Effect of monoclonal antibodies to PCSK9 on high-sensitivity C-reactive protein levels: a meta-analysis of 16 randomized controlled treatment arms

Mendelian randomization-based observational cohort study on drug targets: Impact of antihypertensive and lipid-lowering therapies on inflammatory cytokines

This study assesses the causal effects of antihypertensive and lipid-lowering drugs on inflammatory cytokines using a Mendelian randomization (MR) approach. We conducted a drug-targeted MR analysis using data from large-scale genome-wide association studies and eQTL datasets. SNPs near drug target genes served as instrumental variables to investigate the impact of antihypertensive (angiotensin-converting enzyme inhibitors [ACEIs], ARBs) and lipid-lowering drugs (HMGCR inhibitors, proprotein convertase subtilisin/Kexin type 9 [PCSK9] inhibitors, Niemann-Pick C1-like 1 inhibitors) on inflammatory cytokines. Sensitivity analyses, including leave-one-out and MR-Egger tests, were performed to confirm the robustness of the findings. ACEIs were associated with decreased levels of IL-1β, TNF-α, and CRP. ARBs did not show significant effects on inflammatory cytokines. HMGCR inhibitors significantly reduced MCP-1, MIP-1β, TNF-α, and IFN-γ, while PCSK9 inhibitors were linked to reductions in IL-1β and IL-6. Sensitivity analyses supported the reliability of these findings. The study demonstrated distinct anti-inflammatory effects of ACEIs, HMGCR inhibitors, and PCSK9 inhibitors. These findings support the potential use of these drugs to mitigate inflammation-related complications in patients with chronic conditions.

Exploring neutrophils as therapeutic targets in cardiometabolic diseases

Current therapies for diabetes and atherosclerotic cardiovascular diseases (ACVDs) mainly target metabolic risk factors, but often fall short in addressing systemic inflammation, a key driver of disease onset and progression. Advances in our understanding of the biology of neutrophils, the cells that are principally involved in inflammatory situations, have highlighted their pivotal role in cardiometabolic diseases. Yet, neutrophils can reprogram their immune-metabolic functions based on the energetic substrates available, thus influencing both tissue homeostasis and the resolution of inflammation. In this review, we examine the effects of canonical therapies for cardiometabolic diseases on the key molecular pathways through which neutrophils respond to inflammatory stimuli. In addition, we explore potential synergies between these established therapeutic approaches and the anti-inflammatory therapies being evaluated for repurposing in the treatment of cardiometabolic diseases.

Evaluating the effect of the antiPCSK9 vaccine on systemic inflammation and oxidative stress in an experimental mouse model

BACKGROUND

To investigate whether the antiPCSK9 vaccine can affect the CRP and oxidative stress (OS) during acute systemic inflammation.

METHODS

Male albino mice were randomly divided into three groups: non-treated mice (the sham group), treated with a nonspecific stimulator of the immune response - Freund's complete adjuvant (CFA; the CFA group), and vaccinated mice treated with CFA (the vaccine group). The vaccine group was subcutaneously immunized with the antiPCSK9 formulation, 4 × in bi-weekly intervals. To induce inflammation, all mice were subjected to the CFA challenge after the vaccination plan. The hsCRP level and OS status were evaluated by a mouse CRP ELISA kit and the pro-oxidant antioxidant balance (PAB) assay, respectively.

RESULTS

The vaccine induced a high-titter IgG antiPCSK9 antibody, which was accompanied with a significant PCSK9 reduction (-24.7% and -28.5% compared with the sham and CFA group, respectively), and the inhibition of PCSK9/LDLR interaction (-27.8% and -29.4%, respectively). hsCRP was significantly increased in the vaccine and CFA groups by 225% and 274% respectively, when compared with the sham group; however, it was non-significantly decreased (-18%; p = 0.520) in the vaccine group in comparison with the CFA group. The PAB values indicated that OS was significantly increased in the CFA group (by 72.7%) and the vaccine group (by 76%) when compared to the sham group; however, there was no significant difference in the PAB values between the vaccine and CFA groups.

CONCLUSION

The antiPCSK9 vaccine failed to significantly reduce the serum hs-CRP and OS induced in the CFA-challenged albino mice.

