normal range of values. Conclusions. A combination of MCPs with skin-targeting AOs could be effective and safe supplement to improve skin properties without risk of oxidative damage.

Skin Antiageing and Systemic Redox Effects of Supplementation with Marine Collagen Peptides and Plant-Derived Antioxidants: A Single-Blind Case-Control Clinical Study

Science.gov (United States)

De Luca, Chiara; Mikhal'chik, Elena V.; Suprun, Maxim V.; Papacharalambous, Michael; Truhanov, Arseniy I.; Korkina, Liudmila G.

2016-01-01

Recently, development and research of nutraceuticals based on marine collagen peptides (MCPs) have been growing due to their high homology with human collagens, safety, bioavailability through gut, and numerous bioactivities. The major concern regarding safety of MCPs intake relates to increased risk of oxidative stress connected with collagen synthesis (likewise in fibrosis) and to ROS production by MCPs-stimulated phagocytes. In this clinical-laboratory study, fish skin MCPs combined with plant-derived skin-targeting antioxidants (AO) (coenzyme Q10 + grape-skin extract + luteolin + selenium) were administered to volunteers (n = 41). Skin properties (moisture, elasticity, sebum production, and biological age) and ultrasonic markers (epidermal/dermal thickness and acoustic density) were measured thrice (2 months before treatment and before and after cessation of 2-month oral intake). The supplementation remarkably improved skin elasticity, sebum production, and dermal ultrasonic markers. Metabolic data showed significant increase of plasma hydroxyproline and ATP storage in erythrocytes. Redox parameters, GSH/coenzyme Q10 content, and GPx/GST activities were unchanged, while NO and MDA were moderately increased within, however, normal range of values. Conclusions. A combination of MCPs with skin-targeting AOs could be effective and safe supplement to improve skin properties without risk of oxidative damage. PMID:26904164

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.

Dynamic interplay between the collagen scaffold and tumor evolution

DEFF Research Database (Denmark)

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

2010-01-01

The extracellular matrix (ECM) is a key regulator of cell and tissue function. Traditionally, the ECM has been thought of primarily as a physical scaffold that binds cells and tissues together. However, the ECM also elicits biochemical and biophysical signaling. Controlled proteolysis...... 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...

Biosorption of thorium(IV) from aqueous solution by living biomass of marine-derived fungus Fusarium sp. ZZF51

International Nuclear Information System (INIS)

Yang, S.K.; Tan, N.; Wu, W.L.; Hou, X.J.; Xiang, K.X.; Lin, Y.C.

2015-01-01

The biosportion of Th(IV) by the marine-derived Fungus Fusarium sp. ZZF51 was study. The Biosorption was found to be at a maximum (79.24 %), in a solution containing 50 mg Th/L, at pH 5.0, with 0.28 g dry biomass. The Temkin isotherm model and pseudo-second-order kinetic model was found to fit the data very well over the entire range of concentrations. The FTIR analysis reveals that the carboxyl, amino and hydroxyl groups on the cell wall of Fusarium sp. ZZF51 play an important role in Th(IV) biosorption process. (author)

Prominent Vascularization Capacity of Mesenchymal Stem Cells in Collagen-Gold Nanocomposites.

Science.gov (United States)

Hsieh, Shu-Chen; Chen, Hui-Jye; Hsu, Shan-Hui; Yang, Yi-Chin; Tang, Cheng-Ming; Chu, Mei-Yun; Lin, Pei-Ying; Fu, Ru-Huei; Kung, Mei-Lang; Chen, Yun-Wen; Yeh, Bi-Wen; Hung, Huey-Shan

2016-10-26

The ideal characteristics of surface modification on the vascular graft for clinical application would be with excellent hemocompatibility, endothelialization capacity, and antirestenosis ability. Here, Fourier transform infrared spectroscopy (FTIR), surface enhanced Raman spectroscopy (SERS), atomic force microscopy (AFM), contact angle (θ) measurement, and thermogravimetric analysis (TGA) were used to evaluate the chemical and mechanical properties of collagen-gold nanocomposites (collagen+Au) with 17.4, 43.5, and 174 ppm of Au and suggested that the collagen+Au with 43.5 ppm of Au had better biomechanical properties and thermal stability than pure collagen. Besides, stromal-derived factor-1α (SDF-1α) at 50 ng/mL promoted the migration of mesenchymal stem cells (MSCs) on collagen+Au material through the α5β3 integrin/endothelial oxide synthase (eNOS)/metalloproteinase (MMP) signaling pathway which can be abolished by the knockdown of vascular endothelial growth factor (VEGF). The potentiality of collagen+Au with MSCs for vascular regeneration was evaluated by our in vivo rat model system. Artery tissues isolated from an implanted collagen+Au-coated catheter with MSCs expressed substantial CD-31 and α-SMA, displayed higher antifibrotic ability, antithrombotic activity, as well as anti-inflammatory response than all other materials. Our results indicated that the implantation of collagen+Au-coated catheters with MSCs could be a promising strategy for vascular regeneration.

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 ...

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.

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...

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...

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.

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...

Fabrication of human hair keratin/jellyfish collagen/eggshell-derived hydroxyapatite osteoinductive biocomposite scaffolds for bone tissue engineering: From waste to regenerative medicine products.

Science.gov (United States)

Arslan, Yavuz Emre; Sezgin Arslan, Tugba; Derkus, Burak; Emregul, Emel; Emregul, Kaan C

2017-06-01

In the present study, we aimed at fabricating an osteoinductive biocomposite scaffold using keratin obtained from human hair, jellyfish collagen and eggshell-derived nano-sized spherical hydroxyapatite (nHA) for bone tissue engineering applications. Keratin, collagen and nHA were characterized with the modified Lowry method, free-sulfhydryl groups and hydroxyproline content analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR) and thermal gravimetric analysis (TGA) which confirmed the success of the extraction and/or isolation processes. Human adipose mesenchymal stem cells (hAMSCs) were isolated and the cell surface markers were characterized via flow cytometry analysis in addition to multilineage differentiation capacity. The undifferentiated hAMSCs were highly positive for CD29, CD44, CD73, CD90 and CD105, but were not seen to express hematopoietic cell surface markers such as CD14, CD34 and CD45. The cells were successfully directed towards osteogenic, chondrogenic and adipogenic lineages in vitro. The microarchitecture of the scaffolds and cell attachment were evaluated using scanning electron microscopy (SEM). The cell viability on the scaffolds was assessed by the MTT assay which revealed no evidence of cytotoxicity. The osteogenic differentiation of hAMSCs on the scaffolds was determined histologically using alizarin red S, osteopontin and osteonectin stainings. Early osteogenic differentiation markers of hAMSCs were significantly expressed on the collagen-keratin-nHA scaffolds. In conclusion, it is believed that collagen-keratin-nHA osteoinductive biocomposite scaffolds have the potential of being used in bone tissue engineering. Copyright © 2017 Elsevier B.V. All rights reserved.

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.

In vivo topical application of acetyl aspartic acid increases fibrillin-1 and collagen IV deposition leading to a significant improvement of skin firmness.

Science.gov (United States)

Gillbro, J M; Merinville, E; Cattley, K; Al-Bader, T; Hagforsen, E; Nilsson, M; Mavon, A

2015-10-01

Acetyl aspartic acid (A-A-A) was discovered through gene array analysis with corresponding Cmap analysis. We found that A-A-A increased keratinocyte regeneration, inhibited dermal matrix metalloprotease (MMP) expression and relieved fibroblast stiffness through reduction of the fibroblast stiffness marker F-actin. Dermal absorption studies showed successful delivery to both the epidermal and dermal regions, and in-use trial demonstrated that 1% A-A-A was well tolerated. In this study, the aim was to investigate whether A-A-A could stimulate the synthesis of extracellular matrix supporting proteins in vivo and thereby improving the viscoelastic properties of human skin by conducting a dual histological and biophysical clinical study. Two separate double-blind vehicle-controlled in vivo studies were conducted using a 1% A-A-A containing oil-in-water (o/w) emulsion. In the histological study, 16 female volunteers (>55 years of age) exhibiting photodamaged skin on their forearm were included, investigating the effect of a 12-day treatment of A-A-A on collagen IV (COLIV) and fibrillin-1. In a subsequent pilot study, 0.1% retinol was used for comparison to A-A-A (1%). The biomechanical properties of the skin were assessed in a panel of 16 women (>45 years of age) using the standard Cutometer MPA580 after topical application of the test products for 28 days. The use of multiple suction enabled the assessment of F4, an area parameter specifically representing skin firmness. Twelve-day topical application of 1% A-A-A significantly increased COLIV and fibrillin with 13% and 6%, respectively, compared to vehicle. 1% A-A-A and 0.1% retinol were found to significantly reduce F4 after 28 days of treatment by 15.8% and 14.7%, respectively, in the pilot Cutometer study. No significant difference was found between retinol and A-A-A. However, only A-A-A exhibited a significant effect vs. vehicle on skin firmness which indicated the incremental benefit of A-A-A as a skin

Novel COL4A1 mutations associated with HANAC syndrome: a role for the triple helical CB3[IV] domain.

Science.gov (United States)

Plaisier, Emmanuelle; Chen, Zhiyong; Gekeler, Florian; Benhassine, Safa; Dahan, Karine; Marro, Béatrice; Alamowitch, Sonia; Paques, Michel; Ronco, Pierre

2010-10-01

The COL4A1 gene encodes the α1-chain of type IV collagen, which is ubiquitously expressed in basement membranes. Mutations in COL4A1 have been reported in autosomal-dominant porencephaly and in patients with symptomatic small vessel brain disease, inconstantly associated with eye defects. We have previously reported three COL4A1 mutations associated with a systemic phenotype that we called HANAC (Hereditary Angiopathy, Nephropathy, Aneurysms, and Cramps). We carried out a clinical and genetic study of three families presenting with characteristic features of HANAC syndrome. Common systemic signs included arterial retinal tortuosity and muscle cramps, with a variable combination of small vessel brain disease, Raynaud phenomena, and kidney defects. Three novel COL4A1 missense substitutions are described, which affect highly conserved glycine residues within the collagenous domain of the protein. All six known mutations associated with the HANAC phenotype are localized within the CB3[IV] fragment of COL4A1, which encompasses major integrin-binding sites. Our results confirm that HANAC syndrome is a distinct clinical entity within the COL4A1-related disorders, which is characterized by systemic involvement and usually asymptomatic brain disease. The restricted distribution of COL4A1 mutations within the CB3[IV] region is a characteristic of the reports of patients with HANAC, which suggests that abnormal cell-type IV collagen interactions may underlie the systemic defects observed in this syndrome. Copyright © 2010 Wiley-Liss, Inc.

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.

Clinical evaluation of the Serum CrossLaps One Step ELISA, a new assay measuring the serum concentration of bone-derived degradation products of type I collagen C-telopeptides

DEFF Research Database (Denmark)

Christgau, S; Rosenquist, C; Alexandersen, P

1998-01-01

The Serum CrossLaps One Step ELISA is a sandwich assay using two monoclonal antibodies specific for a beta-aspartate form of the epitope EKAHDGGR derived from the carboxy-terminal telopeptide region of type I collagen alpha1-chain. Our objective was to assess the clinical value of the Serum Cross...

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.

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 ...

The triple helix of collagens - an ancient protein structure that enabled animal multicellularity and tissue evolution.

Science.gov (United States)

Fidler, Aaron L; Boudko, Sergei P; Rokas, Antonis; Hudson, Billy G

2018-04-09

The cellular microenvironment, characterized by an extracellular matrix (ECM), played an essential role in the transition from unicellularity to multicellularity in animals (metazoans), and in the subsequent evolution of diverse animal tissues and organs. A major ECM component are members of the collagen superfamily -comprising 28 types in vertebrates - that exist in diverse supramolecular assemblies ranging from networks to fibrils. Each assembly is characterized by a hallmark feature, a protein structure called a triple helix. A current gap in knowledge is understanding the mechanisms of how the triple helix encodes and utilizes information in building scaffolds on the outside of cells. Type IV collagen, recently revealed as the evolutionarily most ancient member of the collagen superfamily, serves as an archetype for a fresh view of fundamental structural features of a triple helix that underlie the diversity of biological activities of collagens. In this Opinion, we argue that the triple helix is a protein structure of fundamental importance in building the extracellular matrix, which enabled animal multicellularity and tissue evolution. © 2018. Published by The Company of Biologists Ltd.

Bone Collagen: New Clues to its Mineralization Mechanism From Recessive Osteogenesis Imperfecta

Science.gov (United States)

Eyre, David R.; Ann Weis, Mary

2013-01-01

Until 2006 the only mutations known to cause osteogenesis imperfecta (OI) were in the two genes coding for type I collagen chains. These dominant mutations affecting the expression or primary sequence of collagen α1(I) and α2(I) chains account for over 90% of OI cases. Since then a growing list of mutant genes causing the 5–10% of recessive cases has rapidly emerged. They include CRTAP, LEPRE1 and PPIB, which encode three proteins forming the prolyl 3-hydroxylase complex; PLOD2 and FKBP10, which encode respectively lysyl hydroxylase 2 and a foldase required for its activity in forming mature cross-links in bone collagen; SERPIN H1, which encodes the collagen chaperone HSP47; SERPIN F1, which encodes pigment epithelium-derived factor required for osteoid mineralization; and BMP1, which encodes the type I procollagen C-propeptidase. All cause fragile bone in infancy, which can include over-mineralization or under-mineralization defects as well as abnormal collagen post-translational modifications. Consistently both dominant and recessive variants lead to abnormal cross-linking chemistry in bone collagen. These recent discoveries strengthen the potential for a common pathogenic mechanism of misassembled collagen fibrils. Of the new genes identified, eight encode proteins required for collagen post-translational modification, chaperoning of newly synthesized collagen chains into native molecules or transport through the endoplasmic reticulum and Golgi for polymerization, cross-linking and mineralization. In reviewing these findings, we conclude that a common theme is emerging in the pathogenesis of brittle bone disease of mishandled collagen assembly with important insights on post-translational features of bone collagen that have evolved to optimize it as a biomineral template. PMID:23508630

X-linked Alport syndrome associated with a synonymous p.Gly292Gly mutation alters the splicing donor site of the type IV collagen alpha chain 5 gene.

Science.gov (United States)

Fu, Xue Jun; Nozu, Kandai; Eguchi, Aya; Nozu, Yoshimi; Morisada, Naoya; Shono, Akemi; Taniguchi-Ikeda, Mariko; Shima, Yuko; Nakanishi, Koichi; Vorechovsky, Igor; Iijima, Kazumoto

2016-10-01

X-linked Alport syndrome (XLAS) is a progressive hereditary nephropathy caused by mutations in the type IV collagen alpha chain 5 gene (COL4A5). Although many COL4A5 mutations have previously been identified, pathogenic synonymous mutations have not yet been described. A family with XLAS underwent mutational analyses of COL4A5 by PCR and direct sequencing, as well as transcript analysis of potential splice site mutations. In silico analysis was also conducted to predict the disruption of splicing factor binding sites. Immunohistochemistry (IHC) of kidney biopsies was used to detect α2 and α5 chain expression. We identified a hemizygous point mutation, c.876A>T, in exon 15 of COL4A5 in the proband and his brother, which is predicted to result in a synonymous amino acid change, p.(Gly292Gly). Transcript analysis showed that this mutation potentially altered splicing because it disrupted the splicing factor binding site. The kidney biopsy of the proband showed lamellation of the glomerular basement membrane (GBM), while IHC revealed negative α5(IV) staining in the GBM and Bowman's capsule, which is typical of XLAS. This is the first report of a synonymous COL4A5 substitution being responsible for XLAS. Our findings suggest that transcript analysis should be conducted for the future correct assessment of silent mutations.

The Effect of Soy Isoflavone on the Proliferation and Differentiation of Adipose-Derived Mesenchymal Stem Cells into Chondrocytes and Expression of Collagen II and Aggrecan Genes

Directory of Open Access Journals (Sweden)

Fatemeh Bamdadpasand Shekarsarayi

2017-03-01

Full Text Available Background and Objectives: Due to the lack of blood vessels in cartilage tissue, its damage is not repairable. This study was conducted to investigate the effect of soy isoflavone on proliferation and differentiation of adipose-derived mesenchymal stem cells into chondrocytes and expression of collagen II and aggrecan genes. Methods: In this experimental study, human subcutaneous fat was obtained during liposuction and incubated with collagenase enzyme (type 1 for the breakdown of collagen, and collagenase was deactivated by DMEM medium, and was cultured in the cell sediment after centrifugation, the cells were isolated after the third passage, were placed in chondrogenic medium for differentiate into the cartilage, and were divided into three groups, including control, treatment with TGF-β1, and treatment with soy isoflavones tablets. The tablets were dissolved in distilled water, sterilized by passing through a 0.2 um filter and were added to the culture medium. After 48 hours, cell viability was determined by MTT assay, and after 14 days, collagen II and aggrecan gene expressions were assessed by real-time PCR technique. Data were statistically analyzed by one-way ANOVA and Tukey's post-hoc test using SPSS 20 and p<0.05. Results: The results of MTT assay showed a significant increase in viability in the TGF-β1 group compared to the control and soy isoflavone groups (p<0.05. The RT-PCR indicated a significant increase in the expression of collagen II and aggrecan genes in isoflavones and TGF-β1 groups compared to the control group, and also, the mean CT associated with collagen II gene had a significant increase in isoflavone and TGF-β1groups compared to the control group (p<0.05. Conclusion: Soy in culture medium increases the expression of collagen II and aggrecan genes and cell proliferation, but this increase is not high compared to the TGF-β1 group.

Collagen-derived dipeptide prolyl-hydroxyproline promotes differentiation of MC3T3-E1 osteoblastic cells

International Nuclear Information System (INIS)

Kimira, Yoshifumi; Ogura, Kana; Taniuchi, Yuri; Kataoka, Aya; Inoue, Naoki; Sugihara, Fumihito; Nakatani, Sachie; Shimizu, Jun; Wada, Masahiro; Mano, Hiroshi

2014-01-01

Highlights: • Pro-Hyp did not affect MC3T3-E1 cell proliferation and matrix mineralization. • Pro-Hyp significantly increased alkaline phosphatase activity. • Pro-Hyp significantly upregulated gene expression of Runx2, Osterix, and Col1α1. - Abstract: Prolyl-hydroxyproline (Pro-Hyp) is one of the major constituents of collagen-derived dipeptides. The objective of this study was to investigate the effects of Pro-Hyp on the proliferation and differentiation of MC3T3-E1 osteoblastic cells. Addition of Pro-Hyp did not affect MC3T3-E1 cell proliferation and matrix mineralization but alkaline phosphatase activity was significantly increased. Furthermore, cells treated with Pro-Hyp significantly upregulated gene expression of Runx2, Osterix, and Col1α1. These results indicate that Pro-Hyp promotes osteoblast differentiation. This study demonstrates for the first time that Pro-Hyp has a positive effect on osteoblast differentiation with upregulation of Runx2, Osterix, and Collα1 gene expression

Nitroxides are more efficient inhibitors of oxidative damage to calf skin collagen than antioxidant vitamins.

Science.gov (United States)

Venditti, Elisabetta; Scirè, Andrea; Tanfani, Fabio; Greci, Lucedio; Damiani, Elisabetta

2008-01-01

Reactive oxygen species generated upon UV-A exposure appear to play a major role in dermal connective tissue transformations including degradation of skin collagen. Here we investigate on oxidative damage to collagen achieved by exposure to (i) UV-A irradiation and to (ii) AAPH-derived radicals and on its possible prevention using synthetic and natural antioxidants. Oxidative damage was identified through SDS-PAGE, circular dichroism spectroscopy and quantification of protein carbonyl residues. Collagen (2 mg/ml) exposed to UV-A and to AAPH-derived radicals was degraded in a time- and dose-dependent manner. Upon UV-A exposure, maximum damage was observable at 730 kJ/m2 UV-A, found to be equivalent to roughly 2 h of sunshine, while exposure to 5 mM AAPH for 2 h at 50 degrees C lead to maximum collagen degradation. In both cases, dose-dependent protection was achieved by incubation with muM concentrations of nitroxide radicals, where the extent of protection was shown to be dictated by their structural differences whereas the vitamins E and C proved less efficient inhibitors of collagen damage. These results suggest that nitroxide radicals may be able to prevent oxidative injury to dermal tissues in vivo alternatively to commonly used natural antioxidants.

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

Glycosylation of type II collagen is of major importance for T cell tolerance and pathology in collagen-induced arthritis

DEFF Research Database (Denmark)

Bäcklund, Johan; Treschow, Alexandra; Bockermann, Robert

2002-01-01

Type II collagen (CII) is a candidate cartilage-specific autoantigen, which can become post-translationally modified by hydroxylation and glycosylation. T cell recognition of CII is essential for the development of murine collagen-induced arthritis (CIA) and also occurs in rheumatoid arthritis (RA......). The common denominator of murine CIA and human RA is the presentation of an immunodominant CII-derived glycosylated peptide on murine Aq and human DR4 molecules, respectively. To investigate the importance of T cell recognition of glycosylated CII in CIA development after immunization with heterologous CII......, we treated neonatal mice with different heterologous CII-peptides (non-modified, hydroxylated and galactosylated). Treatment with the galactosylated peptide (galactose at position 264) was superior in protecting mice from CIA. Protection was accompanied by a reduced antibody response to CII...

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

Use of collagen hydrolysate as a complex nitrogen source for the synthesis of penicillin by Penicillium chrysogenum.

Science.gov (United States)

Leonhartsberger, S; Lafferty, R M; Korneti, L

1993-09-01

Optimal conditions for both biomass formation and penicillin synthesis by a strain of Penicillium chrysogenum were determined when using a collagen-derived nitrogen source. Preliminary investigations were carried out in shaken flask cultures employing a planned experimental program termed the Graeco-Latin square technique (Auden et al., 1967). It was initially determined that up to 30% of a conventional complex nitrogen source such as cottonseed meal could be replaced by the collagen-derived nitrogen source without decreasing the productivity with respect to the penicillin yield. In the pilot scale experiments using a 30 l stirred tank type of bioreactor, higher penicillin yields were obtained when 70% of the conventional complex nitrogen source in the form of cottonseed meal was replaced by the collagen hydrolysate. Furthermore, the maximum rate of penicillin synthesis continued for over a longer period when using collagen hydrolysate as a complex nitrogen source. Penicillin synthesis rates were determined using a linear regression.

