The 5A6A polymorphism in the promoter of the stromelysin-1 (MMP3) gene as a risk factor for restenosis

Incidence and risk factors of in-stent restenosis after percutaneous coronary intervention in patients from southern China

Background

In-stent restenosis (ISR) remains a challenge for coronary artery disease (CAD) patients who undergo percutaneous coronary intervention (PCI) with stents, and risk factors for ISR are controversial. This study aimed to investigate the incidence and risk factors of ISR in patients from southern China.

Methods

In this retrospective study, patients diagnosed as acute coronary syndromes (ACS) and underwent successful PCI with drug-eluting stent (DES) and conducted a follow-up coronary angiography in Center for Cardiovascular Diseases of Meizhou People’s Hospital at the period of January 1st, 2016 to January 1st, 2021 were included for analysis. The clinical and angiographic factors were compared between patients in ISR ( +) and ISR (−) groups. The association between variables and ISR was evaluated by multivariate logistic regression model.

Result

A total of 341 ACS patients who had been installed at least 1 stent were included in this study. The follow-up time was 34.2 ± 17.2 months. During the follow-up period, 62 (18.2%) patients experienced ISR, and the average time for ISR was 32.8 months; the incidence of ISR for left main coronary artery, left anterior descending coronary artery, left circumflex artery coronary artery and right coronary artery were 6.7%, 20.9%, 19.4% and 14.4%, respectively; left ventricular ejection fraction (LVEF), stent number, stent type, statin therapy, antiplatelet therapy were significantly different between patients in ISR ( +) and ISR (−) group. Multivariate logistic analysis suggested that LVEF and stent number were significantly correlated with ISR.

Conclusion

Our study revealed the incidence and risk factors of ISR in patients from southern China. Our data suggested that LVEF and stent number were independent risk factors associated with ISR.

Matrix Metalloproteinase-3 (MMP-3) Polymorphisms Are Associated with Prolonged ECG-Derived QTc Interval: A Cross-Sectional Study of the Australian Rural Population

Matrix metalloproteinases (MMPs) are enzymes that are integral in extracellular matrix (ECM) remodeling. In age or disease, ECM may become dysregulated and contribute to fibrosis, which impairs cardiac electrical conduction. Two alleles regulate matrix metalloproteinase-3 (MMP-3) activity: one with five adenosine bases (5A; associated with higher MMP-3 activity and decreased fibrosis) and another with six adenosine bases (6A; associated with lower MMP-3 activity and increased fibrosis). Here, we determined whether ECG-derived QTc and related parameters are associated with the MMP-3 5A/6A genotype in a cross-section of the Australian rural population. A retrospective cross-sectional population was obtained from the Charles Sturt University Diabetes Screening Research Initiative. Genotype and resting 12-lead ECG parameters of 295 participants were analyzed. Amongst these participants, 85 individuals carried the 5A/5A genotype, 141 individuals carried the 5A/6A genotype, and 65 individuals carried the 6A/6A genotype. Compared to 5A/5A genotype carriers, 5A/6A genotype carriers had a significantly longer QTc duration by 9.50 ms (95% CI: 3.48-15.52, p = 0.002), whilst 6A/6A genotype carriers had an even longer QTc duration by 12.19 ms (95% CI: 5.04-19.34, p = 0.001). We found an association between MMP-3 5A/6A polymorphisms and QTc, independent of adjustments for age, gender, alcohol consumption, smoking status, body mass index and blood pressure.

Is coronary artery tortuosity a predisposing factor for drug-eluting stent restenosis?

BACKGROUND

Coronary artery tortuosity (CAT) is a relatively common finding on coronary angiography and may be associated with impaired left ventricular relaxation and coronary ischemia However, the significance of CAT remains unknown. This study aimed to investigate whether the severity of tortuosity in the targeted coronary segment is a predictor of stent restenosis.

METHODS

The study included a total of 637 patients undergoing drug-eluting stent implantation due to stable or unstable angina and who had no native coronary artery stenosis on their last coronary angiogram. The patients were separated into two groups: 312 patients with in-stent restenosis and 325 patients without in-stent restenosis. All patients underwent computed tomography (CT) coronary angiography after invasive angiography and CAT was calculated using the computer software.

RESULTS

Patients with in-stent restenosis had higher CAT than those without restenosis (1.25 ± 0.11 vs. 1.11 + 0.07, p < 0.001). Multivariate Cox regression analysis showed that the tortuosity index (hazard ratio [HR]: 1.246 95% confidence interval [CI]: 1.127-1.376 p < 0.001) and the circumflex lesion (HR: 1.437 95% CI: 1.062-1.942 p = 0.019) were independently associated with in-stent restenosis. With the threshold value of severe tortuosity set at 1.15, the prediction of could be made with 81% sensitivity and 80% specificity.

CONCLUSION

The severity of tortuosity is proportional to coronary in-stent stenosis in patients with stable and unstable angina pectoris undergoing drug-eluting stent implantation for a severe single coronary artery.

Preventing treatment failures in coronary artery disease: what can we learn from the biology of in-stent restenosis, vein graft failure, and internal thoracic arteries?

Coronary artery disease (CAD) remains one of the most important causes of morbidity and mortality worldwide, and the availability of percutaneous or surgical revascularization procedures significantly improves survival. However, both strategies are daunted by complications which limit long-term effectiveness. In-stent restenosis (ISR) is a major drawback for intracoronary stenting, while graft failure is the limiting factor for coronary artery bypass graft surgery (CABG), especially using veins. Conversely, internal thoracic artery (ITA) is known to maintain long-term patency in CABG. Understanding the biology and pathophysiology of ISR and vein graft failure (VGF) and mechanisms behind ITA resistance to failure is crucial to combat these complications in CAD treatment. This review intends to provide an overview of the biological mechanisms underlying stent and VGF and of the potential therapeutic strategy to prevent these complications. Interestingly, despite being different modalities of revascularization, mechanisms of failure of stent and saphenous vein grafts are very similar from the biological standpoint.

Sex differences in circulating proteins in heart failure with preserved ejection fraction

BACKGROUND

Many patients with heart failure with preserved ejection fraction (HFpEF) are women. Exploring mechanisms underlying the sex differences may improve our understanding of the pathophysiology of HFpEF. Studies focusing on sex differences in circulating proteins in HFpEF patients are scarce.

METHODS

A total of 415 proteins were analyzed in 392 HFpEF patients included in The Metabolic Road to Diastolic Heart Failure: Diastolic Heart Failure study (MEDIA-DHF). Sex differences in these proteins were assessed using adjusted logistic regression analyses. The associations between candidate proteins and cardiovascular (CV) death or CV hospitalization (with sex interaction) were assessed using Cox regression models.

RESULTS

We found 9 proteins to be differentially expressed between female and male patients. Women expressed more LPL and PLIN1, which are markers of lipid metabolism; more LHB, IGFBP3, and IL1RL2 as markers of transcriptional regulation; and more Ep-CAM as marker of hemostasis. Women expressed less MMP-3, which is a marker associated with extracellular matrix organization; less NRP1, which is associated with developmental processes; and less ACE2, which is related to metabolism. Sex was not associated with the study outcomes (adj. HR 1.48, 95% CI 0.83-2.63), p = 0.18.