Immune-Mediated Inflammatory Diseases, Dyslipidemia, and Cardiovascular Risk: A Complex Interplay

Individuals with autoimmune inflammatory diseases, such as systemic lupus erythematosus, rheumatoid arthritis, and psoriasis, are at increased risk for cardiovascular disease. While these diseases share common features of systemic inflammation, the impact of individual autoimmune inflammatory conditions on circulating lipids and lipoproteins varies by specific disease, disease activity, and the immune-suppressing medications used to treat these conditions. A common feature observed in many autoimmune inflammatory diseases is the development of a proatherogenic dyslipidemic state, characterized by dysfunctional HDLs (high-density lipoproteins) and increased oxidation of LDLs (low-density lipoproteins). Various disease-modifying antirheumatic drugs also have complex and variable effects on lipids, and it is critical to take this into consideration when evaluating lipid-related risk in individuals with immune-mediated inflammatory conditions. This review aims to critically evaluate the current understanding of the relationship between immune-mediated inflammatory diseases and dyslipidemia, the underlying mechanisms contributing to atherogenesis, and the impact of various pharmacotherapies on lipid profiles and cardiovascular risk. We also discuss the role of lipid-lowering therapies, particularly statins, in managing residual risk in this high-risk population and explore the potential of emerging therapies with complementary anti-inflammatory and lipid-lowering effects.

Role of Statins in Oral and Maxillofacial Surgery: A Literature Review

In recent years, there has been a notable increase in interest in the use of statins in oral and maxillofacial surgery. The purpose of this literature review was to look into the effectiveness of statins in this area. Using a set of keywords, a thorough search of electronic databases was carried out, including PubMed, Scopus, Web of Science, Excerpta Medica database (EMBASE), and ProQuest. The papers considered were just those published in the English language between January 2012 and January 2024. Only human studies were taken into consideration; those involving animals were not. For the final analysis that assessed the use of statins in dentistry, a total of 30 papers were chosen. The designs, sample sizes, and materials employed in the experiments varied. According to the research, statins improve bone regeneration, have antiviral and antibacterial qualities, and work well as a therapeutic adjuvant for the treatment of periodontal disease. The analysis of the literature indicates that statins may be beneficial for treating periodontal disease, promoting bone regeneration, and improving oral health in the context of oral and maxillofacial surgery. Nevertheless, more investigation is required to completely comprehend the function of statins in this domain.

Significance of Persistent Inflammation in Patients With Chronic Coronary Syndrome: Insights From the REAL-CAD Study

Background

The prognostic implications of persistent low-grade inflammation in patients with chronic coronary syndrome (CCS) are underexplored. The REAL-CAD (Randomized Evaluation of Aggressive or Moderate Lipid Lowering Therapy with Pitavastatin in Coronary Artery Disease) study demonstrated the benefit of higher intensity pitavastatin in Japanese patients with CCS.

Objectives

This prespecified subanalysis of the REAL-CAD study aimed to assess the prognostic effect of the persistent low-grade inflammation represented by high-sensitivity C-reactive protein (hs-CRP) in CCS patients.

Methods

The present analysis involved patients without events until 6 months after randomization and whose hs-CRP levels were available at baseline and 6 months (n = 10,460). The primary endpoint was the composite of cardiovascular mortality, myocardial infarction, stroke, and unstable angina hospitalization. Landmark analyses evaluated the prognostic impact of continuous inflammation in 4 groups based on the median levels of hs-CRP (0.5 mg/L for both) at baseline and 6 months. The 4 groups included patient with persistently low, elevated (increased), reduced, and persistently high hs-CRP.

Results

Adjusted Cox proportional hazard analyses demonstrated an increased risk of the primary endpoint in the group with persistently high hs-CRP when compared to the group with persistently low hs-CRP as a reference (adjusted HR: 1.48, 95% CI: 1.18-1.89; P = 0.001), but with a similar risk in the group with elevated (HR: 1.07, 95% CI: 0.77-1.49, P = 0.68) and reduced (HR: 0.92; 95% CI: 0.66-1.27; P = 0.60) hs-CRP.

Conclusions

The study shows that persistent low-grade inflammation is associated with poor outcomes and underscores the need to address residual inflammatory risk in CCS patients. (Randomized Evaluation of Aggressive or Moderate Lipid Lowering Therapy With Pitavastatin in Coronary Artery Disease [REAL-CAD]; NCT01042730).

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.

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.

