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)

Primary functional bovine adrenal cortical cell cultures have been developed to study the factors controlling adrenal cell growth. Cells were prepared by the collagenase technique and maintained in F-12 medium containing fetal calf serum and horse serum. Cells contained abundant lipid as demonstrated by staining with Oil Red O and showed strongly positive staining for delta5,3beta-hydroxysteroid dehydrogenase. ACTH inhibited DNA synthesis and stimulated steriodogenesis in these cells. Fibroblast growth factor (FGF) was shown to be a potent stimulator of the growth of normal bovine adrenal cortical cells maintained in tissue culture. The minimal effective dose of FGF was 1 ng/ml with maximal effects being observed at 100 ng/ml. The effect of FGF was dependent on the serum concentration. Inclusion of FGF in F-12 medium containing serum permitted cloning of functional bovine adrenal cortical cells from cultures seeded at low density (4 cells/cm2). ACTH inhibited the mitogenic effects of FGF. In addition to its mitogenic action, FGF is a migratory factor for bovine adrenal cortical cells. Though ACTH inhibited the mitogenic effects of FGF, it did not block the migratory activity. Epidermal growth factor did not affect the growth of either normal bovine adrenal or functional mouse adrenal tumor cells (Y-1) in tissue culture. FGF is the first direct mitogen identified for adrenal cortical cells; ACTH opposes this mitogenic action and functions directly as a differentiate function signal.
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PMID:Control of bovine adrenal cortical cell proliferation by fibroblast growth factor. Lack of effect of epidermal growth factor. 18 90

Epidermal growth factor (EGF) is a ubiquitous fibroblast mitogen which also stimulates the synthesis of the extracellular matrix degrading metalloproteinases, collagenase, and stromelysin. Using primary cultures of human skin fibroblast, we show that these metalloproteinase mRNAs are coordinately up-regulated by EGF; and that dexamethasone, a potent inhibitor of collagenase and stromelysin synthesis, coordinately down-regulates these EGF-induced mRNAs. Nuclear run-on assays showed that EGF increased transcription of collagenase and stromelysin approximately 2-fold over the untreated control, while repression by dexamethasone was difficult to detect. However, steady state mRNA levels were induced approximately 10-fold by EGF and co-treatment with dexamethasone decreased them to below control levels, suggesting modulation of mRNA stability. Thus, we measured the half-life of these mRNAs using "pulse-chase" methodology. Typically, the half-life of EGF-induced collagenase and stromelysin mRNAs was approximately 30 h, and co-treatment with dexamethasone decreased the half-life of these mRNAs by 30-50%. Additionally, we found that the transcription inhibitor DRB stabilized EGF-induced metalloproteinase mRNAs, suggesting an mRNA degradation pathway which requires transcription. Thus our data demonstrate that collagenase and stromelysin are coordinately regulated by EGF and by dexamethasone, primarily at the level of metalloproteinase mRNA stability.
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PMID:Post-transcriptional regulation of collagenase and stromelysin gene expression by epidermal growth factor and dexamethasone in cultured human fibroblasts. 146 71

Epidermal growth factor (EGF), phorbol esters (PEs), and retinoic acid (RA) inhibit differentiated functions of thyrocytes. In the present study the inhibitory effects of these growth-promoting factors on hormone synthesis were studied in thyroid follicles cultured in type-I collagen gel, and morphologic alteration by these factors was examined by light and electron microscopy (EM). Porcine open thyroid follicles obtained by treatment with 0.1% collagenase were embedded in collagen gel and cultured in Ham's F12 medium supplemented with 6H (insulin, hydrocortisone, somatostatin, transferrin, glycyl-his-lys, and thyrotropin) + 0.5% fetal bovine serum (FBS). After 1 week these open follicles developed to closed follicles, and the medium was changed to one containing 6H + 0.5% FBS + 0.1 microM sodium iodide (NaI). Some media were supplemented with either EGF, phorbol 12-myristate 13-acetate (PMA), or all-trans RA. The closed follicles retained ability for hormone synthesis for 2 weeks after the medium change in the presence of 6H + FBS + NaI. The amounts of T4 and T3 secreted into the culture medium from day 9 to day 12 after the medium change were 60% and 45% of those from day 0 to day 4, respectively. EGF reduced production of T4 and T3 by 61% and 69%, respectively; PMA, by 87% and 99%; and RA, by 55% and 44%. In the medium supplemented with 6H + 0.5% FBS, the follicles exhibited intact polarity. Apical surfaces with microvilli were oriented to the follicular lumen and tight junctions were on the apical side of cell-to-cell contacts. Desmosomes were found on both the apical and basal halves of the cell contacts.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of epidermal growth factor, phorbol ester, and retinoic acid on hormone synthesis and morphology in porcine thyroid follicles cultured in collagen gel. 149 78