CONCLUSION

In chronic HFpEF, assessing sex differences in a wide range of circulating proteins led to the identification of 9 proteins that were differentially expressed between female and male patients. These findings may help further investigations into potential pathophysiological processes contributing to HFpEF.

A potential role for the CDH13/CDH15 gene in repeat revascularization after first percutaneous coronary intervention

Aim: Major drawbacks of percutaneous coronary intervention are the high occurrence of repeat revascularization due to restenosis and disease progression. The aim of this study was to find genetic indicators to predict the risk of repeat revascularization. Materials & methods: From April 2015 to June 2016, 143 patients with percutaneous coronary intervention with genetic test results were enrolled. SNPs were measured by OmniZhongHua-8, and the SNPs in pathways genes related to known stenosis-related processes from the KEGG, BioCarta and Gene Cards databases were selected for analysis. Results: Cell-extracellular matrix interactions were the pathways with the most significant SNP (CDH15 rs72819363) association with repeat revascularization. Compared with CDH13 rs11859453G carriers, the adjusted odds ratio for A carriers was 0.25 and 0.33 at 18 and 30 months. Conclusion: We demonstrated a potential role of the cell-extracellular matrix interactions pathway and the possible biomarker CDH13/CDH15 in the development of coronary repeat revascularization.

Association study of matrix metalloproteinase 3 5A/6A polymorphism with in-stent restenosis after percutaneous coronary interventions in a Han Chinese population

Objective

We aimed to investigate the association between the 5A/6A promoter polymorphism in the matrix metalloproteinase 3 (MMP3) gene and in-stent restenosis (ISR) in a regional Chinese population.

Methods

A total of 818 patients who underwent primary implantation of drug-eluting stents were enrolled and received a 6-month follow-up angiography and DNA genotyping of the 5A/6A polymorphism.

Results

ISR was found in 36.9% of all patients (302 ISR vs. 516 no ISR). The genotype proportion of 6A6A was significantly increased in ISRs (74.2% ISR vs. 66.8% no ISR), whereas the allele frequency of 5A was significantly decreased in ISR patients (25.8%) compared with controls who did not undergo ISR (33.1%).

Conclusions

Our data indicate that the MMP3 6A6A genotype is a genetic susceptibility factor for ISR after coronary stent placement, but the 5A allele can lower the risk for patients within 6 months after stenting. Therefore, genotyping 5A/6A in the MMP3 promoter is suggested for patients who undergo coronary stent implantation.

MMP1 and MMP3 gene polymorphisms in patients with acute coronary syndromes

Matrix metalloproteinases (MMPs) are the group of proteolytic enzymes that break down the components of the connective tissue matrix leading to unstable atherosclerotic plaques. The aim of this study was to examine the association between MMP1-1607dupG (rs1799750) and MMP3-1171dupA (rs3025058) gene polymorphisms and acute coronary syndromes (ACS) in the form of unstable angina. This study included 197 patients with ACS in the form of unstable angina confirmed by coronary angiography (defined by >70% stenosis in at least one major coronary artery) and 144 healthy controls. There was no statistically significant difference in the distribution of the MMP1-1607dupG (rs1799750) polymorphism between patients with unstable angina and the control group. With regard to the MMP3-1171dupA (rs3025058) polymorphism, a significant increase in the frequency of the 6A/6A genotype among patients with unstable angina was detected. This association was confirmed in multivariate logistic regression analysis, where male sex and rs3025058 6A/6A genotype were significantly associated with an increased risk of ACS. © 2017 IUBMB Life, 69(11):850-855, 2017.

Association between MMP-3 and MMP-9 polymorphisms and coronary artery disease

Matrix metalloproteinase (MMP)-3 and MMP-9 polymorphisms are characterized by plaque stability in coronary arteries. The aim of the current study was to investigate the 5A/6A polymorphism in the MMP-3 gene and C/T polymorphism in the MMP-9 gene in patients with coronary artery disease (CAD). The study population consisted of 400 patients who underwent coronary angiography. There were two groups consisting of 200 consecutive patients with CAD, presenting with stable angina pectoris, and 200 consecutive patients exhibiting normal coronary arteries. Two single nucleotide polymorphisms in the MMP gene, MMP-3 and MMP-9, were detected using a polymerase chain reaction-restriction fragment length polymorphism assay. Mean age, gender distribution, smoking status, presence of diabetes mellitus and hypercholesterolemia were identified to be similar between the groups. One hundred and twenty seven (63.5%) patients had hypertension in the CAD group, whereas only 55 (27.5%) patients had hypertension in the control group (P<0.001). No significant difference in frequency of alleles and genotypes of MMP-9 C→T between the CAD and control groups was identified. The 5A allele frequency of MMP-3 in the CAD group was significantly higher when compared with the control group (P<0.001; odds ratio=2.18). The genotype frequency of MMP-3 5A/5A in the CAD group was significantly higher when compared with the controls (P=0.005). When compared with the homozygous wild-type (6A/6A) genotype of the MMP-3 gene, the cumulative frequency of heterozygote and homozygote genotypes of the MMP-3 gene was significantly higher in the CAD compared with the control group (P<0.001). Thus, the present study demonstrated that the 5A/5A and 6A/5A+5A/5A genotypes of the MMP-3 gene were associated with an increased risk of CAD.

Understanding and managing in-stent restenosis: a review of clinical data, from pathogenesis to treatment

The lumen diameter reduction after percutaneous coronary intervention (PCI) is well known as "restenosis". This phenomenon is due to vessel remodeling/recoil in case of no-stent strategy or, in case of stent employ, "neointimal proliferation" that consists in an excessive tissue proliferation in the luminal surface of the stent otherwise by a further new-occurring atherosclerotic process called "neoatherosclerosis". The exact incidence of in-stent restenosis (ISR) is not easy to determine caused by different clinical, angiographic and operative factors. In the pre-stent era the occurrence of restenosis ranged between 32-55% of all angioplasties, and drop to successively 17-41% in the bare metal stents (BMS) era. The advent of drug-eluting stent (DES), especially 2nd generation, and drug-coated balloon (DCB) further reduce restenosis rate until <10%. We here review the main characteristics of this common complication of coronary interventions, from its pathogenesis to the most appropriate treatment strategy.

Stromelysin-1 5A/6A and eNOS T-786C Polymorphisms, MTHFR C677T and A1298C Mutations, and Cigarette-Cannabis Smoking: A Pilot, Hypothesis-Generating Study of Gene-Environment Pathophysiological Associations With Buerger’s Disease