Long-Term Efficacy and Tolerability of PCSK9 Targeted Therapy: A Review of the Literature

Increased plasma levels of low-density lipoprotein cholesterol (LDL-C) are causally associated with atherosclerotic cardiovascular disease (ASCVD), and statins that lower LDL-C have been the cornerstone of ASCVD prevention for decades. However, guideline-recommended LDL-C targets are not achieved in about 60% of statin users. Proprotein convertase subtilisin/kexin type 9 (PCSK9)-targeted therapy effectively lowers LDL-C levels and has been shown to reduce ASCVD risk. A growing body of scientific and clinical evidence shows that PCSK9-targeted therapy offers an excellent safety and tolerability profile with a low incidence of side effects in the short term. In this review, we present and discuss the current clinical and scientific evidence pertaining to the long-term efficacy and tolerability of PCSK9-targeted therapy.

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.

Established and Emerging Lipid-Lowering Drugs for Primary and Secondary Cardiovascular Prevention

Despite treatment with statins, patients with elevated low-density lipoprotein cholesterol (LDL-C) and triglycerides remain at increased risk for adverse cardiovascular events. Consequently, novel pharmaceutical drugs have been developed to control and modify the composition of blood lipids to ultimately prevent fatal cardiovascular events in patients with dyslipidaemia. This article reviews established and emerging lipid-lowering drugs regarding their mechanism of action, development stage, ongoing clinical trials, side effects, effect on blood lipids and reduction in cardiovascular morbidity and mortality. We conducted a keyword search to identify studies on established and emerging lipid modifying drugs. Results were summarized in a narrative overview. Established pharmaceutical treatment options include the Niemann-Pick-C1 like-1 protein (NPC1L1) inhibitor ezetimibe, the protein convertase subtilisin-kexin type 9 (PCSK9) inhibitors alirocumab and evolocumab, fibrates as peroxisome proliferator receptor alpha (PPAR-α) activators, and the omega-3 fatty acid icosapent ethyl. Statins are recommended as the first-line therapy for primary and secondary cardiovascular prevention in patients with hypercholesterinaemia and hypertriglyceridemia. For secondary prevention in hypercholesterinaemia, second-line options such as statin add-on or statin-intolerant treatments are ezetimibe, alirocumab and evolocumab. For secondary prevention in hypertriglyceridemia, second-line options such as statin add-on or statin-intolerant treatments are icosapent ethyl and fenofibrate. Robust data for these add-on therapeutics in primary cardiovascular prevention remains scarce. Recent biotechnological advances have led to the development of innovative small molecules (bempedoic acid, lomitapide, pemafibrate, docosapentaenoic and eicosapentaenoic acid), antibodies (evinacumab), antisense oligonucleotides (mipomersen, volanesorsen, pelcarsen, olezarsen), small interfering RNA (inclisiran, olpasiran), and gene therapies for patients with dyslipidemia. These molecules specifically target new cellular pathways, such as the adenosine triphosphate-citrate lyase (bempedoic acid), PCSK9 (inclisiran), angiopoietin-like 3 (ANGPTL3: evinacumab), microsomal triglyceride transfer protein (MTP: lomitapide), apolipoprotein B-100 (ApoB-100: mipomersen), apolipoprotein C-III (ApoC-III: volanesorsen, olezarsen), and lipoprotein (a) (Lp(a): pelcarsen, olpasiran). The authors are hopeful that the development of new treatment modalities alongside new therapeutic targets will further reduce patients' risk of adverse cardiovascular events. Apart from statins, data on new drugs' use in primary cardiovascular prevention remain scarce. For their swift adoption into clinical routine, these treatments must demonstrate safety and efficacy as well as cost-effectiveness in randomized cardiovascular outcome trials.

Nutrition, Nutraceuticals and Bioactive Compounds in the Prevention and Fight against Inflammation

Chronic low-grade systemic inflammation is a key factor involved in the pathogenesis of many diseases and their complications (Figure 1) [...].

Impact of ezetimibe on markers of inflammation in patients treated with statins: a systematic review

Statins are the primary pharmacological intervention to reduce LDL cholesterol; they significantly reduce inflammatory markers. Ezetimibe also reduces LDL cholesterol and reduces cardiovascular events when given on top of statin therapy. Whether ezetimibe, like statins, reduces markers of inflammation is less clear. We, therefore, conducted a systematic literature research addressing the impact of ezetimibe on CRP, TNFα and IL-6 when given on top of statin therapy. Our work indicates that overall ezetimibe reduces inflammation on top of statin treatment. However, available data are limited for CRP and even more so for TNFα and IL-6.

