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MMP-9 Activity (mmp-9 + activity)
Selected AbstractsMercury Exposure Increases Circulating Net Matrix Metalloproteinase (MMP)-2 and MMP-9 ActivitiesBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 4 2009Anna L. B. Jacob-Ferreira We investigated whether there is an association between the circulating levels of MMP-2, MMP-9, their endogenous inhibitors (the tissue inhibitors of metalloproteinases; TIMPs) and the circulating Hg levels in 159 subjects environmentally exposed to Hg. Blood and plasma Hg were determined by inductively coupled plasma-mass spectrometry (ICP-MS). MMP and TIMP concentrations were measured in plasma samples by gelatin zymography and ELISA respectively. Thiobarbituric acid-reactive species (TBARS) were measured in plasma to assess oxidative stress. Selenium (Se) levels were determined by ICP-MS because it is an antioxidant. The relations between bioindicators of Hg and the metalloproteinases levels were examined using multivariate regression models. While we found no relation between blood or plasma Hg and MMP-9, plasma Hg levels were negatively associated with TIMP-1 and TIMP-2 levels, and thereby with increasing MMP-9/TIMP-1 and MMP-2/TIMP-2 ratios, thus indicating a positive association between plasma Hg and circulating net MMP-9 and MMP-2 activities. These findings provide a new insight into the possible biological mechanisms of Hg toxicity, particularly in cardiovascular diseases. [source] Combined effect of the finasteride and doxazosin on rat ventral prostate morphology and physiologyINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 3 2010Luis A. Justulin Jr Summary Finasteride (Fin) and Doxazosin (Dox), alone or in combination, have been widely used in treatment of benign prostatic hyperplasia (BPH) symptoms and recently have been suggested as potential drugs for prostate cancer (PCa)prevention and treatment. However, little is known about the effects of the combination therapy on prostate tissue morphology, physiology and matrix metalloproteinases (MMPs) activity, a special set of enzymes closely related to PCa progression and metastasis. In this study, adult Wistar rats were treated with Fin + Dox (25 mg/kg per day) and the ventral prostate (VP) was excised at days 3 and 30 of treatment to evaluate morphology, cell proliferation, death, transforming growth factor-beta1 (TGF-,1) protein expression, MMP-2, MMP-9 activities and MMP-2, MMP-9, TIMP-1 and TIMP-2 mRNA expression. Fin + Dox treatment induced a transient increase in testosterone (T) plasma concentration and a permanent reduction in dihydrotestosterone (DHT). The VP and epithelial cell proliferation were reduced and the stromal collagen fibre volume fraction and apoptosis of the epithelial cell were increased. Fin + Dox treatment also increased the TGF-,1 immunoreaction in the epithelium and in the stroma. The mRNAs for MMP-2, TIMPs-1 and -2 expressions after 30 days of treatment were decreased. The mRNA for MMP-9 was not detected in any of the groups analysed. Fin + Dox treatment for 30 days promoted a decrease in gelatinolytic activity of MMP-2 and an increase in MMP-9. In conclusion, combined treatment with Fin and Dox interferes in the epithelial cell behaviour and in the MMPs activity, potentially via TGF-,1-mediated and androgen pathways. Our results contribute to a better understanding of the clinical data and also of the molecular mechanisms behind isolated or combined Fin and Dox long-term treatment. [source] Active MMP-2 effectively identifies the presence of colorectal cancerINTERNATIONAL JOURNAL OF CANCER, Issue 12 2009Mary Jo Murnane Abstract Fully active MMP-2 is expressed at such low levels in human tissues that studies often fail to confirm its value as a cancer marker despite strong associations with malignancy. Our study utilized careful extraction, accurate activity measurements, standardization to purified controls and a new statistical metric to determine whether active MMP-2 is an effective indicator of colorectal cancer compared to pro-MMP-2 or pro-MMP-9. MMP-2 and MMP-9 activities were