PCSK9 inhibition and inflammation: A narrative review

Translocator Protein 18 kDa Tracer 18F-FDPA PET/CTA Imaging for the Evaluation of Inflammation in Vulnerable Plaques

Inflammation induced by activated macrophages within vulnerable atherosclerotic plaques (VAPs) constitutes a significant risk factor for plaque rupture. Translocator protein (TSPO) is highly expressed in activated macrophages. This study investigated the effectiveness of TSPO radiotracers, 18F-FDPA, in detecting VAPs and quantifying plaque inflammation in rabbits. 18 New Zealand rabbits were divided into 3 groups: sham group A, VAP model group B, and evolocumab treatment group C. 18F-FDPA PET/CTA imaging was performed at 12, 16, and 24 weeks in all groups. Optical coherence tomography (OCT) was performed on the abdominal aorta at 24 weeks. The VAP was defined through OCT images, and ex vivo aorta PET imaging was also performed at 24 weeks. The SUVmax and SUVmean of 18F-FDPA were measured on the target organ, and the target-to-background ratio (TBRmax) was calculated as SUVmax/SUVblood pool. The arterial sections of the isolated abdominal aorta were analyzed by HE staining, CD68 and TSPO immunofluorescence staining, and TSPO Western blot. The results showed that at 24 weeks, the plaque TBRmax of 18F-FDPA in group B was significantly higher than in groups A and C. Immunofluorescence staining of CD68 and TSPO, as well as Western blot, confirmed the increased expression of macrophages and TSPO in the corresponding regions of group B. HE staining revealed an increased presence of the lipid core, multiple foam cells, and inflammatory cell infiltration in the area with high 18F-FDPA uptake. This indicates a correlation between 18F-FDPA uptake, inflammation severity, and VAPs. The TSPO-targeted tracer 18F-FDPA shows specific uptake in macrophage-rich regions of atherosclerotic plaques, making it a valuable tool for assessing inflammation in VAPs.

PCSK9 stimulates Syk, PKCδ, and NF-κB, leading to atherosclerosis progression independently of LDL receptor

Proprotein convertase subtilisin/kexin type-9 (PCSK9) binds to and degrades low-density lipoprotein (LDL) receptor, leading to increase of LDL cholesterol in blood. Its blockers have emerged as promising therapeutics for cardiovascular diseases. Here we show that PCSK9 itself directly induces inflammation and aggravates atherosclerosis independently of the LDL receptor. PCSK9 exacerbates atherosclerosis in LDL receptor knockout mice. Adenylyl cyclase-associated protein 1 (CAP1) is the main binding partner of PCSK9 and indispensable for the inflammatory action of PCSK9, including induction of cytokines, Toll like receptor 4, and scavenger receptors, enhancing the uptake of oxidized LDL. We find spleen tyrosine kinase (Syk) and protein kinase C delta (PKCδ) to be the key mediators of inflammation after PCSK9-CAP1 binding. In human peripheral blood mononuclear cells, serum PCSK9 levels are positively correlated with Syk, PKCδ, and p65 phosphorylation. The CAP1-fragment crystallizable region (CAP1-Fc) mitigates PCSK9-mediated inflammatory signal transduction more than the PCSK9 blocking antibody evolocumab does.

Effect of lipid-lowering therapies on C-reactive protein levels: a comprehensive meta-analysis of randomized controlled trials

Chronic low-degree inflammation is a hallmark of atherosclerotic cardiovascular (CV) disease. To assess the effect of lipid-lowering therapies on C-reactive protein (CRP), a biomarker of inflammation, we conducted a meta-analysis according to the PRISMA guidelines. Databases were searched from inception to July 2023. Inclusion criteria were: (i) randomized controlled trials (RCTs) in human, Phase II, III, or IV; (ii) English language; (iii) comparing the effect of lipid-lowering drugs vs. placebo; (iv) reporting the effects on CRP levels; (v) with intervention duration of more than 3 weeks; (vi) and sample size (for both intervention and control group) over than 100 subjects. The between-group (treatment-placebo) CRP absolute mean differences and 95% confidence intervals were calculated for each drug class separately. A total of 171 668 subjects from 53 RCTs were included. CRP levels (mg/L) were significantly decreased by statins [-0.65 (-0.87 to -0.43), bempedoic acid; -0.43 (-0.67 to -0.20), ezetimibe; -0.28 (-0.48 to -0.08)], and omega-3 fatty acids [omega3FAs, -0.27 (-0.52 to -0.01)]. CRP was reduced by -0.40 (-1.17 to 0.38) with fibrates, although not statistically significant. A slight increase of CRP concentration was observed for proprotein convertase subtilisin/kexin type 9 inhibitors [0.11 (0.07-0.14)] and cholesteryl-ester transfer protein inhibitors [0.10 (0.00-0.21)], the latter being not statistically significant. Meta-regression analysis did not show a significant correlation between changes in CRP and LDL cholesterol (LDL-C) or triglycerides. Statins, bempedoic acid, ezetimibe, and omega3FAs significantly reduce serum CRP concentration, independently of LDL-C reductions. The impact of this anti-inflammatory effect in terms of CV prevention needs further investigation.

An update on inclisiran for the treatment of elevated LDL cholesterol

INTRODUCTION

The burden of atherosclerotic cardiovascular disease (ASCVD) persists globally, demanding innovative therapeutic strategies. This manuscript provides an expert opinion on the significance of managing low-density lipoprotein cholesterol in ASCVD prevention and introduces inclisiran, a novel small interfering RNA targeting proprotein convertase subtilisin/kexin type 9 (PCSK9).

AREAS COVERED

This work delves into the intricate mechanism of inclisiran, highlighting its unique approach of hepatic intracellular PCSK9 inhibition, its precision and low off-target effects risk. Pharmacodynamic and pharmacokinetic distinctions from PCSK9 monoclonal antibodies are explored, underlining inclisiran's efficiency, extended duration, and clearance. Clinical trials, including pivotal phase-III placebo-controlled studies (ORION-9, -10, -11), the open-label ORION-3 and pooled safety analysis of these trails including the open-label phase of ORION-8, as well as real-word data are discussed to provide a comprehensive evaluation of inclisiran's efficacy and safety.

EXPERT OPINION

Inclisiran stands as a first-in-class breakthrough in lipid-lowering therapies, showing potential in alleviating the global burden of ASCVD and is supported by multiple global regulatory approvals. To optimize inclisiran's utilization and comprehend its long-term effects, future directions include pediatric studies, cardiovascular outcome trials, and extended-duration investigations. Overall, inclisiran emerges as a precise and effective therapeutic option, offering significant promise for preserving cardiovascular health.

Effects of proprotein convertase subtilisin-kexin type 9 inhibitors on inflammatory and hemostatic parameters in post myocardial infarction patients

Despite progress in treatment, elevated levels of low-density lipoprotein cholesterol (LDL-C) and lipoprotein (a) (Lp(a)), represent a significant part of the residual risk. Both are associated with inflammation and the coagulation fibrinolytic system. The purpose of our research was to evaluate the effect of proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) on lipid parameters and indicators of inflammation, coagulation and fibrinolysis. We included 100 post myocardial infarction (MI) patients with insufficiently controlled LDL-C values despite the maximum dose of statin, and highly elevated Lp(a). Patients received alirocumab or evolocumab (150 mg sc or 140 mg sc every two weeks, respectively), or placebo for 6 months. In patients receiving PCSK9i, a significant decrease in total cholesterol (TC), LDL-C, triglycerides (TG) and Lp(a), and an increase in high density lipoprotein cholesterol (p < 0.001 for all) was found. Before treatment, the concentrations of TC, LDL-C and TG correlated with the concentrations of thrombin activatable fibrinolysis inhibitor (r = 0.41, p < 0.001; r = 0.353, p < 0.001; r = 0.311, p = 0.003, respectively), and plasminogen activator inhibitor-1 (r = 0.302, p = 0.007; r = 0.218, p = 0.049; r = 0.278; p = 0.013, respectively). The concentrations of TC and LDL-C correlated with overall fibrinolytic potential (r = -0.220, p = 0.034; r = -0.207, p = 0.047, respectively). The concentration of TG was related to the concentration of interleukin 6 (r = 0.290, p = 0.004) and interleukin 8 (r = 0.332, p = 0.001). No correlations between Lp(a) and inflammatory or hemostatic variables were found. No associations were found after treatment. Our results show that inflammatory cytokines and fibrinolytic parameters are related to LDL-C and not Lp(a) in post-MI patients before and with neither of them following PCSK9i treatment. The trial registration number: NCT04613167, Date of registration: November 3, 2020.

Neutrophil Percentage-to-Albumin Ratio and Risk of Mortality in Patients on Peritoneal Dialysis

Background

Neutrophil percentage-to-albumin ratio (NPAR), a new inflammatory marker, has been shown to be associated with poor prognosis in patients with cardiovascular disease. However, limited evidence is available for its role in peritoneal dialysis (PD) patients. Our study aimed at investigating the prognostic value of NPAR for mortality in PD patients.

Patients and Methods

This was a single center retrospective cohort study. A total of 1966 PD patients were enrolled in our study from January 2006 to December 2016 and were followed up until December 2021. Patients were stratified into tertiles according to baseline NPAR levels. The associations between NPAR levels with all-cause and cardiovascular mortality were estimated using Cox proportional hazards models. Receiver operating characteristic (ROC) analysis was performed to compare the mortality predictive values of NPAR and other known biomarkers, such as NLR (neutrophil-to-lymphocyte ratio), PLR (platelet-to-lymphocyte ratio), LHR (low-density lipoprotein cholesterol-to-high-density lipoprotein cholesterol ratio) and MLR (monocyte-to-lymphocyte ratio).

