Plasma MMP-9 Activity Research Articles

An observational study of matrix metalloproteinase (MMP)-9 in cystic fibrosis

BackgroundIn cystic fibrosis (CF), cross-sectional studies have reported sputum matrix metalloproteinase (MMP)-9 to be elevated and negatively correlated with FEV1. This longitudinal study examined the association between MMP-9 and tissue inhibitors of metalloproteinases (TIMPs) to prognostic parameters in CF. MethodA cross-sectional survey of CF and control subjects; CF patients were followed up for a median of 49months. MMP-9 and TIMP-1 and TIMP-2 were quantified in sputum and plasma. ResultsSeventy-three patients with CF, median age 22years, and 40 controls were recruited. Fifty-three of these CF patients were followed up. Prospectively, in CF subjects, plasma MMP-9 activity was adversely associated with FEV1 (β −1.15 (95% CI −2.10, −0.20), p=0.019) and rate of FEV1 decline, and plasma TIMP-1 was adversely associated with mortality: hazard ratio 3.66 (1.91–7.04), p<0.001. ConclusionsThese associations further justify investigation of MMP-9 and TIMP-1 as biomarkers for short- to medium-term FEV1 decline and mortality in patients with CF.

Postprandial plasma MMP-2 and MMP-9 activity following a high-fat versus a low-fat isoenergetic test-meal in lean healthy men

Background: Evidence suggests that an acute systemic inflammatory response is invoked following a high-energy meal. The gelatinases, matrix metalloproteinase-2 and -9 (MMP-2 and MMP-9) are important mediators of inflammation, are implicated in adipose tissue development, and are positively correlated with obesity. However, no studies to date have investigated the postprandial effects of a high-energy meal on circulating MMP-2 and MMP-9 in humans. Objective: To examine the postprandial effect of a high-energy (5MJ) test-meal on plasma MMP-2 and MMP-9 and to investigate the differential effect of a high-fat (HF) versus a low-fat (LF) test-meal on MMP-2 and MMP-9. Methods: Seventeen lean, healthy males (BMI 22± 0.5 kg/m2, age 21± 0.49y) participated in this single-blind, randomised, cross-over study. A HF test-meal (5001 kJ, 45 g fat) and an isoenergetic LF test-meal (5003 kJ, 15 g fat) were consumed by each subject on two separate occasions. Blood samples were collected by venepuncture at baseline (0 h), at 1 h and 3 h following ingestion of each test-meal. Plasma MMP-2 and MMP-9 activity was determined by gelatin zymography. Data underwent repeated measures ANOVA and were expressed as mean± SEM (P 0.05). When analysed independent of treatment, there was no significant change in plasma MMP-2 (time, P = 0.51) or MMP-9 (time, P = 0.52) over the 3 h postprandial period. There was no differential effect of the HF versus the LF test-meal (time× treatment P > 0.05) on circulating MMP-2 or MMP-9 at 1 h or at 3 h. Conclusion: This study showed no postprandial changes in circulating MMP-2 or MMP-9 following consumption of a high-energy meal nor any differential effect of a HF versus a LF test-meal on these parameters. Further research is necessary to elucidate the potential effect of dietary fat on gelatinases in humans.

The changes of matrix metalloproteinase-2 and -9 enzyme activities in the children with ventricular septal defect

