Interaction between angiotensin-converting enzyme genotype and glycaemic control influences lipoprotein levels in type 2 diabetes mellitus

AIMS: To evaluate the influence of the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism on lipid levels in patients with Type 2 diabetes. PATIENTS AND METHODS: 109 patients with Type 2 diabetes were included. The patients were not on any lipid-lowering treatment. The groups with different ACE genotypes had similar ages, sex distributions, body mass indices, systolic blood pressures and indices of glycaemic control. ACE gene I/D polymorphism was determined using polymerase chain reaction. RESULTS: The mean apolipoprotein B (apoB) level was significantly higher in the group of DD homozygotes compared with the subjects with at least one insertion allele (DD: 1.21 +/- 0.25 g/l vs. ID + II: 1.04 +/- 0.27 g/l; P = 0.007). Significant correlations between glycated haemoglobin (HbA1c) and both apoB and cholesterol levels were found (r = 0.27; P < 0.01). For the apoB, this correlation was highly significant in the DD-genotype subgroup (r = 0.54; P < 0.01), and was not significant in the subgroup of patients with genotypes ID or II. In the multivariate analysis, HbA1c and the interaction of genotype DD with HbA1c were significant independent predictors of apoB (r2 = 0.17) and cholesterol levels. CONCLUSION: The present study showed that the interaction between the DD genotype of angiotensin-converting enzyme and chronic hyperglycaemia (expressed by HbA1c level) is related to higher plasma levels of atherogenic lipoproteins, such as apoB and cholesterol, in patients with Type 2 diabetes.     

血管紧张素转化酶基因多态性与老年高血压及合并糖尿病的相关性研究

目的 探讨血管紧张素转化酶(ACE)基因插入/缺失(I/D)多态性与老年人原发性高血压及合并糖尿病患者的关系.方法 应用聚合酶链反应(PCR)技术对60名正常对照组,105例老年高血压患者,38例老年高血压合并糖尿病患者进行ACE基因I/D多态性检测.结果 老年高血压患者中的DD基因型频率(0.352)和等位基因频率(0.543),老年高血压合并糖尿病患者的DD基因型频率(0.421)和等位基因频率(0.579)均明显高于正常对照组的0.133和0.250,而老年高血压组与老年高血压合并糖尿病组患者的DD基因型频率和D等位基因频率之间的差别无显著性.结论 ACE基因缺失型是老年高血压的危险因素,但ACE基因缺失不是糖尿病的危险因素之一.     

Frequency of angiotensin-converting enzyme gene polymorphism in Turkish type 2 diabetic patients

We aimed to investigate the angiotensin-converting enzyme (ACE) gene polymorphism, ACE activity and their associations with diabetic complications in Turkish patients with type 2 diabetes mellitus. A total of 143 patients and 133 controls were screened for ACE gene I/D polymorphism by using polymerase chain reaction. Serum ACE activities were determined spectrophotometrically. There was no significant difference in the distribution of ACE I/D genotypes between patients and controls. The patients with DD genotype had a higher ACE activity than those with ID and II. Hypertensive diabetic patients with DD genotype had higher ACE activities than those with ID and II. There was no significant difference in the distribution of ACE I/D genotypes between patients with and without nephropathy, retinopathy and hypertension except for patients with and without neuropathy. In patients with DD genotype, creatinine clearance correlated with duration of diabetes. The grade of retinopathy was correlated with duration of diabetes in DD and ID genotypes. The highest ACE activity was measured in hypertensive diabetics with DD genotype. ID genotype was suggested to be a risk factor and II was suggested to be protective for diabetic neuropathy. The DD and ID genotypes might be a predictor for the development of retinopathy in relation to duration of diabetes.     

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.     

Lack of association between angiotensin-converting enzyme gene polymorphism and type I aortic dissection

The relationship between angiotensin-converting enzyme (ACE) gene polymorphism and type I aortic dissection was examined in 205 unrelated hypertensives. A total of 94 patients underwent emergency repair due to type I aortic dissection, confirmed by computed tomography, and the remaining 111 were controls. Polymerase chain reaction was used to confirm that ACE gene polymorphism was due to insertion (I) or deletion (D) of a 287 base pair (bp) DNA sequence within intron 16. The genotype distribution and allele frequency of ACE I/D polymorphism between patients and controls were not statistically significant. When the frequency of at least one D allele carrier (DD or ID genotype) was compared with the II homozygous genotype, there was also no significant difference between the study groups. The findings revealed no association between ACE I/D polymorphism and aortic dissection. We conclude that I/D mutation of the ACE gene does not seem to be a risk factor for aortic dissection.     

