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1.
B G Schoser  D Blottner 《Neuroreport》1999,10(13):2795-2797
Proteolytic enzyme expression was studied by matrix metalloproteinases (MMP) immunoreactivity (-IR) in muscle biopsies from patients with amyotrophic lateral sclerosis (ALS), spinal muscle atrophy (SMA) and chronic axonal neuropathies (CANP). In normal muscle MMP-2-, MMP-7-, and MMP-9-IR was localized at neuromuscular junctions, in vessels and nerve branches. ALS biopsies of clinically non-affected muscles revealed neither MMP-2, -7-IR nor MMP-9-IR in atrophied myofibers. ALS-affected biopsies revealed MMP-9-IR, and to lesser extent MMP-2- and MMP-7-IR at normal sized and atrophied myofibers. Biopsies of SMA showed MMP-9- and MMP-7-IR at normal sized and atrophic myofibers, while MMP-2-IR was undetectable. In CANP MMP-9-IR was found at normal sized and atrophied myofibers. Distinct expression patterns of MMPs may thus reflect different stages of muscle denervation atrophy.  相似文献   

2.
OBJECTIVES: The aim of our study was to investigate immunoexpression of matrix metalloproteinases MMP2, MMP7 and MMP9 in muscle specimens from patients with focal myositis (FM) vs polymyositis (PM) and dermatomyositis. MATERIALS AND METHODS: We studied muscle biopsy samples from seven patients affected by FM; samples from five patients each with PM and dermatomyositis were studied as disease controls. RESULTS: MMP2 immunoreactivity was present in PM and dermatomyositis, MMP7 only in PM, and MMP9 in PM, dermatomyositis and FM. CONCLUSIONS: Our results confirm that increased MMP9 immunoreactivity in muscle fibres is a common feature of all inflammatory myopathies and suggest that MMP2 and MMP7 cannot be implicated in the inflammatory events of FM.  相似文献   

3.
In a nerve crush model of denervation, we examined muscle matrix metalloproteinase (MMP) expression, localization and activity. In normal muscle, MMP mRNA levels were low, and immunohistochemically MMPs were distributed around the muscle fibre with MMPs-3, -7 and -9 also staining at the neuromuscular junction. Seven days after nerve crush, muscle MMP immunoreactivity, especially MMP-12 and MMP-14, became irregularly distributed. At 20 days reinnervation of the muscle was observed, and some restitution of the normal pattern of immunoreactivity was noted concomitant with a higher level of MMP mRNA expression. In situ zymography showed that MMP activity was very weak in normal muscle whereas it was increased up to 40 days following denervation. Our results suggest that MMPs in muscle are involved in the tissue changes following denervation. Further experiments are required to test the hypothesis that MMP inhibition may be beneficial in protecting muscle from excessive remodelling following denervation and therefore improve reinnervation.  相似文献   

4.
We monitored serum levels of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) before and during intravenously applied immunoglobulin (IVIG) therapy in 33 patients with chronic immune-mediated neuropathies and myopathies and 15 controls. Baseline MMP-2 and TIMP-2 serum levels were lower and MMP-9 and TIMP-1 serum levels higher in all patients compared to age-matched controls. Eight days after IVIG treatment, MMP-2, TIMP-2, and TIMP-1 serum levels increased, while MMP-9 serum levels decreased, indicating tissue repair. After 60 days, MMP-9 levels increased, MMP-2 approached normal levels, while TIMP-1 and TIMP-2 serum levels were below day 8 levels, indicating relapsing tissue damage. Comparing the MMP/TIMP results with the clinical courses, IVIG treatment tended to change MMP/TIMP levels in a way that paralleled clinical improvement and relapse. In sum, during a distinct time period, IVIG therapy seems to be able to modulate MMP-mediated tissue repair.  相似文献   

5.
Matrix metalloproteinase (MMP) activity is implicated in the degradation of the extracellular matrix during cerebral ischemia. Although many studies have demonstrated spatiotemporal patterns of activation of gelatinases (MMP-9 and MMP-2) after ischemic stroke in young adult rodents, no data exist on MMP activity in old brains. In this study, we investigated the gelatinolytic activity in young adult (3-month-old) and aged (1-year-old) mice subjected to photothrombotic stroke. Using in situ zymography and gel zymography, we found that the basal gelatinolytic activity in the intact cerebral cortex was similar at both investigated ages. Similarly, after photothrombosis, the increased gelatinolytic response up to 7 days poststroke was the same in young and aged brains. At both ages, early activation of gelatinolysis in the ischemic core and the perilesional area was present in neuronal nuclei as revealed by colocalization of gelatinolytic product with NeuN immunostaining and DAPI. Additionally, application of specific antibodies against MMP-9 and MMP-2 revealed the increase in MMP-9 immunoreactivity in cell nuclei as early as 4 hr poststroke. No differences between young and aged mice were observed concerning the level and localization of MMP-9 immunoreactivity. The lack of age-related differences in the degree and pattern of activation of gelatinolysis after focal stroke and the lack of correspondence between the results of in situ and gel zymography suggest that extracellular proteolysis is not directly responsible for the more severe outcome of ischemic stroke in aged subjects.  相似文献   