Congenital heart disease (CHD) account for 1-3% population and ventricular septal defect (VSD) is the most common form of CHD that accounts for approximately 40% of total patients. Some of children with VSD can have spontaneous closure, but some don't. It is worth to study the biomarkers associated with VSD formation or closure. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases involved in breakdown, and physiological homeostasis of extracellular matrix. It has been reported that MMPs play the important roles in embryonic development, cardiomyocyte differentiation and causing cardiac tissue remodeling. Therefore, we studied the changes of plasma MMP-2 and MMP-9 activities in the patients with VSD. There were 96 children with perimembranous VSD enrolled in this study. We assigned our patients into three different groups according to the ratio of VSD diameter/diameter of aortic root (Ao). They were classified as below: Trivial group (VSD/Ao ratio < 0.2), Mild group (0.2 < VSD/Ao < 0.3), and Median group (0.3 < VSD/Ao). Plasma MMP-2 and MMP-9 activities of the patients were detected and assayed by gelatin zymography. The determined results show that there was a significant higher MMP-2 activity in the three groups when the results compared with that in the control group (p < 0.01). The changes of MMP-9 activity showed a similar trend as the finding in MMP-2 activity. After one year follow-up, it is found that significant difference of MMP-9 enzyme activity was found between VSD spontaneous closure and non-closure group (p < 0.01). In conclusion, a positive trend between the different size groups of VSD and activities of MMP-2 and MMP-9 was found. Our data hint that MMP-2 and MMP-9 expression may play a role in the pathogenesis of VSD. It is worth to further investigate the correlation between the changes of gelatinase and the mechanism of VSD formation or closure.

Increased matrix metalloproteinases-9 after sleep in plasma and in monocytes of obstructive sleep apnea patients

AimsObstructive sleep apnea is known to be a risk factor of coronary artery disease. Matrix metalloproteinases (MMPs) contribute to the instability and rupture of atherosclerotic plaque and acute coronary syndrome. The present study aimed to determine the correlation of MMPs including MMP-1, -2, -3 and -9 with the severity of obstructive sleep apnea (OSA). Main methodsPeripheral blood was sampled before and after overnight polysomnography study from OSA patients. Plasma was processed for ELISA and zymography. Monocytes were isolated from peripheral blood and RNA was prepared for RT/real-time PCR. Key findingsThe plasma level of MMP-9, but not MMP-1, -2, and -3 and TIMP-1 was remarkably increased in OSA patients. The plasma MMP-9 level was considerably higher after sleep and the net difference was most significant in patients with severe OSA. The plasma MMP-9 activity was also demonstrated to be significantly higher after sleep. The mRNA expression of MMP-9 in monocytes not only correlated well to the plasma MMP-9 level in the patients, but also was found to be significantly higher in patients with severe OSA. SignificanceThis study for the first time proves that the increase of plasma MMP-9 level in OSA patients is likely due to the up-regulated MMP-9 mRNA expression of monocytes in the peripheral blood.

Circulating Matrix Metalloproteinase-2 and -9 Enzyme Activities in the Children with Ventricular Septal Defect

Ventricular septal defect (VSD) is the most common form of congenital heart diseases. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases involved in causal cardiac tissue remodeling. We studied the changes of circulating MMP-2 and MMP-9 activities in the patients with VSD severity and closure. There were 96 children with perimembranous VSD enrolled in this study. We assigned the patients into three groups according to the ratio of VSD diameter/diameter of aortic root (Ao). They were classified as below: Trivial (VSD/Ao ratio ≤ 0.2), Small (0.2 < VSD/Ao ≤ 0.3) and Median (0.3 < VSD/Ao) group. Plasma MMP-2 and MMP-9 activities were assayed by gelatin zymography.There was a significant higher MMP-2 activity in the VSD (Trivial, Small and Median) groups compared with that in Control group. The plasma MMP-9 activity showed a similar trend as the findings in MMP-2 activity. After one year follow-up, a significant difference in the MMP-9 activity was found between VSD spontaneous closure and non-closure groups. In conclusion, a positive trend between the severity of VSD and activities of MMP-2 and MMP-9 was found. Our data imply that MMP-2 and MMP-9 activities may play a role in the pathogenesis of VSD.