The regulation of collagenase gene expression in the human osteosarcoma-derived osteoblastic cell lines MG-63, U2-OS and human fibroblast cell line IMR-90 was investigated by Northern blot analysis. Exposure of quiescent MG-63, U2-OS and IMR-90 cells to 12-O-tetradecanoyl-phorbol-13-acetate (TPA) and 10% fetal calf serum (FCS) resulted in the induction of mRNA encoding collagenase. Epidermal growth factor (EGF) induced collagenase mRNA in the IMR-90 cell but not in the MG-63 and U2-OS cells. In the IMR-90 and MG-63 cells, EGF stimulated the transcription of the c-fos and c-jun genes encoding the transcriptional factors which interact directly with the promoter region of the human collagenase gene. Parathyroid hormone and 1,25-dihydroxy-vitamin D3 did not increase the collagenase mRNA level in both osteosarcoma cells. Recombinant interleukin-1 beta (rIL-1 beta) induced collagenase and c-jun but not c-fos mRNA in the MG-63 cell. The induction by rIL-1 beta was blocked by cycloheximide and dexamethasone. Transforming growth factor beta 1 blocked the FCS-induced collagenase gene expression but partially inhibited the rIL-1 beta-induced gene expression in the MG-63 cell. These results suggest that the collagenase activity is regulated not only by post-translational modification but also at the transcriptional level by the various factors in bone.
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PMID:[Regulation of collagenase gene expression in human osteosarcoma-derived osteoblastic cell lines]. 164 84

A three-dimensional culture model for isolated murine pelage hair follicles in a type I collagen gel has been utilized to study the effects of selected growth factors on follicle cell proliferation and release of collagenolytic factors. Cultured follicle organoids differentially express cytokeratins 6 and 14 in a pattern suggesting they contain cells of the outer root sheath, inner root sheath and follicle matrix. Using incorporation of [3H]thymidine as a measure of proliferation, follicle organoids show a peak of DNA synthesis between day 1 and 5 of culture, depending on plating density, and then have a low rate of DNA synthesis. Thymidine incorporation is stimulated by transforming growth factor-alpha (TGF-alpha) in a dose-dependent response. Only peripheral cells presumably of the outer root sheath, incorporate thymidine in basal or stimulated conditions. TGF-beta 1 and TGF-beta 2 inhibit constitutive cell proliferation and oppose growth stimulation by TGF-alpha. Hair follicles lyse the collagen gel matrix when exposed to certain cytokines. Epidermal growth factor (EGF) and TGF-alpha stimulate gel lysis, but TGF-beta 1, TGF-beta 2 and cholera toxin do not. Other skin-derived cells, such as interfollicular epidermal cells, dermal fibroblasts, or combinations thereof, do not lyse gels in this culture model even when exposed to growth factors. Combinations of EGF or TGF-alpha with TGF-beta 1 or TGF-beta 2 are synergistic for collagenase release. These cytokines stimulate release of multiple species of matrix metalloproteinases, but the 92-kDa and 72 kDa type IV procollagenases and their activated derivatives predominate on zymograms. In cytokine-stimulated follicles, both peripheral and centrally located cells in the organoids express the 72-kDa type IV collagenase and a similar immunostaining pattern is present in developing follicles in vivo. Thus growth factors appear to work in concert for certain hair follicle responses and in opposition for others. These combined actions may play a role in different phases of hair follicle development that require cell replication and invasion into the deeper dermis.
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PMID:Growth factors specifically alter hair follicle cell proliferation and collagenolytic activity alone or in combination. 196 9

