Angiotensin-converting enzyme inhibition in cardiovascular disease: evidence with perindopril

Exploration of multifaceted molecular mechanism of angiotensin-converting enzyme 2 (ACE2) in pathogenesis of various diseases

Angiotensin converting enzyme 2 (ACE2) is a homolog of ACE (a transmembrane bound dipeptidyl peptidase enzyme). ACE2 converts angiotensinogen to the heptapeptide angiotensin-(1-7). ACE2 and its product, angiotensin-(1-7), have counteracting effects against the adverse actions of other members of renin-angiotensin system (RAS). ACE2 and its principal product, angiotensin-(1-7), were considered an under recognized arm of the RAS. The COVID-19 pandemic brought to light this arm of RAS with special focus on ACE2. Membrane bound ACE2 serves as a receptor for SARS-CoV-2 viral entry through spike proteins. Apart from that, ACE2 is also involved in the pathogenesis of various other diseases like cardiovascular disease, cancer, respiratory diseases, neurodegenerative diseases and infertility. The present review focuses on the molecular mechanism of ACE2 in neurodegenerative diseases, cancer, cardiovascular disease, infertility and respiratory diseases, including SARS-CoV-2. This review summarizes unveiled roles of ACE2 in the pathogenesis of various diseases which further provides intriguing possibilities for the use of ACE2 activators and RAS modulating agents for various diseases.

Pathophysiology of cough with angiotensin-converting enzyme inhibitors: How to explain within-class differences?

Angiotensin converting enzyme inhibitors (ACEi) have consistently demonstrated improved survival and reduced risk of major cardiovascular events, across the spectrum of cardiovascular disease, including hypertension, coronary artery disease, myocardial infarction, and heart failure. The cardioprotective effects of ACEi result from inhibiting the conversion of angiotensin I to angiotensin II, and inhibition of bradykinin degradation. They are generally well tolerated but may cause the onset of a dry cough in some patients. This review presents current evidence on the incidence and mechanisms of cough associated with ACEi use, and then considers how to manage ACEi-related cough in clinical practice. The incidence of ACEi-induced cough in the published literature varies widely due to heterogeneity in the source data and lack of adequate controls. Incidence also varies among individual ACEi with agents such as perindopril, which has a high tissue ACE affinity, associated with a lower rate of cough. Evidence from real-world studies shows that the incidence of ACEi-associated cough is lower than rates reported in clinical trials. Patients who experience any dry cough are often switched to angiotensin- receptor blockers or other classes of antihypertensive drugs, regardless of cough severity. To avoid inappropriate discontinuation of ACEi in clinical practice, an alternative approach in patients with persistent cough is to perform a challenge/re-challenge to determine if re-introduction of ACEi is associated with recurrence of symptoms. Incidence of cough should not be considered a class effect for ACEi, and the patient may benefit by a switch from one ACEi to another. Every effort should be made to enable patients to continue ACEi therapy to reduce adverse cardiovascular outcomes and improve survival.

Exploring and modeling the ion mobility spectrometry of perindopril: Example of protonation-dissociation reactions in large molecules

The current research is constructed for considering the chemical ionization and dissociation of perindopril in the positive mode of corona discharge ion mobility spectrometry. Four product ion peaks are observed in the ion mobility spectrum of perindopril erbumine at the cell temperature of 473 K. These peaks are assigned through the obtained intensity variation analysis in the ion mobility spectra over the elapsed time accompanied by the calculations backed by the validated density functional theory (DFT). In this regard, the most stable ionic species associated with each peak and the corresponding reliable generation pathways are found by the well-confirmed meta hybrid density functional method, M06-2X. The peaks are assigned to the protonated perindopril and its dissociation products, including counter ion and the related fragment ions. However, the structures of the neutral perindopril in the gas phase are thoroughly assessed to find a more stable one. The predicted chemical ionization products by the theory are in excellent agreement with our presented experiment here. Theoretical evaluations demonstrated that the production of a fragment by dissociation process occurs when perindopril gets a proton from the ionization region. Also, without protons, there is no dissociation process. Therefore, our mechanism investigated here is the proton transfer one. All possible sites of perindopril are considered theoretically for protonation along with their possible reactions. In addition to the computed PES, the assigned ions for obtained spectra are confirmed by the computed equilibrium constants and rate constants. Our theoretical results show that the peak of the main fragment is for M-CH₃ CH₂ OH produced by a reaction pathway involving no barrier. This study opens new perspectives in interpreting large molecules spectra for future studies.

Mechanisms for the development of heart failure and improvement of cardiac function by angiotensin-converting enzyme inhibitors

Angiotensin-converting enzyme (ACE) inhibitors, which prevent the conversion of angiotensin I to angiotensin II, are well-known for the treatments of cardiovascular diseases, such as heart failure, hypertension and acute coronary syndrome. Several of these inhibitors including captopril, enalapril, ramipril, zofenopril and imidapril attenuate vasoconstriction, cardiac hypertrophy and adverse cardiac remodeling, improve clinical outcomes in patients with cardiac dysfunction and decrease mortality. Extensive experimental and clinical research over the past 35 years has revealed that the beneficial effects of ACE inhibitors in heart failure are associated with full or partial prevention of adverse cardiac remodeling. Since cardiac function is mainly determined by coordinated activities of different subcellular organelles, including sarcolemma, sarcoplasmic reticulum, mitochondria and myofibrils, for regulating the intracellular concentration of Ca2+ and myocardial metabolism, there is ample evidence to suggest that adverse cardiac remodelling and cardiac dysfunction in the failing heart are the consequence of subcellular defects. In fact, the improvement of cardiac function by different ACE inhibitors has been demonstrated to be related to the attenuation of abnormalities in subcellular organelles for Ca2+-handling, metabolic alterations, signal transduction defects and gene expression changes in failing cardiomyocytes. Various ACE inhibitors have also been shown to delay the progression of heart failure by reducing the formation of angiotensin II, the development of oxidative stress, the level of inflammatory cytokines and the occurrence of subcellular defects. These observations support the view that ACE inhibitors improve cardiac function in the failing heart by multiple mechanisms including the reduction of oxidative stress, myocardial inflammation and Ca2+-handling abnormalities in cardiomyocytes.