analyzed in matched normal and cancer samples from 269 patients by gelatin zymography, computer-assisted image analysis, serial dilutions of strong samples and standardization to controls. An index of effect size was designed for comparative evaluation of active MMP-2, pro-MMP-2 and pro-MMP-9 activities. For each gelatinase, mean activity and protein levels/mg soluble protein in normal mucosa and colorectal cancer were calculated for the first time with respect to commercial standards. Active MMP-2 activity, detected in 99% of colorectal cancers, was higher in 95% of cancers (on average 10-fold) than in normal mucosa. Levels of pro-MMP-2 and pro-MMP-9, but not active MMP-9, activities were also significantly higher in cancers versus normal. However, active MMP-2 activity provided the most effective test for the presence of cancer (p < 0.0.0001) with an effect size statistically significantly larger than for either pro-MMP-2 or pro-MMP-9. Receiver operating characteristic (ROC) curves demonstrated that a cut-off for active MMP-2 of >44 SDU activity/mg soluble protein (>180 pg/mg), which is three times mean normal levels, would permit detection of colorectal cancer with an estimated sensitivity of 84% and estimated specificity of 93%. © 2009 UICC [source] Metalloproteinase expression in normal and malignant oral keratinocytes: stimulation of MMP-2 and -9 by scatter factorEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 4 2000J. H. Bennett Matrix metalloproteinases (MMPs) are Zn2+ dependent proteases produced by a variety of cell types. They have a fundamental role in tissue remodelling, tumour invasion and metastasis. Scatter factor (SF), secreted by fibroblasts, has a paracrine action on epithelial cells and binds the trans-membrane c-met receptor inducing loss of adhesion, cell motility and invasiveness in vitro. The purpose of this study was to test if SF can regulate the production of MMPs by epithelial cells. Supernatants from oral squamous cell carcinoma-derived cells (H375 and H376), a human keratinocyte line (UP), and primary cultures of oral mucosal keratinocytes, grown in the presence or absence of SF, were analysed using 0.1% gelatin zymography. MMPs were characterised by comparison with human recombinant enzymes and by the use of specific inhibitors. Oral mucosal keratinocytes, UP, and H357 cells expressed MMP-2 and MMP-9, whilst H376 cells only expressed MMP-2. SF increased the expression of MMP-9 in UP and MMP-2 in H376 supernatants. Both MMP-2 and MMP-9 activity were increased in H357 and normal keratinocyte supernatants. This could be blocked using a human recombinant anti-SF antibody. In all epithelial lines tested, c-Met, the cell surface receptor for SF, could be detected. The results indicate that SF stimulates MMP expression in UP, H376, H357, and normal oral mucosal cells and points to a role for SF in the regulation of oral keratinocyte behaviour in wound healing and neoplasia. [source] Thioredoxin alters the matrix metalloproteinase/tissue inhibitors of metalloproteinase balance and stimulates human SK-N-SH neuroblastoma cell invasionFEBS JOURNAL, Issue 2 2001Antonietta R. Farina Thioredoxin (Trx) inhibited tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 activity with an approximate IC50 of 0.3 µm, matrix metalloproteinase (MMP)-2 activity with an approximate IC50 of 2 µm but did not inhibit MMP-9 activity. This differential capacity of Trx to inhibit TIMP and MMP activity resulted in the promotion of MMP-2 and MMP-9 activity in the presence of molar TIMP excess. Inhibition of TIMP and MMP-2 activity by Trx was dependent upon thioredoxin reductase (TrxR), was abolished by Trx catalytic site mutation and did not result from TIMP or MMP-2 degradation. HepG2 hepatocellular carcinoma cells induced to secrete Trx inhibited TIMP activity in the presence of TrxR. SK-N-SH neuroblastoma cells secreted TrxR, which inhibited TIMP and MMP-2 activity in the presence of Trx. Trx stimulated SK-N-SH invasive capacity in vitro in the absence of exogenous TrxR. This study therefore identifies a novel extracellular role for the thioredoxin/thioredoxin