Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Tissue Inhibitor of Metalloproteinase-2”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

The gene for tissue inhibitor of metalloproteinases-2 is localized on human chromosome arm 17q25.

Tissue inhibitor of metalloproteinases-2 (TIMP2) is a natural inhibitor of several proteinases that are involved in the degradation of the extracellular matrix. By means of somatic cell hybrids segregating human chromosomes, the gene encoding this inhibitor was assigned to human chromosome 17. Fluorescence in situ hybridization confirmed this assignment and allowed mapping of the gene to the terminal region (17q25) of the chromosome.

Animals↗

Higher-order complex formation between the 72-kilodalton type IV collagenase and tissue inhibitor of metalloproteinases-2.

The collagenases are a class of matrix degradative enzymes whose actions are important in physiological and pathological processes. The human 72-kDa type IV collagenase (matrix metalloproteinase-2) and its proteinase inhibitor, tissue inhibitor of metalloproteinases-2 (TIMP-2), are produced as a proenzyme-inhibitor complex by numerous cell lines. We analyzed the quaternary structure of and enzyme-inhibitor interactions in the native enzyme-inhibitor complex by studying the pattern of complexes demonstrated by molecular weight determination in nondenaturing polyacrylamide gels and evaluating the products formed by reaction of the native complexes with cross-linking agents. Electrophoresis in native polyacrylamide gels demonstrates that approximately 79% of the latent enzyme is present in a 1:1 bimolecular complex with the inhibitor TIMP-2, with 21% present as a complete tetrameric complex of two molecules of collagenase combined with two molecules of TIMP-2. The enzyme complex activated with organomercurials displays a shift to a higher proportion of the bimolecular complex with only 5% present as higher molecular weight complexes. Cross-linking of the latent and active forms of the complex with bis(sulfosuccinimidyl) suberate (BS3) and bis(sulfosuccinimidyl) tartarate demonstrates both the 1:1 and 2:2 complexes as well as an intermediate form that appears to be a complex composed of two molecules of collagenase and one of TIMP-2. The distribution of cross-linked products is unchanged with the addition of excess TIMP-2 to the reaction mix, implying that the binding sites for TIMP-2 to the initial enzyme-inhibitor complex are all occupied when the stoichiometry is 1 to 1.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

Domain structure of human 72-kDa gelatinase/type IV collagenase. Characterization of proteolytic activity and identification of the tissue inhibitor of metalloproteinase-2 (TIMP-2) binding regions.

The 72-kDa gelatinase/type IV collagenase, a metalloproteinase thought to play a role in metastasis and in angiogenesis, forms a noncovalent stoichiometric complex with the tissue inhibitor of metalloproteinase-2 (TIMP-2), a potent inhibitor of enzyme activity. To define the regions of the 72-kDa gelatinase responsible for TIMP-2 binding, a series of NH2- and COOH-terminal deletions of the enzyme were constructed using the polymerase chain reaction technique. The full-length and the truncated enzymes were expressed in a recombinant vaccinia virus mammalian cell expression system (Vac/T7). Two truncated enzymes ending at residues 425 (delta 426-631) and 454 (delta 455-631) were purified. Like the full-length recombinant 72-kDa gelatinase, both COOH-terminally truncated enzymes were activated with organomercurial and digested gelatin and native collagen type IV. In contrast to the full-length enzyme, delta 426-631 and delta 455-631 enzymes were less sensitive to TIMP-2 inhibition requiring 10 mol of TIMP-2/mol of enzyme to achieve maximal inhibition of enzymatic activity. The activated but not the latent forms of the delta 426-631 and delta 455-631 proteins formed a complex with TIMP-2 only when excess molar concentrations of inhibitor were used. We also expressed the 205-amino acid COOH-terminal fragment, delta 1-426, and found that it binds TIMP-2. In addition, a truncated version of the 72-kDa gelatinase lacking the NH2-terminal 78 amino acids (delta 1-78) of the proenzyme retained the ability to bind TIMP-2. These studies demonstrate that 72-kDa gelatinases lacking the COOH-terminal domain retain full enzymatic activity but acquire a reduced sensitivity to TIMP-2 inhibition. These data suggest that both the active site and the COOH-terminal tail of the 72-kDa gelatinase independently and cooperatively participate in TIMP-2 binding.

Base Sequence↗

Tissue inhibitor of metalloproteinase-2 (TIMP-2) has erythroid-potentiating activity.

