Zymography

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Zymography

  • casein zymography
  • gelatin zymography


  • Selected Abstracts


    Matrix metalloproteinases 2 and 9 in human atherosclerotic and non-atherosclerotic cerebral aneurysms

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 10 2006
    J. Caird
    Matrix metalloproteinases 2 and 9 (MMP 2 and -9) have been implicated in the pathogenesis of atherosclerosis and aneurysm formation. The goal of the study was to establish the role of these metalloproteinases in both human atherosclerotic and non-atherosclerotic cerebral aneurysms. Eleven cerebral aneurysms (four atherosclerotic, seven non-atherosclerotic) were immunohistochemically stained for MMP 2 and -9. As controls, atherosclerotic and normal Circle of Willis arteries were similarly immunostained. All specimens were retrieved at autopsy and were paraffin-embedded. In order to evaluate the real MMP 2 and -9 activities, gelatin zymography was also performed in only two available specimens of non-atherosclerotic intracranial aneurysms, because of the relative unavailability of fresh intracranial aneurysm tissue (i.e. reluctance to excise the aneurysm fundus at surgery). Our data establish that MMP 2 and -9 were expressed minimally or not at all in normal Circle of Willis arteries but were strongly expressed in medial smooth muscle cells of atherosclerotic Circle of Willis arteries. In the aneurysm group, both MMP 2 and -9 were strongly expressed in the atherosclerotic aneurysms, but MMP 2 alone was detected in the non-atherosclerotic aneurysms. Zymography revealed a weak enzyme activity correlating to MMP 9 standard recombinant protein. MMP 2 activity was not demonstrated in either specimen. This study shows that the expression of MMP 2 and -9 is associated with atherosclerosis, be it in aneurysmal or non-aneurysmal cerebral vessels but MMP 2 appears to be specifically expressed in aneurysms devoid of atherosclerosis perhaps suggesting a pathogenic role for MMP 2 in the alteration of the extracellular matrix of cerebral arteries during aneurysm formation. [source]


    AUF-1 mediates inhibition by nitric oxide of lipopolysaccharide-induced matrix metalloproteinase-9 expression in cultured astrocytes

    JOURNAL OF NEUROSCIENCE RESEARCH, Issue 2 2006
    Wenlan Liu
    Abstract Neuroinflammatory diseases are associated with increased production of matrix metalloproteinase-9 (MMP-9) and excessive generation of nitric oxide (NO). NO hasbeen reported to have variable effects on MMP-9 gene expression and activation in various cell types. Inthe present study, we investigated the effect of NOon MMP-9 expression in primary cortical astrocytes. Zymography and real-time PCR showed that lipopolysaccharide (LPS) dramatically increased latent MMP-9 gelatinolytic activity and MMP-9 mRNA expression. By using the NO donor DETA NONOate, we observed a dose-dependent inhibition of MMP-9 induction by LPS. Active forms of MMP-9 were not found by zymography after NO treatment. The MEK1/2 inhibitor U0126 completely inhibited LPS-induced MMP-9, which was partially inhibited by the p38 MAPK inhibitor SB203580. NO had no effect on LPS-stimulated ERK1/2 and p38 MAPK activation, suggesting that the inhibitory action of NO occurs downstream of MAPK cascades. Real-time PCR analysis showed that NO accelerated the degradation of MMP-9 mRNA after LPS induction. Western blotting and pull-down assay demonstrated that NO increased AUF-1 expression as well as its specific binding to the MMP-9 gene 3,-untranslated region. Knockdown of AUF-1 with siRNA partially reversed the inhibitory action of NO on LPS-stimulated MMP-9 induction. We conclude that NO does not activate MMP-9 in astrocyte cultures but reduces LPS-induced MMP-9 expression via accelerating MMP-9 mRNA degradation, which is partially mediated by AUF-1. Our results suggest that elevated NO concentrations may suppress MMP-9 and restrict the inflammatory response in neurodegenerative diseases. © 2006 Wiley-Liss, Inc. [source]


    Salivary matrix metalloproteinase (MMP-8) levels and gelatinase (MMP-9) activities in patients with type 2 diabetes mellitus

    JOURNAL OF PERIODONTAL RESEARCH, Issue 5 2000
    Hanna-Leena Collin
    We studied the salivary levels and activities of the matrix metalloproteinases (MMP)-8 and -9 in 45 type 2 diabetic patients and 77 control subjects. The patients' mean glycosylated haemoglobin (HbAlc) was 8.7%, indicating an unsatisfactory metabolic control of the disease. The MMP levels were further related to the clinical and microbiological periodontal findings as well as to salivary flow rate and other factors. The salivary flow rate, albumin and amylase concentrations were similar in type 2 diabetic patients to those in the control group. The mean gingival and periodontal pocket indexes were higher in the diabetes group. The number of potential periodontopathogenic bacteria was lower, however, in the diabetic than in the control group. Zymography and immunoblotting revealed that the major MMPs in the type 2 diabetic patients' saliva were MMP-8 and MMP-9. Salivary MMP levels and activities in type 2 diabetic patients were in general similar to those in the control group. However, the correlation coefficients using multiple regression analysis revealed that gingival bleeding, pocket depths and HbAlc were associated with increased MMP-8 levels which, in turn, were negatively predicted by elevated plasma lipid peroxide levels in the diabetic group. Our data on salivary MMP-8 and -9 do not support the concept of generalized neutrophil dysfunction in unbalanced diabetes. Moreover, plasma lipid peroxidation levels reflecting the increased oxidative burden, which is generated mainly by triggered neutrophils, do not indicate neutrophil dysfunction due to diabetes, but may rather be related to the increased tissue damage in an uncontrolled disease. However, advanced periodontitis in type 2 diabetes seems to be related to elevated salivary MMP-8 levels which might be useful in monitoring periodontal disease in diabetes. [source]


