ACE基因I/D多态性与风湿性心脏病的相关性研究

目的:探讨血管紧张素转换酶(Angiotensin converting enzyme,ACE)基因插入/缺失(I/D)多态性与中国人风湿性心脏病(Rheumatic heart disease,RHD)易感性的关系.方法:以病例-对照法,采用聚合酶链反应(PCR)检测246例风湿性心脏病患者和223例正常对照组的ACE基因型.病例组进一步分为二尖瓣病变组和联合瓣膜病变组,结合临床资料统计分析各组数据.结果:ACE I/D各基因型在RHD病例组和对照组分布差异无统计学意义,但病例组ACE Ⅰ型等位基因频率高于对照组(70.1％ vs 63.9％),差异有统计学意义(P＜0.05).联合瓣膜病变患者组中,ACE Ⅱ、ID、DD基因型频率分别为51.8％、39.2％和9.0％,I、D等位基因频率分别为71.4％及28.6％.ACE Ⅱ基因型和Ⅰ型等位基因在联合瓣膜病变组和对照组的分布差异均有统计学意义(P＜0.05).结论:ACE基因I/D多态性可能与中国人风湿性心脏病的遗传易感性相关.     

子痫前期血管紧张素转换酶基因多态性与血管紧张素的相关性研究

目的探讨ACE基因I／D多态性与血浆PRA、AngⅡ的相关性。方法应用聚合酶链反应（PCR）和放射免疫法检测子痫前期患者及正常孕妇ACE基因I/D多态性的分布、血浆PRA、AngU水平。结果病理组ACE基因I/D多态性D等位基因分布频率高于对照组（P〈0．05）;血浆AngⅡ水平在病理组和对照组各基因型问无差异（P〉0．05）;病理组携带D等位基因者血浆PRA水平低于对照组愀0．01）;病例组内DD基因型血浆PRA水平低于ID基因型（P〈0．01）;ID基因型血浆PRA水平低于II基因型（P〈0．051;DD基因型血浆PRA水平低于Ⅱ基因型（P〈0．01）。结论（1）ACE基因I／D多态性与子痫前期的发病相关。（2）ACE基因I／D多态性与子痫前期患者血浆AngⅡ水平无关。（3）ACE基因的D等位基因与子痫前期患者血浆PRA水平相关．ACE基因I／D多态性可能通过改变血浆PRA水平参与子痫前期的病理过程。     

血管紧张素转换酶基因多态性与急性脑血管病的关系

急性脑血管病是多基因遗传性疾病.血管紧张素转换酶(ACE)基因是研究的主要侯选基因.在ACE基因的16内含子中存在一种Alu重复序列的插入(I)和缺失(D)的多态性;从而构成2种等位基因I和D,以及3种DNA基因型:DD(缺失纯合子)、ID(缺失插入杂合子)和II(插入纯合子).本文通过对急性脑血管病(脑出血、脑梗塞)患者ACE基因I/D多态性的研究发现,脑梗死组中在50～92岁年龄组DD纯合型频率高于正常对照组(p＜0.05).50岁及其以上的脑出血患者与正常对照组问DD基因型及等位基因频率比较有显著差异(p＜0.01),并显示高血压病和高血压病家族史、脑卒中家族史是脑梗塞主要危险因素,但未发现上述危险因素与ACE基因型有关联(p＜0.05).并且脑梗死患者ACE基因型与HDL、ApoB有关.     

ACE基因多态性与原发性高血压患者血清ACE和血浆AngⅡ水平的相关性

目的研究血管紧张素转化酶(ACE)基因插入/缺失(I/D)多态性与原发性高血压(EH)患者血清ACE、血浆血管紧张素Ⅱ(AngⅡ)水平的相关性。方法选择青岛地区EH患者246例和130例正常对照,测定两组血压、血脂、血糖等临床及生化指标,并对高血压进行分级,同时检测血清ACE、血浆AngⅡ水平,采用聚合酶链反应(PCR),检测ACE基因型,比较不同基因型、不同血压分级患者其血清ACE、血浆AngⅡ水平有无差别。结果EH组中,II、ID、DD基因型患者血清ACE水平分别为(36.69±14.05)U/L,(42.98±16.61)U/L,(49.37±17.43)U/L,组间差异有统计学差异(P<0.05);三组基因型患者血浆AngⅡ水平比较,组间差异无统计学差异(P>0.05);随着高血压分级的升高,血清ACE及血浆AngⅡ水平逐渐增加,差异均有统计学意义(P<0.05);EH患者血清ACE水平与ACE基因多态性之间有相关性(r=0.324,P<0.05)。结论 DD基因型EH患者血清ACE水平明显高于ID型和II型患者,血浆AngⅡ水平在不同基因型间无统计学差异。     