Buerger’s disease (BD) etiologies are poorly understood. Beyond smoking cessation, medical-surgical treatments have limited success. We hypothesized that mutations associated with arterial vasospasm (stromelysin-1 5A/6A, eNOS T-786C) and C677T-A1298C methylene tetrahydrofolate reductase (MTHFR) interacted with cigarette-cannabis smoking, reducing vasodilatory nitric oxide (NO), promoting arterial spasm-thrombosis. Of 21 smoking BD patients (14 men [2 siblings], 7 women; 20 white, 1 African-American), compared to 21 age-gender-race matched healthy controls, 5A/6A stromelysin- 1 homozygosity was present in 7 of 21 (33%) BD cases versus 5 of 21 (24%) controls (risk ratio 1.4; 95% confidence interval [CI] 0.5-3.7), and eNOS T-786C homozygosity was present in 3 of 21 (14%) BD cases versus 1 of 21 (5%) controls (risk ratio 3.0; 95% CI 0.3-26.6). C677T MTHFR homozygosity or compound C677T-A1298C heterozygosity was present in 7 of 21 cases (33%) versus 11 of 21 controls (52%) (risk ratio 0.6; 95% CI 0.3-1.3). In 18 patients who stopped and 3 who continued smoking, all stromelysin-1 5A/6A and/or eNOS heterozygotes-homozygotes, superficial phlebitis, lower limb gangrenous ulcers, and intractable ischemic rest pain with arterial occlusion progressed despite conventional medical therapy, threatening amputation. In 15 patients, to increase vasodilatory NO via endothelial NO synthase, l-arginine (15 g/day) was given, along with folic acid (5 mg), vitamin B6 (100 mg), and B12 (2000 mg/day) to optimize homocysteine metabolism and reduce asymmetric dimethylarginine, a NO synthase inhibitor. Unexpectedly quickly and strikingly, within 8 weeks to 8 months receiving l-arginine-folic acid, 11 of 15 treated patients improved with uniform pain reduction, ulcer healing, and in 5, full recovery of previously absent peripheral pulses. In smokers homo/heterozygous for stromelysin-1 5A/6A and eNOS T-786C mutations, we speculate that the development and severity of BD are related to a gene-environment vasospastic interaction with reduced NO-mediated vasodilatation. Increasing NO production by l-arginine while optimizing homocysteine metabolism by folic acid-B6-B12 may have therapeutic benefit. Further blinded, placebo-controlled studies are needed to determine whether our observations can be generalized to larger BD cohorts.

The Relation between eNOS -786 C/T, 4 a/b, MMP-13 rs640198 G/T, Eotaxin 426 C/T, -384 A/G, and 67 G/A Polymorphisms and Long-Term Outcome in Patients with Coronary Artery Disease

Aim. The purpose of this study is to determine the association between eotaxin 426 C/T, −384 A/G, 67 G/A, eNOS −786 T/C, 4 a/b, and MMP-13 rs640198 G/T and prognosis of patients with known CAD. Methods. From total of 1161 patients referred to coronary angiography, 532 patients with angiographically confirmed CAD were selected. Their long-term outcome was followed up using hospital database. Subsequent events were assessed in this study: death or combined endpoint-myocardial infarction, unstable angina pectoris, revascularization, heart failure hospitalization, and cardioverter-defibrillator implantation. Results. The multivariate Cox regression model identified age, smoking, and 3-vessel disease as significant predictors of all-cause death. Further analysis showed that eotaxin 67 G/A (GA + AA versus GG) and eotaxin −384 A/G (GG versus GA + AA) were significant independent prognostic factors when added into the model: HR (95% CI) 2.81 (1.35–5.85), p = 0.006; HR (95% CI) 2.63 (1.19–5.83), p = 0.017; eotaxin −384 A/G was significantly associated with the event-free survival, but it did not provide the prognostic information above the effect of two- or three-vessel disease. Conclusion. The A allele in eotaxin 67 G/A polymorphism is associated with worse survival in CAD patients.

MMP-1 and -3 haplotype is associated with congenital anomalies of the kidney and urinary tract

BACKGROUND

Congenital anomalies of the kidney and urinary tract (CAKUT) are a common cause of progressive chronic kidney disease that may lead to end-stage renal disease and renal replacement therapy in childhood. Altered expression or activity of matrix metalloproteinases (MMPs) have been found in CAKUT. The MMP-1, -3, and -8 polymorphisms studied here are located in the gene promoters and alter expression. Our aim was to investigate associations of MMP polymorphisms, solely and in haplotypes, with CAKUT in children.

METHODS

A case-control study with 101 pediatric patients and 281 controls was performed. The MMP-1 (-1607 1G/2G), -3 (5A/6A), and -8 (-799 C/T) genotypes were determined by PCR-restriction fragment length polymorphism.

RESULTS

We found statistically significant associations of MMP-3 5A/6A polymorphism (p < 0.0001) and 1G-(1607)-6A haplotype, with no preferences for MMP-8 -799C or T alleles, with CAKUT (OR = 2.93, 95 % CI 1.43-5.98, adjusted for gender, p = 0.003) and with obstructive uropathies in a subgroup of patients (OR = 4.57, 95 % CI 2.74-7.61, adjusted for gender, p < 0.0001).

CONCLUSIONS

MMP-3 genotypes and MMP-3 and -1 haplotypes encompassing either MMP-8 -799C or T alleles were associated with CAKUT and obstructive uropathies in pediatric patients. Still, functional and association studies are needed to elucidate evident roles of MMPs in CAKUT.

Matrix metalloproteinases in coronary artery disease

Matrix metalloproteinases (MMP) are a family of zinc-containing endoproteinases that degrade extracellular matrix (ECM) components. MMP have important roles in the development, physiology and pathology of cardiovascular system. Metalloproteases also play key roles in adverse cardiovascular remodeling, atherosclerotic plaque formation and plaque instability, vascular smooth muscle cell (SMC) migration and restenosis that lead to coronary artery disease (CAD), and progressive heart failure. The study of MMP in developing animal model cardiovascular systems has been helpful in deciphering numerous pathologic conditions in humans. Increased peripheral blood MMP-2 and MMP-9 in acute coronary syndrome (ACS) may be useful as noninvasive tests for detection of plaque vulnerability. MMP function can be modulated by certain pharmacological drugs that can be exploited for treatment of ACS. CAD is a polygenic disease and hundreds of genes contribute toward its predisposition. A large number of sequence variations in MMP genes have been identified. Case-control association studies have highlighted their potential association with CAD and its clinical manifestations. Although results thus far are inconsistent, meta-analysis has demonstrated that MMP-3 Glu45Lys and MMP-9 1562C/T gene polymorphisms were associated with CAD risk.

The polymorphisms of the MMP-1 and the MMP-3 genes and the risk of pelvic organ prolapse

INTRODUCTION AND HYPOTHESIS

To investigate the associations between single nucleotide polymorphism (SNP) type 1G/2G at position -1607/-1608 of the matrix metalloproteinase (MMP)-1 gene and SNP type 5A/6A at position -1612/-1617 of the MMP-3 gene and the development of pelvic organ prolapse (POP) in women.

METHODS

133 patients with symptomatic POP were included in the study group. The control group consisted of 132 women with a normal pelvic floor. 1G/2G MMP-1 and 5A/6A MMP-3 SNPs were determined by polymerase chain reaction (PCR) and restriction fragments length polymorphism analysis.

RESULTS

When estimated individually none of the investigated SNPs were associated with POP. The combined MMP-1/MMP-3 SNP analysis showed that the following polymorphic pairs were overrepresented in women with POP: 1G/2G -5A/6A, 2G/2G -5A/6A, 2G/2G -5A/5A, 1G/1G -6A/6A, p=0.005.

CONCLUSIONS

The combined effect of -1607/-1608 MMP-1 and -1612/-1617 MMP-3 SNPs may contribute to the development of POP in some women.

Role of matrix metalloproteinase 3 gene promoter polymorphism in chronic pancreatitis

AIM

To study the role of 5A/6A polymorphism of matrix metalloproteinase (MMP-3) and their levels in the pathogenesis of chronic pancreatitis (CP).

