Association of Endothelial Nitric Oxide Synthase Gene Variant (G894T) With Coronary Artery Disease in Western Iran

Association of Endothelial Nitric Oxide Synthase Gene Polymorphisms with Coronary Artery Disease in North Indian Punjabi Population

Nitric oxide (NO) a potent vasodilator synthesized by endothelial cells has anti-atherosclerotic properties and maintains vascular tone. It has been documented that its reduced bioavailability in vascular endothelium plays an important role in the development and progression of coronary artery disease (CAD). Therefore, we aimed to investigate the association of - 786 T > C and 894 G > T polymorphisms of eNOS with CAD. This study included 211 CAD patients and 260 controls of North Indian Punjabi population. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Logistic regression analysis revealed that the TC and CC genotypes of - 786 T > C were significantly associated with the higher risk of CAD (OR: 2.00, p = 0.001: OR: 4.63, p = 0.001, respectively). Similarly, the GT and TT genotypes of 894 G > T were found to be significantly associated with the higher risk of CAD (OR: 1.96, p = 0.001; OR: 4.54, p = 0.005, respectively). Moreover, the recessive model in  - 786 T > C (OR: 3.58, p = 0.002) and 894 G > T (OR: 3.62, p = 0.009) polymorphisms provided 3.6-fold increased risk for CAD. Furthermore, the CG, TT, and CT haplotypes were also associated with the increased risk of CAD (OR: 2.1, p = 0.001; OR: 2, p = 0.002; OR: 3.1, p = 0.001, respectively). In addition, the CC genotype of - 786 T > C and GT genotype of 894 G > T were significantly associated with higher levels of triglycerides (TG) and very low-density lipoproteins cholesterol (VLDL-C). The present study reported the association of - 786 T > C and 894 G > T polymorphisms of eNOS with CAD and abnormal lipid levels in North Indian Punjabi population.

Frequency of Cardiac Arrhythmias in Children with Cardiological Consulting and Containing Electrocardiogram

BACKGROUND

Heart diseases are the leading causes of mortality and congenital heart disease (CHD) is the most common birth defect reported worldwide.

OBJECTIVE

The aim of this study was to evaluate the incidence of arrhythmias and CHD and the association between the two, among infants and children reported to our center.

METHODS

This cross-sectional study included infants and children who were referred to Shahid Madani Hospital, Khorramabad. Electrocardiogram (ECG) was performed in these children to determine the type of arrhythmia and records were used to obtain demographic data and the data regarding CHD.

RESULTS

Of 200 children enrolled in the study, 10 children had arrhythmias, 12 had tachycardia, 5 had bradycardia, and 31 had congenital disease. Among children with arrhythmias, 1 had atrial fibrillation, 4 patients had paroxysmal supraventricular tachycardia, 1 person had right bundle branch block, 1 had ventricular tachycardia, 2 had premature ventricular contractions and 1 had junctional ectopic tachycardia. Of the 31 children with CHD, 9 patients were presented with small ventricular septal defect, 4 children had patent foramen ovale, 2 had pulmonary stenosis and 1 of the children had tetralogy of fallout, arterial and ventricular septal defects and transposition of greater arteries, respectively.

CONCLUSION

We reported a positive correlation between the arrhythmias and CHD. A larger number of studies collecting focusing on different age groups are therefore required to verify our findings.

Dietary inorganic nitrate attenuates hyperoxia-induced oxidative stress in obese type 2 diabetic male rats

AIMS

Hyperoxia has beneficial metabolic effects in type 2 diabetes. However, hyperoxia exacerbates already existing oxidative stress in type 2 diabetes. Nitrate, a nitric oxide donor, is an effective new treatment in type 2 diabetes and also has antioxidant properties. The aim of this study was to determine whether nitrate administration can attenuate hyperoxia-induced oxidative stress in obese type 2 diabetic rats.

MAIN METHODS

Fifty-six male Wistar rats (190-210 g) were divided into 8 groups: Controls (non-treated, nitrate-treated, O₂-treated, and nitrate + O₂-treated) and diabetes (non-treated, nitrate-treated, O₂-treated, and nitrate + O₂-treated). Diabetes was induced using high-fat diet and low-dose of streptozotocin (30 mg/kg). Rats in intervention groups, were exposed to 95% oxygen and consumed sodium nitrate (100 mg/L) in drinking water. Serum fasting glucose, oxidized (GSSG) and reduced (GSH) glutathiones, total oxidant status (TOS), catalase and superoxide dismutase (SOD) activities, and total antioxidant capacity (TAC) were measured after intervention. Oxidative stress index (OSI) was calculated as TOS/TAC ratio.