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.

[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.

Effects of immobilization and whole-body vibration on rat serum Type I collagen turnover.

Science.gov (United States)

Dönmez, Gürhan; Doral, Mahmut Nedim; Suljevic, Şenay; Sargon, Mustafa Fevzi; Bilgili, Hasan; Demirel, Haydar Ali

2016-08-01

The aim of this study was to investigate the effects of short-term, high-magnitude whole-body vibration (WBV) on serum type I collagen turnover in immobilized rats. Thirty Wistar albino rats were randomly divided into the following 5 groups: immobilization (IS), immobilization + remobilization (IR), immobilization + WBV (IV), control (C), and WBV control (CV). Immobilization was achieved by casting from the crista iliaca anterior superior to the lower part of the foot for 2 weeks. The applied WBV protocol involved a frequency of 45 Hz and amplitude of 3 mm for 7 days starting a day after the end of the immobilization period. Serum type I collagen turnover markers were measured by using ELISA kits. Serum NH2-terminal propeptide of type I collagen (PINP) levels were significantly lower in the immobilization groups (p immobilization groups. Similarly, serum COOH-terminal telopeptide of type I collagen (CTX) levels were higher in the WBV controls than their own controls (p Immobilization led to deterioration of tendon tissue, as observed by histopathological analysis with a transmission electron microscope. Although 1 week of WBV had a positive effect on type I collagen turnover in controls, it is not an efficient method for repairing tissue damage in the early stage following immobilization. Copyright © 2016 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

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.

The roles of TGF-beta1 gene transfer on collagen formation during Achilles tendon healing.

Science.gov (United States)

Hou, Yu; Mao, ZeBing; Wei, XueLei; Lin, Lin; Chen, LianXu; Wang, HaiJun; Fu, Xin; Zhang, JiYing; Yu, ChangLong

2009-05-29

Collagen content and cross-linking are believed to be major determinants of tendon structural integrity and function. The current study aimed to investigate the effects of transforming growth factor (TGF)-beta1 on the collagen content and cross-linking of Achilles tendons, and on the histological and biomechanical changes occurring during Achilles tendon healing in rabbits. Bone marrow-derived mesenchymal stem cells (BMSCs) transfected with the TGF-beta1 gene were surgically implanted into experimentally injured Achilles tendons. Collagen proteins were identified by immunohistochemical staining and fiber bundle accumulation was revealed by Sirius red staining. Achilles tendons treated with TGF-beta1-transfected BMSCs showed higher concentrations of collagen I protein, more rapid matrix remodeling, and larger fiber bundles. Thus TGF-beta1 can promote mechanical strength in healing Achilles tendons by regulating collagen synthesis, cross-link formation, and matrix remodeling.

Coordination and solvent extraction behaviour of oxozirconium(IV), thorium(IV) and dioxouranium(VI)

International Nuclear Information System (INIS)

Dash, K.C.

1989-01-01

The systematic liquid-liquid extraction behaviour of oxozirconium (IV), thorium(IV) and dioxouranium(VI) have been investigated using a number of synthesised and commercial chelating extractants. The synergism or antagonism for these processes in presence of neutral donor ligands have also been identified and the conditions for separation and isolation of pure individual metal ions have been established. The coordination behaviour of oxozirconium(IV), thorium(IV) and dioxouranium(VI) with a large number of mono- and polydentate ligands have been studied. With oxozirconium(IV), invariably always a cyclic, tetranuclear species is obtained, derived from the tetrameric structure of the parent ZrOCl 2 .8H 2 O which is actually (Zr 4 (OH) 8 (H 2 O) 16 )Cl 8 .12H 2 O. No simple, monomeric oxozirconium(IV) complex was obtained. Uranium(VI) and thorium(IV) form a wide variety of complexes of higher coordination numbers and several bi- and trinuclear complexes were also characterised where the two adjacent metal centres are joined to each other by a double hydroxo-bridge. (author). 69 refs., 3 figs., 4 tabs

Effect of chondrocyte-derived early extracellular matrix on chondrogenesis of placenta-derived mesenchymal stem cells.

Science.gov (United States)

Park, Yong-Beom; Seo, Sinji; Kim, Jin-A; Heo, Jin-Chul; Lim, Young-Cheol; Ha, Chul-Won

2015-06-24

The extracellular matrix (ECM) surrounding cells contains a variety of proteins that provide structural support and regulate cellular functions. Previous studies have shown that decellularized ECM isolated from tissues or cultured cells can be used to improve cell differentiation in tissue engineering applications. In this study we evaluated the effect of decellularized chondrocyte-derived ECM (CDECM) on the chondrogenesis of human placenta-derived mesenchymal stem cells (hPDMSCs) in a pellet culture system. After incubation with or without chondrocyte-derived ECM in chondrogenic medium for 1 or 3 weeks, the sizes and wet masses of the cell pellets were compared with untreated controls (hPDMSCs incubated in chondrogenic medium without chondrocyte-derived ECM). In addition, histologic analysis of the cell pellets (Safranin O and collagen type II staining) and quantitative reverse transcription-PCR analysis of chondrogenic markers (aggrecan, collagen type II, and SOX9) were carried out. Our results showed that the sizes and masses of hPDMSC pellets incubated with chondrocyte-derived ECM were significantly higher than those of untreated controls. Differentiation of hPDMSCs (both with and without chondrocyte-derived ECM) was confirmed by Safranin O and collagen type II staining. Chondrogenic marker expression and glycosaminoglycan (GAG) levels were significantly higher in hPDMSC pellets incubated with chondrocyte-derived ECM compared with untreated controls, especially in cells precultured with chondrocyte-derived ECM for 7 d. Taken together, these results demonstrate that chondrocyte-derived ECM enhances the chondrogenesis of hPDMSCs, and this effect is further increased by preculture with chondrocyte-derived ECM. This preculture method for hPDMSC chondrogenesis represents a promising approach for cartilage tissue engineering.

C-peptide prevents SMAD3 binding to alpha promoters to inhibit collagen type IV synthesis.

Science.gov (United States)

Li, Yanning; Zhong, Yan; Gong, Wenjian; Gao, Xuehan; Qi, Huanli; Liu, Kun; Qi, Jinsheng

2018-07-01

Activation of transforming growth factor β1 (TGFB1)/SMAD3 signaling may lead to additional synthesis of collagen type IV (COL4), which is a major contributor to extracellular matrix (ECM) accumulation in diabetic nephropathy (DN). C-peptide can attenuate fibrosis to have unique beneficial effects in DN. However, whether and how C-peptide affects TGFB1/SMAD3-activated COL4 synthesis is unclear. In this study, pathological changes, expression of COL4 a1-a5 chains ( Col4a1-a5 ), COL4 distribution and protein and TGFB1 and SMAD3 protein were first assessed in a rat model of diabetes. Then, rat mesangial cells were treated with high glucose (HG) and/or C-peptide to investigate the underlying mechanism. Col4a1-a5 expression, COL4 protein and secretion, TGFB1 protein, SMAD3 nuclear translocation and binding of SMAD3 to its cognate sites in the promoters of Col4a1a2 , Col4a3a4 and Col4a5 were measured. It was found that C-peptide attenuated glomerular pathological changes and suppressed renal Col4a1 -a5 mRNA expression, COL4 protein content and TGFB1 protein content. C-peptide had a dose-dependent effect to inhibit Col4a1-a5 mRNA expression, COL4 protein content and secretion, in HG-stimulated mesangial cells. In addition, the HG-induced increase in TGFB1 protein content was significantly reduced by C-peptide. Although not apparently affecting SMAD3 nuclear translocation, C-peptide prevented SMAD3 from binding to its sites in the Col4a1a2 , Col4a3a4 and Col4a5 promoters in HG-stimulated mesangial cells. In conclusion, C-peptide could prevent SMAD3 from binding to its sites in the Col4a1a2 , Col4a3a4 and Col4a5 promoters, to inhibit COL4 generation. These results may provide a mechanism for the alleviation of fibrosis in DN by C-peptide. © 2018 Society for Endocrinology.

Optimal construction and delivery of dual-functioning lentiviral vectors for type I collagen-suppressed chondrogenesis in synovium-derived mesenchymal stem cells.

Science.gov (United States)

Zhang, Feng; Yao, Yongchang; Zhou, Ruijie; Su, Kai; Citra, Fudiman; Wang, Dong-An

2011-06-01

This study aims to deliver both transforming growth factor β3 (TGF-β3) and shRNA targeting type I collagen (Col I) by optimal construction and application of various dual-functioning lentiviral vectors to induce Col I-suppressed chondrogenesis in synovium-derived mesenchymal stem cells (SMSCs). We constructed four lentiviral vectors (LV-1, LV-2, LV-3 and LV-4) with various arrangements of the two expression cassettes in different positions and orientations. Col I inhibition efficiency and chondrogenic markers were assessed with qPCR, ELISA and staining techniques. Among the four vectors, LV-1 has two distant and reversely oriented cassettes, LV-2 has two distant and same-oriented cassettes, LV-3 has two proximal and reversely oriented cassettes, and LV-4 has two proximal and same-oriented cassettes. Col I and chondrogenic markers, including type II collagen (Col II), aggrecan and glycosaminoglycan (GAG), were examined in SMSCs cultured in 3-D alginate hydrogel. All of the four vectors showed distinct effects in Col I level as well as diverse inductive efficiencies in upregulation of the cartilaginous markers. Based on real-time PCR results, LV-1 was optimal towards Col I-suppressed chondrogenesis. LV-1 vector is competent to promote Col I-suppressed chondrogenesis in SMSCs.

Diagnostic Classification of Eating Disorders in Children and Adolescents: How Does DSM-IV-TR Compare to Empirically-Derived Categories?

Science.gov (United States)

Eddy, Kamryn T.; Le Grange, Daniel; Crosby, Ross D.; Hoste, Renee Rienecke; Doyle, Angela Celio; Smyth, Angela; Herzog, David B.

2010-01-01

Objective: The purpose of this study was to empirically derive eating disorder phenotypes in a clinical sample of children and adolescents using latent profile analysis (LPA), and to compare these latent profile (LP) groups to the DSM-IV-TR eating disorder categories. Method: Eating disorder symptom data collected from 401 youth (aged 7 through 19…

Collagen fiber alignment and biaxial mechanical behavior of porcine urinary bladder derived extracellular matrix

NARCIS (Netherlands)

Gilbert, Thomas W.; Wognum, Silvia; Joyce, Erinn M.; Freytes, Donald O.; Sacks, Michael S.; Badylak, Stephen F.

2008-01-01

The collagen fiber alignment and biomechanical behavior of naturally occurring extracellular matrix (ECM) scaffolds are important considerations for the design of medical devices from these materials. Both should be considered in order to produce a device to meet tissue specific mechanical

Quantitative analysis of the synthesis and secretion of type VII collagen in cultured human dermal fibroblasts with a sensitive sandwich enzyme-linked immunoassay.

Science.gov (United States)

Amano, Satoshi; Ogura, Yuki; Akutsu, Nobuko; Nishiyama, Toshio

2007-02-01

Type VII collagen is the major component of anchoring fibrils in the epidermal basement membrane. Its expression has been analyzed by immunostaining or Northern blotting, but rarely at the protein level. In this study, we have quantitatively examined the effects of ascorbic acid and various cytokines/growth factors on the protein synthesis and secretion of type VII collagen by human dermal fibroblasts in culture, using a developed, highly sensitive sandwich enzyme-linked immunoassay with two kinds of specific monoclonal antibodies against the non-collagenous domain-1. Ascorbic acid and its derivative induced a twofold increase in type VII collagen synthesis, and markedly increased the secretion of type VII collagen into the medium when compared with the control culture. This effect was not influenced by the presence of transforming growth factor-beta1 (TGF-beta1). The synthesis of type VII collagen was elevated by TGF-beta1, platelet-derived growth factor, tumor necrosis factor-alpha, and interleukin-1beta, but not by TGF-alpha. Thus, our data indicate that the synthesis and secretion of type VII collagen in human dermal fibroblasts are regulated by ascorbate and the enhancement of type VII collagen gene expression by cytokines/growth factors is accompanied with elevated production of type VII collagen at the protein level.

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...

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.

Evaluation of a dental pulp-derived cell sheet cultured on amniotic membrane substrate.

Science.gov (United States)

Honjo, Ken-ichi; Yamamoto, Toshiro; Adachi, Tetsuya; Amemiya, Takeshi; Mazda, Osam; Kanamura, Narisato; Kita, Masakazu

2015-01-01

Mesenchymal stem cells (MSC) are transplanted for periodontal tissue regeneration, and the periodontal ligament (PDL) is regenerated using a cultured cell sheet. This cultured cell sheet is prepared using PDL-derived cells, growth factors, and amniotic membrane (AM). Dental pulp (DP)-derived cells can be easily obtained from extracted wisdom teeth, proliferate rapidly, and are less susceptible to bacterial infection than PDL-derived cells. Thus, to prepare a novel cell sheet, DP-derived cells were cultured on AM as a culture substrate for immunohistochemical examination. Wisdom teeth extracted from three adults were cut along the cement-enamel border. DP tissue was collected, minced, and primarily cultured. After three or four passage cultures, DP-derived cells were cultured on AM, followed by hematoxylin-eosin (H-E) and immunofluorescence staining. DP-derived cells cultured on AM formed a layered structure. Cells positive for vimentin, Ki-67, ZO-1, desmoplakin, CD29, 44, 105 or 146, STRO-1, collagen IV or VII or laminin 5 or α5 chain were localized. DP-derived cells proliferated on AM, while retaining the properties of DP, which allowed the cultured cell sheet to be prepared. In addition, the cultured cell sheet contained MSC, which suggests its potential application in periodontal tissue regeneration.

Repair of Avascular Meniscus Tears with Electrospun Collagen Scaffolds Seeded with Human Cells.

Science.gov (United States)

Baek, Jihye; Sovani, Sujata; Glembotski, Nicholas E; Du, Jiang; Jin, Sungho; Grogan, Shawn P; D'Lima, Darryl D

2016-03-01

The self-healing capacity of an injured meniscus is limited to the vascularized regions and is especially challenging in the inner avascular regions. As such, we investigated the use of human meniscus cell-seeded electrospun (ES) collagen type I scaffolds to produce meniscal tissue and explored whether these cell-seeded scaffolds can be implanted to repair defects created in meniscal avascular tissue explants. Human meniscal cells (derived from vascular and avascular meniscal tissue) were seeded on ES scaffolds and cultured. Constructs were evaluated for cell viability, gene expression, and mechanical properties. To determine potential for repair of meniscal defects, human meniscus avascular cells were seeded and cultured on aligned ES collagen scaffolds for 4 weeks before implantation. Surgical defects resembling "longitudinal tears" were created in the avascular zone of bovine meniscus and implanted with cell-seeded collagen scaffolds and cultured for 3 weeks. Tissue regeneration and integration were evaluated by histology, immunohistochemistry, mechanical testing, and magentic resonance imaging. Ex vivo implantation with cell-seeded collagen scaffolds resulted in neotissue that was significantly better integrated with the native tissue than acellular collagen scaffolds or untreated defects. Human meniscal cell-seeded ES collagen scaffolds may therefore be useful in facilitating meniscal repair of avascular meniscus tears.

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

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

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.

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.

Extracellular matrix components expression in human pluripotent stem cell-derived retinal organoids recapitulates retinogenesis in vivo and reveals an important role for IMPG1 and CD44 in the development of photoreceptors and interphotoreceptor matrix.

Science.gov (United States)

Felemban, Majed; Dorgau, Birthe; Hunt, Nicola Claire; Hallam, Dean; Zerti, Darin; Bauer, Roman; Ding, Yuchun; Collin, Joseph; Steel, David; Krasnogor, Natalio; Al-Aama, Jumana; Lindsay, Susan; Mellough, Carla; Lako, Majlinda

2018-05-17

The extracellular matrix (ECM) plays an important role in numerous processes including cellular proliferation, differentiation, migration, maturation, adhesion guidance and axonal growth. To date, there has been no detailed analysis of the ECM distribution during retinal ontogenesis in humans and the functional importance of many ECM components is poorly understood. In this study, the expression of key ECM components in adult mouse and monkey retina, developing and adult human retina and retinal organoids derived from human pluripotent stem cells was studied. Our data indicate that basement membrane ECMs (Fibronectin and Collagen IV) were expressed in Bruch's membrane and the inner limiting membrane of the developing human retina, whilst the hyalectins (Versican and Brevican), cluster of differentiation 44 (CD44), photoreceptor-specific ECMs Interphotoreceptor Matrix Proteoglycan 1 (IMPG1) and Interphotoreceptor Matrix Proteoglycan 2 (IMPG2) were detected in the developing interphotoreceptor matrix (IPM). The expression of IMPG1, Versican and Brevican in the developing IPM was conserved between human developing retina and human pluripotent stem cell-derived retinal organoids. Blocking the action of CD44 and IMPG1 in pluripotent stem cell derived retinal organoids affected the development of photoreceptors, their inner/outer segments and connecting cilia and disrupted IPM formation, with IMPG1 having an earlier and more significant impact. Together, our data suggest an important role for IMPG1 and CD44 in the development of photoreceptors and IPM formation during human retinogenesis. The expression and the role of many extracellular matrix (ECM) components during human retinal development is not fully understood. In this study, expression of key ECM components (Collagen IV, Fibronectin, Brevican, Versican, IMPG1 and IMPG2) was investigated during human retinal ontogenesis. Collagen IV and Fibronectin were expressed in Bruch's membrane; whereas Brevican, Versican

Enhanced Dupuytren's disease fibroblast populated collagen lattice contraction is independent of endogenous active TGF-β2

Directory of Open Access Journals (Sweden)

Howard Jeffrey

2004-11-01

Full Text Available Abstract Background Dupuytren's disease (DD is a debilitating fibro-proliferative disorder of the hand characterized by the appearance of fibrotic lesions (nodules and cords leading to flexion contractures of the fingers and loss of hand function. Although the molecular mechanism of DD is unknown, it has been suggested that transforming growth factor-β2 (TGF-β2 may play an important role in the underlying patho-physiology of the disease. The purpose of this study was to further explore this hypothesis by examining the effects of TGF-β2 on primary cell cultures derived from patient-matched disease and normal palmar fascia tissue using a three-dimensional collagen contraction assay. Methods Fibroblast-populated collagen lattice (FPCL contraction assays using primary cell cultures derived from diseased and control fascia of the same DD patients were studied in response to exogenous TGF-β2 and neutralizing anti-TGF-β2 antibodies. Results Contraction of the FPCLs occurred significantly faster and to a greater extent in disease cells compared to control cells. The addition of TGF-β2 enhanced the rate and degree of collagen contraction in a dose-dependent fashion for both control and diseased cells. Neutralizing anti-TGF-β2 antibodies abolished exogenous TGF-β2 stimulated collagen contraction, but did not inhibit the enhanced basal collagen contraction activity of disease FPCL cultures. Conclusions Although exogenous TGF-β2 stimulated both disease and control FPCL contraction, neutralizing anti-TGF-β2 antibodies did not affect the elevated basal collagen contraction activity of disease FPCLs, suggesting that the differences in the collagen contraction activity of control and disease FPCL cultures are not due to differences in the levels of endogenous TGF-β2 activity.

Electrospun tilapia collagen nanofibers accelerating wound healing via inducing keratinocytes proliferation and differentiation.

Science.gov (United States)

Zhou, Tian; Wang, Nanping; Xue, Yang; Ding, Tingting; Liu, Xin; Mo, Xiumei; Sun, Jiao

2016-07-01

The development of biomaterials with the ability to induce skin wound healing is a great challenge in biomedicine. In this study, tilapia skin collagen sponge and electrospun nanofibers were developed for wound dressing. The collagen sponge was composed of at least two α-peptides. It did not change the number of spleen-derived lymphocytes in BALB/c mice, the ratio of CD4(+)/CD8(+) lymphocytes, and the level of IgG or IgM in Sprague-Dawley rats. The tensile strength and contact angle of collagen nanofibers were 6.72±0.44MPa and 26.71±4.88°, respectively. They also had good thermal stability and swelling property. Furthermore, the nanofibers could significantly promote the proliferation of human keratinocytes (HaCaTs) and stimulate epidermal differentiation through the up-regulated gene expression of involucrin, filaggrin, and type I transglutaminase in HaCaTs. The collagen nanofibers could also facilitate rat skin regeneration. In the present study, electrospun biomimetic tilapia skin collagen nanofibers were succesfully prepared, were proved to have good bioactivity and could accelerate rat wound healing rapidly and effectively. These biological effects might be attributed to the biomimic extracellular matrix structure and the multiple amino acids of the collagen nanofibers. Therefore, the cost-efficient tilapia collagen nanofibers could be used as novel wound dressing, meanwhile effectively avoiding the risk of transmitting animal disease in the future clinical apllication. Copyright © 2016 Elsevier B.V. All rights reserved.

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...

Nanostructural Organization of Naturally Occurring Composites—Part I: Silica-Collagen-Based Biocomposites

Directory of Open Access Journals (Sweden)

Hermann Ehrlich

2008-01-01

Full Text Available Glass sponges, as examples of natural biocomposites, inspire investigations aiming at both a better understanding of biomineralization mechanisms and novel developments in the synthesis of nanostructured biomimetic materials. Different representatives of marine glass sponges of the class Hexactinellida (Porifera are remarkable because of their highly flexible basal anchoring spicules. Therefore, investigations of the biochemical compositions and the micro- and nanostructure of the spicules as examples of naturally structured biomaterials are of fundamental scientific relevance. Here we present a detailed study of the structural and biochemical properties of the basal spicules of the marine glass sponge Monorhaphis chuni. The results show unambiguously that in this glass sponge a fibrillar protein of collagenous nature is the template for the silica mineralization in all silica-containing structural layers of the spicule. The structural similarity and homology of collagens derived from M. chuni spicules to other sponge and vertebrate collagens have been confirmed by us using FTIR, amino acid analysis and mass spectrometric sequencing techniques. We suggest that nanomorphology of silica formed on proteinous structures could be determined as an example of biodirected epitaxial nanodistribution of amorphous silica phase on oriented fibrillar collagen templates. Finally, the present work includes a discussion relating to silica-collagen-based hybrid materials for practical applications as biomaterials.

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....

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

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.