血管紧张素转换酶基因多态性与重度子痫前期及肾功能损害的关系

目的 探讨血管紧张素转换酶(ACE)基因第16内含子插入/缺失(I/D)多态性与重度子痫前期和子病前期肾功能损害的关系.方法 采用聚合酶链反应(PCR)技术检测120例子痫前期(其中轻度67例,重度53例)和60例正常孕妇ACE基因I/D多态性.结果 重度子痫前期组分别与正常孕妇组和轻度子痫前期组比较,ACE基因型分布和等位基因频率均有显著差异(P＜0.01);子痫前期肾功能损害组与无肾功能损害组比较,ACE基因型分布有显著差异(P＜0.05).结论 ACE基因I/D多态性与子痫前期病情相关;ACE基因I/D多态性与子痫前期肾功能损害相关,DD基因型可能是子痫前期肾功能损害的危险因素.     

血管紧张素转化酶基因多态性与血管紧张素转化酶和血管紧张素Ⅱ水平的关系

目的探讨原发性高血压患者血管紧张素转化酶(ACE)基因插入/缺失(I/D)多态性与血清ACE和血管紧张素Ⅱ浓度的关系。方法应用PCR技术测定518例高血压患者的ACE基因型,并测定其ACE、血管紧张素Ⅱ浓度。结果II、ID、DD型患者血浆ACE浓度分别为(33.84±15.99)U/L、(41.1±16.80)U/L、(50.34±18.92)U/L,三种基因型之间的差异有统计学意义(P<0.05);血浆血管紧张素Ⅱ浓度在三种基因型之间的差异无统计学意义(P>0.05)。结论ACE基因多态性与血浆ACE浓度相关,而与血浆血管紧张素Ⅱ浓度无关。     

急性心肌梗死患者血管紧张素Ⅰ转换酶基因多态性及其活性的相关研究

目的探讨血管紧张素Ⅰ转换酶(ACE)插入/缺失(I/D)基因多态性和血清ACE活性与急性心肌梗死(AMI)患者的意义。方法用聚合酶链反应(PCR)法扩增ACE基因第16内含子多态性位点的序列,检测38例AMI患者及32名健康体检者ACE基因,χ2检验比较心肌梗死组、对照组间ACE基因型的频率及等位基因频率。用速率法检测血清ACE活性水平。对C反应蛋白(CRP)、肌酸激酶同工酶(CK-MB)质量、心肌肌钙蛋白(cTNI)含量也进行了检测。结果与对照组比较,AMI患者ACE基因型有明显的分布差异。三种基因型III、D、DD的频率在AMI患者分别为5/38(13%)、14/38(37%)、19/38(50%),在对照组则分别为8/32(25%)、17/32(53%)、7/32(22%)。I、D等位基因频率在AMI组分别为24/76(32%)、52/76(68%);对照组分别为33/64(52%)、31/64(48%)。经χ2检验,差异有统计学意义。ACE基因型与血清ACE浓度相关,DD、ID、II基因型的ACE浓度分别为(61±16)U/L、(49±14)U/L(、38±14)U/L。DD基因型患者的血清cTNI的表达水平明显高于ID型和II型,CRP在各基因型之间差异无统计学意义。结论AMI患者血清ACE活性明显升高。ACE基因型与血清ACE浓度相关,DD型表达最高,II型最低,ID型介于两者之间。DD基因型患者的血清cTNI的表达水平明显高于ID型和II型。     

