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

---

Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was performed to characterize the matrix metalloproteinases (MMPs) produced during the degradation of cotton-wrapped cartilage, implanted into the murine air pouch. One, two or three weeks following cartilage implantation, proteins were extracted from the granulation tissue and MMP activities were measured. Although collagenase-, gelatinase- and stromelysin-like activities were detected at each time point, gelatinase activity was by far the most prominent. These enzymes were inhibited by EDTA, but not by NEM or PMSF, indicating that these proteinases were metalloproteinases. Gelatin zymography revealed several lysis zones amongst which a major 92-kDa band shifted to 83- and 68-kDa species during the course of implantation. The emergence of these species coincided with enhanced gelatinolytic activity and collagen loss from the implanted cartilage.
...
PMID:Gelatinase is the main matrix metalloproteinase involved in granuloma-induced cartilage degradation. 133 18

Tumor proteinases are considered to be important in the process of cancer invasion and metastasis. We have proposed that the surface membrane localization of these proteinases places them in an optimal site to facilitate the invasion of surrounding extracellular matrix. In this study, we have used the organic solvent, n-butanol, and the detergent, n-octyl-glucoside, to sequentially extract metalloproteinases from crude plasma membranes of human RWP-I pancreatic cancer cells. Anion exchange chromatography and gel permeation chromatography were employed to further purify enzymes with the capacity to degrade gelatin, type-IV collagen, and carboxymethylated transferrin. Gelatin zymography was used to demonstrate proteinase bands of 92, 70 and 62-kDa. Immunoblotting of solubilized, partially purified pancreatic cancer plasma membrane proteins using polyclonal rabbit antibodies, which have specificity for type-IV collagenase/gelatinase, resulted in the recognition of a 70-kDa protein, but not the 92-kDa gelatinase. A type-IV collagenase/gelatinase of 68-kDa was similarly identified in A2058 human melanoma cancer cell plasma membranes.
...
PMID:Extraction of type-IV collagenase/gelatinase from plasma membranes of human cancer cells. 216 1

Gelatin microspheres with a diameter less than 2 microns were synthesized by means of cross-linking with glutaraldehyde. When the microspheres were subjected to degradation in phosphate-buffered saline solution containing collagenase, the digestion of microspheres was found to decrease with increasing cross-linking. Interferon was incorporated in the microspheres at a high trapping efficiency, and the rate of interferon release from the microspheres was regulated by the extent of cross-linking with glutaraldehyde. Gelatin microspheres incorporating interferon-alpha were readily phagocytosed by macrophages, regardless of the extent of cross-linking, and the phagocytosed microspheres were observed to be degraded gradually in the interior of macrophages, resulting in the slow release of the incorporated interferon in the cells.
...
PMID:Synthesis of gelatin microspheres containing interferon. 247 65

To clarify the destruction of connective tissue in ulcerated regions, collagenase and gelatinolytic activities in homogenates of rat acetic acid-induced ulcers were examined. Gelatinolytic activity in the ulcerated regions was significantly higher than that in normal tissues. Collagenase, however, was not detectable. Gelatin-gel-electrophoresis showed that the gelatinolytic activity was due to several species, some of which crossreacted with a sheep anti-(rabbit prostromelysin) antibody. The H2-blocker, famotidine, significantly depressed the gelatinolytic activity in the ulcerated regions. Thus, both stromelysin and gelatinolytic enzymes may play important roles in the degradation of the basement membrane, especially type IV collagen.
...
PMID:Characterization of metalloproteinases in rat gastric tissues with acetic acid-induced ulcers. 259 86