A Mineralized Collagen-Polycaprolactone Composite Promotes Healing of a Porcine Mandibular Defect.

Science.gov (United States)

Weisgerber, Daniel W; Milner, Derek J; Lopez-Lake, Heather; Rubessa, Marcello; Lotti, Sammi; Polkoff, Kathryn; Hortensius, Rebecca A; Flanagan, Colleen L; Hollister, Scott J; Wheeler, Matthew B; Harley, Brendan A C

2018-02-01

A tissue engineering approach to address craniofacial defects requires a biomaterial that balances macro-scale mechanical stiffness and strength with the micron-scale features that promote cell expansion and tissue biosynthesis. Such criteria are often in opposition, leading to suboptimal mechanical competence or bioactivity. We report the use of a multiscale composite biomaterial that integrates a polycaprolactone (PCL) reinforcement structure with a mineralized collagen-glycosaminoglycan scaffold to circumvent conventional tradeoffs between mechanics and bioactivity. The composite promotes activation of the canonical bone morphogenetic protein 2 (BMP-2) pathway and subsequent mineralization of adipose-derived stem cells in the absence of supplemental BMP-2 or osteogenic media. We subsequently examined new bone infill in the acellular composite, scaffold alone, or PCL support in 10 mm dia. ramus mandibular defects in Yorkshire pigs. We report an analytical approach to quantify radial, angular, and depth bone infill from micro-computed tomography data. The collagen-PCL composite showed improved overall infill, and significantly increased radial and angular bone infill versus the PCL cage alone. Bone infill was further enhanced in the composite for defects that penetrated the medullary cavity, suggesting recruitment of marrow-derived cells. These results indicate a multiscale mineralized collagen-PCL composite offers strategic advantages for regenerative repair of craniofacial bone defects.

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

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.

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.

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.

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.

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.

Fibroblast Activation Protein (FAP) Accelerates Collagen Degradation and Clearance from Lungs in Mice*

Science.gov (United States)

Fan, Ming-Hui; Zhu, Qiang; Li, Hui-Hua; Ra, Hyun-Jeong; Majumdar, Sonali; Gulick, Dexter L.; Jerome, Jacob A.; Madsen, Daniel H.; Christofidou-Solomidou, Melpo; Speicher, David W.; Bachovchin, William W.; Feghali-Bostwick, Carol; Puré, Ellen

2016-01-01

Idiopathic pulmonary fibrosis is a disease characterized by progressive, unrelenting lung scarring, with death from respiratory failure within 2–4 years unless lung transplantation is performed. New effective therapies are clearly needed. Fibroblast activation protein (FAP) is a cell surface-associated serine protease up-regulated in the lungs of patients with idiopathic pulmonary fibrosis as well as in wound healing and cancer. We postulate that FAP is not only a marker of disease but influences the development of pulmonary fibrosis after lung injury. In two different models of pulmonary fibrosis, intratracheal bleomycin instillation and thoracic irradiation, we find increased mortality and increased lung fibrosis in FAP-deficient mice compared with wild-type mice. Lung extracellular matrix analysis reveals accumulation of intermediate-sized collagen fragments in FAP-deficient mouse lungs, consistent with in vitro studies showing that FAP mediates ordered proteolytic processing of matrix metalloproteinase (MMP)-derived collagen cleavage products. FAP-mediated collagen processing leads to increased collagen internalization without altering expression of the endocytic collagen receptor, Endo180. Pharmacologic FAP inhibition decreases collagen internalization as expected. Conversely, restoration of FAP expression in the lungs of FAP-deficient mice decreases lung hydroxyproline content after intratracheal bleomycin to levels comparable with that of wild-type controls. Our findings indicate that FAP participates directly, in concert with MMPs, in collagen catabolism and clearance and is an important factor in resolving scar after injury and restoring lung homeostasis. Our study identifies FAP as a novel endogenous regulator of fibrosis and is the first to show FAP's protective effects in the lung. PMID:26663085

Identification of novel dipeptidyl peptidase IV (DPP-IV) inhibitory peptides in camel milk protein hydrolysates.

Science.gov (United States)

Nongonierma, Alice B; Paolella, Sara; Mudgil, Priti; Maqsood, Sajid; FitzGerald, Richard J

2018-04-01

Nine novel dipeptidyl peptidase IV (DPP-IV) inhibitory peptides (FLQY, FQLGASPY, ILDKEGIDY, ILELA, LLQLEAIR, LPVP, LQALHQGQIV, MPVQA and SPVVPF) were identified in camel milk proteins hydrolysed with trypsin. This was achieved using a sequential approach combining liquid chromatography tandem mass spectrometry (LC-MS/MS), qualitative/quantitative structure activity relationship (QSAR) and confirmatory studies with synthetic peptides. The most potent camel milk protein-derived DPP-IV inhibitory peptides, LPVP and MPVQA, had DPP-IV half maximal inhibitory concentrations (IC 50 ) of 87.0 ± 3.2 and 93.3 ± 8.0 µM, respectively. DPP-IV inhibitory peptide sequences identified within camel and bovine milk protein hydrolysates generated under the same hydrolysis conditions differ. This was linked to differences in enzyme selectivity for peptide bond cleavage of camel and bovine milk proteins as well as dissimilarities in their amino acid sequences. Camel milk proteins contain novel DPP-IV inhibitory peptides which may play a role in the regulation of glycaemia in humans. Copyright © 2017 Elsevier Ltd. All rights reserved.

Limitations of using aggrecan and type X collagen as markers of chondrogenesis in mesenchymal stem cell differentiation.

Science.gov (United States)

Mwale, Fackson; Stachura, Dorothy; Roughley, Peter; Antoniou, John

2006-08-01

The study was initially designed to differentiate human bone marrow-derived mesenchymal stem cells (MSC) into chondrocyte-like cells, for use in tissue engineering. We cultured MSCs in defined chondrogenic medium as pellet cultures supplemented with transforming growth factor (TGF)-beta1 or -beta3 and dexamethazone, as they are commonly used to promote in vitro chondrogenesis. Markers of chondrogenesis used were type II collagen and aggrecan, with type X collagen being used as a marker of late-stage chondrocyte hypertrophy (associated with endochondral ossification). Our results show that aggrecan is constitutively expressed by MSCs and that type X collagen is expressed as an early event. Furthermore, we found that type X collagen was expressed before type II collagen in some cases. This is surprising because it is understood that stem cells have to be differentiated into chondrocytes before they can become hypertrophic. Thus, caution must be exercised when using aggrecan and type X collagen as markers for chondrogenesis and chondrocyte hypertrophy, respectively, in association with stem cell differentiation from this source.

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...

Chondrogenic properties of collagen type XI, a component of cartilage extracellular matrix.

Science.gov (United States)

Li, Ang; Wei, Yiyong; Hung, Clark; Vunjak-Novakovic, Gordana

2018-08-01

Cartilage extracellular matrix (ECM) has been used for promoting tissue engineering. However, the exact effects of ECM on chondrogenesis and the acting mechanisms are not well understood. In this study, we investigated the chondrogenic effects of cartilage ECM on human mesenchymal stem cells (MSCs) and identified the contributing molecular components. To this end, a preparation of articular cartilage ECM was supplemented to pellets of chondrogenically differentiating MSCs, pellets of human chondrocytes, and bovine articular cartilage explants to evaluate the effects on cell proliferation and the production of cartilaginous matrix. Selective enzymatic digestion and screening of ECM components were conducted to identify matrix molecules with chondrogenic properties. Cartilage ECM promoted MSC proliferation, production of cartilaginous matrix, and maturity of chondrogenic differentiation, and inhibited the hypertrophic differentiation of MSC-derived chondrocytes. Selective digestion of ECM components revealed a contributory role of collagens in promoting chondrogenesis. The screening of various collagen subtypes revealed strong chondrogenic effect of collagen type XI. Finally, collagen XI was found to promote production and inhibit degradation of cartilage matrix in human articular chondrocyte pellets and bovine articular cartilage explants. Our results indicate that cartilage ECM promotes chondrogenesis and inhibits hypertrophic differentiation in MSCs. Collagen type XI is the ECM component that has the strongest effects on enhancing the production and inhibiting the degradation of cartilage matrix. Copyright © 2018 Elsevier Ltd. All rights reserved.

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.

Surgical pitfalls in patients with Ehlers–Danlos type IV: A case of spontaneous sigmoid perforation in a 17-year-old male

Directory of Open Access Journals (Sweden)

Kai Lyn Ng

2011-07-01

Full Text Available Ehlers–Danlos syndrome (EDS is a group of well described connective tissue disorders in which collagen production is impaired. The surgical management of affected individuals remains challenging, with no general consensus. We report a case of spontaneous sigmoid perforation in a 17-year-old Eurasian male, in whom we subsequently established the diagnosis of EDS type IV (EDS-IV. We review the literature to discuss the clinical features and diagnosis, and the recommended therapeutic management.

Collagen cross-linking by adipose-derived mesenchymal stromal cells and scar-derived mesenchymal cells: Are mesenchymal stromal cells involved in scar formation?

NARCIS (Netherlands)

Bogaerdt, van den A.J.; Veen, van der A.G.; Zuijlen, van P.P.; Reijnen, L.; Verkerk, M.; Bank, R.A.; Middelkoop, E.; Ulrich, M.

2009-01-01

In this work, different fibroblast-like (mesenchymal) cell populations that might be involved in wound healing were characterized and their involvement in scar formation was studied by determining collagen synthesis and processing. Depending on the physical and mechanical properties of the tissues,

Collagen cross-linking by adipose-derived mesenchymal stromal cells and scar-derived mesenchymal cells : Are mesenchymal stromal cells involved in scar formation?

NARCIS (Netherlands)

van den Bogaerdt, Antoon J.; van der Veen, Vincent C.; van Zuijlen, Paul P. M.; Reijnen, Linda; Verkerk, Michelle; Bank, Ruud A.; Middelkoop, Esther; Ulrich, Magda M. W.

2009-01-01

In this work, different fibroblast-like (mesenchymal) cell populations that might be involved in wound healing were characterized and their involvement in scar formation was studied by determining collagen synthesis and processing. Depending on the physical and mechanical properties of the tissues,

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.

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....

Chemical structure, biosynthesis and synthesis of free and glycosylated pyridinolines formed by cross-link of bone and synovium collagen.

Science.gov (United States)

Anastasia, Luigi; Rota, Paola; Anastasia, Mario; Allevi, Pietro

2013-09-21

This review focuses on the chemical structure, biosynthesis and synthesis of free and glycosylated pyridinolines (Pyds), fluorescent collagen cross-links, with a pyridinium salt structure. Pyds derive from the degradation of bone collagen and have attracted attention for their use as biochemical markers of bone resorption and to assess fracture risk prediction in persons suffering from osteoporosis, bone cancer and other bone or collagen diseases. We consider and critically discuss all reported syntheses of free and glycosylated Pyds evidencing an unrevised chemistry, original and of general utility, analysis of which allows us to also support a previously suggested non-enzymatic formation of Pyds in collagen better rationalizing and justifying the chemical events.

Effects of extracellular matrix proteins on macrophage differentiation, growth, and function: comparison of liquid and agar culture systems

Science.gov (United States)

Armstrong, J. W.; Chapes, S. K.; Spooner, B. S. (Principal Investigator)

1994-01-01

Both spaceflight and skeletal unloading suppress the haematopoietic differentiation of macrophages (Sonnenfeld et al., Aviat. Space Environ. Med., 61:648-653, 1990; Armstrong et al., J. Appl. Physiol., 75:2734-2739, 1993). The mechanism behind this reduction in haematopoiesis has yet to be elucidated. However, changes in bone marrow extracellular matrix (ECM) may be involved. To further understand the role of ECM products in macrophage differentiation, we have performed experiments evaluating the effects of fibronectin, laminin, collagen type I, and collagen type IV on macrophage development and function. Bone marrow-derived macrophages cultured on four different ECM substrates in liquid culture medium showed less growth than those cultured on plastic. Significant morphological differences were seen on each of the substrates used. Phenotypically and functionally, as measured by class II major histocompatibility molecule (MHCII) expression, MAC-2 expression, and the secretion of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha), these macrophages were similar. In contrast, bone marrow-derived macrophages cultured in suspension, using agar, showed no difference in growth when exposed to ECM proteins. However, IL-6 and TNF-alpha secretion was affected by fibronectin, laminin, collagen type I, and collagen type IV in a concentration-dependent manner. We conclude that the ECM products fibronectin, laminin, collagen type I, and collagen type IV have profound effects on macrophage development and function. Additionally, we suggest that an ECM-supplemented agar culture system provides an environment more analogous to in vivo bone marrow than does a traditional liquid culture system.

Market opportunities: U.S. - PADD IV

International Nuclear Information System (INIS)

Garner, R.P.

1997-01-01

The current supply and demand balance, the short and long term expectations and marketing opportunities for Canadian crude oil in PADD IV, the Rocky Mountain region in the US, were reviewed. It was suggested that market opportunities in PADD IV are derived from the following four factors: (1) crude oil declines within that area, (2) federal regulations, (3) competitive presence with markets, and (4) population growth. The overall conclusion was that Canadian producers and PADD IV refiners will be looking at an ever-growing relationship based on freight equalized world crude prices. 8 tabs., 5 figs

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.

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

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.

A BMP responsive transcriptional region in the chicken type X collagen gene.

Science.gov (United States)

Volk, S W; Luvalle, P; Leask, T; Leboy, P S

1998-10-01

Bone morphogenetic proteins (BMPs) were originally identified by their ability to induce ectopic bone formation and have been shown to promote both chondrogenesis and chondrocyte hypertrophy. BMPs have recently been found to activate a membrane serine/threonine kinase signaling mechanism in a variety of cell types, but the downstream effectors of BMP signaling in chondrocyte differentiation remain unidentified. We have previously reported that BMP-2 markedly stimulates type X collagen expression in prehypertrophic chick sternal chondrocytes, and that type X collagen mRNA levels in chondrocytes cultured under serum-free (SF) conditions are elevated 3- to 5-fold within 24 h. To better define the molecular mechanisms of induction of chondrocyte hypertrophy by BMPs, we examined the effect of BMPs on type X collagen production by 15-day chick embryo sternal chondrocytes cultured under SF conditions in the presence or absence of 30 ng/ml BMP-2, BMP-4, or BMP-7. Two populations of chondrocytes were used: one representing resting cartilage isolated from the caudal third of the sterna and the second representing prehypertrophic cartilage from the cephalic third of the sterna. BMP-2, BMP-4, and BMP-7 all effectively promoted chondrocyte maturation of cephalic sternal chondrocytes as measured by high levels of alkaline phosphatase, diminished levels of type II collagen, and induction of the hypertrophic chondrocyte-specific marker, type X collagen. To test whether BMP control of type X collagen expression occurs at the transcriptional level, we utilized plasmid constructs containing the chicken collagen X promoter and 5' flanking regions fused to a reporter gene. Constructs were transiently transfected into sternal chondrocytes cultured under SF conditions in the presence or absence of 30 ng/ml BMP-2, BMP-4, or BMP-7. A 533 bp region located 2.4-2.9 kb upstream from the type X collagen transcriptional start site was both necessary and sufficient for strong BMP responsiveness

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

Type IV Ehlers-Danlos Syndrome: A Surgical Emergency? A Case of Massive Retroperitoneal Hemorrhage

Science.gov (United States)

Chun, Stephen G; Pedro, Patrick; Yu, Mihae; Takanishi, Danny M

2011-01-01

Retroperitoneal hemorrhagic bleeding is a known manifestation of Type-IV Ehlers-Danlos Syndrome that is caused by loss-of-function mutations of the pro-alpha-1 chains of type III pro-collagen (COL3A1) resulting in vascular fragility. A number of previous reports describe futile surgical intervention for retroperitoneal bleeding in Type-IV Ehlers-Danlos Syndrome with high post-operative mortality, although the rarity of retroperitoneal bleeding associated with Type-IV Ehlers-Danlos Syndrome precludes an evidence-based approach to clinical management. We report a 23-year-old male with history of Type-IV Ehlers-Danlos Syndrome who presented with severe abdominal pain and tachycardia following an episode of vomiting. Further work-up of his abdominal pain revealed massive retroperitoneal bleeding by CT-scan of the abdomen. Given numerous cases of catastrophic injury caused by surgical intervention in Type-IV Ehlers-Danlos Syndrome, the patient was treated non-operatively, and the patient made a full recovery. This case suggests that even in cases of large retroperitoneal hemorrhages associated with Ehlers-Danlos Syndrome, it may not truly represent a surgical emergency. PMID:21966332

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.

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...

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.

Preparation of some complexes of Th(IV) and U(IV) with tetradentate Schiff bases. The crystal structure of bis(N,N'-ethylenebis(3-methoxysalicylaldiminato)) thorium(IV) monopyridine

Energy Technology Data Exchange (ETDEWEB)

Hill, R J; Rickard, C E.F.; White, H E [Auckland Univ. (New Zealand). Dept. of Chemistry

1981-01-01

Complexes of Th(IV) and U(IV) with tetradentate Schiff bases derived from substituted salicylaldehydes have been prepared and characterised. The structure of bis(N,N'-ethylenebis(3-methoxysalicylaldiminato)) Th(IV) monopyridine has been determined by X-ray crystallographic methods. The crystals are triclinic, a = 13.468, b = 9.932, c = 16.552 A, ..cap alpha.. = 91.74, ..beta.. = 94.69, ..gamma.. = 93.03/sup 0/, space group P/sub 1//sup -/. The molecules are eight coordinate with a slightly distorted dodecahedral geometry with the imine nitrogen atoms in the dodecahedral A sites. The pyridine molecule is uncoordinated and functions in a space-filling role.

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).

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.

Preparation and characterization of collagen/PLA, chitosan/PLA, and collagen/chitosan/PLA hybrid scaffolds for cartilage tissue engineering.

Science.gov (United States)

Haaparanta, Anne-Marie; Järvinen, Elina; Cengiz, Ibrahim Fatih; Ellä, Ville; Kokkonen, Harri T; Kiviranta, Ilkka; Kellomäki, Minna

2014-04-01

In this study, three-dimensional (3D) porous scaffolds were developed for the repair of articular cartilage defects. Novel collagen/polylactide (PLA), chitosan/PLA, and collagen/chitosan/PLA hybrid scaffolds were fabricated by combining freeze-dried natural components and synthetic PLA mesh, where the 3D PLA mesh gives mechanical strength, and the natural polymers, collagen and/or chitosan, mimic the natural cartilage tissue environment of chondrocytes. In total, eight scaffold types were studied: four hybrid structures containing collagen and/or chitosan with PLA, and four parallel plain scaffolds with only collagen and/or chitosan. The potential of these types of scaffolds for cartilage tissue engineering applications were determined by the analysis of the microstructure, water uptake, mechanical strength, and the viability and attachment of adult bovine chondrocytes to the scaffolds. The manufacturing method used was found to be applicable for the manufacturing of hybrid scaffolds with highly porous 3D structures. All the hybrid scaffolds showed a highly porous structure with open pores throughout the scaffold. Collagen was found to bind water inside the structure in all collagen-containing scaffolds better than the chitosan-containing scaffolds, and the plain collagen scaffolds had the highest water absorption. The stiffness of the scaffold was improved by the hybrid structure compared to plain scaffolds. The cell viability and attachment was good in all scaffolds, however, the collagen hybrid scaffolds showed the best penetration of cells into the scaffold. Our results show that from the studied scaffolds the collagen/PLA hybrids are the most promising scaffolds from this group for cartilage tissue engineering.

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)

Platelet-derived Growth-factor-releasing Aligned Collagen-nanoparticle Fibers Promote the Proliferation and Tenogenic Differentiation of Adipose-derived Stem Cells

Science.gov (United States)

2013-11-27

among the most common ortho- pedic injuries to soldiers due to repeated exercise , heavy-duty work and battlefield injuries [1,2]. Tendon /ligament...longer, sustained effect on cells. This is highly desirable because tendons /ligaments tend to need a longer time to healing due to the lack of...C). A rat Achilles tendon can sustain a maximum force of 32 N. Depending on the outcome of mechanical evaluation, the aligned collagen fiber scaffold

Culture of hESC-derived pancreatic progenitors in alginate-based scaffolds.

Science.gov (United States)

Formo, Kjetil; Cho, Candy H-H; Vallier, Ludovic; Strand, Berit L

2015-12-01

The effect of alginate-based scaffolds with added basement membrane proteins on the in vitro development of hESC-derived pancreatic progenitors was investigated. Cell clusters were encapsulated in scaffolds containing the basement membrane proteins collagen IV, laminin, fibronectin, or extracellular matrix-derived peptides, and maintained in culture for up to 46 days. The cells remained viable throughout the experiment with no signs of central necrosis. Whereas nonencapsulated cells aggregated into larger clusters, some of which showed signs of morphological changes and tissue organization, the alginate matrix stabilized the cluster size and displayed more homogeneous cell morphologies, allowing culture for long periods of time. For all conditions tested, a stable or declining expression of insulin and PDX1 and an increase in glucagon and somatostatin over time indicated a progressive reduction in beta cell-related gene expression. Alginate scaffolds can provide a chemically defined, xeno-free and easily scalable alternative for culture of pancreatic progenitors. Although no increase in insulin and PDX1 gene expression after alginate-immobilized cell culture was seen in this study, further optimization of the matrix physicochemical and biological properties and of the medium composition may still be a relevant strategy to promote the stabilization or maturation of stem cell-derived beta cells. © 2015 Wiley Periodicals, Inc.

Inhibition of Wnt/β-catenin signaling by a soluble collagen-derived frizzled domain interacting with Wnt3a and the receptors frizzled 1 and 8.