Innate Immunity System in Patients With Cardiovascular and Kidney Disease

With a global burden of 844 million, chronic kidney disease (CKD) is now considered a public health priority. Cardiovascular risk is pervasive in this population, and low-grade systemic inflammation is an established driver of adverse cardiovascular outcomes in these patients. Accelerated cellular senescence, gut microbiota-dependent immune activation, posttranslational lipoprotein modifications, neuroimmune interactions, osmotic and nonosmotic sodium accumulation, acute kidney injury, and precipitation of crystals in the kidney and the vascular system all concur in determining the unique severity of inflammation in CKD. Cohort studies documented a strong link between various biomarkers of inflammation and the risk of progression to kidney failure and cardiovascular events in patients with CKD. Interventions targeting diverse steps of the innate immune response may reduce the risk of cardiovascular and kidney disease. Among these, inhibition of IL-1β (interleukin-1 beta) signaling by canakinumab reduced the risk for cardiovascular events in patients with coronary heart disease, and this protection was equally strong in patients with and without CKD. Several old (colchicine) and new drugs targeting the innate immune system, like the IL-6 (interleukin 6) antagonist ziltivekimab, are being tested in large randomized clinical trials to thoroughly test the hypothesis that mitigating inflammation may translate into better cardiovascular and kidney outcomes in patients with CKD.

Chronic PCSK9 inhibitor therapy leads to sustained improvements in endothelial function, arterial stiffness, and microvascular function

BACKGROUND

Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) effectively decrease low-density lipoprotein cholesterol (LDL-C) and reduce cardiovascular events in patients at very high cardiovascular risk. Recent short-term studies suggest a partially LDL-C independent beneficial effect of PCSK9 inhibitor (PCSK9i) therapy on endothelial function and arterial stiffness, whereas it is unknown if this effect persists and what the effect is on microcirculation.

OBJECTIVE

To investigate the effects of PCSK9i therapy on vascular parameters beyond its lipid lowering effect.

METHODS

In this prospective trial, 32 patients at very high cardiovascular risk and indication for PCSK9i therapy were included. Measurements were performed at baseline and after 6 months of PCSK9i treatment. Endothelial function was assessed as flow-mediated dilation (FMD). Arterial stiffness was measured as pulse wave velocity (PWV) and aortic augmentation index (AIx). Peripheral tissue oxygenation (StO₂) as a marker of microvascular function was assessed at the distal extremities using near-infrared spectroscopy camera.

RESULTS

Six months of PCSK9i therapy decreased LDL-C levels from 141 ± 54 to 60 ± 30 mg/dl (-56 ± 21 %, p < 0.001), FMD significantly increased from 5.4 ± 1.7 % to 6.4 ± 1.9 % (+19 ± 10 %, p < 0.001), PWV decreased in male patients significantly from 8.9 ± 2.1 to 7.9 ± 1.5 m/s (-12 ± 9 %, p = 0.025). AIx decreased from 27.1 ± 10.4 % to 23.0 ± 9.7 % (-16 ± 14 %, p < 0.001), StO₂ significantly increased from 67 ± 12 % to 71 ± 11 % (+7 ± 6 %, p = 0.012). Brachial and aortic blood pressure showed no significant changes after six months. There was no correlation between LDL-C reduction and changes in vascular parameters.

CONCLUSIONS

Chronic PCSK9i therapy is associated with sustained improvements in endothelial function, arterial stiffness, and microvascular function independent from lipid lowering.

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.

Coffee or tea: Anti-inflammatory properties in the context of atherosclerotic cardiovascular disease prevention

Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of premature death worldwide. Inflammation and its biomarkers, like C-reactive protein (CRP), among the risk factors, such as hypertension, lipid disorders, and diabetes, may be also responsible for the residual cardiovascular disease (CVD) risk. Modern lipid-lowering treatment with statins, ezetimibe, PCSK9 inhibitors, or bempedoic acid does not fully protect against inflammation. The recommendations of the International Lipid Expert Panel (ILEP) indicate selected nutraceuticals with anti-inflammatory properties. Diet may have a significant impact on inflammation. Especially interesting in the context of inflammation is the consumption of coffee and tea. These drinks in many observational studies significantly reduced cardiovascular risk and mortality. The question is whether the anti-inflammatory effects of these drinks contribute significantly to the observed clinical effects. Thus, in this narrative review, we primarily discuss the anti-inflammatory properties of consuming tea and coffee. Based on a comprehensive analysis of the studies and their meta-analyses, inconsistent results were obtained, which makes it impossible to conclusively state how clinically significant the potential anti-inflammatory properties of black and green tea and coffee are. A number of confounding factors can cause the inconsistency of the available results. Consumption of tea and coffee appears to increase adiponectin concentrations, decrease reactive oxygen species, decrease low density lipoprotein (LDL) cholesterol concentrations (effect of green tea, etc.). Despite the still uncertain anti-inflammatory effect of tea and coffee, we recommend their consumption as a part of the healthy diet.

