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

Relationship between the AGT M235T genetic variant and the characteristics and prognosis of coronary atherosclerosis in patients with acute myocardial infarction

BACKGROUND

Along with environmental components, genetic factors play an essential role in the pathophysiology and progression of acute myocardial infarction (AMI). There is limited and conflicting data on the influence of the AGT M235T genetic variant on coronary atherosclerosis and death in AMI patients.

METHODS

We carried out a prospective cohort study among 504 Vietnamese AMI patients selected between January 2020 and May 2021. All patients underwent invasive coronary angiography, had AGT M235T genetic variant genotyped using the polymerase chain reaction method, and were followed up for 12-month all-cause mortality.

RESULTS

The proportions of the MM, MT, and TT genotypes were 0.4%, 20.8%, and 78.8%, respectively. There was no significant difference between the TT genotype and the MM + MT genotype groups regarding the position and number of stenosed coronary artery branches and the Gensini score. The AGT M235T genetic variant did not affect 12-month mortality (hazard ratio of TT vs. MM + MT: 1.185; 95% confidence interval: 0.596-2.354; P = 0.629). Subgroup analyses by age, sex, hypertension, diabetes mellitus, dyslipidemia, obesity, smoking, and angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker therapy also did not reveal an association between the AGT M235T variant and all-cause mortality.

CONCLUSION

In summary, the AGT M235T genetic variant was not found to be associated with coronary atherosclerosis characteristics and 12-month mortality in Vietnamese patients with AMI. Further multicenter studies with larger sample sizes and extended follow-up periods are needed to investigate this issue.

Interaction between COX-2 G-765C and smoking in relation to coronary artery disease in a Chinese Uighur population

BACKGROUND

Coronary artery disease (CAD) is a complex multifactorial and polygenic disorder where multiple environmental and genetic factors are involved simultaneously. The purpose of this study was to explore the relationship between the interaction of cyclooxygenase-2 (COX-2) gene polymorphism and smoking and CAD in a Uighur population.

METHODS

Using a case-control study of Chinese Uighur CAD patients (n=430) and healthy controls (n=470), we investigated the roles of G-765C polymorphism in the COX-2 gene (PTGS2) by the use of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis.

RESULTS

The PTGS2 GG genotype was significantly more prevalent in CAD patients (84.6% vs. 78.3%; p=0.014). Multiple logistic regression analysis showed two independent risk factors: smoking (OR 1.89, 95% CI 1.01-5.24; p=0.008) and hypertension (OR 2.73, 95% CI 1.59-7.21; p=0.001). Moreover, there was a synergistic effect between smoking and the PTGS2 polymorphism and the occurrence of CAD (interaction p=0.009). The odds ratio (OR) estimated by the combined analysis of the PTGS2 GG genotype and smoking history (OR 4.09, 95% CI 2.7-9.3) was markedly higher than that estimated separately from the PTGS2 GG genotype (OR 1.28, 95% CI 0.8-1.9) or smoking (OR 2.51, 95% CI 1.5-5.7) alone. Plasma 6-keto-PGF1α, a stable metabolite of PGI(2), was lower in individuals with the PTGS2 GG genotype (p<0.05). Smoking could further lower plasma 6-keto-PGF1α concentrations in GG genotype carriers than non-smokers, especially in patients with CAD.

CONCLUSIONS

The PTGS2 polymorphism and smoking were synergistically and significantly associated in Chinese Uighur patients with CAD.

Association of Interaction Between Smoking and CYP 2C19*3 Polymorphism With Coronary Artery Disease in a Uighur Population

Objectives: Cytochrome P450 (CYP) 2C19 is expressed in vascular endothelium and metabolizes arachidonic acid to biologically active epoxyeicosatrienoic acids (EETs), which are potent endogenous vasodilators and inhibitors of vascular inflammation. The purpose of this study is to explore the relationship between the interaction of CYP2C19*3 polymorphism and smoking and coronary artery disease (CAD) in a Uighur population. Methods: In a Chinese Uighur case-control study of patients with CAD (n = 336) and healthy controls (n = 370), we investigated the roles of polymorphism in the CYP2C19 gene by the use of polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis. Results: The CYP2C19*3 AG + AA genotype was significantly more prevalent in patients with CAD (6.25.0% vs 2.96%; P = .03). Multiple logistic regression analysis showed 4 independent risk factors: the interaction of CYP2C19*3 and smoking (OR 7.22, 95% confidence interval [CI] 2.32-10.23; P = .009), smoking (OR 3.23, 95% CI 1.72-5.44; P = .003), blood sugar (OR 2.12, 95% CI 1.03-4.21; P < .01), and hypertension (OR 1.74, 95% CI 0.98-2.34; P = .013). Conclusions: The CYP2C19*3 polymorphism and CAD were synergistically and significantly associated in Chinese Uighur patients.

