Effect of polymorphisms of endothelial nitric oxide synthase on ischemic stroke: a case-control study in a Chinese population

BACKGROUND: Nitric oxide (NO) synthesized by endothelial nitric oxide synthase (eNOS) plays a key role in vascular regulation and atherosclerosis, therefore, eNOS may be a candidate gene for ischemic stroke (IS). However, it is still controversial whether eNOS polymorphisms are a risk factor for IS. METHODS: Three polymorphisms of the eNOS gene (-922A/G, -786T/C, 894G/T) were determined by using TaqMan SNP genotyping assay in 309 Chinese patients with IS and 309 Chinese controls. RESULTS: The frequency of eNOS -922 G allele was significantly higher in the patients than the controls (12.14% vs 8.09%, P=0.018). The distribution of eNOS genotypes differed insignificantly between the 2 groups. The frequency of the eNOS -786 CC genotype was higher in the patients than the controls (OR=3.819, P=0.029). With respect to -922A/G, the AG+GG genotype increased the risk for IS (OR=1.523, P=0.047). After adjustment for confounding factors, the odds ratios of -786 CC and -922 variant genotype (AG+GG) for IS were 4.580 and 1.656, respectively. However, haplotype analysis revealed the frequencies of Hap4 (GCG) and Hap7 (GCT) were significantly higher in the patients than the controls (P=0.035, 0.042). CONCLUSIONS: eNOS -922A/G and -786T/C may affect the susceptibility to IS and certain haplotypes of the eNOS gene may be associated with a higher susceptibility to IS.     

Angiotensin-Converting Enzyme and Endothelial Nitric Oxide Synthase Polymorphisms in Patients with Atrial Fibrillation

GENSINI, F., et al. ; Angiotensin-Converting Enzyme and Endothelial Nitric Oxide Synthase Polymorphisms in Patients with Atrial Fibrillation. Experimental studies have shown a significant increase in angiotensin-converting enzyme (ACE) expression in atrial tissue of AF patients. ACE regulates the synthesis of endothelial nitric oxide (NO), which modulates autonomic nervous activity involved in the development of AF. The aim of the study was to evaluate the prevalence of ACE insertion/deletion and endothelial NO synthase (eNOS) T-786C, G894T, and 4a/4b polymorphisms in 148 patients with persistent AF, compared with 210 control subjects. ACE insertion/deletion polymorphism genotype distribution and allele frequency were significantly different between patients and controls (   P < 0.0001   and   P < 0.0001   , respectively). ACE DD genotype was significantly associated with the risk of AF   (OR DD/ID + II = 3.24, P < 0.0001)   . Analysis of eNOS polymorphisms showed no significant difference in genotype distribution and allele frequency between patients and controls. The results suggest a possible role of ACE DD genotype as a predisposing factor to AF and a pathophysiological mechanism of ACE inhibition in reducing the incidence of AF in patients with left ventricular dysfunction. (PACE 2003; 26[Pt. II]:295–298)     

Association between the eNOS (Glu298Asp) and the RAS genes polymorphisms and premature coronary artery disease in a Turkish population

BACKGROUND: The renin-angiotensin system (RAS) and endothelial nitric oxide (NO) affect the pathogenesis of atherosclerosis and prognosis of coronary artery disease (CAD). Previous epidemiologic data suggested that genetic factors are more likely to affect young rather than old people. Our objective was to investigate the association between the polymorphisms of eNOS (Glu298Asp) and the RAS genes and premature CAD in a Turkish population. METHODS: A total of 115 Turkish patients with premature CAD and 83 controls were included in the study. ACE I/D, AT1R A/C, AGT T/M and eNOS Glu298Asp gene polymorphisms were analysed by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). RESULTS: It was found that increased premature CAD risk is associated with higher frequencies of the ACE DD [OR: 2.600 (CI 95% 1.395-4.847, p=0.002)], AGT MM [OR=2.407 (CI 95% 1.267-4.573, p=0.007)] and eNOS 894TT [OR=17.000 (CI 95% 3.952-73.125, p<0.001)] genotypes. Carriers of ACE DD+eNOS 894TT (p=0.002), AGT MM+eNOS 894TT (p=0.001), AT1R AA+eNOS 894TT and AT1R non-AA+eNOS 894TT (p=0.002) genotypes were significantly associated with the risk of premature CAD. CONCLUSIONS: This study indicates a synergistic contribution of RAS genes (ACE I/D, AGT T/M, AT1R T/C) and eNOS Glu298Asp polymorphisms to the development of the premature CAD.     