METHODS

One hundred and twenty CP patients and an equal number of age and sex-matched healthy controls were included in the study. Genotypes were determined for 5A/6A allele of MMP-3 gene by allele specific PCR (AS-PCR). The serum MMP-3 levels were estimated using sandwich ELISA method.

RESULTS

The distribution of the genotypes of the 5A/6A polymorphism in both control and study patients was similar (p = 0.523). Within the disease group, patients with older age, early onset of the disease, and addictions such as smoking and alcohol consumption had higher levels as compared to those who did not have these features.

CONCLUSION

We conclude that functional polymorphism of MMP-3 (5A/6A) is not associated with CP. However, the higher levels within the disease group indicate its possible role in the disease process.

MMP-3 (5A/6A) polymorphism does not influence human smooth muscle cell invasion

BACKGROUND

Stromelysin (MMP-3) is an important regulator of vascular smooth muscle cell (SMC) invasion, a key contributor to saphenous vein (SV) bypass graft failure. The 5A allele of the common -1612 MMP-3 5A/6A promoter polymorphism reportedly confers increased promoter activity, MMP-3 tissue expression, and susceptibility to a number of vascular pathologies. The aim of this study was to determine whether the MMP-3 5A/6A polymorphism directly influences endogenous MMP-3 expression levels and, consequently, cell invasion, in SV-derived SMC cultured from patients with different genotypes.

MATERIAL AND METHODS

Genotyping of 226 patients revealed -1612 MMP-3 5A/6A genotype frequencies of 20.8% 5A/5A, 52.7% 5A/6A, and 26.5% 6A/6A. Using a standardized, controlled protocol, we investigated cytokine- and growth factor-induced MMP-3 expression (real-time polymerase chain reaction [RT-PCR], ELISA) and SV-SMC invasion (Boyden chamber with Matrigel barrier) using cultured SV-SMC from patients with different MMP-3 genotypes.

RESULTS

Despite observing a strong correlation between MMP-3 mRNA levels and MMP-3 protein secretion, no significant differences were apparent in MMP-3 expression levels or cell invasion between cells with different MMP-3 5A/6A genotypes.

CONCLUSIONS

Our data suggest that the MMP-3 5A/6A promoter polymorphism in isolation does not influence levels of MMP-3 secretion or cellular invasion in human SV-SMC.

Interleukin 8 gene polymorphisms and susceptibility to restenosis after percutaneous coronary intervention

Interleukin-8 is a strong mediator of inflammation and has been implicated in the biochemical pathways involved in a wide range of inflammatory diseases including atherosclerosis. We investigated the potential influence of two common functional polymorphisms of the interleukin (IL)-8 gene: -251A/T and 781C/T on susceptibility to in stent restenosis (ISR) following percutaneous coronary intervention (PCI). The hypothesis was tested by screening for the prevalence of the above polymorphisms in 201 coronary artery disease (CAD) patients subjected to PCI and presenting with symptoms or signs of recurrent ischemia. Patients were angiographically re-evaluated and formed the ISR group (n = 73) and the non-ISR group (n = 128) based on the presence or absence of ISR. One hundred and forty-seven subjects without angiographic evidence of CAD formed a reference control group (non-CAD group). A borderline statistically significant higher frequency of the TT(251)TT(781) combined genotype was observed in patients with ISR on re-evaluation compared with patients with normal follow-up angiography. The predominance of TT(251)TT(781) was independent of conventional risk factors for cardiovascular disease. Consequently, T(251)T(781) haplotype was significantly more common in the ISR group. The above observations indicate that the genetic diversity of the IL-8 gene influences patient susceptibility to ISR and suggests the implication of IL-8-mediated pathways in the process of ISR. However, the rarity of T(251)T(781) haplotype makes any clinical application of the above observations unfeasible.

Allele-specific regulation of matrix metalloproteinase-3 gene by transcription factor NFkappaB

Background

Matrix metalloproteinase-3 (MMP3) is implicated in the pathogenesis and progression of atherosclerotic lesions. Previous studies suggested that MMP3 expression is influenced by a polymorphism (known as the 5A/6A polymorphism) in the promoter of the MMP3 gene and that this polymorphism is located within a cis-element that interacts with the transcription factor NFκB. In the present study, we sought to investigate whether MMP3 and NFκB were co-localized in atherosclerotic lesions and whether NFκB had differential effects on the two alleles of the MMP3 5A/6A polymorphism.

Methodology/Principal Findings

Immunohistochemical examination showed that MMP3 and both the NFκB p50 and p65 subunits were expressed abundantly in macrophages in atherosclerotic lesions and that MMP3 expression was co-localized with p50 and p65. Chromatin immunoprecipitation experiments showed interaction of p50 and p65 with the MMP3 promoter in macrophages, with greater binding to the 5A allele than to the 6A allele. Reporter gene assays in transiently transfected macrophages showed that the 5A allele had greater transcriptional activity than the 6A allele, and that this allele-specific effect was augmented when the cells were treated with the NFκB activator lipopolysaccharides or co-transfected with p50 and/or p65 expressing plasmids, but was reduced when the cells were treated with the NFκB inhibitor 6-Amino-4-(4-phenoxyphenylethylamino)-quinazoline or transfected with a dominant negative mutant of IkB kinase-β.

Conclusion

These results corroborate an effect of the 5A/6A polymorphism on MMP3 transcription and indicate that NFκB has differential effects on the 5A and 6A alleles.

Inhibition of smooth muscle cell migration and neointima formation in vein grafts by overexpression of matrix metalloproteinase-3

OBJECTIVE

Saphenous vein grafts suffer from neointima formation following bypass surgery. Matrix metalloproteinases (MMPs) play important roles in this process. We examined MMP-3 for its therapeutic potential to prevent smooth muscle cell migration and neointima formation in venous bypass grafts using adenovirus-mediated gene transfer.

METHODS

Human aortic smooth muscle cells (HASMC) were transduced with adenoviral vectors encoding ss-galactosidase (Ad.ssgal) [corrected] or human MMP-3 (Ad.hMMP-(3)), [corrected] and characterized for migration in the amniotic membrane stroma as an in vitro model of the vascular wall. Cholesterol-fed New Zealand white rabbits underwent jugular vein bypass grafting into carotid arteries. Before insertion, grafts were incubated ex vivo with either Ad.ssgal [corrected] or hMMP-3. Transgene expression was characterized by immunohistochemistry and in situ zymography. Grafts (n = 6) were explanted after 28 days and intimal hyperplasia was quantified.

RESULTS

Migration of HASMC was significantly reduced when transduced with Ad.hMMP-(3) [corrected] compared to controls (P < .001). Immunocytochemistry of Ad.hMMP-(3) [corrected] transduced venous grafts localized this protein to the intima. In situ-zymography showed increased MMP activity in the intima of Ad.hMMP-(3) [corrected] transfected grafts. Stenosis degree (P = .001), intima/media-ratio (P = .023) and lesion thickness (P = .003) were significantly reduced in grafts transduced with Ad.MMP-3 in comparison to controls. There was no difference inside control groups.

CONCLUSION

MMP-3 overexpression inhibits formation of intimal hyperplasia in arterialized vein grafts. Adenovirus mediated gene transfer of MMP-3 may be of clinical use to prevent vein graft stenosis following bypass surgery.

