Association of Polymorphisms in Angiotensin-converting Enzyme and Type 1 Angiotensin Ⅱ Receptor Genes with Coronary Heart Disease and the Severity of Coronary Artery Stenosis

To explore the relation of angiotensin-converting enzyme （ACE） and angiotensin Ⅱ type 1 receptor （AT1R） gene polymorphism with coronary heart disease （CHD） and the severity of coronary artery stenosis, 130 CHD patients who underwent coronary angiography were examined for the number of affected coronary vessels （≥75% stenosis） and coronary Jeopardy score. The insertion/deletion of ACE gene polymorphism and AT1R gene polymorphism （an A→C transversion at nucleotide position 1166） were detected by using polymerase chain reaction （PCR） and restriction fragment length polymorphism （RFLP） in CHD patients and 90 healthy serving as controls. The resuits showed that DD genotype and of ACE were more frequent in CHD patients than that in control group （38.5% vs 14.4%, P〈0.001）. The frequency of the ATIR A/C genotypes did not differ between the patients and the controls （10% vs 13.1%, P〉0.05）. The relative risk associated with the ACE-DD was increased by AT1R-AC genotype. Neither the number of affected coronary vessels nor the coronary score differed among the ACE I/D genotypes （P〉0.05）. But the number of affected coronary vessels and the coronary score were significantly greater in the patients with the AT1R-AC genotype than in those with the AA genotype （P〈0.05）. In conclusion, DD genotype may be risk factor for CHD and MI in Chinese people, and is not responsible for the development of the coronary artery stenosis. The AT1R-C allele may increase the relative risk associated with the ACE-DD genotype, and may be involved in the development of the stenosis of coronary artery.

Angiotensin-converting enzyme and bradykinin gene polymorphisms and cough:A meta-analysis

AIM:To evaluate the association between genetic polymorphisms and angiotensin converting enzyme in-hibitor (ACEI)-related cough,and the race-or ethnicity-related difference in the prevalence of cough attributed to ACEI therapy.METHODS:We conducted a search in PubMed,EM-BASE,Cinahl,and the Cochrane Database without language limitation.A database of 11 studies on ACEI-related cough,with detailed information regarding ACE I/D or bradykinin B 2 receptor polymorphisms,was created.Eligible studies were synthesized using meta-analysis methods,including cumulative meta-analysis.A subgroup analysis was also performed using ethnicity.RESULTS:Six studies were included on ACE I/D poly-morphism (398 Caucasians,723 East Asians),and three studies were included on bradykinin B 2 receptor poly-morphism (300 East Asians).The distribution of ACE genotypes showed significant differences in the entire population (P=0.004) and in East Asians (P=0.005)but not in Caucasians (P=0.23).Allelic frequencies of ACE showed significant differences in East Asians [odds ratio (OR)=1.49 (1.11-2.02)].The meta-analysis with a random effects model showed a significant associa-tion between ACE allele I/D and ACEI-related cough [random effects (RE) OR=1.49 (1.11-2.02),P=0.009] in East Asians,but not in Caucasians [RE OR=0.90 (0.60-1.35)].The allelic frequencies of the bradykinin B 2 receptor gene were significantly different [OR=2.25 (1.42-3.57)].The distributions of the T/C genotypes of the bradykinin B 2 receptor gene were significantly dif-ferent (χ 2=8.366,P=0.015).The meta-analyses re-vealed that there was a significant association between the bradykinin B 2 receptor allele and ACEI-related cough in East Asians [RE OR=2.29 (1.42-3.69),P=0.001].CONCLUSION:ACE I/D and Bradykinin B 2 receptor polymorphisms contributed to the risk of ACEI-related cough in East Asians,but a negative association be-tween ACE I/D polymorphism and ACEI-related cough was observed in Caucasians.