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.

SIRT3 mediates the effects of PCSK9 inhibitors on inflammation, autophagy, and oxidative stress in endothelial cells

Background: Proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitors (i) are a class of lipid-lowering drugs suggested to hold a plethora of beneficial effects independent of their LDL cholesterol-lowering properties. However, the mechanism underlying such observations is debated. Methods: Human aortic endothelial cells (TeloHAEC) were pre-treated with 100 µg/mL of the PCSK9i evolocumab and then exposed to 20 ng/mL of IL-6, a major driver of cardiovascular diseases (CVD), in both naïve state and after siRNA-mediated suppression of the NAD-dependent deacetylase sirtuin-3 (SIRT3). Inflammation, autophagy, and oxidative stress were assessed through Western Blots, ELISAs, and/or immunofluorescence coupled by flow cytometry. To explore the human relevance of the findings, we also evaluated the expression of IL-6, SIRT3, IL-1β, the ratio LC3B II/I, and PCSK9 within the plaques of patients undergoing carotid endarterectomy (n=277), testing possible correlations between these proteins. Results: PCSK9i improved a range of phenotypes including the activation of inflammatory pathways, oxidative stress, and autophagy. Indeed, treatment with PCSK9i was able to counteract the IL-6 induced increase in inflammasome activation, the accrual of autophagic cells, and mitochondrial ROS accumulation. Of note, silencing of SIRT3 reverted the beneficial effects observed with PCSK9i treatment on all these phenomena. In atheroma specimens, the expression of PCSK9 was inversely related to that of SIRT3 while positively correlating with IL-6, IL-1β, and the ratio LC3B II/I. Conclusions: Overall, these data suggest that PCSK9i bear intrinsic anti-inflammatory, anti-autophagic, and antioxidant properties in endothelial cells, and that these pleiotropic effects might be mediated, at least in part, by SIRT3. These results provide an additional mechanism supporting the emerging knowledge relative to the benefit of PCSK9i on CVD beyond LDL-lowering and uncover SIRT3 as a putative mediator of such pleiotropy.

Pharmaco-invasive therapy: Early implementation of statins and proprotein convertase subtilisin/kexin type 9 inhibitors after acute coronary syndrome

Elevated LDL-cholesterol (LDL-C) plays a major role in atheroma formation and inflammation. Medical therapy to lower elevated LDL-C is the cornerstone for reducing the progression of atherosclerotic cardiovascular disease. Statin therapy, and more recently, other drugs such as proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, have proven efficacy in long-term lowering of LDL-C and therefore diminish cardiovascular risk. During an acute coronary syndrome (ACS), a systemic inflammatory response can destabilize other non-culprit atherosclerotic plaques. Patients with these vulnerable plaques are at high risk of experiencing recurrent cardiovascular events in the first few years post-ACS. Initiating intensive LDL-C lowering therapy in these patients with statins or PCSK9 inhibitors can be beneficial via several pathways. High-intensity statin therapy can reduce inflammation by directly lowering LDL-C, but also through its pleiotropic effects. PCSK9 inhibitors can directly lower LDL-C to recommended guideline thresholds, and could have additional effects on inflammation and plaque stability. We discuss the potential role of early implementation of statins combined with PCSK9 inhibitors to influence these cascades and to mediate the associated cardiovascular risk, over and above the well-known long-term beneficial effects of chronic LDL-C lowering.

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.

Reduction of C-reactive protein, low-density lipoprotein cholesterol, and its relationship with cardiovascular events of different lipid-lowering therapies: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

To evaluate the reductions of C-reactive protein (CRP) and low-density lipoprotein cholesterol (LDL-C) in different lipid-lowering drugs, and to assess the relationships between the reductions of CRP, LDL-C, and cardiovascular (CV) events.

METHODS

We searched MEDLINE, EMBASE, and Cochrane CENTRAL up to September 1, 2021. Randomized controlled trials (RCTs) comparing statins, proprotein convertase subtilisin/kexin type 9 monoclonal antibodies (PCSK9-mAbs), or ezetimibe against placebo with a treatment duration of at least 4 weeks and data on the effects of cholesterol-lowering interventions on LDL-C and CRP were included in this meta-analysis. The weighted mean difference (WMD) and 95% confidence interval (CI) were calculated.