reductase redox system in the differential inhibition of TIMP and MMP activity and provides a novel mechanism for altering the TIMP/MMP balance that is of potential relevance to tumor invasion. [source] Finasteride treatment alters MMP-2 and -9 gene expression and activity in the rat ventral prostateINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 1 2010Flávia K. Delella Summary The safety of using finasteride as a prevention of prostate cancer is still under debate. In this study, we investigated the effects of finasteride on the location, gene expression and activities of matrix metalloproteinases -2 and -9, which are involved in the degradation of extracellular matrix components during tissue remodelling and prostate cancer progression, invasion and metastasis. Ventral prostates (VP) from Wistar rats treated with finasteride (25 mg/kg/day) for 7 and 30 days and age-matched controls were evaluated using histology, immunohistochemistry, semi-quantitative RT-PCR and gelatin zymography. Finasteride treatment reduced the epithelial immunostaining of MMP-2 but increased MMP-9 immunostaining in the epithelial cells and in the stroma. The mRNA expression of both MMP-2 and MMP-9 were significantly increased on day 7 of finasteride treatment, mainly for MMP-9 and returned to the control levels by day 30. However, gelatin zymography showed that MMP-9 activity was significantly increased on day 7 of finasteride treatment and remained elevated on day 30 (p < 0.05), while MMP-2 activity was reduced after 30 days of treatment. Finasteride increases MMP-9 and reduces MMP-2 activities in the prostate, which may affect negatively and positively both normal and tumoural prostatic cell behaviour during the treatment. Studies on expression of MMPs in the prostate during different androgen manipulation or cancer chemoprevention strategies can contribute to understand the tissue's overall response and clinical data. [source] The hemopexin domain of MMP-9 inhibits angiogenesis and retards the growth of intracranial glioblastoma xenograft in nude miceINTERNATIONAL JOURNAL OF CANCER, Issue 2 2009Ravesanker Ezhilarasan Abstract Matrix Metalloproteinase-9 (MMP-9) consists of a prodomain, catalytic domain with 3 fibronectin-like type II modules and C-terminal hemopexin-like (PEX) domain. These domains play distinct roles in terms of proteolytic activity, substrate binding and interaction with inhibitors and receptors. To assess the potential of the MMP-9-PEX domain to interfere with tumor progression, we stably transfected human glioblastoma cells with an expression vector containing a cDNA sequence of the MMP-9-PEX. The selected clones exhibited decreased MMP-9 activity and reduced invasive capacity. We assessed how secretion of MMP-9-PEX by glioblastoma cells affects angiogenic capabilities of human microvascular endothelial cells (HMECs) in vitro. MMP-9-PEX conditioned medium treatment caused a reduction in migration of HMECs and inhibited capillary-like structure formation in association with suppression of vascular endothelial growth factor (VEGF) secretion and VEGF receptor-2 protein level. The suppression of HMECs survival by conditioned medium from MMP-9-PEX stable transfectants was associated with apoptosis induction characterized by an increase in cells with a sub-G0/G1 content, fragmentation of DNA, caspase-3, -8 and -9 activation and poly (ADP-ribose) polymerase (PARP) cleavage. A significant tumor growth inhibition was observed in intracranial implants of MMP-9-PEX stable transfectants in nude mice with attenuation of CD31 and MMP-9 protein expression. These results demonstrate that MMP-9-PEX inhibits angiogenic features of endothelial cells and retards intracranial glioblastoma growth. © 2008 Wiley-Liss, Inc. [source] Evaluation of a magnetic resonance biomarker of osteoarthritis disease progression: doxycycline slows tibial cartilage loss in the Dunkin Hartley guinea pigINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 2 2009Jonathan Bowyer Summary The objective was to assess the effect of doxycycline treatment on a magnetic resonance imaging (MRI) biomarker