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)

Oral administration to mice with soybean trypsin inhibitor (SBTI) (27-30 mg/mouse/day) or aprotinin (5500-6000 KIU/mouse/day) for six weeks increased the total pancreatic insulin (IRI). The pancreatic IRI was also increased after sc injections of synthetic caerulein (0.05 microgram/mouse/day divided into 3 daily doses), being 82% above the control levels when expressed per g pancreas. Aprotinin (6000 KIU/mouse/day divided into 3 daily doses) injected sc had no effect on the insulin content. The total glucagon did not change significantly in any of the groups, but the molar ratio of insulin to glucagon was increased in the caerulein- and SBTI-treated mice. Caerulein-treatment led to an increased disappearance rate of glucose with k-values being 7.1 +/- 0.3 compared to 6.0 +/- 0.1 (mean +/- SEM) in the controls (P less than 0.02). In islets isolated by collagenase-digestion of the pancreas and subjected to an overnight incubation, the content of insulin and glucagon was increased in islets from caerulein-treated animals. This corresponded to the results observed in the whole pancreas. The present study suggests that oral administration of proteolytic enzyme inhibitors or treatment with caerulein has a trophic effect on the endocrine pancreas. A difference in specificity seems to exist as SBTI affected both the pancreatic weight and IRI, and aprotinin orally did not influence the pancreatic weight, but increased the total content of IRI. Caerulein led to an increase in IRI, but did not affect the weight of pancreas.
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PMID:Effects of caerulein and trypsin inhibitors on the endocrine mouse pancreas. 616 52

In an attempt to justify use of trypsin to achieve more thorough dispersion of luteal cell clumps in vitro, progesterone (P) production by collagenase dispersed monkey luteal cells from the mid-luteal phase corpus luteum (CL) was examined in vitro either after 10 min, or continuous (3h) exposure to trypsin (TR). In the first experiment, cells were pre-incubated in TR, then incubated at 37 degrees C for 3h with human chorionic gonadotropin (hCG) after the addition of soybean-trypsin inhibitor (STI). Pre-incubation of luteal cells with TR had no effect on the level of P production under basal conditions. Cells that were preincubated with TR responded to hCG stimulation with increased progesterone secretion (P less than 0.01) in a fashion similar to untreated cells. P production in response to hCG was independent of TR concentration over the range of 0.05% to 0.2% during the pre-incubation period. However, continuous exposure (3h) of cells to TR significantly depressed (P less than 0.01) basal P secretion and inhibited the response to hCG. We conclude that TR had no effect on the biopotency of hCG per se, but probably the over-exposure to TR had an adverse effect on the LH/hCG receptors. Addition of STI after a 10 min pre-incubation with TR, prevented these deliterious effects, thereby permitting the use of TR to improve the completeness of luteal cell dissociation.
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PMID:Progesterone production by dispersed monkey (Macaca mulatta) luteal cells after exposure to trypsin. 624 60

A neutral extract from human leukocytes was shown to have proteolytic activity which could degrade triple-helical basement membrane collagen from bovine lens capsules into specific triple-helical sub-fragments. The enzymes responsible is not identical to the leukocyte collagenase active against interstitial collagen types I, II and III. After denaturation, the neutral protease reaction products showed three major peptides with molecular weights of 70,000, 50,000 and 30,000, by dodecylsulphate gel electrophoresis analysis. Electron microscopic observation and viscosity measurements showed the initial twice-pepsinized collagen to be comprised of intact rod-like molecules about 300 nm long. The fragments produced by the protease were also triple-helical and were resistant to the action of trypsin at 20 degrees C. The fragments were completely degraded by purified bacterial collagenase or by raising the reaction temperature above the melting temperature of the basement membrane collagen during incubation with leukocyte extract. Enzyme activity has its pH optimum between 7 and 9, EDTA, EGTA and 1,10-phenanthroline (metal-chelating agents) completely inhibited enzyme activity, as did serum. Partial inhibition of the activity was obtained with phenylmethylsulfonyl fluoride and soybean trypsin inhibitor.
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PMID:Degradation of basement-membrane collagen by neutral proteases from human leukocytes. 624 53

A neutral protease has been extracted from the media of cultured metastatic tumor cells and purified approximately 1000 times after sequential ammonium sulfate fractionization, concanavalin A column chromatography, and molecular sieve chromatography. The protease has an apparent molecular weight of 70 000--80 000, is inactive at acid pH, requires trypsin activation, and is inhibited by ethylene-diaminetetraacetic acid but not by phenylmethanesulfonyl fluoride, N-ethylmaleimide, or soybean trypsin inhibitor. The enzyme produces specific cleavage products for both chains of pro type IV collagen isolated without pepsinization and apparently cleaves at one point in a major pepsin-extracted chain of placenta type IV collagen. The partially purified enzyme fails to significantly degrade other collagens or fibronectin under digestion conditions in which specific reaction products are produced for type IV collagen. The existence of this enzyme is significant since previously described animal collagenases fail to degrade type IV collagen. Such a type IV specific collagenase could play a role in tumor invasion and may be secreted by other cells such as endothelial cells, epithelial cells, and immune cells.
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PMID:Partial purification and characterization of a neutral protease which cleaves type IV collagen. 625 30