RESULTS

Compared with placebo treatment, statins and ezetimibe treatments resulted in a significant decrease in LDL-C level (statins: WMD -47.94 mg/dL, 95% CI -51.21 to -44.67 mg/dL; ezetimibe: WMD -22.84 mg/dL, 95% CI -26.76 to -18.92 mg/dL) and CRP level (statins: WMD -0.67 mg/L, 95% CI -0.90 to -0.45 mg/dL; ezetimibe: -0.64 mg/L, 95% CI -1.07 to -0.21 mg/dL). Compared with placebo treatment, treatment with PCSK9-mAbs resulted in significant decrease in LDL-C level (WMD -54.24 mg/dL, 95% CI -59.77 to -48.70 mg/dL), while the concentration of CRP did not decrease significantly. Meta-regression analysis showed no significant association between change in CRP level and change in LDL-C level. Subgroup comparisons suggested that treatment with PCSK9-mAbs showed a greater reduction in LDL-C level when compared with the statins group and ezetimibe group, while the risks of CV death, myocardial infarction (MI), and stroke showed no significant differences.

CONCLUSION

Based on the current study, our results suggested that statins, ezetimibe, and PCSK9-mAbs are effective in reducing LDL-C levels. Treatment with statins and ezetimibe also demonstrated a significant effect on CRP. The traditional lipid-lowering strategy including statin and ezetimibe showed similar benefit on CV outcomes compared with the PCSK9-mAbs treatment.

Evolocumab on top of empagliflozin improves endothelial function of individuals with diabetes: randomized active-controlled trial

BACKGROUND

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) improve endothelial dysfunction and reduce cardiovascular events in individuals with type 2 diabetes (T2D). Proprotein convertase subtilisin/kexin 9 (PCSK9i) inhibitors reduce cardiovascular events in high-risk patients. Whether the addition of PCSK9i to SGLT2i treatment adds benefits is not known.

OBJECTIVES

To assess the PCSK9-i effect on the endothelial function of T2D individuals under treatment with SGLT2-i.

METHODS

Individuals with T2D were randomized in a 1:1 ratio to a 16-week treatment with either empagliflozin (E) or empagliflozin plus evolocumab (EE). The primary endpoint was post-treatment change from baseline in flow-mediated dilation (FMD) at 1-min. Secondary outcomes included changes in plasma levels of nitric oxide metabolites and isoprostane.

RESULTS

A total of 110 patients were enrolled, the mean age was 58 years, and 71% were men. The median post-treatment change in FMD at 1-min was 2.7% (interquartile range [IQR]: 0.9%) and 0.4% (IQR: 0.9%) in the EE and E groups, respectively (p < 0.001). There was a greater increase in plasma levels of nitrate [5.9 (16.5) vs. 2.6 (11.8); p = 0.001] and nitrite [0.14 (0.72) vs. 0.02 (0.74); p = 0.025] in the EE group than in the E group, respectively. Isoprostane reduction was more pronounced in the EE group when compared to the E group [-1.7 (5.9) vs. -1.1 (5.3); p < 0.001).

CONCLUSIONS

In individuals with T2D, the addition of evolocumab on top of empagliflozin improves endothelial function.

Effect of colchicine on inflammatory markers in patients with coronary artery disease: A meta-analysis of clinical trials

Whether colchicine reduces the levels of high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6) remains uncertain. Therefore, this systematic review and meta-analysis were conducted to evaluate the overall effect of colchicine treatment on hs-CRP and IL-6 levels in patients with coronary artery disease (CAD). PubMed/Medline, Embase, and the Cochrane Central Register of Controlled Trials were searched for studies published before October 2021. Clinical trials in patients with CAD with reports of hs-CRP and IL-6 level changes before and after colchicine intervention were included. In total, 11 trials on hs-CRP and two trials on IL-6 were included in this meta-analysis. Compared with that in the control group, colchicine treatment was significantly associated with decreased hs-CRP levels (weighted mean differences [WMDs], -0.81 mg/L; 95% confidence interval [CI], -1.34 to -0.28 mg/L; P = 0.003) in patients with CAD. Besides, the levels of IL-6 were significantly reduced in colchicine users compared to that of placebo (WMD, -1.28 pg/mL; 95% CI, -2.35 to -0.21 pg/mL; P = 0.02). In a subgroup analysis, colchicine led to a significant reduction in hs-CRP levels in studies with duration of intervention >7 days (WMD, -0.65 mg/L; 95% CI, -1.08 to -0.21 mg/L; P = 0.004) and studies with baseline hs-CRP levels ≥3.0 mg/L (WMD, -0.99 mg/L; 95% CI, -1.92 to -0.06 mg/L; P = 0.04). Colchicine intervention was associated with a reduction in hs-CRP and IL-6 levels in patients with CAD. Future investigations are required to verify the effect of colchicine on inflammatory markers and clarify the potential mechanisms of the cross talk between colchicine, inflammation, and cardiovascular outcomes.