Results

During a median follow-up of 48.1 months, 503 (25.6%) patients died, in which cardiovascular disease (CVD) death dominated 50.3%. Multivariate Cox regression analysis revealed that the highest NPAR tertile was significantly associated with a higher risk of all-cause and cardiovascular mortality (HR 1.51, 95% CI 1.14-1.98; HR 1.57, 95% CI 1.07-2.31; respectively) compared with tertile 1. The AUC values of NPAR were 0.62 (95% CI 0.60-0.65, P < 0.001) for all-cause mortality and 0.61 (95% CI 0.57-0.65, P < 0.001) for cardiovascular mortality.

Conclusion

Our study showed that higher NPAR levels were independently associated with increased risk of all-cause and cardiovascular mortality in PD patients. Notably, our results demonstrated that NPAR exhibited superior predictive value for mortality compared to NLR, PLR, MLR, and LHR.

Sex X Time Interactions in Lp(a) and LDL-C Response to Evolocumab

The aim of this study was to evaluate whether there were significant sex x time interactions in lipoprotein(a) (Lp(a)) and low-density lipoprotein cholesterol (LDL-C) response to treatment with the Proprotein Convertase Subtilisin/Kexin type 9 inhibitor (PCSK9i) Evolocumab, in a real-life clinical setting. For this purpose, we pooled data from 176 outpatients (Men: 93; Women: 83) clinically evaluated at baseline and every six months after starting Evolocumab. Individuals who had been on PCSK9i for less than 30 months and nonadherent patients were excluded from the analysis. Over time, absolute values of Lp(a) plasma concentrations significantly decreased in the entire cohort (p-value < 0.001) and by sex (p-value < 0.001 in men and p-value = 0.002 in and women). However, there were no sex-related significant differences. Absolute plasma concentrations of LDL-C significantly decreased over time in the entire cohort and by sex (p-value < 0.001 always), with greater improvements in men compared to women. The sex x time interaction was statistically significant in LDL-C (all p-values < 0.05), while absolute changes in Lp(a) were not influenced by either sex or time (all p-value > 0.05). Our data partially reinforce the presence of differences in response to treatment to PCSK9i between men and women and are essential to gain a better understanding of the relationship between LDL-C and Lp(a) lowering in response to PCSK9i. Further research will clarify whether these sex-related significant differences translate into a meaningful difference in the long-term risk of ASCVD.

PCSK9 activation promotes early atherosclerosis in a vascular microphysiological system

Atherosclerosis is a primary precursor of cardiovascular disease (CVD), the leading cause of death worldwide. While proprotein convertase subtilisin/kexin 9 (PCSK9) contributes to CVD by degrading low-density lipoprotein receptors (LDLR) and altering lipid metabolism, PCSK9 also influences vascular inflammation, further promoting atherosclerosis. Here, we utilized a vascular microphysiological system to test the effect of PCSK9 activation or repression on the initiation of atherosclerosis and to screen the efficacy of a small molecule PCSK9 inhibitor. We have generated PCSK9 over-expressed (P+) or repressed (P-) human induced pluripotent stem cells (iPSCs) and further differentiated them to smooth muscle cells (viSMCs) or endothelial cells (viECs). Tissue-engineered blood vessels (TEBVs) made from P+ viSMCs and viECs resulted in increased monocyte adhesion compared to the wild type (WT) or P- equivalents when treated with enzyme-modified LDL (eLDL) and TNF-α. We also found significant viEC dysfunction, such as increased secretion of VCAM-1, TNF-α, and IL-6, in P+ viECs treated with eLDL and TNF-α. A small molecule compound, NYX-1492, that was originally designed to block PCSK9 binding with the LDLR was tested in TEBVs to determine its effect on lowering PCSK9-induced inflammation. The compound reduced monocyte adhesion in P+ TEBVs with evidence of lowering secretion of VCAM-1 and TNF-α. These results suggest that PCSK9 inhibition may decrease vascular inflammation in addition to lowering plasma LDL levels, enhancing its anti-atherosclerotic effects, particularly in patients with elevated chronic inflammation.

Current Medical Therapy and Revascularization in Peripheral Artery Disease of the Lower Limbs: Impacts on Subclinical Chronic Inflammation

Peripheral artery disease (PAD), coronary artery disease (CAD), and cerebrovascular disease (CeVD) are characterized by atherosclerosis and inflammation as their underlying mechanisms. This paper aims to conduct a literature review on pharmacotherapy for PAD, specifically focusing on how different drug classes target pro-inflammatory pathways. The goal is to enhance the choice of therapeutic plans by considering their impact on the chronic subclinical inflammation that is associated with PAD development and progression. We conducted a comprehensive review of currently published original articles, narratives, systematic reviews, and meta-analyses. The aim was to explore the relationship between PAD and inflammation and evaluate the influence of current pharmacological and nonpharmacological interventions on the underlying chronic subclinical inflammation. Our findings indicate that the existing treatments have added anti-inflammatory properties that can potentially delay or prevent PAD progression and improve outcomes, independent of their effects on traditional risk factors. Although inflammation-targeted therapy in PAD shows promising potential, its benefits have not been definitively proven yet. However, it is crucial not to overlook the pleiotropic properties of the currently available treatments, as they may provide valuable insights for therapeutic strategies. Further studies focusing on the anti-inflammatory and immunomodulatory effects of these treatments could enhance our understanding of the mechanisms contributing to the residual risk in PAD and pave the way for the development of novel therapies.

Bempedoic Acid can Reduce Cardiovascular Events in Combination with Statins or As Monotherapy: A Systematic Review and Meta-analysis

AIM

Bempedoic acid has shown noteworthy progress in the prevention and management of atherosclerotic cardiovascular disease (ASCVD) in recent years. However, there has been a lack of high-quality evidence regarding the risk reduction of clinical events with bempedoic acid. Therefore, the aim of this article is to conduct a comprehensive evaluation of the impact of bempedoic acid on the incidence of cardiovascular events.

METHODS

A systematic review and meta-analysis of randomized controlled trials pertaining to bempedoic acid was carried out. We conducted a systematic search across the Pubmed, Embase, and Cochrane Central Register of Controlled Trials databases to identify relevant studies published from inception to 23 April 2023. A total of four trials comparing the clinical benefit achieved with bempedoic acid versus placebo were included.

RESULTS

Our analysis comprised four trials that encompassed a total of 17,323 patients. In comparison to the placebo, bempedoic acid showed a significant reduction in the risk of major adverse cardiovascular events (MACE) [relative risk (RR), 0.86, 95% confidence interval (CI) 0.87-0.94]. Additionally, bempedoic acid substantially lowered the occurrence of fatal or nonfatal myocardial infarction (RR 0.76, 95% CI 0.66-0.89), hospitalization for unstable angina (RR 0.70, 95% CI 0.55-0.89), and coronary revascularization (RR 0.82, 95% CI 0.73-0.92). There was also a similar reduction in MACE in patients on the maximally tolerated statin therapy.

CONCLUSION

Bempedoic acid may reduce the risk of cardiovascular events regardless of whether the patient is taking stains or not.

REGISTRATION

PROSPERO registration number CRD42023422932.

Effect of PCSK9 Monoclonal Antibody Versus Placebo/Ezetimibe on Atrial Fibrillation in Patients at High Cardiovascular Risk: A Meta-Analysis of 26 Randomized Controlled Trials

BACKGROUND

Patients at high cardiovascular risk are closely associated with an increased risk of atrial fibrillation (AF). Whether proprotein convertase subtilisin/kexin type 9 monoclonal antibodies (PCSK9 mAbs) can attenuate AF progression remains unknown.

METHODS

To compare PCSK9 mAbs with placebo or ezetimibe to explore the effect of PCSK9 mAbs therapy on the end-point of incidence of AF, we searched PubMed, Embase, and ClinicalTrials.gov for articles. We used Mantel-Haenszel risk ratio (RR) with corresponding 95% CI for the categorical data, including the incidence of AF and predefined other outcomes of interest.

RESULTS

We included 21 articles consisting of 26 randomized controlled trials with a total of 95,635 participants. Quantitative synthesis revealed that PCSK9 mAbs significantly reduce the incidence of AF events (RR 0.84; 95% CI 0.72-0.98; p = 0.03), whereas no obvious differences were seen between the PCSK9 mAbs group and the ezetimibe group (RR 0.90; 95% CI 0.29-2.76; p = 0.85). PCSK9 mAbs also markedly decreased the incidence of cerebrovascular events (RR 0.75; 95% CI 0.66-0.85; p < 0.0001) and new-onset hypertension (RR 0.92; 95% CI 0.87-0.97; p = 0.003), but not the risk of cardiovascular death (RR 0.95; 95% CI 0.85-1.07; p = 0.40) and new-onset diabetes mellitus (RR 1.01; 95% CI 0.95-1.08; p = 0.67).

CONCLUSIONS

Overall, the PCSK9 mAbs therapy reduced AF and presented certain cardiovascular benefits in patients at high cardiovascular risk. Further big-scale and long follow-up duration randomized controlled trials that compare PCSK9 mAbs with ezetimibe are required to evaluate the effect of PCSK9 mAbs versus ezetimibe on AF.