A Proline-Based Tectons and Supramolecular Synthons for Drug Design 2.0: A Case Study of ACEI

Proline is a unique, endogenous amino acid, prevalent in proteins and essential for living organisms. It is appreciated as a tecton for the rational design of new bio-active substances. Herein, we present a short overview of the subject. We analyzed 2366 proline-derived structures deposited in the Cambridge Structure Database, with emphasis on the angiotensin-converting enzyme inhibitors. The latter are the first-line antihypertensive and cardiological drugs. Their side effects prompt a search for improved pharmaceuticals. Characterization of tectons (molecular building blocks) and the resulting supramolecular synthons (patterns of intermolecular interactions) involving proline derivatives, as presented in this study, may be useful for in silico molecular docking and macromolecular modeling studies. The DFT, Hirshfeld surface and energy framework methods gave considerable insight into the nature of close inter-contacts and supramolecular topology. Substituents of proline entity are important for the formation and cooperation of synthons. Tectonic subunits contain proline moieties characterized by diverse ionization states: -N and -COOH(-COO-), -N+ and -COOH(-COO-), -NH and -COOH(-COO-), -NH+ and -COOH(-COO-), and -NH2+ and -COOH(-COO-). Furthermore, pharmacological profiles of ACE inhibitors and their impurities were determined via an in silico approach. The above data were used to develop comprehensive classification, which may be useful in further drug design studies.

Advantages of prophylactic versus conventionally scheduled heart failure therapy in an experimental model of doxorubicin-induced cardiomyopathy

Background

Chemotherapy-induced left ventricular dysfunction represents a major clinical problem, which is often only recognised at an advanced stage, when supportive therapy is ineffective. Although an early heart failure treatment could positively influence the health status and clinical outcome, there is still no evidence of routine prophylactic cardioprotection for the majority of patients without previous cardiovascular history awaiting potentially cardiotoxic chemotherapy. In this study, we set out to investigate whether a prophylactic cardioprotective therapy relative to a conventionally scheduled heart failure treatment is more effective in preventing cardiotoxicity in a rodent model of doxorubicin (DOX)-induced cardiomyopathy.

Methods

Male Wistar rats (n = 7–11 per group) were divided into 4 subgroups, namely negative controls receiving intravenous saline (CON), positive controls receiving intravenous DOX (6 cycles; D-CON), and DOX-treated animals receiving either prophylactic (PRE, started 1 week before DOX) or conventionally applied (POST, started 1 month after DOX) combined heart failure therapy of oral bisoprolol, perindopril and eplerenone. Blood pressure, heart rate, body weight and echocardiographic parameters were monitored in vivo, whereas myocardial fibrosis, capillarisation, ultrastructure, myofilament function, apoptosis, oxidative stress and mitochondrial biogenesis were studied in vitro.

Results

The survival rate in the PRE group was significantly improved compared to D-CON (p = 0.0207). DOX increased the heart rate of the animals (p = 0.0193), while the blood pressure (p ≤ 0.0105) and heart rate (p = 0.0029) were significantly reduced in the PRE group compared to D-CON and POST. The ejection fraction remained preserved in the PRE group compared to D-CON or POST (p ≤ 0.0237), while none of the treatments could prevent the DOX-induced increase in the isovolumetric relaxation time. DOX decreased the rate of the actin-myosin cross-bridge cycle, irrespective of any treatment applied (p ≤ 0.0433). The myocardium of the D-CON and POST animals displayed pronounced ultrastructural damage, which was not apparent in the PRE group (p ≤ 0.033). While the DOX-induced apoptotic activity could be reduced in both the PRE and POST groups (p ≤ 0.0433), no treatment was able to prevent fibrotic remodelling or the disturbed mitochondrial biogenesis.

Conclusion

For attenuating DOX-induced adverse myocardial effects, prophylactic cardioprotection has many advantages compared to a late-applied treatment.

Electronic supplementary material

The online version of this article (10.1186/s12967-019-1978-0) contains supplementary material, which is available to authorized users.

Kallikrein-kinin system as the dominant mechanism to counteract hyperactive renin-angiotensin system

The renin-angiotensin system (RAS) generates, maintains, and makes worse hypertension and cardiovascular diseases (CVDs) through its biologically active component angiotensin II (Ang II), that causes vasoconstriction, sodium retention, and structural alterations of the heart and the arteries. A few endogenous vasodilators, kinins, natriuretic peptides, and possibly angiotensin (1-7), exert opposite actions and may provide useful therapeutic agents. As endothelial autacoids, the kinins are potent vasodilators, active natriuretics, and protectors of the endothelium. Indeed, the kallikrein-kinin system (KKS) is considered the dominant mechanism for counteracting the detrimental effects of the hyperactive RAS. The 2 systems, RAS and KKS, are controlled by the angiotensin-converting enzyme (ACE) that generates Ang II and inactivates the kinins. Inhibitors of ACE can reduce the impact of Ang II and potentiate the kinins, thus contributing to restore the cardiovascular homeostasis. In the last 20 years, ACE-inhibitors (ACE-Is) have become the drugs of first choice for the treatments of the major CVDs. ACE-Is not only reduce blood pressure, as sartans also do, but by protecting and potentiating the kinins, they can reduce morbidity and mortality and improve the quality of life for patients with CVDs. This paper provides a brief review of the literature on this topic.