Correlation of angiotensin converting enzyme gene polymorphism with perioperative myocardial protection under extracorporeal circulation

Objective:To observe the expression of angiotensin converting enzyme(ACE),angiotensinⅡ(AngⅡ),cardiac troponin 【cTnⅠ),creatine kinase isozymes(CK-MB) and muscle red protein(Myo) after cardiopulmonary bypass(CPB),and to investigate the association of polymorphisms in angiotensin converting enzyme genes and myocardial injury.Methods:Sixty-three patients suffered from rheumatic mitral stenosis and scheduled for mitral valve replacement with CPB, were randomly divided into three groups according polymorphisms in angiotensin converting enzyme genes:typeⅡ,type ID,type DD(each=21).Blood samples were withdrawn from artery before operation(T1),at the beginning of CPB(T2),30 min after CPB(T3),(T4) at the end of CPB(T5), 2 h after CPB(T6),6 h after CPB(17) to measure the expression of ACE,AngⅡ,cTnⅠ,CK-MB, Myo.Results:The level of ACE during and after CPB were significantly higher than those before CPB(P【0.05).As extension of CPB time,the expression of ACE was increased.The level of cTnⅠ, CK-MB,Myo after CPB were significantly higher than those before CPB(P【0.05).The level of cTnⅠ,CK-MB and Myo were highest at T7,T6 and T5 and T7,respectively.The level of ACE,AngⅡ,cTnⅠin patients with DD genotype was significantly higher than the ID andⅡgenotype(P【 0.05).Besides,the level of ACE,AngⅡin patients with ID genotype was significantly higher than the II(P【 0.05).Conclusions:There is certain correlation between CPB perioperative midterm ACE and cTnⅠ,Myo,CK-MB.ACE DD genotype is a susceptibility gene of the CPB perioperative myocardial injury.

Role of angiotensin converting enzyme and angiotensinogen gene polymorphisms in angiotensin converting enzyme inhibitor-mediated antiproteinuric action in type 2 diabetic nephropathy patients

AIM To investigate the role of genetic variants of angiotensin converting enzyme(ACE) and angiotensinogen(AGT) genes in the antiproteinuric efficacy of ACE inhibitor therapy in diabetic nephropathy(DN) patients.METHODS In the present study, 270 type 2 diabetes mellitus patients with nephropathy were enrolled and treated with ACE inhibitor(ramipril) and followed at 6 mo for renal function and albumin excretion by estimating serum creatinine, end stage renal disease, and albumin/creatinine ratio(ACR) in urine. Genotyping of ACE I/D and AGT M235 T polymorphisms were performed by using primer specific polymerase chain reaction(PCR) and PCR-RFLP techniques, respectively. RESULTS Forty-eight percent of DN patients(responders) benefited with respect to proteinuria from ACE inhibitor therapy at 6 mo follow-up. A significant reduction in ACR was observed after 6 mo treatment with ACE inhibitor irrespective of whether DN patients were micro-albuminuric(≥ 30 and < 300 mg/g creatinine) or macro-albuminuric(≥ 300 mg/g creatinine) at the time of enrollment. However, macro-albuminuric patients(55%) showed better response to therapy. A reduction in urinary ACR was found independent of genotypes of ACE I/D and AGT M235 T polymorphisms although macro-albuminuric patients having TT genotype showed statistically insignificant increased response(72%). CONCLUSION ACE inhibitor therapy reduced urinary ACR by ≥ 30% in 50% of DN patients and the response is independent of ACE I/D and AGT M235 T polymorphisms.

Angiotensin-converting Enzyme Gene Insertion/Deletion Polymorphism in Children with Henoch-Schonlein Purpua Nephritis

This study investigated the relationship between angiotensin-converting enzyme (ACE) gene insertion/deletion polymorphism and the occurrence, severity, prognosis of HSPN. The polymorphism of ACE gene in 103 HSPN cases and 100 healthy children was studied by using the polymerase chain reactions (PCR). Its relation to the clinical manifestation, pathological classification and prognosis of HSPN was analyzed accordingly. The results showed that: (1) there was a significantly higher frequency for DD genotype in HSPN children (P<0.01); (2) DD genotype was more frequently seen in HSPN children with gross hematuria and massive proteinuria (P<0.05), while DI genotype was more common in HSPN children group with renal insufficiency (P<0.05); (3) although mesangial proliferative lesion was most frequently observed in 21 biopsied HSPN children, and DD genotype frequency was still higher in children with severe pathology (Class Ⅲ Ⅳ); (4)II genotype was significantly frequent in HSPN children with complete remission in the follow-up of 32 HSPN children. It was concluded that the deletion allele of ACE gene might play a role, at least to some extent, in the occurrence, deterioration and progression in juvenile HSPN.