6.
Matrix metalloproteinases (MMPs) are endoproteases that have been implicated in the pathogenesis of inflammatory and vasculitic neuropathies. In systemic lupus erythematosus (SLE), a peripheral neuropathy is frequently seen that is thought to be caused by ischemic nerve damage due to vasculopathy and/or vasculitis of the nutritional vessels. However, the exact pathomechanisms causing SLE neuropathy are largely unknown. Elevated MMP levels have been reported in the serum of SLE patients. Supposing that altered expression of MMPs may contribute to vessel wall damage in SLE neuropathy, we investigated the expression of MMP-1, -2, -3, -9, -10 and -13, and their tissue inhibitors (TIMP-1 and -2) in sural nerves from 12 SLE patients in comparison to normal controls. All MMPs could be detected within blood vessel walls from SLE nerves, whereas in controls MMP-3 and MMP-9 was not found. TIMP-1 and TIMP-2, on the other hand, were not informative. Generally, small and large nutritional vessels in the epineurium were immunoreactive for MMPs and TIMPs. Mononuclear cells, which expressed MMP-1, - 3, -10, -13, and TIMP-1 were also observed in most of the SLE nerves, mostly around epineurial blood vessels, but only occasionally in controls. This indicates that expression of MMPs in mononuclear cells may be related to leukocyte trafficking through the vessel walls. However, the density of TIMP-positive and MMP-positive inflammatory cells did not correlate with morphometric parameters regarding the severity of the neuropathy. Our findings suggest that especially the up-regulation of MMP-3 and MMP-9 within the vessel walls may be responsible for the vascular damage seen in SLE and the resulting chronic combined axonal and demyelinating type of neuropathy frequently found in SLE.  相似文献   

7.
Choi YC  Dalakas MC 《Neurology》2000,54(1):65-71
OBJECTIVE: To investigate the role of matrix metalloproteinases (MMPs) in the pathogenesis of inflammatory myopathies and the amyloid formation in sporadic inclusion body myositis (s-IBM). BACKGROUND: MMPs comprise a family of calcium-dependent zinc endoproteinases induced by cytokines and secreted by inflammatory cells. They enhance T-cell migration or adhesion and degrade components of the extracellular matrix proteins. Some MMPs also have been implicated in the formation of beta-amyloid. METHODS: We examined the expression of MMPs with single and double immunocytochemistry using antibodies against MMP-2, MMP-3, MMP-7, MMP-9, major histocompatibility complex (MHC) class I, CD8+ cells, macrophage, and beta-amyloid precursor protein (beta-APP) on serial muscle biopsy sections from patients with s-IBM, polymyositis (PM), dermatomyositis (DM), and disease control specimens. The enzyme activity of MMPs was measured by gelatin substrate zymography. RESULTS: Only the gelatinases, MMP-9 and MMP-2, were expressed in the muscle. In s-IBM and PM, but not the control specimens, MMP-9 and MMP-2 immunostained the non-necrotic and MHC class-I-expressing muscle fibers, and MMP-9, but not MMP-2, immunostained the autoinvasive CD8+ cytotoxic T cells. Zymography in muscle homogenates confirmed the increased MMP-2 and MMP-9 enzymatic activity. MMP-2, but not MMP-9, immunostained the rimmed vacuoles in s-IBM and colocalized with beta-APP, suggesting a possible involvement with the amyloid deposits. CONCLUSIONS: Because collagen IV is prominent on the muscle membrane, the overexpression of matrix metalloproteinases (MMPs) 2 and 9 on the non-necrotic muscle fibers in polymyositis (PM) and sporadic inclusion body myositis (s-IBM) may facilitate lymphocyte adhesion and enhance T-cell-mediated cytotoxicity by degrading extracellular matrix proteins. The findings may have practical implications in considering therapeutic trials with MMP inhibitors in patients with PM and s-IBM.  相似文献   

