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)

By electron microscopic studies collagenase, hyaluronidase, HCl, ascorbic acid, and iron ions have been found to attack the collagen fibers of bovine vitreous. Because of the possible role of ascorbic acid in collagen synthesis and the ability of ascorbic acid to degrade hyaluronic acid and collagen we suggest that the ascorbic acid of the vitreous essentially participates in construction and metabolism of the vitreous body.
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PMID:[Electron microscopic investigations of vitreous collagen after treating the vitreous with liquefying substances (author's transl)]. 16 9

The action of hydralazine on collagen prolyl hydroxylation was studied in a cell culture system using WI-38 fibroblasts. The prolyl hydroxylation level was determined by a method involving the digestion of collagen by bacterial collagenase and the examination of specific peptides. The presence of low concentrations of hydralazine (0.2 mM) in both "young" and "old" fibroblast cultures strongly inhibited collagen prolyl hydroxylation. The degree of inhibition was greater in serum-deficient cultures. No significant improvement in the degree of hydroxylation was observed by increasing either ascorbate or iron levels in the hydralazine-containing cultures in which hydroxylation was inhibited. Some of the reported side effects of hydralazine seen in patients might be related to its inhibitory effects on mixed function oxidative (MFO) hydroxylation systems. While the ascorbate dependence of the prolyl hydroxylase system of WI-38 decreased with the "age" of the culture, hydralazine inhibition of hydroxylation was dramatic with cultures of all "ages".
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PMID:Collagen prolyl hydroxylation in WI-38 fibroblast cultures: action of hydralazine. 85 25

Suspensions of renal proximal tubules (RPT) are the in vitro model for many biochemical and physiologic investigations. Inasmuch as there are numerous procedures for tubule isolation and the more commonly used enzymatic procedures may disrupt the basement membrane, there is a need for information comparing the influence of various isolation methods on RPT viability and function in long-term suspension. Rabbit RPT isolated a) enzymatically (ENZ) by in vitro collagenase digestion and Percoll size and density purification, and b) mechanically (MECH) by in vitro iron oxide perfusion and purification by sieving and magnetic removal of glomeruli were compared for viability, morphology, and functional stability during long-term suspension. RPT isolated by ENZ and MECH methods had excellent viability (less than 15% lactate dehydrogenase release), limited lipid peroxidation (less than 0.2 nmol MDA.mg protein-1), and stable nystatin-stimulated oxygen consumption (QO2) (38 and 36 nmol O2.mg protein-1.min-1) throughout 24 h of incubation. Basal QO2 was higher in ENZ than MECH tubules (27 and 19 nmol O2.mg protein-1.min-1, respectively), and was unchanged over 24 h in each preparation. The higher basal QO2 in ENZ tubules was ouabain-sensitive, suggesting an increased rate of Na+,K(+)-ATPase activity in these tubules. Total glutathione content (oxidized + reduced) in ENZ and MECH tubules increased over the 24-h incubation from 8 to 18 nmol.mg protein-1. gamma-Glutamyltranspeptidase (GGT) activity of the RPT homogenates was equivalent in both preparations and stable over time. The ratio of suspension GGT activity to homogenate GGT activity doubled (0.4 to 0.8) during the incubation period. MECH tubules retained their tubule structure during 24 h of incubation whereas the ENZ tubules had a striking loss of tubular morphology over time. These results show that ENZ- and MECH-isolated renal proximal tubule suspensions exhibit similar biochemical properties in long-term incubations but differ in ouabain-sensitive QO2 and the retention of tubular morphology. The loss of tubular morphology and the increase in the rate of Na+,K(+)-ATPase activity in ENZ tubules may be secondary to the disruption of the tubular basement membrane.
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PMID:Differences in enzymatic and mechanical isolated rabbit renal proximal tubules: comparison in long-term incubation. 197 32