Latent pig synovial collagenase (EC 3.4.24.7) can be activated by a variety of different treatments to give an active enzyme form of lower molecular weight which rapidly degrades collagen. Trypsin and plasmin effectively activated the latent collagenase whilst elastase and cathepsin G degraded most of the latent enzyme before it was activated. A number of mercurials were compared and maximum activation was achieved using 4-aminophenylmercuric acetate and phenylmercuric chloride. The latent collagenase bound to a mercurial-Sepharose column and was eluted in the active form with NaCl. The latent collagenase also activated spontaneously and the conditions which encouraged and prevented this activation were studied. High NaCl concentration, diisopropylphosphofluoridate, soybean trypsin inhibitor, low Zn2+ concentration and high and low pH all prevented the spontaneous activation of latent pig synovial collagenase.
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PMID:The activation of latent pig synovial collagenase. 626 Feb

The present work was designed to investigate the capacity of trophozoites of Entamoeba histolytica to adhere to and digest human collagen types I and III in vitro. The time-course of binding of ameba to both human collagen types I and III was similar. However, the kinetics of detachment were different for each collagen type. Trophozoites of E. histolytica cultured on heat-reconstituted type I collagen gels produced a well-defined area of lysis. Quantitative studies using 14C-labeled collagen revealed that after 24 h of incubation, Entamoeba digested three and a half times more type I than type III collagen, thus suggesting the presence of a collagenase with higher specificity for type I collagen. This activity was optimum with trophozoites harvested after 42 h in culture (1.5 X 10(5) trophozoites/ml). The digestion of type I collagen was a function of the number of trophozoites, and was inhibited by EDTA, L-cysteine, and serum, but not by soybean trypsin inhibitor, phenylmethanesulfonyl fluoride, or N-ethylmaleimide (NEM). Electrophoretic analysis of the type I collagen fragments revealed three main classes of polypeptides of 75,000, 50,000, and 25,000 daltons. Subsequent proteolysis of these collagen fragments was probably carried out by other proteases derived from trophozoites. This activity was inhibited with 10 mM NEM. Collagenase activity appeared to be located at the plasma membrane and direct contact of the ameba with the substrate is required for collagen digestion. The results suggest that collagenase activity of E. histolytica may play an important role in tissue invasion.
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PMID:The collagenase of Entamoeba histolytica. 627 95

Rheumatoid synovial fluid contains an activator of latent collagenase from culture medium of pig synovium. The activator was purified by gel chromatography on Ultrogel AcA 44 and affinity chromatography on soybean trypsin inhibitor coupled to Sepharose 4B. The purified material was homogeneous on SDS-polyacrylamide gel electrophoresis with Mr 88 000. The activator had limited proteolytic activity against azo-casein, but showed amidase activity on Pro-Phe-Arg-NMec, Z-Phe-Arg-NMec, D-Val-Leu-Arg-NPhNO2 and D-Pro-Phe-Arg-NPhNO2, with an optimum at pH 8.0. Activity was completely inhibited by diisopropyl fluorophosphate, soybean trypsin inhibitor, leupeptin and Pro-Phe-Arg-CH2Cl, whereas lima bean trypsin inhibitor, Tos-Lys-CH2Cl, a specific inhibitor of factor XIIa from maize, EDTA and iodoacetate were not inhibitory. These properties of the activator suggested that it might be plasma kallikrein (EC 3.4.21.34), and the possibility was further examined. The activator was treated with [3H]diisopropyl fluorophosphate, and run in SDS-polyacrylamide gel electrophoresis with reduction; a radioautograph of the gel showed a pair of [3H]diisopropyl phosphoryl-labelled bands (Mr 36 000 and 34 000) identical to those obtained with authentic plasma kallikrein. Double immunodiffusion with monospecific antiserum against human plasma kallikrein confirmed the identification. This is the first demonstration of collagenase-activating activity of plasma kallikrein, and raises the possibility that activation of prokallikrein in the inflamed joint space may contribute to the disease process not only by the production of bradykinin, but also by activating latent collagenase.
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PMID:Identification of plasma kallikrein as an activator of latent collagenase in rheumatoid synovial fluid. 627 61

