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1.
Matrix metalloproteinases (MMPs) are a family of host-derived enzymes involved in the turnover of extracellular matrix (ECM) molecules and the processing of cytokines, chemokines and growth factors. We have previously reported that global inhibition of MMP in Chlamydia muridarum urogenital tract infection of susceptible strains of female mice impeded ascension of C. muridarum into the upper genital tract, blunted acute inflammatory responses and reduced the rate of formation of chronic disease. Because we have also observed that MMP-9 (also known as gelatinase B) is expressed in relatively large quantities in susceptible strains of mice in response to infection during acute phases of infection, we explored this further in a more selected fashion. We infected MMP-9 gene knockout mice and wild type controls intravaginally with C. muridarum. Both groups of mice had similar isolation rates from the lower urogenital tract but the absence of MMP-9 resulted in a slightly lower isolation rate in the upper genital tract, blunted acute inflammatory indices in the affected tissues and a reduced rate of formation of hydrosalpinx-a surrogate marker of infertility. These results imply that MMP-9 is involved in pathogenesis of chlamydial infection in this model possibly by amplifying inflammatory responses.  相似文献   

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【目的】探讨鼠衣原体(Chlamydia muridarum)对小鼠溃疡性结肠炎的作用。【方法】取15只雌性C57BL/6J小鼠随机分为3组,每组5只动物,分别为空白对照组(Control)、肠炎模型组(DSS)、实验组(CM+DSS)。选取CM+DSS组小鼠予以2×105 IFU的鼠衣原体灌胃处理,并在其感染后第29天开始,给予DSS组和CM+DSS组的小鼠2%DSS饮水,持续5d,每天监测小鼠体重和肠炎疾病评分,实验结束后检测小鼠结肠长度和结肠组织炎性改变。【结果】肠炎模型组的小鼠均表现出典型的肠炎症状(包括体重减轻、肠炎疾病评分、结肠长度和组织炎性改变);而经鼠衣原体预处理的小鼠(CM+DSS组)肠炎症状显著减轻,表现在肠炎疾病评分降低,体重和结肠长度有所恢复,肠组织炎性损伤减轻。【结论】鼠衣原体对DSS诱导的小鼠溃疡性结肠炎具有改善作用。  相似文献   

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The hepatitis B virus (HBV) is a major cause of human liver disease, including hepatocellular carcinoma (HCC). The prognosis for HCC is largely dependent on the clinicopathological characteristics regarding invasion and metastasis. Enhanced matrix metalloproteinase-9 (MMP-9) expression has been implicated as playing an important role in metastasis and invasion of HCC. However, the relationship between HBV infection and MMP-9 expression in HCC is currently poorly understood. We report here on a study of the levels of MMP-9 and MMP-2 expression in human fetal liver tissue, rat liver tissue, and Chang, HepG2, and Hep3B cells by gelatin zymography. Among these sources, Hep3B cells, which contain the integrated hepatitis B viral genome, continuously secrete the hepatitis B viral surface antigen, and express HBV genomic RNA, expressed high levels of proMMP-9, and a small amount of active MMP-9 was detected in Hep3B cells as assayed by zymography. We investigated the issue of whether HBV infection affects MMP-9 expression, which is known to play an important role in HCC invasion and metastasis. As a first step, human fetal hepatocyte (HFH) and HepG2 (HCC origin, HBV not detected) cells were subjected to infection with HBV, and the resulting infected cells successfully established are hereafter referred to as HFH-T2 and HepG2-HBV. The expression of MMP-9 was upregulated by the infected HBV in HFH-T2 and HepG2-HBV cells, as assayed by zymography, Northern blot, and Western blot analysis, and small amounts of active MMP-9 were detected in HFH-T2 and HepG2-HBV cells as assayed by zymography. The activation of the immature proMMP-9 to the mature MMP-9 could be induced by plasmin treatment. The activation of proMMP-9 was increased to a greater extent with plasmin treatment than without plasmin in HFH-T2 and HepG2-HBV cells but the addition of recombinant TIMP-1 inhibited the activation of proMMP-9. Finally, the addition of plasmin to the invasion assay using Matrigel resulted in an increase in invasiveness of HFH-T2 and HepG2-HBV cells, as well as MMP-9 activation, but the treatment with TIMP-1 inhibited the invasiveness of HFH-T2 and HepG2-HBV cells as well as MMP-9 activation. We conclude from these findings that HBV infection of hepatocytes and HepG2 cells affected the upregulation of MMP-9 expression and MMP-9 activation and, thus, increased the invasion potential by plasmin. To our knowledge, this is a first report showing that an HBV infection is linked to the upregulation of MMP-9 in HCC.  相似文献   