Fluorescent probes have been used to obtain dissociation constants for the fluid-phase interaction of human plasma fibronectin and several of its gelatin-binding fragments with purified alpha chains of type I rat tail collagen, as well as with a cyanogen bromide fragment (CB7) of the alpha 1 chain in 0.02 M Tris buffer containing 0.15 M NaCl at pH 7.4. Addition of fibronectin to fluorescein-labeled collagen chains caused a dose-dependent increase in the fluorescence anisotropy which continued over several logs of titrant concentration. Scatchard-type plots of the anisotropy response were biphasic indicating the presence of one or more weak sites (Kd greater than microM) along the collagen chain in addition to a strong site characterized by Kd = 1.3 X 10(-8) M at 25 degrees C. Gelatin-binding fragments with Mr = 42,000, 60,000, and 72,000 also produced a biphasic response with Kd values for the high affinity site being 10- to 20-fold greater than for intact fibronectin. Binding of fibronectin and its fragments to fluorescent-labeled CB7 was essentially the same as to the whole alpha 1 chain. In all cases, the anisotropy response could be reversed or prevented by addition of excess unlabeled gelatin or CB7, but not by synthetic peptides spanning the collagenase cleavage site of alpha 1 (I). Studies of the temperature dependence of Kd for binding of fibronectin to the high affinity site on alpha 1 produced a value of +16 kcal/mol for the enthalpy of dissociation below 30 degrees C. Above this temperature, fibronectin appeared to undergo a subtle conformational transition characterization by a reduced affinity for collagen. This transition occurred in whole fibronectin but not in the gelatin-binding fragments and may involve disruption of intramolecular interactions between different domains.
...
PMID:Interaction of fibronectin and its gelatin-binding domains with fluorescent-labeled chains of type I collagen. 312 86

A gelatin sponge model system for tumor cell inoculation and retrieval of tumor-associated leukocytes is described. Gelatin sponges pre-implanted in nude mice harboring tumorigenic Chinese hamster ovary cells (line CHO) were examined at 2 and 11 days after injection of tumor cells for tumor cell content and leukocyte accumulation after digesting the sponge matrix in collagenase solution. The data indicate a progressive influx of host cells consisting primarily of macrophages, neutrophils and lymphocytes. The total number of viable tumor cells as well as the fraction of surviving tumor cells with clonogenic potential also increased with tumor age. Blank sponges not harboring tumor cells elicited an inflammatory response in the animals which did not change appreciably with length of sponge residence. However, when the sponges were harboring tumor cells, the accumulation of host leukocytes far exceeded that which occurred in blank sponges. This observation suggests a host response directed toward the tumor which is absent in animals bearing blank sponges. Apart from providing anchorage for injected cells, the gelatin sponge, by virtue of its digestibility in collagenase, makes possible the easy retrieval and precise quantitation of tumor-associated host cells.
...
PMID:A gelatin sponge model for studying tumor growth: quantitation of tumor cells and leukocytes in the CHO tumor. 359 90

Gelatin-specific protease activity from hamster lung fibroblasts and their culture media is described. The fibroblasts were derived from hamster lung explant cultures. The gelatin-specific protease activity is latent and seen only after dialysis of either cells or media. The enzyme activity shares many properties of previously reported gelatinases. The activity is inhibited by EDTA, cysteine, and dithioerythritol, whereas it is not inhibited by p-chloromecuribenzoate, N-ethyl maleimide, or phenylmethylsulfonyl fluoride. Of all substrates tested, activity was observed only against gelatin and not against other substrates tested. It was inactive toward collagen, elastin, and methemoglobin. This enzyme may have a role in the digestion of collagen that has been previously cleaved by mammalian collagenase.
...
PMID:A gelatin-specific protease from hamster lung-derived cell cultures. 630 44

