Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.3 (collagenase)
 18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Three-dimensional elastic substrates were fabricated from a commercially available polyurethane with an internal porosity of approximately 70% and elastic modulus of 27.4+/-2.76 KPa and examined for suitability in vocal fold tissue engineering. Using immunohistochemistry, biomechanical testing, and RT-PCR; we examined human fibroblast viability, distribution and extracellular matrix related gene expression within substrates for periods up to 4 weeks. We found that cells were capable of colonizing the entire volume of a 5mm wide x 3mm deep x 20mm long substrate at high viability. Histological cross-sections showed extensive extracellular matrix deposited around the cells and throughout the pore structure of the substrates, which consisted of fibronectin and type I collagen. Cell seeded substrates displayed a significantly higher elastic modulus than unseeded controls similar to native tissue. The transfer of cell growth from two-dimensional to three-dimensional culture resulted in changes in ECM-related gene expression consistent with decreasing cell migration and increasing tissue formation. We found that fibroblasts cultured in three-dimensional substrates expressed significantly higher levels of mRNA for elastin and fibromodulin, while expressing significantly lower levels of mRNA for MMP-1 and hyaluronidase relative to two-dimensional substrates of the same material. The results suggest that three-dimensionally porous, Tecoflex-derived elastic biomaterials may be suitable substrates for engineering vocal fold tissue.
 ...
PMID:Comparison of human fibroblast ECM-related gene expression on elastic three-dimensional substrates relative to two-dimensional films of the same material. 1295 Oct 11

The small GTPases of the Rho family are key intermediates in cellular signalling triggered by activated cell-adhesion receptors. In this study, we took advantage of RNA interference (RNAi) using small interfering RNAs (siRNAs) to define the roles of the best-characterized members of the RhoGTPase family, RhoA, Rac1 and Cdc42, in the control of MMP-1, MMP-2 and type-I-collagen expression in normal human skin fibroblasts (HSFs). A specific and long-lasting repression, up to 7 days after transfection, of the three GTPases was achieved by transient transfection of specific siRNA. The silencing of Cdc42, but not that of RhoA or Rac1, induced a 15-fold increase in MMP-1 secretion. This upregulation was confirmed at the mRNA level and observed with two different siRNAs targeting Cdc42. Such a regulation was also observed in various human cell lines and was rescued by re-expressing wild-type Cdc42 encoded by a construct bearing silent mutations impeding its recognition by the siRNA. By contrast, MMP-2 and type-I-collagen expression was not affected by the individual silencing of each Rho GTPase. Cytokine protein array, enzyme-linked immunosorbent assays and reverse-transcription PCR measurements revealed that ablation of Cdc42 induced an overexpression of interleukin 8 and MCP-1. Although these cytokines are known to induce the expression of MMP-1, we showed that they were not involved in the Cdc42-mediated upregulation of MMP-1. Silencing of Cdc42 also induced an increased phosphorylation of ERK1/2 and p38 MAP kinase. The use of chemical inhibitors on Cdc42-ablated cells revealed that the upregulation of MMP-1 is dependent on the ERK1/2 pathways, whereas the p38 MAP kinase pathway displayed an inhibitory role. Simultaneous knock-down of two or three Rho GTPases allowed us to demonstrate that the RhoA-ROCK pathway was not involved in this regulation but that the silencing of Rac1 reduced the effect of Cdc42 suppression. These data suggest that, in vivo, when cell/extracellular-matrix interactions via integrins induce cytoskeleton organization, MMP-1 expression is maintained at a low level by Cdc42 via a repression of the Rac1 and ERK1/2 pathways. Therefore, Cdc42 contributes to ECM homeostasis and connective tissue integrity.
 ...
PMID:Cdc42 downregulates MMP-1 expression by inhibiting the ERK1/2 pathway. 1572 53

When bone is loaded, substrate strain is generated by the external force and this strain induces fluid flow that creates fluid shear stress on bone cells. Our current understanding of load-driven gene regulation of osteoblasts is based primarily on in vitro studies on planer two-dimensional tissue culture substrates. However, differences between a flat layer of cells and cells in 3-dimensional (3D) ECM are being recognized for signal transduction. Proliferation and differentiation of osteoblasts are affected by substrate geometry. Here we developed a novel 3D culture system that would mimic physiologically relevant substrate strain as well as strain-induced fluid flow in a 3D porous collagen matrix. The system allowed us to evaluate the responses of osteoblasts in a 3D stress-strain environment similar to a mechanical field to which bone is exposed. Using MC3T3-E1 osteoblasts grown in the 3D collagen matrix with and without hydroxyapatite deposition, we tested the role of strain and the strain-induced fluid flow in the expression of the load-responsive genes such as c-fos, egr1, cox2, osteopontin, and mmp1B involved in transcriptional regulation, osteogenesis, and rearrangement of ECM. Strain-induced fluid flow was visualized with a microspheres approximately 3 microm in diameter in real time, and three viscoelastic parameters were determined. The results obtained by semi-quantitative PCR, immunoblot assay, enzymatic activity assays for collagenase and gelatinase, and mechanical characterization of collagen matrices supported the dominant role of strain-induced fluid flow in expression of the selected genes one hour after the mechanical treatment.
 ...
PMID:Osteoblast responses one hour after load-induced fluid flow in a three-dimensional porous matrix. 1581 78