    Absence of tissue inhibitor of metalloproteinases 3 disrupts alveologenesis in the mouse

    DEVELOPMENT GROWTH & DIFFERENTIATION, Issue 1 2009
    Sean E. Gill
    Tissue inhibitors of metalloproteinases (TIMPs) regulate extracellular matrix (ECM) degradation by matrix metalloproteinases (MMPs) throughout lung development. We examined lungs from TIMP3 null mice and found significant air space enlargement compared with wild type (WT) animals during a time course spanning early alveologenesis (post-partum days 1, 5, 9 and 14). Trichrome staining revealed a similar pattern of collagen distribution in the walls of nascent alveoli; however, the alveolar walls of TIMP3 mutant mice appeared to be thinner than controls. Assessment of MMP2 and MMP9 activities by gelatin zymography demonstrated a significant elevation in the active form of MMP2 at post-partum days 1 and 5. Treatment of null pregnant dams with a broad spectrum synthetic metalloproteinase inhibitor, GM6001, on embryonic day 16.5 enhanced the formation of primitive alveoli during the saccular stage of lung development as evidenced by a partial, but significant, rescue of alveolar size in post-partum day 1 animals. We propose that increased MMP activity in the absence of TIMP3 enhances ECM proteolysis, upsetting proper formation of primitive alveolar septa during the saccular stage of alveologenesis. Therefore, TIMP3 indirectly regulates alveolar formation in the mouse. To our knowledge, ours is the first study to demonstrate that in utero manipulation of the TIMP/MMP proteolytic axis, to specifically inhibit proteolysis, significantly affects lung development. [source]


    Matrix metalloproteinases mediate the dismantling of mesenchymal structures in the tadpole tail during thyroid hormone-induced tail resorption

    DEVELOPMENTAL DYNAMICS, Issue 3 2002
    Jae-Chang Jung
    Abstract It has been suggested that a family of tissue remodelling enzymes called matrix metalloproteinases (MMPs) play a causal role in the process of tail resorption during thyroid hormone-induced metamorphosis of the anuran tadpole; however, this hypothesis has never been directly substantiated. We cloned two new Xenopus MMPs, gelatinase A (MMP-2) and MT3-MMP (MMP-16), and the MMP inhibitor TIMP-2. These clones were used along with several others to perform a comprehensive expression study. We show that all MMPs and TIMP-2 are dramatically induced in the resorbing tail during spontaneous metamorphosis and are spatially coexpressed, primarily in the remodelling mesenchymal tissues. By Northern blotting, we show that all the examined MMPs/TIMP-2 are also induced by treatment of organ-cultured tails with thyroid hormone (T3). Using the organ culture model, we provide the first direct evidence that MMPs are required for T3 -induced tail resorption by showing that a synthetic inhibitor of MMP activity/expression can specifically retard the resorption process. By gelatin zymography, we also show T3 induction of a fifth MMP, preliminarily identified as gelatinase B (GelB; MMP-9). Moreover, T3 not only induces MMP/TIMP expression but also MMP activation, and we provide evidence that TIMP-2 participates in the latter process. These findings suggest that MMPs and TIMPs act in concert to effect the dismantling of mesenchymal structures during T3 -induced metamorphic tadpole tail resorption. © 2002 Wiley-Liss, Inc. [source]


    Maternal hypoxia increases the activity of MMPs and decreases the expression of TIMPs in the brain of neonatal rats

    DEVELOPMENTAL NEUROBIOLOGY, Issue 3 2010
    Wenni Tong
    Abstract A recent study has shown that increased activity of matrix metalloproteinases-2 and metalloproteinases-9 (MMP-2 and MMP-9) has detrimental effect on the brain after neonatal hypoxia. The present study determined the effect of maternal hypoxia on neuronal survivability and the activity of MMP-2 and MMP-9, as well as the expression of tissue inhibitors of metalloproteinase 1 and 2 (TIMP-1 and TIMP-2) in the brain of neonatal rats. Pregnant rats were exposed to 10.5% oxygen for 6 days from the gestation day 15 to day 21. Pups were sacrificed at day 0, 4, 7, 14, and 21 after birth. Body weight and brain weight of the pups were measured at each time point. The activity of MMP-2 and MMP-9 and the protein abundance of TIMP-1 and TIMP-2 were determined by zymography and Western blotting, respectively. The tissue distribution of MMPs was examined by immunofluorescence staining. The neuronal death was detected by Nissl staining. Maternal hypoxia caused significant decreases in body and brain size, increased activity of MMP-2 at day 0, and increased MMP-9 at day 0 and 4. The increased activity of the MMPs was accompanied by an overall tendency towards a reduced expression of TIMPs at all ages with the significance observed for TIMPs at day 0, 4, and 7. Immunofluorescence analysis showed an increased expression of MMP-2, MMP-9 in the hippocampus at day 0 and 4. Nissl staining revealed significant cell death in the hippocampus at day 0, 4, and 7. Functional tests showed worse neurobehavioral outcomes in the hypoxic animals. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2010 [source]


    Increased myocardial matrix metalloproteinases in hypoxic newborn pigs during resuscitation: effects of oxygen and carbon dioxide

    EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 7 2004
    W. B. Borke
    Abstract Background, Perinatal asphyxia is associated with cardiac dysfunction, and it is important to prevent further tissue injury during resuscitation. There is increasing evidence that myocardial matrix metalloproteinases (MMPs) are involved in myocardial hypoxaemia,reoxygenation injury. Objective, To assess MMPs and antioxidant capacity in newborn pigs after global ischaemia and subsequent resuscitation with ambient air or 100% O2 at different PaCO2 -levels. Methods, Newborn pigs (12,36 h of age) were resuscitated for 30 min by ventilation with 21% or 100% O2 at different PaCO2 levels after a hypoxic insult, and thereafter observed for 150 min. In myocardial tissue extracts, MMPs were analyzed by gelatin zymography and broad matrix-degrading capacity (total MMP). Total endogenous antioxidant capacity in myocardial tissue extracts was measured by the oxygen radical absorbance capacity (ORAC) assay. Results, Matrix metalloproteinase-2 more than doubled from baseline values (P < 0·001), and was higher in piglets resuscitated with 100% O2 than with ambient air (P = 0·012). The ORAC value was considerably decreased (P < 0·001). In piglets with elevated PaCO2, total MMP-activity in the right ventricle was more increased than in the left ventricle (P = 0·008). In the left ventricle, total MMPactivity was higher in the piglets with low PaCO2 than in the piglets with elevated PaCO2 (P = 0·013). Conclusion, In hypoxaemia-reoxygenation injury the MMP-2 level was highly increased and was most elevated in the piglets resuscitated with 100% O2. Antioxidant capacity was considerably decreased. Assessed by total MMP-activity, elevated PaCO2 during resuscitation might protect the left ventricle, and probably increase right ventricle injury of the myocardium. [source]


    Matrix metalloproteinases 2 and 9 in human atherosclerotic and non-atherosclerotic cerebral aneurysms

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 10 2006
    J. Caird
    Matrix metalloproteinases 2 and 9 (MMP 2 and -9) have been implicated in the pathogenesis of atherosclerosis and aneurysm formation. The goal of the study was to establish the role of these metalloproteinases in both human atherosclerotic and non-atherosclerotic cerebral aneurysms. Eleven cerebral aneurysms (four atherosclerotic, seven non-atherosclerotic) were immunohistochemically stained for MMP 2 and -9. As controls, atherosclerotic and normal Circle of Willis arteries were similarly immunostained. All specimens were retrieved at autopsy and were paraffin-embedded. In order to evaluate the real MMP 2 and -9 activities, gelatin zymography was also performed in only two available specimens of non-atherosclerotic intracranial aneurysms, because of the relative unavailability of fresh intracranial aneurysm tissue (i.e. reluctance to excise the aneurysm fundus at surgery). Our data establish that MMP 2 and -9 were expressed minimally or not at all in normal Circle of Willis arteries but were strongly expressed in medial smooth muscle cells of atherosclerotic Circle of Willis arteries. In the aneurysm group, both MMP 2 and -9 were strongly expressed in the atherosclerotic aneurysms, but MMP 2 alone was detected in the non-atherosclerotic aneurysms. Zymography revealed a weak enzyme activity correlating to MMP 9 standard recombinant protein. MMP 2 activity was not demonstrated in either specimen. This study shows that the expression of MMP 2 and -9 is associated with atherosclerosis, be it in aneurysmal or non-aneurysmal cerebral vessels but MMP 2 appears to be specifically expressed in aneurysms devoid of atherosclerosis perhaps suggesting a pathogenic role for MMP 2 in the alteration of the extracellular matrix of cerebral arteries during aneurysm formation. [source]


    Metalloproteinase expression in normal and malignant oral keratinocytes: stimulation of MMP-2 and -9 by scatter factor

    EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 4 2000
    J. 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]


    In vitro induction of matrix metalloproteinase-2 and matrix metalloproteinase-9 expression in keratinocytes by boron and manganese

    EXPERIMENTAL DERMATOLOGY, Issue 8 2004
    Nathalie Chebassier
    Abstract:, Matrix metalloproteinase (MMP)-2 and MMP-9 are involved in keratinocyte migration and granulation tissue remodeling during wound healing. Thermal water cures are sometimes proposed as complementary treatment for accelerating healing of wounds resulting from burns and/or surgery, but their mechanisms of action remain unknown. Some thermal waters are rich in trace elements such as boron and manganese. Interestingly, clinical studies have shown the beneficial effects of trace elements such as boron and manganese for human wound healing. To try to specify the role of trace elements in cutaneous healing, the present study investigated the effects of these trace elements on the production of MMP-2 and MMP-9 by normal human keratinocytes cultured in vitro. Immunohistochemistry and Western blot showed that intracellular MMP-9 expression in keratinocytes was induced when incubated for 6 h with boron at 10 µg/ml or manganese at 0.2 µg/ml. Moreover, gelatin zymography on keratinocyte supernatants showed an increase of gelatinase secretion after 24 h of incubation of keratinocytes with boron or manganese, regardless of concentration. Gelatinase secretion was not associated with keratinocyte proliferation induced by trace elements. Thus, our results suggest that boron and manganese could play a role in the clinical efficiency of thermal water on wound healing. [source]


    Secretion of proteases in serglycin transfected Madin,Darby canine kidney cells

    FEBS JOURNAL, Issue 3 2006
    Lillian Zernichow
    Madin,Darby canine kidney (MDCK) cells, which do not normally express the proteoglycan (PG) serglycin, were stably transfected with cDNA for human serglycin fused to a polyhistidine tag (His-tag). Clones with different levels of serglycin mRNA expression were generated. One clone with lower and one with higher serglycin mRNA expression were selected for this study. 35S-labelled serglycin in cell fractions and conditioned media was isolated using HisTrap affinity chromatography. Serglycin could also be detected in conditioned media using western blotting. To investigate the possible importance of serglycin linked to protease secretion, enzyme activities using chromogenic substrates and zymography were measured in cell fractions and serum-free conditioned media of the different clones. Cells were cultured in both the absence and presence of phorbol 12-myristate 13-acetate (PMA). In general, enzyme secretion was strongly enhanced by treatment with PMA. Our analyses revealed that the clone with the highest serglycin mRNA expression, level of HisTrap isolated 35S-labelled serglycin, and amount of serglycin core protein as detected by western blotting, also showed the highest secretion of proteases. Transfection of serglycin into MDCK cells clearly leads to changes in secretion levels of secreted endogenous proteases, and could provide further insight into the biosynthesis and secretion of serglycin and potential partner molecules. [source]