Directory of Open Access Journals (Sweden)

Ismaïl Hendaoui

Full Text Available The Wnt/β-catenin pathway controls cell proliferation, death and differentiation. Several families of extracellular proteins can antagonize Wnt/β-catenin signaling, including the decoy receptors known as secreted frizzled related proteins (SFRPs, which have a cysteine-rich domain (CRD structurally similar to the extracellular Wnt-binding domain of the frizzled receptors. SFRPs inhibit Wnt signaling by sequestering Wnts through the CRD or by forming inactive complexes with the frizzled receptors. Other endogenous molecules carrying frizzled CRDs inhibit Wnt signaling, such as V3Nter, which is proteolytically derived from the cell surface component collagen XVIII and contains a biologically active frizzled domain (FZC18 inhibiting in vivo cell proliferation and tumor growth in mice. We recently showed that FZC18 expressing cells deliver short-range signals to neighboring cells, decreasing their proliferation in vitro and in vivo through the Wnt/β-catenin signaling pathway. Here, using low concentrations of soluble FZC18 and Wnt3a, we show that they physically interact in a cell-free system. In addition, soluble FZC18 binds the frizzled 1 and 8 receptors' CRDs, reducing cell sensitivity to Wnt3a. Conversely, inhibition of Wnt/β-catenin signaling was partially rescued by the expression of full-length frizzled 1 and 8 receptors, but enhanced by the expression of a chimeric cell-membrane-tethered frizzled 8 CRD. Moreover, soluble, partially purified recombinant FZC18_CRD inhibited Wnt3a-induced β-catenin activation. Taken together, the data indicate that collagen XVIII-derived frizzled CRD shifts Wnt sensitivity of normal cells to a lower pitch and controls their growth.

Cells derived from young bone marrow alleviate renal aging.

Science.gov (United States)

Yang, Hai-Chun; Rossini, Michele; Ma, Li-Jun; Zuo, Yiqin; Ma, Ji; Fogo, Agnes B

2011-11-01

Bone marrow-derived stem cells may modulate renal injury, but the effects may depend on the age of the stem cells. Here we investigated whether bone marrow from young mice attenuates renal aging in old mice. We radiated female 12-mo-old 129SvJ mice and reconstituted them with bone marrow cells (BMC) from either 8-wk-old (young-to-old) or 12-mo-old (old-to-old) male mice. Transfer of young BMC resulted in markedly decreased deposition of collagen IV in the mesangium and less β-galactosidase staining, an indicator of cell senescence. These changes paralleled reduced expression of plasminogen activator inhibitor-1 (PAI-1), PDGF-B (PDGF-B), the transdifferentiation marker fibroblast-specific protein-1 (FSP-1), and senescence-associated p16 and p21. Tubulointerstitial and glomerular cells derived from the transplanted BMC did not show β-galactosidase activity, but after 6 mo, there were more FSP-1-expressing bone marrow-derived cells in old-to-old mice compared with young-to-old mice. Young-to-old mice also exhibited higher expression of the anti-aging gene Klotho and less phosphorylation of IGF-1 receptor β. Taken together, these data suggest that young bone marrow-derived cells can alleviate renal aging in old mice. Direct parenchymal reconstitution by stem cells, paracrine effects from adjacent cells, and circulating anti-aging molecules may mediate the aging of the kidney.

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.

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

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.

Tumor Cell Invasion Can Be Blocked by Modulators of Collagen Fibril Alignment That Control Assembly of the Extracellular Matrix.

Science.gov (United States)

Grossman, Moran; Ben-Chetrit, Nir; Zhuravlev, Alina; Afik, Ran; Bassat, Elad; Solomonov, Inna; Yarden, Yosef; Sagi, Irit

2016-07-15

Abnormal architectures of collagen fibers in the extracellular matrix (ECM) are hallmarks of many invasive diseases, including cancer. Targeting specific stages of collagen assembly in vivo presents a great challenge due to the involvement of various crosslinking enzymes in the multistep, hierarchical process of ECM build-up. Using advanced microscopic tools, we monitored stages of fibrillary collagen assembly in a native fibroblast-derived 3D matrix system and identified anti-lysyl oxidase-like 2 (LOXL2) antibodies that alter the natural alignment and width of endogenic fibrillary collagens without affecting ECM composition. The disrupted collagen morphologies interfered with the adhesion and invasion properties of human breast cancer cells. Treatment of mice bearing breast cancer xenografts with the inhibitory antibodies resulted in disruption of the tumorigenic collagen superstructure and in reduction of primary tumor growth. Our approach could serve as a general methodology to identify novel therapeutics targeting fibrillary protein organization to treat ECM-associated pathologies. Cancer Res; 76(14); 4249-58. ©2016 AACR. ©2016 American Association for Cancer Research.

New diorganotin(IV) derivatives of 7-hydroxycoumarin (umbelliferone) and their adducts with 1,10-phenanthroline

Science.gov (United States)

Nath, Mala; Jairath, Ruchi; Eng, George; Song, Xueqing; Kumar, Ashok

2005-10-01

New diorganotin(IV) derivatives of the general formula R 2Sn(Umb) 2 (where R = n-Bu, n-Oct and Ph; Umb = umbelliferone anion) have been synthesized either by the reaction of R 2SnO with umbelliferone under azeotropic removel of water or by the reaction of R 2SnCl 2 with sodium salt of umbelliferone. Further, the adducts of the general formula R 2Sn(Umb) 2·phen (where R = n-Bu and n-Oct; phen = 1,10-phenanthroline) have also been synthesized by the interaction of R 2Sn(Umb) 2 with 1,10-phenanthroline. The bonding and coordination behavior in these derivatives are discussed on the basis of IR and 119Sn Mössbauer spectroscopic studies in solid state. Their coordination behavior in solution is discussed by the multinuclear ( 1H, 13C and 119Sn) NMR spectral studies. The Mössbauer and IR studies indicate that umbelliferone acts as a monoanionic bidentate ligand in R 2Sn(Umb) 2 coordinating through O(7) and O(1). A distorted octahedral geometry around tin has been proposed for R 2Sn(Umb) 2 as well as for R 2Sn(Umb) 2·phen in solid state. The newly synthesized derivatives have been tested for their anti-inflammatory and cardiovascular activities. The average LD 50 value >1000 mg kg -1 of these compounds indicates their safety margin.

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...

Distinct activities of Bartonella henselae type IV secretion effector proteins modulate capillary-like sprout formation.

Science.gov (United States)

Scheidegger, F; Ellner, Y; Guye, P; Rhomberg, T A; Weber, H; Augustin, H G; Dehio, C

2009-07-01

The zoonotic pathogen Bartonella henselae (Bh) can lead to vasoproliferative tumour lesions in the skin and inner organs known as bacillary angiomatosis and bacillary peliosis. The knowledge on the molecular and cellular mechanisms involved in this pathogen-triggered angiogenic process is confined by the lack of a suitable animal model and a physiologically relevant cell culture model of angiogenesis. Here we employed a three-dimensional in vitro angiogenesis assay of collagen gel-embedded endothelial cell (EC) spheroids to study the angiogenic properties of Bh. Spheroids generated from Bh-infected ECs displayed a high capacity to form sprouts, which represent capillary-like projections into the collagen gel. The VirB/VirD4 type IV secretion system and a subset of its translocated Bartonella effector proteins (Beps) were found to profoundly modulate this Bh-induced sprouting activity. BepA, known to protect ECs from apoptosis, strongly promoted sprout formation. In contrast, BepG, triggering cytoskeletal rearrangements, potently inhibited sprouting. Hence, the here established in vitro model of Bartonella- induced angiogenesis revealed distinct and opposing activities of type IV secretion system effector proteins, which together with a VirB/VirD4-independent effect may control the angiogenic activity of Bh during chronic infection of the vasculature.

Co-morbidity and factor analysis on attention deficit hyperactivity disorder and autism spectrum disorder DSM-IV-derived items

Directory of Open Access Journals (Sweden)

Ahmad Ghanizadeh

2012-01-01

Full Text Available Background: There is a gap in the literature regarding the extent of possible co-occurrence of attention deficit hyperactivity disorder (ADHD and pervasive developmental disorders (PDD. This study aimed to investigate co-occurring of ADHD in children with PDD. Methods: A clinical sample of 68 children with PDD was assessed according to DSM-IV criteria to make ADHD and/ or PDD diagnoses. All the different types of PDD were included. DSM-IV derived criteria for ADHD and PDD were analyzed. An exploratory factor analysis was conducted. Results: the rate of autism, Asperger syndrome, Rett′s disorder, childhood disintegrative disorder and PDD-NOS (not otherwise specified was 55.4%, 16.9%, 3.1%, 3.1%, 21.5%, respectively. 53.8% of the sample was with ADHD co-morbidity. The rate of ADHD subtypes was 37.1%, 22.9%, and 40.0% for inattentive type, hyperactivity/impulsivity type and combined type, respectively. Conclusion: ADHD and its symptoms highly co-occur with PDD. Meanwhile, the result of factor analysis supports the independence of ADHD and PDD diagnostic criteria.

Delphinidin prevents high glucose-induced cell proliferation and collagen synthesis by inhibition of NOX-1 and mitochondrial superoxide in mesangial cells

Directory of Open Access Journals (Sweden)

Seung Eun Song

2016-04-01

Full Text Available This study examined the effect of delphinidin on high glucose-induced cell proliferation and collagen synthesis in mesangial cells. Glucose dose-dependently (5.6–25 mM increased cell proliferation and collagen I and IV mRNA levels, whereas pretreatment with delphinidin (50 μM prevented cell proliferation and the increased collagen mRNA levels induced by high glucose (25 mM. High glucose increased reactive oxygen species (ROS generation, and this was suppressed by pretreating delphinidin or the antioxidant N-acetyl cysteine. NADPH oxidase (NOX 1 was upregulated by high glucose, but pretreatment with delphinidin abrogated this upregulation. Increased mitochondrial superoxide by 25 mM glucose was also suppressed by delphinidin. The NOX inhibitor apocynin and mitochondria-targeted antioxidant Mito TEMPO inhibited ROS generation and cell proliferation induced by high glucose. Phosphorylation of extracellular signal regulated kinase (ERK1/2 was increased by high glucose, which was suppressed by delphinidin, apocynin or Mito TEMPO. Furthermore, PD98059 (an ERK1/2 inhibitor prevented the high glucose-induced cell proliferation and increased collagen mRNA levels. Transforming growth factor (TGF-β protein levels were elevated by high glucose, and pretreatment with delphinidin or PD98059 prevented this augmentation. These results suggest that delphinidin prevents high glucose-induced cell proliferation and collagen synthesis by inhibition of NOX-1 and mitochondrial superoxide in mesangial cells.

Dipeptidyl peptidase IV inhibitors derived from a mangrove flora Rhizophora mucronata: An in silico approach

Directory of Open Access Journals (Sweden)

Selvaraj Gurudeeban

2012-08-01

Full Text Available Dipeptidyl peptidase IV (DPP IV is responsible for conversion of glucose tolerance (GLP-1, into inactive form. The inhibition of DPP IV would be beneficial in the treatment of diabetes mellitus. Therefore, the aim of the present study was to isolate and evaluate cystine, phenyl acetic acid, acrylamide, caprylone and oleic acid from Rhizophora mucronata inhibitory action on DPP IV inhibitors using in silico approach. In silico analysis of cystine, phenyl acetic acid, acrylamide, caprylone and oleic acid on human apo DPP IV protein was done by using Autodoc 4.0. Among the five compounds cysteine acts as an inhibitor with binding energy -5.89 kcal/mol, seven hydrogen bond interactions at residues VAL459, VAL 459, GLU408, GLU206, ARG358, GLU205 and SER209 to suppresses the action of DPP IV protein.

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...

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.

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.

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...

Human Bone Derived Collagen for the Development of an Artificial Corneal Endothelial Graft. In Vivo Results in a Rabbit Model.

Directory of Open Access Journals (Sweden)

Natalia Vázquez

Full Text Available Corneal keratoplasty (penetrating or lamellar using cadaveric human tissue, is nowadays the main treatment for corneal endotelial dysfunctions. However, there is a worldwide shortage of donor corneas available for transplantation and about 53% of the world's population have no access to corneal transplantation. Generating a complete cornea by tissue engineering is still a tough goal, but an endothelial lamellar graft might be an easier task. In this study, we developed a tissue engineered corneal endothelium by culturing human corneal endothelial cells on a human purified type I collagen membrane. Human corneal endothelial cells were cultured from corneal rims after corneal penetrating keratoplasty and type I collagen was isolated from remnant cancellous bone chips. Isolated type I collagen was analyzed by western blot, liquid chromatography -mass spectrometry and quantified using the exponentially modified protein abundance index. Later on, collagen solution was casted at room temperature obtaining an optically transparent and mechanically manageable membrane that supports the growth of human and rabbit corneal endothelial cells which expressed characteristic markers of corneal endothelium: zonula ocluddens-1 and Na+/K+ ATPase. To evaluate the therapeutic efficiency of our artificial endothelial grafts, human purified type I collagen membranes cultured with rabbit corneal endothelial cells were transplanted in New Zealand white rabbits that were kept under a minimal immunosuppression regimen. Transplanted corneas maintained transparency for as long as 6 weeks without obvious edema or immune rejection and maintaining the same endothelial markers that in a healthy cornea. In conclusion, it is possible to develop an artificial human corneal endothelial graft using remnant tissues that are not employed in transplant procedures. This artificial endothelial graft can restore the integrality of corneal endothelium in an experimental model of

[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.

LOXL4 knockdown enhances tumor growth and lung metastasis through collagen-dependent extracellular matrix changes in triple-negative breast cancer.

Science.gov (United States)

Choi, Sul Ki; Kim, Hoe Suk; Jin, Tiefeng; Moon, Woo Kyung

2017-02-14

Lysyl oxidase (LOX) family genes catalyze collagen cross-link formation. To determine the effects of lysyl oxidase-like 4 (LOXL4) expression on breast tumor formation and metastasis, we evaluated primary tumor growth and lung metastasis in mice injected with LOXL4-knockdown MDA-MB-231 triple-negative human breast cancer cells. In addition, we analyzed overall survival in breast cancer patients based on LOXL4 expression using a public online database. In the mouse xenograft model, LOXL4 knockdown increased primary tumor growth and lung colonization as well as collagen I and IV, lysine hydroxylase 1 and 2, and prolyl 4-hydroxylase subunit alpha 1 and 2 levels. Second harmonic generation imaging revealed that LOXL4 knockdown resulted in the thickening of collagen bundles within tumors. In addition, weak LOXL4 expression was associated with poor overall survival in breast cancer patients from the BreastMark dataset, and this association was strongest in triple-negative breast cancer patients. These results demonstrate that weak LOXL4 expression leads to remodeling of the extracellular matrix through induction of collagen synthesis, deposition, and structural changes. These alterations in turn promote tumor growth and metastasis and are associated with poor clinical outcomes in triple-negative breast cancer.

Multifunctional role of osteopontin in directing intrafibrillar mineralization of collagen and activation of osteoclasts

Science.gov (United States)

Rodriguez, Douglas E.; Thula-Mata, Taili; Toro, Edgardo J.; Yeh, Ya-Wen; Holt, Carl; Holliday, L. Shannon; Gower, Laurie B.

2013-01-01

Mineralized collagen composites are of interest because they have the potential to provide a bone-like scaffold that stimulates the natural processes of resorption and remodeling. Working toward this goal, our group has previously shown that the nanostructure of bone can be reproduced using a polymer-induced liquid-precursor (PILP) process, which enables intrafibrillar mineralization of collagen with hydroxyapatite (HA) to be achieved. This prior work used polyaspartic acid (pASP), a simple mimic for acidic non-collagenous proteins (NCPs), to generate nanodroplets/nanoparticles of an amorphous mineral precursor which can infiltrate the interstices of type-I collagen fibrils. In this study we show that osteopontin (OPN) can similarly serve as a process-directing agent for the intrafibrillar mineralization of collagen, even though OPN is generally considered a mineralization inhibitor. We also found that inclusion of OPN in the mineralization process promotes the interaction of mouse marrow-derived osteoclasts with PILP-remineralized bone that was previously demineralized, as measured by actin ring formation. While osteoclast activation occurred when pASP was used as the process-directing agent, using OPN resulted in a dramatic effect on osteoclast activation, presumably because of the inherent arginine-glycine-aspartate acid (RGD) ligands of OPN. By capitalizing on the multifunctionality of OPN, these studies may lead the way to producing biomimetic bone substitutes with the capability of tailorable bioresorption rates. PMID:24140612

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

Extracellular matrix collagen alters cell proliferation and cell cycle progression of human uterine leiomyoma smooth muscle cells.

Science.gov (United States)

Koohestani, Faezeh; Braundmeier, Andrea G; Mahdian, Arash; Seo, Jane; Bi, JiaJia; Nowak, Romana A

2013-01-01

Uterine leiomyomas (ULs) are benign tumors occurring in the majority of reproductive aged women. Despite the high prevalence of these tumors, little is known about their etiology. A hallmark of ULs is the excessive deposition of extracellular matrix (ECM), primarily collagens. Collagens are known to modulate cell behavior and function singularly or through interactions with integrins and growth factor-mediated mitogenic pathways. To better understand the pathogenesis of ULs and the role of ECM collagens in their growth, we investigated the interaction of leiomyoma smooth muscle cells (LSMCs) with two different forms of collagen, non-polymerized collagen (monomeric) and polymerized collagen (fibrillar), in the absence or presence of platelet-derived growth factor (PDGF), an abundant growth factor in ULs. Primary cultures of human LSMCS from symptomatic patients were grown on these two different collagen matrices and their morphology, cytoskeletal organization, cellular proliferation, and signaling pathways were evaluated. Our results showed that LSMCs had distinct morphologies on the different collagen matrices and their basal as well as PDGF-stimulated proliferation varied on these matrices. These differences in proliferation were accompanied by changes in cell cycle progression and p21, an inhibitory cell cycle protein. In addition we found alterations in the phosphorylation of focal adhesion kinase, cytoskeletal reorganization, and activation of the mitogen activated protein kinase (MAPK) signaling pathway. In conclusion, our results demonstrate a direct effect of ECM on the proliferation of LSMCs through interplay between the collagen matrix and the PDGF-stimulated MAPK pathway. In addition, these findings will pave the way for identifying novel therapeutic approaches for ULs that target ECM proteins and their signaling pathways in ULs.

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

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....

Mechanisms of Plastic Deformation in Collagen Networks Induced by Cellular Forces.

Science.gov (United States)

Ban, Ehsan; Franklin, J Matthew; Nam, Sungmin; Smith, Lucas R; Wang, Hailong; Wells, Rebecca G; Chaudhuri, Ovijit; Liphardt, Jan T; Shenoy, Vivek B

2018-01-23

Contractile cells can reorganize fibrous extracellular matrices and form dense tracts of fibers between neighboring cells. These tracts guide the development of tubular tissue structures and provide paths for the invasion of cancer cells. Here, we studied the mechanisms of the mechanical plasticity of collagen tracts formed by contractile premalignant acinar cells and fibroblasts. Using fluorescence microscopy and second harmonic generation, we quantified the collagen densification, fiber alignment, and strains that remain within the tracts after cellular forces are abolished. We explained these observations using a theoretical fiber network model that accounts for the stretch-dependent formation of weak cross-links between nearby fibers. We tested the predictions of our model using shear rheology experiments. Both our model and rheological experiments demonstrated that increasing collagen concentration leads to substantial increases in plasticity. We also considered the effect of permanent elongation of fibers on network plasticity and derived a phase diagram that classifies the dominant mechanisms of plasticity based on the rate and magnitude of deformation and the mechanical properties of individual fibers. Plasticity is caused by the formation of new cross-links if moderate strains are applied at small rates or due to permanent fiber elongation if large strains are applied over short periods. Finally, we developed a coarse-grained model for plastic deformation of collagen networks that can be employed to simulate multicellular interactions in processes such as morphogenesis, cancer invasion, and fibrosis. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Fluorescent Hydrogel Generated Conveniently from a Perylene Tetracarboxylate Derivative of Titanium(IV) Alkoxide.

Science.gov (United States)

Zou, Dan-Hong; Wang, Peng; Luo, Wen; Hou, Jin-Le; Zhu, Qin-Yu; Dai, Jie

2018-02-05

Organic gelators and metal-coordination frameworks based on perylene derivatives as functional materials have attracted great attention because of their intense fluorescence emission as well as unique electronic and photonic properties. We report here the structures and properties of a luminescent titanium(IV) coordination compound of a perylene tetracarboxylate (PTC) derivative, [Ti 2 (O i Pr) 6 (L 1 )(phen) 2 ] (1), along with its two naphthalene analogues, [Ti 2 (O i Pr) 6 (L 2 )(phen) 2 ] (2) and [Ti 2 (O i Pr) 6 (L 2 )(bpy) 2 ] (3), where L 1 = 3,9-dicarboxylate-(4,10-diisopropanolcarboxylate)perylene, phen = 1,10-phenanthroline, L 2 = 1,5-dicarboxylate-(2,6-diisopropanolcarboxylate)naphthalene, and bpy = 2,2'-bipyridine. Compound 1 is a rare early-transition-metal PTC coordination compound that can be simply prepared in one pot as crystals by a low-heat synthesis. Unlike those of paramagnetic late-transition-metal PTC compounds, compound 1 showed intense fluorescence emission. More remarkably, the crystals of 1 can be turned immediately to a fluorescent hydrogel just through a simple procedure, putting the crystals in water and then treating with ultrasound. No acid catalyst or pH adjustment is needed. Hydrolysis of the titanium isopropanol group in water and π-π interaction of the perylene and phen play important roles in the gelation process. The film prepared from the gel can be used as a visual fluorescence sensor for aromatic amines and phenols, which are hazards for the human and environment.

Synthesis, characterization and antimicrobial activity of potential bioactive organotin(iv) dithiocarboxylates

International Nuclear Information System (INIS)

Abbas, S.M.; Sirajuddin, M.; Shah, F.A.

2013-01-01

A series of newly synthesized organotin(IV) compounds; Me/sub 2/SnClL (1) Bu2SnClL (2), Ph/sub 2/SnClL (3), Me/sub 3/SnL (4), Ph3SnL (5) have been derived from the reaction of organotin(IV) chlorides with 4-formylpiperazinium 4-formylpiperazine-1-carbodithioate (L) in the appropriate molar ratio. Their spectroscopic investigations have been carried out in solution state. Based on spectroscopic results, the ligand appeared to coordinate to the Sn atom through the CSS moiety. Bioassay results have revealed that these compounds have good antibacterial and antifungal activities and may well be the basis for a new class of antimicrobial drugs. The triorganotin(IV) derivatives in particular, were found to be more active than diorganotin(IV) compounds. (author)

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

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 ...

Collagenous Extracellular Matrix Biomaterials for Tissue Engineering: Lessons from the Common Sea Urchin Tissue

Science.gov (United States)

Goh, Kheng Lim; Holmes, David F.