Tissue inhibitor of metalloproteinase (TIMP) was purified and molecularly cloned on the basis of its erythroid-potentiating activity (EPA). TIMP/EPA appears to be a bifunctional molecule with both growth factor and anti-enzymatic activity. Recently, a second TIMP-related molecule was identified and we have investigated its possible erythroid-potentiating activity. Native, purified human TIMP-2 was assayed for erythroid-potentiating activity using an in vitro erythroid burst formation assay and was compared with that of previously characterized recombinant EPA/TIMP-1. The results demonstrate that both members of the tissue inhibitor of metalloproteinase family, TIMP-1 and TIMP-2, possessed erythroid potentiating activity which was inhibited by antibodies developed to neutralize EPA. These results suggest that TIMP-2 shares a common structural domain with EPA/TIMP-1 that is responsible for the erythroid-potentiating activity of these inhibitors. Therefore, TIMP-1 and TIMP-2, with both anti-protease activity and growth factor activity, join a family of bifunctional molecules such as fibroblast growth factor and thrombin which have both enzymatic and growth factor activity.

Carrier Proteins↗

A one-step sandwich enzyme immunoassay for human matrix metalloproteinase 3 (stromelysin-1) using monoclonal antibodies.

A one-step sandwich enzyme immunoassay (EIA) for matrix metalloproteinase 3 (MMP-3; stromelysin-1) was developed. The assay system used two simultaneous immunoreactions using a solid phase monoclonal antibody and a horseradish peroxidase-labeled monoclonal antibody (Fab'). The sensitivity of the assay system was 20 micrograms/l and linearity was obtained between 31 and 500 micrograms/l. The EIA system was capable of measuring both precursor and active forms of MMP-3 as well as the forms of MMP-3 complexed with tissue inhibitors of metalloproteinases. MMP-3 levels as measured by this assay are significantly higher in the sera of patients with rheumatoid arthritis as compared to those of healthy subjects and patients with osteoarthritis. Immunoblot analyses showed that in the sera and synovial fluids of patients with rheumatoid arthritis, MMP-3 is present in the 59- and 57-kDa precursor forms.

Animals↗

Expression of metalloproteinases and their inhibitors in primary pulmonary carcinomas.

Nine primary pulmonary carcinomas, one metastatic carcinoma, and two malignant pleural mesotheliomas have been analysed for the expression at the mRNA level of metalloproteinases (MPs) and tissue inhibitors of MPs (TIMPs). In situ hybridisation showed TIMP-1 and TIMP-2 transcripts predominantly over tumour stroma and gelatinases evenly distributed over both stromal and tumour cells. While both TIMP-1 and TIMP-2 were expressed in non-neoplastic lungs (NNL) as well as in carcinomas, stromelysin 3 (ST3), 92 kDa gelatinase and interstitial collagenase were expressed only by carcinomas. Expression of these MPs by carcinomas was independent of histologic type and such tumour features as fibrosis or necrosis. The consistent expression of ST3 by all of the carcinomas examined and absence of its expression in NNL indicates that ST3 production is likely associated with the malignant phenotype. However, since 92 kDa gelatinase and interstitial collagenase transcripts were found in some but not all tumour samples, their expression is not a uniform feature of pulmonary carcinomas. The possible prognostic significance of the expression of the latter two enzymes by carcinomas remains to be established.

Aged↗

The C-terminal domain of 72 kDa gelatinase A is not required for catalysis, but is essential for membrane activation and modulates interactions with tissue inhibitors of metalloproteinases.

Recombinant 72 kDa gelatinase A and a truncated form lacking the C-terminal domain were shown to be activated by organomercurials and to possess similar activities towards a number of substrates. The truncated proenzyme differed from the full-length gelatinase in that it could not be activated by a membrane activator and did not bind tissue inhibitor of metalloproteinase (TIMP)-2. Kinetic studies also showed that the inhibition of the activated truncated enzyme, by both TIMP-1 and TIMP-2, was considerably decreased compared with the full-length enzyme. We conclude that the C-terminal domain plays an important role in the regulation of gelatinase A by a potential physiological activator and inhibitors.

Base Sequence↗

Progesterone regulates the activity of collagenase and related gelatinases A and B in human endometrial explants.