POLYMORPHISM OF ANGIOTENSIN CONVERTING ENZYME GENE AND GENETIC SUSCEPTIBILITY TO ASTHMA WITH FAMILIAL AGGREGATION

Angiotensin converting enzyme (ACE) plays a key role in the metabolism of angiotensin Ⅱ (AT Ⅱ) and inactivation of bradykinins and tachykinins, which are potent bronchialconstrictors and mediators of inflammation asthma, and ACE is heavily expressed in the lungs. An insertion deletion (D/I) polymorphism of ACE gene has been shown to be associated with levels of ACE. We investigate whether the polymorphism of ACE gene is associated with asthma and bronchial responsiveness. Methods. A case control study was carried out in 50 asthmatics, 7 families with at least 2 asthmatic individuals, and 50 healthy subjects. The insertion/deletion (I/D) polymorphism of ACE gene was amplified by polymerase chain reaction (PCR). Methacholine brocho provocation and pulmonary function tests were performed in all asthmatics. Results. There was an higher gene frequency of DD genotype of ACE gene in asthmatic subjects and families individuals compared with healthy subjects (46%, 53% vs 16%, P<0 05; odd ratio 4 98). Anhigher prevalence of DD genotype of ACE was in patients with bronchial hyperresposiveness (BHR) (67%vs 33%, P<0 05; odd ratio 3 8). Accordingly, the mean values of FEV 1% and FEV 1/FVC were higher in asthmatics carrying non DD alleles than patients with DD genotype (73 78% vs 56 56%, P<0 05; 79 19% vs 69 29%, P<0 05, respectively). Conclusion. These results suggested that DD allele of ACE genotype was significantly involved in genetic susceptibility to asthma. DD genotype of ACE might be a risk factor for the degree of airway obstruction, it could also be implicated in pathogenesis of bronchial hyperresponsiveness.

Association of Angiotensin Converting Enzyme Gene I/D Polymorphism With Type 2 Diabetes Mellitus

Objective To investigate the association of angiotensin converting enzyme （ACE） gene insertion/deletion （I/D） polymorphism with type 2 diabetes mellitus （T2DM）. Methods Two hundred and nine patients with T2DM diagnosed based on the criteria for diabetes mellitus in 1999 by WHO and 221 controls were recruited from general population of Dongcheng District in Beijing. All subjects were genotyped for the I/D polymorphism of ACE gene by PCR-fragment length polymorphism （FLP） assay. Blood pressure, levels of plasma glucose, lipids and serum insulin were determined. Body mass index （BMI）, waist-trip ratio （WHR） and homeostasis model assessment-insulin resistance index （HOMA-IR） were calculated. Results The genotype frequencies for ACE genes DD, ID, and II were 19.1%, 42.1%, and 38.8% in patients, respectively, and 9.6%, 49.4%, and 41.0% in controls, respectively. The ACE DD genotype frequency was significantly higher in patients than in controls （χ^2=7.61, P=0.022）. Multivariate logistic regression analysis showed that the ACE DD genotype was a risk factor for T2DM, with the OR of 2.35 （95% CI 1.17-4.71） adjusted for age, sex, BMI, WHR, blood pressure, and serum cholesterol levels. Conclusion The ACE DD genotype is associated with the increased susceptibility to type 2 diabetes mellitus.

Angiotensin-converting enzyme gene polymorphism and middle cerebral artery stenosis in a Chinese Han population

The angiotensin-converting enzyme gene is a candidate gene of stroke. The present study involved 62 healthy volunteers and 148 patients with middle cerebral artery stenosis as confirmed by brain color ultrasound from a Han population in North China, and determined the peripheral blood angiotensin-converting enzyme genotype using PCR-restriction fragment length polymorphism analysis. The results showed that the frequencies of the DD genotype and D allele were increased in patients with middle cerebral artery stenosis, but the difference was not statistically significant compared with healthy controls. The findings of this study on the relationship between stroke genes and middle cerebral artery stenosis indicate no significant correlation between the frequencies of the DO genotype and D allele of angiotensin-converting enzyme and middle cerebral artery stenosis in this Han population from North China. In the future, studies will be carried out to investigate correlations between multiple stroke candidate gene synergy and middle cerebral artery stenosis to provide a foundation for the development of gene therapy.

