Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Expansion of the mesangial matrix in diabetes occurs after prolonged exposure to the diabetic milieu. To mimic the long-term hyperglycemia of diabetes mellitus we developed tissue culture systems that might approximate the chronic state. This was accomplished in two ways: (1) by growing mesangial cells on extracellular matrix glycated and crosslinked in vitro and (2) by continuously growing cells on their own matrix on filters in elevated glucose medium (500 mg/dl) for up to eight weeks without passage. Synthesis of collagen and proteoglycans was evaluated in cells grown under these conditions. In both these situations, 3H-proline incorporation into collagenase sensitive protein and 35S incorporation into sulfated proteins were reduced compared to control cultures. Despite reduction in 35S incorporation into proteoglycans in the high glucose cultures, total glycosaminoglycan content was unchanged. However, proteoglycans generated by mesangial cells grown in elevated glucose media were of a lower negative charge than controls. In mesangial cells continuously grown on filters, the levels of messenger RNA for collagen types I and IV, biglycan and TGF-beta were not different in cells grown at elevated or standard glucose concentrations for two and four weeks. We conclude that crosslinking of mesangial matrix or continuous culture of cells for prolonged periods of time in high glucose medium, which may also crosslink matrix, suppresses collagen synthesis and reduces the negative charges on matrix proteoglycans without altering mRNA levels.
...
PMID:Nonenzymatic glycation of mesangial matrix and prolonged exposure of mesangial matrix to elevated glucose reduces collagen synthesis and proteoglycan charge. 847 21

Knee laxity has been shown to increase during human pregnancy, and the laxity of the rabbit medial collateral ligament also increases during pregnancy. To determine whether the changes in tissue function could be related to alterations in the regulation of gene expression for a subset of relevant molecules in ligaments, RNA was isolated from the medial collateral(MCL) and anterior cruciate(ACL) ligaments of first time pregnant adolescent rabbits. Levels of mRNA for matrix molecules (collagen types I and III and the proteoglycans biglycan, decorin, versican and lumican), proteinases and inhibitors (collagenase, urokinase, PAI-1 and TIMP-1, -2 and -3), growth factors (bFGF, IGF-I, TGF-beta1 and ET-1), cytokines (IL-1beta and TNF) and enzymes responsible for important tissue mediators (COX-2 and iNOS) were assessed by semi-quantitative RT-PCR. In the MCL, levels of transcripts for all of the matrix molecules, growth factors and TIMPs 1 and 2 were significantly depressed at 29 days of pregnancy compared to age-matched non-pregnant controls. In contrast, transcripts for PAI-1 were elevated during pregnancy, while those for collagenase (MMP-1), urokinase, TIMP-3, IL-1beta, TNF, COX-2 and iNOS were not statistically altered. mRNA transcript levels rebounded by 7 days post-partum for most genes studied, indicating that the changes were rapidly reversible. For some molecules, transcript levels were again depressed at 18 days post-partum, indicating that regulatory mechanisms were still not stabilized. Analysis of mRNA from the ACL also revealed changes in the pattern of gene expression, with some similarities and differences from the MCL noted. These results indicate that pregnancy induces reversible changes in mRNA for matrix molecules in ligaments, but differences in responsiveness exist between different ligaments. The complexity of the changes observed indicates that there is probably no simple cause and effect relationship between laxity changes and the molecular alterations during pregnancy.
...
PMID:Pregnancy induces complex changes in the the pattern of mRNA expression in knee ligaments of the adolescent rabbit. 962 50

Midsubstance samples of anterior cruciate ligaments from seven normal human cadaver knees (16-50 years old) were harvested and compared with midsubstance pieces of scarred anterior cruciate ligaments from 30 patients (15-40 years old). RNA was isolated from each ligament, and the expression of type-I collagen, type-III collagen, biglycan, decorin, lumican, and tissue inhibitor of metalloproteinase-1 was evaluated by quantitative reverse transcription-polymerase chain reaction with use of beta-actin as the housekeeping gene. Data for injured ligaments were further compared statistically as a function of time after injury to better define patterns of cellular expression over time. Our hypothesis was that injured ligaments would show minimal cellular activity and decreasing activity over time. The results revealed that both normal and injured anterior cruciate ligaments contain cells that express mRNA for all molecules studied. However, cells in injured ligaments express much higher, but still proportional, quantities of message for type-I collagen and type-III collagen (p < 0.000001) and higher quantities of biglycan (p < 0.02) and tissue inhibitor of metalloproteinase-1 (p < 0.0003) than do cells in normal anterior cruciate ligaments. These levels remained elevated for longer than 1 year after injury. Linear regression analysis showed biglycan expression correlated with time from injury (r2 = -0.69; p = 0.007). These results collectively demonstrate that injured human anterior cruciate ligaments contain cells that express scar-like molecules and that the injured ligaments are likely continuing to remodel matrix over time. Furthermore, they suggest that human anterior cruciate ligaments have not failed to heal due to the failure of scar formation per se. The quality and quantity of this scar remain questionable; however, the possibility of its enhancement as a healing strategy for human anterior cruciate ligaments cannot be dismissed.
...
PMID:Comparison of mRNA levels for matrix molecules in normal and disrupted human anterior cruciate ligaments using reverse transcription-polymerase chain reaction. 974 82