of cartilage volume loss, and on matrix metalloproteinase (MMP) activity in a guinea pig osteoarthritis model. Guinea pigs (9 months old) were dosed with vehicle or doxycycline, 0.6, 3.0 mg/kg/day for 66 days. Fat-suppressed 3D gradient-echo MRI of the left knee was acquired pre- and post dosing. Change in medial tibial plateau (MTP) cartilage volume (MT.VC) was determined using image analysis. At termination, MTP cartilage was removed from knees and proteolytic MMP activity determined using a fluorescent peptide substrate assay. Vehicle-treated animals lost 20.5% (95% CI mean 25.6,15.1) MT.VC. The doxycycline (0.6 mg/kg/day) group lost 8.6% (P < 0.05, 95% CI 20.6 to ,5.3) whilst the 3.0 mg/kg/day group lost 10.0% (P < 0.05, 95% CI 13.9,6.0%). Endogenous levels of active MMPs were below limits of detection in all samples. However, doxycycline treatment ablated amino phenyl mercuric acid activated MMP-13 and MMP-8 levels, reduced MMP-9 levels by 65% and MMP-1 levels by 24%. Doxycycline treatment resulted in partial protection from MT.VC loss and was associated with complete reduction in MMP-13 and MMP-8, and partial reduction in MMP-9 activity. These data imply a role of MMPs in cartilage degeneration but incomplete protection suggests that additional doxycycline insensitive mechanisms are important in this model. The protective effect of doxycycline correlates with the clinical finding of lessened joint space narrowing, strengthens the utility of this animal model in identifying disease-modifying osteoarthritic drugs and supports the use of MRI biomarkers of cartilage loss. [source] Ascochlorin suppresses oxLDL-induced MMP-9 expression by inhibiting the MEK/ERK signaling pathway in human THP-1 macrophagesJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2007Jeong Han Kang Abstract The critical initiating event in atherogenesis involves the invasion of monocytes through the endothelial walls of arteries and the transformation of monocytes from macrophages into foam cells. Human THP-1 monocytic cells can be induced to differentiate into macrophages by phorbol myristate acetate (PMA) and can then be converted into foam cells by exposure to oxidized low-density lipoprotein (oxLDL). Also, during a chronic inflammatory response, monocytes/macrophages produce the 92-kDa matrix metalloproteinase-9 (MMP-9) that may contribute to the extravasation, migration, and tissue remolding capacities of the phagocytic cells. Here, we investigate the effect of ascochlorin (ASC), a prenylphenol antiviral compound from the fungus Ascochyta viciae, on oxLDL-induced MMP-9 expression and activity in human THP-1 macrophages. ASC reduced oxLDL-induced MMP-9 expression and activity in a time-dependent and dose-dependent manner. Also, an analysis of MMP-9 activity using pharmacologic inhibitors showed that ASC inhibits MMP-9 activity via the extracellular signal-regulated kinase 1 and kinase 2 pathways. Our results suggest that ASC may be useful as a potent clinical antiatherogenic agent, a topic of considerable interest in the biological chemistry of chemotherapeutic agents. J. Cell. Biochem. 102: 506,514, 2007. © 2007 Wiley-Liss, Inc. [source] Role of melatonin in regulating matrix metalloproteinase-9 via tissue inhibitors of metalloproteinase-1 during protection against endometriosisJOURNAL OF PINEAL RESEARCH, Issue 4 2008Sumit Paul Abstract:, Endometriosis is a gynecological disease of women and plausibly regulated by matrix metalloproteinases (MMPs). However, mechanisms of alterations in MMPs during endometriosis remain unclear. Human endometriotic tissues possessing varying degrees of severity were examined for expression of MMPs and tissue inhibitors of metalloproteinase (TIMP)-1. In addition, endometriosis was generated in mice and endometriotic tissues were tested for MMP-9 activity. Results show significant upregulation of secreted and synthesized proMMP-9 activity with duration and severity of endometriosis. Along with upregulation of activity, the expression of proMMP-9 was found increased while TIMP-1 expression followed an inverse trend. The effect of melatonin, a