Plasma Levels of Angiotensin-Converting Enzymes 1 and 2 and <i>AGTR</i>2 (T1247G and A5235G) Gene Polymorphisms Are Associated to Breast Cancer Progression

Background: Breast cancer is the most common type of cancer among women. Diagnosed and treated timely, patients may have good prognostics. In Brazil, in 2012, the estimate of new cases was 52,680 and the number of registered deaths in 2012 was 12,852. The Renin-Angiotensin System (RAS) is known for its role in arterial hypertension and in other cardiovascular diseases. Angiotensin-Converting Enzyme 2 (ACE2) is the key to Ang-(1-7) formation, and counterbalances the ACE1/AngII/AGTR1 axis actions. RAS components have complex interactions with different tissues and their actions are not restricted to the cardiovascular system. Recently, the RAS has been associated with different types of cancers and in particular with gynecological cancers. Objectives: Our aim is to investigate possible associations between allelic distribution of two genetic polymorphisms in the AGTR2 receptor with ACEs 1 and 2 plasma levels among women with breast cancer. Patients and Methods: Patients with breast cancer were genotyped for two polymorphisms of the AGTR2 (T1247G and A5235G). Genotyping assays (TaqMan) were performed with genomic DNA extracted from blood cells. ACEs plasma level measurements were conducted in women from the breast-cancer group (N = 53). ACEs were measured in the plasma of these patients using ELISA kits. Results: SNPs genotype distribution is correlated with ACEs plasma levels. ACEs plasma levels are also correlated with clinical variables and ACE2 high levels are associated with better prognostics. Conclusions: Changes in circulating levels of ECA1/AngII ECA2/ Ang-(1-7) determine the magnitude of the inflammatory response that an individual can trigger and the variation in ACE 1 and 2 plasma level measurements in the blood of breast cancer patients suggests an association with the process of mammary carcinogenesis. Thus, the RAS may be associated with the process of mammary carcinogenesis by both genotypic variations of RAS components and by circulating levels of ACEs.

Left ventricular hypertrophy in relation to systolic blood pressure and the angiotensin converting enzyme I/D polymorphism in Chinese

Objective There is little population-based data on the prevalence and the environmental or genetic determinants of left ventricular hypertrophy （LVH） in China. The purpose of this paper is to study LVH in relation to systolic blood pressure and the angiotensin converting enzyme （ACE） insertion/deletion（I/D） polymorphism in Chinese. Methods We recorded 12- lead ECG （CardioSoft, v4.2） in 1365 residents in the Jingning County, Zhejiang Province, China. LVH was defined according to the gender-specific Sokolow-Lyon and Cornell product ECG criteria. Results Regardless of whether the Sokolow-Lyon or Cornell product ECG criteria was used, the prevalence of LVH （20.7% and 4.8%, respectively） significantly （P〈0.0001） increased with male gender （odds ratio [OR] 2.33 and 7.15） and systolic blood pressure （per 10 mm Hg increase, OR 1.46 and 1.33）. If the Sokolow-Lyon criteria was used, the prevalence of LVH was also influenced by alcohol intake （OR 1.44, P=-0.03） and body mass index （OR 0.83, P=0.0005）. The association between the Sokolow-Lyon voltage amplitude and the ACE I/D polymorphism was dependent on antihypertensive therapy （P=0.01）. In 1262 untreated subjects, but not 103 patients on antihypertensive medication, the ACE DD compared with II subjects had significantly higher Sokolow-Lyon voltage amplitudes （29.8：-0.6 vs. 28.0-3：0.5 mV, P=-0.02） and higher risk of LVH （OR 1.74, 95% CI： 1.12-2.69, P=-0.01）. Conclusion LVH is prevalent in Chinese, and is associated with systolic blood pressure and the ACE D allele. The genetic association might be modulated by antihypertensive therapy（J Geriatr Cardio12009; 6：131-136）.