Effects of PCSK9 inhibitors on coronary microcirculation, inflammation and cardiac function in patients with CHD after PCI: a protocol for systematic review and meta-analysis

INTRODUCTION

Coronary heart disease (CHD) is one of the common cardiovascular diseases that seriously jeopardise human health, and endothelial inflammation and dyslipidaemia are the initiating links leading to its occurrence. Percutaneous coronary intervention (PCI) is one of the most effective surgical treatments for CHD with narrowed or blocked blood vessels, which can quickly unblock the blocked vessels and restore coronary blood supply. However, most patients may experience coronary microcirculation disorders (CMDs) and decreased cardiac function after PCI treatment, which directly affects the efficacy of PCI and the prognosis of patients. Preprotein converting enzyme subtilisin/Kexin 9 (PCSK9) inhibitors are novel pleiotropy lipid-lowering drug with dual anti-inflammation and lipid-lowering effects, and represent a new clinical pathway for rapid correction of dyslipidaemia. Therefore, we designed this protocol to systematically evaluate the effects of PCSK9 inhibitors on coronary microcirculation and cardiac function in patients with CHD after PCI, and to provide high-quality evidence-based evidence for the clinical application of PCSK9 inhibitors.

METHODS AND ANALYSIS

This protocol is reported strictly in accordance with the 2020 Preferred Reporting Items for Systematic Reviews and Meta-analyses Protocols Guidelines. We will search PubMed, EMBASE, Web of Science and three Chinese databases (CNKI, Wanfang and VIP database) according to preset search strategies, without language and publication data restrictions. We will work with manual retrieval to screen references that have been included in the literature. Google Scholar will be used to search for grey literature. The final included literature must meet the established inclusion criteria. Titles, abstracts and full text will be extracted independently by two reviewers, and disagreements will be resolved through discussion or the involvement of a third reviewer. Extracted data will be analysed using Review Manager V.5.3. The Cochrane Risk of Bias Tool will be used to evaluate the risk of bias. Publication bias will be assessed by funnel plots. Heterogeneity will be assessed by I2 test and subgroup analyses will be used to further investigate potential sources of heterogeneity. The quality of the literature will be assessed by GRADE score. This protocol will start in January 2026 and end in December 2030.

ETHICS AND DISSEMINATION

This study is a systematic review of published literature data and no special ethical approval was required.

PROSPERO REGISTRATION NUMBER

CRD42022346189.

The Inhibition of Evolocumab on Non-Infarct-Related Artery Disease in Patients with ST-Elevation Myocardial Infarction

Purpose

The effects of combing evolocumab and statin on the clinical outcome and physiological function of coronary arteries in STEMI patients with non-infarct-related artery (NIRA) disease are still unclear.

Methods

A total of 355 STEMI patients with NIRA were enrolled in this study, who underwent combined quantitative flow ratio (QFR) at baseline and after 12 months of treatment with statin monotherapy or statin plus evolocumab.

Results

Diameter stenosis and lesion length were significantly lower in the group undergoing statin plus evolocumab. While the group exhibited significantly higher minimum lumen diameter (MLD), and QFR values. Statin plus evolocumab (OR = 0.350; 95% CI: 0.149-0.824; P = 0.016) and plaque lesion length (OR = 1.223; 95% CI: 1.102-1.457; P = 0.033) were independently associated with rehospitalization for unstable angina (UA) within 12 months.

Conclusion

Evolocumab combined with statin therapy can significantly improve the anatomical and physiological function of the coronary arteries and downregulate the re-hospitalization rate due to UA in STEMI patients with NIRA.

Emerging Therapies for the Treatment of Atherosclerotic Cardiovascular Disease: From Bench to Bedside

Primarily a consequence of sedentary lifestyle, atherosclerosis has already reached pandemic proportions, and with every year the burden of it is only increasing. As low-density lipoprotein cholesterol (LDL-C) represents a crucial factor in atherosclerosis formation and progression, stringent lipid-lowering therapy could conceivably be the key to preventing the unfavorable outcomes that arise as a consequence of atherosclerosis. The use of statins in lipid-lowering is often burdened by adverse events or is insufficient to prevent cardiovascular events as a monotherapy. Therefore, in the present review, the authors aimed to discuss the underlying mechanisms of dyslipidemia and associated atherosclerotic cardiovascular disease (ASCVD) and preclinical and clinical trials of novel therapeutic approaches to its treatment, some of which are still in the early stages of development. Apart from novel therapies, a novel change in perspective is needed. Specifically, the critical objective in the future management of ASCVD is to embrace emerging evidence in the field of atherosclerosis, because clinicians are often burden by common practice and personal experience, both of which have so far been shown to be futile in the setting of atherosclerosis.

Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitors and the Risk of Fracture: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Osteoporosis and hyperlipidemia are closely correlated and statins might be associated with a decreased risk of fracture. We aimed to investigate the association between proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) therapy and the risk of fracture. The PubMed, Cochrane library, and EMBASE databases were systematically searched from the inception dates to October 22, 2022. Randomized clinical trials (RCTs) that addressed to fracture events of participants using alirocumab, evolocumab, bococizumab or inclisiran, with a follow-up of ≥ 24 weeks were included. Meta-analyses were conducted to calculate the odds ratio (OR) with 95% confidence intervals (CIs) for major osteoporotic fracture, hip fracture, osteoporotic non-vertebral fracture, and total fracture. 30 trials assessing PCSK9i among 95, 911 adults were included. There were no significant associations between PCSK9i therapy and the risk of major osteoporotic fracture [OR 1.08 (95% Cl 0.87-1.34), p = 0.49], hip fracture [OR 1.05 (95% Cl 0.73-1.53), p = 0.79], osteoporotic non-vertebral fracture [OR 1.03 (95% Cl 0.80-1.32), p = 0.83], and total fracture [OR 1.03 (95% Cl 0.88-1.19), p = 0.74] over a period of 6-64 months. No significant associations were detected in any of the sensitivity analyses and subgroup analyses stratified by the type of PCSK9i, follow-up duration, age, sex, sample size, and patient profile. Pooled results of our meta-analysis showed that exposure to PCSK9i was not associated with reduced risks of fracture in the short term.

Evaluation of subclinical atherosclerosis in rosacea patients by flow-mediated dilatation method

BACKGROUND

Rosacea may contribute to the development of cardiovascular (CV) diseases by causing endothelial dysfunction (ED), which is known to be the initial step of atherosclerosis, due to its inflammatory features.

OBJECTIVE

This study aimed to assess ED in rosacea patients using the flow-mediated dilatation (=dilation) (FMD) method.

METHODS

Seventy-three rosacea patients and 73 age, gender-matched healthy volunteers were enrolled. Individuals with cardiac risk factors, pregnant, and lactating women were excluded. Demographic, clinical data and anthropometric measurements were recorded. FMD measurement was performed ultrasonographically by a cardiologist. Systolic and diastolic blood pressures (BP) were measured and hemogram, erythrocyte sedimentation rate (ESR), C-Reactive Protein (CRP), total cholesterol, triglyceride, low-density lipoprotein (LDL), high-density lipoprotein (HDL), neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), mean platelet volume (MPV), and fasting blood glucose values were assessed.

RESULTS

The FMD value was statistically lower in rosacea patients compared with healthy controls (p = 0.000). Metabolic syndrome, systolic and diastolic BPs, and plasma NLR were higher in the rosacea group (p = 0.009, p = 0.000, p = 0.000, p = 0.000, respectively). According to the multivariate linear regression analysis, rosacea type significantly predicted FMD.

CONCLUSIONS

Rosacea is not only a disease limited to the skin, but it may also have systemic involvement. A significant difference was found between FMD values measured in between the case and control groups, suggesting rosacea may have an atherogenic effect. Possible cardiac risks should be considered in rosacea patients, and further evaluation could be warranted.

Role of Lipoprotein Levels and Function in Atherosclerosis Associated with Autoimmune Rheumatic Diseases

Immune and inflammatory mediators in autoimmune rheumatic diseases induce modification in the activity of enzymes pivotal for lipid metabolism and promote a proatherogenic serum lipid profile. However, disturbances in low- and high-density lipoprotein composition and increased lipid oxidation also occur. Therefore, lipoprotein dysfunction causes intracellular cholesterol accumulation in macrophages, smooth muscle cells, and platelets. Overall, both plaque progression and acute cardiovascular events are promoted. Single rheumatic diseases may present a particular pattern of lipid disturbances so that standard methods to evaluate cardiovascular risk may not be accurate enough. In general, antirheumatic drugs positively affect lipid metabolism in these patients.

Monoclonal Antibodies, Gene Silencing and Gene Editing (CRISPR) Therapies for the Treatment of Hyperlipidemia-The Future Is Here

Hyperlipidemia is a significant risk factor for atherosclerotic cardiovascular disease. Undertreatment of elevated lipids persists despite existing therapies. Here, we provide an update on monoclonal antibodies, gene silencing therapies, and gene editing techniques for the management of hyperlipidemia. The current era of cutting-edge pharmaceuticals targeting low density lipoprotein cholesterol, PCSK9, lipoprotein (a), angiopoietin-like 3, and apolipoprotein C3 are reviewed. We outline what is known, studies in progress, and futuristic goals. This review of available and upcoming biotechnological lipid therapies is presented for clinicians managing patients with familial hyperlipidemia, statin intolerance, hypertriglyceridemia, or elevated lipoprotein (a) levels.

Monomeric C-Reactive Protein in Atherosclerotic Cardiovascular Disease: Advances and Perspectives

This review aimed to trace the inflammatory pathway from the NLRP3 inflammasome to monomeric C-reactive protein (mCRP) in atherosclerotic cardiovascular disease. CRP is the final product of the interleukin (IL)-1β/IL-6/CRP axis. Its monomeric form can be produced at sites of local inflammation through the dissociation of pentameric CRP and, to some extent, local synthesis. mCRP has a distinct proinflammatory profile. In vitro and animal-model studies have suggested a role for mCRP in: platelet activation, adhesion, and aggregation; endothelial activation; leukocyte recruitment and polarization; foam-cell formation; and neovascularization. mCRP has been shown to deposit in atherosclerotic plaques and damaged tissues. In recent years, the first published papers have reported the development and application of mCRP assays. Principally, these studies demonstrated the feasibility of measuring mCRP levels. With recent advances in detection techniques and the introduction of first assays, mCRP-level measurement should become more accessible and widely used. To date, anti-inflammatory therapy in atherosclerosis has targeted the NLRP3 inflammasome and upstream links of the IL-1β/IL-6/CRP axis. Large clinical trials have provided sufficient evidence to support this strategy. However, few compounds target CRP. Studies on these agents are limited to animal models or small clinical trials.

