scholarly journals Influence of Collagen and Chondroitin Sulfate (CS) Coatings on Poly-(Lactide-co-Glycolide) (PLGA) on MG 63 Osteoblast-Like Cells

2011 ◽  
pp. 797-813 ◽  
Author(s):  
M. VANDROVCOVÁ ◽  
T. DOUGLAS ◽  
D. HAUK ◽  
B. GRÖSSNER-SCHREIBER ◽  
J. WILTFANG ◽  
...  

Poly-(lactide-co-glycolide) (PLGA) is an FDA-approved biodegradable polymer which has been widely used as a scaffold for tissue engineering applications. Collagen has been used as a coating material for bone contact materials, but relatively little interest has focused on biomimetic coating of PLGA with extracellular matrix components such as collagen and the glycosaminoglycan chondroitin sulfate (CS). In this study, PLGA films were coated with collagen type I or collagen I with CS (collagen I/CS) to investigate the effect of CS on the behaviour of the osteoblastic cell line MG 63. Collagen I/CS coatings promoted a significant increase in cell number after 3 days (in comparison to PLGA) and after 7 days (in comparison to PLGA and collagen-coated PLGA). No influence of collagen I or collagen I/CS coatings on the spreading area after 1 day of culture was observed. However, the cells on collagen I/CS formed numerous filopodia and displayed well developed vinculin-containing focal adhesion plaques. Moreover, these cells contained a significantly higher concentration of osteocalcin, measured per mg of protein, than the cells on the pure collagen coating. Thus, it can be concluded that collagen I/CS coatings promote MG 63 cell proliferation, improve cell adhesion and enhance osteogenic cell differentiation.

2008 ◽  
Vol 2008 ◽  
pp. 1-8 ◽  
Author(s):  
Yoshihiro Akimoto ◽  
Hajime Sawada ◽  
Mica Ohara-Imaizumi ◽  
Shinya Nagamatsu ◽  
Hayato Kawakami

We examined changes in the ultrastructure and localization of major extracellular matrix components, including 5 types of collagen (type I, III, IV, VI, and VIII), laminin, fibronectin, and heparan sulfate proteoglycan in Descemet's membrane of the cornea of diabetic GK rats. In the cornea of diabetic GK rats, more long-spacing collagen fibrils were observed in Descemet's membrane than in the membrane of the nondiabetic Wistar rats. Both GK and Wistar rats showed an age-dependent increase in the density of the long-spacing collagen. Immunoelectron microscopy showed that type VIII collagen was localized in the internodal region of the long-spacing collagen, which was not labelled by any of the other antibodies used. The antidiabetic agents nateglinide and glibenclamide significantly suppressed the formation of the long-spacing collagen in the diabetic rats. Long-spacing collagen would thus be a useful indicator for studying diabetic changes in the cornea and the effect of antidiabetic agents.


2020 ◽  
Vol 133 (23) ◽  
pp. jcs248278 ◽  
Author(s):  
Ana M. Diaz-Espinosa ◽  
Patrick A. Link ◽  
Delphine Sicard ◽  
Ignasi Jorba ◽  
Daniel J. Tschumperlin ◽  
...  

ABSTRACTMatrix resorption is essential to the clearance of the extracellular matrix (ECM) after normal wound healing. A disruption in these processes constitutes a main component of fibrotic diseases, characterized by excess deposition and diminished clearance of fibrillar ECM proteins, such as collagen type I. The mechanisms and stimuli regulating ECM resorption in the lung remain poorly understood. Recently, agonism of dopamine receptor D1 (DRD1), which is predominantly expressed on fibroblasts in the lung, has been shown to accelerate tissue repair and clearance of ECM following bleomycin injury in mice. Therefore, we investigated whether DRD1 receptor signaling promotes the degradation of collagen type I by lung fibroblasts. For cultured fibroblasts, we found that DRD1 agonism enhances extracellular cleavage, internalization and lysosomal degradation of collagen I mediated by cathepsin K, which results in reduced stiffness of cell-derived matrices, as measured by atomic force microscopy. In vivo agonism of DRD1 similarly enhanced fibrillar collagen degradation by fibroblasts, as assessed by tissue labeling with a collagen-hybridizing peptide. Together, these results implicate DRD1 agonism in fibroblast-mediated collagen clearance, suggesting an important role for this mechanism in fibrosis resolution.This article has an associated First Person interview with the first author of the paper.


