Inhibition of matrix metalloproteinases suppresses the migration of skeletal muscle cells

Skeletal muscle satellite cells are quiescent stem cells that localized between the plasmalemma and the basement membrane of muscle fiber. When muscle is injured, satellite cells are activated, migrate to the injured site and contribute to the regeneration of muscle. However, little is known about the mechanism by which satellite cells migrate underneath the basement membrane. To clarify this, we investigated the effect of MMP inhibition on the migration of C2C12 muscle cells in vitro using a time-lapse imaging system. The migration speed of cells cultured with an MMP-inhibitor reagent was significantly lower (P<0.01) than the control cultured without an inhibitor reagent. The persistency index was significantly higher (P<0.01) in cells cultured with an inhibitor than in those without an inhibitor. Furthermore, MMP-3 knockdown cells migrated faster than control cells. These results strongly suggest that MMPs synthesized in skeletal muscle cells play an important role in the migration of these cells.     

HMGB1促进类风湿性关节炎滑膜成纤维细胞表达基质金属蛋白酶-13

目的:探讨高迁移率族蛋白1(HMGB1)能否激活类风湿性关节炎滑膜成纤维细胞(RASF)表达基质金属蛋白酶-13(MMP-13)。方法:HMGB1与RASF共孵育后,采用流式细胞术、实时RT-PCR、ELISA分别检测细胞周期和MMP-13的基因表达量以及蛋白表达水平。结果:1μg/ml HMGB1刺激滑膜成纤维细胞3小时,MMP-13 mRNA的表达明显增加;HMGB1刺激滑膜成纤维细胞48小时后MMP-13蛋白分泌增高,并且滑膜成纤维细胞增殖周期速度加快。结论:HMGB1可以激活滑膜成纤维细胞,使其增殖周期速度加快,MMP-13表达增加,提示HMGB1通过作用于滑膜成纤维细胞表达MMP-13加强关节结构破坏。     

Hypoxia suppresses the production of matrix metalloproteinases and the migration of human monocyte-derived dendritic cells

As most solid tumors are hypoxic, dendritic cells (DC) in solid tumors are also exposed to hypoxia. While many adaptation responses of tumor cells to hypoxia are known, it is yet to be determined how hypoxia affects the functions of DC. To explore the effects of hypoxia on the functions of DC, we compared the expression of surface markers, cytokines, chemokine receptors and matrix metalloproteinases (MMP) of human monocyte-derived DC (hmDC) differentiated under hypoxia to those differentiated under normoxia. Both groups of hmDC expressed similar levels of surface markers and cytokines. However, expression of MMP-9 and membrane type-1-MMP, as well as migrating activity, was significantly suppressed in hmDC differentiated under hypoxia compared with their normoxia counterparts. We also demonstrated that trichostatin A restored the production of MMP-9 in hmDC, under hypoxia. Collectively, our findings show that a hypoxic microenvironment suppresses the production of MMP in hmDC, most probably through the deacetylation of promoter regions of MMP, thus suppressing the migrating activity of hmDC. Our results suggest that the hypoxic microenvironment in solid tumor tissues may suppress the function of DC.     

Expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases in human chondrosarcomas

The aim of the present study was to characterise the ability of malignant chondrosarcomas to invade normal bone by analysing their production of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs). For this purpose 12 chondrosarcomas were investigated for the expression of mRNAs for several MMPs and all 4 TIMPs by Northern hybridisation, and for immunohistochemical localisation of the proteins. A characteristic finding of these analyses was increased expression of MMP-13, MMP-14 and TIMP-2 mRNAs in chondrosarcomas when compared with nonmalignant control samples. Individual chondrosarcomas also exhibited elevated levels of MMP-1, MMP-7 and MMP-9 mRNAs. The results of Northern hybridisations were supported by immunohistochemical stainings of the corresponding tumour areas for MMP-2, MMP-14 and TIMP-2, further suggesting that these may have prognostic value for determining whether individual chondrosarcomas are locally aggressive or have a probability of recurrence. Another finding of the present study was a marked heterogeneity in histologic appearance and gene expression of the chondrosarcomas, emphasising the importance of analysing several areas of these tumours to get representative results. These findings suggest that analysis of MMPs could be a useful diagnostic indicator in patients with cartilaginous tumours and could help in differentiating between a low-grade malignant chondrosarcoma and a benign growing enchondroma.     