Free radical damage has the potential to significantly affect the behavior of cells in culture. In this study the effects of antioxidants (superoxide dismutase, catalase, and vitamin E) and lowered oxygen tension (1% oxygen) on primary culture of rat mammary epithelial cells were examined. Rat mammary epithelial cells were dissociated in collagenase with or without the addition of antioxidants and low oxygen tension, then cultured for 10 d in rat-tail collagen gel matrix and fed with Dulbecco's modified Eagle's F12 medium supplemented with various hormones and growth factors. Growth potential of the mammary cells was enhanced when antioxidants and low oxygen tension were used, alone or in combination, during the cell dissociation period. Using antioxidants and low oxygen tension during the culture period failed to improve growth potential regardless whether cells were dissociated in standard conditions or with antioxidants and low oxygen tension. The use of antioxidants and low oxygen tension during the cell dissociation period also reduced the degree of keratinization of the cells after 10 d of culture. Using antioxidants and low oxygen tension during the cell culture period did not further reduce keratinization if antioxidants and low oxygen tension were used during the dissociation period, but were effective in reducing keratinization if cells were dissociated in standard condition. In this system, antioxidants and low oxygen tension reduced lipid peroxidation during the cell dissociation period. An iron chelator, desferal, can also reduce lipid peroxidation and enhance growth when used during cell dissociation, suggesting the enhanced growth potential by the addition of antioxidants and low oxygen to be due to the reduction of lipid peroxidation.
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PMID:Effects of antioxidants and reduced oxygen tension on rat mammary epithelial cells in culture. 203 19

Cationic glucose oxidase, prepared by amidation of its free carboxylic groups, has prolonged retention in tissues, resulting in sustained release of hydrogen peroxide generated during oxidation of endogenous glucose. Increased levels of hydrogen peroxide can inhibit superoxide dismutase activity, thereby promoting reduction of transition metal ions, particularly iron and copper, by superoxide anions. Therefore, hydrogen peroxide can generate highly reactive hydroxyl radicals through a superoxide-driven Fenton reaction. Amidated glucose oxidase injected into rabbit cornea produces corneal opacification within 3-4 days and severe corneal damage by 7 days. Ultrastructural studies revealed typical tissue lesions observed in corneal melting. Heat-inactivated amidated glucose oxidase had no effect during the first 3-4 days. However, a gradual opacification occurred thereafter, resulting in some cases, in a severe opacity by 7 days. These results are consistent with an oxidative attack on corneal glycoconjugates by radicals derived from glucose oxidase-generated hydrogen peroxide during the first 3-4 days. Invading phagocytic cells are responsible for lesions observed with the inactive enzyme and for the progression of the initial lesions caused by the active enzyme. Stimulated phagocytic cells not only produce active oxygen species during the respiratory burst, but also release neutral collagenase and acid lysosomal hydrolases that contribute to and amplify the degradation of the extracellular matrix.
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PMID:Role of active oxygen species in corneal ulceration. Effect of hydrogen peroxide generated in situ. 215 13

The early histological, biochemical, and biomechanical characteristics of the anterior cruciate ligament (ACL) were determined in a rabbit model of acute hemarthrosis. The ACLs of 19 rabbits were given seven consecutive daily knee injections of 2 ml of fresh autologous blood, and then compared to contralateral ACLs from control knees injected with 2 ml of lactated Ringer's solution daily for 7 days. The rabbits were then sacrificed. Synovial proliferation with iron deposition within synoviocytes was observed; however, the architecture of the ACL was maintained. Additionally, the total collagen content, collagenase activity, and biomechanical properties of the ACL were unaltered.
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PMID:Acute hemarthrosis: a histological, biochemical, and biomechanical correlation of early effects on the anterior cruciate ligament in a rabbit model. 216 90

The ability of various reactive oxygen species and serine proteases to activate latent collagenase (matrix metalloproteinase-1) purified from human neutrophils was examined. Latent 70-75 kD human neutrophil collagenase (HNC) was efficiently activated by known non-proteolytic activators phenylmercuric chloride (an organomercurial compound) and gold thioglucose (Au(I)-salt). Corresponding degree of activation was achieved by reactive oxygen species including hypochlorous acid (HOCl), hydrogen peroxide (H2O2) and hydroxyl radical generated by hypoxanthine/xanthine oxidase (HX/XAO). The presence of trace amounts of iron and EDTA were necessary and even enhanced H2O2 induced activation of latent HNC. This activation could be abolished by an iron chelator desferrioxamine and a hydroxyl radical scavenger mannitol. HOCl induced activation of latent HNC was not affected by desferrioxamine and mannitol. Thus, these compounds do not inhibit the active/activated form of HNC. Latent HNC could also be activated by trypsin and chymotrypsin but not by plasmin and plasma kallikrein. The ability of mannitol and desferrioxamine to inhibit the H2O2-induced activation of HNC suggests the transition metal dependent Fenton reaction to be responsible for localized and/or site-specific generation of hydroxyl radical/hydroxyl radical -like oxidants to act as the activating oxygen species. Our results support the ability of myeloperoxidase derived HOCl to act as a direct oxidative activator of HNC and further suggest the existence of a new/alternative oxidative activation pathway of HNC involving hydroxyl radical.
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PMID:Activation of latent human neutrophil collagenase by reactive oxygen species and serine proteases. 217 13