    Metalloproteinase-9 in circulating monocytes in pulmonary hypertension

    FUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 4 2006
    Caroline Cantini-Salignac
    Abstract The role of matrix metalloproteinases (MMPs) in pulmonary hypertension (PH) is complex as MMPs are involved in both the vascular and cardiac remodelling associated with PH. To gain insight into this problem, monocytes were isolated from pulmonary arterial blood in patients suffering from PH, related to chronic obstructive pulmonary disease (n = 6), chronic pulmonary thromboembolism (n = 3) or pulmonary arterial hypertension (n = 8). The severity of PH was associated with decreases in cardiac index (CI) and mixed venous blood oxygen saturation (SO2), and an increase in right atrial pressure (). Monocyte pro-MMP-9 content (zymography) was positively correlated with SO2 (r = 0.73, P < 0.05) and CI (r = 0.66, P < 0.05), and negatively with (r = 0.54, P < 0.05); there was no significant correlation with pulmonary vascular resistance. In conclusion, the pro-MMP-9 content of circulating monocytes was lower in the more severe forms of PH which showed heart failure suggesting that such MMP enzymatic activity reflects heart failure following pulmonary vascular and myocardial remodelling in PH. [source]


    Microglial expression of ,v,3 and ,v,5 integrins is regulated by cytokines and the extracellular matrix: ,5 Integrin null microglia show no defects in adhesion or MMP-9 expression on vitronectin

    GLIA, Issue 7 2009
    Richard Milner
    Abstract As the primary immune effector cells in the CNS, microglia play a central role in regulating inflammation. The extracellular matrix (ECM) protein vitronectin is a strong inducer of microglial activation, switching microglia from a resting into an activated potentially destructive phenotype. As the activating effect of vitronectin is mediated by ,v integrins, the aim of the current study was to evaluate the requirement of the ,v,5 integrin in mediating microglial adhesion and activation to vitronectin, by studying these events in ,5 integrin-null murine microglia. Surprisingly, ,5 integrin null microglia were not defective in adhesion to vitronectin. Further analysis showed that microglia express the ,v,3 integrin, in addition to ,v,5. Flow cytometry revealed that microglial ,v integrin expression is regulated by cytokines and ECM proteins. ,v,3 integrin expression was downregulated by IFN-,, TNF, LPS, and TGF-,1. ,v,5 expression was also reduced by IFN-,, TNF, and LPS, but strongly increased by the antiactivating factors TGF-,1 and laminin. Gel zymography revealed that ,5 integrin null microglia showed no deficiency in their expression of matrix metalloproteinase (MMP)-9 in response to vitronectin. Taken together, these data show that microglia express two different ,v integrins, ,v,3 and ,v,5, and that expression of these integrins is independently regulated by cytokines and ECM proteins. Furthermore, it reveals that the ,v,5 integrin is not essential for mediating microglial adhesion and MMP-9 expression in response to vitronectin. © 2008 Wiley-Liss, Inc. [source]


    Matrix metalloproteinase-2 is involved in myelination of dorsal root ganglia neurons

    GLIA, Issue 5 2009
    Helmar C. Lehmann
    Abstract Matrix metalloproteinases (MMPs) comprise a large family of endopeptidases that are capable of degrading all extracellular matrix components. There is increasing evidence that MMPs are not only involved in tissue destruction but may also exert beneficial effects during axonal regeneration and nerve remyelination. Here, we provide evidence that MMP-2 (gelatinase A) is associated with the physiological process of myelination in the peripheral nervous system (PNS). In a myelinating co-culture model of Schwann cells and dorsal root ganglia neurons, MMP-2 expression correlated with the degree of myelination as determined by immunocytochemistry, zymography, and immunosorbent assay. Modulation of MMP-2 activity by chemical inhibitors led to incomplete and aberrant myelin formation. In vivo MMP-2 expression was detected in the cerebrospinal fluid (CSF) of patients with Guillain-Barré syndrome as well as in CSF and sural nerve biopsies of patients with chronic inflammatory demyelinating polyneuropathy. Our findings suggest an important, previously unrecognized role for MMP-2 during myelination in the PNS. Endogenous or exogenous modulation of MMP-2 activity may be a relevant target to enhance regeneration in demyelinating diseases of the PNS. © 2008 Wiley-Liss, Inc. [source]


    Oxidized low-density lipoprotein induces matrix metalloproteinase-9 expression via a p42/p44 and JNK-dependent AP-1 pathway in brain astrocytes

    GLIA, Issue 1 2009
    Hui-Hsin Wang
    Abstract Upregulation of matrix metalloproteinases (MMPs), especially MMP-9, by oxidized low-density lipoprotein (oxLDL) is implicated in many inflammatory diseases including brain injury. However, the signaling mechanisms underlying oxLDL-induced MMP-9 expression in astrocytes largely remain unknown. Here we report that oxLDL induces expression of proMMP-9 via a MAPK-dependent AP-1 activation in rat brain astrocyte (RBA)-1 cells. Results revealed by gelatin zymography, RT-PCR, and Western blotting analyses showed that oxLDL-induced proMMP-9 gene expression was mediated through Akt, JNK1/2, and p42/p44 MAPK phosphorylation in RBA-1 cells. These responses were attenuated by inhibitors of PI3K (LY294002), JNK (SP600125), and p42/p44 MAPK (PD98059), or transfection with dominant negative mutants and short hairpin RNA. Moreover, we demonstrated that AP-1 (i.e., c-Fos/c-Jun) is crucial for oxLDL-induced proMMP-9 expression which was attenuated by pretreatment with AP-1 inhibitor (curcumin). The regulation of MMP-9 gene transcription by AP-1 was confirmed by oxLDL-stimulated MMP-9 luciferase activity which was totally lost in cells transfected with the AP-1 binding site-mutated MMP-9 promoter construct (mt-AP1-MMP-9). These results suggested that oxLDL-induced proMMP-9 expression is mediated through PI3K/Akt, JNK1/2, and p42/p44 MAPK leading to AP-1 activation. Understanding the regulatory mechanisms underlying oxLDL-induced MMP-9 expression in astrocytes might provide a new therapeutic strategy of brain injuries and diseases. © 2008 Wiley-Liss, Inc. [source]