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BACKGROUND Matrix metalloproteinases(MMPs),including MMP-9,are an integral part of the immune response and are upregulated in response to a variety of stimuli.New details continue to emerge concerning the mechanistic and regulatory pathways that mediate MMP-9 secretion.There is significant evidence for regulation of inflammation by dimethyl sulfoxide(DMSO)and 3',5'-cyclic adenosine monophosphate(cAMP),thus investigation of how these two molecules may regulate both MMP-9 and tumor necrosis factorα(TNFα)secretion by human monocytes was of high interest.The hypothesis tested in this study was that DMSO and cAMP regulate MMP-9 and TNFαsecretion by distinct mechanisms.AIM To investigate the regulation of lipopolysaccharide(LPS)-stimulated MMP-9 and tumor necrosis factorαsecretion in THP-1 human monocytes by dimethyl sulfoxide and cAMP.METHODS The paper describes a basic research study using THP-1 human monocyte cells.All experiments were conducted at the University of Missouri-St.Louis in the Department of Chemistry and Biochemistry.Human monocyte cells were grown,cultured,and prepared for experiments in the University of Missouri-St.Louis Cell Culture Facility as per accepted guidelines.Cells were treated with LPS for selected exposure times and the conditioned medium was collected for analysis of MMP-9 and TNFαproduction.Inhibitors including DMSO,cAMP regulators,and anti-TNFαantibody were added to the cells prior to LPS treatment.MMP-9 secretion was analyzed by gel electrophoresis/western blot and quantitated by ImageJ software.TNFαsecretion was analyzed by enzyme-linked immuno sorbent assay.All data is presented as the average and standard error for at least 3 trials.Statistical analysis was done using a two-tailed paired Student t-test.P values less than 0.05 were considered significant and designated as such in the Figures.LPS and cAMP regulators were from Sigma-Aldrich,MMP-9 standard and antibody and TNFαantibodies were from R&D Systems,and amyloid-βpeptide was from rPeptide.RESULTS In our investigation of MMP-9 secretion from THP-1 human monocytes,we made the following findings.Inclusion of DMSO in the cell treatment inhibited LPSinduced MMP-9,but not TNFα,secretion.Inclusion of DMSO in the cell treatment at different concentrations inhibited LPS-induced MMP-9 secretion in a dosedependent fashion.A cell-permeable cAMP analog,dibutyryl cAMP,inhibited both LPS-induced MMP-9 and TNFαsecretion.Pretreatment of the cells with the adenylyl cyclase activator forskolin inhibited LPS-induced MMP-9 and TNFαsecretion.Pretreatment of the cells with the general cAMP phosphodiesterase inhibitor IBMX reduced LPS-induced MMP-9 and TNFαin a dose-dependent fashion.Pre-treatment of monocytes with an anti-TNFαantibody blocked LPSinduced MMP-9 and TNFαsecretion.Amyloid-βpeptide induced MMP-9 secretion,which occurred much later than TNFαsecretion.The latter two findings strongly suggested an upstream role for TNFαin mediating LPS-stimulate MMP-9 secretion.CONCLUSION The cumulative data indicated that MMP-9 secretion was a distinct process from TNFαsecretion and occurred downstream.First,DMSO inhibited MMP-9,but not TNFα,suggesting that the MMP-9 secretion process was selectively altered.Second,cAMP inhibited both MMP-9 and TNFαwith a similar potency,but at different monocyte cell exposure time points.The pattern of cAMP inhibition for these two molecules suggested that MMP-9 secretion lies downstream of TNFαand that TNFαmay a key component of the pathway leading to MMP-9 secretion.This temporal relationship fit a model whereby early TNFαsecretion directly led to later MMP-9 secretion.Lastly,antibody-blocking of TNFαdiminished MMP-9 secretion,suggesting a direct link between TNFαsecretion and MMP-9 secretion.  相似文献   

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A divergent synthesis of nobiletin metabolites was developed through highly oxygenated acetophenone derivative. We used commercially available methyl 3,4,5-trimethoxybenzoate as a starting material for concise preparation of the key intermediate, 2′-hydroxy-3′,4′,5′,6′-tetramethoxyacetophenone (I). These metabolites showed strong inhibitory activity against matrix metalloproteinase-9 production in human lens epithelial cells.  相似文献   

