Association of the angiotensinogen M235T and angiotensin-converting enzyme insertion/deletion gene polymorphisms in Turkish type 2 diabetic patients with and without nephropathy

OBJECTIVE: Recent studies have suggested an association between a deletion variant of the angiotensin-converting enzyme (ACE) gene and diabetic nephropathy. However, this finding has not been confirmed by all investigators. Furthermore, an M235T variant of the angiotensinogen (AGT) gene has been associated with hypertension, an important risk factor for the development and progression of diabetic nephropathy. RESEARCH DESIGN AND METHODS: We investigated the relationship of the ACE insertion/deletion (I/D) and AGT M235T gene polymorphisms in Turkish patients with type 2 diabetes mellitus (DM) with and without diabetic nephropathy. A total of 102 individuals were screened for the presence of the ACE I/D and AGT M235T polymorphism: 46 individuals who had type 2 DM with diabetic nephropathy and, as controls, 56 individuals who had type 2 DM without diabetic nephropathy. Gene polymorphisms were determined by the specific melting temperature (T(m)) values of the resulting amplicons after real-time online polymerase chain reaction and melting curve analysis. RESULTS: The frequencies of the ACE DD, ID, and II genotypes were 34.8%, 37.0%, and 28.3%, respectively, among type 2 diabetic patients with nephropathy, and 33.9%, 42.9%, 23.2%, respectively (P=.788), in the control subjects without diabetic nephropathy. On the other hand, the frequencies of the AGT MM, MT, and TT genotypes among the same groups were 26.1%, 52.2%, 21.7% and 26.8%, 57.1%, 16.1%, respectively (P=.758). CONCLUSIONS: There were no differences in the frequencies of the AGT M235T and ACE I/D genotypes between Turkish patients with type 2 DM with and without nephropathy.     

血管紧张素原基因多态性与肥厚型心肌病的相关性分析

目的 探讨血管紧张素原(AGT)基因的单核苷酸多态性(SNP)位点A943580G与肥厚型心肌病(HCM)的相关性.方法 用PCR-RFLP方法对225个HCM病人和243个正常人的AGT的SNP位点A943580G进行基因分型(此位点与黑色人种中的高血压病人的最大早期充盈速度有关).结果 携带AA和AG基因型的HCM病人的左心室流出道梗阻率明显高于GG基因型的梗阻率(30.1%比17.0%,P＜0.05).通过对发病年龄,性别,室间隔厚度,HCM家族史以及家族猝死史进行调整后,携带A等位基因(AA AG)的HCM病人左心室流出道梗阻率要高于GG基因型病人(OR=2.4,95%CI 1.2 to 4.8).结论 AGT的A等位基因可能是HCM病人发生左心室流出道梗阻的危险因子.     

肾素-血管紧张素-醛固酮系统基因多态性与大动脉粥样硬化性卒中的相关性:中国南方汉族人群研究

目的 研究肾素-血管紧张素-醛固酮系统血管紧张素原(angiotensinogen,AGT)基因M235T、血管紧张素Ⅱ1型受体(angiot ensinⅡtype 1 receptor,AGTR1)基因A1166C、醛固酮合酶( aldosterone synthase,CYP11B2)基因- 344C/T多态性与中国南方汉族人群大动脉粥样硬化性卒中(large-artery atherosclerosis,LAA)的相关性.方法 采用聚合酶链反应和基因测序技术对中国南方汉族LAA患者和正常对照者AGT基因M235T、ATGR1基因A1166C和CYP11B2基因- 344C/T多态性进行基因分型,并通过二分类logistic回归分析确定这3种基因多态性与LAA的相关性.结果 共纳入LAA患者107例和142名健康对照者.LAA组AGT基因235TT基因型(66.36％对50.70％,x2=6.122,P=0.047)和T等位基因(79.44％对70.07％,x2=5.581,P=0.018)频率显著高于对照组,AGTR1基因1166CC基因型(0％对0％,x2=1.494,P=0.222)和C等位基因(7.48％对4.93％,x2=1.399,P=0.237)频率与对照组无显著性差异,CYP11B2基因- 344CC基因型(9.35％对4.23％,x2=3.603,P=0.165)和C等位基因(27.10％对26.06％,x2=0.069,P=0.793)频率与对照组亦无显著性差异.二分类logistic回归分析显示,这3种基因多态性与单纯性LAA患病均无显著相关性.合并高血压的LAA患者AGT基因235TT基因型(68.00％对41.90％,x2=12.446,P=0.002)和T等位基因(79.33％对64.76％,x2=8.993,P=0.003)频率均显著高于血压正常对照组,logistic回归分析显示,暴露于TT基因型的优势比(odds ratio,OR)为2.153[ 95％可信区间(confidence interval,CI)0.789 ～5.872],T等位基因的OR值为2.089(95％ CI1.285 ～3.396).结论 AGT基因M235T多态性与南方汉族人群单纯性LAA无关,但可能与合并高血压的LAA患病风险相关;CYP11B2基因- 344C/T多态性和AGTR1基因A1166C多态性与南方汉族人群LAA发病无关.     