PCSK9 inhibitors for acute coronary syndrome: the era of early implementation

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, a new cholesterol-lowering strategy, can decrease low-density lipoprotein cholesterol (LDL-C) levels by inhibiting PCSK9 and reducing the degradation of LDL receptors; thus, they are impacting the management of dyslipidemia to the prevention of cardiovascular events. Recent guidelines recommend PCSK9 inhibitors for patients who fail to achieve target lipids after ezetimibe/statin therapy. As PCSK9 inhibitors have been demonstrated to significantly and safely reduce LDL-C, discussions have begun to explore its optimal timing in coronary artery disease, especially in subjects with acute coronary syndrome (ACS). Also, their additional benefits, such as anti-inflammatory effects, plaque regression effects, and cardiovascular event prevention, have become the focus of recent research. Several studies, including EPIC-STEMI, suggest the lipid-lowering effects of early PCSK9 inhibitors in ACS patients, while some studies such as PACMAN-AMI suggest that early PCSK9 inhibitors can decelerate plaque progression and reduce short-term risks of cardiovascular events. Thus, PCSK9 inhibitors are entering the era of early implementation. In this review, we are committed to summarizing the multidimensional benefits of early implementation of PCSK9 inhibitors in ACS.

Bempedoic acid and its role in contemporary management of hyperlipidemia in atherosclerosis

Atherosclerotic heart disease is the leading cause of mortality and morbidity in the USA. Low density lipoprotein (LDL) has been the target for many hypolipidemic agents to modify atherosclerotic risk. Bempedoic acid is a novel hypolipidemic drug that inhibits the enzymatic activity of ATP citrate lyase in the cholesterol synthesis pathway. CLEAR Harmony, CLEAR Wisdom, CLEAR Tranquillity and CLEAR Serenity have shown safety and efficacy associated with long term administration of this drug. Studies have shown effectiveness in reducing LDL-C in both statin intolerant patients and in patients on maximally tolerated doses of statin. The fixed drug combination of bempedoic acid and ezetimibe in a recent phase III showed significant reduction in LDL compared with placebo, which might be a promising future for LDL reduction among statin intolerant patients. Bempedoic acid also reduced inflammatory markers like hs-CRP. Given these results, bempedoic acid alone and in combination with ezetimibe received the USA FDA approval for adults with heterozygous familial hypercholesterolaemia or established atherosclerotic cardiovascular disease. We present a comprehensive review exploring the underlying mechanism, pre-clinical studies, and clinical trials of bempedoic acid and discuss the potential future role of the drug in treating hyperlipidaemia.

PCSK9 inhibitors for anti-inflammation in atherosclerosis: protocol for a systematic review and meta-analysis of randomised controlled trials

INTRODUCTION

Atherosclerosis is the leading cause of cardiovascular disease (CVD), which is one of the most common causes of morbidity and mortality worldwide. Lipid accumulation and inflammation play a crucial role in the pathogenesis of atherosclerosis. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are an emerging lipid-lowering agent reported as a potential anti-inflammation effect in the prevention of CVD. However, the anti-inflammatory effect is still elusive. Therefore, a systematic review and meta-analysis is needed to analyse the anti-inflammatory effect of PCSK9 inhibitors on atherosclerosis in practice.

METHODS AND ANALYSIS

This protocol was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols. We will include double-blind, randomised controlled trials that reported changes in the levels of inflammatory markers, with an intervention arm of PCSK9 inhibitors and a treatment duration of more than 2 weeks. The following databases will be mainly searched from 1 January 2003 to the formal search date: PubMed, Embase, Web of Science and the Cochrane Central Register of Controlled Trials. The primary aim is to assess the effect of PCSK9 inhibitors on inflammatory markers, including circulating inflammatory markers such as C-reactive protein, high-sensitivity C-reactive protein, white cell counts, IL-1β, IL-6 and TNF-α and local inflammatory markers such as the most diseased segment target-to-background ratio of the index vessel in adult patients with atherosclerosis. We will assess the quality of evidence, heterogeneity and report bias following the recommendations of the Cochrane Handbook for Systematic Reviews of Interventions.

ETHICS AND DISSEMINATION

Due to the systematic review being based on published studies, no ethics approval is required. The study results will be presented at international conferences and published in a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42022297710.

Pharmacological rationale for the very early treatment of acute coronary syndrome with monoclonal antibodies anti-PCSK9

Immediate and aggressive lipid lowering therapies after acute coronary syndromes (ACS) and percutaneous coronary interventions (PCI) are supported by the ESC/EAS dyslipidemia guidelines, recommending the initiation of high-intensity statin therapy within the first 1-4 days of hospitalization. However, whether non statin lipid-lowering agents, added to statin treatment, could produce a further reduction in the risk of major adverse cardiovascular events (MACE) is still unknown. Thus, the efficacy of early treatment post-ACS with monoclonal antibodies (mAbs) anti PCSK9, evolocumab and alirocumab, is under investigation. The rationale to explore the rapid and aggressive pharmacological intervention with PCSK9 mAbs is supported by at least five confirmatory data in ACS: 1) circulating PCSK9 levels are raised during ACS 2) PCSK9 may stimulate platelet reactivity, this last being pivotal in the recurrence of ischemic events; 3) PCSK9 is associated with intraplaque inflammation, macrophage activation and endothelial dysfunction; 4) PCSK9 concentrations are associated with inflammation in the acute phase of ACS; and 5) statins raise PCSK9 levels promptly and, at times, dramatically. In this scenario, appropriate pharmacodynamic characteristics of anti PCSK9 therapies are a prerequisite for an effective response. Monoclonal antibodies act on circulating PCSK9 with a direct and rapid binding by blocking the interaction with the low-density lipoprotein receptor (LDLR). Evolocumab and alirocumab show a very rapid (within 4 h) and effective suppression of circulating unbound PCSK9 (- 95 % ÷ - 97 %). This inhibition results in a significant reduction of LDL-cholesterol (LDL-C) after 48 h (- 35 %) post injection with a full effect after 7-10 days (55-75 %). The complete and swift inhibitory action by evolocumab and alirocumab could have a potential clinical impact in ACS patients, also considering their potential inhibition of PCSK9 within the atherosclerotic plaque. Thus, administration of evolocumab or alirocumab is effective in lowering LDL-C levels in ACS, although the efficacy to prevent further cardiovascular (CV) events is still undetermined. The answer to this question will be provided by the ongoing clinical trials with evolocumab and alirocumab in ACS. In the present review we will discuss the pharmacological and biological rationale supporting the potential use of PCSK9 mAbs in ACS patients and the emerging evidence of evolocumab and alirocumab treatment in this clinical setting.

Effect of empagliflozin on plasma proprotein convertase subtilisin/kexin type 9 (PCSK9) in patients with type 2 diabetes

AIM

Cardiovascular benefits of sodium-glucose cotrasporter-2 (SGLT2) inhibitors occur despite a modest increase in low-density lipoprotein cholesterol (LDL-c). We tested whether the effects of chronic SGLT2 inhibition on lipid profile composition are mediated by elevation in plasma proprotein convertase subtilisin/kexin type 9 (PCSK9) levels inhibiting LDL clearance.

METHODS

78 patients with type 2 diabetes (T2D) received empagliflozin 25 mg/d in an open-label design. At enrollment and after 4-week therapy, fasting blood samples were collected for the measurement of plasma PCSK9, glucose, total and fractional cholesterol, and triglycerides.

RESULTS

Plasma PCSK9 was not significantly affected by empagliflozin (-10.7 [-24.1, 2.7] ng/mL). The treatment induced a mild increase in high-density lipoprotein cholesterol (+1.7 [0.5, 3.0] mg/dL), without significant LDL-c alterations (+1.0 [-4.1, 6.0] mg/dl). Changes in LDL-c were associated with changes in fasting glucose levels (β = 0.320, p = 0.017), but not with plasma PCSK9 (β = 0.010, p = 0.800), after adjustment for age, sex, baseline LDL-c, and body weight change.

CONCLUSION

In patients with T2D, chronic SGLT2 inhibition with empagliflozin has no potentially harmful effects on circulating PCSK9 levels. This finding does not support a pathogenetic role of plasma PCSK9 in the mild plasma lipid alterations observed during SGLT2i treatment.

Targeting PCSK9 Ameliorates Graft Vascular Disease in Mice by Inhibiting NLRP3 Inflammasome Activation in Vascular Smooth Muscle Cells

Background

Graft vascular disease (GVD), which limits the long-term survival of patients after solid-organ transplantation, is associated with both immune responses and nonimmune factors, including dyslipidemia. Recent studies have shown that inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9), a U.S. Federal Drug Administration-approved treatment for hyperlipidemia, reduces cardiovascular events, regulates inflammatory responses, and enhances the efficacy of immune checkpoint therapy in cancer treatment through a cholesterol-independent mechanism. However, whether targeting PCSK9 is a potential therapeutic strategy for GVD remains unknown.