A polymorphic locus in the intron 16 of the human angiotensin-converting enzyme (ACE) gene is not correlated with complex regional pain syndrome I (CRPS I).

Exaggerated neurogenic inflammation has been recognized to be one reason for many CRPS symptoms. Since angiotensin-converting enzyme (ACE) is a key enzyme for the termination of neurogenic inflammation, it has been selected as a candidate gene for CRPS predisposition. A previous report of an insertion/deletion (I/D) polymorphism in intron 16 within the ACE gene implicated an increased risk to develop CRPS I associated with the D allele. However, in the present study the D allele frequency was not increased in CRPS I cases (0.51 for D allele, 0.49 for I allele). Furthermore, there was no co-segregation of any genotype (DD, ID, II) with the CRPS phenotype in 12 selected familial CRPS I cases from six CRPS I families. In conclusion, the results presented herein render this particular ACE gene polymorphism unlikely to be a predisposing factor for CRPS I.     

The effect of angiotensin-converting enzyme polymorphism on hemodynamic response to endotracheal intubation in hypertensive patients

Endotracheal intubation elicits a hemodynamic response associated with increased heart rate and blood pressure that is influenced by the angiotensin-converting enzyme (ACE) insertion (I)/deletion (D) genetic polymorphism which may be of importance also for the pressure response to anesthesia. A total of 337 patients underwent abdominal surgery in general anesthesia and 16% were D/D-homozygotes, 45% were I/D heterozygotes and 39% of the patients were I/I homozygotes. Before surgery most patients were in treatment for arterial hypertension. Systolic and diastolic pressure, heart rate and concentrations of catecholamines in blood were determined before and after induction of anesthesia and for up to 10?minutes following endotracheal intubation. Anesthesia decreased blood pressure and for patients presenting ID and DD, blood pressure and heart rate reached similar levels but compared to II-homozygotes, D-carriers demonstrated significantly higher levels for systolic pressure and heart rate before and after intubation (p?相似文献   

Angiotensin-converting enzyme genotype, albuminuria and plasma fibrinogen in type 2 diabetes mellitus

AIMS: Increased fibrinogen level is considered an important atherosclerosis risk factor. Patients with type 2 diabetes frequently have increased fibrinogen levels. The aim of the present study was to examine the effect of angiotensin-converting enzyme (ACE) gene polymorphism and the effects of the diabetic environment on plasma fibrinogen in type 2 diabetes. PATIENTS AND METHODS: The study group included 125 patients with type 2 diabetes (40 men, 85 women). The average age of patients was 62 +/- 10 years. Fibrinogen concentration was determined with the thrombin coagulation test. ACE insertion/deletion (I/D) polymorphism was detected using polymerase chain reaction (PCR) assay. RESULTS: II homozygotes (n = 17) had the highest mean fibrinogen levels, ID heterozygotes (n = 75) had medium levels and DD homozygotes (n = 33) had the lowest (p = 0.054, ANOVA). II homozygotes also had significantly higher mean fibrinogen level than ID/DD carriers (4.3 +/- 1.7 vs. 3.5 +/- 1.3 g/l; p = 0.015). The indices of renal functions, i.e. albuminuria (r = 0.37; p < 0.0001) and serum creatinine (r = 0.22; p = 0.015), significantly correlated with fibrinogen levels. The correlation between albuminuria and fibrinogen was significant in the subgroups with genotypes II (r = 0.76; p = 0.001) and ID (r = 0.37, p = 0.002), whereas in the subgroup of DD homozygotes this relationship did not reach statistical significance. In the multivariate regression analysis with age, sex, BMI, creatinine, albuminuria and ACE genotype as independent variables, albuminuria was the only significant predictor of fibrinogen level (p < 0.0001). After interaction between the ACE genotype and albuminuria was included into multivariate analysis, the interaction became the only independent predictor of plasma fibrinogen level (p < 0.0001) in the model, and the model explained 25% of the plasma fibrinogen variance. CONCLUSION: ACE gene polymorphism is associated with plasma fibrinogen level in type 2 diabetes. This association is mediated by an interaction between ACE genotype and albuminuria. Diabetes patients with genotypes II or ID have increased plasma fibrinogen in the presence of albuminuria.     