Angiotensin converting enzyme DD genotype is associated with hypertensive crisis

OBJECTIVE: The genetic background of hypertensive crisis is unknown. We examined the association of polymorphisms in genes involved in the renin-angiotensin-aldosterone-system with hypertensive crisis. DESIGN: Population-based case-control study. SETTING: Emergency department at a tertiary care university hospital. PATIENTS: A total of 182 patients with essential hypertension who were admitted to an emergency department for treatment of hypertensive crisis and 182 age- and sex-matched healthy individuals. INTERVENTIONS: None. MEASUREMENTS: Analysis of polymorphisms in genes coding for angiotensinogen (AJT 704T-->C), angiotensin II receptor 1 (AGTR1 1166A-->C), renin (REN 2646G-->A), renin-binding protein (RENBP 61T-->C), alpha-adducin (ADD1 1378G-->T), beta-2-adrenergic receptor (ADRB2 46A-->G, 79C-->G), and angiotensin I converting enzyme (ACE I/D) was performed by polymerase chain reaction and restriction fragment length polymorphism analysis.MAIN RESULTS Among patients, the ACE I/D polymorphism showed a deviation from Hardy-Weinberg equilibrium (p =.01). In controls, all polymorphisms were in the Hardy-Weinberg equilibrium. The frequency of the DD genotype was increased in patients (n = 70, 38.5%) vs. controls (n = 51; 28.0%;p =.03; odds ratio, 1.61; 95% confidence interval, 1.03-2.50), which was due to the DD genotype in 40 male patients (44%) vs. 23 in male controls (25.3%;p =.004; odds ratio, 3.48; 95% confidence interval, 1.47-8.30). There were no differences in genotype distributions among other polymorphisms. CONCLUSION: We demonstrate a possible association of the DD genotype with hypertensive crisis in men.     

云南汉族高血压病6个候选基因相互作用研究

目的探讨AGT、ACE、eNOS、ET-2、ANP和NPRC等6个基因多态性与高血压病的相关性及其相互作用。方法用基因芯片检测技术,对100例高血压病患者及97例健康对照者进行AGTM235T、ACEI／D、eNOSGlu298Asp、ET-2A985G、ANPT2238C和NPRCA．55C等位点基因多态性检测。结果NPRCA．55C位点的CC基因型频率（0．540）与对照组（0．237）比较差异有极显著性意义（X^2=18．973,P=-0．0000）,OddRatio=3．777（95％CI：2．050～6．960）;ET-2A985G位点G等位基因频率（0．925）与对照组（0．851）比较,差异有显著性意义（X^2=5．507、P=0．0190）,Odd Ratio=2．648（95％CI：1．073—6．536）。用MDR方法分析以上6个位点基因-基因交互作用,显示两位点ET-2／NPRC模型为最佳模型,该模型的Odd Ratio为4．002（95％CI：2．1597～7．4159）。结论云南汉族NPRCA-55CCC基因型和ET-2A985GG等位基因可能与高血压病易感性相关。ET-2A985G和NPRCA．55C两个基因多态性之间可能存在基因-基因交互作用。     

