Association of angiotensin-converting enzyme I/D polymorphism with heart failure: a meta-analysis

Acute Responses of Cardiac Biomarkers to Intermittent and Continuous Exercise Are Related to Age Difference but Not I/D Polymorphism in the ACE Gene

Purpose

The purpose of this study was to determine the (i) cardiac biomarker (cTnI and NT-proBNP) responses to moderate-intensity continuous exercise (MICE) and high-intensity interval exercise (HIIE) in the middle-aged and young groups, (ii) relationship of post-exercise cardiac biomarker release between these two age groups, and (iii) investigate whether insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene is associated with predisposition to cardiac damage after exercise in Iranian men.

Methods

We examined cTnI and NT-proBNP in 29 middle-aged (54.5 ± 4.6 years) and 28 young (22.7 ± 4.2 years) soccer players before and after HIIE and MICE running tests.

Results

The middle-aged soccer players had higher baseline cTnI (0.015 ± 0.007 ng/ml vs. 0.010 ± 0.006 ng/ml; P = 0.01) and NT-proBNP (30.7 ± 13.6 ng/L vs. 18.4 ± 8.3 ng/L; P < 0.001) values compared with the young group. The changes with exercise (ΔcTnI: 13 vs. 11 ng/ml and ΔNT-proBNP: 18 vs. 11 ng/L) were also higher in the middle-aged group. No subject exceeded the upper reference limit for cTnI and NT-proBNP. Considering three ACE genotypes, the mean cTnI and NT-proBNP values of middle-aged and young groups did not show any significant difference.

Conclusion

Marked differences in baseline and post-exercise cTnI and NT-proBNP values were observed, which were related to age differences but not to ACE genotypes.

Study of angiotensin-converting enzyme insertion/deletion polymorphism, enzyme activity and oxidized low density lipoprotein in Western Iranians with atherosclerosis: a case-control study

Background

It has been indicated that Angiotensin-Converting Enzyme Insertion/Deletion (ACE I/D) polymorphism (rs4646994) could be regarded as a genetic factor that raises the risk of CAD through its impact on the activity of Angiotensin-Converting Enzyme (ACE) and angiotensin II level. The present study seeks to examine the relationship between ACE I/D polymorphism with the risk of atherosclerosis. Moreover, its potential effects on ACE activity and oxLDL level are investigated.

Methods

In this study, 145 healthy individuals and 154 patients (143 males and 156 females) were selected among the subjects referred to Shahid Madani Hospital. Atherosclerosis was determined in all subjects with gold standard angiography. Blood samples were collected, used to isolate white blood cells (WBC) and serum separation. The DNA was extracted and the polymorphism was determined by polymerase chain reaction (PCR). The enzyme activity was measured using high-performance liquid chromatography (HPLC).

Results

This study indicated that patients with atherosclerosis had higher levels of oxidized Low-Density Lipoprotein (oxLDL) and ACE activity (P < 0.05) as compared to controls. Although we found a significant association between ACE I/D polymorphism genotype and the allele with atherosclerosis in the male group, there were no association when the entire patient group was compared to the entire control group.

Conclusion

Our study revealed the ACE I/D polymorphism of the ACE gene may not be an independent risk factor in the development of atherosclerosis and evaluation of ACE activity level is more important in evaluating the risk of disease. The researchers found no relation between ACE I/D polymorphism and atherosclerosis and also between types of genotype, ACE activity, and OxLDL level.

The use of ACE INDEL polymorphism as a biomarker of coronary artery disease (CAD) in humans with Mediterranean-style diet

The ACE INDEL gene polymorphisms are strongly associated with CAD. Therefore, the present study was undertaken to investigate the relationship between ACE INDEL polymorphism and CAD in Turkish Cypriots whose are expected to have Mediterranean-style diet. 273 Turkish Cypriot descent volunteer subjects (186 controls and 87 CAD patients) participated in this study. Genotyping for the ACE INDEL polymorphism was performed by PCR-RFLP analysis. Biochemical parameters except the glucose and triglyceride lipid level were all within normal limits. Glucose level was found significant (p = 0.019) and triglyceride level was observed at the borderline for significance (p = 0.050) in participants according to WHO guidelines. With the respect to the genotype and allele distributions of ACE INDEL, the results showed statistically significant in CAD patients (p = 0.034) and not significant (p = 0.190) in controls. Haplotype analysis showed that D allele was more frequent in patients compared to controls. Thus, there is a statistically significant association with CAD disease with DD genotypes (p = 0.030) in Turkish Cypriot population. The results indicated that ACE INDEL polymorphism is an important predictor of coronary artery disease in Turkish Cypriots. Although 47% of the studied Turkish Cypriot population carry the D allele (p = 0.07), protocols should be developed for prevention strategies immediately.

