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)

Ten isolates of Haemophilus ducreyi, including seven clinical isolates and three laboratory reference strains, were assessed for their ability to produce extracellular enzymes which might contribute to their pathogenicity. Protease, elastase, lecithinase, lipase or collagenase enzyme activity were not detected in culture filtrates from any of the isolates tested using either plate or spectrophotometrical assays. Furthermore, cell-free culture filtrates did not exhibit cytotoxic activity in vitro when tested using either an established tissue culture cell line (Vero) or a primary cell culture of human keratinocytes. These results suggest that extracellular products do not play a role in host invasion or production of tissue damage by H. ducreyi.
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PMID:Absence of extracellular enzyme activity and cytotoxicity in cell-free culture filtrates of Haemophilus ducreyi. 166 61

Effect of cholinergic stimulation on the release of digestive enzymes from isolated rat pancreatic acini prepared by collagenase digestion was investigated. The release of enzymes (amylase, chymotrypsinogen, lipase) increased linearly with the time of incubation in the absence of secretagogues. Carbachol, a muscarinic agonist, induced a remarkable increase in the release of these enzymes. This carbachol-stimulated amylase release showed a biphasic curve, and its maximal response was observed at 10(-5) M. The release patterns of chymotrypsinogen and lipase were similar to that of amylase. This carbachol-stimulated amylase release was inhibited by atropine in a dose-dependent manner, with an ED50 value of 1.17 X 10(-8) M. Other cholinergic agonists such as methacholine also stimulated the release of these enzymes, and these increases in the release were inhibited by atropine. Scatchard analysis for [3H]quinuclidinyl benzilate ([3H]QNB) binding to isolated pancreatic acini revealed that the binding site of [3H]QNB was a single component with a Kd value of 0.09 nM and a Bmax value of 89.3 fmol/mg protein, respectively. The effect of other cholinergic antagonists, pirenzepine and AF-DX 116 (11-[[2-[(diethylamino) methyl]1-piperidinyl]acetyl]-5,11-dihydro- 6H-pyrido[2,3-b][1,4]-benzodiazepine-6-one), on pancreatic acini was also investigated. Based on these results, it has been concluded that isolated rat pancreatic acini have muscarinic receptors and are useful for analyzing the mechanism of pancreatic enzyme secretion.
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PMID:Release of digestive enzymes from isolated rat pancreatic acini following muscarinic stimulation: a comparative study with enzyme release and receptor binding. 171 8

Release of macromolecules by S. digitata, in 9 different media under in vitro condition have been studied. A direct relationship between microfilariae (mf) release and associated folin positive materials was seen in majority of the cases. High activities of hydrolytic enzymes such as protease, collagenase, alkaline phosphatase and lipase were detected in the excretary-secretary products and worm preparations. Activity of collagenase could not be detected in the male worm under experimental conditions.
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PMID:In vitro release of biologically active materials from the bovine filarial parasite Setaria digitata. 181 83

Sixteen clinical isolates comprising six each of type A and type B of Hendersonula toruloidea, three of Scytalidium hyalinum and one of S. japonicum were investigated for their physiological characteristics. All the isolates utilized 13 carbon sources and three nitrogen sources tested and grew in a medium containing 3.7 M NaCl. A concentration of 4.5 M NaCl inhibited the growth of all the isolates. The isolates produced amylase, lipase and protease but failed to produce collagenase.
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PMID:Physiological characteristics of clinical isolates of Hendersonula toruloidea and Scytalidium species. 182 May 14

Production of 9 enzymatic activities of 527 strains freshly isolated from periodontal pockets in advancing periodontitis were investigated. Of these isolates, two strains showed lecithinase activity on egg yolk agar plate. Collagenase, plasmin and lipase were produced by 28 strains, 26 strains and 22 strains, respectively. Two lecithinase-producing strains were identified as Bacteroides intermedius. Nineteen strains of B. intermedius and 1 strain of Fusobacterium species produced lipase on egg yolk agar plate. All of the 28 collagenase-producing strains were B. gingivalis. B. gingivalis (20 strains) and non black-pigmented Bacteroides (6 strains) showed plasmin activity. These results indicate that Bacteroides species, mainly B. gingivalis and B. intermedius may exert an important influence on the exacerbation of the disease.
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PMID:[Distribution of enzymatically pathogenic bacteria from periodontal pocket in advancing periodontitis]. 196 47

