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Presence of matrix metalloproteinases and tissue inhibitor of matrix metalloproteinase in human sperm.

The matrix metalloproteinases (MMPs) are a family of proteolytic enzymes that degrade protein components of the extra-cellular matrix. The necessity of breakdown of physical barriers in the fertilization process suggests that MMPs, along with their tissue inhibitors (TIMPs), might be involved in this task. We have examined the presence of MMP and TIMP in normal and abnormal human sperm samples by gel zymography and Western blot analysis. Thirty-five normal sperm samples and 35 abnormal sperm samples were examined in this study. Gel zymography showed 92-, 72-, 62-, and 28-kd molecular-weight bands exhibiting gelatin-degrading activity in both normal and abnormal sperm samples. The 92-, 72-, and 62-kd bands with gelatinolytic activity are consistent with pro-MMP-9, pro-MMP-2, and active MMP-2, respectively (pro-MMP being the zymogen of MMP). Western blot analysis showed the presence of TIMP-1 in both normal and abnormal sperm samples. A higher 28-kd activity and a lower 92-kd MMP activity in normal sperm samples relative to abnormal samples were detected. No marked difference in TIMP-1, 72-kd, and 62-kd release was observed between normal and abnormal sperm samples. In conclusion, this is the first report of MMP activity in normal and abnormal human sperm samples and of TIMP presence in sperm samples. The data indicate a different MMP profile between normal and abnormal sperm samples, with a higher 28-kd activity and a lower 92-kd MMP activity in normal relative to abnormal samples.

Humans↗

[Expression of mRNA of matrix metalloproteinase and tissue inhibitor of matrix metalloproteinase after cardiopulmonary resuscitation for asphyxial cardiac arrest in rat].

OBJECTIVE: To study the change in mRNA expression of matrix metalloproteinase (MMPs) and tissue inhibitor-1 of matrix metalloproteinase (TIMP-1) in brain after cardiopulmonary resuscitation (CPR) for asphyxial cardiac arrest in rat. METHODS: The animal model of cardiac arrest was reproduced by clamping endotracheal tube at the expiration. Eighty male SD rats were randomly divided into two groups: control group and resuscitation group, and they were again divided into 0, 0.5, 3, 6, 9 hours subgroups (n=8). Evans blue content and mRNA expressions of MMPs and TIMP-1 in the brain after CPR were determined respectively. RESULTS: The mRNA expression of MMP-9 and TIMP-1 was up-regulated 3 hours after restoration of spontaneous circulation (ROSC). At 6 hours after ROSC, they were markedly high, and the ratio of MMP-9/TIMP-1 was higher too. The mRNA expression of MMP-2 showed no significant change at 9 hours after ROSC. CONCLUSION: The mRNA expression of MMP-9 and TIMP-1 and MMP-9/TIMP-1 are increased at early stage after CPR, but the mRNA expression of MMP-2 shows no significant change.

Animals↗

Differential expression of matrix metalloproteinase and tissue inhibitor of matrix metalloproteinase genes in the mouse central nervous system in normal and inflammatory states.

Matrix metalloproteinases (MMPs) are implicated in the pathogenesis of inflammatory disorders of the central nervous system (CNS) whereas the contribution of the major endogenous counter-regulators of MMPs, the tissue inhibitors of the matrix metalloproteinases (TIMPs), is unclear. We investigated the temporal and spatial expression patterns in the CNS of nine MMP genes and three TIMP genes in normal mice, in mice with EAE, and in transgenic mice with astrocyte (glial fibrillary acidic protein)-targeted expression of the cytokines interleukin-3 (macrophage/microglial demyelinating disease), interleukin-6 (neurodegenerative disease), or tumor necrosis factor-alpha (lymphocytic encephalomyelitis). In normal mice, the MMPs MT1-MMP, stromelysin 3, and gelatinase B were expressed at low levels, whereas high expression of TIMP-2 and TIMP-3 was observed predominantly in neurons and in the choroid plexus, respectively. In EAE and the transgenic mice, significant induction or up-regulation of various MMP genes was observed, the pattern of which was somewhat specific for each of the models, and there was significant induction of TIMP-1. In situ localization experiments revealed a dichotomy between MMP expression that was restricted to leukocytes and possibly microglia within inflammatory lesions and TIMP-1 expression that was observed in activated astrocytes circumscribing the lesions. These findings demonstrate specific spatial and temporal regulation in the expression of individual MMP and TIMP genes in the CNS in normal and inflammatory states. The distinct localization of TIMP-1 and MMP expression during CNS inflammation suggests a dynamic state in which the interplay between these gene products may determine both the size and resolution of the destructive inflammatory focus.

