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1.

Aims

Melatonin possesses various pharmacological effects including neuroprotective effects against brain ischemia. Post-ischemic increases in matrix metalloproteinase-9 (MMP-9) expression and activity mainly contribute to neuronal damage by degradation of the extracellular matrix. This study was designed to examine whether melatonin has a neuroprotective effect and an influence on MMP-9 in transient global brain ischemia.

Main methods

Mice were subjected to 20 min of global brain ischemia and sacrificed 72 h later. Melatonin (30 mg/kg) was administered 30 min before and 2 h after ischemia as well as once daily until sacrifice.

Key findings

Hippocampal pyramidal cell damage after ischemia was significantly decreased by melatonin. As observed by zymography, melatonin inhibited the increase of MMP-9 activity after ischemia. In the brain sections, the increased gelatinase activity was mainly observed in the hippocampus after ischemia and melatonin also reduced gelatinase activity. The laminin and NeuN expression levels were reduced in the hippocampal CA1 and CA2 regions after ischemia, and melatonin reduced laminin degradation and neuronal loss. A TUNEL assay demonstrated that there were TUNEL-positive cells in the hippocampus and the number of TUNEL-positive cells was significantly decreased by melatonin. There was no difference in the ischemia-induced hippocampal neuronal damage between the vehicle- and melatonin-treated groups of MMP-9 knock-out mice.

Significance

These data demonstrate that melatonin suppressed the occurrence of neuronal injury, which might be partly due to its inhibitory effects on MMP-9 in addition to its anti-oxidative effects. MMP-9 may be an important key target of melatonin in neuroprotection against global ischemia.  相似文献   

2.
Despite the importance of MMP activity in the regulation of angiogenesis, relatively little is known about the role of TIMP-4, the most recently discovered endogenous MMP inhibitor, in modulating neovascularization. It has largely been assumed that all TIMPs are capable of inhibiting angiogenesis in vivo. However, it is now widely appreciated that TIMPs-1, -2, and -3 differ significantly in their ability to modulate angiogenic processes in vitro and angiogenesis in vivo. In order to study the effect of TIMP-4 in controlling angiogenesis, we have cloned and expressed TIMP-4 in a Pichia pastoris expression system, purified it to homogeneity, and tested its ability to regulate angiogenesis in vivo and in vitro. Our studies demonstrate that TIMP-4 is an inhibitor of capillary endothelial cell migration, but not of proliferation or of angiogenesis in vivo.  相似文献   

3.
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   

4.
Metalloproteinases (MMP)-2 and MMP-9 play a role in smooth muscle cell (SMC) migration from the media to the intima following arterial injury. Intravenous administration of adenovirus encoding tissue inhibitor of metalloproteinase-1 (TIMP-1) into balloon-injured rat arteries (3 x 10(11) viral particles/rat; n=7) resulted in a transient expression of TIMP-1 and a significant inhibition of neointima thickening within 16 days ( approximately 40% vs. control; P=0.012). Three days after injury, the number of intimal SMCs was decreased by approximately 98% in TIMP-1-treated rats. However, no alteration was seen in intimal SMC proliferation after 13 days of injury. Therefore, our results show that systemic gene transfer of TIMP-1 is a promising approach in early restenosis treatment.  相似文献   

5.
6.
基质金属蛋白酶及其抑制因子与扩张型心肌病的关系   总被引:2,自引:0,他引:2  
目的研究基质金属蛋白酶-2(MMP-2)及金属蛋白酶组织抑制因子(TIMP-1)在扩张型心肌病(DCM)中的变化,探讨血管紧张素转换酶抑制剂(ACEI)对心肌纤维化的影响及其调控机制。方法雄性SD大鼠腹腔注射阿霉素(2 mg/kg,每周1次,连续8周)建立扩张型心肌病模型。将达到DCM诊断标准的大鼠分3组:①H组(卡托普利高剂量干预组,50mg/Kg.d);②L组(卡托普利低剂量干预组,25mg/Kg.d);③C组(DCM对照组)。HE染色和苦味酸天狼星红染色观察各组大鼠心肌细胞和间质胶原变化,RT-PCR法检测心肌MMP-2及TIMP-1的表达。结果与正常对照组比较,DCM组心肌细胞坏死明显、胶原纤维和胶原容积分数增加(P<0.05);而H组和L组的胶原纤维较C组减少(P<0.05)。DCM组心肌MMP-2 mRNA表达较正常对照组显著增加(P<0.01),H组和L组较C组降低(P<0.05)。DCM组TIMP-1mRNA的表达较正常对照组降低(P<0.05),H组较C组有所增加(P<0.05)。结论 MMP-2及TIMP-1与心肌细胞外基质的重塑密切相关,ACEI有降解MMP-2的作用,可以减轻心肌间质的...  相似文献   