内皮型一氧化氮合酶基因多态性与高血压病发病相关性的研究

目的 研究内皮型一氧化氮合酶（eNOS）基因启动子-786位点及第七外显子第894位点多态性与高血压病发病的相关性.方法 采用病例对照研究的方法,以215名高血压病患者与108名健康中老年人的血白细胞为样本,应用聚合酶链反应一限制性片段长度多态性技术检测两组的内皮型一氧化氮合酶基因启动子-786位点T/C多态性及第七外显子第894位点G/T多态性,比较两组的基因型和等位基因的分布频率.通过两基因位点多态性的分布频率研究两基因变异在高血压病的发病中是否存在协同作用.结果 eNOS基因启动子-786位点T/T、T/C和C/C基因型在高血压病组中分别为22.79%、50.70%、26.51%,在正常中老年人组中分别为36.11%、52.78%、11.11%,此位点高血压病组与正常中老年人组的基因分布频率差异有显著性.eNOS基因第七外显子第894位点G/G、G/T和T/T基因型在高血压病组中分别为69.30%、22.33%、8.37%,在正常中老年人组中分别为82.41%、15.74%、1.85%,此位点高血压病组与正常中老年人组的基因分布频率差异有显著性.当如上两基因型为CC＋TT或TC＋TT时,经计算患高血压病的OR值明显大于基因型为TT＋GG者.结论 ①eNOS基因启动子-786位点及第七外显子第894位点基因多态性与高血压病的发病有一定程度的相关性;②eNOS基因启动子-786位点T/T及第七外显子894位点G/G是高血压病的保护性基因;③两基因变异在高血压病的发病中可能有一定程度的协同作用.     

云南省汉族健康人群六个原发性高血压候选基因多态性分布

目的 探讨肾素血管紧张素系统(RAS)、血管内皮和钠肽系统中AGT、ACE、eNOS、ET-2、ANP和NPRC等6个原发性高血压候选基因多态性在云南汉族健康人群中的分布,为进一步研究其在原发性高血压等心血管疾病发生中的作用提供本地信息.方法 用基因芯片检测技术,对97例健康者进行AGTM235T(MM、MT、TT)、ACE I/D(II、ID、DD)、eNOS Glu298Asp(EE、ED、DD)、ET-2 A985G(AA、AG、GG)、ANPT2238C(TT、TC、CC)和NPRC A-55C(AA、AC、CC)等位点基因多态性检测.结果 ①云南汉族97例健康人群中AGT M235T位点的MM、MT、TT基因型频率分别为0.052、0.381、0.567;M和T的等位基因频率分别为0.242、0.758.②ACE I/D突变的II、ID、DD基因型频率分别为0.340、0.598、0.062;I和D等位基因频率分别为0.680、0.320.@eNOS Glu298Asp位点的EE、ED、DD基因型频率分别为0.845、0.144、0.011;E和D等位基因频率分别为0.918、0.082.④ET-2 A985G位点的AA、AG、GG基因型频率分别为0.020、0.258、0.722;A和G等位基因频率分别为0.149、0.851.⑤ANPT2238C位点的TT、TC基因型频率分别为0.959、0.041,未检出CC基因型;T和C等位基因频率分别为0.979、0.021.⑥NPRC A-55C的AC、CC基因型频率分别为0.763、0.237,未检出AA基因型;A和c等位基因频率分别为0.381、0.619.结论 云南汉族健康人群AGT M235T、ACE I/D、eNOS Glu298Asp(E298D)、ET-2 A985G、ANP 12238C和NPRC A-55C等6个位点基因多态性有地区特征.     

Increased cardiac endothelial nitric oxide synthase expression in patients taking angiotensin-converting enzyme inhibitor therapy

BACKGROUND: The efficacy of angiotensin-converting enzyme (ACE) inhibitors has been demonstrated in large clinical trials, but knowledge of the underlying mechanisms remains incomplete. Therefore, this study investigated the impact of ACE inhibitor therapy on cardiac nitric oxide (NO) synthases in patients with coronary artery disease (CAD) or heart failure. PATIENTS AND METHODS: The mRNA expression was quantified by standard calibrated competitive RT-PCR, protein expression by Western blotting and NOS activity by monitoring the conversion of [3H]arginine to [3H]citrulline during enzymatic formation of NO in tissue homogenates of myocardium of patients with, or without, ACE inhibitor treatment before elective coronary artery bypass grafting or heart transplantation. RESULTS: The mRNA expression (amol microg(-1) RNA) of endothelial NO synthase (eNOS) was higher (22.5 +/- 4.8, n = 23) in the atrial myocardium of patients taking ACE inhibitor treatment, before elective coronary artery bypass grafting, compared with patients not taking this therapy (8.9 +/- 0.7, n = 33, P < 0.0001). The ACE inhibitor therapy increased eNOS protein expression from [(9 +/- 0.7) relative units (RUs) to (12 +/- 0.9) RUs, P < 0.05, respectively] and cardiac NOS activity from 17.6 +/- 1.3 to 23.7 +/- 1.1 pmol mg protein(-1) min(-1) (P < 0.001, respectively). Inducible and neuronal NO synthase expression was not changed by the ACE inhibition. A similar up-regulation of eNOS by ACE inhibition was found in the left ventricles of patients with heart failure. The augmented endothelial NOS expression and activity was not the result of differences in clinical characteristics and concomitant therapy between the patient groups. CONCLUSION: Increased eNOS expression and activity might contribute to the beneficial effects of ACE inhibitor therapy in the treatment of CAD and heart failure.     