Animals↗

The effect of IL-1beta on the expression of matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases in human chondrocytes.

Interleukin-1 (IL-1) plays key roles in altering cartilage matrix turnover. This turnover is regulated by matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs). In the present study, we examined the effect of IL-1beta on cell proliferation, alkaline phosphatase (ALPase) activity, and the expression of MMPs, and TIMPs in chondrocytes derived from normal human femoral cartilage. The cells were cultured in Dulbecco's modified Eagle's medium containing 15% fetal bovine serum and 0, 1, 10, or 100 U/ml of IL-1beta for up to 28 days. The level of expression of MMPs and TIMPs was estimated by determining mRNA levels using real-time PCR and by determining protein levels using an enzyme-linked immunosorbent assay. Cell proliferation decreased in the presence of IL-1beta after day 21 of culture. ALPase activity decreased significantly in the presence of IL-1beta after day 10 of culture. The expression of MMP-1, -2, and -3 increased markedly in the presence of IL-1beta after day 21 of culture. MMP-13 expression increased markedly in the presence of IL-1beta on day 1 of culture, but decreased markedly after day 7. The expression of TIMP-1 increased significantly after day 14 of culture. The expression of TIMP-2 decreased significantly on day 1, but increased significantly from day 3 to day 14 of culture. These results suggest that IL-1beta may stimulate cartilage matrix turnover by increasing mainly MMP-13 production by the cells.

Cartilage↗

Matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases in the human lens: implications for cortical cataract formation.

PURPOSE: To characterize the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs) in human cortical cataract and to determine whether there is a correlation with the localization of cortical cataract. To evaluate the expression and activity of MMPs and TIMPs after cytokine and UV-B exposure in a human lens epithelial cell line. METHODS: Twenty-eight human donor eyes with cortical cataract and 21 normal human donor eyes were photographed. Thirteen cortical cataract and six normal lenses were immunohistochemically analyzed for MMP-1, -2, -3, and -9 and TIMP-1, -2, and -3. Twelve fresh cortical cataract and 12 normal lenses were divided into quadrants to quantify, by ELISA, the expression of MMP-1, -2, -3, and -9 and TIMP-1. Three fresh cortical cataract and three control lenses were assessed for MMP-1, -2, and -9 activity by SDS-PAGE zymography. Human lens epithelial cells (HLE-SRA-01/04) were exposed to proinflammatory cytokines and UV-B radiation to determine the protein expression profiles of MMP-1, -2, -3, and -9 and TIMP-1 and -2. RESULTS: Immunohistochemical analysis revealed specific localization of MMP-1 within lens epithelium and cortical lens fibers of cortical cataract. Normal lenses had equally low MMP-1, -2, -3, and -9 and TIMP-1, -2, and -3 immunoreactivity, expression, and activity in all lens quadrants. IL-1 and TNF-alpha upregulated the expression of MMP-2, -3, and -9, and UV-B upregulated the expression of MMP-1 in the SRA-01/04 HLE cell line. CONCLUSIONS: This is the first study to localize the expression of MMP-1 in cataracts with clinically observed opacification in vivo and to examine the expression induced by UV-B, in vitro.

Adult↗

Matrix metalloproteinase and tissue inhibitor of matrix metalloproteinase expression in human preimplantation embryos.

