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)

Samples from the ascending aortae from two calves affected by bovine Marfan syndrome were subjected to biochemical analyses of the connective tissue and were compared to age-matched controls. Elastin was extracted from the aortic samples with 5 M guanidine-HCl, bacterial collagenase digestion, and dithiothreitol reduction. Amino acid analysis revealed that desmosine and isodesmosine levels were the same in Marfan calves as in control animals. Gravimetric measurements of elastin, amino acid composition, soluble protein, and uronic acid values also showed no significant difference between Marfan and control tissue. In contrast to elastin, collagen in aortae of Marfan calves was significantly higher than the mean of several controls. These findings, along with other observations of this animal model, support the conclusion that the microscopic and biochemical lesions of aortic elastin in bovine Marfan syndrome likely result from defective microfibrillar metabolism. Absence of cystic medial necrosis in bovine Marfan aortae may explain normal elastin content in the animal model.
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PMID:Normal elastin content of aorta in bovine Marfan syndrome. 142 58

Collagen metabolism was studied in cutis laxa by analyzing collagen and collagenase gene expression in three dermal fibroblast strains from patients with congenital cutis laxa and comparing them with fibroblasts obtained from age-matched healthy subjects. Normal collagen synthetic activity was observed in the cutis laxa fibroblasts. An increased level of collagenase mRNA and unaltered levels of alpha 1(I) and alpha 1(III) collagen mRNA were found in all cutis laxa cell strains by dot blot hybridization. Reduced levels of elastin mRNA were also detected in these strains. However, no qualitative differences in these mRNA transcripts were detected between the control and cutis laxa fibroblasts by Northern blot analysis. Collagenase activity in fibroblast culture supernatants was then measured using fluorescein isothiocyanate (FITC)-labeled type I collagen. Increased collagenolytic activity in cutis laxa fibroblast culture supernatants was also found. These data suggest that increased collagenase expression of fibroblasts is related to the structural abnormality of dermal connective tissue in cutis laxa.
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PMID:Collagen metabolism in cutis laxa fibroblasts: increased collagenase gene expression associated with unaltered expression of type I and type III collagen. 165 70

Studies were performed to evaluate the contributions of elastin and collagen to the formation of arterial aneurysms. Dog carotid arteries and human external and internal iliac arteries were excised, mounted horizontally in a tissue bath, and were pressurized. Vessel diameter and longitudinal force were measured. the vessels were treated with elastase or collagenase. Those treated with elastase dilated, but never ruptured. Those treated with collagenase dilated still more and, in every case, ruptured. Circumferential stability resulted from recruitment of previously non-loaded collagen fibers, and from a change in geometry from a cylinder to a sphere. The laminated thrombus lining the lumen has little intrinsic strength and therefore does not confer strength to the aneurysmal wall. Treatment with elastase also reduces the retractive force exerted by the vessel in the longitudinal direction. Therefore loss of elastin permits the vessel to elongate and to become tortuous. In aged human arteries collagen also contributes a small portion of the retractive force. Progressive enlargement of aneurysms results from continued failure of wall connective tissues reflecting a) genetically defective collagen and or b) activity of the immune system.
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PMID:Pathophysiology of arterial aneurysms. 165 48