Angiotensin converting enzyme DD genotype affects the changes of plasma plasminogen activator inhibitor-1 activity after primary percutaneous transluminal coronary angioplasty in acute myocardial infarction patients

Angiotensin converting enzyme (ACE) DD genotype, and plasminogen activator inhibitor (PAI-1) 4G/4G genotype have been reported to affect PAI-1 activity in control subjects and atherosclerotic patients, but no data are available on the influence of angiotensin II type 1 receptor (AT1R) A1166C polymorphism on the inhibitor levels. The degree of fibrinolytic activation after percutaneous transluminal coronary angioplasty (PTCA) has been found to affect the risk of restenosis. The aim of this study was to investigate the possible influence of ACE I/D, AT1R A1166C, and PAI-1 4G/5G polymorphisms on the changes of PAI-1 activity after primary successful percutaneous transluminal angioplasty. In 29 consecutive acute myocardial infarction patients, undergoing primary successful angioplasty, genotyping of ACE I/D, AT1R A1166C, and PAI-1 4G/5G polymorphisms was performed by polymerase chain reaction and restriction fragment length polymorphism analysis, and PAI-1 plasma activity (chromogenic method) was assessed before and after angioplasty. Following angioplasty, PAI-1 activity increased in 10 of 29 patients and decreased or remained unchanged in 19 of 29. ACE DD genotype was significantly (P = 0.04) associated with an increase of PAI-1 activity post angioplasty (OR DD/ID+II = 6.5, CI 95% 4.83-8.22). Whereas no effect of PAI-1 4G/5G and AT1R A1166C polymorphisms on PAI-1 response to angioplasty was demonstrated, these data suggest that renin-angiotensin system genes are involved in the regulation of the fibrinolytic response to balloon injury, possibly affecting angiotensin converting enzyme activity. This interaction between the renin-angiotensin system and hemostasis may be a mechanism by which ACE DD genotype affects the risk of restenosis after percutaneous transluminal angioplasty.     

Endothelial nitric oxide synthase gene is associated with vessel stenosis in Korean population

BACKGROUND: Nitric oxide (NO) produced by endothelial NO synthase (eNOS) mediates endothelium-dependent vasodilation and antithrombotic action. Controversial results regarding the association of eNOS gene polymorphisms with vessel stenosis have been reported. METHODS: Age- and sex-matched 932 individuals (656 subjects having 1-, 2-, and 3-stenosed vessels and 276 controls without stenosis) living in Seoul and surrounding suburbs were selected. A GT missense mutation in exon 7 (894GT) was screened using PCR-restriction fragment length polymorphism analysis. The genotypes of a 27-bp insertion/deletion in intron 4 (eNOS4b/a) and a TC mutation in promoter region of -786 (-786TC) were determined by the banding pattern on gel electrophoresis and a commercially available minisequencing protocol (SNaPshot), respectively. RESULTS: The eNOS4a allele was highly linked to the -786C allele (r=0.93, P<0.0001) while there was no linkage between eNOS4a allele and 894T allele or between 894T allele and -786C allele. Furthermore, 894T allele, but not eNOS4a (-786C) allele, was associated with the presence, but not the number, of stenosed vessels (odds ratio=1.57 for dominant effect of the T allele, P<0.05, and 1.49 for additive effect, P<0.05). Multiple logistic regression analysis revealed that 894T allele and hypertension were predictive independent risk factors for the presence of vessel stenosis. CONCLUSION: Our data suggest that eNOS gene polymorphisms may play an important role in the pathogenesis of vessel stenosis in Korean population.     