OBJECTIVE: To examine human embryos at various stages of preimplantation development for simultaneous expression of matrix metalloproteinases (MMPs) and tissue inhibitor of matrix metalloproteinases (TIMPs). DESIGN: mRNAs of specific MMPs and TIMPs were examined in single human embryos, at different stages of preimplantation development, by reverse transcription-polymerase chain reaction (RT-PCR). Single embryo immunohistochemistry was applied to examine the protein expression. SETTING: University-affiliated IVF-ET program. PATIENT(S): Couples, attending the university-affiliated IVF-ET program, electing to donate poor prognosis embryos with anomalous morphology. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The expression of MMP-1, MMP-2, MMP-9, TIMP-1, TIMP-2, and TIMP-3 in preimplantation embryos. RESULT(S): The MMP-2 mRNA was expressed consistently during development from one-cell to blastocyst stage. The TIMP-1 and TIMP-3 mRNAs were detected in embryos at all stages; however, in the later preimplantation developmental stages, an increasing proportion of embryos expressing TIMP-1 and TIMP-3 mRNA were noted. The MMP-1, MMP-9, and TIMP-2 mRNAs were detected in only a minority of human embryos studied. Immunohistochemistry showed MMP-1 and TIMP-1 protein expression in preimplantation embryos. CONCLUSION(S): The existence of MMP and TIMP mRNA expression in human preimplantation embryos argues for a role for these metalloproteinases and their inhibitors during the process of implantation in humans.

Blastocyst↗

Matrix metalloproteinase activity and immunohistochemical profile of matrix metalloproteinase-2 and -9 and tissue inhibitor of metalloproteinase-1 during human dermal wound healing.

Proteolytic activity is required for the turnover of the extracellular matrix during wound healing. Matrix metalloproteinases can collectively cleave all components of the extracellular matrix, with the endogenous tissue inhibitor of metalloproteinase-1 regulating their activity. Breast tissue taken at varying postoperative times (n= 92) or during surgery (controls, n= 17), was used to investigate the temporal and spatial activity of matrix metalloproteinase-2 and -9 and tissue inhibitor of metalloproteinase-1 during human wound healing. Matrix metalloproteinase activity, determined using a quenched fluorescence substrate assay, increased during early healing (3-8 weeks) compared to controls, and then decreased between 24 and 36 weeks after surgery (p < 0.05 until 24 weeks, Mann-Whitney U-test). Immunohistochemistry scores for matrix metalloproteinase-9 expression were significantly elevated compared to controls in scar endothelial cells and fibroblasts from 2 until 12 and 20 weeks, respectively. Matrix metalloproteinase-2 staining was observed exclusively in fibroblasts, reaching maximum levels 8-12 weeks after surgery, decreasing by 1.5 years but remaining significantly increased. Tissue inhibitor of metalloproteinase-1 staining was relatively sparse but was significantly increased until 8 weeks after surgery. These results show that matrix metalloproteinases are present at elevated levels during early wound healing, when angiogenesis occurs, and suggest that matrix metalloproteinase-9 may play a significant role. The later expression of matrix metalloproteinase-2 and -9 in fibroblasts suggests a role in extracellular matrix remodeling.

Adult↗

Matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases mRNA transcripts in the bronchial secretions of asthmatics.