Polymorphisms of the angiotensin-converting-enzyme gene in subjects who die from coronary heart disease

It has been shown that myocardial infarction sur vivors aremore likely to carry an insertion/deletion polymorphism (I/D)of the angiotensin-converting enzyme (ACE) gene than age-matchedpopulation controls. To test whether the association with coronary risk had been under-estimated, the frequency of the ACElID was studied in 213 fatal cases of definite and possiblemyocardial infarction which came to autopsy in the Belfast MONICAProject area. In comparison to controls from the same population,the autopsy cases had an increased frequency of the ACE D allele(p<0.02). The overall odds ratios were 2.2 for DD vs. II,and 1.8 for ID vs II (test for trend p=0.01). The findings bearout the hypothesis that the ACE l/D polymorphism is a risk factorfor fatal myocardial infarction and sudden cardiac death.     

Polymorphism of the angiotensin-converting enzyme gene affects the outcome of acute respiratory distress syndrome

OBJECTIVE: There has been increasing evidence that angiotensin II may play an important role in the pathogenesis and in the evolution of acute lung injury. It was therefore hypothesized that polymorphisms of the angiotensin-converting enzyme gene affects the risk and outcome of acute respiratory distress syndrome (ARDS). DESIGN: Prospective, observational study. PATIENTS AND SETTINGS: The ARDS group consisted of 101 patients treated at the medical intensive care unit; the control groups consisted of 138 "at-risk" patients treated at the medical intensive care unit due to acute respiratory failure but did not meet the ARDS criteria throughout the hospital course, and 210 non-at-risk subjects. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: The ARDS patients and control subjects were genotyped for the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme gene. Association of the polymorphism and the risk and the outcome of ARDS was analyzed. There was no significant difference in the frequencies of the genotypes between the ARDS, at-risk, and non-at-risk groups. The 28-day mortality rates were significantly different between the three angiotensin-converting enzyme genotypes (42%, 65%, and 75% for II, ID, and DD, respectively; p = .036). Survival analysis showed that the II genotype favorably affected 28-day survival (hazard ratio, 0.46; 95% confidence interval, 0.26-0.81; p = .007), whereas ARDS caused by hospital-acquired pneumonia had a negative effect (hazard ratio, 2.34; 95% confidence interval, 1.25-4.40; p = .008). The II genotype (hazard ratio, 0.53; 95% confidence interval, 0.32-0.87; p = .012) and ARDS caused by hospital-acquired pneumonia (hazard ratio, 2.13; 95% confidence interval, 1.24-3.68; p = .006) were also significant prognostic factors for the in-hospital mortality. CONCLUSIONS: The angiotensin-converting enzyme I/D polymorphism is a significant prognostic factor for the outcome of ARDS. Patients with the II genotype have a significantly better chance of survival. This study did not show an increased risk for ARDS in Chinese patients with the D allele.     

蒙古族人群血管紧张素转换酶基因多态性与高血压的关系

背景有关血管紧张素转换酶基因多态性与高血压关系的研究已有报道,但在蒙古族人群中尚不十分清楚.蒙古族是高血压患病率较高的民族,因此有必要探讨蒙古族人群中血管紧张素转换酶基因多态性与高血压的关系.目的探讨蒙古族人群血管紧张素转换酶基因多态性与高血压的关系.设计采用现况调查的方法.地点和对象选择内蒙古自治区通辽市科左后旗朝鲁吐苏木作为本研究现场,所有研究对象均为在此长期居住的蒙古族居民.共获得有高血压家族史的高血压者51例、血压正常者32例和没有高血压家族史的高血压者64例、血压正常者85例.干预应用聚合酶链式反应检测血管紧张素转换酶基因的插入/缺失多态性.主要观察指标血管紧张素转换酶多态性基因型频率和I、D等位基因频率.结果血管紧张素转换酶基因的三种基因型(II,ID,DD)在4组人群间的分布差异无显著性意义(P＞0.1).在4组人群中均表现出ID基因型频率最高,其次为Ⅱ基因型,DD基因型频率最低.I,D等位基因在4组人群间的分布也差异无显著性意义(P＞0.1).在4组人群中I等位基因频率均高于D等位基因频率.结论血管紧张素转换酶基因I/D多态性与蒙古族高血压的发生无关联.     