Candidate gene polymorphisms and their association with hypertension in Malays

BACKGROUND: Knowledge of candidate gene polymorphisms in a population is useful for a variety of gene-disease association studies, particularly for some complex traits. A single nucleotide variant of the angiotensinogene gene (AGT M235T) and endothelial nitric oxide synthase gene (eNOS G894T) have been associated with hypertension. METHOD: A cross-sectional study consisting of 200 hypertensives and 198 age- and sex-matched controls was conducted. Subjects involved in this study were pure Malay for 3 generations. The AGT M235T and eNOS G894T polymorphisms were determined by PCR-RFLP method. RESULTS: The distribution of M235T genotype in the population was 3.5% for MM, 30.4% for MT and 66.1% for TT. No significant difference was observed in genotype (chi(2)=1.30, p=0.52) and allele (chi(2)=0.87, p=0.35) frequencies among the 2 study group. In contrast, the distribution of genotypes for G894T was 74.1% for GG, 24.6% for GT and 1.3% for TT, respectively. Similarly, no significant difference was observed in genotype (chi(2)=0.94, p=0.33) and allele (chi(2)=0.60, p=0.44) frequencies between both study groups. CONCLUSION: The AGT M235T and eNOS G894T polymorphisms are unlikely to play an important role in the pathogenesis of hypertension in Malays.     

Lack of association of eNOS (G894T) and p22phox NADPH oxidase subunit (C242T) polymorphisms with systemic sclerosis in a cohort of French Caucasian patients

OBJECTIVE: To assess the influence of endothelial nitric oxide synthase (eNOS) and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase polymorphisms on the susceptibility of patients to and clinical expression of systemic sclerosis (SSc). METHODS: Seventy-seven French Caucasian patients with SSc were studied. Patients and ethnically matched controls (n=49) were genotyped, by restriction enzyme digestion of polymerase chain reaction (PCR) products, for G894T polymorphism in exon 7 of the eNOS gene and for C242T polymorphism of the gene encoding the p22(phox) NADPH oxidase subunit. RESULTS: The allele and genotype frequencies of the polymorphisms did not differ between patients with SSc and the controls. Moreover, there was no association between these polymorphisms and disease phenotypes. CONCLUSION: Our results indicate that eNOS (G894T) and p22(phox) (C242T) polymorphisms do not influence susceptibility to and the course of systemic sclerosis.     

The relationship between ACE insertion/deletion polymorphism and coronary artery disease with or without myocardial infarction

OBJECTIVES: Presence of the D allele or homozygosity for the deletion (D) allele of the angiotensicen-converting enzyme (ACE) insertion/deletion (I/D) polymorphism has been discussed as potent risk factor for coronary artery disease (CAD) and myocardial infarction (MI). The D allele is associated with higher levels of circulating ACE and therefore may predispose one to cardiovascular damage. DESIGN AND METHODS: The study presented here was performed to investigate the association between the ACE genotype and ACE levels. The study group was comprised of 118 angiographically verified CAD patients. 65 patients were MI (+) and 53 patients were MI (-) in this group. A total of 70 healthy individuals were taken as controls. Genomic DNA of 188 subjects was extracted from whole blood. The polymerase chain reaction was used for ACE genotyping, and ACE levels were measured by ELISA. RESULTS: The D allele was found to be significantly more frequent in patients with MI (+) compared with controls (P = 0.024). ACE levels were significantly higher in both MI (-) and MI (+) groups with CAD patients than in controls (P < 0.005). Plasma ACE level was higher in all three groups in the DD genotype compared to II genotype. In groups I and III, this was statistically significant (P < 0.0001, P < 0.01). CONCLUSIONS: It was shown that the I/D polymorphism in the gene for ACE is a genetic risk factor for CAD patients who have a history of MI. ACE insertion/deletion gene polymorphism is also associated with plasma ACE levels in CAD patients with a history of MI.     