The finding that incubation of rat adrenal capsules (largely zona glomerulosa) with trypsin reproducibly releases aldosterone and 18-hydroxycorticosterone (18-OH-B) from tightly protein-bound tissue stores leads to the hypothesis that the secretion of these steroids may be under the control of endogenous proteases. Rat adrenal capsule whole tissue and collagenase-dispersed cells were incubated under conditions of stimulation by (1-24)ACTH (10(-7) mol/l), potassium (8.4 X 10(-3) mol/l) or dibutyryl cyclic AMP (dbcAMP) (10(-4) mol/l) with the addition in some flasks of one of the following protease inhibitors at the appropriate concentration for their known actions: N alpha-p-tosyl-L-arginine methyl ester (TAME; 10(-2) mol/l), 2-nitro-4-carboxyphenyl-N,N'-diphenylcarbamate (NCDC; 2 X 10(-6) mol/l), N alpha-benzoyl-L-arginine (BA; 10(-2) mol/l), p-nitrophenyl-N alpha-benzyloxycarbonyl-L-lysinate (CBZ-NL; 2 X 10(-6) mol/l) and soybean trypsin inhibitor (STI; 1 mg/ml). The (1-24)ACTH-stimulated steroid output in dispersed cells was not affected by NCDC, BA or CBZ-NL. However, all of the inhibitors except STI produced selective effects on aldosterone and 18-OH-B production by whole capsule tissue under certain conditions. Thus TAME and NCDC significantly inhibited the dbcAMP-stimulated production of these two steroids (aldosterone values decreased from 328 +/- 35 to 128 +/- 15 and 157 +/- 32 ng/gland pair respectively) and furthermore NCDC elicited the same effect in potassium- or ACTH-stimulated whole tissue (e.g. in K+-stimulated tissue aldosterone decreased from 79 +/- 15 to 40 +/- 7 ng/gland pair). The reverse effect was shown by BA and CBZ-NL in potassium-stimulated whole tissue, and yields of aldosterone and 18-OH-B were significantly enhanced (aldosterone increased from 79 +/- 15 ng/pair to 151 +/- 14 ng in the presence of BA). The high molecular weight inhibitor STI had no effect on potassium-stimulated whole tissue, but enhanced the yield of extractable aldosterone from 9.7 +/- 1.7 to 16.9 +/- 2.3 ng/pair when added to incubations of a cytosol preparation. The results suggest that endogenous proteases in rat adrenal whole capsule tissue play specific roles in the control of aldosterone and 18-OH-B secretion. Some (type 1) whose action is mimicked by trypsin, are inhibited by TAME and NCDC and appear to be involved in the release of these two steroids from their tight (apparently covalent) binding to protein.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Serine proteases selectively control the output of 18-hydroxycorticosterone and aldosterone in stimulated zona glomerulosa tissue of the rat adrenal. 631 38

A method for the isolation of single smooth muscle cells from guinea pig taenia caeci is described. The single cells were prepared by digestion with 0.3% collagenase and 0.6% trypsin inhibitor in Ca2+-free solution. This procedure produced a high yield of intact cells. Most cells obtained by this procedure were relaxed and showed large contractile responses to excitatory stimulus. Maximal responses of the single cells to acetylcholine (ACh), histamine, and high K+ were attained within 20 sec, and the per cent decrease in cell length was 30-40%. Times for maximal responses of the single cells were shorter than those of the muscle strips. Single cells exhibited a dose-dependent graded response to calcium under depolarized conditions, ACh, histamine, and high K+, and a voltage- and duration-dependent response to electrical stimulation. The ED50s of ACh in the single cells and in the muscle strips were about 2 X 10(-8) and 1.5 X 10(-7) M, respectively. The muscle strips had a lower sensitivity than the single cells to ACh. The generally smooth surface of the relaxed cell contrasted with the numerous evaginations present on the fully contracted cell. I believe that single smooth muscle cells isolated from guinea pig using my technique are, at present, better for physiological and pharmacological studies than are cells isolated using other techniques.
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PMID:Isolation and contractile properties of single smooth muscle cells from guinea pig taenia caeci. 632 80

A technique is described to detect the activity of protease inhibitors present in sodium dodecyl sulfate (SDS)-polyacrylamide gels (PAG) containing a copolymerized enzyme substrate. The method involved (1) incorporation of substrate (gelatin or casein) into the SDS-PAG at the time of casting; (2) electrophoresis of the protease inhibitors in the presence of SDS; (3) removal of SDS by washing the gel in 2.5% (w/v) Triton X-100; (4) incubation of the gels in a solution containing the proteolytic enzyme at 37 degrees C for 16 h; and (5) staining undigested substrate with amido black. Standard inhibitors such as bovine pancreatic trypsin inhibitor (BPTI), soybean trypsin inhibitor (SBTI), alpha 1-antitrypsin inhibitor, and a protease inhibitor derived from human articular cartilage have been examined by this method and displayed sharp inhibition bands when the gels were treated with bovine trypsin, chymotrypsin, or other enzymes. The technique cannot be used for precise quantification of protease inhibitors. However, there is a relationship between the concentration of inhibitor used and the intensity of staining. By this means, it was possible to estimate the smallest amount of inhibitor that could be detected (against a particular enzyme) under a given set of conditions. Inhibition was detected when 10 ng of SBTI or 20 ng of BPTI were applied to the gels; human alpha 1-protease inhibitor could be detected at a level of 2-3 micrograms. The technique was used to investigate the effectiveness of the human cartilage inhibitor against a variety of proteolytic enzymes, including thermolysin, Pronase, neutral protease, elastase, protease VII, pepsin, bacterial collagenase, protease IV, and papain.
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PMID:Detection of protease inhibitors using substrate-containing sodium dodecyl sulfate-polyacrylamide gel electrophoresis. 635 99


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