8.
Matrix metalloproteinases (MMPs) are a family of enzymes that may be implicated in the pathogenesis of inflammatory demyelinating disorders such as multiple sclerosis. The present study investigated the expression of 92-kd gelatinase (MMP-9) and five other MMPs in sciatic nerve from Lewis rats with autoimmune experimental neuritis (EAN), an experimental model of the Guillain-Barre syndrome(GBS). Quantitative polymerase chain reaction analysis revealed an up-regulation of MMP-9 mRNA with peak levels concurrent with maximal disease severity. Increased mRNA expression was associated with enhaced enzyme activity, as detected by gelatin zymography. Immunohistochemically, MMP-9 could be localized primarily around blood vessels within the epineurium and enhoneurium in diseased but not normal sciatic nerve. Among all other MMPs investigated, mRNA levels of matrilysin (MMP-7) were found to be up-regulated at the peak of the disorder, remaining at high levels throughout the clinical recovery phase of the disease. To apply these findings to human disease, sural nerve biopsies from GBS patients were examined. By using immunohistochemistry, positive immunoreactivity against MMP-9 and MMP-7 was noted and corroborated by demonstrating augmented mRNA expression in comparison with noninflammatory neuropathies. Furthermore, increased MMP-9 activity was detected by zymography. These findings indicate that 92-kd gelatinase and matrilysin are selectively up-regulated during EAN and expressed in nerves of GBS patients and thus may contribute to the pathogenesis of inflammatory demyelination of the peripheral nervous system.  相似文献   

9.
The pathology of multiple sclerosis (MS) is characterised by breakdown of the blood-brain barrier accompanied by infiltration of macrophages and T cells into the central nervous system (CNS). Myelin is degraded and engulfed by the macrophages, producing lesions of demyelination. Some or all of these mechanisms might involve proteinases, and here we have studied the cellular localisation and distribution of two matrix metalloproteinases (MMPs), MMP-7 (matrilysin) and MMP-9 (92-kDa gelatinase), in the normal human CNS and active demyelinating MS lesions. Cryostat sections of CNS samples were immunostained with antisera to MMP-7 and MMP-9. In addition, non-radioactive in situ hybridisation (ISH) was performed using a digoxygenin-labelled riboprobe to detect the expression of MMP-7. MMP-7 immunoreactivity was weakly detected in microglial-like cells in normal brain tissue sections, and was very strong in parenchymal macrophages in active demyelinating MS lesions. This pattern of expression was confirmed using ISH. MMP-7 immunoreactivity was not detected in macrophages in spleen or tonsil, indicating that it is specifically induced in infiltrating macrophages in active demyelinating MS lesions. MMP-9 immunoreactivity was detected in a few small blood vessels in normal brain tissue sections, whereas many blood vessels stained positive in CNS tissue sections of active demyelinating MS lesions. The up-regulation of MMPs in MS may contribute to the pathology of the disease. Received: 19 December 1996 / Revised: 22 May 1997 / Accepted: 4 June 1997  相似文献   

10.
OBJECTIVE: To determine the expression pattern and cellular source of matrix metalloproteinases (MMPs) in chronic inflammatory demyelinating polyneuropathy (CIDP) and nonsystemic vasculitic neuropathy (NSVN). BACKGROUND: MMPs are endopeptidases involved in tissue destruction and infiltration by immune cells in multiple sclerosis and Guillain-Barré syndrome. Enzyme inhibitors of MMPs attenuate clinical symptoms in corresponding animal models of these diseases. MMP inhibition may therefore be a novel approach for the treatment of CIDP and NSVN. However, the spectrum of MMPs expressed in chronic inflammatory neuropathies has not been established. METHODS: The expression of MMP-2, MMP-3, MMP-7, and MMP-9 in T cells, macrophages, and stromal cells in CIDP, NSVN, and noninflammatory neuropathies (NIN) was quantitated by immunohistochemistry. Results were correlated with clinical and electrophysiologic findings. RESULTS: The production of MMP-2 and MMP-9 is increased in nerve tissue in CIDP and NSVN compared with NIN. T cells are the predominant source of MMP-2 and MMP-9 in CIDP and NSVN, whereas macrophages contribute only to a minor extent. Stromal cells of the perineurium/epineurium are an additional source of MMP-2 in NSVN, but not in CIDP. Expression of MMP-3 and MMP-7 was not detectable in CIDP or NSVN. Expression of MMP-2 and MMP-9 did not correlate with clinical disease activity and electrophysiologic measurements. CONCLUSIONS: The upregulation of MMP-2 and MMP-9 is a specific feature of CIDP and NSVN, and selective inhibitors of these enzymes could be used to prevent inflammatory tissue damage. The similar increase of MMP-2 and MMP-9 in both demyelinating (CIDP) and nondemyelinating (NSVN) neuropathies raises doubts about whether MMPs play a primary role in demyelination.  相似文献   