醛糖还原酶和内皮型一氧化氮合酶基因多态性并存与糖尿病肾病发病的相关性

背景有关资料显示,醛糖还原酶基因启动子区C-106T多态和内皮型一氧化氮合酶基因第七外显子GLU298ASP(894G→T)多态与糖尿病肾病有关,上述基因多态并存时,2型糖尿病患者糖尿病肾病的发病风险是否明显增加有待进一步研究.目的探讨染色体7q35区醛糖还原酶基因启动子区C-106T多态和内皮型一氧化氮合酶基因第七外显子GLU298ASP(894G→T)多态并存时与中国北方汉族人群糖尿病肾病发病的关系.设计病例-对照,对比观察.单位青岛大学医学院附属医院内分泌科.对象选择2002-11/2005-04在青岛大学医学院附属医院内分泌科住院2型糖尿病患者139例,男54例,女85例,年龄(64±8)岁.符合1999年世界卫生组织关于糖尿病诊断和分类标准.根据24 h尿微量白蛋白排泄率分为2组糖尿病肾病组61例和非糖尿病肾病组78例.选择同期本院体检健康成人63名为对照组,男24名,女39名;年龄50～78 岁.纳入对象均为汉族,且对检测项目知情同意.方法运用聚合酶链反应限制性片段长度多态性技术、DNA测序技术及琼脂糖凝胶电泳分离技术检测纳入对象的醛糖还原酶基因启动子区C-106T多态位点和内皮型一氧化氮合酶基因第7外显子GLU298ASP(894G→T)多态位点的等位基因和基因型.主要观察指标①醛糖还原酶和内皮型一氧化氮合酶基因多态性.②糖尿病肾病危险因素的多元逐步回归分析结果.③醛糖还原酶C-106T多态和内皮型一氧化氮合酶894G→T多态与糖尿病肾病相对危险度.结果2型糖尿病患者139例和健康人63名全部进入结果分析.①糖尿病肾病组内皮型一氧化氮合酶基因第7外显子894G→T多态位点的T等位基因和TG基因型频率明显高于非糖尿病肾病组和对照组(χ2=8.261,19.629,P＜0.01).②糖尿病肾病组醛糖还原酶基因启动子区C-106T多态位点的T等位基因和CT基因型频率明显高于非糖尿病肾病组和对照组(χ2=6.343,8.940,P＜0.05,0.01).③将上述基因多态联合分析发现,糖尿病肾病组的TG/CT基因型频率明显高于非糖尿病肾病组和对照组(χ2=6.972,P＜0.01);GG/CC基因型频率显著低于非糖尿病肾病组和对照组(χ2=13.304,P＜0.01).④糖基化血红蛋白、收缩压、总胆固醇、内皮型一氧化氮合酶基因的第七外显子894G→T多态及醛糖还原酶基因启动子区C-106T多态均是糖尿病肾病的独立危险因素(Wald=5.627,4.92,P＜0.05).⑤GG/CC基因型可能是糖尿病肾病的保护基因型(OR=0.25,P＜0.01);GG/CT或TG/CC基因型携带者糖尿病肾病的危险性增加2.3倍,TG/CT基因型携带者糖尿病肾病的危险性增加4.8倍.结论内皮型一氧化氮合酶基因第7外显子894G→T多态位点的T等位基因和TG基因型和醛糖还原酶基因启动子区C-106T多态位点的T等位基因和CT基因型增加2型糖尿病患者发生糖尿病肾病的危险性,两种基因多态并存时,糖尿病肾病的发病风险明显增加.     

eNOS基因G894T多态性与糖尿病肾病易感性的荟萃分析

目的:系统评价内皮型一氧化氮合酶(endothelial nitric oxide synthase,eNOS)基因G894T多态性与糖尿病肾病(diabetic nephropathy,DN)易感性之间的关系。方法:全面检索建库以来至2019年6月与eNOS基因G894T多态性及DN易感性相关的文献,通过纽卡斯尔渥太华(Newcastle-Ottawa Scale,NOS)标准对纳入文献进行质量评价。采用Stata 15.0进行统计学分析,通过计算发病风险比值比(odds ratio,OR)及95%置信区间(confidence interval,CI)来评估eNOS基因G894T多态性与DN易感性之间的关系。结果:共纳入29项病例对照研究,包含实验组5345例,对照组4827例。分析结果显示eNOS基因G894T多态性可显著增加DN发病风险[等位基因模型T vs G:OR=1.39(95%CI:1.19~1.64),P<0.001;纯合子模型TT vs GG:OR=1.34(95%CI:1.02~1.77),P=0.038;显性遗传模型TT+GT vs GG:OR=1.48(95%CI:1.21~1.81),P<0.001;隐性遗传模型TT vs GG+GT:OR=1.30(95%CI:1.04~1.63),P=0.022;杂合子模型TG vs GG:OR=1.43(95%CI:1.17~1.75),P=0.001]。结论:eNOS基因G894T多态性可明显增加DN易感性。     

