29 resultados para Promatrix Metalloproteinase-2


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We examined whether two functional polymorphisms (g.-1306 C> T and g.-735 C>T) in matrix metalloproteinase (MMP)-2 gene are associated with preeclampsia (PE) or gestational hypertension (GH), and whether they modify MMP-2 or tissue inhibitor of metalloproteinase (TIMP)-2 plasma concentrations in these hypertensive disorders of pregnancy. We studied 130 healthy pregnant (HP), 130 pregnant with GH, and 133 pregnant with PE. Genomic DNA was extracted from whole blood and genotypes for g.-1306 C>T and g.-735 C>T polymorphisms were determined by Real Time-PCR, using Taqman allele discrimination assays. Haplotypes were inferred using the PHASE program. Plasma MMP-2 and TIMP-2 concentrations were measured by ELISA. The main findings were that pregnant with PE have higher plasma MMP-2 and TIMP-2 concentrations than HP (P<0.05), although the MMP-2/TIMP-2 ratios were similar (P>0.05). Moreover, pregnant with GH have elevated plasma MMP-2 levels and MMP-2/TIMP-2 ratios compared to HP (P<0.05). While MMP-2 genotypes and haplotypes are not linked with hypertensive disorders of pregnancy, MMP-2 genotypes and haplotypes are associated with significant alterations in plasma MMP-2 and TIMP-2 concentrations in preeclampsia (P<0.05). Our findings may help to understand the relevance of MMP-2 and its genetic polymorphisms to the pathophysiology of hypertensive disorders of pregnancy. It is possible that patients with PE and the MMP-2 haplotype combining the C and T alleles for the g.-1306 C>T and g.-735 C>T polymorphisms may benefit from the use of MMPs inhibitors such as doxycycline. However, this possibility remains to be determined. (C) 2012 Elsevier Inc. All rights reserved.

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Increased reactive oxygen species (ROS) promote matrix metalloproteinase (MMP) activities and may underlie cardiomyocyte injury and the degradation of cardiac troponin I (cTI) during acute pulmonary thromboembolism (APT). We examined whether pretreatment or therapy with tempol (a ROS scavenger) prevents MMP activation and cardiomyocyte injury of APT. Anesthetized sheep received tempol infusion (1.0 mg kg(-1) min(-1), i.v.) or saline starting 30 min before or 30 min after APT (autologous blood clots). Control animals received saline. Hemodynamic measurements were performed. MMPs were studied in the right ventricle (RV) by gelatin zymography, fluorimetric activity assay, and in situ zymography. The ROS levels were determined in the RV and cTI were measured in serum samples. APT increased the pulmonary arterial pressure and pulmonary vascular resistance by 146 and 164 %, respectively. Pretreatment or therapy with tempol attenuated these increases. While APT increased RV + dP/dt (max), tempol infusions had no effects. APT increased RV MMP-9 (but not MMP-2) levels. In line with these findings, APT increased RV MMP activities, and this finding was confirmed by in situ zymography. APT increased the RV ROS levels and tempol infusion, before or after APT, and blunted APT-induced increases in MMP-9 levels, MMP activities, in situ MMP activities, and ROS levels in the RV. cTI concentrations increased after APT, and tempol attenuated these increases. RV oxidative stress after APT increases the RV MMP activities, leading to the degradation of sarcomeric proteins, including cTI. Antioxidant treatment may prevent MMP activation and protect against cardiomyocyte injury after APT.

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Altered matrix metalloproteinases (MMPs) levels are involved in cardiovascular diseases and increased MMP-9 levels enhance the cardiovascular risk in apparently healthy subjects. We investigated the effects of MMP-9 gene polymorphisms and haplotypes on the circulating MMP-9 levels in healthy black subjects and the effects of an MMP-2 polymorphism on the plasma MMP-2 concentrations. We studied 190 healthy subjects, nonsmokers, self-reported as blacks (18-63 years). Genotypes for the MMP-2 C-1306T polymorphism and the MMP-9 C-1562T, 90(CA)(14-24) and Q279R polymorphisms (rs243865, rs3918242, rs2234681, and rs17576, respectively) were determined by TaqMan (R) Allele Discrimination assay and real-time polymerase chain reaction or restriction fragment length polymorphism. Alleles for the 90(CA)(14-24) polymorphism were grouped as low (L) when there were < 21 and high (H) when there were >= 21 CA repeats. The plasma levels of MMP-2 and MMP-9 were determined by gelatin zymography. The software PHASE 2.1 was used to estimate the haplotypes frequencies. Although we found no effects of the MMP-9 C-1562T or the Q279R polymorphisms on MMP-9 levels, higher MMP-9 levels were associated with the HH genotype for the -90(CA)(14-24) polymorphism compared with the HL or LL genotypes. Lower MMP-9 levels were found in carriers of the CRL haplotype (combining the C, R, and L alleles for the MMP-9 polymorphisms) compared with the CRH haplotype. Consistent with this finding, the CRL haplotype was more commonly found in subjects with low MMP-9 levels. The MMP-2 C-1306T polymorphism had no effects on the plasma MMP-2 levels. Our results show that MMP-9 genetic variations modify MMP-9 levels in black subjects and may offer biochemical evidence implicating MMP-9 in the pathogenesis of cardiovascular diseases in blacks.