    Autocrine motility factor enhances hepatoma cell invasion across the basement membrane through activation of ,1 integrins

    HEPATOLOGY, Issue 1 2001
    Takuji Torimura
    Autocrine motility factor/phosphohexose isomerase (AMF/PHI) is a cytokine that is linked to tumor invasion and metastasis. In hepatocellular carcinoma (HCC) tissues, hepatoma cells produce AMF/PHI and its receptor, Mr 78,000 glycoprotein (gp78), is strongly detected in hepatoma cells invading into the stroma and tumor thrombi in the portal vein. Here, we investigated the mechanism of hepatoma cell invasion through Matrigel induced by AMF/PHI using 3 hepatoma cell lines. Production of AMF/PHI, phosphorylation of MEK1/2, and Rho activity were investigated by immunoblotting. Expression of AMF/PHI and gp78 was observed by confocal fluorescence microscopy. The influence of AMF/PHI on activated integrin ,1 subunit expression was evaluated by flow cytometry. Changes in invasion, adhesion, and motility induced by AMF/PHI were evaluated using chemoinvasion, adhesion, and phagokinetic track motility assays. The effect of AMF/PHI on matrix metalloproteinase (MMP) secretion was evaluated by gelatin zymography. Hepatoma cells produced AMF/PHI and expressed gp78. Although AMF/PHI was ubiquitously detected, gp78 was strongly expressed in migrating cells. AMF/PHI induced up-regulation of activated integrin ,1 subunit expression. AMF/PHI stimulated hepatoma cell invasion through Matrigel, and stimulated the adhesion, motility, and MMP-2 secretion of hepatoma cells. The latter effects were suppressed by the function-blocking antibody for integrin ,1 subunit. AMF/PHI also enhanced Rho activity and the phosphorylation of MEK1 and MEK 2. Our results indicate that AMF/PHI enhances hepatoma cell invasion through Matrigel in an autocrine manner by stimulating the adhesion, motility, and MMP-2 secretion of these cells through activation of ,1 integrins. [source]


    Examination of the signal transduction pathways leading to upregulation of tissue type plasminogen activator by Porphyromonas endodontalis in human pulp cells

    INTERNATIONAL ENDODONTIC JOURNAL, Issue 12 2005
    F.-M. Huang
    Abstract Aim, To investigate the tissue type plasminogen activator (t-PA) activity in human pulp cells stimulated with Porphyromonas endodontalis (P. endodontalis) in the absence or presence of p38 inhibitor SB203580, mitogen-activated protein kinase kinase (MEK) inhibitor U0126 and phosphatidylinositaol 3-kinase (PI3K) inhibitor LY294002. Methodology, The supernatants of P. endodontalis were used to evaluate t-PA activity in human pulp cells using casein zymography and enzyme-linked immunosorbent assay (ELISA). Furthermore, to search for possible signal transduction pathways, SB203580, U0126 and LY294002 were added to test how they modulated the t-PA activity. Results, The main casein secreted by human pulp cells migrated at 70 kDa and represented t-PA. Secretion of t-PA was found to be stimulated with P. endodontalis during 2-day cultured period (P < 0.05). From the results of casein zymography and ELISA, SB203580 and U0126 significantly reduced the P. endodontalis stimulated t-PA production respectively (P < 0.05). However, LY294002 lacked the ability to change the P. endodontalis stimulated t-PA production (P > 0.05). Conclusions,Porphyromonas endodontalis enhances t-PA production in human pulp cells, and the signal transduction pathways p38 and MEK are involved in the inhibition of t-PA. [source]


    Finasteride treatment alters MMP-2 and -9 gene expression and activity in the rat ventral prostate

    INTERNATIONAL JOURNAL OF ANDROLOGY, Issue 1 2010
    Flávia 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]


    Active MMP-2 effectively identifies the presence of colorectal cancer

    INTERNATIONAL JOURNAL OF CANCER, Issue 12 2009
    Mary 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]


    Expression of HYAL2 mRNA, hyaluronan and hyaluronidase in B-cell non-Hodgkin lymphoma: Relationship with tumor aggressiveness

    INTERNATIONAL JOURNAL OF CANCER, Issue 2 2005
    Philippe Bertrand
    Abstract Hyaluronidases and their substrate, hyaluronan (HA), were mainly explored in solid tumors but rarely in hematologic malignancies. While HA involvement was demonstrated in invasion and metastasis in most cases of solid tumors, the role of hyaluronidases in cancer progression remains controversial. One of the hyaluronidases, HYAL2, is suspected to be involved in the first step of HA degradation. In this work, HYAL2 mRNA, HA and total hyaluronidases expression were examined in lymphoma tissue extracts and correlated to the lymphoma subtype. Real-time RT-PCR was performed to evaluate HYAL2 mRNA. HA and hyaluronidase were assayed by enzyme-linked sorbent assay. Our results showed that HYAL2 mRNA expression was correlated to lymphoma diagnosis (p = 6 × 10,3) and was significantly lower in high-grade lymphoma, i.e., diffuse large B-cell diffuse lymphomas (DLBCLs). Several forms of hyaluronidase were detected by zymography and total hyaluronidase activity detected in tissue extracts was not significantly different according to tumor grade. HA levels also correlated to lymphoma subtype (p = 1 × 10,5) and were higher in DLBCLs. Moreover, HYAL2 mRNA and HA expressions were inversely correlated (p = 0.035). HYAL2 gene is localized on chromosome 3p21, which contains candidates tumor suppressor genes. Our results suggest that HYAL2 may have a prognostic significance in lymphomas and an antioncogenic activity. Conversely, HA overexpression in high-grade lymphomas is in favor of its involvement in tumor development and could provide a useful target for lymphoma therapy using HA-binding peptides. [source]