Activity of matrix metalloproteinases MMP-2 and MMP-9 in bone marrow plasma of patients with acute myeloid leukemia

Prognostic significance of the ratio of MMP-2 and MMP-9 activities (MMP-2/MMP-9) have been investigated in bone marrow plasma (BMP) of 53 patients with acute myeloid leukemia (AML) using the method of zymography. During BMP collection 33 patients were diagnosed with complete remission (CR) and 22 patients without CR. The ratio MMP-2/MMP-9 was approximately 1.00 (the upper limit was equal 1.77) in the 75% of patients. At the same time the ratio was more than 3 times higher in 13 patients (25%): their minimal value was 1.80 (p < 0.001). In the group with high ratio MMP-2/MMP-9 only 3 patients were with CR, and 10 patients with resistant variant of AML. The median of the overall survival (OS) of these 10 patients was significantly lower than OS of other investigated AML patients (7.0 vs 33.5 months p < 0.001). Thus the high MMP-2/MMP-9 ratio (> or = 1.8) may be associated with unfavorable course of AML.

Leonurine (SCM-198) attenuates myocardial fibrotic response via inhibition of NADPH oxidase 4

In our previous studies, we have reported that leonurine, a plant phenolic alkaloid in Herba leonuri, exerted cardioprotective properties in a number of preclinical experiments. Herein, we investigated the roles and the possible mechanisms of leonurine for reducing fibrotic responses in angiotensin II (Ang II)-stimulated primary neonatal rat cardiac fibroblasts and post-myocardial infarction (MI) rats. In in vitro experiments performed in neonatal rat cardiac fibroblasts, leonurine (10–20μM) pretreatment attenuated Ang II-induced activation of extracellular signal-regulated kinase 1/2, production of intracellular reactive oxygen species (ROS), expression and activity of matrix metalloproteinase (MMP)-2/9, and expression of α-smooth muscle actin and types I and III collagen. A small interfering RNA-mediated knockdown strategy for NADPH oxidase 4 (Nox4) revealed that Nox4 was required for Ang II-induced activation of cardiac fibroblasts. In vivo studies using a post-MI model in rats indicated that administration of leonurine inhibited myocardial fibrosis while reducing cardiac Nox4 expression, ROS production, NF-κB activation, and plasma MMP-2 activity. In conclusion, our results provide the first evidence that leonurine could prevent cardiac fibrosis and the activation of cardiac fibroblasts partly through modulation of a Nox4–ROS pathway.

Increase in MMP-2 activity in overweight and obese women is associated with menopausal status

Background Metalloproteinases (MMPs) are synthesized in the subendothelium and are involved in the atherosclerosis and cardiovascular disease process because of their major significance in vascular remodeling and plaque rupture. MMPs are also synthesized in adipose tissue during angiogenesis; however, the role of these enzymes in obesity and insulin-resistant states is still controversial.Objective To evaluate MMP-2 activity in the circulation of overweight and obese women and in normal-weight controls, and to associate the levels of these factors with metabolic, adipose tissue and inflammation biomarkers.Methods Plasma MMP-2 activity, adiponectin and C-reactive protein concentration, lipoprotein profile and HOMA were determined in 39 healthy women (13 normal weight and 26 overweight/obese).Results Overweight/obese women were older (p <0.001) than normal-weight women; 20/26 of overweight/obese women were postmenopausal compared with 4/13 of normal-weight women. Overweight/obese women had significantly higher plasma activity of MMP-2 than controls (mean relative area: 0.81 (range 0.4–1.92) vs. 1.33 (range 0.4–3.1); p <0.005); this difference was lost after adjusting for menopausal status. MMP-2 activity positively correlated with waist circumference (p <0.002), HOMA (p <0.003), and high-sensitivity C-reactive protein (p <0.05), apolipoprotein B (p =0.006) and triglyceride/high density lipoprotein (HDL) cholesterol index (p <0.001), and negatively with HDL cholesterol (p <0.001), HDL2 cholesterol (p <0.008), HDL3 cholesterol (p <0.05) and adiponectin (p <0.05). The association with HOMA and adiponectin persisted even after adjusting for menopausal status.Conclusion Our finding of increased plasma activity of MMP-2 in overweight/obese women, associated with menopausal status, is important given that it fits in with an early stage of cardiovascular disease; the association of MMP-2 activity with obesity markers may be a link between adipose tissue and risk for cardiovascular disease.