血管紧张素转换酶及血管紧张素Ⅱ1型受体基因多态性与乙型肝炎肝硬化的关系

目的研究血管紧张素转换酶（angiotensin-converting enzyme,ACE）及血管紧张素Ⅱ1型受体（angiotensin Ⅱ type 1 receptor,AT1R）基因多态性与乙型肝炎肝硬化之间的关联及其在乙型肝炎肝硬化的发生、发展中的作用。方法采用聚合酶链反应（polymerase chain reaction,PCR）及限制性片段长度多态性分析（restriction fragment length polymorphism,RFLP）检测技术,对115例乙型肝炎肝硬化患者和136例正常人群中的ACE（第16个intronI／D基因）ATlR（3＇-U TR 1166A／C）的基因多态性分布进行了检测。结果在ACE intron I／D基因多态性中各基因型在乙型肝炎肝硬化患者与正常人群中的差异无统计学意义（P〉0．05）;在乙型肝炎肝硬化患者中ACEI／D基因型的分布在有无腹水组间的差异有统计学意义,有腹水组ACED／D基因型的频率高于无腹水组（27．8％VS11．6％,Pd0．05）,两组ACE的D基因频率分布差异有统计学意义（47．2％VS31．4％,P〈0．05）;在乙型肝炎肝硬化患者中随着Child-Pauph分级的增高D／D基因型的比例逐渐增大（P〈0．05）;A、B、C3级中D基因频率分布差异有统计学意义（Pd0．05）。AT1R 1166A／C基因多态性在乙型肝炎肝硬化患者和正常人群中的差异无统计学意义（P〉0．05）。结论ACE的intron D／D基因型对于乙型肝炎肝硬化是不利因素,它可能与肝硬化患者腹水的形成相关,并可促进肝硬化的进展;而AT1R的1166A／C基因位点的变异尚未显示其与肝硬化有关。     

汉族人群血管紧张素转换酶基因插入/缺失(I/D)的遗传多态性

背景:血管紧张素转换酶是肾素-血管紧张素-醛固酮系统的重要组成部分,血管紧张素转换酶基因第16内含子内存在一个287bp的Alu序列的插入/缺失(I/D)多态性,与心血管疾病、IgA肾病等疾病的发生具有一定的相关性。目的:分析汉族人群血管紧张素转换酶基因插入/缺失(I/D)多态性的分布,并与已知的其他种族人群进行比较。设计:以健康汉族人为观察对象的观察性实验。单位:江苏省临床免疫学重点实验室,苏州大学附属第一医院检验科,江苏大学医学技术学院检验系。对象:受检者为2005-12/2006-01苏州大学附属第一医院门诊健康体检者241名,男152名,女89名,平均年龄(27±8)岁,均为无血缘关系的苏州地区汉族人,经临床及实验室检查确认排除肝、肾、内分泌、心脑血管疾病。方法:应用聚合酶链反应检测了241名汉族健康体检者血管紧张素转换酶基因I/D多态性等位基因的基因型,并采用荧光标记末端终止法对基因型为D/D、I/I的PCR纯化产物进行DNA测序确认。主要观察指标:血管紧张素转换酶基因I/D基因型,等位基因频率以及与其他种族人群的比较。结果:241名受检者全部进入结果分析。①血管紧张素转换酶的基因型表现为缺失纯合子(DD)、插入纯合子(II)以及缺失和插入杂合子(DI),等位基因D较等位基因Ⅰ缺失一段287bp的核苷酸,即Alu序列。②II,ID,DD基因型频率分别为46.1%,41.5%,12.4%;等位基因I,D频率分别为66.8%,33.2%。③日本人与汉族人群血管紧张素转换酶基因型分布相似,均以II型最常见,DD型最少;欧美人群以ID居多,II型较少。汉族人群与日本人及欧美人群血管紧张素转换酶基因型频率的分布具有种族差异性。与其他各民族人群比较,汉族人群等位基因I显著高于上述各民族(χ2=105.55,P<0.01),等位基因D明显较低(χ2=87.54,P<0.01)。结论:血管紧张素转换酶基因多态性具有种族差异性。了解不同种族人群间血管紧张素转换酶基因多态性的遗传特点,是研究血管紧张素转换酶基因I/D多态性与疾病相关性的基础和前提。     

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。       

Angiotensin converting enzyme gene polymorphism and glomerular filtration rate changes in type 2 diabetic patients

