Matrix Metalloproteinase-8 Activity Research Articles

Matrix metalloproteinase-8 in early diagnostics of generalized periodontitis

The significant prevalence of periodontal diseases on the background of its tendency to increase makes the issue of search for early diagnostic methods and rational preventive therapeutic choice in generalized periodontitis to be topical. Purpose of the article is to determine the prospects for matrix metalloproteinase-8 (MMP-8) using for early diagnosis of generalized periodontitis according to the modern literature analysis over the past two years. The review presents data on the biological properties of MMP-8, its role in the processes of collagen destruction and also shows the results of clinical and experimental studies devoted to clarifying the role of MMP-8 in the pathogenesis of generalized periodontitis. It is noted that this enzyme content is indicative of the gums inflammatory process transformation to the alveolar bone destruction; therefore it can be considered as the prognostic marker for generalized periodontitis, even in the absence of pronounced clinical symptoms. Moreover, the increase in MMP-8 activity indicates the aggressive form of the disease requiring specific treatment. Particular attention is given to MMP-8 as the biochemical marker describing the features of generalized periodontitis course, in particular on the background of comorbid diseases such as diabetes, rheumatoid arthritis and in smokers. The relationship between MMP-8 level and other biochemical markers (interleukins, immunoglobulins, prostaglandins) is described in inflammatory-dystrophic lesions of the periodontal tissues. The comparative evaluation of the MMP-8 modern methods of determination effectiveness in various biological fluids has been carried out. Prospects and peculiarities of MMP-8 using in diagnostics and treatment for peri-implantitis, which are similar in pathogenesis to periodontitis, have been defined. Conclusions. It is worthwhile conducting the further studies of the MMP-8 possible use not only for the early diagnosis of generalized periodontitis, but also for its character prediction in order to develop the personal approach to patient care. Also, further studies in this direction will give an opportunity to move away from ambiguity and inconsistency in literature data and confirm the clinical effectiveness of MMP-8 for practical dentistry.

Microcystin-leucine-arginine causes blood-testis barrier disruption and degradation of occludin mediated by matrix metalloproteinase-8.

Microcystin-leucine-arginine (MC-LR) can cause male reproductive disorders. However, the underlying mechanisms are not yet fully understood. In this study, we aimed to investigate the effects of MC-LR on the integrity of blood-testis barrier (BTB) and the related molecular mechanisms. Both transepithelial electrical resistance measurement in vitro and electron microscope observation ex vivo revealed that MC-LR caused disruption of the tight junction between Sertoli cells, which was paralleled by the degradation of occludin. We observed increased expression of matrix metalloproteinase-8 (MMP-8) upon exposure to MC-LR, and confirmed that abrogation of MMP-8 activity by specific inhibitors as well as transfection with MMP-8 shRNA could abolish the degradation of occludin. Our data demonstrated that MC-LR up-regulated nuclear levels of c-Fos and c-Jun through activating ERK and JNK, and increased NF-κB levels by activating the phosphatidylinositol 3-kinase (PI3K)/AKT cascades. Enhanced binding of c-Fos and NF-κB to the promoter of MMP-8 promoted the transcription of MMP-8 gene. Furthermore, miR-184-3p was significantly downregulated in SC following exposure to MC-LR through targeting MMP-8 expression. Together, these results confirmed that MC-LR-induced MMP-8 expression was regulated at both transcriptional and post-transcriptional levels, which was involved in MC-LR-induced degradation of occludin and BTB destruction. This work may provide new perspectives in developing new diagnosis and treatment strategies for MC-induced male infertility.

Matrix metalloproteinase-8 activity in gingival crevicular fluid: development of a novel assay.

The matrix metalloproteinases (MMPs) play a role in regulating turnover and metabolism of connective tissues in health but they have also been implicated in a wide variety of pathological conditions, including periodontal disease. MMP-8 has been extensively studied in periodontal health and disease using ELISA, although this technique is limited by its inability to determine enzyme activity. The aim was to develop an assay specifically to measure MMP-8 activity and to demonstrate its use in the analysis of gingival crevicular fluid samples. A specific antibody was used to coat black 96-well microtitre plates to capture MMP-8 selectively. The activity of bound MMP-8 was measured using a fluorogenic substrate. Gingival crevicular fluid samples, from healthy and periodontally diseased sites, were collected using PerioPaper strips and tested for MMP-8 activity. Significantly higher MMP-8 activity was demonstrated in gingival crevicular fluid from periodontally diseased sites compared with healthy sites that exhibited basal or no MMP-8 activity. No cross-reactivity with other MMPs was noted. We show, for the first time, that MMP-8 activity can be specifically detected and quantified in gingival crevicular fluid samples. Measurement of MMP-8 activity could prove to be useful in monitoring periodontal disease progression.