Contribution of genetic polymorphism in the renin-angiotensin system to the development of renal complications in insulin-dependent diabetes: Genetique de la Nephropathie Diabetique (GENEDIAB) study group.

Diabetic nephropathy is a glomerular disease due to uncontrolled diabetes and genetic factors. It can be caused by glomerular hypertension produced by capillary vasodilation, due to diabetes, against constitutional glomerular resistance. As angiotensin II increases glomerular pressure, we studied the relationship between genetic polymorphisms in the renin-angiotensin system-angiotensin I converting enzyme (ACE), angiotensinogen (AGT), and angiotensin II, subtype 1, receptor-and the renal involvement of insulin-dependent diabetic subjects with proliferative retinopathy: those exposed to the risk of nephropathy due to diabetes. Of 494 subjects recruited in 17 centers in France and Belgium (GENEDIAB Study), 157 (32%) had no nephropathy, 104 (21%) incipient (microalbuminuria), 126 (25 %) established (proteinuria), and 107 (22%) advanced (plasma creatinine > or = 150 micromol/liter or renal replacement therapy) nephropathy. The severity of renal involvement was associated with ACE insertion/deletion (I/D) polymorphism: chi2 for trend 5.135, P = 0.023; adjusted odds ratio attributable to the D allele 1.889 (95% CI 1.209-2.952, P = 0.0052). Renal involvement was not directly linked to other polymorphisms. However, ACE I-D and AGT M235T polymorphisms interacted significantly (P = 0.0166): in subjects with ACE ID and DD genotypes, renal involvement increased from the AGT MM to TT genotypes. Thus, genetic determinants that affect renal angiotensin II and kinin productions are risk factors for the progression of glomerular disease in uncontrolled insulin-dependent diabetic patients.     

Angiotensin Converting Enzyme and Angiotensin II Type 1 Receptor Polymorphisms in Patients with Coronary Aneurysms

BACKGROUND: Conflicting results have been reported regarding the association of gene polymorphisms in the renin-angiotensin system (RAS) with different aspects of coronary artery disease (CAD), such as myocardial infarction, neointimal hyperplasia or coronary artery vasomotion. Since previous studies have linked angiotensin II to aneurysmal disease, our study hypothesis was that RAS gene polymorphisms may be associated with aneurysm remodeling in response to CAD. METHODS: The study population was selected from a series of 3862 consecutive patients who underwent coronary angiography in our institution. One hundred and thirteen consecutive patients with at least one coronary aneurysm (CA) were compared to 226 randomized control patients without CA. DNA was extracted from white blood cells. The angiotensin-converting enzyme (ACE) I/D and angiotensin type 1 receptor (AT1-R) A/C polymorphisms were detected using previously published techniques. RESULTS: The distributions of the three ACE genotypes were similar in both groups: CA: 13%, 46%, and 41% for II, ID, and DD respectively; controls: 18%, 41%, and 41% for II, ID, and DD respectively, p = 0.45. The distributions of the three AT1-R genotypes were also similar in both groups: CA: 54%, 41%, and 5% for AA, AC, and CC respectively; controls: 55%, 33%, and 12%, for AA, AC, and CC respectively, p = 0.08. CONCLUSION: Our results provide further information on the role of RAS polymorphisms on specific mechanisms implicated in CAD. Although an activated RAS may theoretically promote aneurysm formation, the 2 RAS polymorphisms analyzed in this study are not associated with this process in coronary arteries.     