Perindopril Induces TSP-1 Expression in Hypertensive Patients with Endothelial Dysfunction in Chronic Treatment

Thrombospondin-1 (TSP-1) is a potent endogenous inhibitor of both physiological and pathological angiogenesis, widely studied as a target in drug development for treating cancer. Several studies performed in the cardiovascular field on TSP-1 are contradictory, the role of TSP-1 in the physiopathology of cardiovascular disorders (CVDs) being, for the moment, incompletely understood and may be due to the presence of several domains in its structure which can stimulate many cellular receptors. It has been reported to inhibit NO-mediated signaling and to act on the angiogenesis, tissue perfusion, endothelial cell proliferation, and homeostasis, so we aimed to quantify the effect Perindopril has on TSP-1 plasma levels in hypertensive patients with endothelial dysfunction in comparison with other antihypertensive drugs, such as beta blockers, calcium channel blockers, and diuretics, in a chronic treatment. As a conclusion, patients under treatment with Perindopril had increased plasma levels of TSP-1 compared with other hypertensive patients and with the control group. The results of this study confirms the pleiotropic properties of Perindopril: anti-proliferative, anti-inflammatory, with effects showed by quantifying a single biomarker: TSP-1.

Comparative Solid-State Stability of Perindopril Active Substance vs. Pharmaceutical Formulation

This paper presents the results obtained after studying the thermal stability and decomposition kinetics of perindopril erbumine as a pure active pharmaceutical ingredient as well as a solid pharmaceutical formulation containing the same active pharmaceutical ingredient (API). Since no data were found in the literature regarding the spectroscopic description, thermal behavior, or decomposition kinetics of perindopril, our goal was the evaluation of the compatibility of this antihypertensive agent with the excipients in the tablet under ambient conditions and to study the effect of thermal treatment on the stability of perindopril erbumine. ATR-FTIR (Attenuated Total Reflectance Fourier Transform Infrared) spectroscopy, thermal analysis (thermogravimetric mass curve (TG-thermogravimetry), derivative thermogravimetric mass curve (DTG), and heat flow (HF)) and model-free kinetics were chosen as investigational tools. Since thermal behavior is a simplistic approach in evaluating the thermal stability of pharmaceuticals, in-depth kinetic studies were carried out by classical kinetic methods (Kissinger and ASTM E698) and later with the isoconversional methods of Friedman, Kissinger-Akahira-Sunose and Flynn-Wall-Ozawa. It was shown that the main thermal degradation step of perindopril erbumine is characterized by activation energy between 59 and 69 kJ/mol (depending on the method used), while for the tablet, the values were around 170 kJ/mol. The used excipients (anhydrous colloidal silica, microcrystalline cellulose, lactose, and magnesium stearate) should be used in newly-developed generic solid pharmaceutical formulations, since they contribute to an increased thermal stability of perindopril erbumine.

Critical insights into the beneficial and protective actions of the kallikrein-kinin system

Hypertension is characterized by an imbalance between the renin-angiotensin system (RAS) and the kallikrein-kinin system (KKS). Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II AT-1 receptor antagonists (also known as sartans or ARBs) are potent modulators of these systems and are highly effective as first-line treatments for hypertension, diabetic nephropathies, and diseases of the brain and coronary arteries. However, these agents are mechanistically distinct and should not be considered interchangeable. In this mini-review, we provide novel insights into the often neglected roles of the KKS in the beneficial, protective, and reparative actions of ACEIs. Indeed, ACEIs are the only antihypertensive drugs that properly reduce the imbalance between the RAS and the KKS, thereby restoring optimal cardiovascular homeostasis and significantly reducing morbidity and the risk of all-cause mortality among individuals affected by hypertension and other cardiovascular diseases.

RAS inhibitors' dose-dependent efficacy: myth or reality?

OBJECTIVE

Treatment of hypertension remains challenging in clinical practice. One major problem is incorrect utilization of the principal drug classes. Drugs from each class are currently used in accordance with an assumption that the blood pressure (BP) lowering effect is dose dependent. While this is true for most drugs, it is not appropriate for all drugs that block the renin-angiotensin system (RAS).

METHODS

This review is based on a PubMed/Cochrane database search for articles on the dose-dependent effect of RAS blockers on BP and cardiovascular protection.

RESULTS

Of the RAS blockers, most angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) have a flat dose-response curve for BP decrease, meaning an increase in dose prolongs duration of action, but does not yield greater potency. Perindopril is the only ACE inhibitor to show a real dose-response curve for BP decrease. While the effectiveness of RAS blockers on target organ damage is dose dependent and at least partially unrelated to BP control, there is evidence that the only way to obtain a beneficial effect is to use them at full dose. Thus, RAS blockers need to be used at the correct dose, based on the results of controlled clinical trials and meta-analysis. Furthermore, for all-cause mortality, ACE inhibitors have been shown to be better than ARBs, a specific efficacy supported by perindopril-based studies including ASCOT-BPLA (the Anglo-Scandinavian Cardiac Outcomes Trial-BP Lowering Arm), ADVANCE (the Action in Diabetes and Vascular disease: PreterAx and DiamicroN-MR Controlled Evaluation trial) and HYVET (HYpertension in the Very Elderly Trial).