7.
The growth factor heregulin-β1 (HRG-β1), which is expressed in breast cancer, activates the HER-2 signaling pathway through induction of heterodimeric complexes of HER-2 with HER-3 or HER-4. It has been shown in many studies that HRG-β1 induces the tumorigenicity and metastasis of breast cancer cells. Matrix metalloproteinase (MMP) 9 is a key enzyme in the degradation of extracellular matrices, and its expression may be dysregulated in breast cancer invasion and metastasis. Resveratrol, a major component in grape, exhibited potential anticarcinogenic activities in both in vitro and in vivo studies. However, the inhibitory effect of resveratrol on HER-2-mediated expression of MMP-9 has not been demonstrated yet.

In the present study, we investigated the anti-invasive mechanism of resveratrol in human breast cancer cells. Human breast cancer MCF-7 cells were exposed to resveratrol (2, 5 and 10 μM). The expression activity of MMP-9 was measured by zymogram analysis. Phosphorylated levels of HER-2 and mitogen-activated protein kinase (MAPK)/ERK were measured by Western blot analysis. Total actin was used as internal control for protein expression. HRG-β1 induced the phosphorylation of HER-2/neu receptor and MMP-9 expression in human breast cancer MCF-7 cells. Resveratrol significantly inhibited HRG-β1-mediated MMP-9 expression in human breast cancer cells. MEK inhibitor induced a marked reduction in MMP-9 expression, and it suggested that ERK1/2 cascade could play an important role in HRG-β1-mediated MMP-9 expression. Furthermore, resveratrol significantly suppressed HRG-β1-mediated phosphorylation of ERK1/2 and invasion of breast cancer cells. However, resveratrol had negligible effects on either HRG-β1-mediated phosphorylation of HER-2 receptor or expression of the tissue inhibitor of MMP, tissue inhibitor metalloproteinase protein 1.

Taken together, our results suggest that resveratrol inhibited MMP-9 expression in human breast cancer cells. The inhibitory effects of resveratrol on MMP-9 expression and invasion of breast cancer cells are, in part, associated with the down-regulation of the MAPK/ERK signaling pathway.  相似文献   


8.
Matrix metalloproteinases (MMPs) are a family of zinc-dependent enzymes capable of degradation of extracellular matrix (ECM) and key player in various inflammatory diseases. We investigated the regulation of MMPs in chronic gastric ulceration in mice. We generated chronic gastric ulcers in mice by indomethacin and examined the activity and expression of MMP-9 and -3 in stomach. Melatonin (N-acetyl-5-methoxytryptamine) treatment has also been applied to mice to characterize the changes in expression and activities of MMPs in gastric tissues. We observed significant upregulation of MMP-9 and -3 expressions and activities in stomach with increasing doses and duration of indomethacin that corroborated with increased activity of activator protein (AP)-1. Substantial damage in gastric epithelial layer was found during chronic ulceration. Melatonin suppressed MMP-9 and -3 expressions and activities during prevention and healing of chronic gastric ulcers. It also suppressed protein oxidation, lipid peroxidation and antioxidant enzymes. Additionally, expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-8 was significantly high in ulcerated stomachs while melatonin treatment blocked them to control level. We found elevated phosphorylation of extracellular-regulated kinase (ERK)1/2 and c-Jun N-terminal kinase (JNK) during chronic gastric ulceration, which were significantly reversed by melatonin. Moreover, expression of NF-κB, c-fos and c-jun were inhibited by melatonin resulting down regulation of MMP-9 and -3 expressions. In summary, oxidative stress is preceded by chronic inflammation that enhances the expression of MMP-9 and -3, while melatonin arrests both of them via reduction of AP-1 activity during protection of ulcer.  相似文献   