Association of the matrix metalloproteinase-3 (-439C/G) promoter polymorphism with Kawasaki disease in Korean children

Kawasaki disease (KD) is a multisystemic vasculitis that often includes coronary artery involvement. The serum levels of matrix metalloproteinase (MMP)-3 and -9 are significantly elevated in KD patients, and polymorphisms in the genes encoding MMP-3 and MMP-9 have been associated with the susceptibility, severity, and progression of atherosclerosis and aneurysm. However, the association between MMP-3 gene polymorphisms and development of aneurysm is somewhat controversial in a number of diseases. Ninety-seven children with KD and 194 children with congenital heart disease (CHD) were included in this study. Echocardiography was used to examine all children in the KD group for coronary artery aneurysm. Genotyping of the MMP-3 (-439C/G) promoter polymorphism was performed using the single-base extension method, and serum MMP-3 levels were estimated using the sandwich enzyme immunoassay method. There was no significant difference in MMP-3 (-439C/G) genotypes between KD and control groups. There was no association between this MMP-3 polymorphism and development of coronary aneurysm in KD. Serum MMP-3 levels were significantly higher in KD patients compared to control subjects. Among the KD patients, serum MMP-3 levels were higher in children with genotypes CG+GG compared to the CC group, but this difference was not significant. Although further large-scale studies will be required to fully examine the relationship between MMP-3 gene polymorphisms and coronary artery lesions (CAL) in KD, the present findings suggest that while MMP-3 may play a role in the pathogenesis of KD, there is no apparent association between CAL and the MMP-3 (-439C/G) gene polymorphism in Korean children with KD.

ALOX5AP variants are associated with in-stent restenosis after percutaneous coronary intervention

BACKGROUND

Use of drug-eluting stents (DES) has reduced in-stent restenosis after percutaneous coronary intervention (PCI); however, DES are associated with late stent thrombosis. There is no accurate way to predict in-stent restenosis, although risk factors for atherosclerosis overlap those for in-stent restenosis. Therefore, we evaluated atherosclerosis candidate genes for association with in-stent restenosis.

METHODS

We identified 46 consecutive cases that had undergone PCI with bare-metal stents who subsequently developed symptomatic in-stent restenosis of the target lesion (>/=75% luminal narrowing) within 6 months. Forty-six age-, race-, vessel-diameter- and sex-matched controls without in-stent restenosis after PCI with bare-metal stent were also identified. Single-nucleotide polymorphisms (SNPs, N=82) from 39 candidate atherosclerosis genes were genotyped. Multivariable logistic regression models were used to test for association.

RESULTS

Five SNPs were associated with in-stent restenosis. Three ALOX5AP SNPs were most strongly associated, two with increased risk (OR 3.74, p=0.01; OR 3.46, p=0.02), and the third with decreased risk of in-stent restenosis (OR 0.09, p=0.004). Two ALOX5AP haplotypes were associated with in-stent restenosis (HapB: OR 3.13, p=0.03); and a haplotype similar to HapA: OR 0.14, p=0.0009).

CONCLUSIONS

ALOX5AP, a gene within the inflammatory leukotriene pathway linked to and associated with coronary atherosclerosis, is also associated with in-stent restenosis. Genotyping these variants may help identify those at risk for in-stent restenosis who would benefit most from use of DES.

Association of OAZ1 Gene Polymorphisms With Subclinical and Clinical Vascular Events

OBJECTIVE

Proliferation and migration of vascular smooth muscle cells (VSMCs) are striking features shared by vascular ageing, atherosclerosis, and in-stent restenosis. VSMC biology depends in part on polyamines whose metabolism is closely regulated by ornithine decarboxylase antizyme 1 (OAZ1). Therefore, we sought for association between OAZ1 gene polymorphisms and various outcomes involving VSMC proliferation.

METHODS AND RESULTS

Systematic screening of the OAZ1 gene enabled to detect 21 variants. The impact of 4 selected tag polymorphisms (+849C/T, +851G/T, +1804G/A, and +2222A/G) was evaluated in 3 independent association studies. In a sample of 205 patients, the +2222G allele was associated with an increased risk of 6-month coronary in-stent restenosis (OR [95%CI]=2.1 [1.2 to 3.6]; P=0.0071). In a sample of 1001 subjects participating to the EVA study, the +2222G allele was longitudinally associated with a 4-year increase in common carotid intima-media thickness (P=0.047). In a case-control study (466 cases versus 466 controls), the risk of coronary heart disease associated with the +2222G allele was 1.3 (95%CI=[1.1 to 1.6]; P=0.026). No other significant association was consistently detected.

CONCLUSIONS

We identified the OAZ1+2222A/G polymorphism as a potential genetic marker of vascular events. Our findings strengthen the hypothesis that the polyamine metabolism plays a role in vascular diseases.

Plasma metalloproteinase-12 and tissue inhibitor of metalloproteinase-1 levels and presence, severity, and outcome of coronary artery disease

Several matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) have been implicated in the development and outcome of coronary artery disease (CAD). We investigated whether MMP-12 and TIMP-1 levels were associated with risk, severity, and outcome of CAD. Plasma MMP-12 and TIMP-1 levels are measured in 50 and 44 patients with CAD, respectively, by enzyme-linked immunosorbent assay. Of all patients, 16 were taking statins. Patients who were not on statins were classified into 3 groups according to number of >50% stenotic vessels. Compared with 29 volunteers without CAD, patients without statins (n = 34) had higher MMP-12 concentrations (1.71 vs 1.08 ng/ml, p = 0.021). MMP-12 levels were significantly lower in patients with than in those without statin treatment (0.99 vs 1.71 ng/ml, p = 0.008). There was no association between MMP-12 levels and number of >50% stenotic vessels. MMP-12 concentrations were not associated with outcome of CAD. However, plasma TIMP-1 levels were associated with restenosis independently of number of stenotic vessels and age (p = 0.035) but not with risk or severity of CAD. In conclusion, plasma MMP-12 concentration was associated with the presence of CAD. Statin therapy decreases plasma MMP-12 levels in patients with CAD. Increased TIMP-1 levels may prevent restenosis after angioplasty.

Genetic analysis of fluvastatin response and dyslipidemia in renal transplant recipients

The Assessment of Lescol in Renal Transplantation clinical trial demonstrated the efficacy of fluvastatin in reducing cardiovascular (CV) disease in renal transplant recipients. The study included a voluntary pharmacogenetic component, enrolling 1,404 patients, which allowed association testing of baseline measures and longitudinal analysis of the 707 fluvastatin-treated and 697 placebo-treated individuals. A candidate gene approach, examining 42 polymorphisms in 18 genes, was used to test for association between selected polymorphisms and major adverse cardiac events, graft failure, change in LDL and HDL cholesterol, and baseline LDL and HDL cholesterol. Reported associations between cholesteryl ester transfer protein (CETP) and baseline HDL cholesterol were replicated, with four previously implicated single nucleotide polymorphisms significantly associated in males and one in females; tests of reported associations between CETP and CV disease yielded varying results. We found no evidence for genetic factors affecting fluvastatin response. Polymorphisms in 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) previously reported to affect the efficacy of pravastatin did not show a similar effect on the reduction of LDL cholesterol by fluvastatin.