CONCLUSION

In hypertensive patients, a strategy based on ACE inhibitors with dose-dependent efficacy such as perindopril as optimal treatment should lead both to improved BP control and to a better protection from target organ damage, thereby reducing the incidence of cardiovascular events.

RAAS inhibition and mortality in hypertension

The renin-angiotensin-aldosterone system (RAAS) regulates the body's hemodynamic equilibrium, circulating volume, and electrolyte balance, and is a key therapeutic target in hypertension, the world's leading cause of premature mortality. Hypertensive disorders are strongly linked with an overactive RAAS, and RAAS inhibitors, like angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs), are routinely used to treat high blood pressure (BP). BP reduction is one of the main goals of current European hypertension guidelines. Oral ACE inhibitors, the oldest category of RAAS inhibitor, were commercially released over 30 years ago in the early 1980s, over a decade before the first ARBs became available. The introduction of ACE inhibitors heralded major changes in the way hypertension and cardiovascular disease were treated. Although the decision of the medical community to replace older ACE inhibitors with more modern ARBs in the 1990s was debatable, it did nevertheless allow scientists to learn more about the angiotensin receptors involved in RAAS stimulation. This and much else of value have been discovered since RAAS inhibitors first became available, but some surprising gaps in our knowledge exist. Until recently, the effect of RAAS inhibition on mortality in hypertension was unknown. This question was recently addressed by a meta-analysis of randomized controlled trials in populations who received contemporary antihypertensive medication. The results of this meta-analysis have helped elucidate the long-term consequences of treatment with RAAS inhibitors on mortality in hypertension. This article will consider the differences between RAAS inhibitors in terms of pharmacological and clinical effects and analyze the impact of the main types of RAAS inhibitor, ACE inhibitors and ARBs, on mortality reduction in hypertensive patients with reference to this latest meta-analysis.

Genetic influences of angiotensin-converting enzyme inhibitor response: an opportunity for personalizing therapy?

The angiotensin-converting enzyme (ACE) inhibitors are a cornerstone drug therapy in the current treatment of patients with hypertension, stable coronary artery disease and heart failure. Individualizing therapy of ACE inhibitors with clinical risk factors in low-risk patients with stable coronary artery disease is not feasible. The concept of pharmacogenetics, by studying patient factors more individually, offers a first glimpse in the quest for the 'holy grail' of personalized medicine. As such, genetic targets in the direct pharmacodynamic pathway of ACE inhibitors, the renin-angiotensin-aldosterone system, is a plausible candidate for such an approach. In the past few decades, results of pharmacogenetic studies were scarce and inconsistent. However, recently the first reports of larger pharmacogenetic studies are now confirming that the 'pharmacogenetic approach' might be feasible in the future. The current review focuses on the recent developments in pharmacogenetic research in response to ACE inhibitors in patients with stable coronary artery disease.

Perindoprilat monohydrate

The title compound [systematic name: (1S)-2-((S)-{1-[(2S,3aS,7aS)-2-carboxyoctahydro-1H-indol-1-yl]-1-oxopropan-2-yl}azaniumyl)pentanoate monohydrate], C(17)H(28)N(2)O(5)·H(2)O, (I)·H(2)O, the active metabolite of the antihypertensive and cardiovascular drug perindopril, was obtained during polymorphism screening of perindoprilat. It crystallizes in the chiral orthorhombic space group P2(1)2(1)2(1), the same as the previously reported ethanol disolvate [Pascard, Guilhem, Vincent, Remond, Portevin & Laubie (1991). J. Med. Chem. 34, 663-669] and dimethyl sulfoxide hemisolvate [Bojarska, Maniukiewicz, Sieroń, Fruziński, Kopczacki, Walczyński & Remko (2012). Acta Cryst. C68, o341-o343]. The asymmetric unit of (I)·H(2)O contains one independent perindoprilat zwitterion and one water molecule. These interact via strong hydrogen bonds to give a cyclic R(2)(2)(7) synthon, which provides a rigid molecular conformation. The geometric parameters of all three forms are similar. The conformations of the perhydroindole group are almost identical, but the n-alkyl chain has conformational freedom. A three-dimensional hydrogen-bonding network of O-H···O and N-H···O interactions is observed in the crystal structure of (I)·H(2)O, similar to the other two solvates, but because of the presence of different solvents the three crystal structures have diverse packing motifs. All three solvatomorphs are additionally stabilized by nonclassical weak C-H···O contacts.

Individualised therapy of angiotensin converting enzyme (ACE) inhibitors in stable coronary artery disease: overview of the primary results of the PERindopril GENEtic association (PERGENE) study

In patients with stable coronary artery disease (CAD) without overt heart failure, ACE inhibitors are among the most commonly used drugs as these agents have been proven effective in reducing the risk of cardiovascular events. Considerable individual variations in the blood pressure response to ACE inhibitors are observed and as such heterogeneity in clinical treatment effect would be likely as well. Assessing the consistency of treatment benefit is essential for the rational and cost-effective prescription of ACE inhibitors. Information on heterogeneities in treatment effect between subgroups of patients could be used to develop an evidence-based guidance for the installation of ACE-inhibitor therapy. Obviously, therapy should only be applied in those patients who most likely will benefit. Attempts to develop such treatment guidance by using clinical characteristics have been unsuccessful. No heterogeneity in risk reduction by ACE inhibitors has been observed in relation to relevant clinical characteristics. A new approach to such 'guided-therapy' could be to integrate more patient-specific characteristics such as the patients' genetic information. If proven feasible, pharmacogenetic profiling could optimise patients' benefit of treatment and reduce unnecessary treatment of patients. Cardiovascular pharmacogenetic research of ACE inhibitors in coronary artery disease patients is in a formative stage and studies are limited. The PERGENE study is a large pharmacogenetic substudy of the EUROPA trial, aimed to assess the achievability of pharmacogenetic profiling. We provide an overview of the main results of the PERGENE study in terms of the genetic determinants of treatment benefit and blood pressure response. The main results of the PERGENE study show a pharmacogenetic profile related to the treatment benefit of perindopril identifying responders and non-responders to treatment.