At the heart of programming: the role of micro-RNAs

Epidemiological and experimental observations tend to prove that environment, lifestyle or nutritional challenges influence heart functions together with genetic factors. Furthermore, when occurring during sensitive windows of heart development, these environmental challenges can induce an 'altered programming' of heart development and shape the future heart disease risk. In the etiology of heart diseases driven by environmental challenges, epigenetics has been highlighted as an underlying mechanism, constituting a bridge between environment and heart health. In particular, micro-RNAs which are involved in each step of heart development and functions seem to play a crucial role in the unfavorable programming of heart diseases. This review describes the latest advances in micro-RNA research in heart diseases driven by early exposure to challenges and discusses the use of micro-RNAs as potential targets in the reversal of the pathophysiology.

Genetics and genomics of dilated cardiomyopathy and systolic heart failure

Heart failure is a major health burden, affecting 40 million people globally. One of the main causes of systolic heart failure is dilated cardiomyopathy (DCM), the leading global indication for heart transplantation. Our understanding of the genetic basis of both DCM and systolic heart failure has improved in recent years with the application of next-generation sequencing and genome-wide association studies (GWAS). This has enabled rapid sequencing at scale, leading to the discovery of many novel rare variants in DCM and of common variants in both systolic heart failure and DCM. Identifying rare and common genetic variants contributing to systolic heart failure has been challenging given its diverse and multiple etiologies. DCM, however, although rarer, is a reasonably specific and well-defined condition, leading to the identification of many rare genetic variants. Truncating variants in titin represent the single largest genetic cause of DCM. Here, we review the progress and challenges in the detection of rare and common variants in DCM and systolic heart failure, and the particular challenges in accurate and informed variant interpretation, and in understanding the effects of these variants. We also discuss how our increasing genetic knowledge is changing clinical management. Harnessing genetic data and translating it to improve risk stratification and the development of novel therapeutics represents a major challenge and unmet critical need for patients with heart failure and their families.

Determined to Fail--the Role of Genetic Mechanisms in Heart Failure

Genetic variants contribute to several steps during heart failure pathophysiology. The mechanisms include frequent polymorphisms that increase the susceptibility to heart failure in the general population and rare variants as causes of an underlying cardiomyopathy. In this review, we highlight recent discoveries made by genetic approaches and provide an outlook onto the role of epigenetic modifiers of heart failure.

Genetic polymorphisms associated with heart failure: A literature review

Objective

To review possible associations reported between genetic variants and the risk, therapeutic response and prognosis of heart failure.

Methods

Electronic databases (PubMed, Web of Science and CNKI) were systematically searched for relevant papers, published between January 1995 and February 2015.

Results

Eighty-two articles covering 29 genes and 39 polymorphisms were identified.

Conclusion

Genetic association studies of heart failure have been highly controversial. There may be interaction or synergism of several genetic variants that together result in the ultimate pathological phenotype for heart failure.

Genetics and heart failure: a concise guide for the clinician

The pathogenesis of heart failure involves a complex interaction between genetic and environmental factors. Genetic factors may influence the susceptibility to the underlying etiology of heart failure, the rapidity of disease progression, or the response to pharmacologic therapy. The genetic contribution to heart failure is relatively minor in most multifactorial cases, but more direct and profound in the case of familial dilated cardiomyopathy. Early studies of genetic risk for heart failure focused on polymorphisms in genes integral to the adrenergic and renin-angiotensin-aldosterone system. Some of these variants were found to increase the risk of developing heart failure, and others appeared to affect the therapeutic response to neurohormonal antagonists. Regardless, each variant individually confers a relatively modest increase in risk and likely requires complex interaction with other variants and the environment for heart failure to develop. Dilated cardiomyopathy frequently leads to heart failure, and a genetic etiology increasingly has been recognized in cases previously considered to be "idiopathic". Up to 50% of dilated cardiomyopathy cases without other cause likely are due to a heritable genetic mutation. Such mutations typically are found in genes encoding sarcomeric proteins and are inherited in an autosomal dominant fashion. In recent years, rapid advances in sequencing technology have improved our ability to diagnose familial dilated cardiomyopathy and those diagnostic tests are available widely. Optimal care for the expanding population of patients with heritable heart failure involves counselors and physicians with specialized training in genetics, but numerous online genetics resources are available to practicing clinicians.