Chronic cardiotoxicity of doxorubicin involves activation of myocardial and circulating matrix metalloproteinases in rats

To investigate the role of matrix metalloproteinases (MMPs) in the responses of rats to a prolonged doxorubicin (DOX) treatment. Male Wistar rats were used. DOX was administered by intraperitoneal injections of seven doses (cumulative dose was 15 mg/kg). Control animals were treated with saline. Tissue or plasma samples were collected at four and eight weeks after the application of the last dose. Protein levels were determined by immunoblot assay, and MMP activities were measured by gelatin zymography. Superoxide content was analyzed using a lucigenin chemiluminescence assay and superoxide dismutase (SOD) activities with a SOD assay kit. Qualitative structural alterations of the heart were characterized by transmission electron microscopy. Systolic blood pressure was higher in DOX-treated rats as compared with the control rats at 8 weeks after treatment. In contrast, there were no differences in the heart rate between the control and DOX-treated rats. DOX treatment caused marked heterogeneous subcellular alterations of cardiomyocytes and structural disorganizations of the cardiac extracellular space. The effects of DOX were linked to a stimulation of plasma MMP-2 and MMP-9 activities that had already increased by 4 weeks after the end of the treatment. In the left ventricle, however, DOX only led to increased MMP-2 activation at 8 weeks after the end of treatment. These changes in tissue MMP-2 were connected with stimulation of Akt kinase activation, inhibition of SOD, an increase in superoxide levels, induction of iNOS protein expression and caspase-3 activation. Our results show that MMPs are involved in the chronic cardiotoxicity of DOX in rats. The data also suggest that reactive oxygen species (superoxide), NO production (iNOS) and the Akt kinase pathway can modulate MMP-2 activities in rat hearts influenced by DOX.

Effect of resveratrol on the metastasis of 4T1 mouse breast cancer cellsin vitroandin vivo

We investigated the effects of resveratrol on metastasis in in vitro and in vivo systems. 4T1 cells were cultured in the presence of various concentrations (0-30 µmol/L) of resveratrol. For experimental metastasis, BALB/c mice were injected intravenously with 4T1 cells in the tail vein, and were orally administered various concentrations (0, 100, or 200 mg/kg Body weight) of resveratrol for 21 days. After resveratrol treatment, cell adhesion, wound migration, invasion, and MMP-9 activity were significantly decreased in a dose-dependent manner in 4T1 cells (P < 0.05). The numbers of pulmonary nodules were significantly decreased in mice fed the resveratrol (P < 0.05). The plasma MMP-9 activity was decreased in response to treatment with resveratrol in mice (P < 0.05). We conclude that resveratrol inhibits cancer metastasis both in vitro and in vivo, and this inhibition is likely due to the decrease in MMP-9 activity caused by resveratrol.

Ribavirin and Interferon Alter Mmp-9 Abundance In Vitro and in HIV–HCV-Coinfected Patients

