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.

基因芯片技术分析内皮型一氧化氮合酶基因多态性与冠心病的关系

目的探讨内皮型一氧化氮合酶（eNOS）Glu298Asp基冈多态性与冠心病的关系。方法以89例冠心病患者为病例组（男性62例,女性27例）,均行冠状动脉造影确诊,对照组78例（男性44例,女性34例）均行冠状动脉造影排除冠心病,运用基因芯片技术方法检测eNOS Glu298 Asp基因的多态性,对比分析冠心病组及对照组eNOS Glu298 Asp基因型及等位基因的差异。结果eNOS Glu298 Asp基因型分布冠心病组与对照组比较差异无统计学意义（P=0．495）,D等位基因频率冠心病组（10．11％）与对照组（10．27％）相比差异无统计学意义（P=0．965）。结论eNOS Glu298 Asp基因变异与冠心病的发病可能无相关性。     

The Glu298Asp polymorphism in endothelial nitric oxide synthase gene is associated with coronary in-stent restenosis

BACKGROUND: Reduced or impaired synthesis of nitric oxide promotes the proliferation of vascular smooth muscle cells, and thus may induce the neointimal formation leading to coronary in-stent restenosis. Recent reports have suggested that the Glu298Asp polymorphism in exon 7 of the endothelial nitric oxide synthase gene is associated with coronary spasm and acute myocardial infarction. In this study, we have examined the implication of this polymorphism with regard to coronary restenosis after Palmaz-Schatz stent deployment. METHODS: Eighty-nine lesions in 85 consecutive patients were treated with Palmaz-Schatz stents, and were prospectively followed up for 6 months. The lesions were classified into a restenosis group (% diameter stenosis=50%) and a non-restenosis group. Assessment was made using an automated quantitative angiographic system. We performed polymerase chain reaction-restriction fragment length polymorphism analysis to detect the missense Glu298Asp variant in exon 7 of the endothelial nitric oxide synthase gene. RESULTS: Coronary risk factors and angiographic findings of stenotic lesions did not differ between the groups. Univariate analyses showed that the missense Glu298Asp variant was the only statistically significant predictor of restenosis (odds ratio, 4.27; P=0.025). In addition, multiple logistic regression analysis revealed the missense Glu298Asp variant as the only independent predictor for in-stent restenosis (odds ratio, 3.90; P=0.036). CONCLUSIONS: The missense Glu298Asp variant may be an independent risk factor for in-stent restenosis.     

Endothelial nitric oxide synthase G894T (Glu298Asp) polymorphism was predictive of glycemic status in a 5-year prospective study of Chinese subjects with impaired glucose tolerance

Subjects with impaired glucose tolerance (IGT) have a high risk of developing type 2 diabetes mellitus (DM) and its related complications. However, both environmental and genetic factors may influence the progression or regression of hyperglycemia. Polymorphisms of the endothelial nitric oxide synthase (eNOS) gene have been associated with DM in cross-sectional studies, but their predictive values in glycemic progression are not known. We examined the relationship of the eNOS promoter -T786C (-T786C), intron 4 variable tandem repeat (in4a/b), and exon 7 G894T (G894T) polymorphisms, and their haplotypes, with the long-term glycemic outcome in a Chinese cohort with IGT. Two hundred fifty-six Chinese subjects with IGT at baseline participated in a 5-year follow-up study to assess their glycemic outcome. Each individual was genotyped for the above-mentioned polymorphisms. At 5 years, 40.2% of the subjects had reverted to normal glucose tolerance; 39.9% remained in IGT/impaired fasting glucose and 19.9% had developed DM. A significant gene effect of exon 7 G894T polymorphism on glycemic status at 5 years was demonstrated, with carriers of T(894) being more likely to have persistent hyperglycemia compared with GG subjects (P = .003). On stepwise logistic regression analysis, the presence of the T allele remained a significant risk factor for persistent hyperglycemia (odds ratio, 2.72; 95% confidence interval, 1.36-5.99; T+ vs GG; P = .013), together with male sex, high body mass index, and high 2-hour glucose at baseline. No significant effect of -T786C or in4a/b polymorphism on fifth-year glycemic status was observed. The eNOS G894T polymorphism appears to be predictive of persistent hyperglycemia in Chinese subjects with IGT.     

