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)

The basal levels of mRNAs encoding two metalloproteinases, collagenase and stromelysin, were increased as a function of in vitro serial subcultivation (cellular aging) of human fibroblasts. Procollagenase and prostromelysin synthesis and secretion were also greater in the old cultures (late passage). In contrast, the steady-state expression of mRNA for an inhibitor of metalloproteinases, tissue inhibitor of metalloproteinase-1 (TIMP-1), in late-passage cultures was lower than that in young cell cultures (early passage). Each mRNA was analyzed using total RNA preparations isolated from normal fibroblast cultures at different phases of the in vitro life span and from cultures derived from donors with the premature senescence syndromes characterized as Werner syndrome, progeria (Hutchinson-Gilford) syndrome, or Cockayne syndrome. In normal cell cultures expression of metalloproteinase mRNAs was increased after the culture had completed greater than 90% of the in vitro life span, and the reduction in TIMP-1 mRNA expression occurred after the culture had completed greater than 74% of the in vitro lifespan. In Werner syndrome cultures expression of metalloproteinase and TIMP-1 mRNAs was similar to the level of expression observed in late-passage cell cultures. Levels of metalloproteinase and TIMP-1 mRNA expression in progeria and Cockayne syndromes were similar to those of early-passage cell cultures. To determine if young and old cells were each responsive to mediators of metalloproteinase synthesis, cultures were treated with phorbol ester or cytokines. 12-O-tetradecanoylphorbol-13-acetate treatment increased the steady-state levels of all three mRNAs in young, old, and Werner syndrome cultures and increased procollagenase levels in all cultures. Early- and late-passage cell cultures also responded to cytokines. Interleukin-1 alpha treatment increased collagenase and stromelysin mRNA levels while transforming growth factor-beta reduced the steady-state levels of both transcripts. Neither cytokine affected the steady-state level of TIMP-1 mRNA. The results indicate that in vitro cellular aging is associated with changes in expression of mRNAs encoding proteins that mediate inflammatory responses and connective tissue remodeling.
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PMID:Differential expression of metalloproteinase and tissue inhibitor of metalloproteinase genes in aged human fibroblasts. 132 16

Although Werner's syndrome (WS) is a premature aging disease and its fibroblasts typically grow poorly in culture, WS may cause abnormalities in connective tissue metabolism that are seldom seen in normal aging, such as scleroderma-like skin. In a preliminary report, we described increased collagen synthesis in fibroblasts derived from two WS patients. The present study was undertaken to determine the degree of the regulation of collagen gene expression in dermal fibroblasts from two other patients. Overproduction of collagenase sensitive protein was observed in WS fibroblasts. Collagen m-RNA levels, that were determined by hybridization of RNA blots with specific cDNA were about 2 times greater than those in the control cells. These results suggest that control of collagen synthesis in WS fibroblasts is altered at the transcriptional level.
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PMID:Increased collagen synthesis accompanying elevated m-RNA levels in cultured Werner's syndrome fibroblasts. 229 93

Comparison of the proteins secreted by early and late passage cell cultures of human fibroblasts revealed a high level of immunoreactive collagenase (Mr = 55,000 Da and 58,000 Da) in the late passage cell culture conditioned medium. Both molecular weight species reacted with a monoclonal anticollagenase antibody and were apparently glycosylation varaents of the same protein. The question of whether the apparent age-dependent differences in collagenase synthesis reflected changes in protein synthesis or secretion was addressed by assaying immunoreactive collagenase and collagenase mRNA. Immunofluorescence microscopy of cellular collagenase revealed that the percentage of collagenase positive cells ranged from 1 to 6% (early passage) to 35 to 46% (late passage) indicating that the late passage cells had higher basal levels of collagenase synthesis. Later passage cultures also secreted higher levels of immunoprecipitable collagenase into the culture medium and Northern analysis established that the basal level of collagenase mRNA was also 10 times greater in late passage cells. High basal levels of collagenase were also observed in fibroblasts cultured from an in vivo aged donor and from donors with Werner's syndrome. Collagenase production was induced in both early and late passage cell cultures by exposure to fibroblast extracellular matrix, fibroblast conditioned media, polypeptide growth factors, or phorbol esters. The induced levels were always greater in the late passage cell cultures than in the early passage cell cultures.
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PMID:Collagenase production by early and late passage cultures of human fibroblasts. 256 Nov 5