2017-01-01

Scaffolds for tissue engineering application may be made from a collagenous extracellular matrix (ECM) of connective tissues because the ECM can mimic the functions of the target tissue. The primary sources of collagenous ECM material are calf skin and bone. However, these sources are associated with the risk of having bovine spongiform encephalopathy or transmissible spongiform encephalopathy. Alternative sources for collagenous ECM materials may be derived from livestock, e.g., pigs, and from marine animals, e.g., sea urchins. Collagenous ECM of the sea urchin possesses structural features and mechanical properties that are similar to those of mammalian ones. However, even more intriguing is that some tissues such as the ligamentous catch apparatus can exhibit mutability, namely rapid reversible changes in the tissue mechanical properties. These tissues are known as mutable collagenous tissues (MCTs). The mutability of these tissues has been the subject of on-going investigations, covering the biochemistry, structural biology and mechanical properties of the collagenous components. Recent studies point to a nerve-control system for regulating the ECM macromolecules that are involved in the sliding action of collagen fibrils in the MCT. This review discusses the key attributes of the structure and function of the ECM of the sea urchin ligaments that are related to the fibril-fibril sliding action—the focus is on the respective components within the hierarchical architecture of the tissue. In this context, structure refers to size, shape and separation distance of the ECM components while function is associated with mechanical properties e.g., strength and stiffness. For simplicity, the components that address the different length scale from the largest to the smallest are as follows: collagen fibres, collagen fibrils, interfibrillar matrix and collagen molecules. Application of recent theories of stress transfer and fracture mechanisms in fibre reinforced

Collagenous Extracellular Matrix Biomaterials for Tissue Engineering: Lessons from the Common Sea Urchin Tissue.

Science.gov (United States)

Goh, Kheng Lim; Holmes, David F

2017-04-25

Scaffolds for tissue engineering application may be made from a collagenous extracellular matrix (ECM) of connective tissues because the ECM can mimic the functions of the target tissue. The primary sources of collagenous ECM material are calf skin and bone. However, these sources are associated with the risk of having bovine spongiform encephalopathy or transmissible spongiform encephalopathy. Alternative sources for collagenous ECM materials may be derived from livestock, e.g., pigs, and from marine animals, e.g., sea urchins. Collagenous ECM of the sea urchin possesses structural features and mechanical properties that are similar to those of mammalian ones. However, even more intriguing is that some tissues such as the ligamentous catch apparatus can exhibit mutability, namely rapid reversible changes in the tissue mechanical properties. These tissues are known as mutable collagenous tissues (MCTs). The mutability of these tissues has been the subject of on-going investigations, covering the biochemistry, structural biology and mechanical properties of the collagenous components. Recent studies point to a nerve-control system for regulating the ECM macromolecules that are involved in the sliding action of collagen fibrils in the MCT. This review discusses the key attributes of the structure and function of the ECM of the sea urchin ligaments that are related to the fibril-fibril sliding action-the focus is on the respective components within the hierarchical architecture of the tissue. In this context, structure refers to size, shape and separation distance of the ECM components while function is associated with mechanical properties e.g., strength and stiffness. For simplicity, the components that address the different length scale from the largest to the smallest are as follows: collagen fibres, collagen fibrils, interfibrillar matrix and collagen molecules. Application of recent theories of stress transfer and fracture mechanisms in fibre reinforced

Collagenous Extracellular Matrix Biomaterials for Tissue Engineering: Lessons from the Common Sea Urchin Tissue

Directory of Open Access Journals (Sweden)

Kheng Lim Goh

2017-04-01

Full Text Available Scaffolds for tissue engineering application may be made from a collagenous extracellular matrix (ECM of connective tissues because the ECM can mimic the functions of the target tissue. The primary sources of collagenous ECM material are calf skin and bone. However, these sources are associated with the risk of having bovine spongiform encephalopathy or transmissible spongiform encephalopathy. Alternative sources for collagenous ECM materials may be derived from livestock, e.g., pigs, and from marine animals, e.g., sea urchins. Collagenous ECM of the sea urchin possesses structural features and mechanical properties that are similar to those of mammalian ones. However, even more intriguing is that some tissues such as the ligamentous catch apparatus can exhibit mutability, namely rapid reversible changes in the tissue mechanical properties. These tissues are known as mutable collagenous tissues (MCTs. The mutability of these tissues has been the subject of on-going investigations, covering the biochemistry, structural biology and mechanical properties of the collagenous components. Recent studies point to a nerve-control system for regulating the ECM macromolecules that are involved in the sliding action of collagen fibrils in the MCT. This review discusses the key attributes of the structure and function of the ECM of the sea urchin ligaments that are related to the fibril-fibril sliding action—the focus is on the respective components within the hierarchical architecture of the tissue. In this context, structure refers to size, shape and separation distance of the ECM components while function is associated with mechanical properties e.g., strength and stiffness. For simplicity, the components that address the different length scale from the largest to the smallest are as follows: collagen fibres, collagen fibrils, interfibrillar matrix and collagen molecules. Application of recent theories of stress transfer and fracture mechanisms in fibre

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.

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

Organic derivatives of tin (II/IV): Investigation of their structure

Energy Technology Data Exchange (ETDEWEB)

Szirtes, L., E-mail: szirtes@iki.kfki.h [Institute of Isotopes of the Hungarian Academy of Sciences, Budapest H-1525, P.O. Box 77 (Hungary); Megyeri, J., E-mail: megyeri@iki.kfki.h [Institute of Isotopes of the Hungarian Academy of Sciences, Budapest H-1525, P.O. Box 77 (Hungary); Kuzmann, E. [Laboratory of Nuclear Chemistry, CRC of the Hungarian Academy of Science at Eoetvoes University, H-1518 Budapest, P.O. Box 32 (Hungary); Beck, A. [Institute of Isotopes of the Hungarian Academy of Sciences, Budapest H-1525, P.O. Box 77 (Hungary)

2011-07-15

The structures of tin(II)-oxalate, tin(IV)Na-EDTA and tin(IV)Na{sub 8}-inositol hexaphosphate were investigated using XRD analysis. Samples were identified using the Moessbauer study, thermal analysis and FTIR spectrometry. The Moessbauer study determined two different oxidation states of tin atoms, and consequently two different tin surroundings in the end products. The tin oxalate was found to be orthorhombic with space group Pnma, a=9.2066(3) A, b=9.7590(1) A, c=13.1848(5) A, V=1184.62 A{sup 3} and Z=8. SnNa-EDTA was found to be monoclinic with space group P2{sub 1}/c{sub 1}, a=10.7544(3) A, b=10.1455(3) A, c=16.5130(6) A, {beta}=98.59(2){sup o}, V=1781.50(4) A{sup 3} and Z=4. Sn(C{sub 6}H{sub 6}Na{sub 8}O{sub 24}P{sub 6}) was found to be amorphous.

Disorganized collagen scaffold interferes with fibroblast mediated deposition of organized extracellular matrix in vitro.

Science.gov (United States)

Saeidi, Nima; Guo, Xiaoqing; Hutcheon, Audrey E K; Sander, Edward A; Bale, Shyam Sundar; Melotti, Suzanna A; Zieske, James D; Trinkaus-Randall, Vickery; Ruberti, Jeffrey W

2012-10-01

Many tissue engineering applications require the remodeling of a degradable scaffold either in vitro or in situ. Although inefficient remodeling or failure to fully remodel the temporary matrix can result in a poor clinical outcome, very few investigations have examined in detail, the interaction of regenerative cells with temporary scaffoldings. In a recent series of investigations, randomly oriented collagen gels were directly implanted into human corneal pockets and followed for 24 months. The resulting remodeling response exhibited a high degree of variability which likely reflects differing regenerative/synthetic capacity across patients. Given this variability, we hypothesize that a disorganized, degradable provisional scaffold could be disruptive to a uniform, organized reconstruction of stromal matrix. In this investigation, two established corneal stroma tissue engineering culture systems (collagen scaffold-based and scaffold-free) were compared to determine if the presence of the disorganized collagen gel influenced matrix production and organizational control exerted by primary human corneal fibroblast cells (PHCFCs). PHCFCs were cultured on thin disorganized reconstituted collagen substrate (RCS--five donors: average age 34.4) or on a bare polycarbonate membrane (five donors: average age 32.4 controls). The organization and morphology of the two culture systems were compared over the long-term at 4, 8, and 11/12 weeks. Construct thickness and extracellular matrix organization/alignment was tracked optically with bright field and differential interference contrast (DIC) microscopy. The details of cell/matrix morphology and cell/matrix interaction were examined with standard transmission, cuprolinic blue and quick-freeze/deep-etch electron microscopy. Both the scaffold-free and the collagen-based scaffold cultures produced organized arrays of collagen fibrils. However, at all time points, the amount of organized cell-derived matrix in the scaffold

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)

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...

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.

[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.

Extraction of collagen and gelatine from meat industry by-products for food and non food uses.

Science.gov (United States)

Mokrejs, Pavel; Langmaier, Ferdinand; Mladek, Milan; Janacova, Dagmar; Kolomaznik, Karel; Vasek, Vladimir

2009-02-01

Short tendons of slaughtered cattle, which consist of relatively pure collagen, were cleaned of lipoid substances and non-collagen proteins using a commercial enzymatic preparation. Diluted acetic acid was used to separate the acid-soluble collagen (M(N) approximately 300 kDa) for a yield of around 5%. The residue was extracted with water and the extraction conditions were derived to produce gelatine with a gel rigidity of 350-410 degrees Bloom and a yield of 55-60%. Prolonged extraction time, as well as increased extraction temperature, led to a deterioration in the gelatine quality and, therefore, the residue after aqueous extraction was processed by enzymatic hydrolysis into a collagen hydrolysate of M(N) = 500-1000 Da. Such hydrolysates can be utilized in industry as humectants in cosmetic skin-care preparations or as a secondary industrial raw material for producing surfactants of acylamino-carboxy acid type, which are known for their favourable dermatological effects. Apart from a maximum of 7% lipoid substances the proposed procedure produced no further waste so it may be regarded as a 'clean technology'.

Acceleration of bone union after structural bone grafts with a collagen-binding basic fibroblast growth factor anchored-collagen sheet for critical-size bone defects

International Nuclear Information System (INIS)

Ueno, Masaki; Uchida, Kentaro; Saito, Wataru; Inoue, Gen; Takahira, Naonobu; Takaso, Masashi; Matsushita, Osamu; Yogoro, Mizuki; Nishi, Nozomu; Ogura, Takayuki; Hattori, Shunji; Tanaka, Keisuke

2014-01-01

Bone allografts are commonly used for the repair of critical-size bone defects. However, the loss of cellular activity in processed grafts markedly reduces their healing potential compared with autografts. To overcome this obstacle, we developed a healing system for critical-size bone defects that consists of overlaying an implanted bone graft with a collagen sheet (CS) loaded with basic fibroblast growth factor (bFGF) fused to the collagen-binding domain derived from a Clostridium histolyticum collagenase (CB-bFGF). In a murine femoral defect model, defect sites treated with CS/CB-bFGF had a significantly larger callus volume than those treated with CS/native bFGF. In addition, treatment with CS/CB-bFGF resulted in the rapid formation of a hard callus bridge and a larger total callus volume at the host–graft junction than treatment with CS/bFGF. Our results suggest that the combined use of CS and CB-bFGF helps accelerate the union of allogenic bone grafts. (paper)

Synthesis of new oxovanadium (IV) complexes of potential insulinmimetic activity with coumarin-3-carboxylic acid ligands and substituted derivatives

International Nuclear Information System (INIS)

Salas Fernandez, Paloma; Alvino de la Sota, Nora; Galli Rigo-Righi, Carla

2013-01-01

This work comprises the design and synthesis of four new oxovanadium (IV) complexes, a metal which possesses insulin-mimetic action. Coumarin-3-carboxylic acid and three of its 6 -and 6,8- derivatives were used as ligands. Coumarins are of interest due to their well-known biological properties and pharmacological applications; these include the insulino-sensibilizing effect of certain alcoxy-hydroxy-derivatives which might lead to the eventual existence of a synergetic effect with the active metal center. The synthesis of the vanadyl complexes was preceded by the synthesis of the coumarin-3-carboxylic acid and its 6-bromo- derivative, as well as the syntheses of three derivatives not previously reported: 6-bromo-8-metoxi-, 6-bromo-8-nitro-, and 6-bromo-8-hydroxy-, which were prepared by a Knoevenagel condensation reaction. The complexes, on their part, were prepared by a metathesis reaction between VOSO 4 and the corresponding ligands, on the basis of methods reported for other vanadyl complexes and under strict pH control. The coumarin-3-carboxylic ligands and the derivatives were characterized by 1 H-NMR-, FTIR- and UV-Vis-spectroscopy. In the case of the complexes, their paramagnetic character did not allow for NMR characterization, being thus identified by FT-IR-spectroscopy and by the quantitative determination of their vanadium contents. (author)

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

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.

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...

Monomeric, porous type II collagen scaffolds promote chondrogenic differentiation of human bone marrow mesenchymal stem cells in vitro

Science.gov (United States)

Tamaddon, M.; Burrows, M.; Ferreira, S. A.; Dazzi, F.; Apperley, J. F.; Bradshaw, A.; Brand, D. D.; Czernuszka, J.; Gentleman, E.

2017-03-01

Osteoarthritis (OA) is a common cause of pain and disability and is often associated with the degeneration of articular cartilage. Lesions to the articular surface, which are thought to progress to OA, have the potential to be repaired using tissue engineering strategies; however, it remains challenging to instruct cell differentiation within a scaffold to produce tissue with appropriate structural, chemical and mechanical properties. We aimed to address this by driving progenitor cells to adopt a chondrogenic phenotype through the tailoring of scaffold composition and physical properties. Monomeric type-I and type-II collagen scaffolds, which avoid potential immunogenicity associated with fibrillar collagens, were fabricated with and without chondroitin sulfate (CS) and their ability to stimulate the chondrogenic differentiation of human bone marrow-derived mesenchymal stem cells was assessed. Immunohistochemical analyses showed that cells produced abundant collagen type-II on type-II scaffolds and collagen type-I on type-I scaffolds. Gene expression analyses indicated that the addition of CS - which was released from scaffolds quickly - significantly upregulated expression of type II collagen, compared to type-I and pure type-II scaffolds. We conclude that collagen type-II and CS can be used to promote a more chondrogenic phenotype in the absence of growth factors, potentially providing an eventual therapy to prevent OA.

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

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

FGF-2 potently induces both proliferation and DSP expression in collagen type I gel cultures of adult incisor immature pulp cells

International Nuclear Information System (INIS)

Nakao, Kazuhisa; Itoh, Makoto; Tomita, Yusuke; Tomooka, Yasuhiro; Tsuji, Takashi

2004-01-01

We investigated the effects of both cytokines and extracellular matrices on the proliferation and differentiation of immature adult rat incisor dental pulp cells. These immature cells, which have a high-proliferative potency in vitro and do not express mRNAs for dentin non-collagenous proteins such as dentin sialoprotein (DSP), bone sialoprotein (BSP), and osteocalcin, exist in the root regions of adult rat incisors. Fibroblast growth factor-2 (FGF-2) stimulated the proliferation of these immature cells and the subsequent production of mineralized calcium was induced by β-glycerophosphate treatment. Additionally, FGF-2 dramatically induced the expression of DSP and BSP mRNAs, but only in collagen type I gel cultures, whereas neither plate-coated collagen type I nor fibronectin, laminin or collagen type IV cultures could produce this effect and generate sufficient physiological levels of these transcripts. Although bone morphogenetic protein-4 could not induce the proliferation of immature dental pulp cells nor upregulate DSP mRNA expression, it had a synergistic effect upon DSP transcript levels in conjunction with FGF-2. These results suggest that both the presence of FGF-2 and the three-dimensional formation of immature dental pulp cells in collagen type I gel cultures are essential for both DSP expression and odontoblast differentiation. These observations provide valuable information concerning the study of the commitment and differentiation of odontoblast lineages, and also provide a basis for the rational design of cytokine and extracellular matrix based compounds for regenerative therapies in new dental treatments

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.

Targeting Heparin to Collagen within Extracellular Matrix Significantly Reduces Thrombogenicity and Improves Endothelialization of Decellularized Tissues.

Science.gov (United States)

Jiang, Bin; Suen, Rachel; Wertheim, Jason A; Ameer, Guillermo A

2016-12-12

Thrombosis within small-diameter vascular grafts limits the development of bioartificial, engineered vascular conduits, especially those derived from extracellular matrix (ECM). Here we describe an easy-to-implement strategy to chemically modify vascular ECM by covalently linking a collagen binding peptide (CBP) to heparin to form a heparin derivative (CBP-heparin) that selectively binds a subset of collagens. Modification of ECM with CBP-heparin leads to increased deposition of functional heparin (by ∼7.2-fold measured by glycosaminoglycan composition) and a corresponding reduction in platelet binding (>70%) and whole blood clotting (>80%) onto the ECM. Furthermore, addition of CBP-heparin to the ECM stabilizes long-term endothelial cell attachment to the lumen of ECM-derived vascular conduits, potentially through recruitment of heparin-binding growth factors that ultimately improve the durability of endothelialization in vitro. Overall, our findings provide a simple yet effective method to increase deposition of functional heparin on the surface of ECM-based vascular grafts and thereby minimize thrombogenicity of decellularized tissue, overcoming a significant challenge in tissue engineering of bioartificial vessels and vascularized organs.

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.

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....

[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.

Introduction of the human proα1(I) collagen gene into proα1(I)-deficient Mov-13 mouse cells leads to formation of functional mouse-human hybrid type I collagen

International Nuclear Information System (INIS)

Schnieke, A.; Dziadek, M.; Bateman, J.; Mascara, T.; Harbers, K.; Gelinas, R.; Jaenisch, R.

1987-01-01

The Mov-13 mouse strain carries a retroviral insertion in the proα1(I) collagen gene that prevents transcription of the gene. Cell lines derived from homozygous embryos do not express type I collagen although normal amounts of proα2 mRNA are synthesized. The authors have introduced genomic clones of either the human or mouse proα1(I) collagen gene into homozygous cell lines to assess whether the human or mouse proα1(I) chains can associate with the endogenous mouse proα2(I) chain to form stable type I collagen. The human gene under control of the simian virus 40 promoter was efficiently transcribed in the transfected cells. Protein analyses revealed that stable heterotrimers consisting of two human α1 chains and one mouse α2 chain were formed and that type I collagen was secreted by the transfected cells at normal rates. However, the electrophoretic migration of both α1(I) and α2(I) chains in the human-mouse hybrid molecules were retarded, compared to the α(I) chains in control mouse cells. Inhibition of the posttranslational hydroxylation of lysine and proline resulted in comigration of human and mouse α1 and α2 chains, suggesting that increased posttranslational modification caused the altered electrophoretic migration in the human-mouse hybrid molecules. Amino acid sequence differences between the mouse and human α chains may interfere with the normal rate of helix formation and increase the degree of posttranslational modifications similar to those observed in patients with lethal perinatal osteogenesis imperfecta. The Mov-13 mouse system should allow the authors to study the effect specific mutations introduced in transfected proα1(I) genes have on the synthesis, assembly, and function of collagen I

Persistence of collagen type II-specific T-cell clones in the synovial membrane of a patient with rheumatoid arthritis

International Nuclear Information System (INIS)

Londei, M.; Savill, C.M.; Verhoef, A.; Brennan, F.; Leech, Z.A.; Feldmann, M.; Duance, V.; Maini, R.N.

1989-01-01

Rheumatoid arthritis is an autoimmune disease characterized by T-cell infiltration of the synovium of joints. Analysis of the phenotype and antigen specificity of the infiltrating cells may thus provide insight into the pathogenesis of rheumatoid arthritis. T cells were cloned with interleukin 2, a procedure that selects for in vivo-activated cells. All clones had the CD4 CDW29 phenotype. Their antigen specificity was tested by using a panel of candidate joint autoantigens. Four of 17 reacted against autologous blood mononuclear cells. Two clones proliferated in response to collagen type II. After 21 months, another set of clones was derived from synovial tissue of the same joint. One of eight clones tested showed a strong proliferative response against collagen type II. The uncloned synovial T cells of a third operation from another joint also responded to collagen type II. The persistence of collagen type II-specific T cells in active rheumatoid joints over a period of 3 years suggests that collagen type II could be one of the autoantigens involved in perpetuating the inflammatory process in rheumatoid arthritis

Osteogenesis imperfecta due to mutations in non-collagenous genes: lessons in the biology of bone formation.

Science.gov (United States)

Marini, Joan C; Reich, Adi; Smith, Simone M

2014-08-01

Osteogenesis imperfecta or 'brittle bone disease' has mainly been considered a bone disorder caused by collagen mutations. Within the last decade, however, a surge of genetic discoveries has created a new paradigm for osteogenesis imperfecta as a collagen-related disorder, where most cases are due to autosomal dominant type I collagen defects, while rare, mostly recessive, forms are due to defects in genes whose protein products interact with collagen protein. This review is both timely and relevant in outlining the genesis, development, and future of this paradigm shift in the understanding of osteogenesis imperfecta. Bone-restricted interferon-induced transmembrane (IFITM)-like protein (BRIL) and pigment epithelium-derived factor (PEDF) defects cause types V and VI osteogenesis imperfecta via defective bone mineralization, while defects in cartilage-associated protein (CRTAP), prolyl 3-hydroxylase 1 (P3H1), and cyclophilin B (CYPB) cause types VII-IX osteogenesis imperfecta via defective collagen post-translational modification. Heat shock protein 47 (HSP47) and FK506-binding protein-65 (FKBP65) defects cause types X and XI osteogenesis imperfecta via aberrant collagen crosslinking, folding, and chaperoning, while defects in SP7 transcription factor, wingless-type MMTV integration site family member 1 (WNT1), trimeric intracellular cation channel type b (TRIC-B), and old astrocyte specifically induced substance (OASIS) disrupt osteoblast development. Finally, absence of the type I collagen C-propeptidase bone morphogenetic protein 1 (BMP1) causes type XII osteogenesis imperfecta due to altered collagen maturation/processing. Identification of these multiple causative defects has provided crucial information for accurate genetic counseling, inspired a recently proposed functional grouping of osteogenesis imperfecta types by shared mechanism to simplify current nosology, and has prodded investigations into common pathways in osteogenesis imperfecta. Such

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....