The role of genetic variants of matrix metalloproteinases in coronary and carotid atherosclerosis

Current evidence suggests that matrix metalloproteinases (MMPs) have a role in early atherosclerosis, plaque rupture and myocardial infarction. Polymorphisms in MMP genes have been examined for associations with atherosclerosis, but interpretation is complicated by methodological issues. This article presents a systematic review of these association studies and a meta-analysis of available data for polymorphisms where a sufficient number of studies was available. The 5A allele of the MMP3 5A/6A polymorphism was associated with acute myocardial infarction (odds ratio (OR) 1.26, 95% confidence interval (CI) 1.1 to 1.4, p<0.001), suggesting its role in plaque rupture. There was no association with the functional MMP9 -1562C/T polymorphism (OR 1.11, 95% CI 1.0 to 1.3, p = 0.18). Current data provide evidence for the role of MMP3 polymorphism in plaque destabilisation, but elucidation of the role of other MMP gene variants in atherosclerosis will depend on better study design, including a larger sample size, extensive screening of individual genes with haplotype analysis and replication of studies to avoid publication bias.

Present status of outcome prediction of invasive coronary treatment by using genetic markers

A growing number of studies suggest that the outcome after invasive coronary treatment may be in part genetically determined. Here, we review the present status of outcome prediction of invasive coronary treatments by using genetic markers. Although some studies found an association between one or another genetic marker with one or another clinical endpoint, many other studies found no such relations; to date, none of the genetic markers that have been investigated in association studies are used in routine clinical practice to prospectively assess the prognosis following invasive coronary treatment or to decide upon therapeutic strategies. Many associations between genetic markers and certain clinical endpoints were initially reported in small studies but could not be confirmed in larger ones. Some of these discrepancies may be explained by publication bias. Some genetic variants may have true effects on clinical endpoints, which, albeit biologically interesting, do not bear much clinical relevance. On the other hand, many-if not most-studies that have been published to date are more or less grossly underpowered and very rarely report on the results of an a priori power analysis. Thus, there is still a need for further high-quality studies designed to investigate the specific contribution of genetic factors to the outcome after invasive coronary interventions.

5A/6A polymorphism of the stromelysin-1 gene and angiographic restenosis after coronary artery stenting

BACKGROUND

Coronary stent deployment is a major advance in interventional treatment, but 20-40% of patients still develop in-stent restenosis (ISR) due to neointimal hyperplasia. Genetic factors play a role in restenosis. This study investigated the frequency of 5A/6A polymorphism in the promoter of the stromelysin-1 gene, and the issue of whether it contributes to restenosis among patients receiving coronary stent in the Chinese population in Taiwan.

METHODS

We investigated 344 symptomatic patients after successful coronary stent placement. All patients received repeated angiography after 6 months, or earlier if clinically indicated. Angiographic restenosis was defined as > or = 50% diameter stenosis at follow-up. Genotyping for stromelysin-1 promoter was based on a polymerase chain reaction technique.

RESULTS

The stromelysin-1 gene promoter genotypes 5A5A, 5A6A, and 6A6A were distributed in 3.5%, 22.7%, and 73.8% of patients, respectively. The frequency of the 6A allele was 0.85. There was no significant difference in angiographic ISR between the non-6A6A and 6A6A groups (28.9% and 37.0%, respectively, p = 0.165). However, subgroup analysis revealed a significant difference in patients according to angina status. Among the 5A5A and 5A6A genotype groups, patients with unstable angina had significantly higher ISR rates than those with stable angina (48% vs 21.5%, p = 0.013). On the other hand, among patients with stable angina, those with a 6A6A genotype had a higher ISR rate than those with a non-6A6A genotype (p = 0.029), making the 6A6A genotype an independent predictor of ISR (odds ratio, 2.57; 95% confidence interval, 1.22-5.41; p = 0.013).

CONCLUSION

There is a low frequency of the stromelysin-1 promoter 5A allele in the Chinese population in Taiwan. How stromelysin-1 5A/6A polymorphism affects ISR appears to be linked to angina status. These results merit further study to identify patients carrying genotypes which put them at increased risk of ISR, and which matrix metalloproteinase inhibitors or drug-eluting stents are more effective for those at risk.

Stromelysin-1 promoter 5A/6A polymorphism is an independent genetic prognostic risk factor and interacts with smoking cessation after index premature myocardial infarction

OBJECTIVE

To evaluate the prognostic roles of multiple polymorphisms and smoking cessation for premature myocardial infarction (MI).

METHODS

We studied 170 patients with MI onset before the age of 45 years (range 27-45 years, 84% men) and analyzed the traditional risk factors and several candidate genes' associations with their subsequent coronary events.

RESULTS

Follow-up data were available for a total of 162 individuals (95.3%) with the other 38 individuals (4.7%) being lost-to-follow-up premature MI patients. During a mean period of 4.43 years' follow-up, diabetes mellitus (DM), hypertension, hypercholesterolemia and Killip's status > or =II were more frequent among patients with subsequent cardiac events (all P-values <0.05). The frequency of 5A allele of stromelysin-1 gene was significantly higher among event group (P = 0.01). Smoking cessation after MI, use of beta-blocker or angiotensin-converting enzyme inhibitor (ACEI) could improve outcome (all P-values <0.05). After multivariate analysis, we found that DM was an independent risk factor for survival [Hazard ratio (HR) 2.45, P = 0.01]. Successful smoking cessation and therapy with ACEI could have a protective effect (HR 0.33 and 0.09, P = 0.01 and <0.01, respectively). The stromelysin-1 5A gene polymorphism was also an independent survival predictor (HR 2.51, P = 0.03). In addition, smoking cessation could significantly modify the risk, especially among patients with 5A allele polymorphism (HR 6.75 vs. 1.50).

CONCLUSION

We thus conclude that the stromelysin-1 gene polymorphism alone or in combination with smoking cessation can influence the prognosis after index premature MI.

Polymorphism of matrix metalloproteinase-3 promoter gene as a risk factor for coronary artery lesions in Kawasaki disease

Kawasaki disease (KD) is a major cause of acquired coronary artery diseases in childhood. The serum levels of matrix metalloproteinase (MMP)-3 and MMP-9 in KD have been reported to be significantly higher than other diseases. Several studies have demonstrated that MMP-3 5A/6A polymorphism and MMP-9 C-1562T polymorphism modify each transcriptional activity in allele specific manner. We hypothesized that these polymorphisms may play a role as a risk factor for development of coronary artery lesions (CAL) in KD. Eighty-three patients, diagnosed with KD in Cheju National University Hospital from January 2000 to February 2004, were divided into two groups according to the presence of CAL. Genotyping of MMP-3 and MMP-9 gene polymorphisms were determined by restriction fragment length polymorphism. With regard to MMP-3 gene polymorphism, the KD with CAL group had a higher frequency of 6A/6A genotype than control group (p=0.0127) and the KD without CAL group (p=0.0036). However, no significant differences in the allele and genotype distributions of the MMP-9 polymorphism were observed. These findings suggest that MMP-3 6A/6A genotype may be an independent risk factor for CAL formation in KD.

Vascular Access in Hemodialysis: Issues, Management, and Emerging Concepts

This article (1) identifies the types of hemodialysis access, (2) summarizes the clinical standard of care for dialysis access grafts and fistulae, (3) describes the pathology and pathogenesis of venous stenosis in dialysis access grafts and fistulae, (4) tabulates avail-able therapies for hemodialysis vascular access dysfunction and speculates on the rea-sons for the lack of effective therapies, and (5) discusses the development and application of novel therapeutic interventions for this difficult clinical problem. The possibility that dialysis access grafts and fistulae could be the ideal clinical model for testing novel local therapies to block neointimal hyperplasia is discussed.