Asthma is a chronic inflammatory disease characterized by profound extracellular matrix changes referred to as bronchial remodelling. In this study, we evaluated matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) mRNA expression in bronchial secretions of asthmatics and correlated MMPs modulations with the lung function as a reflection of the bronchial extracellular matrix remodelling. Quantitative RT-PCR was performed on cell pellets obtained from induced sputum in order to detect the mRNAs for MMP-1, -2, -3, -8, -9, -12, -13 TIMP-1, -2, while semiquantitative RT-PCR was performed to assess the expression of MMP-7, monocyte chemoattractant protein-1 (MCP-1) and transforming growth factor-beta(1) (TGF-beta(1)). The mRNA transcripts for MMP-1, TIMP-1 and monocyte chemoattractant protein-1 (MCP-1) were increased in cell pellets of induced sputum from asthmatics when compared to controls (P<0.05), and the intensity of MMP-1 mRNA expression inversely correlated with the FEV(1) in asthmatics (r=-0.49, P<0.05). The MMP-1 mRNA/TIMP-1 mRNA ratio correlated with the levels of MCP-1 mRNA in asthmatics (r=0.47, P<0.05). There were no differences between the groups with respect to mRNA coding for MMP-2, -3, -7, -8, -9, -12, -13, -14, TIMP-2 and TGF-beta(1). We conclude that cells contained in the bronchial secretions from asthmatics express higher amounts of mRNA for MMP-1 and TIMP-1, perhaps related to an increased expression of MCP-1, which might contribute to the extracellular matrix changes observed during airway remodelling.

Adolescent↗

Complexities in ETS-domain transcription factor function and regulation: lessons from the TCF (ternary complex factor) subfamily. The Colworth Medal Lecture.

The ETS-domain transcription factor family can be divided into a series of subfamilies. Elk-1 represents the founding member of the ternary complex factor (TCF) subfamily. By focusing on the TCF subfamily, we can demonstrate the complexities that exist in the function and regulation of ETS-domain transcription factors. This article focuses on Elk-1 in detail and summarizes the functions of other TCFs. The key themes covered include the domain structure of the TCFs, the mechanisms of complex formation with serum response factor, regulation of TCFs by mitogen-activated protein kinase cascades, and transcriptional regulatory properties of the TCFs. Finally, the emerging role of the TCFs in vivo is discussed. A picture is developing indicating that, while these proteins exhibit significant sequence and functional conservation, key differences in their structure and regulation are being identified which may relate to unique functions of these proteins in vivo.

Amino Acid Sequence↗

[Clinical significance of matrix metalloproteinase-9/tissue inhibitors of matrix metalloproteinase -1 imbalance in maternal serum, amniotic fluid, umbilical cord serum in patients with premature rupture of the membranes].

OBJECTIVE: To investigate the roles of matrix metalloproteinase (MMP)-9 and tissue inhibitors of matrix metalloproteinase (TIMP)-1 in maternal serum, amniotic fluid and umbilical cord serum in predicting premature rupture of the membranes (PROM) and chorioamnionitis. METHODS: The levels of MMP-9 and TIMP-1 were detected by enzyme linked immunosorbent assay in maternal serum, amniotic fluid, umbilical cord serum of 58 pregnant women with PROM and 38 women with normal pregnancies. Chorioamnionitis was histopathologically confirmed after delivery. RESULTS: (1) The levels of MMP-9 in maternal serum, umbilical cord serum and amniotic fluid were (141.9 +/- 84.6) ng/L, (138.2 +/- 81.4) ng/L and (85.6 +/- 27.5) ng/L respectively, significantly higher in patients with PROM than those of the control group (P < 0.05, P < 0.05 and P < 0.01 respectively), while the levels of TIMP-1 in maternal serum, amniotic fluid and umbilical cord serum were (378.1 +/- 220.2) ng/L, (44.6 +/- 24.0) ng/L and (257.2 +/- 98.8) ng/L respectively, significantly lower in patients with PROM than those of the control group (P < 0.05, P < 0.05 and P < 0.01 respectively). (2) The longer the duration from rupture of membranes to delivery was, the more serious chorioamnionitis was, and the higher the levels of MMP-9 and the lower the TIMP-1 levels in maternal serum, amniotic fluid, and umbilical cord serum were. (3) The levels of MMP-9 in maternal serum, umbilical cord serum and amniotic fluid were (183.8 +/- 84.7) ng/L, (171.2 +/- 92.9) ng/L and (95.5 +/- 21.1) ng/L respectively, significantly higher in patients with chorioamnionitis than those of non-chorioamnionitis (P < 0.05, P < 0.05 and P < 0.01 respectively), while the levels of TIMP-1 in maternal serum, amniotic fluid and umbilical cord serum were (269.7 +/- 144.4) ng/L, (32.1 +/- 16.6) ng/L and (210.6 +/- 81.9) ng/L respectively, significantly lower in patients with chorioamnionitis than those of non-chorioamnionitis (P < 0.05, P < 0.05 and P < 0.01 respectively). (4) The levels of MMP-9 in maternal serum, umbilical cord serum and amniotic fluid were (234.4 +/- 79.4) ng/L, (222.1 +/- 120.1) ng/L and (108.5 +/- 42.2) ng/L respectively, significantly higher in neonates whose Apgar score < or = 7 than those of neonates whose Apgar score > or = 8 (P < 0.05, P < 0.05 and P < 0.01 respectively), while the levels of TIMP-1 in maternal serum, amniotic fluid and umbilical cord serum were (225.3 +/- 121.7) ng/L, (25.2 +/- 15.8) and (181.7 +/- 135.2) ng/L respectively, significantly lower in neonates whose Apgar score < or = 7 than those of neonates whose Apgar score > or = 8 (P < 0.05, P < 0.05 and P < 0.01 respectively). CONCLUSIONS: It is suggested that preterm PROM is associated with increased MMP-9 and decreased TIMP-1 levels. MMP-9 and TIMP-1 are valuable clinical biological markers for identifying chorioamnionitis and predicting neonates prognosis.