Role of tagged SNPs of the AGT gene in causing susceptibility to essential hypertension

Aim: Angiotensinogen (AGT) is one of the candidate genes that has been extensively investigated for association of its variants with essential hypertension. Studies focusing on the contribution of tagged single nucleotide polymorphisms (SNPs) in the AGT gene are limited and lacking from Indian population. Hence, the present study was carried out to examine the role of five tagged SNPs viz., g.6147G>A (rs7539020), g.5978A>G (rs2493134); g.6241T>C (rs1078499), g.7781G>T (rs11122577), and g.5855G>A (rs3789678) in the development of hypertension. Materials and Methods: 202 hypertensives and 222 normotensives were screened for five tagged SNPs using the method of polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Results: The present study revealed significant association of g.5855G>A polymorphism with essential hypertension in different logistic regression models wherein protection was conferred by g.5855G>A against developing the condition. The polymorphism led to the creation of new exonic splicing enhancer and destruction of exonic splicing silencer site thereby enhancing the process of mRNA splicing. The haplotypes AGTG and GACG were found to have a significant protective effect. Other polymorphisms did not show any significant association with hypertension. Conclusion: The present study is the first one to report the protective role of g.5855G>A polymorphism in the development of essential hypertension. The results reflect possibility of ethnic variation in the contribution of g.5855G>A polymorphism of the AGT gene to essential hypertension.     

血管紧张素原基因T174M和血管紧张素转换酶基因I/D多态性与急性心肌梗死的相关性

目的探讨中国汉族人群血管紧张素转换酶和血管紧张素原基因型的分布及其与急性心肌梗死的关系。方法应用聚合酶链反应技术,对112例急性心肌梗死患者、128例非冠心病患者血管紧张素转换酶I/D多态性及血管紧张素原T174M多态性进行检测。结果血管紧张素转换酶基因型分布及等位基因频率在病例组及对照组间差异有显著性(P<0.01)。病例组和对照组血管紧张素原基因型及等位基因频率总体分布差异亦有显著性(P<0.05)。联合基因分析显示,急性心肌梗死组血管紧张素转换酶DD基因型 血管紧张素原174MM基因型频率显著高于对照组(P<0.01),具有该联合基因型者发生冠心病的风险比数比(OR=8.467)明显高于单独具有血管紧张素转换酶DD基因型(OR=2.558)或血管紧张素原174MM基因型(OR=6.176)者。结论血管紧张素原T174M基因多态性中M等位基因和血管紧张素转换酶I/D基因多态性基因中的D等位基因是中国汉族人群冠心病发病的危险因素之一。同时具有血管紧张素转换酶DD型及血管紧张素原174MM型发生冠心病的相对风险显著高于单基因血管紧张素转换酶DD型及单基因血管紧张素原174MM型。     