The number and approximate molecular weights of extracellular alkaline proteases produced by Vibrio alginolyticus were determined by gelatin-PAGE. Three major bands of protease activity with apparent molecular weights of approximately 28 000, 22 500 and 19 500 (proteases 1, 2 and 3, respectively) and two minor bands of protease activity with apparent molecular weights of approximately 15 500 and 14 500 (proteases 4 and 5, respectively) were obtained after gelatin-PAGE. The activities of the five proteases were inhibited by serine protease inhibitors but their activities were not affected by inhibitors of trypsin-like enzymes. Histidine, which inhibited V. alginolyticus collagenase, did not inhibit the activities of the alkaline serine proteases. The production of protease 1, however, was enhanced by histidine. Protease 1 production was also affected by temperature and production was depressed at 37 degrees C. Gelatin-PAGE of a commercial V. alginolyticus collagenase preparation revealed four bands of activity which were identified as collagenases with apparent molecular weights of approximately 45 000, 38 500, 33 500 and 31 000. The collagenase preparation was contaminated with two serine proteases. The release of [3H]proline from collagen matrices produced by smooth muscle cells was shown to be a sensitive assay for bacterial collagenases and was used to show that V. alginolyticus produced a basal constitutive level of extracellular collagenase. The constitutive levels of collagenase were affected by aeration.
...
PMID:Characterization of extracellular alkaline proteases and collagenase induction in Vibrio alginolyticus. 631 26

Abnormalities in extracellular matrix degradation may play a pathogenetic role in diabetic nephropathy. Cultured renal mesangial cells are known to synthesize increased amounts of matrix proteins when incubated in high glucose media (e.g., 30 mmol/l). However, the effect of glucose loading on degradative enzymes is unknown. Primary cultures of rat mesangial cells were grown until confluent in the presence of fetal calf serum (FCS) and insulin (0.67 U/ml). Cells were then cultured for 7 days in plastic wells in either 10 or 30 mmol/l glucose media containing neither FCS nor insulin. Collagenase activity in media were determined by zymography and quantitative spectrofluorometry. Cathepsin B and D activities in cell extracts were measured by spectrofluorometry (using the fluorescent substrate Z-Arg-Arg-7-amido-4-methylcoumarin) and 125I-labeled hemoglobin digestion, respectively. Gelatin-degrading activity of live mesangial cells was also determined. mRNA levels for collagenase IV, cathepsin B, and cathepsin D were determined by Northern analysis. A major band of collagenase activity with a molecular size of 72 kDa was observed in all mesangial cell media. Exposure of cells to high glucose media resulted in significant reductions in collagenase and cathepsin B activities as well as impairment in gelatin-degrading activity. Collagenase IV and cathepsin B and D mRNA levels were also decreased by glucose loading. To exclude the possibility that glucose loading was injurious to cells, 3H-leucine uptake (as a measure of protein synthesis) and membrane alkaline phosphatase activity (as a biochemical marker of viability) were not affected by the high glucose condition.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Decreased degradative enzymes in mesangial cells cultured in high glucose media. 762 99

Radiation-induced damage in the central nervous system (CNS) is believed to be targeted to glial or endothelial cells or both, although the pathophysiology of the process is still poorly understood. In this study, we irradiated rat astrocytes with single doses of X-rays and then estimated the levels of tissue plasminogen activator (tPA) and collagenase in serum-free medium and cell extracts at different times. Fibrin zymography revealed increased levels of intracellular tPA activity at 12 hr after irradiation. Gelatin zymography showed continuously increasing levels of extracellular 72-kDa type-IV collagenase after irradiation. Quantitative enzymatic activities by densitometry showed a 3- to 4-fold elevation in the level of the intracellular tPA activity at 12 hr and a 5- to 6-fold increase in the level of the extracellular 72-kDa type-IV collagenase activity at 48 hr. An ELISA with specific antibodies for tPA and 72-kDa type-IV collagenase indicated a 5-fold increase in the level of tPA at 12 hr and a more-than-7-fold increase in the level of 72-kDa type-IV collagenase at 48 hr. This study adds considerable credibility to the proposed role of plasminogen activators and type-IV collagenase in the development of CNS damage after radiotherapy for brain tumors.
...
PMID:Induction of tissue-type plasminogen activator and 72-kDa type-IV collagenase by ionizing radiation in rat astrocytes. 831 4


1 2 3 4 5 6 7 8 Next >>

---