Mechanistic investigations of matrix metalloproteinase-8 inhibition by metal abstraction peptide.

The mechanism of matrix metalloproteinase-8 (MMP-8) inhibition was investigated using ellipsometric measurements of the interaction of MMP-8 with a surface bound peptide inhibitor, tether-metal abstraction peptide (MAP), bound to self-assembled monolayer films. MMP-8 is a collagenase whose activity and dysregulation have been implicated in a number of disease states, including cancer metastasis, diabetic neuropathy, and degradation of biomedical reconstructions, including dental restorations. Regulation of activity of MMP-8 and other matrix metalloproteinases is thus a significant, but challenging, therapeutic target. Strong inhibition of MMP-8 activity has recently been achieved via the small metal binding peptide tether-MAP. Here, the authors elucidate the mechanism of this inhibition and demonstrate that it occurs through the direct interaction of the MAP Tag and the Zn(2+) binding site in the MMP-8 active site. This enhanced understanding of the mechanism of inhibition will allow the design of more potent inhibitors as well as assays important for monitoring critical MMP levels in disease states.

Effect of Roselle Extract in Expression of Matrix Metallo Proteinase - 8 (MMP-8) in Gingival Creviculer Fluid (GCF)

Background: This study is performed to determine the effect of roselle extract gel 10% toward the changing of MMP - 8 mRNA expression in Gingival Creviculer Fluid (GCF) in patient with gingivitis experience post acrylic crown insertion. Methods: This study is a pre and post test experimental research. Research subjects were 9 patients who experience gingivitis post acrylic crown insertion and divided in three groups (treatment with roselle gel, negative control, and positive control). GCF samples were taken with paper strips before and seven days after application of roselle extract gel 10%. The change of MMP-8 mRNA expression is tested using Real Time-Polymerase Chain Reaction (RT-PCR) method. The results then statistically tested using paired T test to see the effect of rosella extract toward MMP-8 activity. Result: The MMP - 8 mRNA expression in gingivitis post acrylic crown insertion crown in the experimental group is significantly decreased after application of roselle extract gel 10%, which also seen in the positive control group, but no changes observed in the negative control group. Conclusions: Roselle extract gel 10% is proven to be effective in reducing the activity of MMP - 8 in GCF.

Loss of matrix metalloproteinase-8 is associated with worsened recovery after ischemic kidney injury

Acute kidney injury (AKI) leads to chronic kidney disease. The mechanisms involved with recovery from AKI are poorly understood and molecular mediators responsible for healing and restoration of kidney function are understudied. We previously discovered differential expression of matrix metalloproteinase-8 (MMP-8) mRNA and protein in patients with severe sepsis associated AKI versus sepsis without AKI. Here, we demonstrate the involvement of MMP-8 in purely ischemic AKI. Mice subjected to 30 min of bilateral renal ischemia developed increased plasma creatinine and MMP-8 expression within 24 h versus sham controls. After an initial surge and subsequent return toward baseline, both kidney MMP-8 expression and activity exhibited a late increase (Days 5–7 post-ischemia reperfusion) in mice subjected to AKI. Neutrophil infiltration of the kidney was significantly higher after AKI in wild-type mice than in MMP-8 null mice, starting at 4 days. Additionally, MMP-8 null mice subjected to AKI demonstrated a persistent histopathologic and functional injury and worsened health (greater overall weight loss) versus wild-type cohorts after seven days. Taken together, our findings suggest that MMP-8 is involved with restoration of baseline kidney health after ischemic kidney injury and that a potential mechanism involves the interaction of MMP-8 and neutrophil recruitment to the site of injury.