Adult↗

[Expression of epidermal growth factor receptor, ErbB2 and matrix metalloproteinase-9 in hepatolithiasis and cholangiocarcinoma].

BACKGROUND/AIMS: Hepatolithiasis is a common disease in East Asia and presents as a histological feature of proliferative glands containing mucin. 5-10% of hepatolithiasis is known to be associated with cholangiocarcinoma. Recent studies reported that epidermal growth factor receptor (EGFR) could be activated through heparin binding- EGF cleavage by metalloproteinases. Matrix metalloproteinases (MMPs) which digest the extracellular matrix are required for cancer cell invasion and the expression of MMP-9 is known to be increased in cholangiocarcinoma. However, there has been few studies on the expressions and roles of EGFR and MMP in hepatolithiasis. This study was performed to clarify and compare the expressions of EGFR, erbB2 and MMP-9 in hepatolithiasis and cholangiocarcinoma. METHODS: Surgically resected liver tissues with hepatolithiasis (n = 14), cholangiocarcinoma (n = 20) and trauma (n = 2 as controls) were included. The expressions of EGFR, erbB2 and MMP-9 in tissue samples were examined by immunohistochemistry using respective monoclonal antibodies. RESULTS: In traumatic livers, the expressions of EGFR, erbB2 and MMP-9 were all negative. The expression of EGFR was increased in hepatolithiasis group (79%, 11/14) compared with cholangiocarcinoma group (25%, 5/20) (p < 0.05). The expression of erbB2 was detected only in cholangiocarcinoma (25%, 5/20). MMP-9 was increased in both hepatolithiasis (79%, 11/14) and cholangiocarcinoma (95%, 19/20) (p > 0.05). CONCLUSIONS: EGFR expression appears to be the dominant component in periductular hyperplasia of hepatolithiasis and MMP-9 is upregulated not only in cholangiocarcinoma but also in hepatolithiasis. This study suggests that EGFR and MMP-9 are associated with cholangiocarcinoma and hepatolithiasis.

Adult↗

Expression of matrix metalloproteinases and tissue inhibitor of matrix metalloproteinases in mesothelial cells and their regulation by transforming growth factor-beta1.