血管紧张素转化酶基因多态性与妊娠高血压综合征的关系

目的 :探讨血管紧张素转化酶 (ACE)基因插入(I)/缺失 (D)多态性与妊娠高血压综合征 (妊高征 )的关系。方法 :应用聚合酶链反应 (PCR)方法检测41例妊高征患者和50例正常妊娠者的ACE基因型 ,同时检测血浆ACE水平。结果 :妊高征组的DD基因型频率及D等位基因频率分别为39 %和61 % ,均高于对照组的相应频率18 %和38 % ,差别有统计学意义 (P<0.05)。DD基因型的ACE活性显著高于其他2种基因型。结论 :ACE基因缺失多态性可能为妊高征发病的重要遗传因素 ,ACE活性受到基因的调控。     

老年心力衰竭患者心室重构与血管紧张素转换酶基因多态性的相关性及药物干预效果的研究

目的探讨老年充血性心力衰竭(CHF)患者心室重构与血管紧张素转换酶(ACE)基因多态性的相关性,并观察美托洛尔缓释片、依那普利的干预效果。方法选择50例正常对照组和104例老年CHF患者,并将104例老年CHF患者随机分为A组(常规治疗)26例;B组(常规治疗+美托洛尔缓释片)26例;C组(常规治疗+依那普利)26例;D组(常规治疗+美托洛尔缓释片+依那普利)26例,均连续治疗3个月。所有受试着进行ACE基因分型,用放射免疫法测定AngⅡ、ALD;紫外吸收法测定ACE;PCR测定基因多态性;超声心动图测量LVEDD、LVEDV和LVEF。结果老年CHF组DD基因型频率和D等位基因频率较正常对照组明显增高,P<0.01;DD基因型患者血清ACE、AngⅡ、ALD水平明显高于ID型、II型和正常对照组,P<0.01;DD基因型较ID型、II型患者LVEDD、LVEDV明显高,而LVEF明显低,P<0.01;ACEI/D多态性与血清中ACE水平明显相关,DD型水平最高,II型最低;老年CHF伴左心室肥厚组DD基因型频率及D等位基因频率较不伴左室肥厚组明显增高,P<0.01;治疗3个月后,B组及C组中ACEDD基因型患者LVEDD、LVEDV明显低于ID型、II型及A组,而LVEF明显增高;且DD基因型患者的血清ACE、AngⅡ、ALD水平明显低于ID型、II型及A组;联合用药组DD基因型患者的LVEDD、LVEDV明显低于B组及C组,而LVEF明显增高。结论老年CHF患者血清ACE、AngⅡ、ALD水平与ACE基因多态性中DD基因型及D等位基因密切相关;老年CHF患者LVEDD、LVEDV、LVEF与ACE基因多态性中DD型及D等位基因关系密切;ACE基因多态性中DD基因型及D等位基因是老年CHF患者预后的重要预测因素,可作为判定老年CHF患者心室重构、估计病情、判断预后的重要指标之一;美托洛尔缓释片与依那普利均能改善老年CHF的心室重构及预后,但两药联合治疗效果更好,使其病死率进一步降低。     

血管紧张素转换酶基因多态性与血脂代谢异常的相关性研究

目的研究血管紧张素转换酶（ACE）基因多态性与血脂异常之间的相互关系。方法对126例冠心病、高血压病患者和100例健康对照者分别进行ACE基因多态性和血脂[血清胆固醇（CH）、甘油三酯（TG）、高密度脂蛋白（HDL-c）、LDL-c]）、Fib浓度测定,分析ACE基因多态性与血脂及Fib之间的关系。结果疾病组DD基因型频率和D等位基因频率较正常对照组明显增高（P〈0.01）;疾病组CH、TG、LDL-c、Fib水平明显高于对照组（P〈0.05）,而HDL-c水平明显低于对照组（P〈0.05）。且疾病组中ACE基因DD型者与ID、Ⅱ型者间相比差异有统计学意义（P〈0.05）;ACE基因多态性与CH、TG、LDL-c及Fib浓度间呈显著正相关（r值分别为0.671,0.702,0.683,0.653,P值均〈0.01）;与HDL-c浓度间存在显著负相关（r=-0.648,P〈0.001）。结论 ACE基因DD型和D等位基因与血脂代谢异常及血浆Fib有关,而与Ⅰ等位基因无关。     

ACE inhibitors

Edited by P. D'Orlèans-Juste & G. E. Plante Published by Birkhauser [Milestones in drug therapy series] 187 pages, price @116, ISBN 3-7643-5982-X     