Matrix metalloproteinases (MMPs) and their endogenous tissue inhibitors (TIMPs) are central to tissue remodelling during HIV-HCV infection. Here, we assess the potential for antiviral therapy to modulate MMP abundance in THP-1 monocyte/macrophages and LX-2 hepatic stellate cells, and in a coinfected patient cohort. THP-1 and LX-2 cells were treated with ribavirin (RBV)/interferon-α (IFN-α) and select HIV antivirals. Venous blood was reserved from HIV-HCV-coinfected patients, HIV- and HCV-monoinfected patients, and healthy controls, with the HIV-HCV cohort being sampled again at day 3 and 14 subsequent to the start of combination therapy with RBV/pegylated IFN-α. Samples were subjected to gelatin zymography, real-time RT-PCR and/or ELISA, where appropriate. RBV/IFN-α decreased MMP-9 activity, and increased MMP-9 mRNA and protein expression in THP-1 cells, but not in LX-2 cells. Decreases in MMP-9 activity were mediated by IFN-α, which also attenuated RBV induction of MMP-9 activity and protein expression in THP-1 cells. Saquinavir and lopinavir, HIV protease inhibitors, reduced MMP-9 activity in THP-1 and LX-2 cells, respectively. Plasma MMP-9 activity and expression was higher in HIV-HCV and HIV patients compared with HCV patients and healthy controls. MMP-2 and TIMP-2 levels were similar in all groups. RBV/pegylated IFN-α decreased plasma MMP-9 abundance in HIV-HCV patients. These data demonstrate that RBV/pegylated IFN-α reduce plasma MMP-9 abundance in vivo and may reduce its activity in vitro through immune cells, such as monocyte/macrophages, rather than hepatic stellate cells. The results of this study indicate that such therapy may mediate tissue remodelling associated with HIV-HCV coinfection through effects on MMP-9.

Imbalance of Metallaproteinase/Tissue Inhibitors of Metalloproteinase System in Renal Transplant Recipients With Chronic Allograft Injury

Introduction Nowadays, renal allografts continue to be lost at the rate of 2% to 4% per year beyond the first year after transplantation due to chronic allograft injury. Excessive accumulation of extracellular matrix results from overproduction and/or defective degradation by proteolytic enzymes, among which metalloproteinases (MMPs) play a major role. The aim of this study was to assess the role of MMPs in renal transplant recipients (RTR) in the context of allograft injury or proteinuria. Materials and methods Plasma and urine MMP-2 and MMP-9 and tissue inhibitors of metalloproteinases (TIMPs) were assessed by enzyme-linked immunoassay in 150 RTR including 66% males with an overall mean age of 49.2 ± 11.5 years. The subjects were examined at a mean of 73.4 ± 41.2 months (range = 12–240) after kidney transplantation. Thirty-seven healthy volunteers including 54% male with an overall mean age of 48.4 ± 14.1 years served as a control group. Results Renal transplant recipients displayed significantly decreased plasma MMP-2 activity compared with healthy controls ( P < .000) probably due to increased inhibitory plasma (p) TIMP-2 activity ( P = .0029), and lower plasma MMP-2:TIMP-2 index ( P < .0001). Plasma MMP-9 and pTIMP-1 activities were twofold increased in RTR compared with controls ( P = .0015 and P < .000) but with a nearly stable plasma MMP-9:TIMP-1 index ( P = NS). There was no difference between RTR and controls according to urine (u) MMP-2 activity, but uMMP-9 was increased in RTR compared with healthy controls ( P = .0032). Urine MMP-9 potential was probably diminished by increased uTIMPs (uTIMP-2, P = .017; uTIMP-1, P = .000), which contributed to graft impairment or proteinuria. Conclusion Our study revealed profibrotic MMP/TIMP constellations in RTR that show an imbalance in plasma MMP-2 and MMP-9 with increased plasma and urinary TIMPs. The net proteolytic potential of increased plasma and urinary MMP-9 may be diminished significantly by enhanced plasma and urine TIMP activities.

Red Ginseng Extract Reduced Metastasis of Colon Cancer Cells In Vitro and In Vivo