Interaction and Relationship Between Angiotensin ConvertingEnzyme Gene and Environmental Factors Predisposing toEssential Hypertension in MongolianPopulation of China

Objective To investigate the association of specific functional gene ACE (I/D) variants of the renin-angiotensin system with essential hypertension (EH) and interaction between ACE (I/D) gene and risk factors for EH in a genetically homogenous Mongolia rural population of China. Methods Individuals (n=1099) were recruited from general population of Kezuohouqi Banner in Inner Mongolian Autonomous Region. Results The association was found between ACE genotype DD plus ID and EH, with an interaction between ACE genotype DD plus ID and cigarette smoking in an additive model. Cigarette smoking index and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 7.10 to 1.16. Interaction between ACE genotype DD plus ID and alcohol drinking on EH appeared an additive model. Alcohol drinking index and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 1.66 to 1.09. BMI and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 6.15 to 2.49. Interactions between ACE genotype and WHR on EH showed a multiplicative model. In a short, there was an interaction between ACE gene and cigarette smoking, alcohol drinking and BMI on EH, especially in a low dose-exposure effect Conclusion It is important for individuals who carry ACE D allele gene to prevent EH, and furthermore, to prevent and control coronary heart disease, in a view of population-based prevention.

Study of angiotensin converting enzyme and genotype among Egyptian preeclampsia patients

Preeclampsia is a frequent disorder with reported incidence in pregnancies. In Egypt, it complicates 6%-8% of pregnancies and reaches 15% in referral centers. The renin-angiotensin system activation during the early stages of Preeclampsia proved to be a direct cause. Women carrying the D allele of the ACE-I/D polymorphism have higher measures of uterine artery resistance, which is a marker for development of intrauterine growth retardation and preeclampsia. The maternal syndrome of preeclampsia (PE) during the latter half of pregnancy is believed to result from impaired placentation in early gestation and a failure to develop low resistance uteroplacental circulation. Aim: The aim of this study was to evaluate the association with angiotensin converting enzyme gene polymorphism and changes in its enzyme serum level in preeclamptic patients compared to non preeclamptic control group together with studying the changes in umbilical artery and uterine artery Doppler. Subjects: The study was conducted on 180 pregnant women allocated into two groups having the same inclusion and exclusion criteria except for hypertension and proteinuria;each group comprised of 90 pregnant women with matched age. Methods: Doppler study of umbilical and uterine arteries and the detection of Angiotensin converting gene polymorphism by PCR with Estimation of serum ACE in serum by ELISA technique. Results: The distribution of the ACE-I/D genotypes and allelic frequencies in the present study of polymorphism was 37.8% for the DD, 48.9% for the ID, 13.3% for the II in preeclampsia group while it was 33.3% for the DD, 46.7% for the ID, and 20% for the II in the control group. There was no significant difference between cases and controls regarding the cumulative D effect. Conclusions: No existence of a relation between preeclampsia and ACE gene polymorphism considering different modes of inheritance whether is dominance or recessiveness. No effect of ACE gene polymorphism is on ACE serum level. Positive correlation between ACE gene polymorphism and the uterine artery Doppler changes gives strong evidence that ACE gene may have a role in the histopathological changes taking place in these vessels, therefore affecting maternal prognosis. It is unclear to explain this mismatched ACE genetic influence on the incidence of preeclampsia, but the multifactorial pathogenesis of the development and complication in preeclampsia and also physician’s intervention may contribute to the pregnancy outcome. Recommendations: International collaborations, particularly among countries with a high incidence of preeclampsia, may help to include participants with different cultural and genetic backgrounds, which can provide further insight into the etiology of the disease both genetic and environmental.

Association of angiotensin-converting enzyme gene insertion/deletion polymorphism with the clinico-pathological manifestations in immunoglobulin A nephropathy patients

Objective To investigate the relationship between angiotensin converting enzyme (ACE) gene insertion/deletion polymorphism and the clinico pathological manifestations in patients with immunoglobulin nephropathy (IgAN). Methods A flanking primer pair and an insertion specific primer pair were used to perform two polymerase chain reactions so as to analyse the insertion/deletion polymorphism of ACE gene. Results There was a significantly higher genotype fre quency for DD genotype in IgAN patients. The frequencies for DD genotype were also higher in those patients with hypertension and/or heavy proteinuria and/or severe glomerular sclerosis (P<0.05). Conclusions We observed a significant association of the deletion polymorphism of ACE gene with renal insufficiency, hypertension and severe glomerular lesions at biopsy. The deletion allele may play a role, at least to some extent, in the deterioration and progression in IgA nephropathy.