Smoking and atherosclerotic cardiovascular disease: Part IV: Genetic markers associated with smoking

Genes influence smoking behavior, affect the metabolism of nicotine and specific chemicals produced during combustion, and enhance (or diminish) pathomechanistic pathways associated with the atherogenic potential of smoking, including oxidative stress, its inflammatory burden or procoagulant potential. Genome-wide association studies have revolutionized the search for new functional genetic markers with ever increasing marker density and the precision in identifying new genetic loci without the need for prior knowledge of functional pathways. Nevertheless, the statistical challenge remains to identify the few true positives, the need for replication of findings and the tedious work of identifying functional genetic variants and their mode of action. Genetic variation within a gene or in areas of the genetic code that control the expression of such a gene is far from being understood. Major advances include the detection of large-scale copy-number variants in the human genome and the demonstration of the decisive role of ‘miRNA’ in controlling gene expression. The role of the genomic methylation pattern in controlling the transcription of the underlying genetic sequence and its role in interacting with environmental influences have yet to be explored in depth. Although candidate genes and their genetic variants have been associated with atherosclerosis and cigarette smoking, a major breakthrough has still to be made.

NF-kappaB and ZBP-89 regulate MMP-3 expression via a polymorphic site in the promoter

A 5T/6T polymorphism in the human MMP-3 promoter affects gene expression and impacts the risk and/or severity of various pathological conditions. Chromatin immunoprecipitation (ChIP) in human fibroblasts homozygous for the 6T site demonstrate that it is bound by NF-kappaB and ZBP-89 transcription factors in its native chromatin. ChIP in COS-1 cells transfected with plasmids containing the 5T and 6T sites in the context of 2kb of the MMP-3 promoter showed that NF-kappaB p50 binds preferentially to the 6T site, while more ZBP-89 binding is detected to the 5T site. Over-expressed ZBP-89 increased transcription from the 5T promoter but not from the 6T, while NF-kappaB decreased transcription from both promoters, even in the presence of excess ZBP-89. A model is suggested in which the physiological impact of the polymorphism is dependent on the relative levels and activities of these competing factors in various cell types and conditions.

Synergistic effect of cytochrome P450 epoxygenase CYP2J2*7 polymorphism with smoking on the onset of premature myocardial infarction

OBJECTIVES

Cytochrome P450 (CYP) 2J2 is expressed in vascular endothelium and metabolizes arachidonic acid to biologically active epoxyeicosatrienoic acids (EETs), which are potent endogenous vasodilators and inhibitors of vascular inflammation. We aimed to elucidate the relationship between the functional CYP2J2*7 polymorphism and smoking for the onset of premature myocardial infarction (MI).

PATIENTS/METHODS

We studied 200 patients with acute MI onset under 45 years (84% men) and 200 sex- and age-matched controls. The polymorphism was determined using PCR and direct DNA sequencing analysis.

RESULTS

The CYP2J2*7 GT+TT genotype was significantly more prevalent in premature MI patients (32.0% versus 22.0%; p=0.02). Multiple logistic regression analysis showed four independent risk factors: the CYP2J2*7 T allele (OR 1.78, 95% confidence interval [CI] 1.1-6.4; p=0.02), smoking (OR 3.05, 95% CI 1.6-7.3; p<0.01), diabetes mellitus (OR 3.24, 95% CI 1.2-6.6; p<0.01), and hypertension (OR 1.95, 95% CI 1.1-5.7; p<0.01). Among non-smoking patients, the CYP2J2*7 T allele was associated with a 1.3-fold risk. However, smoking T-allele carriers had a significantly 6.7-fold higher risk (p=0.01 for interaction). This variant, but not wild type, significantly reduced promoter activity with nicotine in vitro. EET metabolites were significantly lower among CYP2J2*7 T allele carriers than the GG subjects (p<0.05). Smoking could further lower EET concentrations in T allele carriers than the non-smokers, especially in MI patients (3.3+/-1.0 ng/mL versus 6.8+/-1.3 ng/mL; p=0.001).

CONCLUSIONS

The CYP2J2*7 polymorphism and premature MI were synergistically and significantly associated in Taiwanese patients.

Myocardial Matrix Remodeling and the Matrix Metalloproteinases: Influence on Cardiac Form and Function

It is now becoming apparent that dynamic changes occur within the interstitium that directly contribute to adverse myocardial remodeling following myocardial infarction (MI), with hypertensive heart disease and with intrinsic myocardial disease such as cardiomyopathy. Furthermore, a family of matrix proteases, the matrix metalloproteinases (MMPs) and the tissue inhibitors of MMPs (TIMPs), has been recognized to play an important role in matrix remodeling in these cardiac disease states. The purpose of this review is fivefold: 1) to examine and redefine the myocardial matrix as a critical and dynamic entity with respect to the remodeling process encountered with MI, hypertension, or cardiomyopathic disease; 2) present the remarkable progress that has been made with respect to MMP/TIMP biology and how it relates to myocardial matrix remodeling; 3) to evaluate critical translational/clinical studies that have provided a cause-effect relationship between alterations in MMP/TIMP regulation and myocardial matrix remodeling; 4) to provide a critical review and analysis of current diagnostic, prognostic, and pharmacological approaches that utilized our basic understanding of MMP/TIMPs in the context of cardiac disease; and 5) most importantly, to dispel the historical belief that the myocardial matrix is a passive structure and supplant this belief that the regulation of matrix protease pathways such as the MMPs and TIMPs will likely yield a new avenue of diagnostic and therapeutic strategies for myocardial remodeling and the progression to heart failure.