The Glu298Asp polymorphism in the endothelial nitric oxide synthase gene is strongly associated with coronary spasm

BACKGROUND: Coronary spasm seems to be associated with coronary nitric oxide deficiency. OBJECTIVES: We investigated whether the Glu298Asp polymorphism in the endothelial nitric oxide synthase (eNOS) gene is a definite risk factor for coronary spasm and whether diffuse spasm involving normal-looking coronary artery correlates significantly with the Glu298Asp polymorphism, in contrast with focal spasm superimposed on an atherosclerotic plaque. METHODS: A polymerase chain reaction followed by restriction fragment length polymorphism analysis was performed in 118 control participants and in 102 patients with variant angina and a similar degree of atherosclerotic burden. Patients with coronary spasm were divided into diffuse spasm and focal spasm subgroups according to morphological criteria. RESULTS: There was a significantly higher incidence of the Glu298Asp polymorphism in the coronary spasm group than in the control group (21.5% compared with 8.5%, P=0.006). Multiple logistic regression analysis using risk factors and the Glu298Asp polymorphism showed that the most important predictive factor for coronary spasm was the Glu298Asp polymorphism (odds ratio 2.83, 95% confidence interval 1.25-6.41, P=0.009). The diffuse spasm subgroup had a significantly higher frequency of the Glu298Asp polymorphism than the control group (25.9% compared with 8.5%, P=0.002). However, the focal spasm subgroup did not differ from the control group in the frequency of Glu298Asp polymorphism. CONCLUSION: The Glu298Asp polymorphism in the eNOS gene is a definite risk factor for coronary spasm, especially for diffuse coronary spasm. This result supports the notion that diffuse coronary spasm is significantly associated with endothelial dysfunction, in contrast to focal spasm.     

Association of endothelial nitric oxide synthase gene variant (G894T) with coronary artery disease in Western Iran

There are conflicting reports about the association of endothelial nitric oxide synthase (eNOS) gene polymorphism and the risk of coronary artery disease (CAD). To determine the frequency of eNOS G894T variant and to find the possible association between this polymorphism with CAD we studied 207 unrelated patients with total CAD (with and without diabetes) and 92 controls. The eNOS variants were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The presence of GT + TT genotype was associated with 2.1-fold (P = .006), 2.29-fold (P = .006), and 1.93-fold (P = .032) increased risk of CAD in total CAD, CAD with diabetes, and in CAD without diabetes patients, respectively. The presence of T allele of eNOS increased the risk of CAD 2.15-fold (P = .001). The levels of low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG) tended to be higher in patients carrier for T allele compared to those with G allele. The results of present study revealed that eNOS G894T polymorphism is associated with increased risk of CAD in our population.     

Endothelial nitric oxide synthase Glu298Asp gene polymorphism, blood pressure and hypertension in a general population sample

OBJECTIVE: The Glu298Asp (E/D) polymorphism of the endothelial nitric oxide synthase (eNOS) gene has been related to hypertension. Since several studies have produced contradictory results, this issue is still subject to ongoing debate. We investigated the association of the eNOS E298D polymorphism with hypertension and with blood pressure (BP) in a large population-based sample of Caucasian ethnicity. DESIGN: Cross-sectional study in a random sample of the general population. METHODS: The eNOS E298D polymorphism was determined by 5'-exonuclease assay among 4219 participants aged 20-79 years of the Study of Health in Pomerania (SHIP). RESULTS: The percentages of the EE298, ED298 and DD298 genotypes were 49.2, 42.0 and 8.8%, respectively. The D allele frequencies did not differ between the groups of normotensive and hypertensive subjects (29.7 versus 29.9%, P = 0.812). Similarly, no association could be established between E298D genotype and prevalent hypertension, neither for D allele carriership (multivariate odds ratio 0.97, 95% confidence interval 0.83-1.12) nor for DD homozygosity (multivariate odds ratio 1.10, 95% confidence interval 0.84-1.43). Likewise, genotype groups did not differ as to the distribution of systolic (ANCOVA P = 0.917) or diastolic BP values (ANCOVA P = 0.657). Nearly identical results were obtained if the analyses were repeated sex-specifically or if subjects on antihypertensive medication were excluded. CONCLUSION: In a population-based cohort of Caucasians covering a broad age range, the eNOS E298D polymorphism is neither associated with prevalent hypertension nor with systolic or diastolic BP. These results do not support the hypothesis that the E298D polymorphism contributes to the genetic susceptibility to hypertension.     