A KOH-collagenase or simple KOH digestion method was employed for scanning electron microscope (SEM) studies of elastin components in the rat thoracic aorta, mouse urinary bladder, and human ductus deferens. Immersion of the fixed tissues in 30% KOH solution for 8-10 min at 60 degrees C, with or without subsequent collagenase treatment, successfully removed collagen fibrils and basal laminae while leaving cellular and elastin elements unchanged at their original shapes and locations. The internal elastic lamina of the rat aorta appeared as a solid sheet formed by elastin fibrils 0.1-0.2 microns thick, while the medial elastic laminae were more fibrous because of the presence of numerous fine elastin fibers on their surface. Adventitial elastin fibers were of a cord-like shape complicatedly entangled among the adventitial fibroblasts. These fibers were seen as bundles of fibrils 0.1-0.2 microns thick. In the mouse urinary bladder, elastin formed a thin lace-like sheet just beneath the serosal covering of the peritoneum. This sheet was composed of small bundles of fine (0.1-0.2 microns thick) fibrils. The external connective tissue of the human ductus deferens was made up of a three-dimensional loose network of elastin fibers 0.1-1.5 microns thick. These fibers also appeared as bundles of the fine fibrils. These findings indicate that the present method is useful for SEM studies of elastin as well as cellular components in various tissues and organs. This study also maintains that elastin fibers and laminae are basically composed of unit fibrils of 0.1-0.2 microns thickness. As elastin components are arranged specific to individual organs and tissues, it is reasonable that these components are concerned in the characteristic mechanical properties of these tissues and organs.
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PMID:Scanning electron microscopic studies of tissue elastin components exposed by a KOH-collagenase or simple KOH digestion method. 166 55

Several collagen types (mainly types I, III, V and VI), elastin, fibronectin and some proteoglycans are active constituents of uterine myometer. They surround and associate smooth muscle cells. The type I collagen biosynthesis in the uterus is under the positive control of estrogens that in addition repress the collagenase secretion and in this way prevent collagen from degradation. The cervical softening and dilation are caused by a progressive degradation of collagen and by the synthesis of an additional proteoglycan that separates and disorganizes the collagen fibres. Prostaglandin E2 and relaxin participate in the activation of collagenases. After delivery, the drop in estrogens and progesterone permits collagenases to rapidly degrade uterine collagen in excess.
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PMID:[Uterine collagens. General review]. 166 55

SR 26831 ([[5-(2-chloro-benzyl-2-(terbutyloxycarbonyl)]-4,5,6,7- tetrahydrothieno(3,2-c)pyridine]N-oxide) is the first member of a new class of human leukocyte elastase inhibitors. SR 26831 inhibited in a dose-dependent manner elastases from human leukocytes or pancreas with IC50 values of 80 +/- 2.6 nM and 4.8 +/- 0.12 microM, respectively. Steady-state studies revealed that SR 26831 behaved like a noncompetitive, irreversible inhibitor of both types of enzymes. SR 26831 inhibited in a dose-dependent manner degradation of [3H]elastin and [3H]collagens (types I and IV) by human leukocyte elastase (IC50 values were between 1.2 and 1.8 microM). In this respect, SR 26831 was 3- to 20-fold more active than alpha-1-antitrypsin. SR 26831 was also highly selective for elastases inasmuch as it did not inhibit pepsin, collagenase, trypsin, alpha-chymotrypsin, factor Xa, plasmin, kallikrein, cathepsins B, C, D and G and thrombin. In the rabbit, SR 26831 was cleared rapidly from blood after i.v. injection, but affected intracellular leukocyte elastase activity shortly after either i.v. or p.o. administration. In the rat, i.v. or p.o. administration of SR 26831 prevented in a dose-dependent manner acute lung injury induced by intratracheal instillation of human leukocyte elastase. SR 26831 (1 mg/kg) was still efficient when it was administered 90 min before elastase instillation and was also able to limit further hemorrhage development in response to elastase, after it had begun. SR 26831 may therefore be of therapeutic value in the treatment of diseases such as rheumatoid arthritis or pulmonary emphysema thought to be due to the destructive action of leukocyte elastase.
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PMID:Biochemical and pharmacological activities of SR 26831, a potent and selective elastase inhibitor. 173 26