9.
Several lines of evidence speak for an important role of matrix metalloproteinases (MMPs) in the development of progressive joint destruction. To better understand the role of MMPs and their tissue inhibitors (TIMPs) in this process, we have used the antigen-induced arthritis model to study the temporospatial expression of several MMPs and TIMPs during the progression of arthritis. Arthritis was induced by a single intra-articular injection of methylated bovine serum albumin (mBSA) into one or both knee joints of adult mice previously immunised against mBSA. Samples were collected at 3, 7, 21 and 42 days after induction of arthritis for histology and RNA extraction, and analysed by Northern hybridisation, histochemistry and immunohistochemistry for production of several MMPs and TIMPs −1, −2 and −3. A systematic analysis of MMP and TIMP mRNA levels in mouse knee joints demonstrated a general upregulation of both MMPs and TIMPs during progression of arthritis. Upregulation of MMP-9, −13 and −14 coincided with the advancement of cartilage degeneration, but the expression patterns of MMP-9 and −13 also followed the course of synovial inflammation. TIMPs were steadily upregulated throughout the examination period. Immunohistochemical localisation of MMPs and TIMPs suggested the synovium to be the major source of MMP and TIMP production in arthritis, although articular cartilage chondrocytes also showed an increased production of both MMPs and TIMPs.  相似文献   

10.
We have previously shown that matrix metalloproteinase-9 (MMP-9) activity is greatly enhanced within the active chronic inflammation of Helicobacter pylori infected individuals, of which a major fraction derives from macrophages in the tissue. Here, we have investigated the ability of macrophages to secrete MMPs in response to H. pylori. Human macrophages secrete MMP-9 in response to live and inactivated H. pylori, as well as to specific bacterial products. Protein kinase C, phosphatiolylinositol 3-kinase and calcium uptake channels all play a role in MMP-9 secretion, whereas neither tumour necrosis factor alpha, interleukin-8, nor interleukin-1beta autocrine stimulation appear to contribute. We conclude that human macrophages have the ability to react directly against several H. pylori derived factors, utilising several signalling pathways.  相似文献   

11.
肺泡 毛细血管基底膜损伤是体外循环 (CPB)术后肺损伤发生和发展的主要病理过程 ,基质金属蛋白酶 (MMPs)可能通过降解细胞外基质、调节细胞因子而参与CPB所致肺损伤的发生 ,研究MMPs在CPB肺损伤中的作用机制 ,对于防治CPB术后肺损伤的发生和发展具有重要意义  相似文献   

12.
目的研究基质金属蛋白酶(MMPs)-2、-9及组织型基质金属蛋白酶抑制剂(TIMPs)-1在大鼠肺组织中的增龄性变化规律。方法不同月龄(1月龄、3月龄、12月龄、18月龄、24月龄)雄性清洁级(SD)大鼠47只分为5组,按月龄取实验大鼠的右下叶肺组织,用流式细胞术检测MMP-2、MMP-9及TIMP-1的表达水平,进行定量分析。结果 MMP-2、MMP-9和TIMP-1均随着月龄的增长呈先降后升波谷型曲线变化;3月龄、12月龄和18月龄MMP-2、MMP-9和TIMP-1均较1月龄明显下降,且以12月龄为最低值;24月龄MMP-2、MMP-9和TIMP-1均较1月龄上升。MMP-2/TIMP-1比值和MMP-9/TIMP-1比值均随着月龄的增长呈先升后降波峰型曲线变化;12月龄和18月龄均较1月龄明显升高,且以18月龄为最高点;3月龄的MMP-2/TIMP-1较1月龄有所上升,3月龄的MMP-9/TIMP-1与1月龄持平;24月龄的MMP-2/TIMP-1和MMP-9/TIMP-1较1月龄也有不同程度上升。结论大鼠肺组织中MMPs及其抑制剂TIMPs随月龄的增长,呈特征性变化规律。  相似文献   

13.
《Phytomedicine》2014,21(10):1137-1145
Aortic aneurysm (AA) is a life-threatening vascular disease in defect of effective pharmaceutical therapy. Matrix metalloproteinase-9 (MMP-9) is implicated in the development of chronic vascular diseases including aneurysm, but the effective MMP-9 inhibitors are far from development. To develop new candidate for AA therapy, we evaluated the efficiency of salvianolic acid A (SalA), a novel MMP-9 inhibitor, on AA progression in a mouse model and characterized the mechanism of action. SalA is a water soluble compound of the herbal drug Rhizoma Salviae miltiorrhizae (Danshen) which in China is widely used for the treatment of hypertension, coronary artery diseases and myocardial infarction. MMPs activity was evaluated by enzyme kinetic analysis in vitro and in-gel gelatin zymography in vivo. SalA showed selectivity on gelatinase (MMP-2 and MMP-9) than on collagenase (MMP-8 and MMP-13) in vitro, and specificity on MMP-9 than MMP-2 in vivo. Aortic aneurysm was induced by angiotension II (AngII) in apolipoprotein E-deficient (ApoE−/−) mice. Aortic structure was evaluated by hematoxylin and eosin, picrosirius red, orein stain. Macrophage infiltration was detected by immunohistochemistry in vivo and transwell in vitro. Comparing with doxycycline (Dox), a well-known MMPs inhibitor, SalA showed similar efficiency against AA progression. SalA significantly decreased aortic diameter and aneurysm severity, ameliorated integrity of vascular structure, inhibited elastin fragmentation and macrophage infiltration. Furthermore, SalA showed greater safety than Dox based on hepatotoxicity evaluation. Our results demonstrated that SalA held great potential for AA therapy.  相似文献   