Estrogen inhibits apoptosis and promotes CC motif chemokine ligand 13 expression on synovial fibroblasts in rheumatoid arthritis

Objective: Female patients have a higher prevalence of rheumatoid arthritis (RA) than male patients, suggesting that female sex hormones contribute to the disease pathogenesis. We herein report the findings of our study, which was conducted to clarify the role of estrogen in the pathogenesis of RA.

Methods: Cultured human synovial fibroblasts from a patient with RA were treated with 17β-estradiol (E₂). The effects of E₂ against cellular activation and apoptosis were evaluated. To identify the disease-related genes altered by E₂ treatment, the changes in the gene expression of the cells stimulated with and without E₂ were evaluated using a microarray analysis.

Results: We found that E₂-mediated cellular activation signaling through extracellular signal-regulated kinase (ERK)-1/2. E₂ possessed a suppressive effect for apoptosis and a promotive effect for tumor necrosis factor (TNF)-α-induced matrix metalloproteinase (MMP)-3 production on the synovial fibroblasts. A microarray analysis revealed that E₂ profoundly upregulated CC motif chemokine ligand 13 (CCL13) gene expression.

Conclusions: E₂ could mediate cellular activation signaling through ERK-1/2 on the synovial fibroblasts. The present data suggest that E₂ has adverse effects on the pathogenesis of RA as a result of unregulated cell death, increased TNF-α-induced MMP-3 production, and CCL13 overproduction, subsequently resulting in the disease progression of RA.     

The paradox of matrix metalloproteinases in infectious disease

Matrix metalloproteinases (MMPs) are a family of proteolytic enzymes that perform multiple roles in the normal immune response to infection. MMPs facilitate leucocyte recruitment, cytokine and chemokine processing, defensin activation and matrix remodelling. However, excess MMP activity following infection may lead to immunopathology that causes host morbidity or mortality and favours pathogen dissemination or persistence. Here, we review the normal functions of MMPs in immunity and then discuss viral and bacterial infections where excess MMP activity has been implicated in pathology, specifically examining HIV, HTLV-1, hepatitis B, endotoxin shock, Helicobacter pylori and Mycobacterium tuberculosis. Tissue destruction may be exacerbated further by bacterial-derived enzymes which activate the host pro-MMPs. Finally, the potential for therapeutic targeting of excess MMP activity in infection is considered.     

CD40 engagement modulates the production of matrix metalloproteinases by gingival fibroblasts

Chronic periodontitis is a destructive inflammatory disease linked with unbalanced production between matrix metalloproteinases (MMPs), such as interstitial collagenase (MMP-1) and stromelysin-1 (MMP-3) and their endogenous tissue inhibitors of MMPs (TIMPs). In addition to aberrant MMP-1 and MMP-3 expression, periodontal lesions are characterized by dense infiltrations of activated T lymphocytes which may interact with CD40-expressing gingival fibroblasts in the connective tissue via the CD40L-CD40 pathway. In this study we investigated whether CD40 cross-linking influenced MMP production by gingival fibroblasts. Therefore, we analysed the CD40L-induced MMP production by these fibroblasts in the presence of cytokines that are increased in periodontal lesions, such as IL-1β, tumour necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ). We show that CD40 ligation on gingival fibroblasts resulted in a decrease of their MMP-1 and MMP-3 production, while MMP-2 and TIMP-1 production were unaffected as determined by Western blot. This down-regulatory effect of CD40 engagement on MMP-1 and MMP-3 production by gingival fibroblasts was also present when MMP production was up-regulated by IL-1β and TNF-α or down-regulated by IFN-γ. These results suggest that CD40 ligation on gingival fibroblasts leads to a restraining of MMP-1 and MMP-3 production by gingival fibroblasts and thereby may be an important mechanism in the retardation of further periodontal tissue damage.     

Expression of matrix metalloproteinases and their inhibitors in human brain tumors

Sixty human brain tumors, classified according to the New World Health Organization (WHO) classification including, grade I schwannomas, meningiomas and pilocytic astrocytomas, grade II astrocytomas, grade III anaplastic astrocytomas, grade IV glioblastomas, grade III anaplastic oligodendrogliomas and grade IV glioblastomas and lung and melanoma metastases were analyzed for the expression of three matrix metalloproteinases (MMPs), two tissue inhibitors of MMPs (TIMPs) and for MMP activity. Some correlation was found between MMP expression and the degree of malignancy. Western blotting analysis revealed a more uniform pattern of distribution of MMP-2 (gelatinase A) than of MMP-9 (gelatinase B) and MMP-12 (metalloelastase) among tumors. MMP-9 levels were found to be significantly higher in grade III anaplastic astrocytomas and anaplastic oligodendrogliomas than those in grade I schwannomas and meningiomas. Anaplastic astrocytomas and Grade IV glioblastomas expressed significantly higher levels MMP-12 than grade I meningiomas. All sixty tumors showed a similar pattern of activity in zymography, proMMP-9 being the major species detected. Interestingly, TIMP-1 and TIMP-2 expression levels were especially low in tumors of grade II and grade III but significantly higher in tumors of grade I, particularly in schwannomas. Taken together, these data suggest that: 1) a balance between MMPs and TIMPs has an important role to play in human brain tumors; 2) TIMP expression may be valuable markers for tumor malignancy. This revised version was published online in July 2006 with corrections to the Cover Date.     