A missense mutation of the nitric oxide synthase (eNOS) gene (Glu298Asp) in five patients with coronary artery disease--case reports.

The authors report five patients with a missense mutation of the endothelial nitric oxide synthase (eNOS) gene (Glu298Asp) who have angiographically proven coronary artery disease (CAD). They compare their clinical findings and coronary arteriographic characteristics. They conclude that these case reports show that this mutation is not solely responsible for development of CAD. Diabetes mellitus, smoking, and hyperlipidemia are other risk factors.     

Endothelial nitric oxide synthase gene Glu298Asp polymorphism and blood pressure, left ventricular mass and carotid artery atherosclerosis in a population-based cohort

OBJECTIVE: Decreased production of endothelial nitric oxide (NO) is associated with different cardiovascular pathology. We studied the association between the Glu298Asp polymorphism of the NO producing gene, endothelial nitric oxide synthase (eNOS), and hypertension, left ventricular mass (LVM) and carotid artery intima-media thickness (IMT) in a population-based cohort of hypertensive and control subjects. DESIGN: Cross-sectional case-control study. SETTING: District around Oulu University Hospital, Northern Finland. SUBJECTS AND METHODS: The study population consisted of 600 middle-aged hypertensive subjects (300 men and 300 women) and 600 controls (300 men and 300 women) living in the City of Oulu. The hypertensive subjects were randomly selected by age stratification from the Social Insurance Institute register for reimbursement of antihypertensive medication. For each hypertensive subject, an age- and sex-matched control was randomly selected from the national health register. The overall participation rate was 87.8%. In the present study a total of 1024 subjects were screened. Echocardiographic examinations were performed by a trained cardiologist and carotid ultrasonographic examinations by a trained radiologist. RESULTS: The genotype distributions and allele frequencies between the hypertensive and control subjects and the relationship between the Glu298Asp variant and blood pressure, LVM and carotid artery IMT were determined. No differences in genotype distribution or allele frequencies were found between the hypertensive and control groups (the frequency of the Asp allele 0.299 vs. 0.288, respectively). Also, we could not find any association between the eNOS genotype and the measured cardiovascular complications. CONCLUSIONS: The Glu298Asp variant of the eNOS gene does not seem to be a major risk factor for cardiovascular alterations in the general population.     

血管内皮型一氧化氮合酶基因Glu298Asp多态性与老年心肌梗死的关系

目的　探讨老年人血管内皮型一氧化氮合酶 (eNOS)基因Glu2 98Asp多态性的分布及其与老年人心肌梗死的关系。　方法　测定 37例老年心肌梗死患者和 172例性别、年龄相匹配对照者的身高、体重、空腹血脂等指标 ,采用聚合酶链反应 (PCR)和限制性片断长度多态性 (RFLP)检测eNOS基因Glu2 98Asp多态性。　 结果　患病组Glu/Asp基因型高于对照组 (32 4 %和 18 0 % ) ,两组eNOS基因Glu2 98Asp多态性构成差异有显著性 (χ2 =3 87,P <0 0 5 )。无高血压患病亚组Glu/Asp基因型高于无高血压对照亚组 (35 0 %和 10 9% ) ,两亚组Glu2 98Asp多态性构成差异亦有显著性 (χ2 =7 4 3,P <0 0 1)。患病组 2 98Asp等位基因频率高于对照组 (16 2 %和 9 0 % ,P >0 0 5 ) ;无高血压患病亚组 2 98Asp等位基因频率亦高于无高血压对照亚组 (17 5 %和 5 4 % ) ,两组比较差异有显著性 (χ2 =6 82 ,P <0 0 1)。　结论　eNOS基因Glu2 98Asp多态性在中国老年人群中存在 ,Glu/Asp基因型和 2 98Asp等位基因可能是中国老年人心肌梗死的遗传易感指标。     