Association of insertion/deletion polymorphism of angiotensin-converting enzyme gene among Malay male hypertensive subjects in response to ACE inhibitors

INTRODUCTION

Several studies show that the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene has been associated with hypertension in various populations. The present study sought to determine the association of the I/D gene polymorphism among Malay male essential hypertensive subjects in response to ACE inhibitors (enalapril and lisinopril).

MATERIALS AND METHODS

A total of 72 patients with newly diagnosed hypertension and 72 healthy subjects were recruited in this study. Blood pressure was recorded from 0 to 24 weeks of treatment with enalapril or lisinopril. Genotyping of the I/D polymorphism was carried out using a standard PCR method.

RESULTS

Statistically significant association of the D allele of the ACE gene was observed between the case and control subjects (p < 0.01). There was a decrease in blood pressure in the patients carrying the DD genotype (SBP=18.5±8.1 mmHg, DBP=15.29±7.1 mmHg) rather than the ID (SBP=4.1±3.3 mmHg, DBP=9.1±3.5 mmHg) and II genotypes (SBP= 3.0±0.2 mmHg, DBP 0.11±6.1 mmHg) of the ACE gene.

CONCLUSION

Patients carrying the DD genotype had higher blood pressure-lowering response when treated with ACE inhibitors enalapril or lisinopril than those carrying ID and II genotypes, suggesting that the D allele may be a possible genetic marker for essential hypertension among Malay male subjects.

Heart failure in China: a review of the literature

Heart failure (HF) is a serious disease associated with high morbidity and mortality. In China, as in other countries, it is a common cause for hospital admission; however, as yet there are few data documenting the epidemiology and management of HF in China, or quality of life-related considerations in this population. This review aims to identify relevant Chinese and English language publications that discuss the causes, risks, treatment, and health outcomes (costs, health-related quality of life) of HF in China (excluding Taiwan and Hong Kong). The prevalence of HF in China appears to be lower than that reported in many Western countries, including the US. Hypertension and coronary heart disease are the leading causes of HF in China, as they are in many Western nations, potentially highlighting the improvement in socioeconomic conditions in China. Evidence suggests that use of newer pharmacological agents for the treatment of HF is increasing; however, it is still believed that there is a lack of physician knowledge regarding newer, more effective treatment options, with rural (poor) areas appearing to be the most reliant on older, less expensive, medications. Interest in Chinese quality of life measures for HF has risen recently, with the development of valid and reliable rating scales in the Chinese population. Although the amount of available literature on HF in China is improving, there remain significant gaps in our understanding of the issue, and further research is needed to provide a reliable Chinese evidence base for the improvement of clinical practice.

Gene polymorphisms and thyroid function in patients with heart failure

We evaluated nuclear factor kappa B {NFkB, rs28362491 [-94ins/delATTG (W/D)]} and angiotensin converting enzyme {ACE; rs1799752 [Ins(I)/Del(D)]} gene polymorphisms and their correlation with thyroid function in patients with heart failure (HF). Peak oxygen uptake (VO(2)) was evaluated (by Weber classification) during a symptom-limited cardiopulmonary exercise test in 194 patients. Thyroid-stimulating hormone, triiodothyronine (T3), thyroxine (T4), and free (F) T3 and FT4 were also measured. According to their cardiovascular (CV) capacity, patients were subdivided into four groups: group A included patients with peak VO(2) >20 ml/kg/min, group B 16-20 ml/kg/min, group C 10-16 ml/kg/min, and group D 6-10 ml/kg/min. Patients were also genotyped for NFkB and ACE genetic variants. T3 was increased and FT3 was decreased for every raise in Weber's classification (p = 0.007 and p = 0.012, respectively). Del carriers had elevated FT3 levels compared with Ins carriers (p = 0.021). Patients with II genotype had elevated T4 levels compared with ID genotype (p = 0.044). Both T4 and FT4 were decreased in D allele carriers (p = 0.007 and p = 0.045, respectively). Thyroid hormones correlated with CV capacity. Associations between the NFkB and ACE gene polymorphisms and thyroid hormones levels were also observed. Further larger studies are required to clarify genes contribution in HF.