This study investigated the effect of red ginseng extract on metastasis of colon cancer cells in vitro and in vivo. Wound healing migration, cell motility, invasion, and activity, protein expression, and mRNA expression of matrix metalloproteinases (MMPs) were examined in SW480 human colon cancer cells. SW480 cells were cultured with or without 100 μg/L PMA in the absence or presence of various concentrations (100, 200, or 300 μg/mL) of red ginseng extract. Red ginseng extract treatment caused significant suppression of cell motility and invasion (p<0.05) in SW480 cells. Red ginseng extract inhibited MMP-2 and MMP-9 activity and their protein and mRNA expression in a dose-dependent manner (p<0.05) in SW480 cells. For experimental metastasis, BALB/c mice were injected intravenously with CT-26 mouse colon cancer cells in the tail vein, and were orally administered various concentrations (0, 75, 150, or 300 mg/kg body weight) of red ginseng extract for 3 weeks. Numbers of pulmonary nodules were significantly decreased in mice that were fed red ginseng extract (p<0.05). Plasma MMP-2 and MMP-9 activity significantly decreased in response to treatment with red ginseng extract in mice (p<0.05). These data suggest that red ginseng extract may be useful for prevention of cancer invasion and metastasis through inhibition of MMP-2 and MMP-9 pathways.

Evaluation of plasma activity of matrix metalloproteinase-2 and -9 in dogs with myxomatous mitral valve disease

To investigate whether plasma activity of matrix metalloproteinase (MMP)-2 and -9 was associated with severity of myxomatous mitral valve disease (MMVD) in dogs and to assess potential associations between MMP activity and dog characteristics, echocardiographic variables, systolic arterial blood pressure (SAP), heart rate, cardiac troponin I (cTnI) concentration, and C-reactive protein concentration. 75 client-owned dogs. Severity of MMVD was assessed by use of echocardiography. Plasma activity of latent (pro-MMP) and active MMP-2 and -9 was analyzed via zymography. Plasma concentration of cTnI was analyzed with a high-sensitivity cTnI assay, and C-reactive protein concentration was analyzed with a canine-specific ELISA. Pro-MMP-9, active MMP-9, and pro-MMP-2 were detected, but active MMP-2 was not. No significant differences were found in MMP concentrations among the 4 MMVD severity groups. Activity of pro-MMP-9 decreased with decreases in SAP and was higher in male dogs than in female dogs. Activity of MMP-9 decreased with increases in left ventricular end-systolic dimension and with decreases in SAP and cTnI concentration. Left ventricular end-systolic dimension was the variable most strongly associated with MMP-9 activity. No associations were found between the activity of pro-MMP-2 and investigated variables. Plasma MMP-9 activity decreased with increases in the end-systolic left ventricular internal dimension and decreases in SAP. Hence, evaluation of MMP-9 activity has the potential to provide unique information about the myocardial remodeling process in dogs with MMVD.

Matrix metalloproteinas-9 functional promoter polymorphism 1562C&gt;T increased risk of early-onset coronary artery disease

The Matrix metalloproteinase-9 functional promoter polymorphism 1562C>T may be considered an important genetic determinant of early-onset coronary artery disease (ECAD). In this study, association between MMP-9 1562C>T allele with plasma MMP-9 activity, homocysteine and lipid-lipoproteins level and ECAD in Iranian subjects was investigated. This case-control study consisted of 53 ECAD patients (age < 55 years) and unrelated late-onsets CAD (age>70 years) who angiographically had at least 50% stenosis. MMP-9 1562C>T polymorphism was detected by PCRRFLP, plasma MMP-9 activity, serum lipid and homocysteine levels were determined by gelatin gel zymography, enzyme assay and by HPLC, respectively. The presence of MMP-9 1562C>T allele was found to be associated with ECAD (OR=3.2, P=0.001). The ECAD patients with MMP-9 1562C>T allele had higher MMP-9 activity (P=0.001), LDL-C (P=0.045), TC (P=0.02) and homocysteine (P=0.01) levels than the LCAD subjects. MMP-9 1562C>T allele is a risk factor for ECAD. The carriers of this allele have high levels of MMP-9 activity, LDL-C, TC and homocysteine (P=0.01), thus, are more likely to develop myocardial infarction and CAD at young age (less than 55 years).