Effect of a centrally active angiotensin converting enzyme inhibitor, perindopril, on cognitive performance in chronic cerebral hypo-perfusion rats

We have previously demonstrated that perindopril, an angiotensin-converting enzyme (ACE) inhibitor, ameliorated the cognitive deficits in Alzheimer's disease model animals, independently of its anti-hypertensive effect. In this study, we again investigated the effects of perindopril on cognitive function in a vascular dementia model animal, comparing it with other ACE inhibitors. We also determined ACE activity in the brain and extracellular acetylcholine (ACh) concentration in the perirhinal cortex in order to elucidate the mechanism(s) responsible for the effects of these ACE inhibitors on cognitive function. Perindopril was suggested to be more centrally active than imidapril and enalapril, in consideration of the relative distribution of their active metabolites in the brain. This property was at least partially attributed to the lipophilicity of the compound. While the 3 day treatment with perindopril, imidapril or enalapril lowered blood pressure to the same level in spontaneous hypertensive rats, only perindopril reversed the decline in the recognition index in chronic cerebral hypo-perfusion rats, regarded as an animal model of vascular dementia, during an object recognition task. Using the same dosing regimen, perindopril inhibited the brain ACE activities of rats more than imidapril or enalapril. Moreover, a single treatment with perindopril enhanced the extracellular level of ACh in the perirhinal cortex of normal rats. Therefore, we confirmed that only centrally active ACE inhibitors, such as perindopril, can inhibit the ACE in the brain, augmenting cholinergic neurotransmission and thereby ameliorating cognitive impairment in the animal model of vascular dementia.

Secondary prevention of CAD with ACE inhibitors: a struggle between life and death of the endothelium

Angiotensin-converting enzyme (ACE) inhibitors improve outcomes in patients with coronary artery disease (CAD), heart failure, and hypertension. This short review examines clinical evidence for such effects and the underlying mechanism of action. One potential mode of action for ACE inhibitors in CAD is blood pressure reduction. However, recent data suggest that the effects of ACE inhibitors on the endothelium may also be relevant in attenuating the progression of atherosclerosis. In CAD, chronic overexpression of tissue ACE disrupts the angiotensin II/bradykinin balance with a net result of endothelial dysfunction, mainly due to an increased rate of apoptosis. An imbalance between endothelial apoptosis (death) and its renewal from the bone marrow (life) causes discontinuity of the endothelial layer, favoring the initiation and progression of a biochemical sequence that leads to atherosclerosis, plaque rupture, and eventually acute coronary syndromes. There is clinical and experimental evidence that ACE inhibition improves the life and death cycle of the endothelium. By restoring the bradykinin/angiotensin II balance, ACE inhibition reduces the rate of endothelial apoptosis and experimental results suggest that ACE inhibition can also improve the production and mobilization of endothelial progenitor cells from bone marrow. We report our experience in this context with perindopril.

Tailored therapy of ACE inhibitors in stable coronary artery disease: pharmacogenetic profiling of treatment benefit

Angiotensin-converting enzyme (ACE) inhibitors are among the most commonly used drugs in stable coronary artery disease as these agents have been proven to be effective for reducing the risk of cardiovascular morbidity and mortality. As with other drugs, individual variation in treatment benefit is likely. Such heterogeneity could be used to target ACE-inhibitor therapy to those patients most likely to benefit from treatment. However, prior attempts to target ACE-inhibitor therapy to those patients who are most likely to benefit of such prophylactic treatment in secondary prevention using clinical characteristics or the level of baseline risk appeared not to be useful. A new approach of 'tailored therapy' could be to integrate more patient-specific characteristics, such as the genetic information of patients. Pharmacogenetic research of ACE inhibitors in coronary artery disease patients is at a formative stage, and studies are limited. The Perindopril Genetic association (PERGENE) study is a large pharmacogenetic substudy of the randomized placebo-controlled European trial On Reduction of Cardiac Events with Perindopril in Patients with Stable Coronary Artery disease (EUROPA) trial, aimed to assess the feasibility of pharmacogenetic profiling of ACE-inhibitor therapy by perindopril. This article summarizes the recent findings of the PERGENE study and pharmacogenetic research of the treatment benefit of perindopril in stable coronary artery disease.