Methods

Serum samples and grafts were harvested from male mice undergoing abdominal aortic transplantation. The pathological alterations in the aortic grafts were detected by hematoxylin and eosin staining, Verhoeff’s Van Gieson staining, and Masson staining. Inflammatory cell infiltration and proinflammatory cytokine expression in the aortic grafts were detected by immunohistochemistry and quantitative real-time polymerase chain reaction (qRT-PCR), respectively. The regulatory effects of PCSK9 on vascular smooth muscle cell (VSMC) migration and proliferation were examined by transwell, EdU, and western blot assays. The effect of Evolocumab, a PCSK9 inhibitor, on GVD in humanized PCSK9 mice was also evaluated.

Results

PCSK9 was upregulated in the serum, grafts, and liver of mice in the allograft group subjected to abdominal aortic transplantation. Pcsk9 knockout significantly reduced vascular stenosis, the intimal hyperplasia area and collagen deposition. Pcsk9 depletion also inhibited macrophage recruitment and the mRNA expression of proinflammatory cytokines in aortic grafts. Furthermore, Pcsk9 knockout suppressed the migration and proliferation of VSMCs, which was related to the inhibition of NLRP3 inflammasome activation. Meanwhile, Evolocumab significantly ameliorated GVD in humanized PCSK9 mice.

Conclusion

PCSK9 is upregulated in a mouse model of GVD, and Pcsk9 knockout reduces vascular occlusion, suggesting that PCSK9 may be a promising target for the treatment of GVD.

Biological Actions, Implications, and Cautions of Statins Therapy in COVID-19

The Coronavirus Disease 2019 (COVID-19) showed worse prognosis and higher mortality in individuals with obesity. Dyslipidemia is a major link between obesity and COVID-19 severity. Statins as the most common lipid regulating drugs have shown favorable effects in various pathophysiological states. Importantly, accumulating observational studies have suggested that statin use is associated with reduced risk of progressing to severe illness and in-hospital death in COVID-19 patients. Possible explanations underlie these protective impacts include their abilities of reducing cholesterol, suppressing viral entry and replication, anti-inflammation and immunomodulatory effects, as well as anti-thrombosis and anti-oxidative properties. Despite these benefits, statin therapies have side effects that should be considered, such as elevated creatinine kinase, liver enzyme and serum glucose levels, which are already elevated in severe COVID-19. Concerns are also raised whether statins interfere with the efficacy of COVID-19 vaccines. Randomized controlled trials are being conducted worldwide to confirm the values of statin use for COVID-19 treatment. Generally, the results suggest no necessity to discontinue statin use, and no evidence suggesting interference between statins and COVID-19 vaccines. However, concomitant administration of statins and COVID-19 antiviral drug Paxlovid may increase statin exposure and the risk of adverse effects, because most statins are metabolized mainly through CYP3A4 which is potently inhibited by ritonavir, a major component of Paxlovid. Therefore, more clinical/preclinical studies are still warranted to understand the benefits, harms and mechanisms of statin use in the context of COVID-19.

SORBS2 as a molecular target for atherosclerosis in patients with familial hypercholesterolemia

Background

Familial hypercholesterolemia (FH) is a metabolic disease in which patients are prone to develop premature atherosclerosis (AS). Sorbin and SH3 Domain Containing 2 (SORBS2) is known to play a role in coronary heart disease (CHD). However, the mechanism underlying SORBS2 involvement in the development of hypercholesterolemia remains unknown. Here, we investigated the effects of SORBS2 on inflammation and foam cell formation and its underlying mechanisms.

Methods

Using Bioinformatics analysis, we established that SORBS2 is upregulated in patients with FH. Circulating concentrations of SORBS2 were measured using ELISA kit (n = 30). The association between circulating SORBS2 levels and inflammatory factors or lipid indexes were conducted using Spearman correlation analysis. We further conducted in vitro experiments that the expression of SORBS2 were analyzed, and SORBS2 siRNA were transfected into oxidized LDL (OxLDL)-induced macrophages, followed by western blot and immunofluorescence.

Results

Circulating SORBS2 levels were positively associated with inflammatory factors and lipid indexes. We also observed that high in vitro expression of SORBS2 in OxLDL-induced macrophages. After SORBS2 silencing, Nod like receptor family pyrin domain-containing 3 protein(NLRP3)-Caspase1 activation and NF-κB activation were attenuated, and secretion of pro-inflammatory cytokines (IL-1β and IL-18) was decreased. Moreover, SORBS2 silencing blocked reactive oxygen species (ROS) production and lipid accumulation, and promoted cholesterol efflux through ABCG1-PPARγ pathway.

Conclusions

SORBS2 regulates lipid-induced inflammation and foam cell formation, and is a potential therapeutic target for hypercholesterolemia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03381-z.

The Importance of Arterial Stiffness Assessment in Patients with Familial Hypercholesterolemia

Cardiovascular diseases are still the leading cause of mortality due to increased atherosclerosis worldwide. In the background of accelerated atherosclerosis, the most important risk factors include hypertension, age, male gender, hereditary predisposition, diabetes, obesity, smoking and lipid metabolism disorder. Arterial stiffness is a firmly established, independent predictor of cardiovascular risk. Patients with familial hypercholesterolemia are at very high cardiovascular risk. Non-invasive measurement of arterial stiffness is suitable for screening vascular dysfunction at subclinical stage in this severe inherited disorder. Some former studies found stiffer arteries in patients with familial hypercholesterolemia compared to healthy controls, while statin treatment has a beneficial effect on it. If conventional drug therapy fails in patients with severe familial hypercholesterolemia, PCSK9 inhibitor therapy should be administered; if these agents are not available, performing selective LDL apheresis could be considered. The impact of recent therapeutic approaches on vascular stiffness is not widely studied yet, even though the degree of accelerated athero and arteriosclerosis correlates with cardiovascular risk. The authors provide an overview of the diagnosis of familial hypercholesterolemia and the findings of studies on arterial dysfunction in patients with familial hypercholesterolemia, in addition to presenting the latest therapeutic options and their effects on arterial elasticity parameters.

New Treatment Targets and Innovative Lipid-Lowering Therapies in Very-High-Risk Patients with Cardiovascular Disease

The effective and fast reduction of circulating low-density lipoprotein cholesterol (LDL-C) is a cornerstone for secondary prevention of atherosclerotic disease progression. Despite the substantial lipid-lowering effects of the established treatment option with statins and ezetimibe, a significant proportion of very-high-risk patients with cardiovascular disease do not reach the recommended treatment goal of <55 mg/dL (<1.4 mmol/L). Novel lipid-lowering agents, including the proprotein convertase subtilisin/kexin type 9 (PCSK9) antibodies alirocumab and evolocumab, the small interfering ribonucleotide acid (si-RNA) inclisiran, as well as the recently approved bempedoic acid, now complete the current arsenal of LDL-C lowering agents. These innovative therapies have demonstrated promising results in clinical studies. Besides a strong reduction of LDL-C by use of highly effective agents, there is still discussion as to whether a very rapid achievement of the treatment goal should be a new strategic approach in lipid-lowering therapy. In this review, we summarize evidence for the lipid-modifying properties of these novel agents and their safety profiles, and discuss their potential pleiotropic effects beyond LDL-C reduction (if any) as well as their effects on clinical endpoints as cardiovascular mortality. In addition to a treatment strategy of “the lower, the better”, we also discuss the concept of “the earlier, the better”, which may also add to the early clinical benefit of large LDL-C reduction after an acute ischemic event.

PCSK9 Plasma Levels Are Associated with Mechanical Vascular Impairment in Familial Hypercholesterolemia Subjects without a History of Atherosclerotic Cardiovascular Disease: Results of Six-Month Add-On PCSK9 Inhibitor Therapy

Proprotein convertase subtilisin/kexin type-9 (PCSK9) is a key regulator of low-density lipoprotein (LDL) metabolism involved in the degradation of the low-density lipoprotein receptor (LDLR) through complex mechanisms. The PCSK9 plasma levels change according to lipid lowering therapy (LLT). Few data exist regarding the role of PCSK9 in vascular damage. We aimed to evaluate the impact of PCSK9 plasma levels on pulse wave velocity (PWV) and the effect of PCSK9 inhibitors (PCSK9-i) on circulating PCSK9 and PWV in a cohort of heterozygous familial hypercholesterolemia (HeFH) subjects. In a previous step, HeFH patients were enrolled and LLT was prescribed according to guidelines. Biochemical analyses and PWV assessment were performed at baseline (T0), after 6 months of high-efficacy statin plus ezetimibe (T1) and after 6 months of PCSK9-i (T2). The PCSK9 levels were evaluated in 26 selected HeFH subjects at the three time points and 26 healthy subjects served as controls for the reference value for PCSK9 plasma levels. The PWV values decreased at each time point in HeFH subjects after LLT starting (8.61 ± 2.4 m/s, −8.7%; p < 0.001 vs. baseline at T1, and 7.9 ± 2.1 m/s, −9.3%; p < 0.001 vs. both T1 and baseline) and it was correlated to PCSK9 (r = 0.411, p = 0.03). The PCSK9 levels increased on statin/EZE therapy (+42.8% at T1) while it decreased after PCSK9-i was started (−34.4% at T2). We noted a significant relationship between PCSK9 levels and PWV changes at T1 and T2. In conclusion, PCSK9 levels were associated with baseline PWV values in HeFH subjects; moreover, we found that PCSK9 level variations seemed to be correlated with PWV changes on LLT. A longer observation time and wider sample size are needed to assess the potential role of PCSK9 plasma levels on the vascular function and remodelling, and to clarify the effects of PCSK9-i in these pathways.