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Matrix metalloproteinase-9 (MMP-9) associates with cancer cell invasion and metastasis. CL1-5 cells, a human lung adenocarcinoma cell line, expressed an elevated level of MMP-9 and exhibited a highly invasive and metastatic ability. By Matrigel assay and gelatinase zymography, the topoisomerase II poison GL331 was found to dose-dependently inhibit the invasiveness and the level of secreted MMP-9 of CL1-5 cells. Northern blot analysis indicated that cellular MMP-9 mRNA level was decreased after GL331 treatment. Furthermore, GL331-induced down-regulation of mmp-9 gene promoter was demonstrated by using a luciferase reporter gene driven by the -216 to -13 region of the mmp-9 gene promoter cloned from CL1-5 cells. By PCR amplification and gel electrophoresis, we found that GL331 caused shortening of the -216 to -13 region of the mmp-9 promoter. Direct sequencing analysis revealed that the number of d(CA) was reduced from 24 to 18 at the microsatellite d(CA) repeat region of the mmp-9 promoter. The CL1-5 cells transfected with the luciferase reporter containing 18 d(CA)s expressed only 53% of those when the reporter contained 24 d(CA)s. The promoter region of mmp-9 gene contains other positive regulatory elements, such as TRE and kappaB. We found that GL331 did not significantly influence the luciferase activity driven by TRE or kappaB. Taken together, these data suggested that GL331 inhibited MMP-9 mRNA expression at least partly through the selective induction of shortening of microsatellite d(CA) repeats. This is the first report that an anti-cancer agent can inhibit mmp-9 gene expression by inducing microsatellite DNA shortening.  相似文献   

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It has previously been shown that matrix metalloproteinase-9 (MMP-9) levels, originating from macrophages, are considerably increased in human Helicobacter pylori-associated gastritis. Here, the early kinetics of the MMP-9 response resulting from Helicobacter infection in C57BL/6 and MMP-9 knock-out mice using the murine Helicobacter felis model were examined. H. felis infection induced severe gastritis in the murine stomach at just 2 weeks after infection. Before gastritis, an increase was observed in MMP-9-positive cells detected by immunohistochemistry in the basal lamina propria. This finding was corroborated by gelatin zymography of stomach samples. As the gastritis increased so did the concentration of MMP-9 and the incidence of gastric MMP-9-positive cells, their location corresponding to that of macrophages. In contrast, systemic levels of MMP-9 remained unchanged. When MMP-9-deficient mice were infected with H. felis, no significant difference in gastritis development was detected compared with disease development in wild-type animals. We conclude that MMP-9 production is an early event in the response to gastric Helicobacter infection, a feature that may favor the recruitment of immune cells early during infection. At later stages, however, the increased levels of MMP-9 may damage the integrity of the stomach mucosa.  相似文献   

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基质金属蛋白酶是一类可降解细胞外基质的蛋白酶,基质金属蛋白酶-2和-9为明胶酶,可降解细胞外基质中的胶原蛋白及弹性蛋白,其动态平衡对维持细胞外基质的稳定具有重要意义。主动脉的细胞外基质是主动脉中层重要的组成部分,细胞外基质成分的改变可导致主动脉中层结构的损伤,在主动脉疾病的发生、发展过程中起着重要作用。主动脉基质金属蛋白酶-2和-9的表达失衡可引起主动脉中层细胞外基质的降解,导致主动脉中层结构的损伤,从而促进主动脉疾病的发生。同时,主动脉疾病也可导致血浆中MMP-2、MMP-9浓度的升高。本文对近年来基质金属蛋白酶与主动脉疾病相关性的研究及进展作一综述,为心血管疾病发生机制的研究和治疗提供文献依据。  相似文献   

15.
Matrix metalloproteinase-2 (MMP-2) is an enzyme with proteolytic activity against matrix proteins, particularly basement membrane constituents. A single nucleotide polymorphism C-->T transition at -1306, which disrupts an Sp1-type promoter site (CCACC box), displayed a strikingly lower promoter activity with T allele. Our study investigated whether the MMP-2 -1306 C-->T polymorphism contributed to the development and progression of colorectal cancer in the Chinese population. One hundred twenty-six colorectal cancer patients and 126 age- and sex-matched controls were included in this study. PCR-based denaturing high performance liquid chromatography analysis and sequencing were used to determine the MMP-2 genotypes. MMP-2 expression of each genotype was analyzed in four colorectal cancer cell lines by semi-quantitative RT-PCR. The correlation between the genotypes and clinicopathological parameters among colorectal cancer cases was investigated. The results showed that the levels of MMP-2 mRNA expression in cell lines containing CC genotype were much higher compared with cell with CT genotype. The frequency of MMP-2 CC genotype was significantly higher in colorectal cancer patients when compared with controls (OR, 1.959; 95% CI, 1.055-3.637). Colorectal cancers with CC genotype were more common with serosa/adventitia layer involvement compared with CT+TT genotypes. Our data suggest that MMP-2 -1306 C-->T polymorphism may be associated with colorectal cancer development and invasion in the Chinese population.  相似文献   