Recently, we have shown that the tumor necrosis factor-alpha (TNF-alpha)-induced morphological change of EA.hy 926 human endothelial cells is associated with a decrease in the net synthesis of two proteoglycans (PGs), biglycan and syndecan-1, both of which have been suggested to play a role in cell adhesion. Here we have examined whether this phenotypic modulation of EA.hy 926 cells also involves altered expression of matrix metalloproteinases (MMPs) or their tissue inhibitors (TIMPs). We demonstrate that, when forming cobblestone-like monolayer cultures, these cells express and synthesize collagenase-1 (MMP-1), stromelysin-1 (MMP-3) and 72 kDa (MMP-2) and 92 kDa (MMP-9) gelatinases, all of which have previously been found in either normal or pathological human vascular wall. EA.hy 926 cells also express membrane-typel MMP (MT1-MMP), but not matrilysin (MMP-7) and collagenase-3 (MMP-13). As regards TIMPs, we show that these cells express TIMP-1 and TIMP-2, but not TIMP-3 or TIMP-4. Exposure of the cells to TNF-alpha changed the cell morphology from a polygonal shape into a spindle shape and also increased the mRNA levels of MMP-1, MMP-3 and MMP-9, but slightly decreased the MMP-2 mRNA level. No change at the mRNA level of MT1-MMP was observed. Similarly to unstimulated cultures, no mRNA for MMP-7 or MMP-13 was detected in the TNF-alpha treated cultures. TNF-alpha had no effect on the TIMP-1 and TIMP-2 mRNA levels and did not induce TIMP-3 or TIMP-4 expression. Gelatin zymography and Western blot analysis revealed that the increase observed at the mRNA level of MMP-3 and MMP-9 was similar to that of their net protein level; furthermore, the active form of MMP-1 was induced. Our results indicate that the TNF-alpha-induced morphological change of EA.hy 926 cells is associated not only with specific changes in the expression of PGs by the cells, but also with specific changes in the expression of MMPs.
...
PMID:Collagenase-1, stromelysin-1 and 92 kDa gelatinase are associated with tumor necrosis factor-alpha induced morphological change of human endothelial cells in vitro. 974 45

Renal pathology in mice that are transgenic for the murine albumin enhancer/promoter linked to a full-length porcine transforming growth factor-beta1 (TGF-beta1) gene has been described previously. In these mice, transgene expression is limited to the liver and the plasma level of TGF-beta is increased. The earliest renal pathologic change is glomerulosclerosis, at 3 wk of age, and this is followed by tubulointerstitial fibrosis. In this study, it was hypothesized that circulating TGF-beta1 increases renal extracellular matrix accumulation and activates local TGF-beta gene expression. Immunostaining at 5 wk revealed increased amounts of collagen I and III within the mesangium, glomerular capillary loops, and interstitium, while the amount of collagen IV was normal. Similarly, Northern analysis showed increased expression of mRNA encoding collagen I and III, as well as biglycan and decorin, while the expression of collagen IV was unchanged. These changes began as early as 1 wk of age, a time before the appearance of glomerulosclerosis. To evaluate matrix degradation, collagenase IV activity was evaluated by gelatin zymography and an increase in matrix metalloproteinase-2 was found. Finally, the production of tissue inhibitors of metalloproteinase was evaluated. Tissue inhibitor of metalloproteinase-1 (TIMP-1) mRNA was increased 18-fold, while TIMP-2 and TIMP-3 were unchanged. In 2-wk-old transgenic kidney, local expression of TGF-beta1, beta2, and beta3 protein was similar to wild-type mice. In 5-wk-old transgenic mice, TGF-beta1 and beta2 protein was present in increased amounts within glomeruli, and renal TGF-beta1 mRNA was increased threefold. It is concluded that elevated levels of circulating TGF-beta1 may act on the kidney to increase matrix protein production and decrease matrix remodeling. Only after glomerulosclerosis is established does local glomerular overproduction of TGF-beta become manifest.
...
PMID:Renal expression of fibrotic matrix proteins and of transforming growth factor-beta (TGF-beta) isoforms in TGF-beta transgenic mice. 1021 26