内皮型一氧化氮合酶基因多态性与冠心病的关系

内皮型一氧化氮合酶(eNOS)基因被列为冠心病(CHD)的一个候选易感基因。本文对与冠心病关系较为密切的三种eNOS基因多态性:4b/a、T786C和G894T的研究进展作一综述,对进一步认识冠心病的发病机制具有重要意义。     

内皮型一氧化氮合酶基因多态性与冠心病的研究进展

冠状动脉粥样硬化性心脏病（cronary atherosclerotic heart disease,CHD）简称冠心病,是指冠状动脉发生粥样硬化引起管腔狭窄或闭塞,导致心肌缺血缺氧或坏死引起的心脏病.吸烟、肥胖、高血压及代谢综合征等均已成为广为人知的几个冠心病重要危险因素.但也有患者没有这些危险因素存在,并且在一些个体中,常有明显的冠心病家族史,说明冠心病是环境与遗传危险因素动态相互作用所致的.目前已有诸多冠心病基因多态性研究,包括内皮型一氧化氮合酶（endothelial nitric oxide synthase,eNOS）.在近年的荟萃分析中显示,某些遗传变异可能为特定群体冠心病发病的危险因素之一.     

The T allele of the missense Glu(298)Asp endothelial nitric oxide synthase gene polymorphism is associated with coronary heart disease in younger individuals with high atherosclerotic risk profile.

AIMS: Nitric oxide (NO) plays a protective role during atherogenesis. In the endothelium, NO is synthesised by the constitutive NO synthase (ecNOS). We analysed the relation of the ecNOS Glu(298)Asp and 4a/b gene polymorphisms to coronary artery disease (CAD) and myocardial infarction (MI) in a population of 3250 German subjects (533 healthy controls and 2717 individuals who underwent coronary angiography). RESULTS: Although in the total sample, the ecNOS T allele was not associated with the risk of CAD (P=0.054) and the extent of this disease (P=0.078), a restriction to younger individuals (age相似文献   

Glu298Asp endothelial nitric oxide synthase gene polymorphism interacts with environmental and dietary factors to influence endothelial function

An endothelial nitric oxide synthase (eNOS) gene polymorphism (Glu298Asp) has been associated with cardiovascular disease. We investigated whether carriage of the polymorphism was associated with functional changes in the endothelium, and how genotype altered the harmful and beneficial impact of environmental influences on the endothelium. Endothelium-dependent, flow-mediated brachial artery dilatation (FMD) and endothelium-independent dilatation response to glyceryl trinitrate were measured using high-resolution ultrasound in 248 subjects (131 female, 117 male, aged 20 to 28) genotyped for the Glu298Asp polymorphism. Vascular function was compared between genotype groups and interactions with the proatherogenic risk factor, smoking, and the antiatherogenic influence of n-3 fatty acids (n-3FA) were investigated. Vascular function was not related to genotype in the group as a whole or within sexes. However, among males, smoking was associated with lower FMD in Asp298 carriers (nonsmokers 0.125+/-0.085 mm versus smokers 0.070+/-0.060 mm, P=0.006) but not in Glu298 homozygotes (nonsmokers 0.103+/-0.090 mm versus smokers 0.124+/-0.106, P=0.5). In the whole group, n-3FA levels were positively related to FMD in Asp298 carriers (reg coeff=0.023 mm/%, P=0.04, r=0.20) but not in Glu298 homozygotes (reg coeff=-0.019 mm/%, P=0.1). These differences between genotype groups were significant in interaction models. The Glu298Asp polymorphism is associated with differences in endothelial responses to both smoking and n-3 FA in healthy young subjects. These findings raise the possibility of genotype-specific prevention strategies in cardiovascular disease.     