Rationale for the use of a fixed-dose combination in the management of hypertension: efficacy and tolerability of lercanidipine/enalapril

Hypertension, a significant factor in the development of cerebrovascular disorders, heart disease and renal failure, is a common disorder worldwide. Despite the availability of a wide range of antihypertensive agents, almost two-thirds of hypertensive patients have poorly controlled blood pressure (BP). Numerous clinical trials have shown that most patients require at least two antihypertensive agents to achieve adequate BP control and associated significant reductions in cardiovascular morbidity and mortality. Combination therapy using two drugs with different, complementary mechanisms of action achieves better efficacy and tolerability outcomes than treatment with either component drug alone. When such a combination is administered as a fixed-dose formulation, other benefits, such as improved compliance and potentially lower costs, are also likely. The good efficacy and tolerability of the combination of a calcium channel antagonist and an angiotensin-converting enzyme inhibitor is well established, and this combination is recommended by European Society of Hypertension/European Society of Cardiology guidelines as a first choice in high-risk hypertensive patients, including those with type 2 diabetes mellitus. Lercanidipine/enalapril is a promising example of a fixed-dose combination of these drug classes. In clinical trials in hypertensive patients, including those with type 2 diabetes, lercanidipine/enalapril improved BP to a greater extent than either drug as monotherapy (in patients who were previous non-responders to lercanidipine or enalapril) or the combination of lercanidipine/hydrochlorothiazide, and was equally well tolerated. Further studies are required to evaluate the cardiovascular protective effects of lercanidipine/enalapril.

Human epicardial adipokine messenger RNAs: comparisons of their expression in substernal, subcutaneous, and omental fat

We compared the gene expression of inflammatory and other proteins by real-time quantitative polymerase chain reaction in epicardial, substernal (mediastinal) and subcutaneous sternal, upper abdominal, and leg fat from coronary bypass patients and omental (visceral) fat from extremely obese women undergoing bariatric surgery. We hypothesized that (1) epicardial fat would exhibit higher expression of inflammatory messenger RNAs (mRNAs) than substernal and subcutaneous fat and (2) epicardial mRNAs would be similar to those in omental fat. Epicardial fat was clearly different from substernal fat because there was a far higher expression of haptoglobin, prostaglandin D(2) synthase, nerve growth factor beta, the soluble vascular endothelial growth factor receptor (FLT1), and alpha1 glycoprotein but not of inflammatory adipokines such as monocyte chemoattractant protein-1, interleukin (IL)-8, IL-1beta, tumor necrosis factor alpha, serum amyloid A, plasminogen activator inhibitor-1, or adiponectin despite underlying coronary atherosclerosis. However, the latter inflammatory adipokines as well as most other mRNAs were overexpressed in epicardial fat as compared with the subcutaneous depots except for IL-8, fatty acid binding protein 4, the angiotensin II receptor 1, IL-6, and superoxide dismutase-2. Relative to omental fat, about one third of the genes were expressed at the same levels, whereas monocyte chemoattractant protein-1, cyclooxygenase-2, plasminogen activator inhibitor-1, IL-1beta, and IL-6 were expressed at far lower levels in epicardial fat. In conclusion, epicardial fat does not appear to be a potentially more important source of inflammatory adipokines than substernal mediastinal fat. Furthermore, the expression of inflammatory cytokines such as IL-6 and IL-1beta is actually higher in omental fat from obese women without coronary atherosclerosis. The data do not support the hypothesis that most of the inflammatory adipokines are expressed at high levels in epicardial fat of humans.

[Angiotensin converting enzyme inhibitors and calcium antagonists: a synergistic action for a better prevention of cardiovascular events]

Treatment of hypertension increasingly requires association of drugs. Among them, the association of calcium antagonists with angiotensin converting enzyme inhibitors is a new tempting approach since the two pharmaceutical classes have synergistic effects on blood pressure lowering and target organ protection whereas their effect is antagonistic for adverse events. Numerous large randomized clinical trials have validated this treatment strategy, and new fixed association are being developed. They apply to hypertensive patients, but also to coronary artery disease patients and more generally speaking to high cardiovascular risk subjects.

Early use of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers: evidence from clinical trials

Following acute myocardial infarction, patients are at increased risk of developing heart failure, which is more prevalent in those with reduced ventricular systolic function. Activation of the renin-angiotensin-aldosterone system, which occurs early after myocardial injury, plays a central role in the pathogenesis of subsequent cardiac structural and functional abnormalities. The early use of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers has been tested in several large randomized clinical trials. The results of these trials show that this treatment strategy reduces the incidence of heart failure and mortality in the postmyocardial infarction patient. The magnitude of benefit is larger in patients with high-risk features, particularly those with large infarct size and the presence of heart failure or left ventricular systolic dysfunction at the time of myocardial injury. Careful use of these agents is essential in avoiding clinically significant hypotension in the critical period.

Perindopril for control of blood pressure in patients with hypertension and other cardiovascular risk factors: an open-label, observational, multicentre, general practice-based study

BACKGROUND AND OBJECTIVES

Hypertension, one of the major treatable cardiovascular (CV) risk factors, usually occurs in association with other major risk factors. As well as providing rapid blood pressure (BP) goal attainment, antihypertensive therapy should also provide reductions in CV events and mortality in a wide range of patients. For this, higher dosages and combinations of antihypertensive agents are often required. ACE inhibitors are recommended as first-line agents for control of hypertension in patients with additional CV risk factors. The PEACH (Perindopril's Effect At Controlling Hypertension) study was a community-based study performed to evaluate the effectiveness and safety of high-dose perindopril in patients with mild-to-moderate hypertension and additional risk factors for CV disease.

METHODS

This was an open-label, multicentre observational study conducted in Canadian general practice clinics. The study assessed the efficacy and tolerability of perindopril given once daily for 10 weeks uptitrated to the maximal recommended dose of perindopril as required for BP control in newly diagnosed or previously treated patients with uncontrolled mild to moderate hypertension and >or=1 additional risk factor. Patients not achieving target BP after 2 weeks of therapy were uptitrated from perindopril 4 mg to perindopril 8 mg once daily. Efficacy endpoints included reduction in systolic (SBP) and diastolic (DBP) BP and BP control. Tolerability assessments included adverse effects and physicians' assessment of tolerability. The number of missed doses was also recorded.

