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)

As a result of our own investigations on the biomorphosis of the human uterine tube it is permitted to establish that the connective tissue of the lamina propria mucosae consists of 2 stainable and histochemical different types of fibers showing age-dependent changes in distribution, arrangement and localization. On the one side it is possible to detect aldehyde fuchsin positive fibrous structures (preliminary investigations and demonstration of ones were published in SCHULTKA [1980]). These fibers can be regarded as sulphur containing scleroproteins relating to the histochemical findings. The aldehyde fuchsin positive mucosal fibrous formations arising from mesenchymal tissue during the embryonal-fetal period extend into the tubal muscular system and form a subepithelial membrane-like fibrous network. In neonatal uterine tubes the fibers spread over the mucosa as a multidimensional network, and they have a intimate contact with the epithelium. Reaching the period of the fertile age the mucosal folds contain a fine branching network. Contrary to this finding, in organs of being aged women considerable thickened fibrous structures are mainly localized near the epithelium. On the other side picrofuchsin-positive connective tissue fibers, whose tinction is visibly reduced after collagenase-digestion, are localized in the tubal mucosa. Although the increase of a coarse-fibrous picrofuchsin-stainable connective tissue can be observed in the tubal folds during the 2nd half of the 4th decade of life, these morphological changes are characteristic of organs in the postmenopausis and in the senium. Finally, 2 different reacting parts of connective tissue are formed, firstly, a aldehyde fuchsin positive connective tissue localizing near the basis of the epithelium, and, secondly, a strongly picrofuchsin-positive connective tissue filling the folds, especially perivascularly. It is discussed whether, with respect to the fibrous structures selectively detected in the human mucosa, it could be the question of distinct types of collagen fibers, in which both types would represent the morphological substratum of the type III-collagen (aldehyde fuchsin positive pepsin- and papain-sensitive disulfide bonds-containing fibers) and of the type I-collagen (picrofuchsin--positive fibers), respectively. Besides, functional importance of the aldehyde fuchsin positive fibers is discussed.
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PMID:[Detection and analysis of aldehyde fuchsin positive fibers in the connective tissue of the human oviductal mucosa II. On the biomorphosis and structural identification of the morphological substratum (author's transl)]. 616 31

Cells with electron-microscopic characteristics of myofibroblasts were isolated from baboon liver biopsy specimens by collagenase digestion and Percoll density gradient centrifugation and then cultured. The cultures consisted of only one cell type. By immunofluorescence, these cells synthesized collagen types I, III, and IV and laminin. Typical features of myofibroblasts were maintained throughout many passages in the culture. To study the effects of ethanol (and its oxidation product acetaldehyde and associated metabolite lactate) on myofibroblast collagen synthesis, the cell cultures were incubated for 24 h in a medium containing either 50 mM ethanol, 200 microM acetaldehyde, or 5 mM lactate. The cells did not contain significant alcohol dehydrogenase activity. Acetaldehyde stimulated significantly (p less than 0.05) myofibroblast collagen synthesis without changing noncollagen protein synthesis or proline pools. Lactate caused a significant (p less than 0.02) increase in intracellular proline pool and collagen synthesis. Ethanol itself did not have any effect on collagen synthesis of myofibroblasts. The stimulation of collagen synthesis of hepatic myofibroblasts by acetaldehyde and lactate may contribute to the development of alcoholic liver fibrosis, as alcohol intake is known to elevate acetaldehyde and lactate in tissues and blood.
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PMID:Acetaldehyde and lactate stimulate collagen synthesis of cultured baboon liver myofibroblasts. 638 Dec 14

The mechanisms responsible for the increased hepatic collagen deposition in alcoholic cirrhosis remain unknown. The question of whether ethanol or acetaldehyde has a direct effect on collagen and noncollagen protein production was investigated in human fibroblasts with no detectable activity of alcohol dehydrogenase to distinguish the effects of these metabolites. To eliminate environmental factors, protein production by confluent human skin, fetal and hepatic fibroblasts was studied after three passages. Cells were labeled with [5-3H]proline for 4 hr in the presence of 0.2 mM ascorbate alone or with addition of either ethanol (50 mM) or acetaldehyde (0 to 300 microM). Rates of protein production were calculated from the radioactivities of collagenase-sensitive and collagenase-resistant proteins. Skin fibroblasts from alcoholic individual either with cirrhosis or without liver disease have comparable rates of collagen and noncollagen protein production. Acetaldehyde, in a concentration found in the liver during ethanol abuse, significantly increased collagen production by human skin fibroblasts (up to 140%), fetal fibroblasts (up to 240%) and hepatic fibroblasts (up to 70%) but the addition of ethanol had no significant effect on basal collagen production. The effect of acetaldehyde was dose-related and affected noncollagen protein production in a similar manner. Acetaldehyde did not cause changes in either proline transport or the specific activity of the proline precursor pool. This newly recognized stimulation of collagen production by acetaldehyde may be a possible mechanism of fibrogenesis in alcoholic individuals.
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PMID:Acetaldehyde stimulates collagen and noncollagen protein production by human fibroblasts. 647 53