11.
目的研究大鼠局灶性脑缺血后应用尿激酶(urokinase,UK)溶栓对基质金属蛋白酶-9(Matrix metalloproteinase-9,MMP-9)表达的影响,探讨MMP-9在UK溶栓引起的再灌注损伤及出血性转化中的作用。方法将实验动物随机分成3组进行研究(1)UK溶栓组;(2)缺血对照组;(3)假手术组。分别用免疫组织化学方法分析3组缺血后24hMMP-9的表达,对比研究两组MMP-9表达的差异性。结果缺血后24h前两组均有MMP-9的表达,但是UK溶栓组表达的程度明显高于缺血对照组;假手术组无MMP-9的表达。结论(1)缺血能导致MMP- 9的表达。(2)UK溶栓引起MMP-9表达的上调。  相似文献   

12.
The aim of the study was to assess the differential intra- and intertumoral heterogeneity and patterns of matrix metalloproteinase expression in human glioblastomas in vivo. 12 glioblastoma samples were analyzed for MMP expression by semi-quantitative RT-PCR. A total of 56 samples (8 adjoining regions of 6 glioblastoma tumors) were immunohistochemically examined for the expression and regional distribution of gelatinase-A (MMP-2), gelatinase-B (MMP-9), matrilysin (MMP-7) and stromelysin-1 (MMP-3). Gelatinase-A mRNA was detected in all samples, gelatinase-B was found in numerous samples. Correspondingly, strong expression levels of both gelatinase protein was seen in immunohistochemistry. Gelatinase-A was expressed by both tumor cells and endothelium while gelatinase-B was found to be restricted to endothelial cells. Stromelysin-1 protein was not detected in any of the samples. Matrilysin was found around tumor cells of three samples from one patient only. The strong immunoreactivity seen for gelatinase-A around tumor cells and blood vessels suggests a role in both tissue degradation and tumor neoangiogenesis which is in accordance with previously published in vitro data. The marked localization of gelatinase-B to the endothelium and its presence in non-infiltrative benign lesions, however, makes a direct proteolytic role of gelatinase-B on ECM components during glioma invasion appear unlikely. Its close association with vascular structures, however, might indicate a link to neoangiogenesis. The significance of matrilysin which was only seen in tumor cells in three samples remains unclear. Stromelysin-1, though strongly expressed in cell lines, does not appear to play a role in glioblastoma tumors in vivo.  相似文献   

13.
Laminin is a basement membrane (BM) glycoprotein composed of three of five subunits, the A, M, B1, B2, and the S chain. Four forms of laminin, A-B1-B2, A-S-B2, M-B1-B2, and M-S-B2, have been identified. Laminin is implicated in various biological processes such as cell adhesion and differentiation. We studied immunohistochemically the expression of the four laminin subunits A, M, B1, B2 as well as of neural cell adhesion molecule (N-CAM, CD56), a marker of regenerating myofibers, in various neuromuscular disorders. In normal muscle, the predominant subunits of myofiber laminin were M, B1, and B2. The A chain was only faintly expressed in myofiber BM. In inflammatory myopathies and dystrophinopathies myofiber laminin A expression was greatly increased. An average of 80% and 63% of laminin A–positive myofibers in inflammatory myopathies and dystrophinopathies, respectively, were additionally CD56 positive. Laminin A and CD56 expression in denervating diseases and mitochondrial myopathies were negligible. Expression of M, B1, and B2 subunits did not seem to be altered in the diseased conditions examined above. The data suggest that laminin A is upregulated in inflammatory myopathies and dystrophinopathies and, most markedly in regenerating myofibers. © 1995 John Wiley & Sons, Inc.  相似文献   

14.
Matrix metalloproteases (MMPs) are key regulatory molecules in the formation, remodeling, and degradation of extracellular matrix components in both physiological and pathological processes. Skeletal muscles of mdx dystrophic mice show distinct patterns of inflammation and regeneration, suggesting that factors within the microenvironment influence the adaptive responses of muscles with predominantly slow-twitch or fast-twitch fibers. This study aimed to verify the pattern of MMP activity in gastrocnemius, soleus, and diaphragm muscles and correlate it with the regenerative capability at distinct stages of the mdx myopathy. Marked inflammation and myonecrosis was associated with increased MMP-9 activity and TNF-alpha (tumor necrosis factor-alpha) production, whereas muscle regeneration, evidenced by NCAM (neural cell adhesion molecule) expression and MMP-2 activity, varied at different stages of the disease. Soleus muscles showed a high percentage of NCAM-positive myofibers in the early stages (2 weeks) of the disease, but they appeared in the gastrocnemius muscles at 12 weeks and in the diaphragm at 24 weeks. Increased MMP-2 activity in the diaphragm throughout all stages of the disease suggests important tissue remodeling, which is probably associated with persistent inflammation. The results indicate that the microenvironment of distinct skeletal muscle may influence a particular kinetic pattern of MMP activity, which ultimately favors persistent inflammation and myofiber regeneration at different stages of the myopathy in mdx mice.  相似文献   