Angiotensin-converting enzyme genetic polymorphism: its impact on cardiac remodeling

BACKGROUND

The role of angiotensin-converting enzyme genetic polymorphisms as a predictor of echocardiographic outcomes on heart failure is yet to be established. The local profile should be identified so that the impact of those genotypes on the Brazilian population could be identified. This is the first study on exclusively non-ischemic heart failure over a follow-up longer than 5 years.

OBJECTIVE

To determine the distribution of angiotensin-converting enzyme genetic polymorphism variants and their relation with echocardiographic outcome of patients with non-ischemic heart failure.

METHODS

Secondary analysis of the medical records of 111 patients and identification of the angiotensin-converting enzyme genetic polymorphism variants, classified as DD (Deletion/Deletion), DI (Deletion/Insertion) or II (Insertion/Insertion).

RESULTS

The cohort means were as follows: follow-up, 64.9 months; age, 59.5 years; male sex, 60.4%; white skin color, 51.4%; use of beta-blockers, 98.2%; and use of angiotensin-converting-enzyme inhibitors or angiotensin receptor blocker, 89.2%. The angiotensin-converting enzyme genetic polymorphism distribution was as follows: DD, 51.4%; DI, 44.1%; and II, 4.5%. No difference regarding the clinical characteristics or treatment was observed between the groups. The final left ventricular systolic diameter was the only isolated echocardiographic variable that significantly differed between the angiotensin-converting enzyme genetic polymorphisms: 59.2 ± 1.8 for DD versus 52.3 ± 1.9 for DI versus 59.2 ± 5.2 for II (p = 0.029). Considering the evolutionary behavior, all echocardiographic variables (difference between the left ventricular ejection fraction at the last and first consultation; difference between the left ventricular systolic diameter at the last and first consultation; and difference between the left ventricular diastolic diameter at the last and first consultation) differed between the genotypes (p = 0.024; p = 0.002; and p = 0.021, respectively).

CONCLUSION

The distribution of the angiotensin-converting enzyme genetic polymorphisms differed from that of other studies with a very small number of II. The DD genotype was independently associated with worse echocardiographic outcome, while the DI genotype, with the best echocardiographic profile (increased left ventricular ejection fraction and decreased left ventricular diameters).

Pharmacogenomics and heart failure in congenital heart disease

Congenital heart disease (CHD) constitutes a lifelong challenge in heart failure management. Current therapy is based mainly on physiologic principles extrapolated from the management of left ventricular failure in adult populations with either ischemic or nonischemic cardiomyopathy. However, there is good evidence of genomic variability in the origin and progression of CHD that suggests the need for a individualized approach to treatment. The developing science of pharmacogenomics presents an opportunity for CHD management broadly, and especially in the context of heart failure. There is growing evidence that individualizing drug therapy for these patients might be beneficial, and that prediction of response to therapy might be possible by incorporating genomic data into the treatment algorithm for individual patients.

Genetic prediction of heart failure incidence, prognosis and beta-blocker response

Heart failure (HF) is a widespread syndrome due to left ventricular dysfunction with high mortality, morbidity and health-care costs. Beta-blockers, together with diuretics and ACE-inhibitors or angiotensin receptor blockers, are a cornerstone of HF therapy, as they reduce mortality and morbidity. Nevertheless, their efficacy varies among patients, and genetics is likely to be one of the modifying factors. In this article, literature on the role of candidate genes on the development of HF, its prognosis and pharmacogenomics of β-blockers in patients with HF is reviewed. The available findings do not support, at the present time, a role for genetic tests in the treatment of HF. More large-scale genome-wide studies with adequate methodology and statistical analysis are required before considering genetic tailoring of HF therapy in patients with systolic HF.

Genetics of heart failure

Heart failure (HF) occurs when the cardiac output, no longer compensated by endogenous mechanisms, fails to meet the metabolic demands of the body. In most populations, the prevalence of heart failure continues to rise, constituting a major public health burden, especially in developed countries. There is some evidence that the risk of HF in the general population depends on genetic predisposition, necessarily characterised by a very complex architecture. In a small, but probably underestimated proportion, HF is caused by Mendelian inherited forms of myocardial disease. The genetic background of these genetic conditions is a matter of intensive research that is already shedding light onto the genetics of common sporadic forms of HF. In this review, we briefly review the insights provided by candidate gene and genome-wide association approaches in common HF and then describe the main genetic causes of inherited heart muscle disease. Finally we present the current challenges and future research needs for both forms of HF. This article is part of a Special Issue entitled: Heart failure pathogenesis and emerging diagnostic and therapeutic interventions.