PCSK9 and Cardiovascular Disease in Individuals with Moderately Decreased Kidney Function

Background and objectives: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a key regulator of lipid homeostasis. Studies investigating the association between PCSK9 and cardiovascular disease in large cohorts of CKD patients are limited. Design, setting, participants, and measurements: The association of PCSK9 concentrations with prevalent and incident cardiovascular disease was investigated in 5,138 Caucasians of the German Chronic Kidney Disease study with a median follow-up of 6.5 years. Inclusion criteria were eGFR of 30-60 mL/min/1.73 m² or an eGFR>60 mL/min/1.73m² in the presence of overt proteinuria (urine albumin-creatinine ratio >300mg/g or equivalent). Prevalent cardiovascular disease was defined as history of non-fatal myocardial infarction, coronary artery bypass grafting, percutaneous transluminal coronary angioplasty, carotid arteries interventions and stroke. Incident major adverse cardiovascular disease events included death from cardiovascular causes, acute non-fatal myocardial infarction and non-fatal stroke. Results: Median PCSK9 concentration in the cohort was 285 ng/mL (interquartile range 231-346 ng/mL). There was no association between PCSK9 concentrations and baseline eGFR and albuminuria. With each 100 ng/ml increment of PCSK9, the odds for prevalent cardiovascular disease (n=1,284) was 1.22-fold (95%CI 1.12-1.34, p<0.001) higher in a model with extended adjustment for major confounders. This association was stronger in non-statin than statin-users (p-value for interaction=0.009). During follow-up 474 individuals experienced a major adverse cardiovascular disease event and participants in PCSK9 quartiles 2 to 4 had a 32%-47% higher risk compared to quartile 1 (p<0.05). Subgroup analysis revealed this association was restricted to those participants who already had cardiovascular disease at baseline (all HR>1.75, p<0.05). In addition, PCSK9 showed a valuable gain in classification accuracy both for prevalent cardiovascular disease (NRI=0.27, 95%CI:0.20-0.33) and incident major adverse cardiovascular disease events during follow-up (NRI=0.10, 95%CI:0.008-0.21) when added to an extended adjustment model. Conclusions: Our findings reveal no relation of PCSK9 with baseline eGFR and albuminuria, but a significant association between higher PCSK9 concentrations and risk of cardiovascular disease independent of traditional risk factors including LDL-cholesterol levels.

Lipoprotein oxidation may underlie the paradoxical association of low cholesterol with coronary atherosclerotic risk in rheumatoid arthritis

OBJECTIVE

To compare coronary plaque burden, proatherogenic cytokines, oxidized low-density lipoprotein (oxLDL), anti-oxLDL antibodies, lipoprotein(a)-cholesterol, and their relationships in patients with rheumatoid arthritis with low-density lipoprotein cholesterol (LDL-C)<1.8 mmol/L versus ≥1.8 mmol/L. Also, to study differences in inflammation and proprotein convertase subtilisin/kexin type-9 (PCSK9), which impacts LDL clearance, in patients with low versus high LDL-C.

METHODS

Computed tomography angiography evaluated coronary plaque (noncalcified, partially calcified, fully calcified, and high-risk plaque) in 150 patients from a single-center observational cohort. Ox-LDL, anti-oxLDL IgG, lipoprotein(a)-cholesterol, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), interleukin-6, tumor necrosis factor-α (TNF-α) and PCSK9 were measured. Analyses adjusted for Framingham general cardiovascular risk score, statin use, and high-density lipoprotein cholesterol.

RESULTS

Patients with LDL-C<1.8 mmol/L versus ≥1.8 mmol/L demonstrated: 1) higher likelihood of per-segment plaque (adjusted-OR = 1.67 [95%CI = 1.10-2.55], p = 0.017) and high-risk plaque presence (adjusted-OR 2.78 [95%CI = 1.06-7.29], p = 0.038); 2) greater anti-oxLDL titers (p = 0.020), which positively associated with TNF-α and likelihood of noncalcified, partially calcified and high-risk plaque presence only in patients with LDL-C<1.8 mmol/L (all p-for-interaction≤0.046); 3) increased lipoprotein(a)-cholesterol content (10.33% [8.11-12.54] versus 6.68% [6.10-7.25], p < 0.001), which positively associated with oxLDL (p < 0.001) and anti-oxLDL (p = 0.036); 4) higher interleukin-6 and PCSK9. No differences in CRP, ESR, or oxLDL were observed.

CONCLUSION

RA patients with LDL-C<1.8 mmol/L had more coronary plaque, higher anti-oxLDL titers and anti-oxLDL associated with plaque only in this group. It is possible the observed paradoxical association of low LDL-C with greater atherosclerosis may be related to higher production of the oxidation-prone lipoprotein(a)-cholesterol and anti-oxLDL antibodies, resulting in increased vascular LDL uptake and plaque formation.

Effects of PCSK9 Targeting: Alleviating Oxidation, Inflammation, and Atherosclerosis

Characterized as a chronic inflammatory disease of the large arteries, atherosclerosis is the primary cause of cardiovascular disease, the leading contributor of morbidity and mortality worldwide. Elevated plasma cholesterol levels and chronic inflammation within the arterial plaque are major mediators of plaque initiation, progression, and instability. In 2003, the protein PCSK9 (proprotein convertase subtilisin/kexin 9) was discovered to play a critical role in cholesterol regulation, thus becoming a key player in the mechanisms behind atherosclerotic plaque development. Emerging evidence suggests that PCSK9 could potentially have effects on atherosclerosis that are independent of cholesterol levels. The objective of this review was to discuss the role on PCSK9 in oxidation, inflammation, and atherosclerosis. This function activates proinflammatory cytokine production and affects oxidative modifications within atherosclerotic lesions, revealing its more significant role in atherosclerosis. Although a variety of evidence demonstrates that PCSK9 plays a role in atherosclerotic inflammation, the direct mechanism of involvement is still unknown, driving a gap in knowledge to such a predominant player in cardiovascular disease. Investigation of proteins structurally related to PCSK9 may interestingly be the link in unveiling the mechanistic role of this protein’s involvement in oxidation and inflammation. Importantly, the unique structure of PCSK9 bears structural homology to a one‐of‐a‐kind domain found in the metabolic protein resistin, which is responsible for many of the same inflammatory outcomes as PCSK9. Closing this gap in knowledge of PCSK9`s role in atherosclerotic oxidation and inflammation will provide fundamental information for understanding, preventing, and treating cardiovascular disease.

Emerging Insights on the Diverse Roles of Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) in Chronic Liver Diseases: Cholesterol Metabolism and Beyond

Chronic liver diseases are commonly associated with dysregulated cholesterol metabolism. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a serine protease of the proprotein convertase family that is mainly synthetized and secreted by the liver, and represents one of the key regulators of circulating low-density lipoprotein (LDL) cholesterol levels. Its ability to bind and induce LDL-receptor degradation, in particular in the liver, increases circulating LDL-cholesterol levels in the blood. Hence, inhibition of PCSK9 has become a very potent tool for the treatment of hypercholesterolemia. Besides PCSK9 limiting entry of LDL-derived cholesterol, affecting multiple cholesterol-related functions in cells, more recent studies have associated PCSK9 with various other cellular processes, including inflammation, fatty acid metabolism, cancerogenesis and visceral adiposity. It is increasingly becoming evident that additional roles for PCSK9 beyond cholesterol homeostasis are crucial for liver physiology in health and disease, often contributing to pathophysiology. This review will summarize studies analyzing circulating and hepatic PCSK9 levels in patients with chronic liver diseases. The factors affecting PCSK9 levels in the circulation and in hepatocytes, clinically relevant studies and the pathophysiological role of PCSK9 in chronic liver injury are discussed.

Influence of lipid-lowering drugs on inflammation: what is yet to be done?

Atherosclerosis is a chronic inflammatory disease that is associated with risk of cardiovascular events. The best-characterised and well-standardised clinical indicator of inflammation is C-reactive protein. Current evidence-based drug therapies for prevention and treatment of cardiovascular diseases are mainly focused on reduction of low-density lipoprotein cholesterol. However, these drugs do not provide sufficient protection against recurrent cardiovascular events. One of the possible mechanisms behind this recurrence might be the persistence of residual inflammation. For the most commonly used lipid-lowering drugs, the statins, their reduction of cardiovascular events goes beyond lowering of low-density lipoprotein cholesterol. Here, we review the effects of these lipid-lowering drugs on inflammation, considering statins, ezetimibe, fibrates, niacin, proprotein convertase subtilisin/kexin type 9 inhibitors, bempedoic acid, ethyl eicosapentaenoic acid and antisense oligonucleotides. We focus in particular on C-reactive protein, and discuss how the effects of the statins might be related to reduced rates of cardiovascular events.

PCSK9 inhibitors revisited: Effectiveness and safety of PCSK9 inhibitors in a real-life Spanish cohort

INTRODUCTION

Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) have emerged as a therapeutic option for patients with hypercholesterolemia who do not attain low-density lipoprotein cholesterol (LDL-C) goals and/or are intolerant to other lipid-lowering drugs. Our aim was to analyze the effectiveness and safety of PCSK9i in routine clinical practice and factors related to poor outcomes.

MATERIALS AND METHODS

We conducted an ambispective study in 115 patients who recieved alirocumab or evolocumab, in a tertiary level hospital. From February 2017 to April 2020, patients were recruited and followed up for a median of 20.4 months. The main outcomes were relative reduction in LDL-C, percentage of patients achieving the therapeutic goals established by 2016 ESC/EAS guidelines, incidence of major cardiovascular events (MACEs) and drug-related adverse events (ADRs).

RESULTS

The median LDL-C achieved was 57.0 mg/dL (relative reduction of 59.9% from baseline, p< 0.001). After adjusting for confounders, smaller LDL-C reductions were related to female sex, absence of concomitant lipid-lowering therapy and treatment with alirocumab. Overall, 84.6% of the patients achieved the therapeutic goals. During follow-up, 7 MACEs were detected. ADRs, generally considered mild, affected 38.1% of the participants (mainly mialgias and arthralgias) and triggered discontinuations in 8.7% of cases.