Matrix metalloproteinase-8 (MMP-8), also known as collagenase-2 or neutrophil collagenase, was long thought to be expressed solely by maturing neutrophils, and functionally restricted to ECM breakdown. Recent experiments, however, have revealed that this protease can be expressed by a wide variety of cell types and that it plays an important regulatory role in both acute and chronic inflammation. This review intends to give the reader an overview of the most interesting recent findings concerning the role of MMP-8 in inflammation and in cancer progression.
 ...
PMID:Matrix metalloproteinase-8: cleavage can be decisive. 1682 Mar 17

Collagen type II (Col II), one of the main components of the hyaline cartilage, is a member of the fibril-forming collagen family. Due to its amino acid composition, the extent of lysine hydroxylation of Col II is much higher than that of other fibril forming collagens. Since lysyl hydroxylase isoforms are less synthesized in hypothyroid ovarian tissue, Col II level is expected to be reduced here and contribute to the degradation of ovarian ECM in this condition. As there was no previous report, we have demonstrated Col II expression in rat ovary. Col2A1 mRNA shares significant part of the total collagens in ovary as shown by the relative expression of the major collagen genes present in this tissue. It has also been shown that Col II is down regulated in hypothyroid ovarian tissue and its expression is increased upon stimulation by thyroid hormone (T(3)). To know whether less Col II in hypothyroid ovarian tissue is due to less synthesis of the protein or its increased rate of degradation is also involved in it, we demonstrated the status of Collagen - degrading Matrix Metalloproteinases in this condition and found up regulation of MMP-1, -8 and -13 in hypothyroid rat ovary. The present study shows the reduced Col II expression in hypothyroid rat ovary, with the concomitant increase in Col II degradation. This information will be useful for further studies on reproductive disorders.
 ...
PMID:Localization and thyroid hormone influenced expression of collagen II in ovarian tissue. 1731 Jan 1

The extracellular matrix of solid tumors presents a transport barrier that restricts nanoparticle penetration, thereby limiting the efficacy of nano-sized delivery vehicles for cancer imaging and therapy. In this study, the effect of nanoparticle size and collagenase treatment on penetration of carboxylated polystyrene nanoparticles was systematically assessed in a multicellular spheroid model. Penetration of the nanoparticles into the spheroid core was limited to particles smaller than 100 nm. Collagenase treatment of spheroids resulted in significantly increased penetration of nanoparticles up to 100 nm with only a minor increase in particle penetration observed for particles larger than 100 nm. Collagenase was immobilized onto the surface of nanoparticles for site-specific degradation of ECM proteins. Collagenase-coated, 100 nm nanoparticles demonstrated a 4-fold increase in the number of particles delivered to the spheroid core compared with control nanoparticles. Thus, nanoparticle delivery to solid tumors may be substantially improved by the incorporation of ECM-modulating enzymes in the delivery formulation.
 ...
PMID:Increased nanoparticle penetration in collagenase-treated multicellular spheroids. 1772 54

Matrix metalloproteinases (MMPs) have an important role in the initiation, growth, and invasion of malignant tumors. Basal cell cancer (BCC) is the most common human malignancy. The risk of BCC is 10-16 times higher among organ transplant recipients compared with the nontransplanted population. The aim of this study was to compare the expression of several MMPs and their tissue inhibitors (TIMPs) in BCCs from kidney transplant recipients and controls. Expression of MMPs-1, -7, -8, -9, -10, -13, -26, and TIMPs-1 and -3 was evaluated by immunohistochemistry in 25 samples of BCC of kidney transplant recipients and 25 matched controls representing superficial and nodular subtypes. No significant differences were detected in MMP expression of BCC tumor cells between immunocompetent and immunodeficient patients. However, MMPs-1 and -9 and TIMP-1 were expressed more frequently in stromal macrophages in the BCCs of immunocompetent patients. When tumor subtypes were compared irrespective of the patient group, more MMP-1-positive fibroblasts and MMP-9-positive neutrophils were detected in the superficial subtype, while stromal MMP-10 expression was more abundant in nodular tumors. Our results suggest that abundant peritumoral expression of TIMP-1 in non-immunocompromised patients limits ECM degradation permissive for cancer cell migration.
 ...
PMID:Differential expression of stromal MMP-1, MMP-9 and TIMP-1 in basal cell carcinomas of immunosuppressed patients and controls. 1803 64