Explants of human endometrium were cultured to study the release of matrix metalloproteinases (MMPs). Analysis of conditioned media by zymography revealed latent and active forms of collagenase (MMP-1, EC 3.4.24.7), 72-kDa gelatinase A (MMP-2, EC 3.4.24.24), and 92-kDa gelatinase B (MMP-9, EC 3.4.24.35). These proteinases were identified by their M(r), their inhibition by tissue inhibitor of metalloproteinases, and the activation of their zymogens by trypsin or aminophenylmercuric acetate. In the absence of sex hormone, explants released large amounts of enzyme activities, as measured by densitometry of zymograms or in soluble assays. Physiological concentrations of progesterone (10-200 nM) almost totally abolished the release of collagenase, of total gelatinase activity, and of the active form of gelatinase B and largely inhibited the release of the active form of gelatinase A. These effects, which were antagonized by mifepristone (RU 38486), suggest that progesterone restrains endometrial tissue breakdown by blocking the secretion and activation of MMPs.

Collagenases↗

Characterization of metalloproteinases and tissue inhibitors of metalloproteinases in human plasma.

In this study, we have identified and characterized metalloproteinases and tissue inhibitors of metalloproteinases (TIMPs) in human plasma. Treatment of plasma with trypsin or aminophenylmercuric acetate resulted in activation of latent gelatinolytic activity. Fractionation of plasma by gelatin Sepharose chromatography resulted in the isolation of 72 kDa and 92 kDa gelatinases/type IV collagenases. The 72 kDa gelatinase was purified by gel filtration chromatography. Stromelysin-1 was isolated from plasma by Matrex green A affinity chromatography. Immunoblotting of plasma fractions with antibodies to unique peptide regions of human gelatinases differentiated the 72 kDa gelatinase from the 92 kDa gelatinase. Antibodies to the amino terminal peptides of each enzyme were used to determine that plasma gelatinases circulate as latent proenzymes. Immunoblotting with antibodies directed against human stromelysin identified a 57 kDa stromelysin. TIMP-1 (28 kDa) and TIMP-2 (21 kDa) were also identified by immunoblotting of gelatin Sepharose bound plasma proteins using non-crossreacting antibodies to each protein.

Amino Acid Sequence↗

Effect of phorbol ester and cytokines on matrix metalloproteinase and tissue inhibitor of metalloproteinase expression in tumor and normal cell lines.

The effect of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) and the cytokines interleukin-1 (IL-1) and tumor necrosis factor-alpha (TNF-alpha) on matrix metalloproteinases (MMP) and metalloproteinase inhibitors was studied in a variety of human cell lines. Expression of the mammalian collagenase (MMP-1), 72-kD gelatinase/type IV collagenase (MMP-2), stromelysin (MMP-3), 92-kD gelatinase/type IV collagenase (MMP-9), and tissue inhibitors of metalloproteinases (TIMP-1 and TIMP-2) was assessed by zymography and Northern blot analysis. MMP-2 and TIMP-2 activities were refractory to TPA, IL-1 and TNF-alpha treatment in most of the cell lines. In contrast, MMP-3, MMP-9 and TIMP-1 activities were markedly stimulated by TPA in most of the tumor cell lines and human umbilical vein endothelial cells (HUVEC), whereas the fibroblast lines were minimally stimulated or unresponsive to TPA. The MMP-3, MMP-9 and TIMP-1 stimulation in response to IL-1 and TNF-alpha treatment was detected in some of the tumor cell lines and HUVEC. The increase in activity was less marked than in TPA. A breast carcinoma cell line, MDA-MB-231, which did not express MMP-2, had high expression of MMP-3 and MMP-9 which were unaffected by TPA and cytokine treatment. Northern blot analysis of MMP and TIMP mRNA expression reflected the zymogram findings for most of the cell lines. TPA-mediated stimulation of MMP-1 was similar to that of MMP-3 and MMP-9. Exceptions were the fibroblast cell lines which showed either a much more marked mRNA response of MMP-9 to TPA than observed at protein level, or a high constitutive MMP-9 mRNA when MMP-9 activity was not detectable by zymography. TPA-mediated stimulation of MMP-9 and TIMP-1 activity was blocked by staurosporine, an inhibitor of protein kinase C (PKC). A non-PKC-activating phorbol ester, 4 alpha-phorbol-12,13-didecanoate, did not stimulate MMP-9 and TIMP-1 activity. TPA treatment caused the increased expression of c-fos containing AP-1-specific binding activity in selected tumor cell lines. This activity was maximal at 6 h. An association was observed between AP-1 binding activity and increased expression of MMP-1, MMP-3 and MMP-9, which possess TPA-responsive elements (TRE). TPA-sensitive MMPs and TIMP-1 were variably stimulated by biologically relevant cytokines, such as IL-1 and TNF-alpha.(ABSTRACT TRUNCATED AT 400 WORDS)

Base Sequence↗

Interaction of 92-kDa type IV collagenase with the tissue inhibitor of metalloproteinases prevents dimerization, complex formation with interstitial collagenase, and activation of the proenzyme with stromelysin.