2型糖尿病患者内皮型一氧化氮合酶基因(CA)n多态性分析

目的　探讨内皮型一氧化氮合酶 (eNOS)基因 (CA)n多态性与 2型糖尿病及 2型糖尿病患者血清中一氧化氮 (NO)含量的相关关系。　方法　采用聚合酶链反应 (PCR)技术结合聚丙烯酰胺凝胶电泳和硝酸银染色 ,检测不同个体基因型 ;硝酸还原酶法测定空腹血清NO含量 ;分光光度法测定空腹血清NOS含量。　结果　eNOS基因 (CA)n多态性存在 2 2种等位基因 ,所含CA重复次数分别为 19～ 4 0 ,其中 (CA) 3 0 (16 6bp)等位基因最常见。该位点杂合度为 0 85 ,多态信息量为 0 83。糖尿病组和对照组中 (CA) 3 4 等位基因频率分别为 7 5 %和 2 9% ,差异有显著性 (χ2 =5 8,P <0 0 5 ,OR =1 31,95 %CI =1 2 7～ 3 96 ) ;基因型为 (CA)n1(CA)n2 的 2型糖尿病个体 ,当n1≥ 34或n2 ≥ 34时 ,血清中NO的含量显著低于对照组 (P <0 0 5 )。　结论　eNOS基因 (CA) 3 4 可能与 2型糖尿病相关 ,该基因多态性与血清NO水平有一定关系。     

The endothelial nitric oxide synthase (Glu298Asp and -786T>C) gene polymorphisms are associated with coronary in-stent restenosis.

AIMS: Coronary stent deployment is a major advance in percutaneous treatment of ischaemic heart disease, but 10-40% of patients still develop angiographic restenosis by 6 months due to neointimal hyperplasia. Patient-specific factors, including genetic factors, can contribute to this process. We have conducted a prospective study to examine the involvement of genetic risk factors (eNOS, ACE, MMP-3, IL-6, and PECAM-1) in restenosis following coronary stent deployment. METHODS AND RESULTS: A total of 226 patients who underwent elective and successful coronary artery stenting to de novo lesions in native coronary arteries were studied. Two hundred and five (90.7%) patients were restudied by coronary angiogram at 6 months and the stented lesions were assessed using an automated quantitative angiography system. Genotype was determined by polymerase chain reaction (PCR) and restriction enzyme digestion. Restenosis rate, defined as >or=50% diameter stenosis, was 29.3%. The overall genotype frequency distributions were in Hardy-Weinberg equilibrium for all variants. Carriers of the 298Asp allele of the eNOS Glu298Asp polymorphism showed a higher frequency of restenosis with an odds ratio of 1.88 (95%CI: 1.01-3.51, P=0.043) compared to 298Glu homozygotes. Carriers of the -786C allele of the eNOS -786T>C polymorphism also showed a higher frequency of restenosis with odds ratio of 2.06 (95%CI: 1.08-3.94, P=0.028). These effects were essentially additive and were independent of other classical risk factors. Other studied genes did not show significant association with coronary in-stent restenosis. CONCLUSION: In patients with coronary artery disease, the possession of the 298Asp and -786C variants of the eNOS gene are a risk factor for coronary in-stent restenosis, demonstrating the importance of the nitric oxide system in restenosis.     

内皮型一氧化氮合酶基因G894T多态性与新疆维吾尔族原发性高血压的关联研究

目的探讨新疆维吾尔族人群内皮型一氧化氮合酶基因(endothelialnitricoxidesynthasegene,eNOS)第7外显子894G→T多态性与原发性高血压(essentialhypertension,EH)之间的关系。方法应用多聚酶链反应、限制性片段长度多态性技术(PCR-RFLP)对新疆地区375例EH患者(EH组)及正常血压者414例(NT组)的eNOS第7外显子894位进行基因分型,并采用生化技术测定其空腹血糖、血浆胆固醇、甘油三酯、胆红素,测定体重指数等水平。结果(1)eNOS基因第7外显子894G→T多态性符合Hardy-Weinberg平衡;GG、GT、TT基因型频率在维吾尔族EH患者及正常人群中分布分别为56.5%、28.3%、15.2%和65.9%、22.5%、11.6%,T等位基因频率分别为29.33%和22.83%,该位点各基因型频率与等位基因频率在维吾尔族高血压组和正常对照组中差异有统计学意义(P<0.05,OR=2.97,95%可信区间1.393~6.358)。(2)在EH组中GT+TT基因型者的收缩压[(171.36±22.30)mmHg,1mmHg=0.133kPa]和舒张压[(103.63±13.22)mmHg]均显著高于GG基因型者[(158.07±20.85)mmHg和(89.90±10.39)mmHg],两组比较差异有统计学意义(P<0.01)。结论eNOS基因第7外显子894G→T变异可能是中国新疆维吾尔族人群EH的一种遗传易感性指标。