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Snake Venom Metalloproteinases (SVMPs) are the most abundant components present in Viperidae venom. They are important in the induction of systemic alterations and local tissue damage after envenomation. In the present study, a metalloproteinase named BpMPI was isolated from Bothropoides pauloensis snake venom and its biochemical and enzymatic characteristics were determined. BpMPI was purified in two chromatography steps on ion exchange CM-Sepharose Fast flow and Sephacryl S-300. This protease was homogeneous on SOS-PAGE and showed a single chain polypeptide of 20 kDa under non reducing conditions. The partial amino acid sequence of the enzyme showed high similarity with other SVMPs enzymes from snake venoms. BpMPI showed proteolytic activity upon azocasein and bovine fibrinogen and was inhibited by EDTA, 1,10 phenanthroline and beta-mercaptoethanol. Moreover, this enzyme showed stability at neutral and alkaline pH and it was inactivated at high temperatures. BpMPI was able to hydrolyze glandular and tissue kallikrein substrates, but was unable to act upon factor Xa and plasmin substrates. The enzyme did not induce local hemorrhage in the dorsal region of mice even at high doses. Taken together, our data showed that BpMP-I is in fact a fibrinogenolytic metalloproteinase and a non hemorrhagic enzyme. (C) 2011 Elsevier Inc. All rights reserved.

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Objective: Extracellular matrix homeostasis is strictly maintained by a coordinated balance between the expression of metalloproteinases (MMPs) and their regulators. The purpose of this study was to investigate whether MMP-2 and its specific regulators, TIMP-2, MT1-MMP and IL-8, are expressed in a reproducible, specific pattern and if the profiles are related to prognosis and clinical outcome of prostate cancer (PCa). Materials and Methods: MMP-2, TIMP-2, MT1-MMP and IL-8 expression levels were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) in freshly frozen malignant and benign tissue specimens collected from 79 patients with clinically localized PCa who underwent radical prostatectomies. The control group consisted of 11 patients with benign prostate hyperplasia (BPH). The expression profile of the MMP-2 and its regulators were compared using Gleason scores, pathological stage, pre-operative PSA levels and the final outcome of the PCa. Results: The analysis of 79 specimens of PCa revealed that MMP-2, TIMP-2, MT1-MMP and IL-8 were underexpressed at 60.0%, 72.2%, 62.0% and 65.8%, respectively, in malignant prostatic tissue in relation to BPH samples. Considering the prognostic parameters, we demonstrated that high Gleason score tumors (>= 7) over-expressed MMP-2 (p = 0.048) and TIMP-2 (p = 0.021), compared to low Gleason score tumors (< 7). Conclusion: We have demonstrated that MMP-2 and its regulators are underexpressed in PCa. Alternatively, overexpression of MMP-2 and TIMP-2 was related to higher Gleason score tumors. We postulate that alterations in metalloproteinase expression may be important in the control of tissue homeostasis related to prostate carcinogenesis and tumor behavior.

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We investigated whether three relevant polymorphisms (C-1562T, microsatellite - 90(CA)(14-24), and Q279R) in the MMP-9 gene, or MMP-9 haplotypes, are associated with migraine and affect MMP-9 and tissue inhibitor of MMPs (TIMP)-1 levels in patients with migraine. We studied 102 healthy women (controls) and 187 women with migraine (141 without aura - MWA, and 46 with aura - MA). Patients with MWA had higher plasma MMP-9 concentrations than patients with MA. Patients with MA had the highest TIMP-1 and lowest MMP-9/TIMP-1 ratios. The MMP-9 "C L Q" haplotype was associated with higher plasma MMP-9 concentrations in migraine patients. (C) 2012 Elsevier B.V. All rights reserved.