Nutritional factors, especially the protein and fat content of the diet, may alter the likelihood of pancreatic injury after a number of insults, including chronic ethanol intake. This issue was studied experimentally by match-feeding rats liquid diets of varying protein content with and without ethanol. Protein synthesis and enzyme secretion were investigated, because these parameters are believed to increase the capacity for pancreatic autodigestion. Protein synthesis was assessed by determining the incorporation of tritiated phenylalanine into trichloroacetic acid precipitated protein 10 minutes after IP injection and then corrected for the size of the precursor pool. Enzyme secretion was studied using pancreatic acini, which were prepared using clostripain-poor collagenase. Chronic ethanol feeding stimulated protein synthesis and lipase secretion and content in rats receiving adequate amounts of protein. These stimulatory effects of ethanol were markedly attenuated in rats administered protein poor diets. Protein deficiency per se significantly decreased the weight, protein, and enzyme content of the rat pancreas as well as increased the percentage release of lipase from acini. Although extrapolation from animal studies may be tenuous, the present findings may explain the link between nutrition and the occurrence of alcoholic pancreatitis.
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PMID:Interactive effects of dietary protein and ethanol on rat pancreas. Protein synthesis and enzyme secretion. 198 46

We wished to determine whether the stimulation of protein synthesis by CCK8, carbachol, and insulin in isolated rat pancreatic acini resulted from translational or transcriptional induction of protein synthesis, and whether these hormones had similar or different effects on the rates of synthesis of individual enzymes. Isolated pancreatic acini were prepared from streptozocin-treated rats by collagenase digestion, mechanical dissociation, and centrifugation through a bovine serum albumin (BSA) cushion. Sixty-minute incubations, with maximally effective doses of CCK8, carbachol, and insulin, produced a 50, 90, and 100% increase, respectively, in the rate of protein synthesis. After inhibition of transcription with actinomycin D, the hormones still produced a 23, 50, and 61% increase, respectively, in the rate of protein synthesis. The study of the effect of the three hormones and the combination of CCK8 and insulin on the rate of synthesis of trypsinogen, chymotrypsinogen, lipase, and amylase, purified by isoelectric focusing, demonstrated that the hormones induced similar effects on the pattern of enzyme synthesis, and that they all induced the rate of synthesis of chymotrypsinogen slightly more than that of the other enzymes studied. We conclude that the hormones studied exert similar posttranscriptional influences in the regulation of protein synthesis in the pancreatic acinar cell.
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PMID:Translational control of protein synthesis in isolated pancreatic acini: role of CCK8, carbachol, and insulin. 243 15

A simple and inexpensive procedure is described which allows reproducibly the isolation of rat pancreatic acinar cells. Using only small quantities of commercially available collagenase without addition of any further protease, a cell population consisting of about 95% of acinar cells can be obtained within about 95 min. Cell yield is 40% as calculated on a dry weight basis. Enzyme activities measured within final suspensions of isolated cells are: amylase, 1.17 +/- 0.27 amylase units.(mg d.w.)-1; lipase, 23.78 +/- 6.02 nkat.(mg d.w.)-1 and alanine aminotransferase, 0.895 +/- 0.236 nkat.(mg d.w.)-1. Isolated cells are morphologically intact as seen by electron microscopy and retain their viability for more than 3 h, even when incubated at 37 degrees C without any substrate and protease inhibitor, as revealed by their ability to exclude trypen blue. Therefore, acinar cells isolated in this manner may prove useful for investigations at cellular level into pathogenetic mechanisms underlying pancreatic diseases.
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PMID:An optimized procedure for isolation of rat pancreatic acinar cells. 246 96