15.
Aberrant expression of class I major histocompatibility complex (MHC) occurs on myofibers in inflammatory myopathies. The mechanisms responsible for such expression are unknown. Here we show that class I MHC expression is developmentally regulated during muscle regeneration with significant levels only in myoblasts. Injection of gamma-IFN plasmid leads to muscle inflammation, induction of class I MHC in regenerating, but not mature myofibers, and attenuation of regeneration. Gene transfer of class I MHC in vivo and in vitro also attenuates muscle differentiation. Thus, cytokines may contribute to the pathogenesis of inflammatory myopathies by upregulating class I MHC and leading to deleterious effects on muscle repair.  相似文献   

16.
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.  相似文献   

17.
MMP-9和MMP-2在多病程大鼠EAE发病过程中的变化   总被引:1,自引:0,他引:1  
目的:研究MMP-2和MMP-9在多病程EAE不同类型间的变化,探讨MMPs在MS发病过程中的作用机制。方法:建立多病程大鼠EAE模型,以免疫组化的方法检测MMP-2、MMP-9在不同类型EAE中的表达及分布。结果:MMP-2、-9在EAE中的表达是一致的,不同类型EAE表达MMP-2、-9是不同的。1急性型EAE:炎细胞、血管内皮细胞及细胞外基质、脑膜细胞均呈阳性表达。2缓解-复发型EAE:活动性病灶呈阳性表达,非活动性病灶呈阴性表达。3持续进展型EAE:与缓解复发型EAE表达类似,但呈阳性表达的血管内皮细胞数目多于缓解-复发型。4良性型EAE:只有部分胶质细胞呈阳性表达。5隐匿型EAE-多数病灶呈轻度表达。结论:1 MMP-2、MMP-9在EAE中均有表达。2不同类型EAE中MMP-2、MMP-9的表达是不同的,与病理改变和疾病进展是一致和同步的。  相似文献   

18.
19.
OBJECTIVE: Matrix metalloproteinases (MMPs) contribute to inflammatory and degenerative processes in injured nerves. Since mast cells release mediators which upregulate and activate MMPs, we tested the hypothesis that activation of mast cells is responsible for changes in the expression and activity of MMP-2 and MMP-9 in the injured peripheral nerve. METHODS: The sciatic nerve was partially ligated in Wistar rats in which mast cells were stabilized with sodium cromoglycate. Expression and activity of MMP-2 and MMP-9 were measured in the injured and contralateral nerve using gelatin zymography, and compared between mast cell-stabilized and control groups. RESULTS: Expression and activity of MMP-9 were increased in both the injured and contralateral nerve, but activity of MMP2 was slightly reduced by nerve injury. However, stabilization of mast cells did not alter the changes in expression or activity of MMP-2 and MMP-9 following nerve injury. CONCLUSION: These findings suggest that the contribution of MMP-9 upregulation to the inflammatory and degenerative changes that follow nerve injury is independent of mast cell activation.  相似文献   

20.
Matrix metalloproteinases (MMPs) have been reported to be involved in various inflammatory disorders. Previous studies revealed that MMP-2 and MMP-9 might play important roles in the breakdown of the blood-brain barrier (BBB) in the central nervous system (CNS) of patients with HTLV-I-associated myelopathy (HAM)/tropical spastic paraparesis (TSP). N-Biphenyl sulfonyl-phenylalanine hydroxamic acid (BPHA) selectively inhibits MMP-2, -9 and -14, but not MMP-1, -3 and -7. In the present study, we examined whether or not the selective MMP inhibitor BPHA could inhibit the heightened migrating activity of CD4+ T cells in HAM/TSP patients. The migration assay using an invasion chamber showed that migration of CD4+ T cells in HAM/TSP patients was inhibited by 25 microM BPHA. In addition, the inhibitory ratio of migrating CD4+ lymphocytes was higher in HAM patients compared to normal controls. These results suggest that the selective MMP inhibitor BPHA has therapeutic potential for HAM/TSP.  相似文献   

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