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

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

The authors present morphological characteristics of primary monolayer cultures prepared from the pancreas of bovine fetuses. Combined treatment with trypsin and collalytine solutions (a preparation with collagenase activity) was used for dispersion of the tissue of the pancreas. Numerous epithelial cells corresponding by morphofunctional characteristics to beta-cells of the islets of Langerhans were contained in be cultures obtained; an aldehyde-fuchsin-positive granularity was revealed in the cytoplasm of these cells. Degranulation of these cells occurred under the effect of an increased glucose concentration in the nutrient medium.
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PMID:[Cell cultures obtained using collalytin from the pancreases of cattle fetuses]. 19 89

In the present work, homogeneous isolated pancreatic islet-cells were transplanted to diabetic rats with the aim of verifying if the transplanted tissue could survive and reduce the plasma glucose concentration on the alloxan-induced diabetic receptors. For the isolation of the pancreatic islets, pancreas was incubated in collagenase solution for about 13 +/- 3 minutes, followed by centrifugation in Ficoll gradients. The islets, 3 000 to 5 000, were transplanted to alloxan diabetic recipients, in a territory, preferentially with portal-hepatic drainage (mesentery and spleen). Sixty per cent of the recipients exhibited a fall of the plasma glucose concentration, up to 70%, while in the control animals, the diabetes persisted. The islets were found in the recipients mesentery up to 10 days after transplantation, and all of them showed heavily granulated (aldehyde fuchsin positive) beta cells. After this time, islets were not found. These results indicate that islets can survive and attenuate diabetes in alloxan-treated rats, and that, probably, the number of islets transplanted as well as the receiving areas play an important role.
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PMID:Transplantation of islets of Langerhans in diabetic rats. 35 20

An electron histochemical study was carried out on bone nodules formed in vitro in collagenase-released calvarial cells in order to visualize the lipid components of the extracellular matrix (EM). The malachite green aldehyde fixative technique, which allows both preservation and staining of some phospholipids of the extracellular matrix, was used. Controls were performed on sections demineralized, and then submitted to lipid extraction with a chloroformmethanol mixture (2/1 v/v) and to glycosaminoglycans digestion with 0.5% bovine testicular hyaluronidase to verify specificity for lipid staining. This allowed us to visualize the lipids (1) in the osteoid as granules associated to ribbon-like structures connected to the collagen fibers, (2) as electrondense deposits seen as dots on the outer surface membrane of the matrix vesicles, and (3) in the mineralized matrix as roundish patches formed of needle-shaped materials and at the mineralization front as individual ones. This study demonstrated that at the EM level, the lipids are present in the osteoid at locations very similar to what have been observed for the glycosaminoglycans, and in the mineralized matrix as components of the crystal ghosts.
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PMID:Localization of malachite green positive lipids in the matrix of bone nodule formed in vitro. 161 3

In addition to fibrosis in response to necrosis and inflammation, alcohol may promote fibrogenesis directly, resulting in pericellular, perisinusoidal and perivenular fibrosis, in association with increased collagen mRNA. Acetaldehyde (produced in increased amounts because of the selective induction of cytochrome P450IIE1) stimulates collagen formation from either myofibroblasts, Ito cells or fibroblasts. One postulated mechanism is adduct formation of acetaldehyde with intracellular proteins, possibly stabilized by the NADH generated upon ethanol oxidation. The latter also increases lactate which might inhibit proline oxidase activity and increase available proline. During the initial stage of alcohol consumption, collagenase activity is increased, in keeping with enhanced collagen production. In later stages, however, there is a secondary decrease of collagenase activity; its deficiency relative to synthesis may also promote collagen deposition. In the early stage of alcohol induced fibrosis, collagens type I and type III accumulate, whereas later, type I predominates. Both can be formed in vitro by Ito cells, but cultured hepatocytes produce mainly type III. Immunohistochemical techniques revealed the deposition of type III procollagen in the extrahepatic collagen fibrils. Its degradation, as well as its enhanced synthesis, contribute to the appearance of procollagen III peptides in the blood. Their measurement by Fab fragments of the antibody is useful to assess the degree of fibrosis and to detect perivenular fibrosis, a precirrhotic lesion. In the baboon model, polyunsaturated lecithin was found to be effective in opposing alcohol-induced fibrosis.
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PMID:Alcohol and fibrogenesis. 184 59