Neurovascular Injury in Acute Hyperglycemia and Diabetes: a Comparative Analysis in Experimental Stroke

Admission hyperglycemia impacts ischemic stroke deleteriously but the relative role of acute hyperglycemia (HG) versus diabetes in the pathogenesis of this poor outcome is not clear. To determine the effect of acute HG on neurovascular outcomes of stroke under control and diabetic conditions. Moderate acute HG (140-200 mg/dl) was achieved by glucose injection before middle cerebral artery occlusion (MCAO) in control Wistar and diabetic Goto-Kakizaki (GK) rats. Following 3 h MCAO/21 h reperfusion, we measured infarct size, hemorrhagic transformation (HT) frequency, excess hemoglobin, neurobehavioral outcome and plasma and MCA matrix metalloprotease (MMP) activity. Infarct size was significantly smaller in diabetic rats. Moderate acute HG increased neuronal damage in diabetic but not in control rats. HT frequency and hemoglobin were significantly higher in diabetic rats. HG augmented vascular damage in control rats and had no additional effect on bleeding in diabetic rats. Baseline plasma MMP-9 activity was significantly higher in diabetic rats. HG increased MMP-9 activity in control and diabetic rats. Neurological deficit was greater in diabetic rats and was worsened by HG. The finding that functional outcome is poorer in both acute HG and diabetes without a significant increase in infarct size suggests that amplified vascular damage contributes to neurological deficit in hyperglycemia. These results highlight the importance of vascular protection to improve neurological outcome in acute ischemic stroke.

Sodium Intake Is Associated with Carotid Artery Structure Alterations and Plasma Matrix Metalloproteinase-9 Upregulation in Hypertensive Adults1–3

The mechanisms by which dietary sodium modulates cardiovascular risk are not fully understood. This study investigated whether sodium intake is related to carotid structure and hemodynamics and to plasma matrix metalloproteinase (MMP) activity in hypertensive adults. One hundred thirty-four participants were cross-sectionally evaluated by clinical history, anthropometry, carotid ultrasound, and analysis of hemodynamic, inflammatory, and metabolic variables. Daily sodium intake (DSI) was estimated by 24-h recall, discretionary sodium, and a FFQ. In 42 patients, plasma MMP-2 and MMP-9 activities were also analyzed. The mean DSI was 5.52 ± 0.29 g/d. Univariate analysis showed that DSI correlated with common carotid artery systolic and diastolic diameter (r = 0.36 and 0.34; both P < 0.001), peak and mean circumferential tension (r = 0.44 and 0.39; both P < 0.001), Young's Elastic Modulus (r = 0.40; P < 0.001), intima-media thickness (r = 0.19; P < 0.05), and internal carotid artery resistive index (r = 0.20; P < 0.05). Multivariate analyses revealed that only artery diameter, circumferential wall tension, and Young's Elastic Modulus were independently associated with DSI. Conversely, plasma MMP-9 activity was associated with DSI (r = 0.53; P < 0.001) as well as with common carotid systolic diameter (r = 0.33; P < 0.05) and Young's Elastic Modulus (r = 0.38; P < 0.01). In conclusion, sodium intake is associated with carotid alterations in hypertensive adults independently of systemic hemodynamic variables. The present findings also suggest that increased MMP-9 activity might play a role in sodium-induced vascular remodeling.

Consistent Alterations of Circulating Matrix Metalloproteinases Levels in Untreated Hypertensives and in Spontaneously Hypertensive Rats: A Relevant Pharmacological Target