The Hutchinson-Gilford syndrome (progeria) is a rare disorder in childhood characterized by premature and accelerated aging. This study reports the effect of a potent growth factor, EGF, on the proliferative capacities and extracellular matrix macromolecules and collagenase expression of two strains of progeria skin-derived cells. At low population doubling levels (PDL less than 10), confluent cultures of progeria fibroblasts made quiescent by lowering the concentration of serum in the medium did not respond to EGF while the mitotic activity of normal PDL-matched fibroblasts was almost maximally restored upon addition of EGF. No obvious difference between normal and low PDL progeria fibroblasts was observed in the number and in the affinity of the receptors measured by [125I]EGF binding. The synthesis of collagen and non-collagen proteins was similar in normal and affected cells at low and high serum concentration and both types of cells responded to EGF by a specific inhibition of collagen synthesis. Besides a normal level of mRNA coding for type I and type III collagens, collagenase and laminin, progeria fibroblasts expressed a high level of elastin and type IV collagen mRNA. Like normal fibroblasts, progeria cells responded to EGF by a decrease in the level of mRNA for fibrillar collagens and elastin. In contrast, a complete lack of response to EGF was observed for collagenase mRNA whereas the expression of this enzyme was strikingly induced by EGF in normal PDL-matched cells. The abnormal expression of type IV collagen was not significantly modified by EGF. At PDL greater than 10, progeria cells exhibited features of senescence. A significant reduction of collagen synthesis was observed and no further inhibition by EGF was recorded.
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PMID:Altered response of progeria fibroblasts to epidermal growth factor. 180 12

Experiments were performed to examine longitudinal retractive force in pressurized arteries in vitro. This force opposes vessel elongation and prevents the development of tortuosity. Common carotid arteries were excised from six adult dogs and external iliac arteries were excised from six elderly male humans at autopsy. Each vessel was mounted in a tissue bath at in situ length and was pressurized. Longitudinal retractive force was measured under control conditions and after treatment with elastase or collagenase. Results showed that, in the dog vessels, elastin provides all of the longitudinal retractive force. In the aged human vessels, both elastin and collagen provide longitudinal retractive force, with elastin contributing the much greater part.
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PMID:Longitudinal retractive force in pressurized dog and human arteries. 215 43

Skh:HR-1 hairless mice were irradiated chronically with sub-erythemal doses of UVB radiation, and a number of biochemical parameters in the skin were determined after 6, 12, 18, and 24 wk of exposure. The parameters measured were water, collagen, elastin, and glycosaminoglycan content; collagenase and elastase levels; and Bz-Tyr-OEt (N-benzoyl-L-tyrosine ethyl ester) and BAPNA (alpha-N-benzoyl-DL-arginine-p-nitroanilide) hydrolyzing activities. Data for UVB radiation-exposed and chronological age-matched control mice were compared with respect to unit area and to unit mass of skin. On a unit area of skin basis, UVB radiation exposure increased the level of most parameters. The particular exceptions were collagen and collagenase which remained constant. On a mass of skin basis, though, there is an apparent decrease in collagen content because of the increase in the other skin components. This suggests that there is insufficient collagen in UVB radiation-exposed skin to support the increasing mass of the tissue.
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PMID:Chronic ultraviolet B radiation-induced biochemical changes in the skin of hairless mice. 215 30

Elastin was purified from baboon aorta using Achromobacter collagenase and its susceptibility to proteolysis by various enzymes was studied. Human leukocyte elastase (HLE) hydrolysed baboon aortic elastin 8 times faster than human cathepsin G. Bovine chymotrypsin had virtually no activity against this substrate. The kinetic constants V and [S50] of aortic elastin hydrolysis by HLE (0.15 microM) were 0.00286 mg x ml-1 x min-1 and 0.158 mg x ml-1, respectively. One mg of this elastin could be saturated with 5.6 micrograms of HLE. As with elastins isolated from other sources, the hydrolysis of baboon aortic elastin by HLE was highly sensitive to ionic strength, and a biphasic effect was obtained with increasing NaCl concentrations. A nearly 2-fold stimulation of elastolysis was observed at a 0.15M NaCl concentration. Further increase in ionic strength led to a continuous decrease of the rate of elastolysis which paralleled the decrease of adsorption of elastase to baboon aortic elastin. Cathepsin G, but not bovine alpha-chymotrypsin, was able to stimulate the rate of hydrolysis of baboon aortic elastin by HLE. A 1.7 fold stimulation was observed for a 1:1 molar ratio of the two proteinases and rose to 2.1 for a HLE/Cat. G ratio equal to 8.
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PMID:Susceptibility of baboon aorta elastin to proteolysis. 216 85


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