Genetic polymorphisms in vasoactive genes and preeclampsia: a meta-analysis

There are controversies in reports on the association of polymorphisms in endothelial nitric oxide synthase, angiotensinogen, angiotensin receptor type 1 and angiotensin-converting enzyme genes with an increased risk of developing preeclampsia. We performed a systematic search of published case-control studies through the PubMed database up to January 2006, and report the results of a meta-analysis of polymorphisms investigated in more than five studies: Glu298Asp in eNOS gene (9 analyses involving 1055 patients and 1788 controls), Met235Thr in AGT gene (13 analyses involving 1128 patients and 2278 controls), and intron 16 insertion-deletion polymorphism in ACE gene (10 analyses involving 1121 patients and 1361 controls). Statistically significant associations with preeclampsia were identified for the Met235Thr/AGT polymorphism: OR 1.65 (95% CI 1.19, 2.29) if the polymorphism is considered under the dominant genetic model, and OR 1.54 (95% CI 1.12, 2.11) under the recessive model. For insertion-deletion/ACE polymorphism, statistical significance was demonstrated when the polymorphism was considered under the recessive model: OR 1.51 (95% CI 1.17, 1.94). No single polymorphism was identified as having a major effect.     

血管紧张素原基因T174M变异与肝硬化的相关性

目的:研究血管紧张素原(angiotensinogen,AGT)基因T174M分子变异与肝硬化的关系.方法:提取正常人64例和肝硬化患者65例白细胞基因组DNA,通过PCR、限制性片段长度多态性和测序等技术,观察AGT基因型在肝硬化组和正常组分布的差异.结果:AGT基因T174M位点MT和TT基因型的频率在正常组和肝硬化组分别为82.8%、17.2%和84.6%、15.4%,两组之间不存在差异(χ~2=0.077,P>0.05).结论:血管紧张素原基因T174M变异与肝硬化没有显著关系.     

抑制NF-κB活性下调高糖培养的大鼠肾小球系膜细胞血管紧张素原表达水平

在体外原代培养的SD大鼠肾小球系膜细胞中,观察高糖培养条件下血管紧张素原(AGT)表达和血管紧张素Ⅱ(AngⅡ)水平变化,以及吡咯烷二硫代氨基甲酸酯(PDTC)的干预作用.结果 显示高糖上调ACT mRNA(0.29±0.07对0.20±0.05,P<0.05)和蛋白(0.66±0.23对0.37±0.15,P<0.05)表达以及AngⅡ分泌[(9.85+2.08对7.50±1.51)ps/ml,P<0.05]水平,PDTC通过抑制NF-κB活性下调其水平.     

高血压家系AGT基因与细胞因子关系的研究

目的　研究原发性高血压家系血管紧张素原 (AGT)基因多态性及与细胞因子 (IL 1、IL 6、TNF)的关系。方法　对高血压组 40例和家系对照组 38例用PCR RFLP方法分析血AGT基因型 ,用ELISA方法测定血IL 1、IL 6和TNF浓度。结果　发现AGT2 35TT型在高血压组占 70 % ,在家系对照组占 42 %。血IL 1和TNF浓度在高血压组比家系对照组显著升高 ,在AGT基因2 3 5TT型中比2 35TM型中显著升高。结论　AGT基因M2 35T变异是高血压发病的重要危险因素之一 ,细胞因子IL 1和TNF与高血压发病和AGT基因2 35TT型相关 ,它们在高血压发病中可能起重要的AGT基因调控作用     

载脂蛋白B、载脂蛋白E及血管紧张素原基因多态性与冠心病的关系

目的探讨载脂蛋白B、E（ApoB、ApoE）基因及血管紧张素原基因（AGT）多态性与冠心病（CHD）的相关性。方法采用基因芯片技术分析89例CHD患者和78例非CHD患者的ApoBXbaI、ApoEl12／158及AGTM235T基因多态性及等位基因频率。结果CHD组ApoBXbaI、ApoEl12／158及AGTM235T基因型分布与对照组相比差异有统计学意义（P〈0．05）。CHD组的Apo BXba I的X^＋ X^＋基因型及等位基因X’频率显著高于对照组,差异有统计学意义（P〈0．05）,ApoE112／158的ε^4/、ε^4/4基因型及等位基因￡。频率高于对照组,差异有统计学意义（P〈O．05）;CHD组AGT—TT基因型频率及T等位基因频率均明显高于对照组,差异有统计学意义（P〈0．05）。结论ApoBXbaI、ApoEll2／158和AGTM235T的基因多态性可能是中国人CHD的危险因素。ApoB Xba I等位基因X^＋;ApoE112／158的等位基因ε^4和AGT M235T基因的T等位基因是CHD的重要遗传标记。