Tissue injury and pelvic inflammation often results in peritoneal scar tissue formation. The objective of this study was to determine whether mesothelial cells which line the peritoneal cavity express matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs), and if their expression is regulated by transforming growth factor-beta1, a key regulator of tissue fibrosis. For this purpose we used Met-5A cells, a cell line derived from human normal mesothelial cells, and for comparative analysis we used U-937 cells, a human monocytic/macrophage cell line. The cells were treated with transforming growth factor-beta1 (1 ng/ml) for various time periods and the levels of MMP and TIMP mRNA and protein expression were determined using quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. The results indicate that the mesothelial cells and macrophages express MMP-1 (collagenase-1), MMP-3 (stromelysin-1), TIMP-1 and TIMP-2 mRNA and protein at various levels, with significantly higher TIMPs than MMPs, and higher MMP-1 than MMP-3 (p < 0.001). The mesothelial cells express significantly less MMP-1, higher MMP- 3 and similar levels of TIMP mRNA compared to macrophages. In a time-dependent manner, treatment of the mesothelial cells with transforming growth factor-beta1 resulted in a significant decrease in the expression of MMP-1, while increasing the expression of TIMP-1 mRNA (p = 0.05). In contrast, MMP-3 and TIMP-2 expression was unaffected in mesothelial cells and in macrophages, compared to untreated controls. There was a significant increase in secreted MMP-1 and TIMP-2 by mesothelial cells following transforming growth factor-beta1 treatments in a time-dependent manner (p = 0.05 and p = 0.01), without affecting the secretion of these proteins by macrophages. A major portion of MMP-1 in the culture conditioned media of both cell types was found in complex with TIMP-1. The ratios of MMP-1/TIMPs production were significantly higher than MMP-3/TIMPs in mesothelial cells and macrophages, and progressively decreased following transforming growth factor-beta1 treatments (p < 0.05). In conclusion, these results indicate that mesothelial cells express MMP and TIMP mRNA and protein, and their expression is differentially regulated by transforming growth factor-beta1, a mechanism that in part may influence the outcome of peritoneal tissue repair and adhesion formation.

Analysis of Variance↗

Expression of the extracellular matrix metalloproteinase inducer (EMMPRIN) and the matrix metalloproteinase-2 in bronchopulmonary and breast lesions.

Tumor cells interact with stromal cells via soluble or cell-bound factors stimulating the production of matrix metalloproteinases (MMPs), a group of enzymes largely involved in the extracellular matrix (ECM) remodeling in tumor invasion. Among these factors, extracellular matrix metalloproteinase inducer (EMMPRIN) has been shown to stimulate in vitro the fibroblast production of various MMPs such as interstitial collagenase (MMP-1), stromelysin-1 (MMP-3), and gelatinase A (MMP-2). In this study, the EMMPRIN protein was detected by immunohistochemistry prominently in malignant proliferations of the breast and the lung. It was present at the surface of both tumor epithelial and peritumor stromal cells. Because previous studies have reported that stromal cells do not express EMMPRIN mRNAs, it is very likely that EMMPRIN is bound to stromal cells via a specific receptor. Moreover, our observations also demonstrated that the same peritumor stromal cells strongly express MMP-2. Our results show that EMMPRIN is an important factor in tumor progression by causing tumor-associated stromal cells to increase their MMP-2 production, thus facilitating tumor invasion and neoangiogenesis. (J Histochem Cytochem 47: 1575-1580, 1999)

Adenocarcinoma↗

Expression of matrix metalloproteinases and tissue inhibitor of matrix metalloproteinases in non-small-cell lung cancer.