Stromelysin-1 (MMP-3) gene 5A/6A promoter polymorphism is associated with blood pressure in a community population

BACKGROUND AND OBJECTIVES

Arterial remodelling contributes to the development of hypertension. Stromelysin-1 (MMP-3), a member of the matrix metalloproteinase family may contribute to this process. Stromelysin-1 gene expression is partly regulated by a common polymorphism in the promoter region of either five or six consecutive adenosine bases (5A/6A).

METHODS AND RESULTS

A cross-sectional study of 1111 randomly selected male and female community subjects (27-77 years), were assessed for conventional cardiovascular risk factors and stromelysin-1 5A-1171-6A genotype. Multivariate analysis showed an independent association between the stromelysin-1 genotype and blood pressure that was recessive for the 5A/5A genotype. Subjects with the 5A/5A genotype had a higher mean systolic blood pressure (SBP) (+4.2 mmHg) and diastolic blood pressure (DBP) (+2.2 mmHg) compared to subjects with 5A/6A and 6A/6A genotypes. Subgroup analysis revealed an independent association of the 5A/5A genotype with SBP (+3.6 mmHg, P = 0.001) and DBP (+2.0 mmHg, P = 0.004) in subjects not on blood pressure medication. Whereas subjects with the 5A/5A genotype and taking medication had a higher mean SBP (+7.4 mmHg, P = 0.02) and DBP (+2.7 mmHg, P = 0.11). Multivariate analysis in the whole population showed there was no association between genotypes and mean intimal-medial wall thickness (IMT) (P = 0.87) or the likelihood of carotid plaque formation.

CONCLUSIONS

The stromelysin-1 5A-1171-6A genotype is an important determinant of blood pressure in this general population sample.

The function of the SNP in the MMP1 and MMP3 promoter in susceptibility to endometriosis in China

Matrix metalloproteinases (MMPs) may contribute to the development of endometriosis. Genetic variations in several MMP promoters may influence the transcription and expression of MMPs. The purpose of the present study was to assess how gene polymorphisms in the MMP1 and MMP3 promoters affect the risk of development of endometriosis. We genotyped 100 women with endometriosis and 150 control subjects in North China. There was a significant difference in frequency of the MMP1 genotype between cases and controls (P=0.03). The 2G homozygote in endometriosis and controls was significantly different (P=0.02). The frequency of the 2G allele among affected women (79%) was significantly higher than among the healthy controls (66.9%; P=0.003). However, the overall genotype and allelotype distribution of the MMP3 single nucleotide polymorphism (SNP) in patients was not different from that of controls (P> or =0.05). MMP1 and MMP3 polymorphisms were in linkage disequilibrium in cases and controls (D'=0.47; P=0.00). The haplotype frequency distribution derived from these two polymorphisms was significantly different between cases and controls (P=0.00). The haplotype analysis suggested an implication of both MMP1 and MMP3 polymorphisms in the susceptibility to endometriosis. We conclude that the MMP1 promoter SNP and MMP 2G/6A haplotype may modify susceptibility to endometriosis, but that the MMP3 promoter SNP is unlikely to be associated with endometriosis in the population of North China.

Positive selection on MMP3 regulation has shaped heart disease risk

BACKGROUND

The evolutionary forces of mutation, natural selection, and genetic drift shape the pattern of phenotypic variation in nature, but the roles of these forces in defining the distributions of particular traits have been hard to disentangle. To better understand the mechanisms contributing to common variation in humans, we investigated the evolutionary history of a functional polymorphism in the upstream regulatory region of the MMP3 gene. This single base pair insertion/deletion variant, which results in a run of either 5 or 6 thymidines 1608 bp from the transcription start site, alters transcription factor binding and influences levels of MMP3 mRNA and protein. The polymorphism contributes to variation in arterial traits and to the risk of coronary heart disease and its progression.

RESULTS

Phylogenetic and population genetic analysis of primate sequences indicate that the binding site region is rapidly evolving and has been a hot spot for mutation for tens of millions of years. We also find evidence for the action of positive selection, beginning approximately 24,000 years ago, increasing the frequency of the high-expression allele in Europe but not elsewhere. Positive selection is evident in statistical tests of differentiation among populations and haplotype diversity within populations. Europeans have greater arterial elasticity and suffer dramatically fewer coronary heart disease events than they would have had this selection not occurred.

CONCLUSIONS

Locally elevated mutation rates and strong positive selection on a cis-regulatory variant have shaped contemporary phenotypic variation and public health.

Genetic risk for restenosis after coronary balloon angioplasty

Plain old balloon angioplasty (POBA) is a useful therapeutic strategy especially for angioplasty of small coronary arteries. An association study was performed to identify genes that confer susceptibility to restenosis after POBA. The study population comprised 730 individuals (424 men, 306 women) who underwent successful POBA in at least one major coronary artery and were examined angiographically 6 months after the procedure. A total of 469 subjects (273 men, 196 women) exhibited no restenosis after POBA for any of the coronary lesions, whereas 261 subjects (151 men, 110 women) manifested restenosis for all lesions. The genotypes for 40 polymorphisms of 34 genes were determined with a fluorescence- or colorimetry-based allele-specific DNA primer-probe assay. Multivariate logistic regression analysis with adjustment for age, body mass index, and the prevalence of smoking, hypertension, diabetes mellitus, hypercholesterolemia, and hyperuricemia revealed that two polymorphisms (242C --> T in the NADH/NADPH oxidase p22 phox (p22-PHOX) gene and 2136C --> T in the thrombomodulin (THBD) gene) in men and two polymorphisms (584G --> A in the paraoxonase 1 (PON1) gene and 2445G --> A in the fatty acid-binding protein 2 (FABP2) gene) in women were significantly associated with restenosis after POBA. A stepwise forward selection procedure revealed that the effects of these polymorphisms on restenosis were statistically independent of conventional risk factors for coronary artery disease. Genotyping of these polymorphisms may prove informative for assessment of genetic risk for restenosis after POBA.

Matrix metalloproteinase-1 and -3 gene promoter polymorphisms in Japanese patients with periodontitis

BACKGROUND/AIMS

Matrix metalloproteinase (MMP)-1 and MMP-3 have important roles in the connective tissue remodelling and destruction processes in periodontitis. MMP-1 1G/2G (-1607) and MMP-3 5A/6A (-1171) polymorphisms have been identified and appear to influence the transcription of the genes. The aim of this study was to investigate whether these gene promoter polymorphisms were associated with the susceptibility to periodontitis.

MATERIAL AND METHODS

Genomic DNA was obtained from 37 generalised aggressive, 205 slight-to-severe generalised chronic-periodontitis patients and 142 healthy subjects. All subjects were non-smoking Japanese. We genotyped by using TaqMan PCR assay. The statistics were analysed by chi2-test.

RESULTS

We found no significant differences in genotype distributions, allele frequencies, carriage rates and haplotype frequencies in the MMP-1 and the MMP-3 gene promoter polymorphisms among all groups. The distributions of MMP-1 and MMP-3 genotypes in our study were different from those of previously reported in Caucasians or Brazilians, but consistent with previously reported in Japanese.