A bovine nasal-cartilage culture system has been utilized to analyse the catabolic events occurring in response to interleukin-1beta over a 14-day period. An early event following the start of interleukin-1 treatment was the release of glycosaminoglycan into the culture medium. This release was accompanied by the appearance in the tissue, and shortly thereafter also in the culture media, of a globular domain (G1)-containing aggrecan degradation product generated by the action of aggrecanase. Link protein was also released from the cartilage with a similar timeframe to that of the G1 fragment, although there was no evidence of its proteolytic degradation. By comparison with aggrecan, the small leucine-rich repeat proteoglycans decorin, biglycan and lumican showed a resistance to both proteolytic cleavage and release throughout the culture period. In contrast, fibromodulin exhibited a marked decrease in size after day 4, presumably due to proteolytic modification, but the major degradation product was retained throughout the culture period. Also in contrast with the early changes in the components of the proteoglycan aggregate, type II collagen did not display signs of extensive degradation until much later in the culture period. Collagen degradation products compatible with collagenase action first appeared in the medium by day 10 and increased thereafter. These data demonstrate that the leucine-rich repeat proteoglycans are resistant to proteolytic action during interleukin-1-stimulated cartilage catabolism, compared with aggrecan. This resistance and continued interaction with the surface of the collagen fibrils may help to stabilize the collagen fibrillar network and protect it from extensive proteolytic attack during the early phases of cartilage degeneration.
...
PMID:Resistance of small leucine-rich repeat proteoglycans to proteolytic degradation during interleukin-1-stimulated cartilage catabolism. 1021 95

We have previously shown that an intermittent mechanical strain regimen (5% elongation, 60 cycles/min, 15 min/h) that simulates fetal breathing movements stimulated fetal rat lung cell proliferation. Because normal lung growth requires proper coordination between cell proliferation and extracellular matrix (ECM) remodeling, we subjected organotypic cultures of fetal rat lung cells (day 19 of gestation, term = 22 days) to this strain regimen and examined alterations in ECM gene and protein expression. Northern analysis revealed that mechanical strain reduced messages for procollagen-alpha1(I) and biglycan and increased the levels of mRNA for collagen-alpha1(IV) and -alpha2(IV), whereas laminin beta-chain mRNA levels remained constant. Regardless of mRNA changes, mechanical strain increased the protein content of type I and type IV collagen as well as of biglycan in the medium. Mechanical strain did not affect gene expression of several matrix metalloproteinases (MMPs), such as MMP-1 (interstitial collagenase), MMP-2 (gelatinase A), and MMP-3 (stromelysin-1). Neither collagenase nor gelatinase (A and B) activities in conditioned medium were affected by mechanical strain. Tissue inhibitor of metalloproteinase activities in conditioned medium remained unchanged during the 48-h intermittent mechanical stretching. These data suggest that an intermittent mechanical strain differentially regulates gene and protein expression of ECM molecules in fetal lung cells. The observed increase in matrix accumulation appears to be mainly a result of an increased synthesis of ECM molecules and not of decreasing activity of degradative enzymes.
...
PMID:Differential regulation of extracellular matrix molecules by mechanical strain of fetal lung cells. 1033 28

The alginate bead culture system has been utilised by several groups to examine the in vitro proteoglycan (PG) metabolism of chondrocytes and intervertebral disc cells, but the nature of the PGs produced has not been examined in detail. This is largely due to the difficulty of separating the anionically charged sodium alginate support matrix from PGs which are similarly charged. In the present study ovine annulus fibrosus, transitional zone and nucleus pulposus cells were dissociated enzymatically from their respective matrices by sequential digestion with pronase/clostridial collagenase and DNAase and then cultured in alginate beads for 10 d. The beads were solubilised and subjected to DEAE Sepharose CL6B anion exchange chromatography to separate the sodium alginate bead support matrix material quantitatively from the disc cell PGs. The alginate free bead PGs were then subjected to composite agarose polyacrylamide gel electrophoresis to resolve PG populations and the PGs were transferred to nitrocellulose membranes by semidry electroblotting. The PGs were identified by probing the blots with a panel of antibodies to defined PG core protein and glycosaminoglycan side chain epitopes. Alginate beads of disc cells were also embedded in paraffin wax and 4 microm sections cut to immunolocalise decorin, biglycan, versican, and the 7-D-4 PG epitope within the beads. Decorin and biglycan had similar distributions in the beads, being localised on the cell surface whereas versican and the 7-D-4 PG epitope were immunolocalised interterritoriarly. This study is the first to demonstrate that ovine disc cells synthesise versican in alginate bead culture. Furthermore the immunoblotting studies also showed that a proportion of the 7-D-4 PG epitope was colocalised with versican.
...
PMID:Differential expression of proteoglycan epitopes by ovine intervertebral disc cells. 1100 11