RESULTS

Overall, 2220 patients with hypertension and >or=1 other risk factor were prescribed perindopril at 291 centres; 51.9% were male, 78.3% Caucasian, 12.8% Asian, 36.2%>or=65 years of age and 34.5% had uncontrolled BP despite previous antihypertensive treatment. Compared with previously treated patients, treatment-naive patients had fewer risk factors, and a higher proportion were Asian (p<0.05 for all comparisons). Most patients (76%) had 1-2 risk factors. Perindopril produced significant SBP/DBP reductions at 2 and 10 weeks (-15.8/-8.0 and -21.1/-11.0 mmHg, respectively). Overall, at week 10, BP control rate was 53.6%, better than at week 2 in the overall cohort and in all subgroups. Uptitration to high-dose perindopril to achieve BP control was required in 46% of patients with one additional risk factor compared with 64% of patients with >or=4 additional risk factors. These results demonstrate that the more risk factors the patient has, the greater the need for high-dose perindopril to achieve BP control. Perindopril was well tolerated as indicated by the high proportion of physicians (95.9%) reporting 'good' to 'excellent' tolerability at week 10.

CONCLUSION

In this community-based clinical practice trial, up to 10 weeks' perindopril therapy, uptitrated to the maximal recommended dose as required for BP control, significantly reduced SBP/DBP in patients with mild-to-moderate hypertension and additional CV risk factors. Patients with more risk factors were more likely to require high-dose perindopril.

Optimizing the treatment of hypertension and stable coronary artery disease: clinical evidence for fixed-combination perindopril/amlodipine

BACKGROUND

Optimized management of hypertension and coronary artery disease (CAD) improves cardiovascular risk and outcomes, and prevents complications. This article reviews evidence for the fixed combination of the angiotensin-converting enzyme (ACE) inhibitor perindopril and the calcium channel blocker amlodipine.

METHODS

A literature search was performed in PubMed/MEDLINE to identify articles published in English between 1988 and March 2008 describing clinical trials, particularly outcome trials, or mechanisms of therapeutic action relevant to the use of combination therapy in patients with hypertension or stable coronary artery disease with an ACE inhibitor (perindopril) and a calcium channel blocker (amlodipine).

FINDINGS

Clinical trials indicate that this combination may have a positive impact on cardiovascular mortality and morbidity in hypertensive individuals. The two complementary mechanisms of action appear to work in synergy, leading to more efficient blood pressure lowering, improved fibrinolytic function, and reduction of secondary effects. This also represents a simplified management strategy for stable CAD. Perindopril has proven efficacy in the prevention of cardiovascular events and mortality in CAD patients, while amlodipine is widely used in the symptomatic management of CAD. Both aspects of guideline-recommended management of CAD are therefore addressed in a single tablet.

CONCLUSIONS

The clinical evidence for fixed-combination perindopril/amlodipine indicates it as a credible option for the optimization of the management of hypertension and CAD.

Angiotensin-converting enzyme (ACE) inhibitors have different selectivity for bradykinin binding sites of human somatic ACE

The angiotensin-converting enzyme (ACE) has two natural substrates and two catalytic domains: one cleaving angiotensin I and one inactivating bradykinin. The aim of this study was to investigate the comparative binding affinity of ACE inhibitors for the two binding sites of human endothelial ACE. In vitro binding assays were performed to test the ability of bradykinin, angiotensin I, or various ACE inhibitors (enalaprilat, perindoprilat, quinaprilat, ramiprilat, and trandolaprilat) to displace a saturating concentration of [(125)I]351A, a radiolabeled lisinopril analogue, from ACE binding sites. The calculated IC(50) values for the ACE inhibitors were in the nanomolar range, while those for the natural substrates were in the micromolar range. The bradykinin/angiotensin I selectivity ratios calculated from double displacement experiments were: perindoprilat, 1.44; ramiprilat, 1.16; quinaprilat, 1.09; trandolaprilat, 1.08; enalaprilat, 1.00. The ACE inhibitors generally had higher affinity for the bradykinin than the angiotensin I binding sites, supporting the idea that these agents are primarily inhibitors of bradykinin degradation, and secondarily inhibitors of angiotensin II production. Perindoprilat had the highest selectivity for bradykinin versus angiotensin I binding sites, and enalaprilat has the lowest. These results indicate that there are differences in the affinity of ACE inhibitors toward sites for bradykinin degradation, which could lead to differences in efficacy in cardiovascular disease.

Perindopril arginine: benefits of a new salt of the ACE inhibitor perindopril

BACKGROUND

The efficacy of the angiotensin-converting enzyme (ACE) inhibitor perindopril in the treatment of hypertension, stable coronary artery disease, and heart failure is well established. The reduced stability of the current salt, perindopril-tert-butylamine, in extreme climatic conditions has prompted research into more stable compounds. This article presents stability and bioequivalence results for a new L-arginine salt of perindopril.

METHODS

Drug stability studies were performed on nonsalified perindopril, perindopril-tert-butylamine, and perindopril arginine in closed and open containers. The bioequivalence of perindopril arginine was tested in 36 healthy male volunteers in an open-label, randomized, two-period, crossover pharmacokinetic study. A consumer study was carried out in 120 patients to assess preference for a simplified packaging using a high-density polyethylene canister designed for distribution to all climatic zones.