Matrix Metalloproteinase 8 (Collagenase 2) Induces the Expression of Interleukins 6 and 8 in Breast Cancer Cells

Matrix metalloproteinase 8 (MMP-8) is a tumor-suppressive protease that cleaves numerous substrates, including matrix proteins and chemokines. In particular, MMP-8 proteolytically activates IL-8 and, thereby, regulates neutrophil chemotaxis in vivo. We explored the effects of expression of either a WT or catalytically inactive (E198A) mutant version of MMP-8 in human breast cancer cell lines. Analysis of serum-free conditioned media from three breast cancer cell lines (MCF-7, SK-BR-3, and MDA-MB-231) expressing WT MMP-8 revealed elevated levels of IL-6 and IL-8. This increase was mirrored at the mRNA level and was dependent on MMP-8 catalytic activity. However, sustained expression of WT MMP-8 by breast cancer cells was non-permissive for long-term growth, as shown by reduced colony formation compared with cells expressing either control vector or E198A mutant MMP-8. In long-term culture of transfected MDA-MB-231 cells, expression of WT but not E198A mutant MMP-8 was lost, with IL-6 and IL-8 levels returning to base line. Rare clonal isolates of MDA-MB-231 cells expressing WT MMP-8 were generated, and these showed constitutively high levels of IL-6 and IL-8, although production of the interleukins was no longer dependent upon MMP-8 activity. These studies support a causal connection between MMP-8 activity and the IL-6/IL-8 network, with an acute response to MMP-8 involving induction of the proinflammatory mediators, which may in part serve to compensate for the deleterious effects of MMP-8 on breast cancer cell growth. This axis may be relevant to the recognized ability of MMP-8 to orchestrate the innate immune system in inflammation in vivo.

Relation of plasma matrix metalloproteinase-8 levels late after myocardial infarction with left ventricular volumes and ejection fraction

Enhanced matrix metalloproteinase-8 (MMP-8) activity in the early post-myocardial infarction (MI) period has been related to early remodeling. However, it has been demonstrated that plasma MMP-8 level has a biphasic profile, and the relation between the late plasma levels and remodeling is unclear. We evaluated the plasma MMP-8 levels and its correlates 20±3 months after acute MI. 58 post-MI patients and 26 control subjects underwent quantitative single-photon emission computed tomography (SPECT) and echocardiography. The plasma MMP-8 levels were measured and its correlates were investigated. The MMP-8 levels were significantly higher in post-MI patients [median 3.88 ng/ml, interquartile range (1.88-6.43) vs. 0.67 ng/ml (0.34-2.47); p<0.001]. Plasma MMP-8 levels were significantly correlated with left ventricular ejection fraction (LVEF) (ρ=0.34, p=0.009), end diastolic volume index (EDVi) (ρ=-0.39, p=0.002) and end systolic volume index (ESVi) (ρ=-0.40, p=0.002). Plasma MMP-8 levels were found to still be high in post-MI patients 20±3 months after the index event. The levels were significantly correlated with left ventricular volume indices and LVEF. We speculate that, in contrast to the relation between the higher early MMP-8 activity and the extent of cardiac remodeling, higher late levels may be associated with relative preservation of left ventricular systolic function.

Genetics and genomics in pediatric septic shock

Pediatric septic shock continues to be an important public health problem. Several investigative groups have applied genetic and genomic approaches as a means of identifying novel pathways and therapeutic targets, discovery of sepsis-related biomarkers, and identification of septic shock subclasses. This review will highlight studies in pediatric sepsis with a focus on gene association studies and genome-wide expression profiling. A summary of published literature involving gene association and expression profiling studies specifically involving pediatric sepsis and septic shock. Several polymorphisms of genes broadly involved in inflammation, immunity, and coagulation have been linked with susceptibility to sepsis, or outcome of sepsis in children. Many of these studies involve meningococcemia, and the strongest association involves a functional polymorphism of the plasminogen activator inhibitor-1 promoter region and meningococcal sepsis. Expression profiling studies in pediatric septic shock have identified zinc supplementation and inhibition of matrix metalloproteinase-8 activity as potential, novel therapeutic approaches in sepsis. Studies focused on discovery of sepsis-related biomarkers have identified interleukin-8 as a robust outcome biomarker in pediatric septic shock. Additional studies have demonstrated the feasibility and clinical relevance of gene expression-based subclassification of pediatric septic shock. Pediatric sepsis and septic shock are increasingly being studied by genetic and genomic approaches and the accumulating data hold the promise of enhancing our future approach to this ongoing clinical problem.