CONCLUSIONS

PCSK9i are effective and safe, although certain factors may influence their effectiveness. Interestingly, our results suggest that alirocumab and evolocumab may not be therapeutic equivalents, as initially suggested.

PCSK9 as a new player in cancer: New opportunity or red herring?

Initially described as a factor involved in liver regeneration and neuronal differentiation, proprotein convertase subtilisin/kexin type 9 (PCSK9) has become one of the key regulators of low-density lipoprotein cholesterol. Besides that, a number of studies have suggested PCSK9 may play a role in cancer biology. This is particularly true for gastroenteric (gastric and liver cancers) and lung cancers, where higher PCSK9 levels were associated with the increased ability of the tumor to develop and give metastasis as well as with reduced overall survival. Accordingly, monoclonal antibodies blocking PCSK9 were recently shown to synergize with immunotherapy in different types of cancers to achieve tumor growth suppression through an increased intratumoral infiltration of cytotoxic T cells. Anti-PCSK9 vaccines have been tested in animal models with encouraging results only in colon carcinoma. As most of this evidence is based on pre-clinical studies, this has led to some controversies and inconsistencies, thus suggesting that additional research is needed to clarify the topic. Finally, modulation of intracellular PCSK9 levels by silencing RNA (siRNA) may help understand the physiological and pathological mechanisms of PCSK9.

Efficacy and Safety of Lipid-Lowering Drugs of Different Intensity on Clinical Outcomes: A Systematic Review and Network Meta-Analysis

There have been many meta-analyses for statins, ezetimibe and proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) to evaluate clinical outcomes, but the efficacy and safety of different intensity of these three drugs on clinical outcomes was absent. PCSK9i, ezetimibe, and statins were divided into seven interventions as follows: including PCSK9i + high-intensity statins (P9i+HT), PCSK9i + moderate-intensity statins (P9i+MT), ezetimibe + high-intensity statins (Eze+HT), ezetimibe + moderate-intensity statins (Eze+MT), high-intensity statins (HT), moderate-intensity statins (MT), and low-intensity statins (LT). The risk ratios (RR) and 95% confidence intervals (CI) were calculated to evaluate the clinical outcomes in all randomized controlled trials included. In traditional meta-analysis, the more intensive treatment had a lower risk of all-cause mortality (RR 0.91, 95% CI 0.88-0.95), cardiovascular mortality (RR 0.89, 95% CI 0.86-0.92), myocardial infarction (RR 0.79, 95% CI 0.77-0.81), coronary revascularization (RR 0.80, 95% CI 0.76-0.84), and cerebrovascular events (RR 0.84, 95% CI 0.80-0.88) compared with the less intensive treatment. However, the more intensive treatment had a higher risk of new-onset diabetes (RR 1.08, 95% CI 1.04-1.12). The network meta-analysis demonstrated that P9i+HT, P9i+MT, HT, and MT were significantly associated with a risk reduction in coronary revascularization and cerebrovascular events compared with PLBO. LT could effectively reduce the risk of cardiovascular mortality (RR 0.71, 95% CI 0.54-0.92), MI (RR 0.67, 95% CI 0.54-0.82), and coronary revascularization (RR 0.77, 95% CI 0.65-0.91) compared with PLBO. P9i+HT was superior to HT in reducing the risk of MI (RR 0.78, 95% CI 0.68-0.90), coronary revascularization (RR 0.84, 95% CI 0.73-0.96), and cerebrovascular events (RR 0.78, 95% CI 0.64-0.95). However, compared with PLBO, P9i+HT, HT, and MT could increase the risk of new-onset diabetes (RR 1.23, 95% CI 1.11-1.37; RR 1.23, 95% CI 1.14-1.33; RR 1.09, 95% CI 1.02-1.15, respectively). In conclusion, PCSK9i added to background statins may be recommended as preferred lipid-lowering therapy, and did not increase the additional risk of new-onset diabetes. The safety and efficacy of ezetimibe was not superior to that of statins. LT can be recommended as the initial therapy.

Genome-Wide Association of Proprotein Convertase Subtilisin/Kexin Type 9 Plasma Levels in the ELSA-Brasil Study

Pharmacological inhibition of PCSK9 (proprotein convertase subtilisin/kexin type 9) is an established therapeutic option to treat hypercholesterolemia, and plasma PCSK9 levels have been implicated in cardiovascular disease incidence. A number of genetic variants within the PCSK9 gene locus have been shown to modulate PCSK9 levels, but these only explain a very small percentage of the overall PCSK9 interindividual variation. Here we present data on the genetic association structure between PCSK9 levels and genom-wide genetic variation in a healthy sample from the general population. We performed a genome-wide association study of plasma PCSK9 levels in a sample of Brazilian individuals enrolled in the Estudo Longitudinal de Saude do Adulto cohort (n=810). Enrolled individuals were free from cardiovascular disease, diabetes and were not under lipid-lowering medication. Genome-wide genotyping was conducted using the Axiom_PMRA.r3 array, and imputation was performed using the TOPMED multi-ancestry sample panel as reference. Total PCSK9 plasma concentrations were determined using the Quantikine SPC900 ELISA kit. We observed two genome-wide significant loci and seven loci that reached the pre-defined value of p threshold of 1×10⁻⁶. Significant variants were near KCNA5 and KCNA1, and LINC00353. Genetic variation at the PCSK9 locus was able to explain approximately 4% of the overall interindividual variations in PCSK9 levels. Colocalization analysis using eQTL data suggested RWDD3, ATXN7L1, KCNA1, and FAM177A1 to be potential mediators of some of the observed associations. Our results suggest that PCSK9 levels may be modulated by trans genetic variation outside of the PCSK9 gene and this may have clinical implications. Understanding both environmental and genetic predictors of PCSK9 levels may help identify new targets for cardiovascular disease treatment and contribute to a better assessment of the benefits of long-term PCSK9 inhibition.

Lipoprotein(a): Knowns, unknowns and uncertainties

Over the last 10 years, there have been advances on several aspects of lipoprotein(a) which are reviewed in the present article. Since the standard immunoassays for measuring lipoprotein(a) are not fully apo(a) isoform-insensitive, the application of an LC-MS/MS method for assaying molar concentrations of lipoprotein(a) has been advocated. Genome wide association, epidemiological, and clinical studies have established high lipoprotein(a) as a causal risk factor for atherosclerotic cardiovascular diseases (ASCVD). However, the relative importance of molar concentration, apo(a) isoform size or variants within the LPA gene is still controversial. Lipoprotein(a)-raising single nucleotide polymorphisms has not been shown to add on value in predicting ASCVD beyond lipoprotein(a) concentrations. Although hyperlipoproteinemia(a) represents an important confounder in the diagnosis of familial hypercholesterolemia (FH), it enhances the risk of ASCVD in these patients. Thus, identification of new cases of hyperlipoproteinemia(a) during cascade testing can increase the identification of high-risk individuals. However, it remains unclear whether FH itself increases lipoprotein(a). The ASCVD risk associated with lipoprotein(a) seems to follow a linear gradient across the distribution, regardless of racial subgroups and other risk factors. The inverse association with the risk of developing type 2 diabetes needs consideration as effective lipoprotein(a) lowering therapies are progressing towards the market. Considering that Mendelian randomization analyses have identified the degree of lipoprotein(a)-lowering that is required to achieve ASCVD benefit, the findings of the ongoing outcome trial with pelacarsen will clarify whether dramatically lowering lipoprotein(a) levels can reduce the risk of ASCVD.

Trends in PCSK9 Inhibitor Prescriptions before and after the Price Reduction in Patients with Atherosclerotic Cardiovascular Disease

BACKGROUND

Proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors reduce low-density lipoprotein (LDL) cholesterol and cardiovascular event rates, yet due to their high price remain underutilized and difficult to prescribe in clinical practice. In March 2018, their price was significantly reduced. We evaluated whether the price reduction would improve prescribing patterns of PCSK9 inhibitors in eligible patients with atherosclerotic cardiovascular disease (ASCVD).

METHODS

We identified the number of eligible ASCVD patients and those prescribed a PCSK9 inhibitor for each year between July 2015 and December 2019. Patient demographics and clinical characteristics for those prescribed a PCSK9 inhibitor were extracted from their electronic health record.

RESULTS

In total 1059 patients of eligible patients received a new prescription for a PCSK9 inhibitor. From 2015 to 2019, the rate of new prescriptions among eligible patients increased from 0.5 to 3.3% (p < 0.001) and continuation rates increased from 18 to 60% (p < 0.001). Following the price reduction, patients who were prescribed a PCSK9 inhibitor were younger and more likely to be female, but less likely to have Medicare insurance.

CONCLUSIONS

Despite the reduction in the cost of PCSK9 inhibitors, most eligible patients are not prescribed one. The reduction in cost has improved adherence, primarily in patients with commercial insurance. Older patients and those on Medicare still face significant barriers in accessing a PCSK9 inhibitor. Further reductions in the price of the PCSK9 inhibitors are needed as is further study of the barriers that exist in prescribing one.