Expression of matrix metalloproteinase (MMP)-2, MMP-9, tissue inhibitor of metalloproteinases (TIMP)-1, and TIMP-2 was studied in non-small-cell lung cancer (NSCLC). Activity of MMP-2 and MMP-9 by gelatin zymography and expression of MMP-2, MMP-9, TIMP-1, and TIMP-2 mRNAs were examined in 11 lung cancer cell lines which included six small-cell lung cancer (SCLC) cell lines. Localization of MMP-2, MMP-9, TIMP-1, and TIMP-2 was examined by immunohistochemistry in 43 resected NSCLC (22 adenocarcinomas, 17 squamous cell carcinomas, 4 large cell carcinomas) using specific anti-human monoclonal antibodies. Expression of MMP-2 mRNA was detected in 5 (100%), MMP-9 in 1 (20%), TIMP-1 in 4 (80%), and TIMP-2 in 5 (100%) of 5 NSCLC cell lines examined. MMP-2 gelatinolytic activity also was detected in all five NSCLC cell lines, whereas MMP-9 activity was detected in only one cell line. In 43 patients, MMP-2, MMP-9, TIMP-1, and TIMP-2 immunoreactivity was demonstrated in 19 (44%), 9 (21%), 15 (35%), and 29 (67%) excised tumors, respectively. All stromal fibroblasts in tumor samples stained positive for MMP-2. There was a correlation between TIMP-2 immunoreactivity and disease stage (42% stage I versus 88% stages II, III, and IV) (p = 0.0024). Both cancer cell lines and NSCLC tumor samples frequently expressed MMP-2, MMP-9, TIMP-1, and TIMP-2; MMP-2 in particular was highly expressed in malignant cells and surrounding fibroblasts. These findings suggest that MMP-2 plays a more important role in invasion of NSCLC than MMP-9 and that TIMP-2 may have clinical relevance in NSCLC.

Adenocarcinoma↗

Matrix metalloproteinase 3 (stromelysin) activates the precursor for the human matrix metalloproteinase 9.

Matrix metalloproteinase 9 (MMP-9), also known as 92-kDa gelatinase/type IV collagenase, is secreted from neutrophils, macrophages, and a number of transformed cells in zymogen form. Here we report that matrix metalloproteinase 3 (MMP-3/stromelysin) is an activator of the precursor of matrix metalloproteinase 9 (proMMP-9). MMP-3 initially cleaves proMMP-9 at the Glu40-Met41 bond located in the middle of the propeptide to generate an 86-kDa intermediate. Cleavage of this bond triggers a change in proMMP-9 that renders the Arg87-Phe88 bond susceptible to the second cleavage by MMP-3, resulting in conversion to an 82-kDa form. alpha 2-Macroglobulin binding studies of partially activated MMP-9 demonstrate that the 82-kDa species is proteolytically active, but not the initial intermediate of 86 kDa. This stepwise activation mechanism of proMMP-9 is analogous to those of other members of the MMP family, but the action of MMP-3 on proMMP-9 is the first example of zymogen activation that can be triggered by another member of the MMP family. The results imply that MMP-3 may be an effective activator of proMMP-9 in vivo.

Amino Acid Sequence↗

Regulation of matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases by Porphyromonas gingivalis in an engineered human oral mucosa model.

Under physiological conditions, matrix metalloproteinases (MMPs) are involved in the remodeling and turnover of periodontal tissue and their activity is tightly regulated by tissue inhibitors of metalloproteinases (TIMPs). Disturbances in the balance between MMPs and TIMPs may result in excessive tissue destruction. We previously used an engineered human oral mucosa (EHOM) model to demonstrate that Porphyromonas gingivalis, a major etiological agent of periodontitis, infiltrates connective tissue and induces significant loss of attachment of the stratified epithelium from the basement membrane. The aim of the present study was to investigate the effect of P. gingivalis on the expression and production of MMP-2, MMP-9, TIMP-1, and TIMP-2 by oral fibroblasts and epithelial cells. The EHOM model was infected with P. gingivalis ATCC 33277 or its derivative gingipain-null mutant (KDP128) for different periods of time. MMP and TIMP mRNA expression was evaluated by reverse transcription-polymerase chain reaction (RT-PCR) analysis, while protein secretion into the culture medium was assessed by enzyme-linked immunosorbent assays. P. gingivalis significantly up-regulated MMP-2 and MMP-9 mRNA expression by oral epithelial cells. This MMP gene activation was paralleled by TIMP-2 gene activation. However, only MMP-9 mRNA expression was significantly enhanced by the gingipain-null mutant. At 8 and 24 h post-infection, P. gingivalis increased significantly the MMP-9 protein level compared to the uninfected EHOM model. The present study reports the ability of P. gingivalis to regulate MMP and TIMP production by oral cells, a phenomenon that may contribute to tissue destruction.