Interleukin-1 (IL-1) is secreted by macrophages, macrophage-like cells (e.g. Langerhans cells) and by astrocytes, keratinocytes, fibroblasts or natural killer cells. IL-1 is directly involved in the activation of helper T lymphocytes. However, it has been shown that IL-1 also induces release of collagenase and prostaglandins by fibroblasts. Furthermore, injections of IL-1 into animals are followed by fever, leukocytosis, increased serum concentrations of fibrinogen, serum amyloid A and haptoglobin, and decreased levels of iron and zinc. IL-1 has been extracted from experimental granuloma and from tissues of animals with endotoxinemia. Synovial fluids from patients with osteoarthritis contain significant amounts of IL-1. All in all, IL-1 may be ultimately involved in the development of fever and fibrosis, in the destruction of joints and the activation of T lymphocytes during inflammatory processes.
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PMID:[Interleukin 1]. 241 45

Collagenases are known to be associated with tissue destruction in chronic inflammatory diseases such as periodontal diseases and rheumatoid arthritis. Collagenases are secreted by circulating inflammatory cells (polymorphonuclear leukocytes and monocytes), resident mesenchymal cells and epithelial cells in latent forms, which can be activated by proteases and compounds reacting with protein thiol groups. We have studied here the effects of oxygen-derived free radicals (ODFR) on latent human neutrophil collagenase. Also, in order to elucidate the cellular sources of collagenases, the ability of human gingival crevicular fluid (GCF) collagenases both from adult periodontitis (AP) and localized juvenile periodontitis (LJP) patients to degrade soluble interstitial collagen types I and II was studied. ODFR generated by the xanthine oxidase/hypoxanthine system in the presence of trace amounts of iron and EDTA activated latent neutrophil collagenase to an equal extent as the known activators phenylmercuric chloride and gold thioglucose. ODFR activation was inhibited by desferoxamine and mannitol as well as by superoxide dismutase and catalase. Clear differences in the susceptibility of collagen types I and II to AP and LJP GCF collagenases were observed. AP GCF collagenase degraded type I and II collagens at equal rates, resembling the substrate-specificity of human neutrophil collagenase. LJP GCF collagenase degraded type I collagen considerably faster than type II collagen, which was only negligibly degraded. This corresponds to the substrate specificity of fibroblast collagenase. Zymographic evaluation of gelatinolytic proteases showed the presence of 90 and 68 kD gelatinases in both AP and LJP GCF. Non-proteolytic means apparently provide a potent activation pathway of neutrophil collagenase in vivo and the hydroxyl radical was identified to be one of the potent activating oxidants.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Non-proteolytic activation of latent human neutrophil collagenase and its role in matrix destruction in periodontal diseases. 256 61

Polycationic labels such as cationized ferritin and colloidal iron were used to evaluate the surface negative charges over the mandibular condyles of ICR mice. The effects of neuraminidase, hyaluronidase, pronase, and collagenase on the binding of cationized ferritin and colloidal iron particles to the condylar articular surface were also studied. The results of this study clearly indicate that the surface area of the cartilaginous condyle is negatively charged and that its composition consists mainly of a collagenous material embedded within a proteinaceous matrix. With age, a substantial decrease in the density of negative charges took place along the surface area and, in particular, in the context of sialic acid residues. It is, therefore, possible that the reduction in cartilage surface charge might be associated with the onset of osteoarthritic changes commonly seen in aging humans and experimental animals.
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PMID:Cartilage surface charge. A possible determinant in aging and osteoarthritic processes. 298 74


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