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Background: Altered levels of matrix metalloproteinases (MMPs) and their inhibitors, the tissue inhibitors of metalloproteinases (TIMPs), are involved in cardiovascular alterations associated with end stage kidney disease (ESKD). Genetic polymorphisms in MMP-9 gene affect MMP-9 levels. We examined how MMP-9 polymorphisms and haplotypes affect the changes in plasma MMP-9 and TIMP-1 levels found in patients with ESKD undergoing hemodialysis. Methods: We studied 94 ESKD patients undergoing hemodialysis for at least 3 months. MMP-9 and TIMP-1 were measured by ELISA in plasma from blood samples collected before and after a session of hemodialysis. Genotypes for three MMP-9 polymorphisms (C-1562T, rs3918242; -90 (CA)(14-24), rs2234681; and Q279R, rs17576) were determined by Taqman (R) Allele Discrimination Assay and real-time polymerase chain reaction. Haplotype frequencies were determined with the software program PHASE 2.1. Results: Hemodialysis increased MMP-9 and TIMP-1 levels (P<0.05). Genotypes had no effects on baseline MMP-9 and TIMP-1 levels (P>0.05). Hemodialysis increased MMP-9 and TIMP-1 levels in subjects with the CC (but not CT or TT) genotype for the C-1562T polymorphism (P<0.05), and increased MMP-9 levels in subjects with the QQ (but not QR or RR) genotype for the Q279R polymorphism (P<0.05), whereas the CA(n)(14-24) polymorphism had no major effects. While MMP-9 haplotypes had no effects on baseline MMP-9 levels (P>0.05), hemodialysis increased MMP-9 levels and MMP-9/TIMP-1 ratios in subjects carrying the CLQ haplotype (P = 0.0012 and P = 0.0045, respectively). Conclusion: ESKD patients with the QQ genotype for the Q279R polymorphism or with the CLQ haplotype are exposed to more severe increases in MMP-9 levels after hemodialysis. Such patients may benefit from the use of MMP inhibitors. (C) 2012 Elsevier B.V. All rights reserved.

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The pathogenic mechanisms of thromboangiitis obliterans (TAO) are not entirely known and the imbalance of matrix metalloproteinases (MMPs) plays a role in vascular diseases. We evaluated the MMP-2 and MMP-9 circulating levels and their endogenous tissue inhibitors of metalloproteinases (TIMP-1 and TIMP-2) in TAO patients with clinical manifestations. The study included 20 TAO patients (n = 10 female, n = 10 male) aged 38-59 years under clinical follow-up. The patients were classified into two groups: (1) TAO former smokers (n = 11) and (2) TAO active smokers (n = 9); the control group included normal volunteer non-smokers (n = 10) and active smokers without peripheral artery disease (n = 10). Patient plasma samples were used to analyze MMP-2 and MMP-9 levels using zymography, and TIMP-1 and TIMP-2 concentrations were determined by enzyme-linked immunosorbent assays. The analysis of MMP-2/TIMP-2 and MMP-9/TIMP-1 ratios (which were used as indices of net MMP-2 and MMP-9 activity, respectively) showed significantly higher MMP-9/TIMP-1 ratios in TAO patients (p < 0.05). We found no significant differences in MMP-2/TIMP-2 ratios (p > 0.05). We found higher MMP-9 levels and decreased levels of TIMP-1 in the TAO groups (active smokers and former smokers), especially in active smokers compared with the other groups (all p < 0.05). MMP-2 and TIMP-2 were not significantly different in patients with TAO as compared to the control group (p > 0.05). In conclusion, our results showed increased MMP-9 and reduced TIMP-1 activity in TAO patients, especially in active smokers compared with non-TAO patients. These data suggest that smoke compounds could activate MMP-9 production or inhibit TIMP-1 activity.

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Cervical cancer is the third most common cancer in women worldwide. Persistent infection with high-risk HPV types, principally HPV16 and 18 is the main risk factor for the development of this malignancy. However, the onset of invasive tumor occurs many years after initial exposure in a minority of infected women. This suggests that other factors beyond viral infection are necessary for tumor establishment and progression. Tumor progression is characterized by an increase in secretion and activation of matrix metalloproteinases (MMPs) produced by either the tumor cells themselves or tumor-associated fibroblasts or macrophages. Increased MMPs expression, including MMP-2, MMP-9 and MT1-MMP, has been observed during cervical carcinoma progression. These proteins have been associated with degradation of ECM components, tumor invasion, metastasis and recurrence. However, few studies have evaluated the interplay between HPV infection and the expression and activity of MMPs and their regulators in cervical cancer. We analyzed the effect of HPV16 oncoproteins on the expression and activity of MMP-2, MMP-9, MT1-MMP, and their inhibitors TIMP-2 and RECK in cultures of human keratinocytes. We observed that E7 expression is associated with increased pro-MMP-9 activity in the epithelial component of organotypic cultures, while E6 and E7 oncoproteins co-expression down-regulates RECK and TIMP-2 levels in organotypic and monolayers cultures. Finally, a study conducted in human cervical tissues showed a decrease in RECK expression levels in precancer and cancer lesions. Our results indicate that HPV oncoproteins promote MMPs/ RECK-TIMP-2 imbalance which may be involved in HPV-associated lesions outcome.