KEY FINDINGS

Diabetic rats had increased oxidative stress and hyperoxia exacerbated it. In O₂-diabetic rats, nitrate decreased GSSG (102.7 ± 2.1 vs. 236.0 ± 20.1 μM, P < 0.001), TOS (67.7 ± 7.3 vs. 104 ± 3.8 μM, P < 0.001), and OSI (0.44 ± 0.04 vs. 0.91 ± 0.07, P < 0.001) and increased catalase (2.8 ± 0.13 vs. 1.8 ± 0.21 KU/L, P = 0.014), SOD (53.4 ± 1.5 vs. 38.4 ± 1.2 U/mL, P < 0.001), GSH (43.7 ± 1.4 vs. 17.8 ± 0.5 mM, P = 0.003), TAC (152.5 ± 1.9 vs. 116.7 ± 5.0 mM, P < 0.001), and GSH/GSSG ratio (0.43 ± 0.01 vs. 0.08 ± 0.01, P = 0.005). Nitrate also potentiated effects of hyperoxia on decreasing fasting glucose.

SIGNIFICANCE

Our results showed that dietary nitrate attenuates hyperoxia-induced oxidative stress in type 2 diabetic rats.

Endothelial nitric oxide synthase Glu 298 Asp (G894T) and Apolipoprotein E gene polymorphism as possible risk factors for coronary heart disease among Egyptians

In Egypt, The prevalence of chronic heart disease (CHD) is 8.3%. It is the principal cause of death and is responsible for 22% of total mortality. The age-adjusted mortality rate is 174 per 100,000 of population. There are many studies on traditional risk factors and CHD in Egypt but the study of novel risk factors is deficient.

Objectives

The aim of the present case control study was to investigate the relation between CHD susceptibility and Endothelial Nitric Oxide Synthase (eNOS) Glu 298 Asp (G894T) and Apolipoprotein E (ApoE) gene polymorphism in a cohort of Egyptian individuals.

Methods

Genotyping of eNOS (Glu298Asp) and Apo E genes polymorphisms were done using polymerase chain reaction-restriction fragment length polymorphism (PCR–RFLP) method for 100 CHD cases and 100 age and sex matched healthy controls.

Results

A statistically significant association was observed between GT and TT genotypes of endothelial nitric oxide synthase gene with CHD with OR = 2.03 and 3.5; respectively. Also, carriers of E4 allele and especially E3/E4 genotype were at higher risk of CHD with OR = 3.3 for both. Significant association was also observed between the presence of combined GTE3E4 genotype and CHD with OR = 6.6.

Conclusion

GT and TT genotypes of endothelial nitric oxide synthase gene, E3/E4 genotype of Apo E gene polymorphism and combined GTE3E4 genotype can be considered risk factors for the development of CHD among Egyptians.

Association of endothelial nitric oxide synthase gene polymorphisms with coronary artery disease: an updated meta-analysis and systematic review

Several association studies of endothelial nitric oxide synthase (NOS3) gene polymorphisms with respect to coronary artery disease (CAD) have been published in the past two decades. However, their association with the disease, especially among different ethnic subgroups, still remains controversial. This prompted us to conduct a systematic review and an updated structured meta-analysis, which is the largest so far (89 articles, 132 separate studies, and a sample size of 69,235), examining association of three polymorphic forms of the NOS3 gene (i.e. Glu298Asp, T786-C and 27bp VNTR b/a) with CAD. In a subgroup analysis, we tested their association separately among published studies originating predominantly from European, Middle Eastern, Asian, Asian-Indian and African ancestries. The pooled analysis confirmed the association of all the three selected SNP with CAD in three different genetic models transcending all ancestries worldwide. The Glu298Asp polymorphism showed strongest association (OR range = 1.28–1.52, and P<0.00001 for all comparisons), followed by T786-C (OR range = 1.34–1.42, and P<0.00001 for all comparisons) and 4b/a, (OR range = 1.19–1.41, and P≤0.002 for all comparisons) in our pooled analysis. Subgroup analysis revealed that Glu298Asp (OR range = 1.54–1.87, and P<0.004 for all comparisons) and 4b/a (OR range = 1.71–3.02, and P<0.00001 for all comparisons) have highest degree of association amongst the Middle Easterners. On the other hand, T786-C and its minor allele seem to carry a highest risk for CAD among subjects of Asian ancestry (OR range = 1.61–1.90, and P≤0.01 for all comparisons).

Analysis of endothelial nitric oxide synthase (eNOS) G894T polymorphism and semen parameters in a Chinese Han population

Previous studies have shown that endothelial nitric oxide synthase (eNOS) gene may be involved in abnormal semen parameters. However, the relationship between eNOS G894T polymorphism and semen parameters remains controversial. The purpose of this study was to investigate the association of eNOS G894T polymorphism and semen parameters. The genotype frequency of eNOS G894T was determined in 270 idiopathic asthenozoospermia patients and 248 ethnically matched healthy volunteers using iPLEX genotyping assays on a MassARRAY(®) (Sequenom, San Diego, CA, USA) platform. The statistical analysis performed with Fisher's exact test showed no significant difference in frequencies of genotypes between both groups. The logistic regression showed that genotypes GT, TT and allele T were nonassociated with increased risk of asthenozoospermia in the patient group with ≤5% or >5% sperm with normal forms. The dependence on genotypes of semen parameters was further investigated in both patients and control group. There was no significant difference as compared to control group (P > 0.05). Our study indicated that eNOS gene G894T polymorphism may not have an adverse effect on semen parameters in a Chinese Han population.