ACE 基因 I/D 多态性与动脉血栓性脑梗死的关联性研究

目的研究血管紧张素转换酶（ACE）基因I/D多态位点与动脉血栓性脑梗死的关联性及相关机制。方法选取动脉血栓性脑梗死患者112例和年龄、性别匹配的对照组180例,采用PCR-AFLP技术对ACE基因I/D位点进行分型。结果单因素分析提示病例组收缩压水平（138.1±19.7 mmHg）显著高于对照组（126.6±20.6 mmHg）（t=4.716,P<0.001）;病例组舒张压水平（88.9±10.1 mmHg）显著高于对照组（79.9±10.0 mmHg）（t=7.450,P<0.001）。病例组中ACE基因I/D位点D等位基因频率和DD基因型频率分布均显著高于对照组（等位基因：χ²=4.953,P=0.026; 基因型：χ²=6.303,P=0.043）。病例组和对照组中ACE基因I/D位点基因型DD携带者收缩压及舒张压水平显著高于基因型ID及II携带者。结论ACE基因I/D位点等位基因D可能是汉族人群动脉血栓性脑梗死遗传易感基因。等位基因D可能通过升高个体血压的机制导致动脉血栓性脑梗死发生。     

The D allele of angiotensin I-converting enzyme gene insertion/deletion polymorphism is associated with the severity of atherosclerosis

BACKGROUND: Angiotensin II is produced primarily by angiotensin I-converting enzyme (ACE) within atherosclerotic lesions and ACE level in plaques correlates with the severity of vessel wall damage. Therefore, we investigated the possible association of ACE gene insertion/deletion (I/D) polymorphism and the severity of atherosclerosis, estimated on the basis of the number of coronary stenoses and critical arterial occlusions observed during coronary angiography. METHODS: The study cohort included 172 patients with angiographically confirmed premature coronary artery disease. The ACE gene I/D polymorphism was genotyped using a PCR method. RESULTS: The frequencies of DD genotype, D allele carrier-state (DD+ID genotypes) and the D allele increased with the number of stenoses in coronary vessels. D allele carriers (DD+ID genotypes) were more frequent in the subgroup of patients with stenoses in at least four coronary vessels than in other patients including subjects with one-, two- and three-vessel disease (97.4% vs. 74.4%, OR=13.05, 95% CI: 1.81-100.00, chi2=9.84, p=0.0017). Furthermore, the D allele was significantly more frequent in patients with critical arterial occlusions (>90%) than in subjects without critical stenoses (61.1% vs. 49.3%, chi2=9.84, p=0.023). CONCLUSIONS: The ACE I/D polymorphism influences individual differences in severity of coronary artery disease and the D allele promotes generation of numerous and critical atherosclerotic lesions.     

Association study of ACE2 (angiotensin I-converting enzyme 2) gene polymorphisms with coronary heart disease and myocardial infarction in a Chinese Han population

Results are accumulating that ACE2 (angiotensin I-converting enzyme 2) might act as a protective protein for cardiovascular diseases; however, only a few studies in human populations have been carried out. This prompted us to perform a case-control study to investigate the relationship of ACE2 polymorphisms with CHD (coronary heart disease) and MI (myocardial infarction). Three single nucleotide polymorphisms in the ACE2 gene (1075A/G, 8790A/G and 16854G/C) were genotyped by PCR-RFLP (restriction-fragment-length polymorphism) in 811 patients with CHD (of which 508 were patients with MI) and 905 normal controls in a Chinese population. The polymorphisms were in linkage disequilibrium (r(2)=0.854-0.973). Analyses were conducted by gender, because the ACE2 gene is on the X chromosome. In females, an association was detected with MI for 1075A/G (P=0.026; odds ratio=1.98) and 16854G/C (P=0.028; odds ratio=1.97) in recessive models after adjusting for covariates. In male subjects, two haplotypes (AAG and GGC) were common in frequency. In male subjects not consuming alcohol, the haplotype GGC was associated with a 1.76-fold risk of CHD [95% CI (confidence interval), 1.15-2.69; P=0.007] and a 1.77-fold risk of MI (95% CI, 1.12-2.81; P=0.015) with environmental factors adjusted, when compared with the most common haplotype AAG. In conclusion, the results of the present study indicate that common genetic variants in the ACE2 gene might impact on MI in females, and may possibly interact with alcohol consumption to affect the risk of CHD and MI in Chinese males.