To identify microanatomic and chemical features that may mark the transition from asymptomatic to symptomatic atherosclerotic carotid lesions, we evaluated 62 carotid artery bifurcation plaques including 45 high-grade stenoses removed at endarterectomy and 17 nonstenotic plaques recovered at autopsy. Morphologic features were evaluated on multiple-interval histologic sections and were graded for the presence of hemorrhage, ulceration, thrombosis, lumen surface irregularity, and calcification. Plaque hemorrhage, recent and remote, was found in most of the specimens, and did not discriminate between symptomatic and asymptomatic stenotic plaques. High-grade carotid stenotic plaques were associated with a significantly higher incidence of ulceration (53%), thrombosis (49%), and lumen irregularity (78%) when compared to nonstenotic asymptomatic plaques (6%, 0%, and 17%, respectively; p less than 0.01). Although these features were more prominent in lesions that produced symptoms, they were present in 80% of the stenotic bifurcations, and did not distinguish between symptomatic and asymptomatic endarterectomy plaques. No significant differences were found between symptomatic and asymptomatic high-grade lesions with respect to collagen, DNA, total cholesterol, fibrinogen, lipase, elastase, or collagenase content. We conclude that intraplaque hemorrhage is commonly seen in carotid plaques even without severe stenosis, and it does not appear to be a dominant determinant of symptoms. Ulceration and surface thrombi that may lead to cerebral embolization are prominent features in markedly stenotic plaques even when symptoms are absent. The disruptive processes that underlie plaque instability appear to be closely associated with plaque size and stenosis rather than plaque composition.
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PMID:Critical carotid stenoses: morphologic and chemical similarity between symptomatic and asymptomatic plaques. 253 32

Intrapancreatic activation of proteases is believed to play a major role in the pathogenesis of acute necrotizing pancreatitis. Several authors have questioned, however, the central role of trypsin in autodigestion of the pancreas. To clarify the direct effects of pancreatic enzymes and other related factors on acinar cells, we used the model of isolated pancreatic acini. Acini were prepared from male Wistar rats by collagenase digestion. Protein synthesis was measured by incubation of acini with [35S]methionine. Acini were resuspended thereafter in fresh buffer and further incubated for 30-90 min under various conditions [e.g., with pancreatic homogenates, ascites (from rats with pancreatitis induced by sodium taurocholate), pure pancreatic enzymes, and other factors]. The percentage of release of newly synthesized proteins into the culture medium was regarded as a biochemical parameter of cellular integrity. A morphologic score of cellular integrity was obtained via light microscopic evaluation of acini at the end of the various incubations by measuring the degree of cell lysis, loss of cell granules, ballooning, formation of vacuoles, and karyopyknosis. When normal [35S]methionine-labeled pancreatic acini were incubated with various factors, the percentage of release of labeled proteins into the medium was as follows: incubation with HEPES/Ringer's buffer, 1.8%; hemorrhagic pancreatic ascites, 3.8%; pancreatic homogenates, 2.0%; lipase, 1.8%; phospholipase A2, 3.0%; phospholipase A2 + lecithin, 3.2%; trypsin, 2.5%; 5% olive oil, 1.8%; ascites + olive oil, 78.3%; ascites + homogenized epididymal fat, 79.9%; lipase + olive oil, 32.0%; pancreatic homogenates + olive oil, 28.0%; diolein, 2.65%; and oleic acid, 62.9%. The cellular release of radiolabeled proteins showed an inverse correlation with cellular integrity as shown by light microscopy. We postulate that interstitial release of degradation products from triglycerides by lipase causes cellular disruption. Whereas phospholipase A2 and proteases do not seem to be very harmful in the early phases of cellular damage, lipase may play a major role in acute necrotizing pancreatitis.
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PMID:Role of pancreatic enzymes and their substrates in autodigestion of the pancreas. In vitro studies with isolated rat pancreatic acini. 291 45


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