Epidermal growth factor (EGF) is a potent growth factor for many tissues including the gastrointestinal tract. EGF is present in the gut lumen and is absorbed through the mucosa in the developing animals. In addition, EGF has been found to alter the immune system. In this study, we investigated the in vitro effect of EGF on normal colonic lamina propria lymphocyte DNA synthesis and ornithine decarboxylase activity. Human colonic lamina propria lymphocytes were isolated by collagenase-EDTA digestion. The effect of EGF on Con A-stimulated lymphocyte thymidine incorporation was tested. We observed that EGF suppressed DNA synthesis and ornithine decarboxylase (ODC) activity in lamina propria lymphocytes. EGF did not alter the time course of thymidine incorporation into LPL stimulated by the combination of phorbol 12,13-dibutyrate (PDB) and ionomycin. Our data suggest that (1) EGF suppresses DNA synthesis in human colonic lamina propria lymphocytes as well as ODC activity and (2) this inhibition may be mediated through protein kinase C or calcium flux. We postulate that EGF may have a role in modulating the human gut immune system.
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PMID:Epidermal growth factor regulation of DNA synthesis in human colonic lamina propria lymphocytes. 199 71

Different procedures of enzymatic digestion of rat prostatic tissue and unique sets of mitogenic factors made it possible to culture practically pure populations of epithelial and stromal cells without previous separation of the two types of cells. Keratin-positive epithelial cells dissociated by trypsin and collagenase from adult rat ventral prostate proliferated in medium WAJC 404 supplemented with epidermal growth factor, insulin, cholera toxin, and bovine pituitary extract. Proliferation of epithelial cells was completely inhibited by dexamethasone as low as 30 nM. On the other hand, fibroblast-like stromal cells released by trypsin digestion required a plastic substratum coated with calf serum or fibronectin, and proliferated in Eagle's minimum essential medium supplemented with cholera toxin, bovine pituitary extract, dexamethasone, and bovine serum albumin. Epidermal growth factor and insulin had negligible effect on proliferation of stromal cells. Physiological concentrations of dihydrotestosterone and estradiol showed no effect on proliferation of both types of cells.
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PMID:Differences in growth requirements between epithelial and stromal cells derived from rat ventral prostate in serum-free primary culture. 223 29

Intestinal smooth muscle cells play a major role in the stricture formation that complicates chronic intestinal inflammation, by proliferating and producing collagen. Transforming growth factor beta 1 has been identified as an important inflammatory mediator in the fibrotic response of human tissue to inflammation. To determine whether this mediator might be involved in intestinal fibrosis, the effect of transforming growth factor beta 1 on collagen production and proliferation by human intestinal smooth muscle cells was studied in vitro. Cells in the second passage were grown to subconfluence in medium containing 10% Nu-Serum (Collaborative Research Inc., Bedford, MA), after which the concentration of Nu-Serum was decreased. Forty-eight hours later, transforming growth factor beta 1 was added to the culture medium to achieve concentrations of 1-500 pmol/L. After 24 hours exposure to the transforming growth factor beta 1, cellular collagen synthesis was determined by the uptake of [3H]proline into collagenase-sensitive protein. Transforming growth factor beta 1 caused a 100% increase in collagen production and a 40% increase in noncollagen protein production per cell, reflecting an increase in relative collagen synthesis of 58%. This effect was maximal at a concentration of 10 pmol/L. Epidermal growth factor, by comparison, had no significant effect on relative collagen synthesis. Transforming growth factor beta 1 caused a significant increase in the uptake of methylaminoisobutyric acid, a nonmetabolized amino acid analog, into the cells at 10 pmol/L. However, this effect was small (20% increase) compared with the effect on the uptake of proline into collagen (100% increase) at this concentration. When cell proliferation was examined by the uptake of [3H]thymidine, transforming growth factor beta 1 had no effect, whereas epidermal growth factor (1000 pmol/L) caused a 94% increase. Transforming growth factor beta 1 selectively augments collagen production by human intestinal smooth muscle cells in vitro. This effect is potent and is not related to effects on either cell proliferation or amino acid uptake. These data suggest that transforming growth factor beta 1 has an important role as an inflammatory mediator in the pathogenesis of intestinal fibrosis.
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PMID:Transforming growth factor beta 1 selectively augments collagen synthesis by human intestinal smooth muscle cells. 236 93