16.
Fluorescein-isothiocyanate-conjugated monoclonal antibodies were used as a means to identify and enumerate Chlamydia trachomatis elementary bodies (EBs) fixed to the surface of either glass slides or polycarbonate membranes. EBs of all C. trachomatis serovars could be quantitated using these monoclonal antibodies which had specific reactivity with the major outer membrane protein. The results of experiments performed to compare the efficacy of each solid support substrate indicated no significant difference in performance or numerical values obtained for the concentration of EBs from the same preparation. The application of these specific approaches to EB quantitation will be dependent on the volume and other characteristics of the experimental preparation. The optimal use of glass slides was for the quantitation of purified EB preparations with high concentraton, whereas the filter may be used to concentrate dilute specimens. Both techniques were useful for estimating the concentration of EBs in sonicates prepared from infected host cells.  相似文献   

17.
We investigated whether thrombin, the final activator of coagulation cascade, regulates expression of matrix metalloproteinases (MMP)-9 in human monocytes.We show that thrombin stimulation induced MMP-9 secretion of monocytes dose- and time-dependently as revealed by gelatin zymography. Real-time RT-PCR and Western blot analysis demonstrated that thrombin up-regulated mRNA and protein levels of MMP-9. Pre-incubation with anti-protease-activated receptor (PAR)-1 or anti-PAR-3 antibody partially inhibited the thrombin-induced MMP-9 secretion. Simultaneous incubation with both showed synergistic effect, indicating the involvement of both receptors in this thrombin effect. BAPTA, a Ca2+ chelator, abolished the thrombin-induced MMP-9 secretion, indicating the requirement of Ca2+ mobilization in this process. Inhibition of thrombin-induced MMP-9 secretion by either MEK inhibitor or p38 kinase inhibitor revealed that the thrombin effect was mediated by both ERK1/2 and p38 pathways. The activation of NFκB by thrombin as demonstrated by electromobility shift assay was also shown to be critical to the thrombin-induced MMP-9 up-regulation.  相似文献   

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The drastic morphological changes of the tadpole are induced during the climax of anuran metamorphosis, when the concentration of endogenous thyroid hormone is maximal. The tadpole tail, which is twice as long as the body, shortens rapidly and disappears completely in several days. We isolated a cDNA clone, designated as Xl MMP-9TH, similar to the previously reported Xenopus laevis MMP-9 gene, and showed that their Xenopus tropicalis counterparts are located tandemly about 9 kb apart from each other in the genome. The Xenopus MMP-9TH gene was expressed in the regressing tail and gills and the remodeling intestine and central nervous system, and induced in thyroid hormone-treated tail-derived myoblastic cultured cells, while MMP-9 mRNA was detected in embryos. Three thyroid hormone response elements in the distal promoter and the first intron were involved in the upregulation of the Xl MMP-9TH gene by thyroid hormone in transient expression assays, and their relative positions are conserved between X. laevis and X. tropicalis promoters. These data strongly suggest that the MMP-9 gene was duplicated, and differentiated into two genes, one of which was specialized in a common ancestor of X. laevis and X. tropicalis to be expressed in degenerating and remodeling organs as a response to thyroid hormone during metamorphosis.  相似文献   

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The aberrant expression of matrix metalloproteinase-9 (MMP-9) is implicated in the invasion and angiogenesis process of brain tumor. This study has investigated the effects of curcumin on MMP-9 expression in human astroglioma cell lines. Curcumin significantly inhibited the MMP-9 enzymatic activity and protein expression that was induced by PMA. The inhibitory effect of curcumin on MMP-9 expression correlates with the decreased MMP-9 mRNA level and the suppression of MMP-9 promoter activity. The curcumin-mediated inhibition of MMP-9 gene expression appears to occur via NF-kappaB and AP-1 because their DNA binding activities were suppressed by curcumin. Furthermore, curcumin strongly repressed the PMA-induced phosphorylation of ERK, JNK, and p38 MAP kinase, which were dependent on the PKC pathway. Therefore, the inhibition of MMP-9 expression by curcumin might have therapeutic potential for controlling the growth and invasiveness of brain tumor.  相似文献   

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