Review: Angiotensin-converting enzyme inhibitors and coronary heart disease prevention

DPP3: From biomarker to therapeutic target of cardiovascular diseases

Cardiovascular disease is the leading cause of death globally among non-communicable diseases, which imposes a serious socioeconomic burden on patients and the healthcare system. Therefore, finding new strategies for preventing and treating cardiovascular diseases is of great significance in reducing the number of deaths and disabilities worldwide. Dipeptidyl peptidase 3 (DPP3) is the first zinc-dependent peptidase found among DPPs, mainly distributes within the cytoplasm. With the unique HEXXGH catalytic sequence, it is associated with the degradation of oligopeptides with 4 to 10 amino acids residues. Accumulating evidences have demonstrated that DPP3 plays a significant role in almost all cellular activities and pathophysiological mechanisms. Regarding the role of DPP3 in cardiovascular diseases, it is currently mainly used as a biomarker for poor prognosis in patients with cardiovascular diseases, suggesting that the level of DPP3 concentration in plasma is closely linked to the mortality of diseases such as cardiogenic shock and heart failure. Interestingly, it has been reported recently that DPP3 regulates blood pressure by interacting with the renin-angiotensin system. In addition, DPP3 also participates in the processes of pain signaling, inflammation, and oxidative stress. But the exact mechanism by which DPP3 affects cardiovascular function is not clear. Hence, this review summarizes the recent advances in the structure and catalytic activity of DPP3 and its extensive biological functions, especially its role as a therapeutic target in cardiovascular diseases. It will provide a theoretical basis for exploring the potential value of DPP3 as a therapeutic target for cardiovascular diseases.

CAC score as a possible criterion for administration of angiotensin converting enzyme inhibitors and/or angiotensin receptor blockers: the MultiEthnic Study of Atherosclerosis

INTRODUCTION

Several trials have demonstrated that angiotensin converting enzyme inhibitors (ACEIs) decrease cardiovascular (CV) mortality rates in patients with heart failure; however, the Prevention of Events with Angiotensin-Converting Enzyme Inhibition (PEACE) and European Trial on Reduction of Cardiac Events with Perindopril in Stable Coronary Artery Disease (EUROPA) trials failed to show significant similar preventive effects in normal ejection fraction patients. We evaluated the baseline coronary artery calcium (CAC) score as a predictor of the effects of ACEIs/angiotensin receptor blockers (ARBs) on outcomes among normal ejection fraction participants.

METHODOLOGY

Of 6814 MultiEthnic Study for Atherosclerosis population participants (after exclusion of the patients temporarily using ACEIs and/or ARBs during follow-up), we evaluated 2906 participants who never used ACEIs/ARBs and 368 (8.7%) participants who constantly used them during all baseline and follow-up examinations. In the population studied, 53.9% were men, aged 60.8±10.0 years, who had no apparent clinical CV disease. We compared CV event rates and multivariable-adjusted hazard ratios after stratifying by ACEI/ARB use and stratifying CAC scores by category (0, 1-399, and ≥400).

RESULTS

The event rates varied from 1.8 to 41.2/1000 person years among the CAC groups. Among the participants with a 1-399 CAC score, ACEI/ARB users had significantly lower event rates than nonusers (4.9 vs. 8.2, respectively). Hazard ratio in the adjusted model was 3.1 (95% confidence interval 1.14-8.78, P<0.05). There was no significant event rate difference between ACEI/ARB users and nonusers among other CAC groups.

CONCLUSION

The use of ACEIs/ARBs was associated with significantly fewer CV events in asymptomatic participants with low to intermediate CAC scores. Thus, better risk stratification in asymptomatic individuals (such as using CAC scores) may assist in proper selection of patients for further CV risk reduction strategies.

Novel Therapeutic Role for Dipeptidyl Peptidase III in the Treatment of Hypertension

Dipeptidyl peptidase III (DPP III) cleaves dipeptide residues from the N terminus of polypeptides ranging from 3 to 10 amino acids in length and is implicated in pathophysiological processes through the breakdown of certain oligopeptides or their fragments. In this study, we newly identified the biochemical properties of DPP III for angiotensin II (Ang II), which consists of 8 amino acids. DPP III quickly and effectively digested Ang II with Km = 3.7×10(-6) mol/L. In the in vivo experiments, DPP III remarkably reduced blood pressure in Ang II-infused hypertensive mice without alteration of heart rate. DPP III did not affect hemodynamics in noradrenalin-induced hypertensive mice or normotensive mice, suggesting specificity for Ang II. When DPP III was intravenously injected every other day for 4 weeks after Ang II osmotic minipump implantation in mice, Ang II-induced cardiac fibrosis and hypertrophy were significantly attenuated. This DPP III effect was at least similar to that caused by an angiotensin receptor blocker candesartan. Furthermore, administration of DPP III dramatically reduced the increase in urine albumin excretion and kidney injury and inflammation markers caused by Ang II infusion. Both DPP III and candesartan administration showed slight additive inhibition in the albumin excretion. These results reveal a novel potential use of DPP III in the treatment of hypertension and its protective effects on hypertension-sensitive organs, such as the heart and kidneys.