Secreted metalloproteases initiating proteolytic degradation of collagens and proteoglycans play a critical role in remodeling of the connective tissue. Activation of the secreted proenzymes and interaction with their specific inhibitors TIMP and TIMP-2 are responsible for regulation of enzyme activity in extracellular space. We have previously demonstrated that 92- and 72-kDa Type IV procollagenases, in contrast to interstitial collagenase (ClI), form specific complexes with TIMP and the related inhibitor TIMP-2, respectively. The physiologic significance of the proenzyme-inhibitor complex and the mechanism of activation of Type IV collagenases remained unclear. Here, we demonstrate that in the absence of TIMP, 92-kDa Type IV procollagenase (92T4Cl) can form a covalent homodimer and a novel complex with ClI. In the presence of TIMP, the formation of a 92T4Cl proenzyme complex with TIMP prevents dimerization, formation of the complex with ClI, and activation of the 92T4Cl proenzyme by stromelysin, a related metalloprotease. The proenzyme homodimer is unable to form a complex with TIMP. All TIMP-free forms of the proenzyme can be activated by stromelysin. The 92T4Cl-ClI complex can be activated to yield a complex active against both gelatin and fibrillar Type I collagen, suggesting a mechanism for cooperative action of two enzymes in reducing collagen fibrils to small peptides under physiologic conditions.

Cell Line↗

Mosaic structure of the secreted ECM metalloproteases and interaction of the type IV collagenases with inhibitors.

SV-40 transformed human lung fibroblasts and HT 1080 fibrosarcoma cells secrete a 92-kDa type IV collagenase (in addition to 72-kDa type IV collagenase identical to that found in macrophages, phorbol ester differentiated U937 cells, and keratinocytes. The expression of this protease is induced by the tumor promoter TPA, and interleukin-1 and was not detected in the parental human lung fibroblast. The 92-kDa preproenzyme has a predicted Mr of 78,426, including a 19 amino acid long hydrophobic signal peptide. The apparent discrepancy between the predicted molecular weight and the molecular weight of the secreted protein is due to a post-translational modification of the enzyme through glycosylation. The 92-kDa type IV collagenase consists of five distinct domains, including a unique 54 amino acid long collagen--like domain, and is a member of the secreted ECM metalloprotease gene family. Both the 72 and 92-kDa type IV collagenase contain a fibronectin-like collagen binding domain. The mosaic structure of the secreted ECM metalloproteases is a result of a recruitment of the functional units from ECM structural macromolecules into an enzyme protein in the process of evolution. The 92-kDa and 72-kDa type IV collagenase proenzymes form a noncovalent complex with inhibitors, which is activatable by APMA, yielding an enzymes with similar if not identical substrate specificity profile. Our results demonstrate that while the 92-kDa type IV collagenase forms a stoichiometric complex with TIMP, the 72-kDa type IV collagenase, purified from the same starting material, contains a novel 24-kDa inhibitor-TIMP-2.

Amino Acid Sequence↗

Secreted inhibitors of metalloproteinases (IMPs) that are distinct from TIMP.

The tissue inhibitor of metalloproteinases (TIMP, M(r) 30,000) is secreted by many cell and tissue types and has been shown to inhibit most secreted mammalian metalloproteinases. In matrix and tissue invasion assays, the inactivation or removal of TIMP enhances invasiveness. However, many of the cells that secrete TIMP also secrete other metalloproteinase inhibitors. By analysis of medium conditioned by various endothelial, mesenchymal, and neural cells on SDS-.substrate-polyacrylamide-inhibitor gels (reverse zymograms), we have detected at least three other distinct inhibitors of metalloproteinases (IMPs). Some or all of these IMPs have been detected in secretions of mouse, rabbit, sheep, and human cells and are all smaller in apparent molecular size than TIMP (IMP-1, M(r) 26,000; IMP-2, M(r) 21,000; IMP-3, M(r) 18,000). These IMPs are not proteolytic degradation products of TIMP nor do they represent nonglycosylated TIMP. The IMPs do not cross-react in the native or denatured state with any of several anti-TIMP antibodies. The IMPs appear to be regulated independently of each other and of TIMP. In vitro, the complex consisting of one of the IMPs, or TIMP, and a metalloproteinase can be dissociated into functional inhibitor and metalloproteinase. Whether this characteristic is significant in vivo is not known. IMP-2 has been purified from several sources and shares sequence homology with TIMP, suggesting that the IMPs and TIMP may constitute a gene family. The most significant characteristic of IMP-2 is that it appears to preferentially inhibit, on a mole:mole basis, the M(r) 68,000 gelatinase rather than collagenase or stromelysin.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

TIMP-2: identification and characterization of a new member of the metalloproteinase inhibitor family.