14.
15.
Interleukin (IL)-17, a proinflammatory cytokine, is produced primarily by activated Th17 cells. IL-17 consists of six ligands that signal through five receptors (IL-17Rs); IL-17A and IL-17F share the highest homology in the family. Matrix metalloproteinases (MMPs) degrade the extracellular matrix during cartilage remodeling whereas tissue inhibitor of metalloproteinases (TIMPs) inhibit the action of MMPs. In the present study, we examined the effect of IL-17F on the degradation and synthesis of the extracellular matrix in cartilage using human articular chondrocytes. We examined the effect of IL-17F on the expression of IL-17Rs, MMPs, TIMPs, type II collagen, aggrecan, link protein, and cyclooxygenases (COXs), as well as on prostaglandin E2 (PGE2) production. We also examined the indirect effect of PGE2 on the above IL-17F-induced/reduced components using NS-398, a specific inhibitor of COX-2. Cells were cultured with or without IL-17F in the presence or absence of either an IL-17R antibody or NS-398 for up to 28 days. Expression of IL-17Rs, MMPs, TIMPs, type II collagen, aggrecan, link protein, and COXs at mRNA and protein levels was determined using real-time polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA), respectively. PGE2 production was determined by ELISA. The expression of all types of IL-17Rs was detected in chondrocytes. However, IL-17RE expression was extremely low, compared with other IL-17Rs. The expression of MMP-1, MMP-3, MMP-13, and COX-2 as well as PGE2 production were increased by addition of IL-17F, whereas the expression of IL-17RD, TIMP-2, TIMP-4, type II collagen, aggrecan, link protein, and COX-1 was decreased. The expression of IL-17RA, IL-17RB, IL-17RC, MMP-2, MMP-14, TIMP-1, and TIMP-3 was unaffected by addition of IL-17F. The IL-17R antibody blocked the stimulating/reducing effect of IL-17F on the expression of MMP-1, MMP-3, MMP-13, TIMP-2, TIMP-4, type II collagen, aggrecan, and link protein. NS-398 blocked the reducing effect of IL-17F on aggrecan expression, whereas it did not completely block the stimulating/reducing effects of IL-17F on the expression of MMP-1, MMP-3, MMP-13, TIMP-2, TIMP-4, type II collagen, and link protein. Our results suggest that IL-17F stimulates cartilage degradation by increasing the expression of collagenases (MMP-1 and -13) and stromelysin-1 (MMP-3) and by decreasing expression of their inhibitors (TIMP-2 and -4), type II collagen, aggrecan, and link protein in chondrocytes. Furthermore, our results suggest that the expression of aggrecan, link protein, and TIMP-4 decrease through the autocrine action of PGE2 in chondrocytes.  相似文献   

16.
Liu CH  Wu PS 《Biotechnology letters》2006,28(21):1725-1730
There is little information available on the proteases expressed by human embryonic kidney (HEK) cells, which are often used for expression of recombinant proteins and production of adenovirus vector. The expression profile of proteases in HEK cell line was investigated using zymography, mRNA analysis, western blotting and protein array. The major protease was gelatinase A [or matrix metalloproteinase (MMP)-2]. Beside, other MMPs, such as MMP-1, -2, -3, -8, -9, -10, -13 and membrane type (MT) 1- and 3−MMP, as well as tissue inhibitors of metalloproteinase (TIMP)-1, -2 and -3, were also expressed by HEK cells. Characterization of MMP and TIMP profiles expressed by HEK cells provides the basis for degradation control of recombinant protein and adenovirus vector during culture and purification processes.  相似文献   