We tested the effect of ethanol and its metabolite, acetaldehyde, on bone formation as measured by [3H]proline incorporation into collagenase digestible protein (CDP) and noncollagen protein (NCP), and on DNA synthesis as measured by [3H]thymidine (TdR) incorporation in fetal rat calvaria. We also determined the effects of ethanol and acetaldehyde on prostaglandin E2 (PGE2) release from calvaria and on bone resorption as measured by 45Ca release from fetal rat long bones. Bones were cultured in multiwell plastic dishes (open system) or in stoppered Erlenmeyer flasks (closed system) for 24 to 96 h. In the open system, 1% ethanol (v/v; 172 mM) resulted in a 31% decrease in TdR incorporation at 24 h with no effect on CDP and NCP. At 0.1% (17.2 mM), ethanol increased TdR by 22%, CDP by 73% and NCP by 67% at 24 h, but these effects were not sustained at 96 h. At 24 h, 1% and 0.3% ethanol decreased PGE2 release by 88% and 75% respectively. This effect was sustained for 96 h only at the higher concentration. In the closed system, 0.1% ethanol increased TdR incorporation by 38% at 24 h. However, there was no effect on the labeling of CDP or NCP. Because its boiling point is 21 degrees C, acetaldehyde could only be tested in the closed system. Acetaldehyde markedly inhibited bone metabolism. At 24 h, 0.003% (0.54 mM) to 0.01% (1.79 mM) acetaldehyde caused a dose-related inhibition of TdR incorporation from 23 to 45%. At 0.01% and 0.03% acetaldehyde inhibited proline incorporation into CDP by 48% and 94% and NCP by 40% and 74% respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of ethanol and acetaldehyde on collagen synthesis, prostaglandin release and resorption of fetal rat bone in organ culture. 233 31

A direct Schiff reaction of elastic tissues has been known for many years, but the nature of the native aldehyde-rich components has not been clear. In this study, chicken, quail, and rat embryos and adult rat lung, aorta, and kidney were fixed in methacarn or in a formalin solution, embedded in paraffin, and sections of 8-10 micron obtained. Rehydrated sections were incubated for various periods in solutions of the enzymes chondroitinase ABC, clostripain, collagenase, elastase, heparatinase, hyaluronidase, subtilisin Carlsberg ("protease"), or trypsin, and in solutions of phosphomolybdic acid or sodium borohydride. After incubation, sections were placed, without prior oxidation, in Schiff's reagent, and were ultimately observed and photographed in transmitted light or with blue or green epifluorescence. A Schiff-positive substance was found, always and exclusively, in elastic tissues of the vasculature and lungs, which was hydrolyzed by the proteolytic enzymes to an extent that ranged from complete loss of Schiff reaction in minutes (trypsin) to no loss of Schiff reaction in 22 hr (clostripain). The Schiff-reactive protein preceded the time of appearance of elastin in the early embryos. We conclude that the aldehyde-rich protein responsible for this reaction is a harbinger of elastogenesis in vivo and speculate that it may represent the elastic microfibril or a component thereof.
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PMID:A new interpretation of the direct Schiff reaction of elastic connective tissue. 244 56

Rat uterine tissue was dissociated by enzymatic digestion with collagenase and viable mast cells were obtained. Their viability was assessed by the ability to exclude trypan blue dye and to respond functionally to different stimuli. Challenge with anti-IgE gave a calcium-dependent histamine release of 49%, whilst the undigested uterine fragments gave 23%. Moreover, they were capable of releasing histamine on challenge with the compound 48/80, suggesting a similarity with connective tissue mast cells. This similarity was further supported by their insensitivity to aldehyde blocking of dye binding. The final dispersed cell preparation contained 3 X 10(5) mast cells/g of uterine tissue, representing about 2% of total nucleated cells. The total histamine content of the undigested uterus was 2.5 micrograms/g of tissue, whilst after digestion the histamine determined was 1.2 pg per mast cell with a yield of 14%. The total histamine content of the uterus changed throughout the reproductive cycle, increasing before ovulation, reaching a maximum during ovulation and then decreasing after embryo implantation. This suggests that the implanting embryo, interacting with the uterus, may be capable of inducing the release of histamine. The embryo-derived histamine releasing factor (EHRF) that we have described previously is capable of inducing 22% histamine-release on uterine mast cells, thus supporting this hypothesis.
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PMID:Dispersal of rat uterine mast cells and their functional response to an embryo-derived histamine releasing factor: a possible model for embryo implantation. 246 97