PCSK9 and inflammation. Maybe a role in autoimmune diseases? Focus on rheumatoid arthritis and systemic lupus erythematosus

Despite a clear epidemiological link between autoimmune disease and cardiovascular (CV) risk exists, pathophysiological explanations are extremely complex and far from being elucidated. Dysregulation of metabolic pathways and chronic low-grade inflammation represent common pathways, but CV risk still remains underestimated in patients with autoimmune diseas. Among different candidate mediators, pro-protein convertase subtilisin/kexin type 9 (PCSK9) is attracting a growing attention, due to a combined effect on lipid metabolism and inflammatory response. Study on PCSK9 inhibitors have established a clear benefit on CV outcome without an established effect on inflammation. Conversely, evidence from sepsis and HIV infection strongly support a pro-inflammatory role of PCSK9. Still uncertain is instead the role of PCSK9 in autoimmune disease. So far reported clinical findings are controversial and likely reflect the poor knowledge of PCSK9 activity on monocyte/macrophage migration and activation. The complex signaling network around PCSK9 synthesis and metabolism may also have a role, especially concerning the involvement of scavenger receptors such as CD36. Such complexity in PCSK9 signaling seems particularly evident in autoimmune disease model. This would also potentially explain the observed independency between lipid profile and PCSK9 levels, the so-called "lipid paradox". In this narrative review we will summarize the current knowledge about the complex network of PCSK9 signaling. We will focus of upstream and downstream pathways with potential implication in autoimmune disease and potential effects of PCSK9 inhibiting strategies.

Cardiovascular disease in diabetes, beyond glucose

Despite the decades-old knowledge that diabetes mellitus is a major risk factor for cardiovascular disease, the reasons for this association are only partially understood. While this association is true for both type 1 and type 2 diabetes, different pathophysiological processes may be responsible. Lipids and other risk factors are indeed important, whereas the role of glucose is less clear. This lack of clarity stems from clinical trials that do not unambiguously show that intensive glycemic control reduces cardiovascular events. Animal models have provided mechanisms that link diabetes to increased atherosclerosis, and evidence consistent with the importance of factors beyond hyperglycemia has emerged. We review clinical, pathological, and animal studies exploring the pathogenesis of atherosclerosis in humans living with diabetes and in mouse models of diabetes. An increased effort to identify risk factors beyond glucose is now needed to prevent the increased cardiovascular disease risk associated with diabetes.

Infections as Novel Risk Factors of Atherosclerotic Cardiovascular Diseases: Pathophysiological Links and Therapeutic Implications

Atherosclerotic cardiovascular diseases (ASCVD) are the major cause of mortality worldwide. Despite the continuous progress in ASCVD therapy, the residual risk persists beyond the management of traditional risk factors. Several infections including Helicobacter pylori infection, periodontal disease, and viral infections are associated with the increased risk of ASCVD, both directly by damage to the heart muscle and vasculature, and indirectly by triggering a systemic proinflammatory state. Hence, beyond the optimal management of the traditional ASCVD risk factors, infections should be considered as an important non-classical risk factor to enable early diagnosis and appropriate treatment. Here, we summarized the currently available evidence regarding the role of inflammation in ASCVD and the association between the particular infections and pathogens (Helicobacter pylori, periodontal disease, pneumonia, Cytomegalovirus, Human immunodeficiency virus, Herpes simplex virus, and severe acute respiratory syndrome coronavirus 2) on the development and progression of ASCVD. We also speculated about the potential therapeutic implications of the anti-inflammatory and anti-infective drugs on ASCVD outcomes, including drugs routinely administered in patients with ASCVD (statins, P2Y12 receptor inhibitors, and angiotensin-converting enzyme inhibitors/angiotensin receptor blockers) and novel strategies aiming at residual risk reduction (colchicine, anti-cytokine drugs, and methotrexate). Considering the emerging association between infections and ASCVD, it is crucial to determine the possible advantages of infection prevention and treatment in patients with ASCVD.

Antibody-Based Therapeutics for Atherosclerosis and Cardiovascular Diseases

Cardiovascular disease is the leading cause of death worldwide, and its prevalence is increasing due to the aging of societies. Atherosclerosis, a type of chronic inflammatory disease that occurs in arteries, is considered to be the main cause of cardiovascular diseases such as ischemic heart disease or stroke. In addition, the inflammatory response caused by atherosclerosis confers a significant effect on chronic inflammatory diseases such as psoriasis and rheumatic arthritis. Here, we review the mechanism of action of the main causes of atherosclerosis such as plasma LDL level and inflammation; furthermore, we review the recent findings on the preclinical and clinical effects of antibodies that reduce the LDL level and those that neutralize the cytokines involved in inflammation. The apolipoprotein B autoantibody and anti-PCSK9 antibody reduced the level of LDL and plaques in animal studies, but failed to significantly reduce carotid inflammation plaques in clinical trials. The monoclonal antibodies against PCSK9 (alirocumab, evolocumab), which are used as a treatment for hyperlipidemia, lowered cholesterol levels and the incidence of cardiovascular diseases. Antibodies that neutralize inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-17, and IL-12/23) have shown promising but contradictory results and thus warrant further research.

Antiplatelet Effects of PCSK9 Inhibitors in Primary Hypercholesterolemia

Proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitors are a novel group of hypolipidemic drugs that are recommended particularly for high-risk hypercholesterolemia patients, including those with primary hypercholesterolemia (PH), where lifelong exposure to high low-density lipoprotein (LDL) cholesterol levels results in an elevated risk of atherosclerosis at an early age. The onset and progression of atherosclerosis is significantly influenced by activated platelets. Oxidized LDL influences platelet activation by interacting with their surface receptors and remodeling the composition of their cell membrane. This results in platelet aggregation, endothelial cell activation, promotion of inflammation and oxidative stress, and acceleration of lipid accumulation in atherosclerotic plaques. PCSK9 inhibitors reduce platelet activation by both significantly lowering LDL levels and reducing the LDL receptor-mediated activation of platelets by PCSK9. They also work synergistically with other hypolipidemic and antithrombotic drugs, including statins, ezetimibe, acetylsalicylic acid, clopidogrel, and ticagrelor, which enhances their antiplatelet and LDL-lowering effects. In this review, we summarize the currently available evidence on platelet hyperreactivity in PH, the effects of PCSK9 inhibitors on platelets, and their synergism with other drugs used in PH therapy.

PCSK9 genetic (rs11591147) and epigenetic (DNA methylation) modifications associated with PCSK9 expression and serum proteins in CAD patients

INTRODUCTION

Proprotein convertase subtilisin/kexin type 9 (PCSK9) genetic polymorphisms play a significant role in cholesterol homeostasis. Therefore, we aimed to investigate the association of PCSK9 genetic variations NM_174936.3:c.137G>T (R46L, rs11591147) and NM_174936.3:c.1120G>T (D374Y, rs137852912), as well as promoter DNA methylation status, with mRNA expression and circulating serum protein levels in coronary artery disease (CAD) patients.

METHODS

The present study includes 300 CAD cases and 300 controls from South India. Biochemical assays were performed using commercially available kits. PCSK9 rs11591147 and rs137852912 polymorphisms were analyzed by the polymerase chain reaction (PCR)-restriction fragment length polymorphism method, whereas promoter DNA methylation status and gene expression were determined using methylation specific PCR and quantitative PCR respectively.

RESULTS

The genotypic distribution of PCSK9 rs11591147 revealed that individuals with the TT-genotype and T-allele have a reduced risk for CAD. Furthermore, patients with the PCSK9 rs11591147 TT genotype have a significantly lower total cholesterol and low-density lipoprotein-cholesterol levels and also higher high-density lipoprotein-cholesterol levels than individuals with the GG genotype. Logistic regression analysis has shown that the GG and GT (p = 1.51 × 10^-8 , p = 1.47 × 10^-9 ) genotypes predicted the risk for CAD with an odds ratio of 5.8 and 7.3 respectively. In addition, individuals with the TT genotype were hypermethylated at promoter DNA of PCSK9, resulting in lower mRNA expression and circulating serum proteins than in individuals with the GG genotype. In silico analyses revealed that rs11591147 T-allele has protein destabilizing capacity.

CONCLUSIONS

In conclusion, the present study indicates that the PCSK9 gene expression and circulating serum protein levels are not only associated with rs11591147 genotype, but also with promoter DNA methylation. Furthermore, the findings with respect to both single nucleotide polymorphism and promoter DNA methylation may open avenues for novel treatment possibilities targeting PCSK9 for CAD management.

Proprotein Convertase Subtilisin/Kexin Type 9: A View beyond the Canonical Cholesterol-Lowering Impact

Proprotein convertase subtilisin/kexin type 9 (PCSK9), mainly synthetized and released by the liver, represents one of the key regulators of low-density lipoprotein cholesterol. Although genetic and interventional studies have demonstrated that lowering PCSK9 levels corresponds to a cardiovascular benefit, identification of non-cholesterol-related processes has emerged since its discovery. Besides liver, PCSK9 is also expressed in many tissues (eg, intestine, endocrine pancreas, and brain). The aim of the present review is to describe and discuss PCSK9 pathophysiology and possible non-lipid-lowering effects whether already extensively characterized (eg, inflammatory burden of atherosclerosis, triglyceride-rich lipoprotein metabolism, and platelet activation), or to be unraveled (eg, in adipose tissue). The identification of novel transcriptional factors in the promoter region of human PCSK9 (eg, ChREBP) characterizes new mechanisms explaining how controlling intrahepatic glucose may be a therapeutic strategy to reduce cardiovascular risk in type 2 diabetes. Finally, the evidence describing PCSK9 as involved in cell proliferation and apoptosis raises the possibility of this protein being involved in cancer risk.

Clinical development of bempedoic acid: phase 2 and phase 3 clinical trials

We review all the phase II and III studies carried out with bempedoic acid at the dose of 180mg, alone or in combination with different lipid-lowering drugs and in different subgroups of patients that unequivocally show the efficacy and safety of the drug. We point out some of the potential advantages of its use in clinical practice in patients with statin intolerance and the efficacy in reducing LDL-c when combined with statins, and with statins and ezetimibe, as well as in reducing inflammation markers pending the results of the CV Clear Outcomes trial that will end in 2022.