Derivation of residual radioactive material guidelines for 13 radionuclides present in Operable Unit IV at Brookhaven National Laboratory, Upton, New York

International Nuclear Information System (INIS)

Faillace, E.; Nimmagadda, M.; Yu, C.

1994-12-01

Residual radioactive material guidelines for 13 radionuclides (americium-241; cobalt-60; cesium-137; europium-152, -154, and -155; plutonium-238, -239, and -240; strontium-90; and uranium-234, -235, and -238) were derived for Operable Unit (OU) IV at Brookhaven National Laboratory. This site has been identified for remedial action under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980, as amended by the Superfund Amendments and Reauthorization Act of 1986. Single-nuclide guidelines were derived on the basis of the requirement that the 50-year committed effective dose equivalent to a hypothetical individual who lives or works in the immediate vicinity of OU IV should not exceed a dose constraint of 30 mrem/yr following remedial action for the current use and plausible future use scenarios or a dose limit of 100 mrem/yr for plausible but less likely future use scenarios. The US Department of Energy (DOE) residual radioactive material guideline computer code, RESRAD, was used in this evaluation; RESRAD implements the methodology described in the DOE manual for determining residual radioactive material guidelines. Four potential scenarios were considered; each assumed that, for a period of 1,000 years following remedial action, the site would be used without radiological restrictions. The four scenarios varied with regard to the type of site use, time spent at the site, and sources of food consumed

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

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...

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...

The synthesis and coupling of photoreactive collagen-based peptides to restore integrin reactivity to an inert substrate, chemically-crosslinked collagen

Science.gov (United States)

Malcor, Jean-Daniel; Bax, Daniel; Hamaia, Samir W.; Davidenko, Natalia; Best, Serena M.; Cameron, Ruth E.; Farndale, Richard W.; Bihan, Dominique

2016-01-01

Collagen is frequently advocated as a scaffold for use in regenerative medicine. Increasing the mechanical stability of a collagen scaffold is widely achieved by cross-linking using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxysuccinimide (NHS). However, this treatment consumes the carboxylate-containing amino acid sidechains that are crucial for recognition by the cell-surface integrins, abolishing cell adhesion. Here, we restore cell reactivity to a cross-linked type I collagen film by covalently linking synthetic triple-helical peptides (THPs), mimicking the structure of collagen. These THPs are ligands containing an active cell-recognition motif, GFOGER, a high-affinity binding site for the collagen-binding integrins. We end-stapled peptide strands containing GFOGER by coupling a short diglutamate-containing peptide to their N-terminus, improving the thermal stability of the resulting THP. A photoreactive Diazirine group was grafted onto the end-stapled THP to allow covalent linkage to the collagen film upon UV activation. Such GFOGER-derivatized collagen films showed restored affinity for the ligand-binding I domain of integrin α2β1, and increased integrin-dependent cell attachment and spreading of HT1080 and Rugli cell lines, expressing integrins α2β1 and α1β1, respectively. The method we describe has wide application, beyond collagen films or scaffolds, since the photoreactive diazirine will react with many organic carbon skeletons. PMID:26854392

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.

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...

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

 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.

PPAR-δ Agonist With Mesenchymal Stem Cells Induces Type II Collagen-Producing Chondrocytes in Human Arthritic Synovial Fluid.

Science.gov (United States)

Heck, Bruce E; Park, Joshua J; Makani, Vishruti; Kim, Eun-Cheol; Kim, Dong Hyun

2017-08-01

Osteoarthritis (OA) is an inflammatory joint disease characterized by degeneration of articular cartilage within synovial joints. An estimated 27 million Americans suffer from OA, and the population is expected to reach 67 million in the United States by 2030. Thus, it is urgent to find an effective treatment for OA. Traditional OA treatments have no disease-modifying effect, while regenerative OA therapies such as autologous chondrocyte implantation show some promise. Nonetheless, current regenerative therapies do not overcome synovial inflammation that suppresses the differentiation of mesenchymal stem cells (MSCs) to chondrocytes and the expression of type II collagen, the major constituent of functional cartilage. We discovered a synergistic combination that overcame synovial inflammation to form type II collagen-producing chondrocytes. The combination consists of peroxisome proliferator-activated receptor (PPAR) δ agonist, human bone marrow (hBM)-derived MSCs, and hyaluronic acid (HA) gel. Interestingly, those individual components showed their own strong enhancing effects on chondrogenesis. GW0742, a PPAR-δ agonist, greatly enhanced MSC chondrogenesis and the expression of type II collagen and glycosaminoglycan (GAG) in hBM-MSC-derived chondrocytes. GW0742 also increased the expression of transforming growth factor β that enhances chondrogenesis and suppresses cartilage fibrillation, ossification, and inflammation. HA gel also increased MSC chondrogenesis and GAG production. However, neither GW0742 nor HA gel could enhance the formation of type II collagen-producing chondrocytes from hBM-MSCs within human OA synovial fluid. Our data demonstrated that the combination of hBM-MSCs, PPAR-δ agonist, and HA gel significantly enhanced the formation of type II collagen-producing chondrocytes within OA synovial fluid from 3 different donors. In other words, the novel combination of PPAR-δ agonist, hBM-MSCs, and HA gel can overcome synovial inflammation to form

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

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

Directory of Open Access Journals (Sweden)

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.

Antibacterial and antibiofilm screening of new platinum(IV complexes with some s-alkyl derivatives of thiosalicylic acid

Directory of Open Access Journals (Sweden)

Radojević Ivana

2017-01-01

Full Text Available The influence of 5 new Platinum(IV (Pt(IV complexes with S-alkyl derivatives of thiosalicylic acid (C1-benzyl, C2-methyl, C3-ethyl, C4-propyl and C5- butyl was studied on 16 strains of bacteria. Antibacterial activity was tested using microdilution method with resazurin while antibiofilm activity was observed by tissue culture plate method, using doxycycline as a positive control. The results were expressed as minimum inhibitory concentration (MIC, minimum bactericidal concentration (MBC and biofilm inhibitory concentration (BIC. The best result on Gram positive bacteria exhibited C1 and MIC was <7.81μg/ml against Staphylococcus aureus ATCC 25923. Bifidobacterium animalis subsp. lactis (probiotic was sensitive to C2 (MIC at 15.625 μg/ml. The highest sensitivity of Gram negative bacteria was observed in Escherichia coli ATCC 25922 treated with C1, C2, C3 and C4, in Proteus mirabilis ATCC 12453 treated with C1, and in Pseudomonas aeruginosa treated with C2, C3 and C5 (all MICs at 250 μg/ml. The C2 complex were more efficient as antibiofilm agents and the best results were obtained with C2 acting against S. aureus and S. aureus ATCC 25923 biofilms. In conclusion, we noticed that the tested compounds exhibited promising properties as antibacterial and antibiofilm agents.

Study of hafnium (IV) oxide nanoparticles synthesized by polymerized complex and polymer precursor derived sol-gel methods

KAUST Repository

Ramos-Gonzá lez, R.; Garcí a-Cerda, L. A.; Alshareef, Husam N.; Gnade, Bruce E.; Quevedo-Ló pez, Manuel Angel Quevedo

2010-01-01

This work reports the preparation and characterization of hafnium (IV) oxide (HfO2) nanoparticles grown by derived sol-gel routes that involves the formation of an organic polymeric network. A comparison between polymerized complex (PC) and polymer precursor (PP) methods is presented. For the PC method, citric acid (CA) and ethylene glycol (EG) are used as the chelating and polymerizable reagents, respectively. In the case of PP method, poly(acrylic acid) (PAA) is used as the chelating reagent. In both cases, different precursor gels were prepared and the hafnium (IV) chloride (HfCl4) molar ratio was varied from 0.1 to 1.0 for the PC method and from 0.05 to 0.5 for the PP method. In order to obtain the nanoparticles, the precursors were heat treated at 500 and 800 °C. The thermal characterization of the precursor gels was carried out by thermogravimetric analysis (TGA) and the structural and morphological characterization by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The XRD patterns of the samples obtained by both methods shows the formation of HfO2 at 500 °C with monoclinic crystalline phase. The PC method exhibited also the cubic phase. Finally, the HfO2 nanoparticles size (4 to 11 nm) was determined by TEM and XRD patterns. © (2010) Trans Tech Publications.

Study of hafnium (IV) oxide nanoparticles synthesized by polymerized complex and polymer precursor derived sol-gel methods

KAUST Repository

Ramos-González, R.

2010-03-01

This work reports the preparation and characterization of hafnium (IV) oxide (HfO2) nanoparticles grown by derived sol-gel routes that involves the formation of an organic polymeric network. A comparison between polymerized complex (PC) and polymer precursor (PP) methods is presented. For the PC method, citric acid (CA) and ethylene glycol (EG) are used as the chelating and polymerizable reagents, respectively. In the case of PP method, poly(acrylic acid) (PAA) is used as the chelating reagent. In both cases, different precursor gels were prepared and the hafnium (IV) chloride (HfCl4) molar ratio was varied from 0.1 to 1.0 for the PC method and from 0.05 to 0.5 for the PP method. In order to obtain the nanoparticles, the precursors were heat treated at 500 and 800 °C. The thermal characterization of the precursor gels was carried out by thermogravimetric analysis (TGA) and the structural and morphological characterization by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The XRD patterns of the samples obtained by both methods shows the formation of HfO2 at 500 °C with monoclinic crystalline phase. The PC method exhibited also the cubic phase. Finally, the HfO2 nanoparticles size (4 to 11 nm) was determined by TEM and XRD patterns. © (2010) Trans Tech Publications.

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)

Loss of Col3a1, the gene for Ehlers-Danlos syndrome type IV, results in neocortical dyslamination.

Directory of Open Access Journals (Sweden)

Sung-Jin Jeong

Full Text Available It has recently been discovered that Collagen III, the encoded protein of the type IV Ehlers-Danlos Syndrome (EDS gene, is one of the major constituents of the pial basement membrane (BM and serves as the ligand for GPR56. Mutations in GPR56 cause a severe human brain malformation called bilateral frontoparietal polymicrogyria, in which neurons transmigrate through the BM causing severe mental retardation and frequent seizures. To further characterize the brain phenotype of Col3a1 knockout mice, we performed a detailed histological analysis. We observed a cobblestone-like cortical malformation, with BM breakdown and marginal zone heterotopias in Col3a1⁻/⁻ mouse brains. Surprisingly, the pial BM appeared intact at early stages of development but starting as early as embryonic day (E 11.5, prominent BM defects were observed and accompanied by neuronal overmigration. Although collagen III is expressed in meningeal fibroblasts (MFs, Col3a1⁻/⁻ MFs present no obvious defects. Furthermore, the expression and posttranslational modification of α-dystroglycan was undisturbed in Col3a1⁻/⁻ mice. Based on the previous finding that mutations in COL3A1 cause type IV EDS, our study indicates a possible common pathological pathway linking connective tissue diseases and brain malformations.

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.

Abnormal type I collagen post-translational modification and crosslinking in a cyclophilin B KO mouse model of recessive osteogenesis imperfecta.

Science.gov (United States)

Cabral, Wayne A; Perdivara, Irina; Weis, MaryAnn; Terajima, Masahiko; Blissett, Angela R; Chang, Weizhong; Perosky, Joseph E; Makareeva, Elena N; Mertz, Edward L; Leikin, Sergey; Tomer, Kenneth B; Kozloff, Kenneth M; Eyre, David R; Yamauchi, Mitsuo; Marini, Joan C

2014-06-01

Cyclophilin B (CyPB), encoded by PPIB, is an ER-resident peptidyl-prolyl cis-trans isomerase (PPIase) that functions independently and as a component of the collagen prolyl 3-hydroxylation complex. CyPB is proposed to be the major PPIase catalyzing the rate-limiting step in collagen folding. Mutations in PPIB cause recessively inherited osteogenesis imperfecta type IX, a moderately severe to lethal bone dysplasia. To investigate the role of CyPB in collagen folding and post-translational modifications, we generated Ppib-/- mice that recapitulate the OI phenotype. Knock-out (KO) mice are small, with reduced femoral areal bone mineral density (aBMD), bone volume per total volume (BV/TV) and mechanical properties, as well as increased femoral brittleness. Ppib transcripts are absent in skin, fibroblasts, femora and calvarial osteoblasts, and CyPB is absent from KO osteoblasts and fibroblasts on western blots. Only residual (2-11%) collagen prolyl 3-hydroxylation is detectable in KO cells and tissues. Collagen folds more slowly in the absence of CyPB, supporting its rate-limiting role in folding. However, treatment of KO cells with cyclosporine A causes further delay in folding, indicating the potential existence of another collagen PPIase. We confirmed and extended the reported role of CyPB in supporting collagen lysyl hydroxylase (LH1) activity. Ppib-/- fibroblast and osteoblast collagen has normal total lysyl hydroxylation, while increased collagen diglycosylation is observed. Liquid chromatography/mass spectrometry (LC/MS) analysis of bone and osteoblast type I collagen revealed site-specific alterations of helical lysine hydroxylation, in particular, significantly reduced hydroxylation of helical crosslinking residue K87. Consequently, underhydroxylated forms of di- and trivalent crosslinks are strikingly increased in KO bone, leading to increased total crosslinks and decreased helical hydroxylysine- to lysine-derived crosslink ratios. The altered crosslink

Sphingosine 1-phosphate (S1P) suppresses the collagen-induced activation of human platelets via S1P4 receptor.

Science.gov (United States)

Onuma, Takashi; Tanabe, Kumiko; Kito, Yuko; Tsujimoto, Masanori; Uematsu, Kodai; Enomoto, Yukiko; Matsushima-Nishiwaki, Rie; Doi, Tomoaki; Nagase, Kiyoshi; Akamatsu, Shigeru; Tokuda, Haruhiko; Ogura, Shinji; Iwama, Toru; Kozawa, Osamu; Iida, Hiroki

2017-08-01

Sphingosine 1-phosphate (S1P) is as an extracellular factor that acts as a potent lipid mediator by binding to specific receptors, S1P receptors (S1PRs). However, the precise role of S1P in human platelets that express S1PRs has not yet been fully clarified. We previously reported that heat shock protein 27 (HSP27) is released from human platelets accompanied by its phosphorylation stimulated by collagen. In the present study, we investigated the effect of S1P on the collagen-induced platelet activation. S1P pretreatment markedly attenuated the collagen-induced aggregation. Co-stimulation with S1P and collagen suppressed collagen-induced platelet activation, but the effect was weaker than that of S1P-pretreatment. The collagen-stimulated secretion of platelet-derived growth factor (PDGF)-AB and the soluble CD40 ligand (sCD40L) release were significantly reduced by S1P. In addition, S1P suppressed the collagen-induced release of HSP27 as well as the phosphorylation of HSP27. S1P significantly suppressed the collagen-induced phosphorylation of p38 mitogen-activated protein kinase. S1P increased the levels of GTP-bound Gαi and GTP-bound Gα13 coupled to S1PPR1 and/or S1PR4. CYM50260, a selective S1PR4 agonist, but not SEW2871, a selective S1PR1 agonist, suppressed the collagen-stimulated platelet aggregation, PDGF-AB secretion and sCD40L release. In addition, CYM50260 reduced the release of phosphorylated-HSP27 by collagen as well as the phosphorylation of HSP27. The selective S1PR4 antagonist CYM50358, which failed to affect collagen-induced HSP27 phosphorylation, reversed the S1P-induced attenuation of HSP27 phosphorylation by collagen. These results strongly suggest that S1P inhibits the collagen-induced human platelet activation through S1PR4 but not S1PR1. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

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

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.

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.

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.

Effects of increased collagen-matrix density on the mechanical properties and in vivo absorbability of hydroxyapatite-collagen composites as artificial bone materials

Energy Technology Data Exchange (ETDEWEB)

Yunoki, Shunji [Life Science Group, Tokyo Metropolitan Industrial Technology Research Institute, 2-11-1 Fukasawa, Setagaya-ku, Tokyo 158-0081 (Japan); Sugiura, Hiroaki; Kondo, Eiji; Yasuda, Kazunori [Department of Sports Medicine and Joint Surgery, Graduate School of Medicine, Hokkaido University, Kita-15 Nishi-7, Sapporo, Hokkaido 060-8638 Japan (Japan); Ikoma, Toshiyuki; Tanaka, Junzo, E-mail: yunoki.shunji@iri-tokyo.jp [Department of Metallurgy and Ceramics Science, 2-12-1-S7-1, Ookayama, Meguro-ku, Tokyo 152-8550 (Japan)

2011-02-15

The aim of this study was to evaluate the effects of increased collagen-matrix density on the mechanical properties and in vivo absorbability of porous hydroxyapatite (HAp)-collagen composites as artificial bone materials. Seven types of porous HAp-collagen composites were prepared from HAp nanocrystals and dense collagen fibrils. Their densities and HAp/collagen weight ratios ranged from 122 to 331 mg cm{sup -3} and from 20/80 to 80/20, respectively. The flexural modulus and strength increased with an increase in density, reaching 2.46 {+-} 0.48 and 0.651 {+-} 0.103 MPa, respectively. The porous composites with a higher collagen-matrix density exhibited much higher mechanical properties at the same densities, suggesting that increasing the collagen-matrix density is an effective way of improving the mechanical properties. It was also suggested that other structural factors in addition to collagen-matrix density are required to achieve bone-like mechanical properties. The in vivo absorbability of the composites was investigated in bone defects of rabbit femurs, demonstrating that the absorption rate decreased with increases in the composite density. An exhaustive increase in density is probably limited by decreases in absorbability as artificial bones.

Effects of increased collagen-matrix density on the mechanical properties and in vivo absorbability of hydroxyapatite-collagen composites as artificial bone materials

International Nuclear Information System (INIS)

Yunoki, Shunji; Sugiura, Hiroaki; Kondo, Eiji; Yasuda, Kazunori; Ikoma, Toshiyuki; Tanaka, Junzo

2011-01-01

The aim of this study was to evaluate the effects of increased collagen-matrix density on the mechanical properties and in vivo absorbability of porous hydroxyapatite (HAp)-collagen composites as artificial bone materials. Seven types of porous HAp-collagen composites were prepared from HAp nanocrystals and dense collagen fibrils. Their densities and HAp/collagen weight ratios ranged from 122 to 331 mg cm -3 and from 20/80 to 80/20, respectively. The flexural modulus and strength increased with an increase in density, reaching 2.46 ± 0.48 and 0.651 ± 0.103 MPa, respectively. The porous composites with a higher collagen-matrix density exhibited much higher mechanical properties at the same densities, suggesting that increasing the collagen-matrix density is an effective way of improving the mechanical properties. It was also suggested that other structural factors in addition to collagen-matrix density are required to achieve bone-like mechanical properties. The in vivo absorbability of the composites was investigated in bone defects of rabbit femurs, demonstrating that the absorption rate decreased with increases in the composite density. An exhaustive increase in density is probably limited by decreases in absorbability as artificial bones.

Predicting DPP-IV inhibitors with machine learning approaches

Science.gov (United States)

Cai, Jie; Li, Chanjuan; Liu, Zhihong; Du, Jiewen; Ye, Jiming; Gu, Qiong; Xu, Jun

2017-04-01

Dipeptidyl peptidase IV (DPP-IV) is a promising Type 2 diabetes mellitus (T2DM) drug target. DPP-IV inhibitors prolong the action of glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide (GIP), improve glucose homeostasis without weight gain, edema, and hypoglycemia. However, the marketed DPP-IV inhibitors have adverse effects such as nasopharyngitis, headache, nausea, hypersensitivity, skin reactions and pancreatitis. Therefore, it is still expected for novel DPP-IV inhibitors with minimal adverse effects. The scaffolds of existing DPP-IV inhibitors are structurally diversified. This makes it difficult to build virtual screening models based upon the known DPP-IV inhibitor libraries using conventional QSAR approaches. In this paper, we report a new strategy to predict DPP-IV inhibitors with machine learning approaches involving naïve Bayesian (NB) and recursive partitioning (RP) methods. We built 247 machine learning models based on 1307 known DPP-IV inhibitors with optimized molecular properties and topological fingerprints as descriptors. The overall predictive accuracies of the optimized models were greater than 80%. An external test set, composed of 65 recently reported compounds, was employed to validate the optimized models. The results demonstrated that both NB and RP models have a good predictive ability based on different combinations of descriptors. Twenty "good" and twenty "bad" structural fragments for DPP-IV inhibitors can also be derived from these models for inspiring the new DPP-IV inhibitor scaffold design.

Collagen Type I as a Ligand for Receptor-Mediated Signaling

Directory of Open Access Journals (Sweden)

Iris Boraschi-Diaz

2017-05-01

Full Text Available Collagens form the fibrous component of the extracellular matrix in all multi-cellular animals. Collagen type I is the most abundant collagen present in skin, tendons, vasculature, as well as the organic portion of the calcified tissue of bone and teeth. This review focuses on numerous receptors for which collagen acts as a ligand, including integrins, discoidin domain receptors DDR1 and 2, OSCAR, GPVI, G6b-B, and LAIR-1 of the leukocyte receptor complex (LRC and mannose family receptor uPARAP/Endo180. We explore the process of collagen production and self-assembly, as well as its degradation by collagenases and gelatinases in order to predict potential temporal and spatial sites of action of different collagen receptors. While the interactions of the mature collagen matrix with integrins and DDR are well-appreciated, potential signals from immature matrix as well as collagen degradation products are possible but not yet described. The role of multiple collagen receptors in physiological processes and their contribution to pathophysiology of diseases affecting collagen homeostasis require further studies.

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.

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.

Alleviation of collagen-induced arthritis by the benzoxathiole derivative BOT-4-one in mice: Implication of the Th1- and Th17-cell-mediated immune responses.