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This study aimed to evaluate the chemical interaction of collagen with some substances usually applied in dental treatments to increase the durability of adhesive restorations to dentin. Initially, the similarity between human dentin collagen and type I collagen obtained from commercial bovine membranes of Achilles deep tendon was compared by the Attenuated Total Reflectance technique of Fourier Transform Infrared (ATR-FTIR) spectroscopy. Finally, the effects of application of 35% phosphoric acid, 0.1M ethylenediaminetetraacetic acid (EDTA), 2% chlorhexidine, and 6.5% proanthocyanidin solution on microstructure of collagen and in the integrity of its triple helix were also evaluated by ATR-FTIR. It was observed that the commercial type I collagen can be used as an efficient substitute for demineralized human dentin in studies that use spectroscopy analysis. The 35% phosphoric acid significantly altered the organic content of amides, proline and hydroxyproline of type I collagen. The surface treatment with 0.1M EDTA, 2% chlorhexidine, or 6.5% proanthocyanidin did not promote deleterious structural changes to the collagen triple helix. The application of 6.5% proanthocyanidin on collagen promoted hydrogen bond formation. (c) 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.

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Background: Metastasis is the main factor responsible for death in breast cancer patients. Matrix metalloproteinases (MMPs) and their inhibitors, known as tissue inhibitors of MMPs (TIMPs), and the membrane-associated MMP inhibitor (RECK), are essential for the metastatic process. We have previously shown a positive correlation between MMPs and their inhibitors expression during breast cancer progression; however, the molecular mechanisms underlying this coordinate regulation remain unknown. In this report, we investigated whether TGF-beta 1 could be a common regulator for MMPs, TIMPs and RECK in human breast cancer cell models. Methods: The mRNA expression levels of TGF-beta isoforms and their receptors were analyzed by qRT-PCR in a panel of five human breast cancer cell lines displaying different degrees of invasiveness and metastatic potential. The highly invasive MDA-MB-231 cell line was treated with different concentrations of recombinant TGF-beta 1 and also with pharmacological inhibitors of p38 MAPK and ERK1/2. The migratory and invasive potential of these treated cells were examined in vitro by transwell assays. Results: In general, TGF-beta 2, T beta RI and T beta RII are over-expressed in more aggressive cells, except for T beta RI, which was also highly expressed in ZR-75-1 cells. In addition, TGF-beta 1-treated MDA-MB-231 cells presented significantly increased mRNA expression of MMP-2, MMP-9, MMP-14, TIMP-2 and RECK. TGF-beta 1 also increased TIMP-2, MMP-2 and MMP-9 protein levels but downregulated RECK expression. Furthermore, we analyzed the involvement of p38 MAPK and ERK1/2, representing two well established Smad-independent pathways, in the proposed mechanism. Inhibition of p38MAPK blocked TGF-beta 1-increased mRNA expression of all MMPs and MMP inhibitors analyzed, and prevented TGF-beta 1 upregulation of TIMP-2 and MMP-2 proteins. Moreover, ERK1/2 inhibition increased RECK and prevented the TGF-beta 1 induction of pro-MMP-9 and TIMP-2 proteins. TGF-beta 1-enhanced migration and invasion capacities were blocked by p38MAPK, ERK1/2 and MMP inhibitors. Conclusion: Altogether, our results support that TGF-beta 1 modulates the mRNA and protein levels of MMPs (MMP-2 and MMP-9) as much as their inhibitors (TIMP-2 and RECK). Therefore, this cytokine plays a crucial role in breast cancer progression by modulating key elements of ECM homeostasis control. Thus, although the complexity of this signaling network, TGF-beta 1 still remains a promising target for breast cancer treatment.