p38 MAPK及基质金属蛋白酶在心力衰竭病人心肌重构中的意义

目的: 探讨不同程度心力衰竭病人心肌组织丝裂素活化蛋白激酶（p38 MAPK）、基质金属蛋白酶家族（MMP-2、3、9）、细胞外基质（ECM）纤连蛋白（FN）表达与心肌重构的关系。方法: 选择因二尖瓣关闭不全心脏病接受二尖瓣置换术的心力衰竭病人39例，正常对照8例来自意外伤亡的器官捐献者。光镜检查心肌组织病理变化;免疫沉淀法检测心肌组织p38 MAPK磷酸化，及p38 MAPK、MMP-2、3、9蛋白表达; 免疫荧光法检查心肌组织FN的分布。结果: 瓣膜病所致心力衰竭病人心肌组织呈典型的心肌重构病理改变。心力衰竭组心肌 p38 MAPK 磷酸化明显强于对照组（P<0.05），随心功能恶化，其表达逐渐增加（P<0.05或P<0.01）。 心力衰竭组心肌组织MMP-2、3、9蛋白表达明显强于正常对照组，各心力衰竭组与正常对照组相比差异显著（P<0.05或P<0.01）; 相反，心力衰竭组心肌组织FN蛋白表达明显弱于正常组，各心力衰竭组与正常对照组相比差异显著（P<0.05或P<0.01）。结论: 心力衰竭病人通过激活p38 MAPK诱导心肌细胞肥大、坏死，通过MMP-2、3、9表达量的增高降解心肌细胞外基质FN，共同参与心肌重构的病理过程而恶化心功能。     

New insights into the roles of matrix metalloproteinases in colorectal cancer development and progression

This review outlines new concepts that are emerging for the functions of matrix metalloproteinases in colorectal cancer development and progression. The two main concepts that will be discussed are the role of matrix metalloproteinases in the early stages of colorectal tumour development and the functional mechanisms by which matrix metalloproteinases contribute to colorectal tumour invasion and metastasis. The matrix metalloproteinases are a group of enzymes, which have been best characterized for their ability to degrade extracellular matrix proteins and thus they have been extensively studied in tumour invasion. It is now becoming recognized that the matrix metalloproteinases have key roles in a variety of biological processes that are distinct from their well-defined role in matrix degradation. This group of enzymes has been shown to interact with a broad range of non-matrix proteins including growth factors and their receptors, mediators of apoptosis, and cell adhesion molecules. The elucidation of novel biological roles for the matrix metalloproteinases also challenges the current predominant concept of matrix metalloproteinases as enzymes only involved in matrix degradation. Recent studies have shown that several matrix metalloproteinases, especially matrilysin (MMP-7), interact with the specific molecular genetic and signalling pathways involved in colorectal cancer development. In particular, matrilysin is activated at an early stage of colorectal tumourigenesis by the beta-catenin signalling pathway. Furthermore, studies are now elucidating specific mechanisms by which individual matrix metalloproteinases, especially membrane-type matrix metalloproteinases, interact with specific cell adhesion molecules and cytoskeletal proteins and thus contribute dynamically to colorectal tumour invasion.     