Inconsistent matrix metalloproteinases (MMPs) levels have been reported in hypertension, with higher, similar and lower MMPs levels reported in hypertensives compared with normotensives. Differences between studies may reflect lack of control of drug effects, accompanying diseases and pre-analytical issues. We compared MMP-2, MMP-8 and MMP-9 levels in 38 untreated hypertensive patients (with no other diseases) with those found in 33 normotensive controls. We also studied endogenous MMPs inhibitors (TIMP-1, TIMP-2 and alpha-2-macroglobulin-A2M). Additionally, we assessed MMPs and A2M levels in spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats. We hypothesized that similar MMPs/endogenous inhibitors' profiles would be found in this animal model of hypertension and in clinical hypertension. MMPs, TIMPs and A2M were measured in plasma samples with commercially available ELISA and gelatin zymography. We found unaltered MMP-2, MMP-8, TIMP-1, TIMP-2 and A2M levels in hypertension. However, hypertensives had higher MMP-9 levels and MMP-9/A2M ratios than normotensives. Moreover, while we found similar MMP-2 and A2M levels in SHR and WKY rats, we found higher MMP-9 levels and MMP-9/A2M ratios in SHR versus WKY rats. These findings show consistent abnormal net plasma MMP-9 (but not MMP-2) activity in clinical and experimental hypertension. These parallel alterations in clinical hypertension and in SHR suggest an important role for MMPs in hypertension. While MMPs may be a relevant pharmacological target, antihypertensive drugs that down-regulate MMPs may offer advantages in the management of this disease.

The determination of matrix metalloproteinase 9 activity and gene expression levels in Behcet’s disease patients with aneurysmal complications

The information concerning aneurysmal progress in Behcet's disease is still insufficient, while researches in the role of matrix metalloproteinases (MMPs) in aneurysmal formation are rapidly expanding. The goal of the present study is to investigate the role of metalloproteinase 9 (MMP-9) in vascular complications which is observed in 10% of Behcet's disease patients. Three groups have been studied; patients with Behcet's disease, patients with Behcet's disease who have vascular problems (vasculo-Behcet's), and patients with abdominal aortic aneurysm (AAA). The third group was used as a control. The activity and gene expression levels of MMP-9 in plasma have been determined. We showed that compared to AAA patients there was no difference in the MMP-9 activity in Behcet's disease patients (vascular and non-vascular). We also evaluated the gene expression level and activity of MMP-9 for every patient. The increase in the gene expression level for MMP-9 could only be detected at two patients. One of them was Behcet's, the other was AAA patient. It is surprising that MMP levels of these patients were different. While the patient with Behcet's had low protein level, another patient with AAA had high of MMP-9 level. This result suggested to us that the relationship between gene expression and active protein level is not correlated. It is not sufficient alone to determine MMPs levels for evaluating the pathogenesis. At the same time gene expression and the level of active protein should be assessed together.

The in vitro and in vivo anti-metastatic efficacy of oxythiamine and the possible mechanisms of action

This study examined the anti-metastatic effects of oxythiamine (OT) both in cell culture and in vivo. Cell culture results revealed that OT (0-20 microM) significantly inhibited the invasion and migration (IC(50) = 8.75 microM) of Lewis lung carcinoma (LLC) cells. These effects of OT were accompanied by the inhibition of metalloproteinases-2 and -9 (MMP-2, MMP-9), urokinase-type plasminogen activator (uPA) activities and by the increases in protein expression of tissue inhibitors of metalloproteinases-1 and -2 (TIMP-1, TIMP-2). We then implanted (s.c.) C57BL/6 mice with LLC cells and supplemented the mice with a low- or a high-dose of OT (250 or 500 mg/kg BW) daily for 5 wk. During the 5-wk period, OT supplementation decreased plasma MMP-2 activity in a dose-dependent manner, and this effect was significant after 4 wk of tumor cell implantation. Tumor metastasis was found to confine to the lungs of mice injected with the tumor cells. High-OT supplementation strongly lowered the number and area of tumors and inhibited protein expression of MMP-2 and MMP-9 in the lungs. In addition, high-OT supplementation markedly decreased the extent of proliferating cell nuclear antigen (PCNA) staining in the lungs. By contrast, OT supplementation increased TIMP-1 and -2 protein expression in the lungs. These results demonstrate that OT supplementation attenuates tumor cell metastasis, possibly via inhibition of protein expression of MMPs, extent of PCNA staining and via increase of proteins expression of TIMPs.