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Abstract Background Mature carotid plaques are complex structures, and their histological classification is challenging. The carotid plaques of asymptomatic and symptomatic patients could exhibit identical histological components. Objectives To investigate whether matrix metalloproteinase 9 (MMP-9), tissue inhibitor of MMP (TIMP), and cyclooxygenase-2 (COX-2) have different expression levels in advanced symptomatic carotid plaques, asymptomatic carotid plaques, and normal tissue. Methods Thirty patients admitted for carotid endarterectomy were selected. Each patient was assigned preoperatively to one of two groups: group I consisted of symptomatic patients (n = 16, 12 males, mean age 66.7 ± 6.8 years), and group II consisted of asymptomatic patients (n = 14, 8 males, mean age 67.6 ± 6.81 years). Nine normal carotid arteries were used as control. Tissue specimens were analyzed for fibromuscular, lipid and calcium contents. The expressions of MMP-9, TIMP-1 and COX-2 in each plaque were quantified. Results Fifty-eight percent of all carotid plaques were classified as Type VI according to the American Heart Association Committee on Vascular Lesions. The control carotid arteries all were classified as Type III. The median percentage of fibromuscular tissue was significantly greater in group II compared to group I (p < 0.05). The median percentage of lipid tissue had a tendency to be greater in group I than in group II (p = 0.057). The percentages of calcification were similar among the two groups. MMP-9 protein expression levels were significantly higher in group II and in the control group when compared with group I (p < 0.001). TIMP-1 expression levels were significantly higher in the control group and in group II when compared to group I, with statistical difference between control group and group I (p = 0.010). COX-2 expression levels did not differ among groups. There was no statistical correlation between MMP-9, COX-2, and TIMP-1 levels and fibrous tissue. Conclusions MMP-9 and TIMP-1 are present in all stages of atherosclerotic plaque progression, from normal tissue to advanced lesions. When sections of a plaque are analyzed without preselection, MMP-9 concentration is higher in normal tissues and asymptomatic surgical specimens than in symptomatic specimens, and TIMP-1 concentration is higher in normal tissue than in symptomatic specimens.

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This study evaluated the influence of fluoride on cell viability and activity of matrix metalloproteinases (MMP) -2 and -9 secreted by preosteoblasts. Preosteoblasts (MC3T3-E1 murine cell line) were cultured in MEM medium supplement with 10% Fetal Bovine Serum (FBS) and nucleosides/ribonucleosides without ascorbic acid. Adherent cells were treated with different concentrations of F (as sodium fluoride-NaF) in medium (5 x 10-6 M, 10-5 M, 10-4 M and 10-3 M) for 24, 48, 72 and 96 h at 37ºC, 5% CO2. Control cells were cultivated in MEM only. After each period, preosteoblast viability was assessed by MTT assay. MMP-2 and -9 activities were performed by gel zymography. Also, alkaline phosphatase (ALP) activity was quantified by colorimetry in all experimental groups. It was shown that cultured cells with the highest dose of F (10-3 M) for 96 h decreased preosteoblast viability while lower doses of F did not alter it, when compared to untreated cells. No differences were observed in ALP activity among groups. Moreover, compared to control, the treatment of cells with F at low dose slightly increased MMP-2 and -9 activities after 24 h. It was concluded that F modulates preosteoblast viability in a dose-dependent manner and also may regulate extracellular matrix remodeling.

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OBJECTIVE: Extracellular matrix homeostasis is strictly maintained by a coordinated balance between the expression of metalloproteinases (MMPs) and their regulators. The purpose of this study was to investigate whether MMP-2 and its specific regulators, TIMP-2, MT1-MMP and IL-8, are expressed in a reproducible, specific pattern and if the profiles are related to prognosis and clinical outcome of prostate cancer (PCa). MATERIALS AND METHODS: MMP-2, TIMP-2, MT1-MMP and IL-8 expression levels were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) in freshly frozen malignant and benign tissue specimens collected from 79 patients with clinically localized PCa who underwent radical prostatectomies. The control group consisted of 11 patients with benign prostate hyperplasia (BPH). The expression profile of the MMP-2 and its regulators were compared using Gleason scores, pathological stage, pre-operative PSA levels and the final outcome of the PCa. RESULTS: The analysis of 79 specimens of PCa revealed that MMP-2, TIMP-2, MT1-MMP and IL-8 were underexpressed at 60.0%, 72.2%, 62.0% and 65.8%, respectively, in malignant prostatic tissue in relation to BPH samples. Considering the prognostic parameters, we demonstrated that high Gleason score tumors (> 7) overexpressed MMP-2 (p = 0.048) and TIMP-2 (p = 0.021), compared to low Gleason score tumors (< 7). CONCLUSION: We have demonstrated that MMP-2 and its regulators are underexpressed in PCa. Alternatively, overexpression of MMP-2 and TIMP-2 was related to higher Gleason score tumors. We postulate that alterations in metalloproteinase expression may be important in the control of tissue homeostasis related to prostate carcinogenesis and tumor behavior.