It has been suggested that an insertion/deletion (I/D) polymorphism in intron 16 of the angiotensin-converting enzyme (ACE) gene may be associated with diabetic nephropathy The aim of this study was to investigate whether an association exists between ACE I/D polymorphism and glomerular filtration rate (GFR) in type 2 diabetes mellitus. A total of 128 type 2 diabetic patients were included in the study with the following ACE genotype distribution: DD 40, ID 58,11 30. I/D polymorphism was determined by polymerase chain reaction (PCR). Mean GFR was not statistically different according to ACE genotype (DD: 89.9 +/- 28.1 ml/min, ID: 99.5 +/- 25.1 ml/min, II: 96.6 +/- 19.6 ml/min). There was no significant difference in genotype distribution in normo-, micro- and macroalbuminuric patients (DD:ID:II [%], normo- 35:46:19, micro-28:55:17, macro- 31:55:14). ACE I/D polymorphism does not seem to be associated with GFR in type 2 diabetic patients.     

The link between angiotensin-converting enzyme genotype and pulmonary artery pressure in patients with COPD

OBJECTIVE: The insertion (I)/deletion (D) polymorphism of the angiotensin-converting enzyme (ACE) gene has been associated with an increased risk of cardiovascular diseases. In patients with primary pulmonary hypertension, the homozygous ACE DD genotype is more prevalent than the non-DD genotype. However, the relationship of ACE gene polymorphism to secondary pulmonary hypertension remains unclear, and ethnicity may be one of the factors that can modulate the effects of ACE genotypes reported in different studies. We hypothesized that in patients with chronic obstructive pulmonary disease (COPD) the presence of the D allele in the ACE gene polymorphism is associated with increased pulmonary artery pressure (Ppa). PATIENTS AND METHODS: Bodyplethysmography was used to assess lung function in 66 consecutive patients with COPD; pulmonary artery pressures were determined using echocardiography. ACE gene I/D polymorphism was identified with the polymerase chain reaction. 118 healthy persons served as the control group. All patients and controls were Caucasian. Genotype II was identified in 15 patients with COPD, genotype ID in 31 and genotype DD in 20. In the control group, genotype II was identified in 19 persons, genotype ID in 68 and genotype DD in 31. The distribution of ACE gene polymorphism did not differ between patients and the control group. RESULTS: In patients with COPD, no differences were seen between the three genotype groups in mean age, smoking history, hemoglobin concentrations or ventilometric or blood gas variables. Both systolic and mean Ppa differed significantly between the II, ID and DD groups (Systolic Ppa: 24.4 +/- 2.2 versus 31.3 +/- 2.5 and 36.7 +/- 3.9 mm Hg, respectively, ANOVA, p < 0.05; Mean Ppa: 13.0 +/- 1.5 versus 17.5 +/- 1.4 and 21.2 +/- 2.8 mm Hg, respectively, ANOVA, p < 0.05). In multiple linear regression analysis, the I/D ACE gene polymorphism (p < 0.05), SaO2 (p < 0.05) and the duration of COPD (p < 0.02) were independent predictors of systolic and mean Ppa. CONCLUSION: The results of the study suggest that I/D ACE gene polymorphism is linked to pulmonary artery pressure in Caucasian patients with COPD.     

南疆塔吉克族和维吾尔族人群血管紧张素转换酶（ACE）基因多态性分析

目的研究南疆地区塔吉克族和维吾尔族人群血管紧张素转换酶（ACE）基因插入/缺失（I/D）多态性分布情况。方法采用聚合酶链式反应（PCR）分别对88例南疆塔吉克族和106例南疆维吾尔族正常人群样本的ACE基因I/D多态性进行检测,分类计数进行统计分析。结果 ACE基因3种基因型频率分别为：南疆塔吉克族DD型25%,ID型17.05%,Ⅱ型57.95%,D和等位基因频率分别为33.53%和66.48%;南疆维吾尔族DD型42.45%,ID型23.58%,Ⅱ型33.96%,D和I等位基因频率分别为54.24%和45.75%;结论南疆两个不同民族人群ACE因多态性的分布与性别无关;南疆塔吉克族DD型及D等位基因频率低于南疆维吾尔族;南疆塔吉克族和南疆维吾尔族Ⅱ型频率均高于欧美人和日本人。     