Polymorphisms of angiotensin-converting enzyme 2 gene associated with magnitude of left ventricular hypertrophy in male patients with hypertrophic cardiomyopathy

Background Even carrying an identical gene mutation, inter- and intra-family variations have been noticed worldwide in the presence and the severity of left ventricular hypertrophy and sudden death in patients with hypertrophic cardiomyopathy （HCM）. Modifier genes may contribute to the diversity. Angiotensin-converting enzyme 2 （ACE2） gene has been established to be associated with parameters of left ventricular hypertrophy in community based male subjects. The objective of the present study was to investigate the association of ACE2 gene polymorphisms with the phenotype of HCM. Methods A total of 261 consecutive HCM patients and 609 healthy controls were enrolled into this study. The polymorphism of rs2106809 and rs6632677 were genotyped by polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） and confirmed by sequencing. Logistic regression model and multivariate analysis were used to determine the odds ratio （OR） and 95% confidence intervals （CO of variations of ACE2 for HCM. Results The T allele of rs2106809 and C allele of rs6632677 conferred increasing risk for HCM （OR 1.34, 95%C/ 1.01-1.77, P=0.04; OR 1.11, 95%C/ 1.03-1.21, P=0.002, respectively）, and the 2 single nucleotide polymorphisms （SNPs） were in strong linkage disequilibrium （LD）, the TC haplotype was independently associated with a higher OR for HCM （OR=1.59, 95%C/1.21-1.87） after adjusted for conventional risk factors. And the risk alleles were associated with thicker interventricular septal thickness of HCM （（20.0±6.3） mm vs （17.9±5.5） mm, P=0.03 and （21.3±5.9） mm vs （17.9±5.8） mm, P=0.04, respectively）. No association was found between the two polymorphisms with female patients with HCM. Conclusion Minor alleles of ACE2 gene might be the genetic modifier for the magnitude of left ventricular hypertrophy in male patients with HCM.

Association of angiotensin converting enzyme gene insertion/deletion polymorphism with essential hypertension in south Indian population

Genetic,environmental and demographic factors contribute to the development of essential hypertension.Genetic polymorphism of Rennin-angiotensin-aldosterone system(RAAS)has been extensively studied to determine the genetic susceptibility to hypertension.The insertion/deletion(I/D)angiotensin converting enzyme(ACE)polymorphism has been established as a cardiovascular risk factor in some population,but its association with essential hypertension is controversial.This study sought to determine the association of I/D polymorphism of the ACE gene in south Indian essential hypertensive subjects.A total of 208 clinically diagnosed essential hypertensive patients without any associated diseases and 220 healthy control subjects were included in this study.Distribution and allelic frequency of Insertion(I)and Deletion(D)polymorphism at the 287 base pair Alu repeat sequence in the intron 16 of ACE gene were analyzed.The distribution of II,ID,DD genotypes of ACE gene was 28.3%,32.6%and 38.9%respectively in essential hypertensive patients and to 53.6%,26.3%and 20%in controls.The allele frequency for D allele is 0.58 in essential hypertension as compared to 0.34 of control subjects.The genotype and allele frequency of ACE gene polymorphism is significantly differed in patients when compared to controls.In conclusion,the I/D polymorphism of ACE gene is associated with Indian essential hypertension.

Carotid remodeling of hypertensive subjects and polymorphism of the angiotensin-converting enzyme gene

Background This study was designed to investigate the relationships between changes in the structure and function of carotid arteries and angiotensin converting enzyme (ACE) gene polymorphism in Chinese hypertensive subjects. Methods Multiplex polymerase chain reaction amplification was used to evaluate the ACE gene insertion/deletion (I/D) polymorphism. High-resolution B-mode ultrasound examinations were performed to detect parameters of carotid artery remodeling. Results Intima-media thickness (IMT) was significantly different among the DD, ID and II genotypes of ACE (DD>ID>II, P <0.05). Carotid internal diameter,distensibility and stiffness were similar among the DD,ID and II genotypes of ACE ( P >0.05) in hypertensive subjects. The frequency of the DD gene and D allele of ACE were higher in patients with thickening carotid than in patients with normal carotid (70.4% vs 24.1%,and 79.5% vs 40.5%,respectively, P <0.001). In multiple stepwise regression analysis,independent risk factors for increased carotid IMT in hypertensive subjects were ACE genotypes ( P <0.001),age ( P <0.001) and carotid internal diameter ( P =0.032). Moreover,triglycerides and total cholesterol were higher in patients with the DD genotype than in those with the II genotype ( P <0.05). Conclusions The I/D polymorphism of the ACE gene was related to IMT,but not to internal diameter,distensibility and stiffness of the carotid in Chinese hypertensive subjects. ACE gene polymorphism was a main risk factor for increased carotid IMT. These results may imply that there is a link between lipid metabolism and ACE genotype polymorphism in Chinese hypertensive subjects.