major secretory product of the pineal gland, on endometriosis was examined in preventive and therapeutic models in mice. The results show that melatonin arrested lipid peroxidation and protein oxidation and downregulated proMMP-9 activity and expression in a time and dose-dependent manner while protecting and regressing peritoneal endometriosis. Moreover, the attenuated activity and expression of proMMP-9 were associated with subsequent elevation in the expression of TIMP-1. Our study reveals for the first time the role of melatonin in arresting peritoneal endometriosis in mice and a novel marker, expression ratio of proMMP-9 versus TIMP-1, was identified for assessing severity and progression of endometriosis. [source] Activation of cartilage matrix metalloproteinases by activated protein CARTHRITIS & RHEUMATISM, Issue 3 2009Miriam T. Jackson Objective To investigate the role of activated protein C (APC) in cartilage degradation. Methods Chondrocyte expression of protein C, endothelial protein C receptor (EPCR), and thrombomodulin (TM) were evaluated by reverse transcription,polymerase chain reaction (RT-PCR). APC was immunolocalized in developing joints and in osteoarthritic (OA) cartilage from humans. The effect of APC on aggrecan and collagen degradation was examined in explant cultures of ovine cartilage in control cultures and in cultures stimulated with interleukin-1, (IL-1,), tumor necrosis factor , (TNF,), or retinoic acid (RetA), using colorimetric assays and Western blotting. Chondrocyte expression of matrix metalloproteinases (MMPs), ADAMTS, and tissue inhibitor of metalloproteinases (TIMPs) was measured by RT-PCR. MMP-2 and MMP-9 activity was evaluated by gelatin zymography and MMP-13 by fluorogenic assay. Results Positive cellular immunostaining for APC was found at sites of MMP activity in developing joints and in OA, but not normal, cartilage. Chondrocytes expressed messenger RNA for protein C, EPCR, and TM, with the latter 2 levels increased by IL-1, and TNF, stimulation. APC augmented aggrecan release and initiated collagen breakdown in IL-1,,treated and TNF,-treated cartilage, but not in normal or in RetA-treated cartilage. APC-stimulated aggrecan and collagen breakdown were due to MMP activity but were not associated with modulation of MMP, ADAMTS, or TIMP expression. APC resulted in MMP-13 activation in cartilage cultures. APC could not directly activate proMMP-13, but it was associated with increased MMP-2 and MMP-9 activity. Conclusion APC may be a relevant activator of MMPs in cartilage and may play a role in progressive cartilage degradation in arthritis. [source] Neutrophil gelatinase,associated lipocalin is expressed in osteoarthritis and forms a complex with matrix metalloproteinase 9ARTHRITIS & RHEUMATISM, Issue 10 2007Kalpana Gupta Objective Expression of matrix metalloproteinase 9 (MMP-9) is up-regulated in osteoarthritis (OA) and usually presents as multiple bands when synovial fluid (SF) from OA patients is analyzed by zymography. Among these bands is an ,125,130,kd band for high molecular weight (HMW) gelatinase, which has not been characterized. This study was undertaken to characterize the HMW MMP activity in OA SF. Methods MMP activity in OA SF was determined by gelatin zymography. Recombinant MMPs were used to identify MMP activity on the zymogram. Western immunoblotting, immunoprecipitation, and immunodepletion analyses were performed using antibodies specific for human MMP-9 and human neutrophil gelatinase,associated lipocalin (NGAL). Human cartilage matrix degradation was determined by dimethylmethylene blue assay. Results Zymographic analysis showed that the HMW gelatinase in OA SF comigrated with a purified NGAL,MMP-9 complex. Results of Western immunoblotting showed that the HMW gelatinase was also recognized by antibodies specific for human NGAL or human MMP-9. These same antibodies also immunoprecipitated the HMW gelatinase activity from OA SF. The NGAL,MMP-9 complex was reconstituted in vitro in gelatinase buffer. In the presence of NGAL, MMP-9 activity was stabilized; in the absence of NGAL, rapid loss of MMP-9 