Increased levels of MMP-8 (neutrophil collagenase) have been reported in OB, but the biological role of MMP-8 in OB is not known. MMP-8 is an interstitial collagenase highly expressed by polymorphonuclear leukocytes, which are prominent in early OB. Here, we show that MMP-8 promotes migration of PMNs through the collagen-rich matrix in a mouse heterotopic airway transplant model of OB. Overall, MMP-8(-/-) mice had significantly fewer PMNs in the airway lumen 2 and 14 days post-transplantation, and the percentage of PMNs traversing the matrix to the lumen was decreased markedly in the MMP-8(-/-) compared with WT mice at 14 days. There were significantly more PMNs outside of the lumen in the ECM in the MMP-8(-/-) mice compared with WT mice. In vitro, significantly fewer MMP-8(-/-) PMNs migrated through 3D cross-linked collagen gels than WT PMNs. MMP inhibitor GM6001 was also able to impede migration of WT PMNs through collagen gels. The decreased migration was likely a result of pericollagenase activity of MMP-8, as WT PMNs expressing MMP-8 were not able to migrate effectively through collagen that was resistant to the collagenase. Protection from OB was seen in the MMP-8(-/-) mice, as the airway lumen had significantly less obliteration and collagen deposition, suggesting that MMP-8 plays an important role in the pathogenesis of OB.
 ...
PMID:MMP-8 promotes polymorphonuclear cell migration through collagen barriers in obliterative bronchiolitis. 2004 88

An alternative non-vascular extracellular material was obtained by decellularisation of porcine urinary bladder and examined for its potential as scaffold for vascular tissue engineering. Analysis using Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and Laser Scanning Microscopy (LSCM) showed a porous interconnective microarchitecture, an abundance of well preserved fibers on the abluminal side and a micropatterned flat luminal surface. Uniaxial tensile testing revealed a strength of 1.9+/-0.3 MPa for the rehydrated material in a phosphate buffered saline medium for the ECM-UBM sheet and these results comparable to those of native artery of a middle aged human. Multilamination of the UBM increases the tensile properties in general (9+/-0.45 MPa for 2 layer, 30+/-0.6 MPa for 4 layers construct), with no effect on elongation capacities (38-40%) of the material. Contact-angle measurements indicated that the ECM-UBM surface exhibited a hydrophylic characteristic and better wettability than any vascular synthetic materials. Comparison of the initial adhesion in the multiplayer ECM constructs was evaluated and was found not to be altered by the preparation. The HAECs and HSMC shown an excellent adherence, spread and proliferation on the ECM-UBM material with the preservation of the cell phenotype. The level of MMP-1 and MMP-9 produced by endothelial cells was evaluated in this study and provides some data on the remodelling capacity of the scaffold. Vascular cell seeded-UBM constructs may also provide a suitable and affordable in vitro model for cell-physiology and drug development studies, which may elucidate to the mechanisms of vascular disease formation, and its prevention and treatment.
 ...
PMID:Extracellular matrices as advanced scaffolds for vascular tissue engineering. 2004

Liver fibrosis (LF), where the chronic HCV infection is a major cause, is a characteristic of chronic liver diseases. LF results from chronic damage to the liver in conjunction with the accumulation of ECM proteins. Matrix metalloproteinases (MMPs) and their specific inhibitors (TIMPs) are thought to play an essential role in the hepatic lesions. The available data concerning the circulating levels of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in chronic hepatitis C are not conclusive. Therefore, the present study was designed to seek the relationship between serum MMP-9, and TIMP-1 to liver status in chronic liver disease in fifty patients divided into three groups (chronic hepatitis, liver cirrhosis and hepatocellular carcinoma). MMP-9 and TIMP-1 were analyzed by the enzyme linked immunosorbent assay (ELISA). The results showed that the lowest serum level of MMP-9 was found in chronic hepatitis patients compared to the control ( P < 0.05). Serum MMP-9 is decreasing during progression of chronic hepatitis to cirrhosis showing the least level in the cirrhotic group. Serum TIMP-1 was significantly higher in the cirrhotic group compared to chronic hepatitis ( P < 0.05) and controls ( P < 0.001). MMP-9 was negatively correlated to both TIMP-1 and the histological severity in chronic hepatitis. There was a positive correlation between TIMP-1 and the degree of fibrosis (r = 0.73, P < 0.001). Lastly, there was a statistically significant increase of MMP-9 ( P < 0.001) and TIMP-1 ( P < 0.05) in HCC patients compared with the other groups. In conclusion, these findings raise the possibility of using serum TIMP-1 as a non-invasive assay in liver fibrosis. Further, the altered balance between circulating MMP-9 and TIMP-1 during HCV infection may play an important role in aggravating liver injury progression in chronic liver diseases.
 ...
PMID:Significance of serum matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 in chronic hepatitis C patients. 2035 Aug 77


<< Previous 1 2 3 4 5 6 7 Next >>