Proteolytic destruction of pig aortal valves was studied at various steps of their preparation to implantation (native tissue, the tissue treated with terrylytine as well as with terrylytine and glutaric aldehyde) using pig pancreatic elastase and bacterial collagenase. The rate of the tissue destruction was estimated by means of monitoring an increase in content of protein and amino nitrogen in the hydrolysates. The tissue treated with terrylytine and glutaricaldehyde was 10-40-fold more resistant to proteolysis as compared with native heart valve tissue. Inadequate stabilizing effect of glutaric aldehyde on elastin, as compared with that on collagen, was found, when proteolysis of native and modified with glutaric aldehyde elastin from bovine cervical ligament and of calf skin collagen was studied using elastase and collagenase, respectively.
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PMID:[Resistance of heart valve bioprosthesis to the proteolytic effect of collagenase and elastase]. 256 Aug 68

The collagenase from Clostridium histolyticum is a mixture of several collagenases, all of which are zinc metalloproteases. This enzyme catalyzes the cleavage of the X-Gly peptide bond in the repeating sequence of collagen: -Gly-Pro-X-Gly-Pro-X-. Thus the S3, S2, and S1 subsites on the enzyme appear to be occupied by the sequence -Gly-Pro-X- and the S1', S2', and S3' subsites also by -Gly-Pro-X-. Short peptides up to and including N alpha-acyltetrapeptides containing the repeat sequence do not detectably inhibit the enzyme (IC50 greater than 10 mM). However, peptide aldehydes of the form aminoacyl-X-glycinal, presumably occupying the S1, S2, ..., Sn subsites, are inhibitors. The most potent of these was Pro6-Gly-Pro-glycinal, with an IC50 of 340 +/- 70 microM. The single peptide aldehyde investigated, which could occupy the S1' and S2' subsites, 4-oxobutanoyl-L-proline, did not inhibit collagenase (IC50 greater than 20 mM). The peptide ketone 5-benzamido-4-oxo-6-phenylhexanoyl-Pro-Ala (XXV), which could occupy the S1-S3' subsites, inhibits collagenase with an IC50 of 120 +/- 50 microM, over 80-fold more potently than its parent peptide analogue benzoyl-Phe-Gly-Pro-Ala (XXIII). The alcohol analogue of XXV, 5-benzamido-4-hydroxy-6-phenylhexanoyl-Pro-Ala (XXVI), is over 60-fold less potent with an IC50 of 8 +/- 2mM. Extending the peptide ketone XXV to occupy the S2-S3' subsites gave 5-(N alpha-carbobenzoxy-L-prolinamido)-4-oxo-6-phenylhexanoyl-Pro -Ala (XXVII). Surprisingly, XXVII had an IC50 of only 5.2 +/- 2 mM.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Aldehyde and ketone substrate analogues inhibit the collagenase of Clostridium histolyticum. 300 33

A number of peptide hydroxamic acids have been synthesized and have been shown to be inhibitors of human skin collagenase. One of these, Z-Pro-Leu-Gly-NHOH, has an IC50 value of 4 X 10(-5)M. Corresponding peptides with different C-terminal functional groups, such as amide, carboxylate and aldehyde, showed little or no inhibition, indicating the importance of the hydroxamate functional group. In addition, the peptide sequence of this effective inhibitor corresponds closely to that of the cleavage site of native collagen, the substrate for the enzyme. Thus, substrate analogs incorporating a suitable metal coordinating group serve as potential inhibitors of human collagenase.
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PMID:Peptide hydroxamic acids inhibit skin collagenase. 301 Sep 73


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