Bempedoic acid in patients with type 2 diabetes mellitus, prediabetes, and normoglycaemia: A post hoc analysis of efficacy and glycaemic control using pooled data from phase 3 clinical trials

AIM

To evaluate the effect of bempedoic acid on glycaemic and lipid variables in patients with hypercholesterolaemia.

METHODS

A patient-level pooled analysis of four phase 3, randomized, double-blind, placebo-controlled trials evaluated changes in glycaemia, change from baseline in LDL-C, and adverse events. Patients (N = 3621) on maximally tolerated statins were randomized 2:1 to oral bempedoic acid 180 mg or placebo once daily for 12 to 52 weeks with the results analysed by baseline glycaemic status (diabetes, prediabetes, or normoglycaemia).

RESULTS

The annual rate of new-onset diabetes for bempedoic acid versus placebo in patients with normoglycaemia at baseline (n = 618) was 0.3% versus 0.8%, and for patients with prediabetes at baseline (n = 1868) it was 4.7% versus 5.9%. In patients with diabetes or prediabetes, bempedoic acid significantly (P < .0001) reduced HbA1c by -0.12% and -0.06%, respectively, and did not worsen fasting glucose versus placebo. Bempedoic acid significantly and consistently lowered LDL-C levels versus placebo, regardless of baseline glycaemic status (placebo-corrected difference range, -17.2% to -29.6%; P < .001 for each stratum). The safety of bempedoic acid was comparable with placebo and similar across glycaemic strata.

CONCLUSIONS

Bempedoic acid significantly lowered LDL-C across glycaemic strata and did not worsen glycaemic variables or increase the incidence of new-onset diabetes versus placebo over a median follow-up of 1 year.

Evidence for intensive LDL-C lowering for acute coronary syndrome: Recommendations from the Lipid Association of India

Patients with acute coronary syndrome (ACS) have a high risk of subsequent adverse cardiovascular outcomes, particularly within the first 30 days. Although it is well documented that initiation of statin therapy in the setting of ACS improves short- and long-term cardiovascular outcomes, and achievement of lower levels of low density lipoprotein cholesterol (LDL-C) incrementally improves outcomes, many patients with ACS have persistent hypercholesterolemia after discharge from the hospital. This is a missed opportunity that prompted the Lipid Association of India to develop recommendations for earlier initiation of more aggressive LDL-C lowering treatment, particularly for patients of South Asian descent who are well-documented to have earlier onset of more aggressive atherosclerotic cardiovascular disease. The Lipid Association of India recommends individualized aggressive LDL-C goals after ACS, which can be rapidly achieved with high intensity statin therapy and subsequent goal-directed adjunctive treatment with ezetimibe and PCSK9 inhibitors. Improved treatment of hypercholesterolemia achieved within weeks after ACS has the potential to reduce the high rate of morbidity and mortality in these high risk patients.

The Influence of Treatment with PCSK9 Inhibitors and Variants in the CRP (rs1800947), TNFA (rs1800629), and IL6 (rs1800795) Genes on the Corresponding Inflammatory Markers in Patients with Very High Lipoprotein(a) Levels

Chronic inflammation contributes significantly to the development and progression of atherosclerosis. However, the factors that lead to an inflammatory imbalance towards a proinflammatory state are not yet fully understood. The CRP rs1800947, TNFA rs1800629, and IL6 rs1800795 polymorphisms may play a role in the pathogenesis of atherosclerosis and were therefore selected to investigate the influence of genetic variability on the corresponding plasma levels after treatment with a proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor. A group of 69 patients with stable coronary artery disease after myocardial infarction before the age of 50 years and very high lipoprotein(a) levels were enrolled in the study. All patients received a PCSK9 inhibitor (evolocumab or alirocumab). Genotyping was performed using TaqMan assays (CRP rs1800947, TNFA rs1800629, and IL6 rs1800795). Consistent with previous studies, no significant change in levels of inflammatory biomarkers was observed after 6 months of treatment with PCSK9 inhibitors. We also did not detect any significant association between single nucleotide polymorphisms CRP rs1800947, TNFA rs1800629, and IL6 rs1800795 and plasma levels of high-sensitivity C-reactive protein (hsCRP), tumor necrosis factor-α (TNF-α), or interleukin 6 (IL6), respectively, at enrollment. However, the difference in IL6 levels after treatment with PCSK9 inhibitors was statistically significant (p = 0.050) in patients with IL6-74CC genotype, indicating the possible role of the IL6 rs1800795 polymorphism in modulating inflammation.