ACE inhibitor-mediated angioedema

Angioedema (AE) occurring during ACE inhibitor therapy (ACEi-AE) is a rare complication involving between 0.1 and 0.7% of treated patients. AE can also complicate other therapeutic regimens that block the renin-angiotensin aldosterone system. Other drugs, such as immune suppressors, some type of antidiabetics or calcium antagonists, can increase the likelihood of ACEi-AE when associated to ACEi. There is a clear ethnic predisposition, since African-Americans or Hispanics show a higher prevalence of this condition compared to Caucasians. At least in African-Americans the genetic predisposition accounts for a general higher prevalence of AE, independently from the cause. People that experience ACEi-AE may have some recurrence when they are switched to an angiotensin-receptor blocker (ARB); however, epidemiological studies on large cohorts have shown that angiotensin receptor blockers (ARB) do not increase the likelihood of AE compared to other antihypertensives. Clinical manifestations consist of edema of face, lips, tongue, uvula and upper airways, requiring intubation or tracheotomy in severe cases. Attacks last for 48–72 h and require hospital admission in most cases. Intestinal involvement with sub-occlusive symptoms has also been reported.The pathogenesis of ACEi-AE depends mainly on a reduced catabolism and accumulation of bradykinin, which is normally metabolized by ACE. Genetic studies have shown that some single nucleotide polymorphisms at genes encoding relevant molecules for bradykinin metabolism and action may be involved in ACEi-AE, giving a basis for the ethnic predisposition. Treatment of ACEi-AE is still a matter of debate. Corticosteroids and antihistamines do not show efficacy. Some therapeutic attempts have shown some efficacy for fresh frozen plasma or C1 inhibitor concentrate infusion. Interventional studies with the specific bradykinin receptor antagonist icatibant have shown conflicting results; there might be a different ethnic predisposition to icatibant efficacy which has been proven in caucasian but not in black patients.     

ACE inhibitors and proteinuria

This review discusses the clinical consequences of uninary protein loss and the effects of inhibitors of the angiotensin converting enzyme (ACE) on this clinical finding. Proteinuria appears to be an important risk factor for renal function deterioration and for cardiovascular mortality. ACE inhibitors have been shown to reduce proteinuria more effectively than other antihypertensives. Their antiproteinuric effect seems to be independent of the underlying renal disease, and is mediated by a specific, not yet fully elucidated mechanism. Urinary protein loss related phenomena, such as hypoalbuminemia and aberrant lipoprotein profile, tend to improve also during ACE inhibitor treatment. Furthermore, ACE inhibition has been shown to prevent the renal function deterioration that is frequently observed in patients with renal disease. Interestingly, it has recently been shown that in proteinuric patients with renal disease the initial proteinuria lowering response to ACE inhibition predicts long-term renal function outcome during this treatment: the more proteinuria is lowered during the first months, the better renal function will be preserved over the following years. Because of these favorable effects ACE inhibitors have become a widely used class of agents in nephrology. They are not only prescribed for lowering blood pressure in the hypertensive renal patient, but also as symptomatic treatment of patients with proteinuria, and to prevent renal function loss in patients with both diabetic and non-diabetic renal disease.R.T. Gansevoort, D. de Zeeuw, P.E. de Jong, Ace inhibitors and proteinuria. Pharm World Sci 1996; 18(6): 204–210.     

ACE Inhibition in Hypertension

Ongoing developments in our understanding of cardiovascular disease, together with the introduction of new drugs to treat these conditions, has led to much debate over the optimal management of hypertension. The ALLHAT study showed no major differences in cardiovascular outcome among three major classes of antihypertensive drugs. Indeed, large meta-analyses have substantiated this view, and most experts would agree that BP reduction matters more than the choice of antihypertensive agent. However, recently published data from the ASCOT-BPLA trial for hypertensive patients at moderate risk of cardiac events have caused some experts to re-evaluate this view. The recent Blood Pressure Lowering Treatment Trialists' Collaboration publication confirmed this change. In the ASCOT-BPLA trial, antihypertensive therapy based on amlodipine+perindopril significantly reduced total and cardiovascular mortality as well as other clinically relevant outcomes in comparison with a traditional strategy based on atenolol and a thiazide diuretic, despite both regimens producing nonsignificantly different reductions in brachial BP. These findings suggest that amlodipine/perindopril may exert a beneficial effect by acting on other parameters such as central BP or BP variability. ACE inhibitors have been shown to have antiatherosclerotic and antithrombogenic effects, to improve endothelial dysfunction, and to prevent cardiac remodeling in patients with coronary heart disease. In this regard, perindopril, which has relatively high affinity for ACE and true 24-hour duration of action, is one of the most extensively studied ACE inhibitors. More recent data suggest that ACE inhibitors reduce arterial stiffness, an independent risk factor for cardiovascular events, and have a beneficial effect on central aortic BP, thus providing a possible explanation for the findings of ASCOT-BPLA and confirming that ACE inhibitors are an appropriate first choice for patients with hypertension.     