Elevated angiogenin levels in synovial fluid from patients with inflammatory arthritis and secretion of angiogenin by cultured synovial fibroblasts

Angiogenesis is a key process in the pathogenesis of inflammatory arthritis. Angiogenin is one of the most potent inducers of neovascularization in experimental models in vivo. To look for evidence that angiogenin is involved in inflammatory joint disease, we examined plasma and synovial fluid (SF) samples from rheumatology patients and synovial fibroblast cell culture supernatants. Angiogenin levels were determined by radioimmunoassay and ELISA. Plasma angiogenin concentrations ranged from 96 to 478 ng/ml, with no significant difference between patients and normal controls. In SF, angiogenin concentrations were significantly higher in patients with acute or chronic synovitis (rheumatoid arthritis (RA): median, 104 ng/ml; range 13-748, n = 14; crystal-induced arthritis (CIA): median, 149 ng/ml; range, 37-616, n = 14, and other chronic inflammatory arthritis: median, 42 ng/ml; range, 15-205; n = 9) than in the 18 patients with osteoarthritis (OA) (median, 20 ng/ml; range 8-116) (P < 0.0001, anova). Angiogenin levels in SF from RA patients in remission with secondary OA were similar to those achieved in primary OA, and decreased in parallel with the resolution of acute gout. Angiogenin protein was released by cultured synovial fibroblasts from OA and RA patients, and reached 1.18 ng/106 cells/day. These data suggest that angiogenin may mediate local inflammation in arthritis via effects on angiogenesis and leucocyte regulation.     

MicroRNA-16对类风湿关节炎患者滑膜成纤维细胞增殖、侵袭及细胞因子分泌的影响

 目的:研究microRNA-16（miR-16）对类风湿关节炎（rheumatoid arthritis,RA）患者滑膜成纤维细胞（rheumatoid arthritis synovial fibroblasts,RASFs）增殖、侵袭及细胞因子分泌的影响。方法: 体外分离培养RASFs,脂质体转染化学合成的miR-16 mimic或miR-16抑制剂,分别采用MTT法、Transwell小室法和流式细胞术检测其对RASFs增殖、侵袭及凋亡的影响;RT-PCR和Western blotting检测miR-16对RASFs基质金属蛋白酶3/13（matrix metalloproteinase 3/13,MMP3/13）及白细胞介素1β（interleukin 1β,IL-1β）表达的影响。结果:增殖实验结果表明miR-16可显著抑制RASFs的增殖;细胞侵袭结果表明miR-16可显著抑制RASFs的侵袭;流式细胞术检测发现miR-16对RASFs凋亡无显著影响;miR-16可下调MMP3/13及IL-1β的表达水平。结论:  miR-16在RA的发生中起着重要作用,它可能通过下调MMP3/13及IL-1β的表达抑制RASFs增殖和侵袭。这为进一步研究miR-16在RA中的作用机制奠定了基础。     

GM-CSF对类风湿性关节炎患者单核细胞合成MMP的影响

观察GM-CSF刺激前后,类风湿性关节炎(RA)患者单核/巨噬细胞基质金属蛋白酶(MMP-2、MMP-9)合成及CD147表达的变化。从RA患者外周血及滑液分离单核细胞。RPMI1640培养液中培养,加入不同剂量的GM-CSF,用明胶酶谱法测定刺激24h、48h、72h后MMP-2、MMP-9的活性。用流式细胞术测定刺激前后细胞表面CD147表达量。GM-CSF刺激后,细胞呈多形性的巨噬细胞样改变,MMP-2,MMP-9合成增加,而且这种刺激作用与GM-CSF的剂量相关,100ng/ml时刺激作用显著高于12.5ng/ml及25ng/ml;而与作用时间无显著相关性;滑液单核细胞MMP-2、MMP-9表达水平高于外周血单核细胞。GM-CSF刺激后,单核细胞表面CD147的表达显著高于刺激前;滑液单核细胞表达量高于外周血。GM-CSF刺激后,RA患者外周血及滑液单核细胞MMP-2、MMP-9表达增加,同时伴随细胞表面CD147表达增加。     

Expression of matrix metalloproteinases and their tissue inhibitors in the serum and cerebrospinal fluid of patients with meningitis

Meningitis is associated with an imbalance between matrix metalloproteinases (MMPs) and endogenous tissue inhibitors of MMP (TIMPs). Serum and CSF were collected prospectively from all patients with meningitis between January 2008 and December 2008 to measure the concentrations of MMP/TIMP in those patients who underwent a lumbar puncture for a presumptive diagnosis of meningitis. A total of 199 patients were enrolled into the study. The concentrations of CSF MMP‐9 and TIMP‐1 were significantly higher in the meningitis group compared with the control group (p 0.032 and p <0.001, respectively). However, the CSF TIMP‐4 levels were significantly lower in the meningitis groups compared with the control groups (p <0.001). Patients with bacterial meningitis had higher CSF MMP‐9 and TIMP‐1 levels than those who had aseptic meningitis and controls. Patients with various infectious meningitis etiologies tended to have higher CSF MMP‐9 expression by gelatin zymography when compared with the controls. In conclusion, MMP/TIMP system dysregulation was found in patients with meningitis, and CSF MMP and TIMP might act as novel indicators in patients with meningitis.     