    Development of effects of plant extracts on the activity and expression of UVA-induced MMPs (matrix metalloproteases)

    INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 6 2004
    D.-H. Lee
    The effects of several natural products on in vitro MMP-1 activity and UVA-induced MMP-1 synthesis in human dermal fibroblast (HDF) cultures were studied with the aim of developing novel anti-aging agents from natural sources. We measured MMP-1 activities by fluorescence assay using gelatin as substrates. In addition, UVA-induced MMP-1 expression was analyzed by enzyme-linked immunosorbent assay (ELISA) and gelatin-based zymography in HDF cultures, and RT-PCR techniques were used. The results showed a strong inhibitory effect of the extracts of Dicentra spectabilis and of the flower buds of Tussilago farfara. In a concentration of 0.05% (w/v), the extracts of the flower buds of Tussilago farfara and of Dicentra spectabilis inhibited MMP-1 activity by 92 and 87% respectively. At 0.1% (w/v), the extracts of the flower buds of Tussilago farfara and of Dicentra spectabilis suppressed the UVA-induced expression of MMP-1 by an amount similar to that with Vitamin C 200 ,m. These results suggest that the extracts of Dicentra spectabilis and of the flower buds of Tussilago farfara effectively protect skin from UV-induced photoaging. Therefore, the extracts are thought to have potential as effective raw materials for anti-aging cosmetics. [source]


    Upregulation of MMP-9/TIMP-1 enzymatic system in eosinophilic meningitis caused by Angiostrongylus cantonensis

    INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 2 2005
    Ke-Min Chen
    Summary Proteolysis depends on the balance between the proteases and their inhibitors. Matrix metalloproteinase-9 (MMP-9) and its specific inhibitors, tissue inhibitors of metalloproteinases (TIMP), contribute to eosinophilic inflammatory reaction in the subarachnoid space of the Angiostrongylus cantonensis -infected mice. The expression of MMP-9 in cerebrospinal fluid (CSF) was significantly increased in mice with eosinophilic meningitis, compared to that in uninfected ones. However, the TIMP-1 levels were unchanged and remained at basal levels at all time points, even in uninfected mice. Elevated MMP-9 mRNA expression coincided with protein levels and proteolytic activity, as demonstrated by means of positive immunoreactivity and gelatin zymography. CSF protein contents correlated significantly with MMP-9 intensity and CSF eosinophilia. In addition, immunohistochemistry demonstrated MMP-9 and TIMP-1 localization in eosinophils and macrophages. When the specific MMP inhibitor, GM6001, was added, MMP-9 enzyme activity was reduced by 45.4%. The percentage of eosinophil increased significantly upon the establishment of infection, but subsided upon inhibition. These results show that MMP-9/TIMP-1 imbalance in angiostrongyliasis may be associated with eosinophilic meningitis. [source]


    Sucrose phosphorylase of the rumen bacterium Pseudobutyrivibrio ruminis strain A

    JOURNAL OF APPLIED MICROBIOLOGY, Issue 3 2009
    A. Kasperowicz
    Abstract Aims:, To verify the taxonomic affiliation of bacterium Butyrivibrio fibrisolvens strain A from our collection and to characterize its enzyme(s) responsible for digestion of sucrose. Methods and Results:, Comparison of the 16S rRNA gene of the bacterium with GenBank showed over 99% sequence identity to the species Pseudobutyrivibrio ruminis. Molecular filtration, native electrophoresis on polyacrylamide gel, zymography and thin layer chromatography were used to identify and characterize the relevant enzyme. An intracellular sucrose phosphorylase with an approximate molecular mass of 52 kDa exhibiting maximum activity at pH 6·0 and temperature 45°C was identified. The enzyme was of inducible character and catalysed the reversible conversion of sucrose to fructose and glucose-1-P. The reaction required inorganic phosphate. The Km for glucose-1-P formation and fructose release were 3·88 × 10,3 and 5·56 × 10,3 mol l,1 sucrose, respectively , while the Vmax of the reactions were ,0·579 and 0·9 ,mol mg protein,1 min,1. The enzyme also released free glucose from glucose phosphate. Conclusion:,Pseudobutyrivibrio ruminis strain A utilized sucrose by phosphorolytic cleavage. Significance and Impact of the Study:, Bacterium P. ruminis strain A probably participates in the transfer of energy from dietetary sucrose to the host animal. [source]


    Matrix metalloproteinases 2 and 9 in central nervous system and their modification after vanadium inhalation