Science.gov (United States)

Kim, Byung-Hak; Yoon, Bo Ruem; Kim, Eun Kyoung; Noh, Kum Hee; Kwon, Sun-Ho; Yi, Eun Hee; Lee, Hyun Gyu; Choi, Jung Sook; Kang, Seong Wook; Park, In-Chul; Lee, Won-Woo; Ye, Sang-Kyu

2016-06-15

Autoimmune rheumatoid arthritis is characterized by chronic inflammation and hyperplasia in the synovial joints. Although the cause of rheumatoid arthritis is largely unknown, substantial evidence has supported the importance of immune cells and inflammatory cytokines in the initiation and progression of this disease. Herein, we demonstrated that the benzoxathiole derivative 2-cyclohexylimino-6-methyl-6,7-dihydro-5H-benzo[1,3]oxathiol-4-one (BOT-4-one) alleviated type II collagen-induced arthritis in a mouse model. The levels of pro-inflammatory cytokines are elevated in both human patients with rheumatoid arthritis and mice with collagen-induced arthritis. BOT-4-one treatment reduced the levels of pro-inflammatory cytokines in mice and endotoxin-stimulated macrophages. BOT-4-one treatment suppressed the polarization of Th1- and Th17-cell subsets by inhibiting the expression and production of their lineage-specific master transcription factors and cytokines, as well as activation of signal transducer and activator of transcription proteins. In addition, BOT-4-one inhibited mitogen-activated protein kinase and NF-kappaB signaling as well as the transcriptional activities and DNA-binding of transcription factors, including activator protein-1, cAMP response element-binding protein and NF-kappaB. Our results suggest that BOT-4-one may have therapeutic potential for the treatment of chronic inflammation associated with autoimmune rheumatoid arthritis. Copyright © 2016 Elsevier Inc. All rights reserved.

Lack of collagen XVIII/endostatin exacerbates immune-mediated glomerulonephritis.

Science.gov (United States)

Hamano, Yuki; Okude, Takashi; Shirai, Ryota; Sato, Ikumi; Kimura, Ryota; Ogawa, Makoto; Ueda, Yoshihiko; Yokosuka, Osamu; Kalluri, Raghu; Ueda, Shiro

2010-09-01

Collagen XVIII is a component of the highly specialized extracellular matrix associated with basement membranes of epithelia and endothelia. In the normal kidney, collagen XVIII is distributed throughout glomerular and tubular basement membranes, mesangial matrix, and Bowman's capsule. Proteolytic cleavage within its C-terminal domain releases the fragment endostatin, which has antiangiogenic properties. Because damage to the glomerular basement membrane (GBM) accompanies immune-mediated renal injury, we investigated the role of collagen XVIII/endostatin in this disorder. We induced anti-GBM glomerulonephritis in collagen XVIII alpha1-null and wild-type mice and compared the resulting matrix accumulation, inflammation, and capillary rarefaction. Anti-GBM disease upregulated collagen XVIII/endostatin expression within the GBM and Bowman's capsule of wild-type mice. Collagen XVIII/endostatin-deficient mice developed more severe glomerular and tubulointerstitial injury than wild-type mice. Collagen XVIII/endostatin deficiency altered matrix remodeling, enhanced the inflammatory response, and promoted capillary rarefaction and vascular endothelial cell damage, but did not affect endothelial proliferation. Supplementing collagen XVIII-deficient mice with exogenous endostatin did not affect the progression of anti-GBM disease. Taken together, these results suggest that collagen XVIII/endostatin preserves the integrity of the extracellular matrix and capillaries in the kidney, protecting against progressive glomerulonephritis.

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.

Measurement of Ce(IV) Concentration in Foam Decontaminant containing Fluorosurfactant

Energy Technology Data Exchange (ETDEWEB)

Jung, Chong Hun; Yang, H. B.; Yoon, I. H.; Choi, W. K.; Moon, J. K. [KAERI, Daejeon (Korea, Republic of); Lee, J. S. [Gachon University, Seongnam (Korea, Republic of)

2016-05-15

To improve the stability of the foam, surfactants and inorganic materials such as nanoparticles can be added. A nanoparticle-based foam decontaminant is composed of a surfactant and nanoparticles for the generation and maintenance of foam, and a chemical decontamination agent made of Ce(IV) dissolved in nitric acid. Ce(IV) will be reduced to Ce(III) through the decontamination process. Oxidizing the cerium (III) can be reused as a decontamination agent, Ce(IV). Oxidation treatment technology by ozone uses its strong oxidizing power. It can be regarded as an environmentally friendly process, because ozone cannot be stored and transported like other industrial gases (because it quickly decays into diatomic oxygen) and must therefore be produced on site, and used ozone can be decomposed immediately. A concentration analysis of Ce(IV) in foam decontaminant containing a surfactant is necessary prior to the derivation of optimal conditions for the regeneration of Ce(III) through ozonation treatment. A UV spectrometric method using the absorbance or potentiometric method with a potential difference in Ce(III)/Ce(IV), or a potentiometric titration method using Fe (II), can be used for a Ce(IV) concentration analysis. A UV spectrometric method has a problem receiving the influence of the surfactant, and a potentiometric method is difficult to use because of the problem of an insignificant change in the potential difference value of the Ce(III)/Ce(IV). Thus, the present study was undertaken to determine whether the potentiometric titration method can be used for an analysis of the Ce(IV) concentration in the nanoparticle-based foam decontaminant containing surfactant. It will be effectively used for the Ce(IV) concentration measurement, in relation to the subsequent research on the derivation of optimal conditions for the regeneration of Ce(III) through ozonation treatment.

ECM microenvironment unlocks brown adipogenic potential of adult human bone marrow-derived MSCs.

Science.gov (United States)

Lee, Michelle H; Goralczyk, Anna G; Kriszt, Rókus; Ang, Xiu Min; Badowski, Cedric; Li, Ying; Summers, Scott A; Toh, Sue-Anne; Yassin, M Shabeer; Shabbir, Asim; Sheppard, Allan; Raghunath, Michael

2016-02-17

Key to realizing the diagnostic and therapeutic potential of human brown/brite adipocytes is the identification of a renewable, easily accessible and safe tissue source of progenitor cells, and an efficacious in vitro differentiation protocol. We show that macromolecular crowding (MMC) facilitates brown adipocyte differentiation in adult human bone marrow mesenchymal stem cells (bmMSCs), as evidenced by substantially upregulating uncoupling protein 1 (UCP1) and uncoupled respiration. Moreover, MMC also induced 'browning' in bmMSC-derived white adipocytes. Mechanistically, MMC creates a 3D extracellular matrix architecture enshrouding maturing adipocytes in a collagen IV cocoon that is engaged by paxillin-positive focal adhesions also at the apical side of cells, without contact to the stiff support structure. This leads to an enhanced matrix-cell signaling, reflected by increased phosphorylation of ATF2, a key transcription factor in UCP1 regulation. Thus, tuning the dimensionality of the microenvironment in vitro can unlock a strong brown potential dormant in bone marrow.

Identification and phenotypic characterization of a second collagen adhesin, Scm, and genome-based identification and analysis of 13 other predicted MSCRAMMs, including four distinct pilus loci, in Enterococcus faecium.

Science.gov (United States)

Sillanpää, Jouko; Nallapareddy, Sreedhar R; Prakash, Vittal P; Qin, Xiang; Höök, Magnus; Weinstock, George M; Murray, Barbara E

2008-10-01

Attention has recently been drawn to Enterococcus faecium because of an increasing number of nosocomial infections caused by this species and its resistance to multiple antibacterial agents. However, relatively little is known about the pathogenic determinants of this organism. We have previously identified a cell-wall-anchored collagen adhesin, Acm, produced by some isolates of E. faecium, and a secreted antigen, SagA, exhibiting broad-spectrum binding to extracellular matrix proteins. Here, we analysed the draft genome of strain TX0016 for potential microbial surface components recognizing adhesive matrix molecules (MSCRAMMs). Genome-based bioinformatics identified 22 predicted cell-wall-anchored E. faecium surface proteins (Fms), of which 15 (including Acm) had characteristics typical of MSCRAMMs, including predicted folding into a modular architecture with multiple immunoglobulin-like domains. Functional characterization of one [Fms10; redesignated second collagen adhesin of E. faecium (Scm)] revealed that recombinant Scm(65) (A- and B-domains) and Scm(36) (A-domain) bound to collagen type V efficiently in a concentration-dependent manner, bound considerably less to collagen type I and fibrinogen, and differed from Acm in their binding specificities to collagen types IV and V. Results from far-UV circular dichroism measurements of recombinant Scm(36) and of Acm(37) indicated that these proteins were rich in beta-sheets, supporting our folding predictions. Whole-cell ELISA and FACS analyses unambiguously demonstrated surface expression of Scm in most E. faecium isolates. Strikingly, 11 of the 15 predicted MSCRAMMs clustered in four loci, each with a class C sortase gene; nine of these showed similarity to Enterococcus faecalis Ebp pilus subunits and also contained motifs essential for pilus assembly. Antibodies against one of the predicted major pilus proteins, Fms9 (redesignated EbpC(fm)), detected a 'ladder' pattern of high-molecular-mass protein bands in a

Kaempferol suppresses collagen-induced platelet activation by inhibiting NADPH oxidase and protecting SHP-2 from oxidative inactivation.

Science.gov (United States)

Wang, Su Bin; Jang, Ji Yong; Chae, Yun Hee; Min, Ji Hyun; Baek, Jin Young; Kim, Myunghee; Park, Yunjeong; Hwang, Gwi Seo; Ryu, Jae-Sang; Chang, Tong-Shin

2015-06-01

Reactive oxygen species (ROS) generated upon collagen stimulation act as second messengers to propagate various platelet-activating events. Among the ROS-generating enzymes, NADPH oxidase (NOX) plays a prominent role in platelet activation. Thus, NOX has been suggested as a novel target for anti-platelet drug development. Although kaempferol has been identified as a NOX inhibitor, the influence of kaempferol on the activation of platelets and the underlying mechanism have never been investigated. Here, we studied the effects of kaempferol on NOX activation, ROS-dependent signaling pathways, and functional responses in collagen-stimulated platelets. Superoxide anion generation stimulated by collagen was significantly inhibited by kaempferol in a concentration-dependent manner. More importantly, kaempferol directly bound p47(phox), a major regulatory subunit of NOX, and significantly inhibited collagen-induced phosphorylation of p47(phox) and NOX activation. In accordance with the inhibition of NOX, ROS-dependent inactivation of SH2 domain-containing protein tyrosine phosphatase-2 (SHP-2) was potently protected by kaempferol. Subsequently, the specific tyrosine phosphorylation of key components (Syk, Vav1, Btk, and PLCγ2) of collagen receptor signaling pathways was suppressed by kaempferol. Kaempferol also attenuated downstream responses, including cytosolic calcium elevation, P-selectin surface exposure, and integrin-αIIbβ3 activation. Ultimately, kaempferol inhibited platelet aggregation and adhesion in response to collagen in vitro and prolonged in vivo thrombotic response in carotid arteries of mice. This study shows that kaempferol impairs collagen-induced platelet activation through inhibition of NOX-derived ROS production and subsequent oxidative inactivation of SHP-2. This effect suggests that kaempferol has therapeutic potential for the prevention and treatment of thrombovascular diseases. Copyright © 2015 Elsevier Inc. All rights reserved.

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.

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.

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

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.

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.

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

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...

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....

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.

Modulation of hematopoietic progenitor cell fate in vitro by varying collagen oligomer matrix stiffness in the presence or absence of osteoblasts.

Science.gov (United States)

Chitteti, Brahmananda Reddy; Kacena, Melissa A; Voytik-Harbin, Sherry L; Srour, Edward F

2015-10-01

To recreate the in vivo hematopoietic cell microenvironment or niche and to study the impact of extracellular matrix (ECM) biophysical properties on hematopoietic progenitor cell (HPC) proliferation and function, mouse bone-marrow derived HPC (Lin-Sca1+cKit+/(LSK) were cultured within three-dimensional (3D) type I collagen oligomer matrices. To generate a more physiologic milieu, 3D cultures were established in both the presence and absence of calvariae-derived osteoblasts (OB). Collagen oligomers were polymerized at varying concentration to give rise to matrices of different fibril densities and therefore matrix stiffness (shear storage modulus, 50-800 Pa). Decreased proliferation and increased clonogenicity of LSK cells was associated with increase of matrix stiffness regardless of whether OB were present or absent from the 3D culture system. Also, regardless of whether OB were or were not added to the 3D co-culture system, LSK within 800 Pa collagen oligomer matrices maintained the highest percentage of Lin-Sca1+ cells as well as higher percentage of cells in quiescent state (G0/G1) compared to 50 Pa or 200Pa matrices. Collectively, these data illustrate that biophysical features of collagen oligomer matrices, specifically fibril density-induced modulation of matrix stiffness, provide important guidance cues in terms of LSK expansion and differentiation and therefore maintenance of progenitor cell function. Copyright © 2015. Published by Elsevier B.V.

Neurotrophins differentially stimulate the growth of cochlear neurites on collagen surfaces and in gels☆

Science.gov (United States)

Xie, Joanna; Pak, Kwang; Evans, Amaretta; Kamgar-Parsi, Andy; Fausti, Stephen; Mullen, Lina; Ryan, Allen Frederic

2013-01-01

The electrodes of a cochlear implant are located far from the surviving neurons of the spiral ganglion, which results in decreased precision of neural activation compared to the normal ear. If the neurons could be induced to extend neurites toward the implant, it might be possible to stimulate more discrete subpopulations of neurons, and to increase the resolution of the device. However, a major barrier to neurite growth toward a cochlear implant is the fluid filling the scala tympani, which separates the neurons from the electrodes. The goal of this study was to evaluate the growth of cochlear neurites in three-dimensional extracellular matrix molecule gels, and to increase biocompatibility by using fibroblasts stably transfected to produce neurotrophin-3 and brain-derived neurotrophic factor. Spiral ganglion explants from neonatal rats were evaluated in cultures. They were exposed to soluble neurotrophins, cells transfected to secrete neurotrophins, and/or collagen gels. We found that cochlear neurites grew readily on collagen surfaces and in three-dimensional collagen gels. Co-culture with cells producing neurotrophin-3 resulted in increased numbers of neurites, and neurites that were longer than when explants were cultured with control fibroblasts stably transfected with green fluorescent protein. Brain-derived neurotrophic factor-producing cells resulted in a more dramatic increase in the number of neurites, but there was no significant effect on neurite length. It is suggested that extracellular matrix molecule gels and cells transfected to produce neurotrophins offer an opportunity to attract spiral ganglion neurites toward a cochlear implant. PMID:24459465

Absence of FKBP10 in recessive type XI osteogenesis imperfecta leads to diminished collagen cross-linking and reduced collagen deposition in extracellular matrix.

Science.gov (United States)

Barnes, Aileen M; Cabral, Wayne A; Weis, MaryAnn; Makareeva, Elena; Mertz, Edward L; Leikin, Sergey; Eyre, David; Trujillo, Carlos; Marini, Joan C

2012-11-01

Recessive osteogenesis imperfecta (OI) is caused by defects in genes whose products interact with type I collagen for modification and/or folding. We identified a Palestinian pedigree with moderate and lethal forms of recessive OI caused by mutations in FKBP10 or PPIB, which encode endoplasmic reticulum resident chaperone/isomerases FKBP65 and CyPB, respectively. In one pedigree branch, both parents carry a deletion in PPIB (c.563_566delACAG), causing lethal type IX OI in their two children. In another branch, a child with moderate type XI OI has a homozygous FKBP10 mutation (c.1271_1272delCCinsA). Proband FKBP10 transcripts are 4% of control and FKBP65 protein is absent from proband cells. Proband collagen electrophoresis reveals slight band broadening, compatible with ≈10% over-modification. Normal chain incorporation, helix folding, and collagen T(m) support a minimal general collagen chaperone role for FKBP65. However, there is a dramatic decrease in collagen deposited in culture despite normal collagen secretion. Mass spectrometry reveals absence of hydroxylation of the collagen telopeptide lysine involved in cross-linking, suggesting that FKBP65 is required for lysyl hydroxylase activity or access to type I collagen telopeptide lysines, perhaps through its function as a peptidylprolyl isomerase. Proband collagen to organics ratio in matrix is approximately 30% of normal in Raman spectra. Immunofluorescence shows sparse, disorganized collagen fibrils in proband matrix. Published 2012 Wiley Periodicals, Inc.*This article is a US Government work and, as such, is in the public domain of the United States of America.

Thrombin induces epithelial-mesenchymal transition and collagen production by retinal pigment epithelial cells via autocrine PDGF-receptor signaling.

Science.gov (United States)

Bastiaans, Jeroen; van Meurs, Jan C; van Holten-Neelen, Conny; Nagtzaam, Nicole M A; van Hagen, P Martin; Chambers, Rachel C; Hooijkaas, Herbert; Dik, Willem A

2013-12-19

De-differentiation of RPE cells into mesenchymal cells (epithelial-mesenchymal transition; EMT) and associated collagen production contributes to development of proliferative vitreoretinopathy (PVR). In patients with PVR, intraocular coagulation cascade activation occurs and may play an important initiating role. Therefore, we examined the effect of the coagulation proteins factor Xa and thrombin on EMT and collagen production by RPE cells. Retinal pigment epithelial cells were stimulated with factor Xa or thrombin and the effect on zonula occludens (ZO)-1, α-smooth muscle actin (α-SMA), collagen, and platelet-derived growth factor (PDGF)-B were determined by real-time quantitative-polymerase chain reaction (RQ-PCR), immunofluorescence microscopy, and HPLC and ELISA for collagen and PDGF-BB in culture supernatants, respectively. PDGF-receptor activation was determined by phosphorylation analysis and inhibition studies using the PDGF-receptor tyrosine kinase inhibitor AG1296. Thrombin reduced ZO-1 gene expression (P production of α-SMA and collagen increased. In contrast to thrombin, factor Xa hardly stimulated EMT by RPE. Thrombin clearly induced PDGF-BB production and PDGF-Rβ chain phosphorylation in RPE. Moreover, AG1296 significantly blocked the effect of thrombin on EMT and collagen production. Our findings demonstrate that thrombin is a potent inducer of EMT by RPE via autocrine activation of PDGF-receptor signaling. Coagulation cascade-induced EMT of RPE may thus contribute to the formation of fibrotic retinal membranes in PVR and should be considered as treatment target in PVR.

A three-dimensional hierarchical collagen scaffold fabricated by a combined solid freeform fabrication (SFF) and electrospinning process to enhance mesenchymal stem cell (MSC) proliferation

International Nuclear Information System (INIS)

Ahn, SeungHyun; Kim, GeunHyung; Koh, Young Ho

2010-01-01

Collagen has the advantage of being very similar to macromolecular substances that can be recognized and metabolized in the biological environment. Although the natural material has superior property for this purpose, its use to fabricate reproducible and pore-structure-controlled 3D structures, which are designed to allow the entry of sufficient cells and the easy diffusion of nutrients, has been limited due to its low processability. Here, we propose a hybrid technology that combines a cryogenic plotting system with an electrospinning process. Using this technique, an easily pore-size-controllable hierarchical 3D scaffold consisting of micro-sized highly porous collagen strands and micro/nano-sized collagen fibers was fabricated. The pore structure of the collagen scaffold was controlled by the collagen micro/nanofibers, which were layered in the scaffold. The hierarchical scaffolds were characterized with respect to initial cell attachment and proliferation of bone marrow-derived mesenchymal stem cells within the scaffolds. The hierarchical scaffold exhibited incredibly enhanced initial cell attachment and cell compactness between pores of the plotted scaffold relative to the normally designed 3D collagen scaffold.

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

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.

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.

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.

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.

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)

Amine and Titanium (IV Chloride, Boron (III Chloride or Zirconium (IV Chloride-Promoted Baylis-Hillman Reactions

Directory of Open Access Journals (Sweden)

Shi-Cong Cui

2001-10-01

Full Text Available The Baylis-Hillman reactions of various aryl aldehydes with methyl vinyl ketone at temperatures below -20oC using Lewis acids such as titanium (IV chloride, boron (III chloride or zirconium (IV chloride in the presence of a catalytic amount of selected amines used as a Lewis bases afford the chlorinated compounds 1 as the major product in very high yields. Acrylonitrile can also undergo the same reaction to give the corresponding chlorinated product in moderate yield. A plausible reaction mechanism is proposed. However, if the reaction was carried out at room temperature (ca. 20oC, then the Z-configuration of the elimination product 3, derived from 1, was formed as the major product.

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...

Abnormal type I collagen post-translational modification and crosslinking in a cyclophilin B KO mouse model of recessive osteogenesis imperfecta.

Directory of Open Access Journals (Sweden)

Wayne A Cabral

2014-06-01

Full Text Available Cyclophilin B (CyPB, encoded by PPIB, is an ER-resident peptidyl-prolyl cis-trans isomerase (PPIase that functions independently and as a component of the collagen prolyl 3-hydroxylation complex. CyPB is proposed to be the major PPIase catalyzing the rate-limiting step in collagen folding. Mutations in PPIB cause recessively inherited osteogenesis imperfecta type IX, a moderately severe to lethal bone dysplasia. To investigate the role of CyPB in collagen folding and post-translational modifications, we generated Ppib-/- mice that recapitulate the OI phenotype. Knock-out (KO mice are small, with reduced femoral areal bone mineral density (aBMD, bone volume per total volume (BV/TV and mechanical properties, as well as increased femoral brittleness. Ppib transcripts are absent in skin, fibroblasts, femora and calvarial osteoblasts, and CyPB is absent from KO osteoblasts and fibroblasts on western blots. Only residual (2-11% collagen prolyl 3-hydroxylation is detectable in KO cells and tissues. Collagen folds more slowly in the absence of CyPB, supporting its rate-limiting role in folding. However, treatment of KO cells with cyclosporine A causes further delay in folding, indicating the potential existence of another collagen PPIase. We confirmed and extended the reported role of CyPB in supporting collagen lysyl hydroxylase (LH1 activity. Ppib-/- fibroblast and osteoblast collagen has normal total lysyl hydroxylation, while increased collagen diglycosylation is observed. Liquid chromatography/mass spectrometry (LC/MS analysis of bone and osteoblast type I collagen revealed site-specific alterations of helical lysine hydroxylation, in particular, significantly reduced hydroxylation of helical crosslinking residue K87. Consequently, underhydroxylated forms of di- and trivalent crosslinks are strikingly increased in KO bone, leading to increased total crosslinks and decreased helical hydroxylysine- to lysine-derived crosslink ratios. The altered

Abnormal Type I Collagen Post-translational Modification and Crosslinking in a Cyclophilin B KO Mouse Model of Recessive Osteogenesis Imperfecta

Science.gov (United States)

Cabral, Wayne A.; Perdivara, Irina; Weis, MaryAnn; Terajima, Masahiko; Blissett, Angela R.; Chang, Weizhong; Perosky, Joseph E.; Makareeva, Elena N.; Mertz, Edward L.; Leikin, Sergey; Tomer, Kenneth B.; Kozloff, Kenneth M.; Eyre, David R.; Yamauchi, Mitsuo; Marini, Joan C.