To test the hypothesis that loading conditions can be used to engineer early ligament scar behaviors, we used an in vitro system to examine the effect that cyclic hydrostatic compression and cyclic tension applied to 6-week rabbit medial collateral ligament scars had on mRNA levels for matrix molecules, collagenase, and the proto-oncogenes c-fos and c-jun. Our specific hypothesis was that tensile stress would promote more normal mRNA expression in ligament whereas compression would lead to higher levels of mRNA for cartilage-like molecules. Femur (injured medial collateral ligament)-tibia complexes were subjected to a hydrostatic pressure of 1 MPa or a tensile stress of 1 MPa of 0.5 Hz for 1 minute followed by 14 minutes of rest. On the basis of a preliminary optimization experiment, this 15-minute testing cycle was repeated for 4 hours. Semiquantitative reverse transcription-polymerase chain reaction analysis was performed for mechanically treated medial collateral ligament scars with use of rabbit specific primer sets for types I, II, and III collagen, decorin, biglycan, fibromodulin, versican, aggrecan, collagenase, c-fos, c-jun, and a housekeeping gene, glyceraldehyde-3-phosphate dehydrogenase. Cyclic hydrostatic compression resulted in a statistically significant increase in mRNA levels of type-II collagen (171% of nonloaded values) and aggrecan (313% of nonloaded values) but statistically significant decreases in collagenase mRNA levels (35% of nonloaded values). Cyclic tension also resulted in a statistically significant decrease in collagenase mRNA levels (66% of nonloaded values) and an increase in aggrecan mRNA levels (458% of nonloaded values) but no significant change in the mRNA levels for the other molecules. The results show that it is possible to alter mRNA levels for a subset of genes in scar tissue by supplying unique mechanical stimuli in vitro and thus that further investigation of scar engineering for potential reimplantation appears feasible.
...
PMID:Compressive compared with tensile loading of medial collateral ligament scar in vitro uniquely influences mRNA levels for aggrecan, collagen type II, and collagenase. 1105 87

To test the hypothesis that loading conditions can be used to "engineer" ligament autograft behaviors, the effect of cyclic tension on the mRNA levels of matrix molecules and collagenase in in-vivo immobilized and mobilized 6-week rabbit medial collateral ligament (MCL) autografts was examined using an in-vitro system. Femur-[autograft MCL]-tibia complexes were subjected to a tensile stress of 4 MPa at 0.5 Hz for 1 min, followed by 14 min of rest. This 15-min testing cycle was repeated for 4 h. Semi-quantitative reverse transcrip-tase polymerase chain reaction (RT-PCR) was performed on RNA from mechanically treated MCL autografts, using rabbit-specific primer sets for types I and III collagen, biglycan, decorin, fibromodulin, lumican, versican, matrix metalloproteinase-1 (MMP-1, collagenase-1), MMP-13 (collagenase-3), and a housekeeping gene, glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Interestingly, 4 h of culture of normal control MCLs led to increased mRNA levels for MMP-1 (P < 0.05), but there were no significant changes in MMP-13 mRNA levels. Total RNA levels in that normal MCL tissue were, however, decreased after culture (P < 0.05). In-vitro tensile loading of in-vivo mobilized autografts resulted in a significant increase in total RNA (185% of in-vitro non-loaded autografts). On the other hand, in-vitro tensile loading of in-vivo immobilized autografts resulted in no significant changes in total RNA levels compared with levels in non-loaded control grafts. MMP-1 mRNA levels in both the in-vivo mobilized (47% of non-loaded autograft) and in-vivo immobilized (38% of non-loaded autograft) MCL autografts were significantly lower than those in non-loaded control tissue following in-vitro tensile loading, but there were no significant changes in the mRNA levels for the seven other matrix molecules assessed. These results show that it is possible to selectively inhibit MMP-1 mRNA levels in autograft ligaments by supplying mechanical stimuli in vitro. The results also demonstrate that in-vivo immobilization leads to a decrease in the effects of subsequent in-vitro mechanical loading in such autografts with respect to total RNA levels. Collectively, these results demonstrate that both in-vivo and in-vitro loading have implications in the engineering of an ideal ligament graft.
...
PMID:In-vitro cyclic tensile loading of an immobilized and mobilized ligament autograft selectively inhibits mRNA levels for collagenase (MMP-1). 1118 Sep 9


1 2 3 Next >>

---