Angiotensin-converting enzyme (ACE) dimerization is the initial step in the ACE inhibitor-induced ACE signaling cascade in endothelial cells

The binding of angiotensin-converting enzyme (ACE) inhibitors to ACE initiates a signaling cascade that involves the phosphorylation of the enzyme on Ser1270 as well as activation of the c-Jun NH2-terminal kinase (JNK) and leads to alterations in gene expression. To clarify how ACE inhibitors activate this pathway, we determined their effect on the ability of the enzyme to dimerize and the role of ACE dimerization in the initiation of the ACE signaling cascade. In endothelial cells, ACE was detected as a monomer as well as a dimer in native gel electrophoresis and dimerization/oligomerization was confirmed using the split-ubiquitin assay in yeast. ACE inhibitors elicited a rapid, concentration-dependent increase in the dimer/monomer ratio that correlated with that of the ACE inhibitorinduced phosphorylation of ACE. Cell treatment with galactose and glucose to prevent the putative lectin-mediated self-association of ACE or with specific antibodies shielding the N terminus of ACE failed to affect either the basal or the ACE inhibitor-induced dimerization of the enzyme. In ACE-expressing Chinese hamster ovary cells, ACE inhibitors elicited ACE dimerization and phosphorylation as well as the activation of JNK with similar kinetics to those observed in endothelial cells. However, these effects were prevented by the mutation of the essential Zn2+-complexing histidines in the C-terminal active site of the enzyme. Mutation of the N-terminal active site of ACE was without effect. Together, our data suggest that ACE inhibitors can initiate the ACE signaling pathway by inducing ACE dimerization, most probably via the C-terminal active site of the enzyme.     

ACE Inhibition with Moexipril

ACE inhibitors induce metabolic changes and exert cardioprotective and vasoprotective properties, some of which cannot be attributed to their antihypertensive effect per se. Moexipril is an ACE inhibitor with a lipophilicity in the same range as quinapril, benazepril or ramipril, and so can readily penetrate lipid membranes and thus target tissue ACE in addition to plasma ACE. Evidence from animal studies shows similar and significant (p ? 0.05) reductions in tissue ACE activity for moexipril and quinapril. Moexipril may improve endothelial dysfunction; moexiprilat and ramiprilat have demonstrated greater activity than Captopril, enalaprilat and quinaprilat in isolated endothelium-denuded segments of the rabbit jugular vein where bradykinin elicits a constrictor response, mediated by activation of the bradykinin B₂ receptor. ACE inhibitors, including moexipril, may exert neuroprotective effects. Moexipril promoted neuronal survival in vitro and it is thought that this neuroprotective effect is due to free radical scavenging properties of the drug. ACE inhibitors can also decrease progression of renal insufficiency in patients with various underlying renal diseases. Moexipril may also have a renoprotective effect as it increased the ultrafiltration coefficient and normalized urinary protein excretion in rat models. Preclinical studies indicate that the renin-angiotensin-aldosterone system may play a role in the regulation of bone resorption and moexipril had no adverse effects on bone metabolism in animal models and the drug did not hamper the osteoprotective effects of estrogen. Reduction in left ventricular mass with moexipril in patients with hypertension was similar in magnitude to the effect of other ACE inhibitors. When investigated in hypertensive patients with an elevated cardiovascular risk, moexipril increased arterial distensibility and demonstrated antioxidative properties in addition to efficiently controlling blood pressure. Moexipril does not adversely affect serum levels of uric acid, lipids, blood glucose levels and plasma insulin levels and can be co-administered with hormone replacement therapy. Moreover, quality-of-life data suggest favorable effects of moexipril treatment in a patient population at high cardiovascular risk.