    JOURNAL OF APPLIED TOXICOLOGY, Issue 6 2008
    L. Colín-Barenque
    Abstract Vanadium (V) derivatives are well-known environmental pollutants and its toxicity has been related with oxidative stress. Toxicity after vanadium inhalation on the substantia nigra, corpus striatum, hippocampus and ependymal epithelium was reported previously. The purpose of this study was to analyse the role of matrix metalloproteinases 2 (MMP-2) and 9 (MMP-9) in the changes observed in brain tissue after chronic V inhalation. Mice were exposed to vaporized, vanadium pentoxide 0.02 m in deionized water for 1 h twice a week, and killed at 1 h, 1, 2 and 4 weeks after exposure. The brain was removed and the olfactory bulb, prefrontal cortex, striatum and hippocampus were dissected and the MMP content was obtained by zymography. The results showed that MMP-9 increased in all the structures at the end of the exposure, although in the hippocampus this increment was evident after 1 week of exposure. When MMP-2 was analysed in the olfactory bulb and prefrontal cortex it remained unchanged throughout the whole exposure, while in the hippocampus it increased at week 4, while in the striatum MMP-2 increased from the second week only, through the whole experiment. These results demonstrate that V increased MMPs in different structures of the CNS and this change might be associated with the previously reported modifications, such as dendritic spine loss and neuronal cell death. The modifications in MMPs could be related with blood,brain barrier (BBB) disruption which was reported previously. Oxidative stress might also be involved in the activation of these gelatinases as part of the different mechanisms which take place in V toxicity in the CNS. Copyright © 2007 John Wiley & Sons, Ltd. [source]


    Atypical protein kinase C activity is required for extracellular matrix degradation and invasion by Src-transformed cells

    JOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2009
    Elena M. Rodriguez
    Atypical protein kinase C (aPKC) isoforms have been shown to mediate Src-dependent signaling in response to growth factor stimulation. To determine if aPKC activity contributes to the transformed phenotype of cells expressing oncogenic Src, we have examined the activity and function of aPKCs in 3T3 cells expressing viral Src (v-Src). aPKC activity and tyrosine phosphorylation were found to be elevated in some but not all clones of mouse fibroblasts expressing v-Src. aPKC activity was inhibited either by addition of a membrane-permeable pseudosubstrate, by expression of a dominant-negative aPKC, or by RNAi-mediated knockdown of specific aPKC isoforms. aPKC activity contributes to morphological transformation and stress fiber disruption, and is required for migration of Src-transformed cells and for their ability to polarize at the edge of a monolayer. The , isoform of aPKC is specifically required for invasion through extracellular matrix in Boyden chamber assays and for degradation of the extracellular matrix in in situ zymography assays. Tyrosine phosphorylation of aPKC, is required for its ability to promote cell invasion. The defect in invasion upon aPKC inhibition appears to result from a defect in the assembly and/or function of podosomes, invasive adhesions on the ventral surface of the cell that are sites of protease secretion. aPKC was also found to localize to podosomes of v-Src transformed cells, suggesting a direct role for aPKC in podosome assembly and/or function. We conclude that basal or elevated aPKC activity is required for the ability of Src-transformed cells to degrade and invade the extracellular matrix. J. Cell. Physiol. 221: 171,182, 2009. © 2009 Wiley-Liss, Inc [source]


    Downregulation of a rheumatoid arthritis-related antigen (RA-A47) by ra-a47 antisense oligonucleotides induces inflammatory factors in chondrocytes

    JOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2003
    Takako Hattori
    Previously we have shown that the expression of RA-A47 (rheumatoid arthritis-related antigen) which is identical to HSP47, a collagen-binding chaperon, is downregulated in chondrocytes by tumor necrosis factor , (TNF,). RA-A47 was also found on the surface of chondrocytes where it is recognized as an antigen in the serum of rheumatoid arthritis (RA) patients. Its translocation to the cell surface from endoplasmic reticulum membrane where it is normally located was also enhanced by TNF,. To understand the significance of RA-A47 downregulation in chondrocytes independent from other effects of TNF,, we used an antisense oligonucleotide approach and investigated the effect of this treatment on the expression of molecules related to matrix degradation and production of growth factors for chondrocytic, endothelial, and synovial cells. Here we show that treatment of rabbit chondrocyes and human chondrosarcoma cells HCS-2/8 by ra-a47 antisense S -oligonucleotides significantly reduced the expression of ra-a47 both at mRNA and protein level. Interestingly, this TNF,-independent RA-A47 downregulation was associated with a strong induction of matrix metalloproteinase (MMP)-9 mRNA and inducible NO synthase (iNOS) mRNA. The induction of active-type MMP-9 was further detected by gelatin zymography. Under the same conditions, the release of basic fibroblast growth factor (bFGF) and connective tissue growth factor (CTGF) from HCS-2/8 cells into the conditioned medium (CM) was strongly enhanced. These effects were not a result of TNF, upregulation, since the ra-a47 antisense oligonucleotide treatment did not enhance TNF, synthesis. These observations indicate that downregulation of RA-A47 induces TNF,-independent cartilage-degrading pathways involving iNOS and MMP-9. Furthermore, the stimulation of bFGF and CTGF release from chondrocytes may stimulate the proliferation of adjacent endothelial and/or synovial cells. J. Cell. Physiol. 197: 94,102, 2003© 2003 Wiley-Liss, Inc. [source]


    Analysis of the signal transduction pathway of nickel-induced matrix metalloproteinase-2 expression in the human keratinocytes in vitro: preliminary findings

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 6 2007
    Brunella Perfetto
    Background:, Nickel can induce cellular and nuclear damages responsible for chronic diseases, like allergic contact dermatitis (ACD). We previously showed that matrix metalloproteinase-2 (MMP-2) gene expression was induced by nickel in nontumorigenic human keratinocytes cell line (HaCat). Objective:, To investigate the signal transduction pathways involved in gelatinolytic activity induced in HaCat under nickel stimulation. Methods:, We analyzed the involvement of protein kinase A (PKA), protein kinase C (PKC), tyrosine kinase (PTK), nuclear factor-kB (NF-kB) and activator protein-1 (AP-1) using specific inhibitors (H89, calphostin C, genistein, carpain and curcumin) by electrophoretic mobility shift assay, reverse transcription-polymerase chain reaction and gelatin zymography. Results:, Our results indicate that nickel-induced MMP-2 production was inhibited with PTK, PKC and AP-1 specific inhibitors. Moreover, both PKA and NF-kB were not involved in nickel pathway. Conclusions:, Using HaCat, we showed that curcumin and genistein can revert nickel-induced MMP-2 upregulation. Whether the use of PTK and AP-1 inhibitors has therapeutic ramifications in the management of ACD remains to be investigated. [source]