2011 ◽  
Vol 300 (4) ◽  
pp. C907-C918 ◽  
Author(s):  
Matilde Alique ◽  
Laura Calleros ◽  
Alicia Luengo ◽  
Mercedes Griera ◽  
Miguel Ángel Iñiguez ◽  
...  

Glomerular diseases are characterized by a sustained synthesis and accumulation of abnormal extracellular matrix proteins, such as collagen type I. The extracellular matrix transmits information to cells through interactions with membrane components, which directly activate many intracellular signaling events. Moreover, accumulating evidence suggests that eicosanoids derived from cyclooxygenase (COX)-2 participate in a number of pathological processes in immune-mediated renal diseases, and it is known that protein kinase B (AKT) may act through different transcription factors in the regulation of the COX-2 promoter. The present results show that progressive accumulation of collagen I in the extracellular medium induces a significant increase of COX-2 expression in human mesangial cells, resulting in an enhancement in PGE2 production. COX-2 overexpression is due to increased COX-2 mRNA levels. The study of the mechanism implicated in COX-2 upregulation by collagen I showed focal adhesion kinase (FAK) activation. Furthermore, we observed that the activation of the phosphatidylinositol 3-kinase (PI3K)/AKT pathway by collagen I and collagen I-induced COX-2 overexpression was abolished by PI3K and AKT inhibitors. Additionally, we showed that the cAMP response element (CRE) transcription factor is implicated. Finally, we studied COX-2 expression in an animal model, NG-nitro-l-arginine methyl ester hypertensive rats. In renal tissue and vascular walls, COX-2 and collagen type I content were upregulated. In summary, our results provide evidence that collagen type I increases COX-2 expression via the FAK/PI3K/AKT/cAMP response element binding protein signaling pathway.


2021 ◽  
Vol 73 (1) ◽  
pp. 103-110
Author(s):  
Braca Kundalic ◽  
Sladjana Ugrenovic ◽  
Ivan Jovanovic ◽  
Vladimir Petrovic ◽  
Aleksandar Petrovic ◽  
...  

The aim of this study was to analyze the expression of extracellular matrix (ECM) proteins in human endoneurium during aging. We harvested 15 cadaveric sural nerves, distributed in 3 age groups (I: 25-44, II: 45-64, III: 65-86 years old). Histological sections were stained immunohistochemically for the presence of collagen type I, type IV and laminin, and the ImageJ processing program was used in morphometrical analysis to determine the percentages of these endoneurial proteins. In two younger groups, the endoneurial matrix of the sural nerve was composed from about equal proportions of these proteins, which may be considered a favorable microenvironment for the regeneration of nerve fibers. Linear regression analysis showed a significant increase in endoneurial collagen type IV with age, while collagen type I and laminin significantly decreased during the aging process. In cases older than 65 years, remodeling of the endoneurial matrix was observed to be significantly higher for the presence of collagen type IV, and lower for the expression of collagen type I and laminin. This age-related imbalance of ECM proteins could represent a disadvantageous microenvironment for nerve fiber regeneration in older adults. Our findings contribute to the development of therapeutic approaches for peripheral nerve regeneration.


2012 ◽  
Vol 23 (10) ◽  
pp. 1955-1963 ◽  
Author(s):  
Justin Lengfeld ◽  
Qiwei Wang ◽  
Andrew Zohlman ◽  
Susana Salvarezza ◽  
Stephanie Morgan ◽  
...  