Interferon Regulatory Factor 5 and Renin-Angiotensin-Aldosterone System Polymorphisms in Coronary Artery Disease: An Overview of Experimental and Clinical Studies

Heart diseases are the main cause of mortality in Mexico, being coronary heart disease the most frequent in the country. Its high prevalence makes important the study of the pathophysiology and the search for prognostic factors. Different genes and polymorphisms promote atherogenesis and coronary artery disease, they affect inflammatory and vascular pathological processes. Interferon regulatory factor 5 (IRF5) is associated with coronary heart disease, it promotes chronic inflammation and cytokines release;it could trigger immune reactions and its activating receptors express in the vascular endothelium. Besides, polymorphisms in the renin-angiotensin-aldosterone system (RAAS) are implied with coronary disease, they are found in angiotensinogen (AGT), angiotensin II type 1 receptor (AT1R), angiotensin II type 2 receptor (AT2R), and angiotensin-converting enzyme (ACE) genes. These genetic polymorphisms are associated with a prothrombotic state, endothelial dysfunction, and immune activation. Multiple experimental studies showed that chronic activation of RAAS and chronic expression of IRF5 generates an environment prone to the development of atherosclerosis, and autoimmune and cardiovascular diseases. Studying these specific genes and their relationship with coronary heart disease will allow a better understanding of the pathological process and possibly the quest for new treatments.

Angiotensin Ⅰ-converting enzyme gene poly morphism in Chinese patientswith obstructive sleep apnea syndrome

Objective To investigate the relationship of an insertion/deletion (I/D) polymorphism of the angiotension converting enzyme (ACE) gene to obstructive sleep apnea syndrome (OSAS) patients and the control subjects.Methods Genomic DNA was extracted from blood samples and amplified by polymerase chain reaction (PCR). PCR primers flanked the polymorphic region in intro 16 of the ACE gene. Results OSAS patients had significantly higher frequencies of I/I genotype and insertion allele of the ACE gene as compared with the control subjects in Chinese population. The OSAS patients with I/I genotype had significantly longer apnea time, lower minimum SaO2 and greater AHI than the OSAS patients with I/D genotype. Conclusion These results indicate that the I/I genotype and I allele are a risk factor for OSAS in Chinese.

Angiotensin-converting enzyme gene I/D genotype affected metoprolol-induced reduction in 24-hour average heart rate

Background Genetic factors can influence antihypertensive response to metoprolol, and many studies focused on the relationship between the genotype in β1-adrenergic receptor and blood pressure （BP）, little was known about the association of angiotensin-converting enzyme （ACE） genotype with the therapeutic result of metoprolol. The present study aimed to investigate whether the ACE gene insertion （I） / deletion （D） polymorphism is related to the response to metoprolol in Chinese Han hypertensive patients, Methods Ninety-six patients with essential hypertension received metoprolol （100 mg once daily） as monotherapy for 8 weeks. Twenty-four hours ambulatory blood pressure monitoring and dynamic electrocardiogram were performed before and after treatment. Genotyping analysis was performed using PCR. The association of the ACE gene I/D polymorphism with variations in BP and heart rate （HR） was observed after the 8-week treatment. Results The patients with ACE gene II polymorphism showed greater reduction in 24-hour average HR than those with ID or DD polymorphisms （P=0.045）, no effect of this genotype on the reduction in seating HR or in BP was observed. After adjusting for age, gender, body mass index, BP and HR at baseline, the ACE gene I/D polymorphism was still an independent predictor for variations in 24-hour average HR. Conclusions The II polymorphism in ACE gene could be a candidate predictor for greater reduction in 24-hour average HR in Chinese Han hypertensive patients treated by metoprolol. Greater benefits would be obtained by patients with II polymorphism from the treatment with metoprolol. Larger studies are warranted to validate this finding