Collagen was obtained from liver tissue of rats with hydralazine-induced collagen-like syndrome. Bacterial collagenase was used to solubilize the collagen, and the aldehyde content of this material was measured using N-methyl benzothiazolone hydrazone. The aldehyde content was decreased in the in the collagen from livers of rats with collagen-like syndrome. The changes in hepatic collagen may be analogous to the effect of aging on collagen, wherein collagen cross-linking is strengthened although qualitative changes in cross-linking may lower the measurable aldehydes.
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PMID:Aldehyde content of collagen from liver of rats with collagen-like syndrome. 668 57

The preparation and potential clinical use of biodegradable microarterial grafts from rat aorta were investigated. Trypsin treated arterial segments were coated with heparin or chondroitin sulfate to reduce thrombogenicity. The samples were crosslinked with formaldehyde vapors at 4 degrees C. 50 - 100 microgram glycosaminoglycans taken up per mg aorta dry weight were resistant to washing with water for 24 hrs. The covalent crosslinks introduced by formaldehyde and resistance of the grafts to proteolytic degradation. The treated grafts were implanted on 70 rats in an infrarenal aortic position. The permeability of the aldehyde crosslinked prosthesis after 21 days by patency test was lower than the patency ratio measured with fresh autologous grafts. The glycosaminoglycans associated with the prosthesis improve the patency of the crosslinked grafts by about 48%. The resistance to bacterial collagenase of the excised grafts decreased with progressing time of implantation. In the permeable prosthesis and in the contiguous aorta, elastolytic activity was demonstrated by radial diffusion in elastin-agar gels. The grafts removed after 21 days of implantation were surrounded with scar tissue. In contrast to fresh aorta, the macromolecular hydroxyprolin in the scar was readily solubilized with pepsin. The presence of the fragmented elastin and collagen fibers in the excised graft is in favour of their resorption "in vivo".
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PMID:Biodegradable arterial prosthesis from rat aorta. 677 72

In an effort to evaluate further the concept of ethanol-induced lipid peroxidation, isolated rat hepatocytes obtained via collagenase perfusion were utilized. Hepatocytes were judged to be functionally intact based on measurements of adenosine-5-triphosphate, gluconeogenesis, bromosulphthalein uptake, and trypan blue exclusion. When hepatocytes were incubated with acetaldehyde, a metabolite of ethanol, at 100 mg% and 10 mg%, significant increases in lipid peroxidation resulted as measured by levels of malonaldehyde. Acetaldehyde-induced increases in malonaldehyde were reduced by pre-incubation with antioxidants such as Vitamin E (200 mg%) or glutathione (100 mg%).
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PMID:Acetaldehyde-induced lipid peroxidation in isolated hepatocytes. 710 Jun 31

The objective of the present investigation was to characterize further the connective tissue disorder produced by pyridoxine (vitamin B-6) deficiency, as previously evidenced by electron microscopy. Following the second post-natal week, fast growing male chicks were deprived of pyridoxine for a 1-mo period. Six weeks post-natally, blood concentrations in the experimental deficiency group had declined to deficiency levels as registered by low concentrations of pyridoxal phosphate (coenzyme form) in erythrocytes, but did not reach levels associated with neurological symptoms. Light microscopic study showed abnormalities in the extracellular matrix of the connective tissues. Collagen cross-links and the aldehyde contents were not significantly lower in cartilage and tendon collagens of vitamin B-6-deficient animals than in age-matched controls; also, their proteoglycan degrading protease and collagenase activities measured in articular cartilages were not greater. Thus, proteolysis was an unlikely alternative mechanism to account for the loss of connective tissue integrity. These results point to the need for further investigation into adhesive properties of collagen associated proteoglycans or other proteins in vitamin B-6-deficient connective tissue.
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PMID:Connective tissue integrity is lost in vitamin B-6-deficient chicks. 781 73