类风湿性关节炎滑膜成纤维细胞骨保护素和骨形态发生蛋白-2的表达及干预

目的 探讨甲氨蝶呤（MTX）及白细胞介素-6受体（IL-6R）抗体对类风湿关节炎（RA）滑膜成纤维细胞增殖的干预及对骨保护素（OPG）、骨形态发生蛋白-2（BMP-2）的影响.方法 获取RA患者滑膜组织,消化并传代培养成纤维细胞.CCK-8法检测IL-6R抗体、甲氨蝶呤（MTX）对RA滑膜成纤维细胞活性影响;荧光定量（qRT）-PCR检测OPG和BMP-2表达.结果 与空白组相比,MTX组、IL-6R抗体组成纤维细胞的活性受到抑制（F=29.30,34.22,P＜0.05）,MTX联合IL-6R抗体组成纤维细胞的活性显著受到抑制（F=52.04,P ＜0.01）.qRT-PCR显示与空白组相比,IL-6R抗体组、MTX联合IL-6R抗体组OPG、BMP-2的表达均上升（P＜0.05）.与MTK组相比,IL-6R抗体组OPG、BMP-2的表达增加（P＜0.05）.结论 IL-6R抗体单独或联合MTK使用均能明显抑制RA滑膜成纤维细胞的活性,与MTX相比,IL-6R抗体能升高OPG、BMP-2的表达.本研究为应用IL-6R抗体预防和治疗RA关节破坏提供实验依据.     

Participation of macrophages in glomerular sclerosis through the expression and activation of matrix metalloproteinases

In order to investigate the role of macrophages in glomeruli in the progression of glomerular sclerosis, methyl-cellulose (MC) was administered intraperitoneally to Wistar rats, in addition to intravenous injection of anti-thy1-1 antibody. In this group of rats (Thy-1 + MC group), many macrophages infiltrated in the lytic mesangium accompanied by rupture of capillary loops at an early stage and stayed with abundant deposition of mesangial matrices until day 35, whereas the proliferative lesions following mesangiolysis almost vanished in the rats treated with anti-thy1-1 antibody alone (Thy-1 group). In immunostaining, matrix metalloproteinase (MMP)-9 was expressed along regenerating capillaries of the Thy-1 group and in extracapillary lesions of the Thy-1 + MC group after day 7. In gelatin zymography, the gelatinolytic band for MMP-9 was expressed much more strongly in the Thy-1 + MC group than in the Thy-1 group at day 3, but it was expressed a little more strongly in the Thy-1 group than in the Thy-1 + MC group at day 7. The bands for an active form of MMP-2 were more strongly expressed in the Thy-1 + MC group than in the Thy-1 group throughout the experimental period. These results suggest that persistent accumulation of macrophages in mesangium induces glomerular sclerosis through expression and activation of MMP.     

白介素受体相关激酶-1基因多态性与类风湿关节炎的相关性

目的探讨白介素受体相关激酶-1(IRAK1)rs3027898和rs1059703多态性性与类风湿关节炎(RA)易感性及临床参数的关系。方法收集RA患者123例和体检的220名健康对照者外周血标本,采用聚合酶链反应-连接酶检测反应(PCR-LDR)方法检测IRAK1 rs3027898和rs1059703基因多态性,收集并计算RA患者临床参数:发病年龄、性别、RF抗体、抗CCP抗体、RA疾病活动(DAS28≥3.2)、骨破坏和用药情况。结果 RA组IRAK1 rs3027898和rs1059703的基因型频率和等位基因频率与健康对照组比较,差异无统计学意义(P>0.05)。RA患者IRAK1 rs3027898和rs1059703基因型与发病年龄、性别、RF抗体和抗CCP抗体阳性率、骨破坏阳性率均无相关性(P>0.05)。RA患者IRAK1 rs3027898基因型与RA疾病活动无相关性(P>0.05),RA患者IRAK1 rs1059703基因型与RA疾病活动存在相关性(P<0.05),携带CT+TT基因型RA患者疾病活动的风险是携带CC基因型RA患者4.243倍(P=0.023,OR=4.243,95%CI为1.223～14.715)。结论我国汉族人群中,IRAK1 rs3027898和rs1059703多态性与RA的易感性无关,但IRAK1 rs1059703多态性可能是RA患者疾病活动的一个遗传危险因素。