Association between the endothelial nitric oxide synthase gene Glu298Asp polymorphism and coronary heart disease: a meta‑analysis of 39 case‑control studies

Numerous studies have indicated that the human endothelial nitric oxide synthase (eNOS) gene Glu298Asp polymorphism is associated with coronary heart disease (CHD) susceptibility, however, their conclusions are inconsistent. The present meta‑analysis aimed to evaluate the precise result by searching the PubMed database and using 39 case‑control studies comprising 7489 cases and 7051 controls.Each study tested the association between the eNOS Glu298Asp polymorphism and CHD. A meta‑analysis was then conducted using the Comprehensive Meta Analysis 2.2 software to calculate the pooled odds ratios (ORs) of five genetic models with 95% confidence intervals (CIs). Publication bias was also explored. The meta‑analysis showed a significant association between the eNOS Glu298Asp polymorphism and CHD susceptibility for all the genetic models [Asp vs. Glu, OR 1.26, 95% CI 1.14‑1.40, P<0.001; Asp/Asp vs. Glu/Glu, OR 1.58, 95% CI 1.23‑2.02, P<0.001; Glu/Asp vs. Glu/Glu, OR 1.12, 95% CI 1.03‑1.22, P=0.001; (Glu/Asp+Asp/Asp) vs. Glu/Glu, OR 1.17, 95% CI 1.07‑1.27, P<0.001; Asp/Asp vs. (Glu/Glu+Glu/Asp), OR 1.59, 95% CI 1.25‑2.03, P<0.001]. Subgroup and sensitivity analyses indicated that the result was robust. A weak publication bias was detected. The results indicated that the eNOS Glu298Asp polymorphism is a risk factor for developing CHD, particularly in the Asian population.

Strong interaction between T allele of endothelial nitric oxide synthase with B1 allele of cholesteryl ester transfer protein TaqIB highly elevates the risk of coronary artery disease and type 2 diabetes mellitus

Background

The present study was conducted to investigate the possible outcome of interaction between endothelial nitric oxide (NOS3) G894T and cholesteryl ester transfer TaqIB variants on the risk of coronary artery disease (CAD) and type 2 diabetes mellitus (T2DM). The sample included a total of 207 CAD patients (102 CAD patients with T2DM and 105 CAD patients without T2DM). There were also 101 patients with T2DM and 92 age- and sex-matched healthy individuals as controls. All study participants were from Western Iran. The sample was genotyped by polymerase chain reaction-restriction fragment length polymorphism.

Results

The presence of NOS3 T allele was not associated with the risk of CAD or T2DM, and the CETP B1 allele was only significantly associated with the increased risk of CAD in total CAD patients (odds ratio (OR) = 5.1, p = 0.019). However, the concomitant presence of both CETP B1 and NOS3 T alleles significantly increased the risk of CAD in total CAD patients (OR = 18.1, p < 0.001), in CAD patients without T2DM (OR = 27.1, p = 0.03), and in CAD patients with T2DM (OR = 13.5, p = 0.002). Also, the presence of both alleles increased the risk of T2DM (OR = 12, p = 0.004).

Conclusions

Our findings, for the first time, indicate that NOS3 T allele strongly interacts with CETP B1 allele to augment the risk of CAD and T2DM in the population of Western Iran.

The G894T polymorphism on endothelial nitric oxide synthase gene is associated with increased coronary heart disease among Asia population: evidence from a Meta analysis

INTRODUCTION

Growing studies have revealed the underlying association between eNOS 894G/T (rs1799983) polymorphism and coronary heart disease (CHD) among Asia population. Results from these studies remained conflicting. We conducted this meta-analysis to estimate the overall CHD risk of eNOS 894G/T polymorphism regarding Asia population.

MATERIALS AND METHODS

Up to October 2011, databases including PubMed, Embase and CNKI (China National Knowledge Infrastructure) were searched to access the relevant genetic association studies. Summary odds ratios and corresponding 95% confidence intervals (CIs) for eNOS 894G/T polymorphism and CHD risk were estimated using fixed or random-effects models when appropriate.

RESULTS

18 case-control studies with 2,994 cases and 3,130 controls were available for this study, including 13 studies of East-Asia descendents, 5 studies of Non East-Asian descendents. The mean T allele frequency was 0.111 in the East-Asia population and 0.147 in the Non East-Asia population, respectively. The summary OR for CHD associated with the T allele was 1.52 (95% confidence intervals (95%CI), 1.37-1.69) by random effects model. Similarly, significantly increased risks were observed in the East-Asia population (OR=1.54; 95%CI=1.35-1.76) and in the Non East-Asia population (OR=1.48; 95%CI=1.24-1.77), respectively.

CONCLUSIONS

This meta-analysis indicated that eNOS 894G/T polymorphism may play an important role in CHD development among Asia population.