Comparison of the proteins secreted by early and late passage cultures of human fibroblasts reveals enhanced production of three proteins (Mr = 55,000, 58,000, and 61,000) in the late passage culture conditioned medium. The 55,000 and 58,000 Da proteins react with anticollagenase antibodies and are identified as procollagenase (Sottile, J. M. and Millis, A. J. T., J. Cell Biol. 106: 1518a, 1987). The production of immunoreactive collagenase was assayed using immunoprecipitation and immunofluorescence. Immunofluorescence microscopy revealed that each culture was heterogenous. The percentage of collagenase positive cells ranged from 1% (early passage) to 35% (late passage). Late passage cultures also secreted higher levels of immunoprecipitable collagenase into the culture medium than early passage cultures. High levels of collagenase production were also observed in fibroblasts cultured from donors with Werner's syndrome and from an aged donor. Media conditioned by the growth of human fibroblasts contained collagenase stimulating activity. In the presence of conditioned medium, the percentage of collagenase positive cells was increased to 10-20% (early passage) and 85% (late passage), indicating that each culture contains both responding and non-responding cells.
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PMID:Differential response of early and late passage fibroblasts to collagenase stimulatory factor in conditioned media. 285 Aug 87

Patients with Werner's syndrome, an autosomal recessive disorder, undergo an accelerated aging process that leads to premature death. Fibroblasts from such patients typically grow poorly in culture. Here it is shown that fibroblasts from a patient with Werner's syndrome have a markedly attenuated mitogenic response to platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF). In contrast, they have a full mitogenic response to fetal bovine serum. Both PDGF binding and receptor numbers per cell are unaltered. The Werner's syndrome cells express high constitutive levels of collagenase in vitro. Although PDGF enhances collagenase expression through increased levels of hybridizable collagenase messenger RNA in normal skin fibroblasts, no induction of collagenase occurs in the Werner's syndrome fibroblasts. Moreover, the failure to respond to this agonist effect of PDGF is not restored by fetal bovine serum. The data suggest that failure of one or more PDGF-mediated pathways in Werner's syndrome cells may contribute to the phenotypic expression of the disorder.
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PMID:Diminished response of Werner's syndrome fibroblasts to growth factors PDGF and FGF. 302 82

We describe a patient with Werner's syndrome from whom skin biopsy specimens were sampled for histology and electron microscopy and fibroblasts were cultured. Tissue sampled from five sites that varied in clinical presentation revealed striking changes in the dermoepidermal junction, elastic fibers of the papillary and reticular dermis, and adipose tissue of the hypodermis. The density and organization of the collagenous connective tissue was altered variably depending on the biopsy site. Changes noted in the epidermis were indicative of tissue regeneration and repair. Cells derived from acral areas grew poorly and could not be passed. Collagen synthesis in these cells was enhanced approximately 50%, and collagenase expression was decreased to a similar degree. Cells derived from the skin of the trunk could be passed but had an abbreviated in vitro life span. Collagen synthesis in these cells was unaltered. Serum from the patient with Werner's syndrome or from his obligate heterozygote offspring stimulated collagen synthesis in low-passage normal human skin fibroblast target cells. Sequential passage of these normal cells resulted in a blunting of the stimulatory effect. These observations suggest that a stimulator of collagen synthesis exists in the serum of patients with Werner's syndrome and that as cells (either normal or Werner's syndrome) "age" in vitro they may become hyporesponsive to this as yet undefined stimulatory factor in serum.
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PMID:Werner's syndrome. Evidence for preferential regional expression of a generalized mesenchymal cell defect. 333 48

Human diploid fibroblasts (HDFs) from newborn foreskin constitutively express interleukin-1 (IL-1) mRNA and protein after completing at least 70% (approximately 40 population doublings) of their in vitro life span. This IL-1 in turn induces the synthesis of specific proteins in aging HDFs. To determine whether IL-1 expression may be promoted by in vivo aging, we analyzed the expression of IL-1 and of inducible mRNAs in HDFs from two normal individuals 55 and 92 years old and in HDFs from a patient with premature aging caused by Werner's syndrome. By reverse transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), we detected expression of IL-1 alpha and beta mRNA and protein in early passage HDFs from both normal individuals and the Werner's syndrome patient. These HDFs also expressed the IL-1-inducible mRNAs for stromelysin, plasminogen activator inhibitor type 2, manganous superoxide dismutase, and collagenase. These results suggest that an age-dependent expression of IL-1 occurs either in vivo or after a few cell divisions in vitro. Therefore, the fibroblast phenotype is modified by the expression of IL-1-inducible genes during aging.
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PMID:Expression of interleukin-1 alpha and beta in early passage fibroblasts from aging individuals. 813 87