Gene Expression Regulation, Enzymologic↗

Differential transcriptional activation of matrix metalloproteinase-2 and membrane type-1 matrix metalloproteinase by experimental deep venous thrombosis and thrombin.

OBJECTIVE: Resolution of deep venous thrombosis (DVT) is involved in the pathogenesis of postthrombotic syndrome. Matrix metalloproteinases (MMPs) are a family of proteolytic enzymes that are critical in angiogenesis and tissue remodeling. We hypothesized that MMP-2 and its membrane-bound activator membrane type-1 matrix metalloproteinase (MT1-MMP) expression would be expressed and activated during the resolution of DVT. METHODS: DVT was generated by caval ligation in wild-type and MMP-2 transgenic reporter mice. Ligated and sham-operated (control) cavae were analyzed for MMP-2 transcription (beta-galactosidase activity in MMP-2 reporter mice) and MT1-MMP mRNA by real-time polymerase chain reaction. MMP-2 activity was determined by zymography, and immunohistochemical staining for beta-galactosidase and MT1-MMP protein was used to localize expression. Human umbilical vascular endothelial cells (HUVEC) were treated with 10 U/mL thrombin and MMP-2 and MT1-MMP mRNA levels and MMP-2 activity was determined. RESULTS: MMP-2 activity increased 71% (n = 5, P < .05) at day 8 in ligated vs control cavae by zymography. beta-galactosidase activity showed a 1.2-fold (n = 8, P < .05) and 1.7-fold (n = 8, P < .05) induction in MMP-2 transcription at day 3 and day 8, respectively. No significant MT1-MMP gene induction was seen at day 3 in ligated vs control cavae, but MT1-MMP mRNA was upregulated 2.5-fold (n = 8, P < .05) in ligated cavae at day 8. Immunohistochemical staining localized MMP-2 and MT1-MMP expression to the vein wall and cellular infiltrates of the thrombus. Thrombin-treated HUVEC showed differential responses of MMP-2 and MT1-MMP. Zymography of conditioned media and cell lysates illustrated a 220% (152.6 +/- 8.6 vs 69.445 +/- 5.46 pixels/unit area, n = 5, P < .05) and 150% (74.1 +/- 7.3 vs 49.2 +/- 5.7 pixels/unit area, n = 5, P < .05) increases in MMP-2 activity respectively. MMP-2 mRNA levels were downregulated 30% (0.48 +/- 0.023 vs 0.63 +/- 0.035 copies of MMP-2 mRNA/copy GAPDH, n = 5, P < .05), whereas MT1-MMP message was upregulated 250% (0.147 +/- 0.009 vs 0.059 +/- 0.005 copies of MT1-MMP mRNA/copy GAPDH, n = 5, P < .05). CONCLUSIONS: Resolution of DVT is associated with increased MMP-2 transcription and activity as well as MT1-MMP expression. Thrombin may mediate the increase in MT1-MMP noted in DVT. This is the first article studying MMP-2 and MT1-MMP transcription in DVT. These findings add DVT resolution to the class of inflammatory and fibrotic disorders in which transcriptional activation of the MT1-MMP/MMP-2 genes occurs and identify a potential therapeutic target to modulate this clinically relevant process. CLINICAL RELEVANCE: Postthrombotic syndrome remains a significant clinical problem after deep venous thrombosis (DVT), but the cellular and molecular mechanisms involved in thrombus resolution and vein wall fibrosis remain undefined. Matrix metalloproteinase (MMP) enzymes are critical to cell migration and matrix breakdown. We identify gene transcription and activity of two MMP isoforms, MMP-2 and MMP-14 (membrane type MMP 1, MT1-MMP) in the resolution phase of experimental DVT and in thrombin-treated endothelial cells. These studies define new proteases potentially important to resolution of DVT and development of postthrombotic syndrome.

Animals↗