Cardioprotective role of zofenopril in patients with acute myocardial infarction: a pooled individual data analysis of four randomised, double-blind, controlled, prospective studies

BACKGROUND

Early administration of zofenopril following acute myocardial infarction (AMI) proved to be prognostically beneficial in the four individual randomised, double-blind, parallel-group, prospective SMILE (Survival of Myocardial Infarction Long-term Evaluation) studies. In the present analysis, we evaluated the cumulative efficacy of zofenopril by pooling individual data from the four SMILE studies.

METHODS

3630 patients with AMI were enrolled and treated for 6-48 weeks with zofenopril 30-60 mg/day (n=1808), placebo (n=951), lisinopril 5-10 mg/day (n=520) or ramipril 10 mg/day (n=351). The primary study end point of this pooled analysis was set to 1 year combined occurrence of death or hospitalisation for cardiovascular (CV) causes.

RESULTS

Occurrence of major CV outcomes was significantly reduced with zofenopril versus placebo (-40%; HR=0.60, 95% CI 0.49 to 0.74; p=0.0001) and versus the other ACE inhibitors (-23%; HR=0.77, 0.63 to 0.95; p=0.015). The risk reduction observed under treatment with the other ACE inhibitors was nearly statistically significant (-22%; HR=0.78, 0.60 to 1.02; p=0.072). The benefit of zofenopril versus placebo was already evident after the first 6 weeks of treatment (-28%; HR=0.72, 0.54 to 0.97; p=0.029), while this was not the case for the other ACE inhibitors (-19%; HR=0.81, 0.57 to 1.17; p=0.262). In this early phase of treatment, zofenopril showed a non-significant trend towards a larger reduction in CV events versus the other ACE inhibitors (-11%; HR=0.89, 0.69 to 1.15; p=0.372).

CONCLUSIONS

The pooled data analysis from the SMILE Programme confirms the favourable effects of zofenopril treatment in patients with post-AMI and its long-term benefit in terms of prevention of CV morbidity and mortality.

Effects of early treatment with zofenopril in patients with myocardial infarction and metabolic syndrome: the SMILE Study

Objective

To evaluate the clinical efficacy of the early administration of zofenopril in a group of patients with and without metabolic syndrome (MS+ and MS−) and anterior myocardial infarction enrolled in the Survival of Myocardial Infarction Long-Term Evaluation (SMILE) Study.

Methods

Patients were randomized double-blind to zofenopril (n = 719) or placebo (n = 699) for 6 weeks. The primary end point was the effect of treatment on the 6-week combined occurrence of death and severe congestive heart failure. The secondary end point was the 1-year mortality rate.

Results

Of the 1418 patients included in this post-hoc analysis, 686 (48.3%) had MS. After 6 weeks of treatment zofenopril significantly reduced the incidence of all-cause death and severe congestive failure (risk reduction: 69%, 95% CI: 7–78; 2p = 0.002) in MS+ patients. This was the case for 1-year mortality, too (29%, 95% CI: 4–41; 2p = 0.048). Zofenopril was effective also in MS− patients but the amount of relative risk reduction was less than in MS+ for both the primary (−11%; 2p = 0.61) and secondary endpoint (−19%; 2p = 0.025).

Conclusions

Results of this post-hoc analysis of the SMILE Study demonstrate the striking benefit of early administration of zofenopril in MS+ patients with acute anterior myocardial infarction.

Advances in the management of hyperlipidemia-induced atherosclerosis

Although hyperlipidemia clearly plays a role in developing cardiovascular disease, the 10% of the population with the highest LDL levels account for only 20% of cardiovascular disease events. Thus, in order to significantly reduce the burden of cardiovascular disease, subjects with only modest dyslipidemia need to be treated with lipid-lowering therapy. Current guidelines have recommended aggressive lipid-lowering therapy in subjects at high risk of cardiovascular disease. The rationale behind this and treatment options to achieve target lipid goals are discussed.

LHRH-(1-5): a bioactive peptide regulating reproduction

Luteinizing hormone-releasing hormone-I (LHRH-I) was isolated from the mammalian hypothalamus and shown to be the primary regulator of reproduction through its initiation of pituitary gonadotropin release. Subsequently, it has also been shown to have non-pituitary actions. Although the regulation of LHRH-I synthesis and release has been extensively studied, there is additional evidence to suggest that processing of the peptide represents another layer of regulation. The focus of this review will be on evidence for the action of LHRH-(1-5), the pentapeptide metabolite of LHRH-I, in regulating LHRH-I synthesis, secretion and reproductive behavior. The involvement of LHRH-(1-5) in the control of aspects of reproduction might represent yet another level of regulatory complexity through neuropeptide processing.