    Induced hypothyroidism accelerates the regression of liver fibrosis in rats

    JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 12 2007
    Rafael Bruck
    Abstract Background and Aim:, It has been shown in previous studies that hypothyroidism prevents the development of liver fibrosis in bile duct ligated rats and in rats chronically treated with thioacetamide (TAA). In recent years, regression of liver fibrosis (occurring spontaneously or during treatment) has been demonstrated in rodent models such as bile duct ligation and CCl4 administration. Therefore, in the present study, the potential therapeutic effect of hypothyroidism on liver fibrosis was investigated. Methods:, Liver fibrosis was induced in rats by administration of TAA (200 mg/kg, i.p., twice weekly) for 12 weeks. Hypothyroidism was then induced by either methimazole (0.04%) or propylthiouracil (0.05%) administered in drinking water for 8 weeks. Control euthyroid rats received normal drinking water. Hypothyroidism was confirmed by a significant elevation of serum thyroid-stimulating hormone levels. Results:, Eight weeks after the cessation of TAA administration, spleen weight, histological score of liver fibrosis, and hepatic hydroxyproline content were significantly lower in both groups of hypothyroid rats as compared to euthyroid controls (P < 0.001). In vitro studies using the rat hepatic stellate cell line HSC-T6 using northern blot analysis and zymography, respectively, showed that high concentrations of triiodotyronine (T3) enhanced transforming growth factor (TGF)-,-induced collagen I gene expression, and reduced metalloproteinase (MMP)-2 secretion, implying that reducing the levels of T3 may contribute to resolution of fibrosis. Additionally, low T3 concentration inhibited HSC-T6 proliferation. Conclusion:, Pharmacologically induced hypothyroidism accelerates the resolution of liver fibrosis in rats. This beneficial effect may in part be due to prevention of T3 -induced stimulation of collagen synthesis and reduction of MMP-2 secretion. [source]


    AUF-1 mediates inhibition by nitric oxide of lipopolysaccharide-induced matrix metalloproteinase-9 expression in cultured astrocytes

    JOURNAL OF NEUROSCIENCE RESEARCH, Issue 2 2006
    Wenlan Liu
    Abstract Neuroinflammatory diseases are associated with increased production of matrix metalloproteinase-9 (MMP-9) and excessive generation of nitric oxide (NO). NO hasbeen reported to have variable effects on MMP-9 gene expression and activation in various cell types. Inthe present study, we investigated the effect of NOon MMP-9 expression in primary cortical astrocytes. Zymography and real-time PCR showed that lipopolysaccharide (LPS) dramatically increased latent MMP-9 gelatinolytic activity and MMP-9 mRNA expression. By using the NO donor DETA NONOate, we observed a dose-dependent inhibition of MMP-9 induction by LPS. Active forms of MMP-9 were not found by zymography after NO treatment. The MEK1/2 inhibitor U0126 completely inhibited LPS-induced MMP-9, which was partially inhibited by the p38 MAPK inhibitor SB203580. NO had no effect on LPS-stimulated ERK1/2 and p38 MAPK activation, suggesting that the inhibitory action of NO occurs downstream of MAPK cascades. Real-time PCR analysis showed that NO accelerated the degradation of MMP-9 mRNA after LPS induction. Western blotting and pull-down assay demonstrated that NO increased AUF-1 expression as well as its specific binding to the MMP-9 gene 3,-untranslated region. Knockdown of AUF-1 with siRNA partially reversed the inhibitory action of NO on LPS-stimulated MMP-9 induction. We conclude that NO does not activate MMP-9 in astrocyte cultures but reduces LPS-induced MMP-9 expression via accelerating MMP-9 mRNA degradation, which is partially mediated by AUF-1. Our results suggest that elevated NO concentrations may suppress MMP-9 and restrict the inflammatory response in neurodegenerative diseases. © 2006 Wiley-Liss, Inc. [source]


    Areca nut extract-treated gingival fibroblasts modulate the invasiveness of polymorphonuclear leukocytes via the production of MMP-2

    JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 1 2009
    Hsuan-Hsuan Lu
    Background:, Areca nut chewing is associated with an increase in the incidence of oral neoplastic or inflammatory diseases. Aberrations in matrix metalloprotease (MMP) expression are associated with the pathogenesis of oral diseases. This study investigated the potential effects of areca nut extract (ANE) on human gingival fibroblasts and the consequential impacts on inflammatory pathogenesis. Methods:, Analyses of senescence marker, cell viability, changes of the cell cycle, and cell granularity in gingival fibroblasts together with an assessment of the invasiveness of polymorphonuclear (PMN) leukocytes after treatment with the supernatant of ANE-treated gingival fibroblasts were performed to characterize the phenotypic impacts. Western blotting and gelatin zymography were used to assay the expression and activity of MMP-2. Results:, Chronic subtoxic (<10 ,g/ml) ANE treatment resulted in premature growth arrest, appearance of senescence-associated ,-galactosidase activity and various other senescence-associated phenotypes in gingival fibroblasts. Gingival fibroblasts established from older individuals had a higher propensity to become ANE-induced senescent gingival fibroblasts. An activation of MMP-2 was identified in senescent cells. PMN leukocytes treated with the supernatant of ANE-induced senescent cells exhibited a significant increase in invasiveness, which was abrogated by both a MMP-2 blocker and a MMP-2 nullifying antibody. Conclusions:, This study provides evidence whereby MMP-2 secreted from ANE-induced senescent gingival fibroblasts would facilitate the invasiveness of PMN leukocytes, which could be associated with the oral inflammatory process in areca chewers. [source]