Collagen type I is the most abundant component of extracellular matrix in the arterial wall. Mice knocked out for the protein kinase C δ gene (PKCδ KO) show a marked reduction of collagen I in the arterial wall. The lack of PKCδ diminished the ability of arterial smooth muscle cells (SMCs) to secrete collagen I without significantly altering the intracellular collagen content. Moreover, the unsecreted collagen I molecules accumulate in large perinuclear puncta. These perinuclear structures colocalize with the trans-Golgi network (TGN) marker TGN38 and to a lesser degree with cis-Golgi marker (GM130) but not with early endosomal marker (EEA1). Associated with diminished collagen I secretion, PKCδ KO SMCs exhibit a significant reduction in levels of cell division cycle 42 (Cdc42) protein and mRNA. Restoring PKCδ expression partially rescues Cdc42 expression and collagen I secretion in PKCδ KO SMCs. Inhibition of Cdc42 expression or activity with small interfering RNA or secramine A in PKCδ WT SMCs eliminates collagen I secretion. Conversely, restoring Cdc42 expression in PKCδ KO SMCs enables collagen I secretion. Taken together, our data demonstrate that PKCδ mediates collagen I secretion from SMCs, likely through a Cdc42-dependent mechanism.


2021 ◽  
Vol 8 (8) ◽  
pp. 201955
Author(s):  
Virginia L. Harvey ◽  
Joseph N. Keating ◽  
Michael Buckley

Ray-finned fishes (Actinopterygii) are the largest and most diverse group of vertebrates, comprising over half of all living vertebrate species. Phylogenetic relationships between ray-finned fishes have historically pivoted on the study of morphology, which has notoriously failed to resolve higher order relationships, such as within the percomorphs. More recently, comprehensive genomic analyses have provided further resolution of actinopterygian phylogeny, including higher order relationships. Such analyses are rightfully regarded as the ‘gold standard’ for phylogenetics. However, DNA retrieval requires modern or well-preserved tissue and is less likely to be preserved in archaeological or fossil specimens. By contrast, some proteins, such as collagen, are phylogenetically informative and can survive into deep time. Here, we test the utility of collagen type I amino acid sequences for phylogenetic estimation of ray-finned fishes. We estimate topology using Bayesian approaches and compare the congruence of our estimated trees with published genomic phylogenies. Furthermore, we apply a Bayesian molecular clock approach and compare estimated divergence dates with previously published genomic clock analyses. Our collagen-derived trees exhibit 77% of node positions as congruent with recent genomic-derived trees, with the majority of discrepancies occurring in higher order node positions, almost exclusively within the Percomorpha. Our molecular clock trees present divergence times that are fairly comparable with genomic-based phylogenetic analyses. We estimate the mean node age of Actinopteri at ∼293 million years (Ma), the base of Teleostei at ∼211 Ma and the radiation of percomorphs beginning at ∼141 Ma (∼350 Ma, ∼250–283 Ma and ∼120–133 Ma in genomic trees, respectively). Finally, we show that the average rate of collagen (I) sequence evolution is 0.9 amino acid substitutions for every million years of divergence, with the α 3 (I) sequence evolving the fastest, followed by the α 2 (I) chain. This is the quickest rate known for any vertebrate group. We demonstrate that phylogenetic analyses using collagen type I amino acid sequences generate tangible signals for actinopterygians that are highly congruent with recent genomic-level studies. However, there is limited congruence within percomorphs, perhaps due to clade-specific functional constraints acting upon collagen sequences. Our results provide important insights for future phylogenetic analyses incorporating extinct actinopterygian species via collagen (I) sequencing.


2001 ◽  
Vol 12 (12) ◽  
pp. 2701-2710
Author(s):  
Fadi Fakhouri ◽  
Sandrine Placier ◽  
Raymond Ardaillou ◽  
Jean-Claude Dussaule ◽  
Christos Chatziantoniou