Human melanoma cells secrete a 21 kDa protein which binds with 1:1 molar stoichiometry to the matrix metalloproteinase type IV collagenase proenzyme (70 kDa gelatinase) secreted by the same cells. We have purified this binding protein and determined its complete primary structure by directly sequencing overlapping peptide fragments which span the entire protein. We refer to this protein as CSC-21K based on the amino-terminal amino acids CSC and the apparent molecular weight of 21,000 daltons on gel electrophoresis. The amino acid sequence of CSC-21K demonstrates that this protein shares significant homology with human TIMP (tissue inhibitor of metalloproteinase), including conservation of the positions of the twelve cysteine residues and three of four tryptophan residues. The identification of CSC-21K now indicates that a family of TIMP-related proteins exists. Individual members of this family may possess selective affinities for different members of the matrix metalloproteinase family. Based on its sequence homology to TIMP and ability to inhibit type IV collagenolysis we propose the name TIMP-2 for this inhibitor. TIMP-2 produced by tumor cells can also be considered as an onco-suppressor gene product, because it could play an important role in regulating the metalloproteinases involved in tumor invasion and angiogenesis.

Amino Acid Sequence↗

TIMP-2 reduces proteolytic opening of blood-brain barrier by type IV collagenase.

Intracerebral hemorrhage occurs in tumors, stroke and head trauma. Proteolysis of the extracellular matrix around cerebral capillaries by naturally occurring mammalian 72-kDa type IV collagenase may initiate this pathologic event. To investigate this hypothesis adult rats underwent intracerebral injection of type IV collagenase purified from human melanoma cells. Histologically, at 4 h there was perivascular cellular infiltration with hemorrhage, and by 24 h there was infarction with necrosis, edema and hemorrhage. Ultrastructurally, the basal lamina of endothelial cells was disrupted at 2 h. Brain uptake of [14C]dextran and [3H]sucrose increased after intracerebral injection of type IV collagenase compared to controls (P less than 0.0001). Tissue inhibitor of metalloproteinase-2 (TIMP-2) reduced the tracer uptake (P less than 0.02). Metalloproteinase inhibitors reduce extracellular matrix proteolysis and protect the blood-brain barrier.

Analysis of Variance↗

Diurnal differences in the effects of heat exposure on renal function: A randomized controlled crossover trial.

High temperature is a major risk factor for kidney injury, and population exposure to nighttime heat is increasing as the climate warms. However, whether renal responses to heat exposure differ between daytime and nighttime remains unclear. Forty-one healthy adults participated in a randomized crossover experiment conducted in a controlled laboratory setting. Participants were exposed to heat (32°C during daytime; 30°C during nighttime) and thermoneutral conditions (26°C) for 8 h. Blood and urine samples were collected before and after each exposure to examine various renal biomarkers reflecting glomerular filtration function, tubular injury, and early kidney stress. Heat exposure affected both blood and urinary biomarkers of kidney function, with notable diurnal differences in renal responses. Daytime heat exposure primarily affected blood markers of glomerular filtration, increasing creatinine by 7.67% (95% CI: 4.73%-10.61%) and cystatin C by 3.05% (95% CI: 0.17%-5.93%), while reducing estimated glomerular filtration rate by 0.05% (95% CI: 0.02%-0.08%). In contrast, nighttime heat exposure predominantly elevated urinary biomarkers of early kidney stress, including insulin-like growth factor-binding protein 7 (58.40%, 95% CI: 27.66%-89.14%), kidney injury molecule-1 (47.25%, 95% CI: 18.91%-75.59%), and tissue inhibitor of metalloproteinases-2 (51.88%, 95% CI: 22.26%-81.51%). Moreover, increases in insulin-like growth factor-binding protein 7 were significantly greater at night than during the day. Sleep-related parameters, including sleep quality, duration, and heart rate variability, partially mediated nighttime heat effects on renal responses. These results indicated that heat exposure induced different diurnal patterns in renal responses.

Humans↗