RESULTS AND DISCUSSION

Perindopril arginine is 50% more stable than perindopril-tert-butylamine, which increases the shelf life from 2 to 3 years. At the revised dosage (perindopril arginine 5-10 mg/day corresponds to perindopril-tert-butylamine 4-8 mg/day), the new salt is equivalent in terms of pharmacokinetics, efficacy, safety, and acceptability. The consumer studies indicate a preference for the new packaging, with 62% of patients nominating the canister as better than the blister packs.

CONCLUSION

The new perindopril arginine salt is equivalent to perindopril-tert-butylamine and more stable, and can be distributed to climatic zones III and IV without the need for specific packaging. The patient preference for the new packaging could have positive implications for compliance.

ACE inhibition in hypertension: focus on perindopril

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.

Perindopril versus Angiotensin II Receptor Blockade in Hypertension and Coronary Artery Disease

The renin-angiotensin-aldosterone system (RAAS) is now known to play a key role in the pathogenesis of hypertension and a range of other cardiovascular diseases. Two groups of drugs, the ACE inhibitors and angiotensin II type 1 receptor antagonists (angiotensin receptor blockers [ARBs]) have been developed with the aim of improving clinical outcomes by regulating the RAAS in patients with cardiovascular disease. Initial assumptions were that these two drug types might be interchangeable, but ongoing research has revealed differences between them in terms of pharmacology and outcomes in clinical trials. Although both groups of drugs lower blood pressure, studies of the ACE inhibitor perindopril have revealed preservation of beneficial vascular and endothelial effects mediated by bradykinin and nitric oxide. The selective blockade exerted by ARBs is not associated with these effects. Furthermore, examination of clinical endpoints in major clinical trials has provoked discussion about outcomes comparing ACE inhibitors and ARBs, with recent debate focusing on the incidence of myocardial infarction (MI) in patients receiving these agents. Whether there is an actual difference in protection from MI remains unresolved, although available data confirm the benefit and safety of ACE inhibitors, in particular perindopril, for myocardial protection.

Role of the renin-angiotensin-aldosterone system and proinflammatory mediators in cardiovascular disease

Inflammation is a key mechanism in the initiation, progression, and clinical sequelae of cardiovascular diseases (CVDs), including atherosclerosis, nephropathy, and cardiomyopathy. Angiotensin II, the major effector peptide of the renin-angiotensin-aldosterone system (RAAS), plays a significant role in the advent and perpetuation of these inflammatory diseases, most notably in atherogenesis. Consequently, suppression of the influence of angiotensin II by angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers may reduce or potentially reverse atherosclerosis and other inflammation-associated CVDs. Angiotensin II receptor blockers and angiotensin-converting enzyme inhibitors exert anti-inflammatory actions and prevent or reduce the development of atherosclerosis in animal models. Clinically, RAAS suppression reduces common carotid and femoral artery intima-media thickness, thus indicating moderation of the vascular disease process. These clinical benefits likely involve restraint of the deleterious effects of angiotensin II in addition to, or independent of, lowering blood pressure. Increasing evidence that the detection and monitoring of vascular inflammation are important tools in the management of atherosclerosis also implicates the RAAS in this pathogenic process. Inflammatory molecules such as intercellular adhesion molecule-1, vascular cell adhesion molecule-1, monocyte chemoattractant protein-1, tumor necrosis factor-alpha, and C-reactive protein have potential diagnostic and prognostic values in CVD and are modified by angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers. Monitoring these markers may be crucial for determining which agents, or combinations of agents, will result in the most clinically beneficial outcomes for patients. Large-scale trials are still required to determine the effects of the long-term suppression of inflammation on CVDs through the use of RAAS modulating agents, as well as to determine how closely markers of inflammatory activity may correlate with CVD outcomes.

The ASCOT trial: clarifying the role of ACE inhibition in the reduction of cardiovascular events in patients with hypertension

Hypertension remains one of the primary causes of preventable death in developed countries. Universally accepted clinical practice guidelines based on well designed trials are needed to ensure standardized treatment for these patients. It has been hypothesized that agents such as calcium channel antagonists and ACE inhibitors may be more effective than beta-adrenoceptor antagonist (beta-blocker)- or diuretic-based regimens. However, until recently, there have been limited data on the efficacy of 'newer' antihypertensive regimens, particularly combination therapy, relative to standard therapeutic options. The ASCOT-BPLA (Anglo-Scandinavian Cardiac Outcomes Trial-Blood Pressure Lowering Arm), a prospective, randomized, controlled trial in >19 250 patients with hypertension, highlights the benefit of a combined amlodipine plus perindopril regimen over an atenolol plus diuretic-based combination in terms of significant reductions (p < 0.05) in all-cause mortality, total cardiovascular events and procedures, and fatal and nonfatal stroke. The ASCOT-BPLA trial underlines the cardiovascular benefit of ACE inhibitors, specifically perindopril, beyond that provided by BP reduction, and potentially reflects a mechanistic feature of the ACE inhibitors. It also suggests that the combination of amlodipine plus perindopril may provide broad-spectrum cardiovascular protection, as well as reduce the incidence of new-onset diabetes mellitus and renal impairment, in addition to its efficacy in lowering BP. The ASCOT-BPLA trial provides evidence of the need to reconsider traditional prescribing recommendations in patients with hypertension, particularly conclusions reached in the US after the publication of the ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial) study. The recently published National Institute for Health and Clinical Excellence (NICE) guidelines in the UK emphasize the efficacy of ACE inhibitors as first-line agents for hypertensive patients <55 years of age and recommend ACE inhibitor therapy at any stage of hypertension management.