Alcoholic and, to a lesser extent, nonalcoholic patients with liver disease have serum antibodies to acetaldehyde-protein adducts produced in vitro. These antibodies presumably reflect the presence of adducts in the liver, but the protein that triggers this immune response has not been identified. To study this, we measured the reactivity of cytosolic proteins to rabbit IgG developed against a P-450 2E1-acetaldehyde adduct, isolated from alcohol-fed rats, that recognizes acetaldehyde-modified epitopes in proteins. Adducts were determined on Western blots by scanning densitometry of antibody-linked alkaline phosphatase activity in 4 normal livers and in needle biopsy specimens from subjects with liver disease, 17 alcoholic and 14 nonalcoholic. In all livers, except for a normal one, we found a reactive protein of at least 200 kD, similar to the collagen-acetaldehyde adduct we reported to be markedly increased in rats with experimentally induced cirrhosis. The immunostaining intensity in the alcoholic patients with liver disease was eightfold (p < 0.01) and that in nonalcoholic patients with liver disease was fourfold, greater (p < 0.02) than the weak staining in normal livers; it correlated with the degree of inflammation and serum AST or gamma-glutamyl transpeptidase activities. The adduct was reproduced on incubation of normal cytosolic proteins with 2.5 mmol/L acetaldehyde, whereas higher concentrations yielded many additional adducts; the adduct also reacted with IgG antibody to rat collagen type I and disappeared after digestion with collagenase, suggesting that the target protein is a form of collagen.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Collagen-acetaldehyde adducts in alcoholic and nonalcoholic liver diseases. 791 86

Altered degradation of extracellular matrix has been implicated in the pathogenesis of hepatic fibrosis. We studied the effect of acetaldehyde (AcCHO) on gene expression of matrix-metalloproteinase (MMP)-1 (fibroblast type- interstitial collagenase) and MMP-2 (72 kDa gelatinase-type IV collagenase) in comparison with the AcCHO effect on collagen type I and IV synthesis in cultures of fat-storing cells (FSC) isolated from normal human livers. Cultured human FSC expressed single mRNA transcripts (2.7 and 3.2 kb) specific for MMP-1 and MMP-2, respectively. AcCHO inhibited MMP-1 mRNA levels, whereas it stimulated collagen type I mRNA and protein expression. Opposite AcCHO effects were evident on MMP-2 mRNA and collagen IV synthesis, being MMP-2 up-regulated and collagen IV down-regulated. These data suggest that regulation of MMP-1 and MMP-2 genes by AcCHO may contribute to disruption of the normal basement membrane and its replacement with fibrillar collagens in the early stages of alcoholic liver fibrosis.
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PMID:Acetaldehyde regulates the gene expression of matrix-metalloproteinase-1 and -2 in human fat-storing cells. 793 38

Highly purified islets of Langerhans were prepared in the present study from adult pigs by collagenase digestion and density gradient purification. After overnight culture, the tissue was equilibrated with DMSO at 25 degrees C, supercooled to -7.5 degrees C, nucleated, slowly cooled at 0.25 degrees C/min to -40 degrees C, and stored at -130 degrees C. Then, after variable periods of storage, the islets were rapidly thawed at 37 degrees C. Postthaw actual islet and islet equivalent (150-microns sized islets) recovery were 75 +/- 7% and 66 +/- 4%, respectively. The frozen-thawed porcine islets maintained good morphology on histological staining by hematoxylin-eosin and aldehyde-fuchsin. Upon perifusion, basal insulin secretion was 43 +/- 10 and 67 +/- 18 pmol/L from noncryopreserved, control islets, and cryopreserved islets, respectively (P = 0.2). Peak insulin release at 16.7 mmol/L glucose was 85 +/- 28 pmol/L from noncryopreserved islets and 157 +/- 48 pmol/L from the frozen-thawed islets (P = 0.1). When 10 mmol/L theophylline was added to 16.7 mmol/L glucose, the secretion of the hormone peaked to 221 +/- 83 (control islets) and 479 +/- 140 pmol/L (cryopreserved islets, P = 0.1). Total insulin secretion differed significantly for the noncryopreserved and the cryopreserved islets at both 16.7 mmol/L (1412 +/- 306 vs. 3756 +/- 764 pmol/L, respectively, P = 0.007) and 16.7 mmol/L glucose plus 10 mmol/L theophylline (2161 +/- 371 vs. 7505 +/- 2075 pmol/L, respectively, P = 0.011). Normoglycemia was restored within 7 days from implantation in temporarily immunosuppressed (aL3T4 antibody) mice with streptozotocin-induced diabetes by transplanting 1500-2000 cryopreserved porcine islets under the kidney capsule. Mean survival time of frozen-thawed islet xenografts (39 +/- 3 days) was similar to that of noncryopreserved islet xenografts (43 +/- 6 days). This study demonstrates that cryogenic storage is feasible of isolated porcine islets, with the frozen-thawed pancreatic endocrine tissue maintaining morphological integrity and both in vitro and in vivo viability. Further studies are needed to define the effect of cryopreservation on the immunogenic properties of porcine islets.
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PMID:Cryogenic storage of isolated, purified porcine pancreatic islets. 810 68


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