activity occurred. MMP-9,mediated release of cartilage matrix proteoglycans was significantly higher in the presence of NGAL (P < 0.05). Conclusion Our findings demonstrate that the HMW gelatinase activity in OA SF represents a complex of NGAL and MMP-9. The ability of NGAL to protect MMP-9 activity is relevant to cartilage matrix degradation in OA and may represent an important mechanism by which NGAL may contribute to the loss of cartilage matrix proteins in OA. [source] FK506 promotes melanocyte and melanoblast growth and creates a favourable milieu for cell migration via keratinocytes: possible mechanisms of how tacrolimus ointment induces repigmentation in patients with vitiligoBRITISH JOURNAL OF DERMATOLOGY, Issue 3 2005C-C.E. Lan Summary Background, Vitiligo is an acquired pigmentary disorder characterized by depigmentation of skin and hair. As the pathogenesis of this disease is still obscure, the treatment of vitiligo has generally been unsatisfactory and often disappointing. Topical tacrolimus (FK506) ointment has recently been added to the armamentarium against this pigmentary disorder. Despite its clinical efficacy, the underlying mechanisms of how topical tacrolimus induces repigmentation in vitiligo have rarely been investigated. As tacrolimus ointment is applied directly to the skin, its impact on keratinocytes (KCs) requires thorough investigation. Objectives, To investigate the effects of FK506 on melanocyte (MC) and melanoblast (MB) growth via KCs. Methods, Cultured MCs and MBs were treated with supernatant of KC cultures conditioned with various concentrations of FK506. The impact of supernatant on MCs and MBs was assessed in terms of its effect on MC/MB proliferation, melanin formation and cell migration. The activities of matrix metalloproteinase (MMP)-2 and MMP-9, known for their influence on cell migration, were evaluated. The concentrations of MC/MB growth factors in the KC supernatant were also determined. Results, Results demonstrated that proliferation of both MCs and MBs was significantly enhanced by FK506-treated KC supernatant. In addition, the concentration of stem cell factor in KC supernatant increased dose-dependently with FK506 treatment. The supernatant from FK506-treated KC culture showed a significant increase in MMP-9 activity. Conclusions, Our study provides in vitro evidence demonstrating that direct interaction between FK506 and KCs creates a favourable milieu for MC growth and migration. Furthermore, our findings provide a possible mechanism explaining how tacrolimus ointment induces repigmentation in patients with vitiligo. [source] Interactions of tachykinin receptor antagonists with lipopolysaccharide-induced airway inflammation in miceCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 9 2004M Veron Summary 1.,Several observations suggest that tachykinins are involved in the pathogenesis of bronchopulmonary alterations. We have investigated the effect of antagonists for tachykinin NK1 (SR 140333), NK2 (SR 48968) or NK3 (SR 142801) receptors on inflammatory cell recruitment, tumour necrosis factor (TNF)-, and interleukin (IL)-6 release and matrix metalloproteinase (MMP)-9 activity in the bronchoalveolar lavage fluid (BALF) of mice exposed to lipopolysaccharide (LPS; 100 µg/mL aerosol for 30 min). 2.,Treatment of mice with a combination of SR 140333 and SR 48968 (10,6 mol/L, aerosol) significantly reduced the increase in the number of total cells and neutrophils and MMP-9 activity in the BALF of mice 2.5 h after LPS exposure. Treatment with the NK3 antagonist SR 142801 (10,6 mol/L, aerosol) did not inhibit the influx of neutrophils, but markedly reduced the increase in TNF-, and IL-6 levels at 2.5 h and MMP-9 activity at 20 h. 3.,These results show that the three tachykinin receptor antagonists may interfere with the development of airway inflammation, namely neutrophilia, TNF-, release or MMP-9 activity in the BALF of mice exposed to LPS and suggest that not only NK1 and NK2 receptors, but also NK3 receptors are involved in the modulation of the inflammatory response and airway remodelling. [source] | |||||||||||||