ABSTRACT. Hypertension is frequently associated with the development of renal vascular fibrosis. This pathophysiologic process is due to the abnormal formation of extracellular matrix proteins, mainly collagen type I. In previous studies, it has been observed that the pharmacologic blockade of angiotensin II (Ang II) or endothelin (ET) blunted the development of glomerulo- and nephroangiosclerosis in nitric oxide-deficient hypertensive animals by inhibiting collagen I gene activation. The purpose of this study was to investigate whether and how AngII interacts with ET to activate the collagen I gene and whether transforming growth factor-β (TGF-β) could be a player in this interaction. Experiments were performedin vivoon transgenic mice harboring the luciferase gene under the control of the collagen I-α2 chain promoter (procolα2[I]). Bolus intravenous administration of AngII or ET produced a rapid, dose-dependent activation of collagen I gene in aorta and renal cortical slices (threefold increase over control at 2 h,P< 0.01). The AngII-induced effect on procolα2(I) was completely inhibited by candesartan (AngII type 1 receptor antagonist) and substantially blunted by bosentan (dual ET receptor antagonist) (P< 0.01), whereas the ET-induced activation of collagen I gene was blocked only by bosentan. In subsequent experiments, TGF-β (also administered intravenously) produced a rapid increase of procolα2(I) in aorta and renal cortical slices (twofold increase over control at 1 h,P< 0.01) that was completely blocked by decorin (scavenger of the active form of TGF-β). In addition, decorin attenuated the activation of collagen I gene produced by AngII (P< 0.01). These data indicate that AngII can activate collagen I gene in aorta and renal cortexin vivoby a mechanism(s) requiring participation and/or cooperation of ET and TGF-β.


2002 ◽  
Vol 13 (4) ◽  
pp. 928-936 ◽  
Author(s):  
Masaomi Nangaku ◽  
Jeffrey Pippin ◽  
William G. Couser

ABSTRACT. Although it was once considered only a marker of glomerular damage, accumulating evidence indicates that proteinuriaper seis nephrotoxic and contributes to the progression of renal injury. Several studies have demonstrated that activation of complement in proteinuric urine results in tubular and interstitial damage. It was previously demonstrated that acute complement-mediated interstitial disease is induced by C5b-9. Here the role of C5b-9 in the progression of chronic proteinuric renal disease was investigated in a nonimmunologic remnant kidney model. Five-sixths nephrectomies were performed for normocomplementemic control and C6-deficient PVG rats. Tubulointerstitial injury was assessed by measurement of two independent markers of tubular injury (i.e., vimentin and osteopontin), interstitial accumulation of the extracellular matrix components collagen type I, collagen type IV, and laminin, interstitial macrophage infiltration, and renal function. The two groups developed similar levels of proteinuria and BP. Whereas C3 deposition on the brush border was equivalent for rats in the two groups, C5b-9 deposition was observed only for normocomplementemic rats. At day 35, the degrees of both tubulointerstitial injury and renal failure were the same for the two groups. Tubulointerstitial injury in normocomplementemic rats was still severe at day 70. In contrast, interstitial injury in C6-deficient rats had improved markedly at day 70, with improvements in renal function. In a rat model of chronic progressive renal disease secondary to nephron loss, the initial interstitial changes are complement-independent and largely reversible, whereas progressive interstitial fibrosis is mediated predominantly by C5b-9. Treatment to reduce C5b-9 attack in tubular cells may slow progression and facilitate recovery.


2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Jinglue Song ◽  
Hongli Liu ◽  
Qi Zhu ◽  
Yutong Miao ◽  
Feiyan Wang ◽  
...  

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease characterized by bone loss. Degree of inflammation has been identified as an important initiator of skeletal damage in RA. Iguratimod (T-614) is an anti-inflammatory agent which has been reported to show the inhibitory effect of bone destruction in RA. However, the role of T-614 in osteoblast differentiation is still not clear. In this study, we intended to find the effect of T-614 on the osteogenesis process. We detected osteogenesis markers and transcription factors associated with osteoblastic lineage and bone formation in the culture of mesenchymal stem cells which differentiate osteoblast. The contents and activity of alkaline phosphatase, levels of collagen type I and bone gla protein, and calcium nodule formation were increased significantly after T-614 treated. Meanwhile, the mRNAs expressions of Osterix and Dlx5 were also found to be increased significantly by real-time PCR. The changes of levels of phosphorylation of p38 and NF-κB were also detected by Western blot. The results showed that T-614 promotes osteoblastic differentiation by increasing the expression of Osterix and Dlx5 and increasing the activation of P38. T-614 could advance the ectopic expression of NF-κB to suppress inflammation, which indirectly inhibits the damage of the osteoblasts.


Sign in / Sign up

Export Citation Format

Share Document