CONCLUSION

Our data did not support the hypothesis that MMP-1 and/or MMP-3 gene promoter polymorphisms influenced the susceptibility to periodontitis in Japanese patients, indicating MMP-1 and MMP-3 expressions were regulated by complex processes such as cytokine network in periodontal disease rather than gene polymorphisms.

Genetic predictive factors in restenosis

Restenosis is still the main drawback of percutaneous transluminal coronary angioplasty (PTCA). It is thought to be a multifactorial process where recoil of the vessel, neointimal proliferation and thrombus formation are thought to play a role. Until now it has proven difficult to predict restenosis on clinical and procedural grounds, however, genetic epidemiology might provide more insights. In this review several genetic variables, i.e. polymorphisms that were determined in relation to restenosis are described. The single nucleotide polymorphisms (SNPs) described in the literature so far involve; the renin-angiotensin system, platelet aggregation, the inflammatory response, matrix metalloproteinases, smooth muscle cell proliferation, lipids and oxidative stress and nitric oxide. Nowadays DNA-microarrays have been developed which make it possible to test 50 or 60 polymorphisms at once. However, the risk of error due to multiple testing should be kept in mind. The results of the studies described should be interpreted with care. Many of the published studies are of relatively small sample size, which sometimes show more positive outcomes than the larger studies, this is possibly due to publication bias towards more positive results. The small sample size studies also exhibit wide confidence intervals. On the other hand, one must take into account that the process of restenosis is a multifactorial one and it is likely that multiple genes are involved. Thus, relatively small odds ratios relating to single gene contribution to restenosis can be of paramount importance when encompassed in the overall picture. Although still much research has to be done, stratification according to genetic make-up may enable tailoring of the interventional treatment to the individual patient.

NF-kappaB binds to a polymorphic repressor element in the MMP-3 promoter

A 5T/6T polymorphic site in the matrix metalloproteinase-3 (MMP-3) promoter has been identified as a repressor element involved in inhibiting induction of MMP-3 transcription by interleukin 1; and the 6T allele has been associated with decreased expression of MMP-3 as compared to the 5T allele. Zinc-binding protein-89 (ZBP-89) was cloned from a yeast one-hybrid assay via its ability to interact with this site, but when the protein was over-expressed, it resulted in activation of the MMP-3 promoter rather than repression. Here we show that in nuclear extracts isolated from human gingival fibroblasts stimulated with IL-1, this site is bound by p50 and p65 components of NF-kappaB in addition to ZBP-89, and that recombinant p50 binds preferentially to the 6T binding site. These results are consistent with a role for NF-kappaB in limiting the cytokine induced expression of MMP-3.

Thalidomide as a potent inhibitor of neointimal hyperplasia after balloon injury in rat carotid artery

OBJECTIVE

Inflammation is one of the main pathogeneses of neointimal hyperplasia after coronary intervention. Thalidomide, because of its potent antiinflammatory and immunomodulatory properties, is being re-evaluated in several clinical fields. Therefore, we examined whether thalidomide therapy affects neointimal formation.

METHODS AND RESULTS

In male Sprague-Dawley rats, 100 mg/kg of either thalidomide or sucrose (control) was administered daily from 3 days before injury to 2 weeks after conventional carotid artery denudation injury. Thalidomide administration resulted in a significant reduction of neointimal formation (neointima to media ratio 1.26+/-0.29 versus 0.35+/-0.13, P<0.001) and proliferative activity of vascular smooth muscle cells. In addition, arterial macrophage infiltration and local expressions of tumor necrosis factor alpha (TNF-alpha) and basic fibroblast growth factor (bFGF) in the injured arteries as measured by immunohistochemistry and immunoblot analysis were significantly reduced by thalidomide treatment. Serum TNF-alpha, measured by ELISA, was also significantly reduced in the thalidomide-treated animals compared with controls after injury (856+/-213 versus 449+/-68 pg/mL on day 3, P=0.001; 129+/-34 versus 63+/-18 pg/mL on day 14, P=0.001), and we observed a good positive correlation between the serum TNF-alpha levels and the severity of neointimal growth.

CONCLUSIONS

We found that thalidomide, through its antiinflammatory and antiproliferative effects, significantly inhibits neointimal hyperplasia in balloon-injured rat carotid arteries. Our results suggest a potential role of thalidomide as a potent inhibitor of neointimal formation after angioplasty.

Genetic determinants of arterial calcification associated with atherosclerosis

Increasing research interest has focused on arterial calcification in the setting of atherosclerosis. Many features of atherosclerosis-related calcification provide useful clinical information. For example, calcium mineral deposits frequently form in atherosclerotic plaque, and intimal arterial calcification can be used as a surrogate marker for atherosclerosis; also, calcium deposits are readily and noninvasively quantified, which is useful because greater amounts of coronary calcification predict a higher risk of myocardial infarction and death. Several mechanisms leading to calcification associated with atherosclerosis have been proposed; however, no direct testing of proposed mechanisms has yet been reported. Studies in genetically altered animals and in humans have shed light on potential genetic determinants, which in turn could form the basis for a more comprehensive understanding of the factors affecting calcification within plaque and the associated pathobiologic implications. We review proposed molecular and cellular mechanisms of atherosclerosis-associated arterial calcification, summarize genetic influences, and suggest areas in which further investigation is needed. Understanding the molecular and genetic determinants of specific structural plaque components such as calcification can provide a solid foundation for the development of novel therapeutic approaches to favorably alter plaque structure and minimize vulnerability to arterial rupture.

Polymorphisms in the promoter regions of MMP-2, MMP-3, MMP-9 and MMP-12 genes as determinants of aneurysmal coronary artery disease

OBJECTIVES

Our hypothesis was that functional polymorphisms in matrix metalloproteinase (MMP) genes may act as susceptibility factors for the development of coronary aneurysms (CAs).

BACKGROUND

Different forms of remodeling have been described at the level of coronary arteries; CA, reported in 1% to 5% of patients with angiographic evidence of coronary artery disease (CAD), are one of them. Matrix metalloproteinases have been implicated in the pathogenesis of aneurysm development through increased proteolysis of extracellular matrix proteins.

METHODS

We screened 3,862 patients who underwent coronary angiography and identified 113 patients with CAD with at least one CA (CA group); these patients were matched with 226 patients with CAD without CA (control group). The -1,306 C/T MMP-2, 5A/6A MMP-3, CA-repeat MMP-9 and -82 A/G MMP-12 polymorphisms were determined.

RESULTS

The MMP-2, MMP-9 and MMP-12 polymorphisms were not associated with CA. By contrast, the 5A/5A genotype of MMP-3 was significantly more frequent in the CA group than in the control group (31% vs. 18%, p = 0.015); similarly, the MMP-3 5A allele was more frequent in the CA group (p = 0.009). Three variables were independently associated with CA: the MMP-3 5A/5A genotype (odds ratio [OR] = 2.23, 95% confidence interval [CI] [1.27 to 3.93]), a previous myocardial infarction (OR = 1.91, 95% CI [1.14 to 3.20]) and a history of aortic aneurysm (OR = 21.06, 95% CI [2.35 to 188]).

CONCLUSIONS

The MMP-3 5A allele is associated with the occurrence of CA. Our results suggest that an increased proteolysis in the arterial wall may act as a susceptibility factor for the development of CA in patients with coronary atherosclerosis.