2014-01-01

Cyclophilin B (CyPB), encoded by PPIB, is an ER-resident peptidyl-prolyl cis-trans isomerase (PPIase) that functions independently and as a component of the collagen prolyl 3-hydroxylation complex. CyPB is proposed to be the major PPIase catalyzing the rate-limiting step in collagen folding. Mutations in PPIB cause recessively inherited osteogenesis imperfecta type IX, a moderately severe to lethal bone dysplasia. To investigate the role of CyPB in collagen folding and post-translational modifications, we generated Ppib−/− mice that recapitulate the OI phenotype. Knock-out (KO) mice are small, with reduced femoral areal bone mineral density (aBMD), bone volume per total volume (BV/TV) and mechanical properties, as well as increased femoral brittleness. Ppib transcripts are absent in skin, fibroblasts, femora and calvarial osteoblasts, and CyPB is absent from KO osteoblasts and fibroblasts on western blots. Only residual (2–11%) collagen prolyl 3-hydroxylation is detectable in KO cells and tissues. Collagen folds more slowly in the absence of CyPB, supporting its rate-limiting role in folding. However, treatment of KO cells with cyclosporine A causes further delay in folding, indicating the potential existence of another collagen PPIase. We confirmed and extended the reported role of CyPB in supporting collagen lysyl hydroxylase (LH1) activity. Ppib−/− fibroblast and osteoblast collagen has normal total lysyl hydroxylation, while increased collagen diglycosylation is observed. Liquid chromatography/mass spectrometry (LC/MS) analysis of bone and osteoblast type I collagen revealed site-specific alterations of helical lysine hydroxylation, in particular, significantly reduced hydroxylation of helical crosslinking residue K87. Consequently, underhydroxylated forms of di- and trivalent crosslinks are strikingly increased in KO bone, leading to increased total crosslinks and decreased helical hydroxylysine- to lysine-derived crosslink ratios. The altered

Enzyme-linked immunosorbent assay (ELISAs) for metalloproteinase derived type II collagen neoepitope, CIIM--increased serum CIIM in subjects with severe radiographic osteoarthritis

DEFF Research Database (Denmark)

Bay-Jensen, Anne-Christine; Liu, Qi; Byrjalsen, Inger

2011-01-01

OBJECTIVES: In joint degenerative diseases, the collagens are degraded by matrix metalloproteinases and protein fragments are released to serum as potential biomarkers. METHODS: A collagen type II specific neoepitope, CIIM, was identified (…RDGAAG(1053)) by mass spectrometry. Two ELISAs against...... the neoepitope were developed. CIIM was measured in cartilage explants in the presence or absence of protease inhibitors. CIIM was measured in OA synovial fluid (n=51) and serum (n=156). Knee OA was graded by standard Kellgren-Lawrence (KL) score. RESULTS: The ELISAs showed good technical performance; CV%,

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.

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.

The response to estrogen deprivation on cartilage collagen degradation markers; CTX-II is unique compared to other markers of collagen turnover

DEFF Research Database (Denmark)

Bay-Jensen, Anne-Christine; Tabassi, Nadine; Sondergaard, Lene

2009-01-01

ABSTRACT: INTRODUCTION: The urinary level of type II collagen degradation marker CTX-II is increased in postmenopausal women and in ovariectomized rats, suggesting that estrogen deprivation induces cartilage breakdown. Here we investigate whether this response to estrogen holds true for other type...... II collagen turnover markers known to be affected in osteoarthritis, and whether it relates to its presence in specific areas of cartilage tissue. METHODS: The type II collagen degradation markers CTX-II and Helix-II were measured in body fluids of pre- and postmenopausal women and of ovariectomized...... rats receiving estrogen or not. Levels of PIIANP, a marker of type II collagen synthesis, were also measured in rats. Rat knee cartilage was analyzed for immunoreactivity of CTX-II and PIIANP and for type II collagen expression. RESULTS: As expected, urinary levels of CTX-II are significantly increased...

Astragaloside IV Prevents Cardiac Remodeling in the Apolipoprotein E-Deficient Mice by Regulating Cardiac Homeostasis and Oxidative Stress

Directory of Open Access Journals (Sweden)

Xiong-Zhi Li

2017-12-01

Full Text Available Background: Hypercholesterolemia is a risk factor for the development of cardiac hypertrophy. Astragaloside IV (AST-IV possesses cardiovascular protective properties. We hypothesize that AST-IV prevents cardiac remodeling with hypercholesterolemia via modulating tissue homeostasis and alleviating oxidative stress. Methods: The ApoE-/- mice were treated with AST-IV at 1 or 10 mg/kg for 8 weeks. The blood lipids tests, echocardiography, and TUNEL were performed. The mRNA expression profile was detected by real-time PCR. The myocytes size and number, and the expressions of proliferation (ki67, senescence (p16INK4a, oxidant (NADPH oxidase 4, NOX4 and antioxidant (superoxide dismutase, SOD were observed by immunofluorescence staining. Results: Neither 1 mg/kg nor 10 mg/kg AST-IV treatment could decrease blood lipids in ApoE-/- mice. However, the decreased left ventricular ejection fraction (LVEF and fractional shortening (FS in ApoE–/– mice were significantly improved after AST-IV treatment. The cardiac collagen volume fraction declined nearly in half after AST-IV treatment. The enlarged myocyte size was suppressed, and myocyte number was recovered, and the alterations of genes expressions linked to cell cycle, proliferation, senescence, p53-apoptosis pathway and oxidant-antioxidants in the hearts of ApoE-/- mice were reversed after AST-IV treatment. The decreased ki67 and increased p16INK4a in the hearts of ApoE-/- mice were recovered after AST-IV treatment. The percentages of apoptotic myocytes and NOX4-positive cells in AST-IV treated mice were decreased, which were consistent with the gene expressions. Conclusion: AST-IV treatment could prevent cardiac remodeling and recover the impaired ventricular function induced by hypercholesterolemia. The beneficial effect of AST-IV might partly be through regulating cardiac homeostasis and anti-oxidative stress.

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

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

Synthesis, Characterization, and Cytotoxicity of the First Oxaliplatin Pt(IV Derivative Having a TSPO Ligand in the Axial Position

Directory of Open Access Journals (Sweden)

Salvatore Savino

2016-06-01

Full Text Available The first Pt(IV derivative of oxaliplatin carrying a ligand for TSPO (the 18-kDa mitochondrial translocator protein has been developed. The expression of the translocator protein in the brain and liver of healthy humans is usually low, oppositely to steroid-synthesizing and rapidly proliferating tissues, where TSPO is much more abundant. The novel Pt(IV complex, cis,trans,cis-[Pt(ethanedioatoCl{2-(2-(4-(6,8-dichloro-3-(2-(dipropylamino-2-oxoethylimidazo[1,2-a]pyridin-2-ylphenoxyacetate-ethanolato}(1R,2R-DACH] (DACH = diaminocyclohexane, has been fully characterized by spectroscopic and spectrometric techniques and tested in vitro against human MCF7 breast carcinoma, U87 glioblastoma, and LoVo colon adenocarcinoma cell lines. In addition, affinity for TSPO (IC50 = 18.64 nM, cellular uptake (ca. 2 times greater than that of oxaliplatin in LoVo cancer cells, after 24 h treatment, and perturbation of cell cycle progression were investigated. Although the new compound was less active than oxaliplatin and did not exploit a synergistic proapoptotic effect due to the presence of the TSPO ligand, it appears to be promising in a receptor-mediated drug targeting context towards TSPO-overexpressing tumors, in particular colorectal cancer (IC50 = 2.31 μM after 72 h treatment.

Mac-2 binding protein is a cell-adhesive protein of the extracellular matrix which self-assembles into ring-like structures and binds beta1 integrins, collagens and fibronectin

DEFF Research Database (Denmark)

Sasaki, T; Brakebusch, C; Engel, J

1998-01-01

Human Mac-2 binding protein (M2BP) was prepared in recombinant form from the culture medium of 293 kidney cells and consisted of a 92 kDa subunit. The protein was obtained in a native state as indicated by CD spectroscopy, demonstrating alpha-helical and beta-type structure, and by protease resis...... in the extracellular matrix of several mouse tissues....... in solid-phase assays to collagens IV, V and VI, fibronectin and nidogen, but not to fibrillar collagens I and III or other basement membrane proteins. The protein also mediated adhesion of cell lines at comparable strength with laminin. Adhesion to M2BP was inhibited by antibodies to integrin beta1...

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.

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.

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.

Exosomes derived from human umbilical cord blood mesenchymal stem cells stimulates rejuvenation of human skin.

Science.gov (United States)

Kim, Yoon-Jin; Yoo, Sae Mi; Park, Hwan Hee; Lim, Hye Jin; Kim, Yu-Lee; Lee, Seunghee; Seo, Kwang-Won; Kang, Kyung-Sun

2017-11-18

Human umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) play an important role in cutaneous wound healing, and recent studies suggested that MSC-derived exosomes activate several signaling pathways, which are conducive in wound healing and cell growth. In this study, we investigated the roles of exosomes that are derived from USC-CM (USC-CM Exos) in cutaneous collagen synthesis and permeation. We found that USC-CM has various growth factors associated with skin rejuvenation. Our in vitro results showed that USC-CM Exos integrate in Human Dermal Fibroblasts (HDFs) and consequently promote cell migration and collagen synthesis of HDFs. Moreover, we evaluated skin permeation of USC-CM Exos by using human skin tissues. Results showed that Exo-Green labeled USC-CM Exos approached the outermost layer of the epidermis after 3 h and gradually approached the epidermis after 18 h. Moreover, increased expressions of Collagen I and Elastin were found after 3 days of treatment on human skin. The results showed that USC-CM Exos is absorbed into human skin, it promotes Collagen I and Elastin synthesis in the skin, which are essential to skin rejuvenation and shows the potential of USC-CM integration with the cosmetics or therapeutics. Copyright © 2017 Elsevier Inc. All rights reserved.

Development of a novel collagen-GAG nanofibrous scaffold via electrospinning

Energy Technology Data Exchange (ETDEWEB)

Zhong Shaoping [Department of Chemical and Biomolecular Engineering, National University of Singapore, 10 Kent Ridge Crescent 119260 (Singapore); Teo, Wee Eong [Division of Bioengineering, National University of Singapore, 10 Kent Ridge Crescent 119260 (Singapore); Zhu Xiao [Singapore Eye Research Institute, Singapore National Eye Center, 11 Third Hospital Avenue, Singapore 168751 (Singapore); Beuerman, Roger [Singapore Eye Research Institute, Singapore National Eye Center, 11 Third Hospital Avenue, Singapore 168751 (Singapore); Ramakrishna, Seeram [Division of Bioengineering, National University of Singapore, 10 Kent Ridge Crescent 119260 (Singapore); Yung, Lin Yue Lanry [Department of Chemical and Biomolecular Engineering, National University of Singapore, 10 Kent Ridge Crescent 119260 (Singapore)]. E-mail: cheyly@nus.edu.sg

2007-03-15

Collagen and glycosaminoglycan (GAG) are native constituents of human tissues and are widely utilized to fabricate scaffolds serving as an analog of native extracellular matrix (ECM).The development of blended collagen and GAG scaffolds may potentially be used in many soft tissue engineering applications since the scaffolds mimic the structure and biological function of native ECM. In this study, we were able to obtain a novel nanofibrous collagen-GAG scaffold by electrospinning with collagen and chondroitin sulfate (CS), a widely used GAG. The electrospun collagen-GAG scaffold exhibited a uniform fiber structure in nano-scale diameter. By crosslinking with glutaraldehyde vapor, the collagen-GAG scaffolds could resist from collagenase degradation and enhance the biostability of the scaffolds. This led to the increased proliferation of rabbit conjunctiva fibroblast on the scaffolds. Incorporation of CS into collagen nanofibers without crosslinking did not increase the biostability but still promoted cell growth. In conclusion, the electrospun collagen-GAG scaffolds, with high surface-to-volume ratio, may potentially provide a better environment for tissue formation/biosynthesis compared with the traditional scaffolds.

Development of a novel collagen-GAG nanofibrous scaffold via electrospinning

International Nuclear Information System (INIS)

Zhong Shaoping; Teo, Wee Eong; Zhu Xiao; Beuerman, Roger; Ramakrishna, Seeram; Yung, Lin Yue Lanry

2007-01-01

Collagen and glycosaminoglycan (GAG) are native constituents of human tissues and are widely utilized to fabricate scaffolds serving as an analog of native extracellular matrix (ECM).The development of blended collagen and GAG scaffolds may potentially be used in many soft tissue engineering applications since the scaffolds mimic the structure and biological function of native ECM. In this study, we were able to obtain a novel nanofibrous collagen-GAG scaffold by electrospinning with collagen and chondroitin sulfate (CS), a widely used GAG. The electrospun collagen-GAG scaffold exhibited a uniform fiber structure in nano-scale diameter. By crosslinking with glutaraldehyde vapor, the collagen-GAG scaffolds could resist from collagenase degradation and enhance the biostability of the scaffolds. This led to the increased proliferation of rabbit conjunctiva fibroblast on the scaffolds. Incorporation of CS into collagen nanofibers without crosslinking did not increase the biostability but still promoted cell growth. In conclusion, the electrospun collagen-GAG scaffolds, with high surface-to-volume ratio, may potentially provide a better environment for tissue formation/biosynthesis compared with the traditional scaffolds

Both TALENs and CRISPR/Cas9 directly target the HBB IVS2-654 (C > T) mutation in β-thalassemia-derived iPSCs.

Science.gov (United States)

Xu, Peng; Tong, Ying; Liu, Xiu-zhen; Wang, Ting-ting; Cheng, Li; Wang, Bo-yu; Lv, Xiang; Huang, Yue; Liu, De-pei

2015-07-09

β-Thalassemia is one of the most common genetic blood diseases and is caused by either point mutations or deletions in the β-globin (HBB) gene. The generation of patient-specific induced pluripotent stem cells (iPSCs) and subsequent correction of the disease-causing mutations may be a potential therapeutic strategy for this disease. Due to the low efficiency of typical homologous recombination, endonucleases, including TALENs and CRISPR/Cas9, have been widely used to enhance the gene correction efficiency in patient-derived iPSCs. Here, we designed TALENs and CRISPR/Cas9 to directly target the intron2 mutation site IVS2-654 in the globin gene. We observed different frequencies of double-strand breaks (DSBs) at IVS2-654 loci using TALENs and CRISPR/Cas9, and TALENs mediated a higher homologous gene targeting efficiency compared to CRISPR/Cas9 when combined with the piggyBac transposon donor. In addition, more obvious off-target events were observed for CRISPR/Cas9 compared to TALENs. Finally, TALENs-corrected iPSC clones were selected for erythroblast differentiation using the OP9 co-culture system and detected relatively higher transcription of HBB than the uncorrected cells. This comparison of using TALENs or CRISPR/Cas9 to correct specific HBB mutations in patient-derived iPSCs will guide future applications of TALENs- or CRISPR/Cas9-based gene therapies in monogenic diseases.

Hepatic imaging in stage IV-S neuroblastoma

International Nuclear Information System (INIS)

Franken, E.A. Jr.; Smith, W.L.; Iowa Univ., Iowa City; Cohen, M.D.; Kisker, C.T.; Platz, C.E.

1986-01-01

Stage IV-S neuroblastoma describes a group of infants with tumor spread limited to liver, skin, or bone marrow. Such patients, who constitute about 25% of affected infants with neuroblastoma, may expect spontaneous tumor remission. We report 18 infants with Stage IV-S neuroblastoma, 83% of whom had liver involvement. Imaging investigations included Technetium 99m sulfur colloid scan, ultrasound, and CT. Two patterns of liver metastasis were noted: ill-defined nodules or diffuse tumor throughout the liver. Distinction of normal and abnormal liver with diffuse type metastasis could be quite difficult, particularly with liver scans. We conclude that patients with Stage IV-S neuroblastoma have ultrasound or CT examination as an initial workup, with nuclear medicine scans reserved for followup studies. (orig.)

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)....

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.

Mycobacterial laminin-binding histone-like protein mediates collagen-dependent cytoadherence

Directory of Open Access Journals (Sweden)

André Alves Dias

2012-12-01

Full Text Available When grown in the presence of exogenous collagen I, Mycobacterium bovis BCG was shown to form clumps. Scanning electron microscopy examination of these clumps revealed the presence of collagen fibres cross-linking the bacilli. Since collagen is a major constituent of the eukaryotic extracellular matrices, we assayed BCG cytoadherence in the presence of exogenous collagen I. Collagen increased the interaction of the bacilli with A549 type II pneumocytes or U937 macrophages, suggesting that BCG is able to recruit collagen to facilitate its attachment to host cells. Using an affinity chromatography approach, we have isolated a BCG collagen-binding protein corresponding to the previously described mycobacterial laminin-binding histone-like protein (LBP/Hlp, a highly conserved protein associated with the mycobacterial cell wall. Moreover, Mycobacterium leprae LBP/Hlp, a well-characterized adhesin, was also able to bind collagen I. Finally, using recombinant fragments of M. leprae LBP/Hlp, we mapped the collagen-binding activity within the C-terminal domain of the adhesin. Since this protein was already shown to be involved in the recognition of laminin and heparan sulphate-containing proteoglycans, the present observations reinforce the adhesive activities of LBP/Hlp, which can be therefore considered as a multifaceted mycobacterial adhesin, playing an important role in both leprosy and tuberculosis pathogenesis.

Maturation of human embryonic stem cell-derived cardiomyocytes (hESC-CMs) in 3D collagen matrix: Effects of niche cell supplementation and mechanical stimulation.

Science.gov (United States)

Zhang, W; Kong, C W; Tong, M H; Chooi, W H; Huang, N; Li, R A; Chan, B P

2017-02-01

Cardiomyocytes derived from human embryonic stem cells (hESC-CMs) are regarded as a promising source for regenerative medicine, drug testing and disease modeling. Nevertheless, cardiomyocytes are immature in terms of their contractile structure, metabolism and electrophysiological properties. Here, we fabricate cardiac muscle strips by encapsulating hESC-CMs in collagen-based biomaterials. Supplementation of niche cells at 3% to the number of hESC-CMs enhance the maturation of the hESC-CMs in 3D tissue matrix. The benefits of adding mesenchymal stem cells (MSCs) are comparable to that of adding fibroblasts. These two cell types demonstrate similar effects in promoting the compaction and cell spreading, as well as expression of maturation markers at both gene and protein levels. Mechanical loading, particularly cyclic stretch, produces engineered cardiac tissues with higher maturity in terms of twitch force, elastic modulus, sarcomere length and molecular signature, when comparing to static stretch or non-stretched controls. The current study demonstrates that the application of niche cells and mechanical stretch both stimulate the maturation of hESC-CMs in 3D architecture. Our results therefore suggest that this 3D model can be used for in vitro cardiac maturation study. Cardiomyocytes derived from human embryonic stem cells (hESC-CMs) are regarded as being a promising source of cells for regenerative medicine, drug testing and disease modeling. Nevertheless, cardiomyocytes are immature in terms of their contractile structure, metabolism and electrophysiological properties. In the current study, we have fabricated cardiac muscle strips by encapsulating hESC-CMs in collagen-based biomaterials and demonstrated that supplementation of mesenchymal niche cells as well as provision of mechanical loading particularly stretching have significantly promoted the maturation of the cardiomyocytes and hence improved the mechanical functional characteristics of the tissue strips

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...

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.

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

Novel synthesis strategy for composite hydrogel of collagen/hydroxyapatite-microsphere originating from conversion of CaCO3 templates.

Science.gov (United States)

Wei, Qingrong; Lu, Jian; Wang, Qiaoying; Fan, Hongsong; Zhang, Xingdong

2015-03-20

Inspired by coralline-derived hydroxyapatite, we designed a methodological route to synthesize carbonated-hydroxyapatite microspheres from the conversion of CaCO3 spherulite templates within a collagen matrix under mild conditions and thus constructed the composite hydrogel of collagen/hydroxyapatite-microspheres. Fourier transform infrared spectroscopy (FTIR) and x-ray diffraction (XRD) were employed to confirm the successful generation of the carbonated hydroxyapatite phase originating from CaCO3, and the ratios of calcium to phosphate were tracked over time. Variations in the weight portion of the components in the hybrid gels before and after the phase transformation of the CaCO3 templates were identified via thermogravimetric analysis (TGA). Scanning electron microscopy (SEM) shows these composite hydrogels have a unique multiscale microstructure consisting of a collagen nanofibril network and hydroxyapatite microspheres. The relationship between the hydroxyapatite nanocrystals and the collagen fibrils was revealed by transmission electron microscopy (TEM) in detail, and the selected area electron diffraction (SAED) pattern further confirmed the results of the XRD analyses which show the typical low crystallinity of the generated hydroxyapatite. This smart synthesis strategy achieved the simultaneous construction of microscale hydroxyapatite particles and collagen fibrillar hydrogel, and appears to provide a novel route to explore an advanced functional hydrogel materials with promising potentials for applications in bone tissue engineering and reconstruction medicine.

Collagen and hyaluronic acid hydrogel in water-in-oil microemulsion delivery systems.

Science.gov (United States)

Kupper, Sylwia; Kłosowska-Chomiczewska, Ilona; Szumała, Patrycja

2017-11-01

The increase in skin related health issues has promoted interest in research on the efficacy of microemulsion in dermal and transdermal delivery of active ingredients. Here, we assessed the water-in-oil microemulsion capacity to incorporate two natural polymers, i.e. collagen and hyaluronic acid with low and high molecular weight. Systems were extensively characterized in terms of conductivity, phase inversion studies, droplet diameter, polydispersity index and rheological properties. The results of this research indicate that the structure and extent of water phase in microemulsions is governed by ratio and amount of surfactant mixture (sorbitan ester derivatives). However, results have also shown that collagen, depending upon the weight of the molecule and its surface activity, influence the droplet size of the microemulsions. While the hyaluronic acid, especially with high molecular weight, due to the water-binding ability and hydrogel formation alters the rheological properties of the microemulsion, thus providing viscous consistency of the formulation. Copyright © 2017 Elsevier Ltd. All rights reserved.

A urokinase receptor-associated protein with specific collagen binding properties

DEFF Research Database (Denmark)