血管紧张素Ⅰ转换酶基因多态性与妊娠高血压综合征的关系

目的:探讨血管紧张素Ⅰ转换酶(ACE)基因多态性与妊娠高血压综合征(妊高征)发病的关系。方法:应用多引物PCR技术检测120例妊高征患者(妊高征组,其中轻度29例、中度31例、重度60例)及110例正常孕妇(对照组)的ACE基因多态性。结果:妊高征组孕妇ACE基因中的II、ID、DD基因型频率分别为20.8%、37.5%、41.7%。对照组孕妇ACE基因中的II、ID、DD基因型频率分别为44.5%、29.1%、26.4%。两组孕妇的DD基因型及D等位基因频率比较,差异有显著性(P<0.05)。妊高征组轻度与重度患者的DD基因型比较,差异有显著性(P<0.05)。回归分析表明,DD基因型及D等位基因与妊高征发病相关。结论:ACE基因中DD基因型是妊高征的易感基因,II基因型是妊高征的保护基因。     

The angiotensin-converting enzyme insertion/deletion polymorphism is associated with phagocytic NADPH oxidase-dependent superoxide generation: potential implication in hypertension

The objective of the present study was to analyse the influence of the ACE (angiotensin-converting enzyme) gene I/D (insertion/deletion) polymorphism on NADPH oxidase-dependent O(2)(*-) (superoxide radical) production, and to investigate the clinical implication of this association in hypertensive subjects. A case-control study was performed in a random sample of the general population composed of 189 normotensive subjects and 223 hypertensive subjects. The ACE polymorphism was determined by PCR. NADPH oxidase-dependent O(2)(*-) production was quantified in phagocytic cells by chemiluminescence. MMP-9 (matrix metalloproteinase-9), a marker of atherosclerosis previously reported to be associated with NADPH oxidase overactivity, was quantified by ELISA in plasma samples. The distribution of genotypes was in Hardy-Weinberg equilibrium. The I/D polymorphism was not associated with hypertension. NADPH oxidase-dependent O(2)(*-) production was significantly higher in D/D (deletion/deletion) than in I/I (insertion/insertion) and I/D, both in normotensive and hypertensive subjects. Interestingly, plasma levels of angiotensin II were significantly higher in D/D than in I/I and I/D, both in normotensive and hypertensive subjects. Plasma levels of MMP-9 and systolic blood pressure values were significantly higher in D/D than in I/I and I/D hypertensive subjects, whereas no differences were found among genotypes in normotensive subjects. Interestingly, NADPH oxidase-dependent O(2)(*-) production positively associated with plasma MMP-9 levels in hypertensive subjects, which remained significant after adjustment for age and gender. In conclusion, in the present study we have reported for the first time an association of the D/D genotype of the ACE I/D polymorphism with phagocytic NADPH oxidase-mediated O(2)(*-) overproduction. Within the group of hypertensive patients, D/D cases also associated with increased blood pressure values and with enhanced plasma levels of MMP-9.     

No association found between the insertion/deletion of a 287-bp alu repeat sequence within intron 16 of the angiotensin-I-converting enzyme (ACE) gene in Mexican patients and binary restenosis after coronary stenting

BACKGROUND: It has been suggested that the incidence of coronary restenosis after a percutaneous coronary intervention is much higher in patients with a 287-bp alu repeat sequence within intron 16 of the angiotensin-I-converting enzyme (ACE) gene (deletion allele) than in others, but published studies are conflicting. METHODS: The presence (insertion) or absence (deletion) of a 287-bp alu repeat sequence within intron 16 of the ACE gene (I/D polymorphism) was analyzed by polymerase chain reaction in a group of 168 patients with coronary artery disease who underwent coronary artery stenting. Basal and procedure coronary angiographies were analyzed searching for angiographic predictors of restenosis and follow-up angiography was analyzed looking for binary restenosis. RESULTS: Distribution of angiotensin converting enzyme I/D polymorphisms was similar in patients with and without restenosis. Similar results were observed when the analysis was made considering the type of stent implanted. On the other hand, the whole group of coronary artery disease patients showed increased frequencies of the D allele (p=0.00001, OR=2.17, 95% CI=1.49-3.16) and ID genotype (p=0.0002, OR=2.58, 95%CI=1.49-4.47) when compared to healthy controls. CONCLUSIONS: Genetic variations of the ACE gene could be a genetic factor related to coronary artery disease in the Mexican mixed racial ancestry individuals, but do not support its role as a risk factor for developing restenosis after coronary stenting.