Epidermal growth factor and cartilage-derived basic fibroblast growth factor (EGF and CD-bFGF) are mitogens shown to increase the rate of wound repair in animal models. In addition to being a mitogen for granulation tissue, CD-bFGF stimulates the recruitment of cells to the wound site. CD-bFGF and a closely-related chondrosarcoma-derived fibroblast growth factor stimulated chemotaxis of granulation tissue cells in vitro, each factor having a maximum activity at a concentration of 55 pM. Epidermal growth factor was also a potent chemoattractant for rat granulation tissue fibroblasts; however, maximum activity was obtained at 1.7 nM. Cells from all stages of wound repair were chemotactically responsive to these factors, but there was some attenuation of the response to bFGF in cells derived from fully-organized day 28 granulation tissue. Collagenase-catalyzed restructuring of collagen, an additional significant feature of wound repair, is probably critical to cell movement in an extracellular matrix. Cells derived from organizing (6-day old) sponge granulation tissue secreted latent collagenase constitutively in vitro. In the presence of serum, the production of collagenase was stimulated three-four fold by 1.8 nM bFGF derived either from cartilage or chondrosarcoma. When serum was present, as at a wound site, collagenase production was not enhanced by the addition of EGF. Cells from fully organized, day 21 sponge granulation tissue did not secrete latent collagenase constitutively and could not be stimulated to do so by the addition of EGF, bFGF, or phorbol ester. Human skin fibroblast collagenase production was also stimulated by bFGF and was refractory to EGF. While both classes of growth factor have the ability to promote wound healing, the varying responses they elicit in cell populations from the wound site emphasize the different pathways of cellular activation.
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PMID:Differential stimulation of collagenase and chemotactic activity in fibroblasts derived from rat wound repair tissue and human skin by growth factors. 253 37

Techniques are described for the isolation and cultivation of functionally intact mouse hair follicles. Follicles were isolated by collagenase digestion of dermis from 5-day-old mice and purified by differential centrifugation and filtration. Purified follicles were cultured in a Type 1 collagen matrix using Medium 199 and 8% fetal calf serum as the basic nutrient. Viability of follicles was maintained in culture since the cultures incorporated thymidine into DNA and methionine into proteins for at least 7 days. Furthermore, follicles isolated from the collagen matrix after 7 days could reattach to a plastic culture substrate or be further cultivated in a fresh collagen matrix. Functional integrity of cultured follicles was maintained since some follicle-specific cytoskeletal proteins were synthesized in vitro, and follicles isolated from the collagen matrix after 7 days formed a haired skin when recombined with dermal fibroblasts and grafted to a skin site on nude mice. Only a minority of follicles appeared to produce a mature hair shaft in vitro by morphologic criteria, however, and synthesis of the total complement of hair proteins was not observed. Cholera toxin was a strong mitogen for cultured follicles, whereas epidermal growth factor was slightly mitogenic. Epidermal growth factor stimulated the release of a Type 1 collagenase by follicle cells, however. This model system provides an opportunity for the systematic analysis of factors required for the induction of hair growth and the underlying physiology of hair follicle development. This model should also be useful for studying the role of the hair follicle in skin carcinogenesis.
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PMID:Cultivation of murine hair follicles as organoids in a collagen matrix. 282 17


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