A novel role for matrix metalloproteinase-8 in sepsis*

Matrix metalloproteinase-8 messenger RNA expression was previously found to be increased in whole blood of children with septic shock. The impact of this finding on the severity and inflammatory response to sepsis is unknown. Here, we investigate the relationship between matrix metalloproteinase-8 and disease severity in children with septic shock. We further corroborate the role of matrix metalloproteinase-8 in sepsis in a murine model. Retrospective observational clinical study and randomized controlled laboratory experiments. Pediatric intensive care units and an animal research facility at an academic children's hospital. Patients age ≤10 yrs admitted to the intensive care unit with a diagnosis of septic shock. For laboratory studies, we utilized male mice deficient for matrix metalloproteinase-8 and male wild-type C57BL/6J mice. Blood from children with septic shock was analyzed for matrix metalloproteinase-8 messenger RNA expression and matrix metalloproteinase-8 activity, and correlated with disease severity based on mortality and degree of organ failure. A murine model of sepsis was used to explore the effect of genetic and pharmacologic inhibition of matrix metalloproteinase-8 on the inflammatory response to sepsis. Finally, activation of nuclear factor-κB was assessed both in vitro and in vivo. Increased matrix metalloproteinase-8 mRNA expression and activity in septic shock correlates with decreased survival and increased organ failure in pediatric patients. Genetic and pharmacologic inhibition of matrix metalloproteinase-8 leads to improved survival and a blunted inflammatory profile in a murine model of sepsis. We also identify matrix metalloproteinase-8 as a direct in vitro activator of the proinflammatory transcription factor, nuclear factor-κB. Matrix metalloproteinase-8 is a novel modulator of inflammation during sepsis and a potential therapeutic target.

Gender-associated differences in plaque phenotype of patients undergoing carotid endarterectomy

Carotid endarterectomy to prevent a stroke is less beneficial for women compared with men. This benefit is lower in asymptomatic women compared with asymptomatic men or symptomatic patients. A possible explanation for this gender-associated difference in outcome could be found in the atherosclerotic carotid plaque phenotype. We hypothesize that women, especially asymptomatic women, have more stable plaques than men, resulting in a decreased benefit of surgical plaque removal. Carotid endarterectomy specimens of 450 consecutive patients (135 women, 315 men) were studied. The culprit lesions were semi-quantitatively analyzed for the presence of macrophages, smooth muscle cells, collagen, calcifications, and luminal thrombus. Plaques were categorized in three phenotypes according to overall presentation and the amount of fat. Protein was isolated from the plaques for determination of interleukin-6 (IL-6) and IL-8 concentrations and matrix metalloproteinase-8 (MMP-8) and MMP-9 activities. Atheromatous plaques (>40% fat) were less frequently observed in women than in men (22% vs 40%; P < .001). In addition, plaques obtained from women more frequently revealed low macrophage staining (11% vs 18%; P = .05) and strong smooth muscle cell staining (38% vs 24%; P = .001). Compared with men, women had a lower plaque concentration of IL-8 (P = .001) and lower MMP-8 activity (P = .01). The observed differences were most pronounced in asymptomatic women, who showed the most stable plaques, with an atheromatous plaque in only 9% of cases compared with 39% in asymptomatic men (P = .02). In addition, a large proportion of plaques obtained from asymptomatic women showed high smooth muscle cell content (53% vs 30%; P = .03) and high collagen content (55% vs 24%; P = .003). All relations between gender and plaque characteristics, except for MMP-8, remained intact in a multivariate analysis, including clinical presentation and other cardiovascular risk factors. Carotid artery plaques obtained from women have a more stable, less inflammatory phenotype compared with men, independent of clinical presentation and cardiovascular risk profile. Asymptomatic women demonstrate the highest prevalence of stable plaques. These findings could explain why women benefit less from carotid endarterectomy compared with men.