17.
Elevated expression of matrix metalloproteinases (MMPs), especially that of MMP-2 and MMP-9, is associated with increased metastatic potential in many tumor cells. Recently, green tea polyphenol epigallocatechin-3-O-gallate (EGCG) has been shown to inhibit the MMP-2/-9 activity as well as the invasiveness of tumor cells. In this study, we have examined the inhibitory effect of hydrolyzable tannins (plant polyphenols) on the tumor cell invasion. Our results demonstrate that beta-d-glucose whose hydroxy groups are substituted entirely with galloyl group and further some of them are cross-linked to form hexahydroxydiphenoyl group, for example, suppresses the invasiveness of tumor cells much more potently than EGCG via direct inhibition of the MMP-2/-9 activity. Among those examined, 1,2,4-tri-O-galloyl-3,6-hexahydroxydiphenoyl-beta-d-glucose (punicafolin) inhibits the invasion of HT1080 fibrosarcoma cells most potently. These hydrolyzable tannins would provide new leads for the development of potent inhibitors against tumor metastasis.  相似文献   

18.
Matrix metalloproteases (MMPs) are endogenous proteases that are responsible for degradation of extracellular matrix (ECM) proteins and cell surface antigens. The breakdown of ECM participates in the local invasion and distant metastases of malignant tumors. Canine transmissible venereal tumor (CTVT) is a naturally occurring contagious round cell neoplasm of dogs that affects mainly the external genitalia of both sexes. CTVT generally is a locally invasive tumor, but distant metastases also are common in puppies and immunocompromised dogs. We investigated the immune expressions and activities of MMP-2 and MMP-9 in CTVT. The presence of these enzymes in tumor cells and tissue homogenates was demonstrated by immunohistochemistry and western blotting. We used gelatin substrate zymography to evaluate the activities of MMP-2 and MMP-9 enzymes in tumor homogenates. We found that tumor cells expressed both MMP-2 and MMP-9. Electrophoretic bands corresponding to MMP-9 and MMP-2 were identified in immunoblots and clear bands that corresponded to the active forms of MMP-2 and MMP-9 also were detected in gelatin zymograms. Our study is the first detailed documentation of MMPs in CTVT.  相似文献   

19.
目的:研究基质金属蛋白酶2(Matrix Metalloproteinase-2,MMP-2),基质金属蛋白酶7(MMP-7),基质金属蛋白酶9(MMP-9),膜型基质金属蛋白酶(Membrane Type-1 Matrix Metalloproteinase,MT1-MMP),金属蛋白酶组织抑制剂1(Tissue Inhibitor of Metalloproteinase,TIMP-1),金属蛋白酶组织抑制剂2(TIMP-2)在乳腺癌组织中mRNA的表达,及与临床病理变量之间的关联。方法:采用150例乳腺癌患者的组织样本。使用半定量逆转录-聚合酶链反应(RT-PCR)法来测定肿瘤组织和正常乳腺组织中MMP-2,MMP-7,MMP-9,MT1-MMP,TIMP-1和TIMP-2的mRNA表达。结果:MMP-2,MMP-7,MMP-9,MT1-MMP,TIMP-1和TIMP-2在乳腺癌中的mRNA表达显著高于正常组织。结论:MMP-2,MMP-7,MMP-9,和MTI-MMP的表达增加和临床病理参数之间的关联,可以用来预测乳腺癌的侵害行为。  相似文献   

20.
目的:基质金属蛋白酶及组织金属蛋白酶抑制剂在肾细胞癌转移中占有重要的作用,研究肾细胞癌组织中MMP-2、MMP-9、TIMP-1和TIMP-2的表达情况,为肾癌转移的治疗提供理论依据。方法:选取36例肾细胞癌肾组织标本,从相同的肾细胞癌组织及癌旁肾组织获得对照样本,均进行根治性肾切除手术切除。肿瘤分期按TNM分期标准。为了统计评估,肿瘤1期和2期为低级,3期以上为高级。RT-PCR检测肿瘤和正常组织中的MMP-2、MMP-9、TIMP-1和TIMP-2的表达。结果:不同样本MMPs和TIMPs表达水平各不相同。肾细胞癌组织中MMP-2、MMP-9、TIMP-1、TIMP-2在肾细胞癌中的表达明显高于正常肾组织(P0.05)。在肾细胞癌的肿瘤分期方面,MMP-2与MMP-9和肿瘤的分期显著相关,随着肿瘤分期的增加,MMP-2与MMP-9的表达明显升高(P0.05),而TIMP-1与TIMP-2与肿瘤的分期无关。结论:肾细胞癌组织中TIMP-2、MMP-2,MMP-9,TIMP-1的mRNA表达显著高于正常肾组织,抑制MMPS的表达将成为治疗肾细胞癌转移的新的方向。  相似文献   

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