Unstable Carotid Plaques Exhibit Raised Matrix Metalloproteinase-8 Activity

Unstable Carotid Plaques Exhibit Raised Matrix Metalloproteinase-8 Activity

Unstable carotid plaques exhibit raised matrix metalloproteinase-8 activity

One early phase of atherosclerosis involves the recruitment of inflammatory cells from the circulation and their transendothelial migration. This process is predominantly mediated by cellular adhesion molecules, which are expressed on the vascular endothelium and on circulating leukocytes in response to several inflammatory stimuli. Selectins (P, E and L) and their ligands (mainly P-selectin ligand) are involved in the rolling and tethering of leukocytes on the vascular wall. Intercellular adhesion molecules (ICAMs) and vascular cell adhesion molecules (VCAM-1), as well as some of the integrins, induce firm adhesion of inflammatory cells at the vascular surface, whereas platelet endothelial cellular adhesion molecules (PECAM-1) are involved in extravasation of cells from the blood compartment into the vessel and underlying tissue. For most of the cellular adhesion molecules, except integrins, soluble forms have been identified in the circulation although their origins are not fully understood. Several lines of evidence support a crucial role of adhesion molecules in the development of atherosclerosis and plaque instability. Expression of VCAM-1, ICAM-1 and L-selectin has been consistently observed in atherosclerotic plaques. There is accumulating evidence from prospective studies for a predictive role of elevated circulating levels of sICAM-1 in initially healthy people, and of sVCAM-1 in patients at high risk or with overt CAD. A large number of common polymorphisms has been identified in the genes encoding the different adhesion molecules, but studies investigating their relationship either with soluble forms or with CAD are still sparse and often based on small samples. Further research is needed to firmly establish the potential clinical and therapeutic utilities of (soluble) adhesion molecules, but results in both fields hold the promise that in future, adhesion molecules might add information for clinical risk prediction and serve as therapeutic targets.

Unstable carotid plaques exhibit raised matrix metalloproteinase-8 activity.

The fibrous cap of atherosclerotic plaques is composed predominantly of type I and III collagen. Unstable carotid plaques are characterized by rupture of their cap, leading to thromboembolism and stroke. The proteolytic mechanisms causing plaque disruption are undefined, but the collagenolytic matrix metalloproteinase (MMP) -1, -8, and -13 may be implicated. The aim of this study was to quantify the concentrations of these collagenases in carotid plaques and to determine their relationship to markers of plaque instability. Atherosclerotic plaques were collected from 159 patients undergoing carotid endarterectomy. The presence and timing of carotid territory symptoms were ascertained. Preoperative embolization was recorded by transcranial Doppler. Each plaque was assessed for histological features of instability. Plaque MMP concentrations were quantified with ELISA. Significantly higher concentrations of active MMP-8 were observed in the plaques of symptomatic patients (20.5 versus 11.4 ng/g; P=0.0002), in plaques of emboli-positive patients (22.7 versus 13.5 ng/g; P=0.0037), and in those plaques showing histological evidence of rupture (20.8 versus 14.7 ng/g; P=0.0036). No differences were seen in the levels of MMP-1 and MMP-13. Immunohistochemistry, in situ hybridization, and colocalization studies confirmed the presence of MMP-8 protein and mRNA within the plaque, which colocalized with macrophages. These data suggest that the active form of MMP-8 may be partly responsible for degradation of the collagen cap of atherosclerotic plaques. This enzyme represents an attractive target for drug therapy aimed at stabilizing vulnerable plaques.

Induction of Matrix Metalloproteinase-8 in Human Fibroblasts by Basic Calcium Phosphate and Calcium Pyrophosphate Dihydrate Crystals: Effect of Phosphocitrate

Although matrix metalloproteinase-8 (MMP-8) was regarded as the exclusive product of the neutrophils, recent studies have shown that it is also expressed in articular chondrocytes, rheumatoid synovial fibroblasts and endothelial cells. Our aim was to determine the expression of MMP-8 in human fibroblasts (HF) by reverse transcription/polymerase chain reaction (RTIPCR), Northern and Western blotting methods and MMP-8 activity assay. We have shown the expression of MMP-8 in HF and its dose-dependent upregulation by basic calcium phosphate (BCP) and calcium pyrophosphate dihydrate (CPPD) crystals which arc markers of severe joint degeneration in ostcoarthritis. These effects require new protein synthesis and are reversed by phosphocitrate (PC). The results also show that this fibroblast MMP-8 is distinct from the neutrophil MMP-8 and from the fibroblast MMP-1. These results indicate that MMP-8 may play a significant role in the pathogenic effects of the crystals in ostcoarthritis.