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.

Persistent inflammatory residual risk despite aggressive cholesterol-lowering therapy: what is next?

PURPOSE OF REVIEW

To briefly summarize recently published evidence on the possible therapeutic modulation of inflammatory processes in atherosclerotic cardiovascular disease (ASCVD), focusing on the rationale for an additional randomized clinical trial, targeting both persistently elevated cholesterol and inflammatory residual risk and critically discuss still open issues and future perspectives with regard to treatment allocation.

RECENT FINDINGS

Several large-scale clinical trials over the past few years have advanced our understanding of the role of inflammation in atherosclerosis, demonstrating that targeting the NLRP3 inflammasome and the IL-1β pathway indeed represent a new avenue to reduce residual risk in patients with ASCVD. However, despite optimal lipid-lowering therapy and novel options to modulate residual inflammatory risk, there are still a large number of individuals, being at high risk for recurrent ASCVD events.

SUMMARY

The integration of a dual target strategy aimed at lowering the inflammatory burden in combination with aggressive lipid-modifying for those at high/very high ASCVD risk may hold potential to significantly improve patient care. However, a number of questions related to the design of such 2 × 2 factorial trial still needs to be answered.

Effect of PCSK9 inhibitors on pulse wave velocity and monocyte-to-HDL-cholesterol ratio in familial hypercholesterolemia subjects: results from a single-lipid-unit real-life setting

AIMS

Subjects with familial hypercholesterolemia (FH) are characterized by an increased amount of low-density lipoprotein cholesterol (LDL-C) that promotes a continuous inflammatory stimulus. Our aim was to evaluate the effect of PCSK9-i on inflammatory biomarkers, neutrophil-to-lymphocyte ratio, monocyte-to-high-density lipoprotein ratio (MHR), and on early atherosclerosis damage analyzed by pulse wave velocity (PWV) in a cohort of FH subjects.

METHODS

In this prospective observational study, we evaluated 56 FH subjects on high-intensity statins plus ezetimibe and with an off-target LDL-C. All subjects were placed on PCSK9-i therapy and obtained biochemical analysis as well as PWV evaluation at baseline and after six months of PCSK9-i therapy.

RESULTS

After six months of add-on PCSK9-i therapy, only 42.9% of FH subjects attained LDL-C targets. As expected, a significant reduction of LDL-C (- 49.61%, p < 0.001) was observed after PCSK9-i therapy. Neutrophil count (NC) and MHR were reduced by PCSK9-i (-13.82% and -10.47%, respectively, p value for both < 0.05) and PWV significantly decreased after PCSK9-i therapy (- 20.4%, p < 0.05). Finally, simple regression analyses showed that ∆ PWV was significantly associated with ∆ LDL-C (p < 0.01), ∆ NC and ∆ MHR (p value for both < 0.05).

CONCLUSIONS

In conclusion, PCSK9-i therapy significantly improved lipid and inflammatory profiles and PWV values in FH subjects; our results support the positive effect of PCSK9-i in clinical practice.

Lipid lowering with bempedoic acid added to a proprotein convertase subtilisin/kexin type 9 inhibitor therapy: A randomized, controlled trial

BACKGROUND

Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9is) lower low-density lipoprotein cholesterol (LDL-C) in patients with hypercholesterolemia. However, some patients receiving PCSK9i therapy might require additional lipid-lowering therapy (LLT) to reach LDL-C goals. Bempedoic acid is an oral, once-daily, ATP-citrate lyase inhibitor that significantly lowers LDL-C in patients with hypercholesterolemia when given alone or as add-on therapy to statins and/or ezetimibe.

OBJECTIVE

Assess safety and efficacy of bempedoic acid added to PCSK9i (evolocumab) background therapy in patients with hypercholesterolemia.

METHODS

This phase 2, randomized, double-blind, placebo-controlled study was conducted in three phases: 1.5-month screening/washout period including discontinuation of all LLTs, a 3-month period wherein patients initiated background PCSK9i therapy, and a 2-month treatment period in which patients were randomized 1:1 to receive bempedoic acid 180 mg or placebo once daily while continuing PCSK9i therapy.

RESULTS

Of 59 patients randomized, 57 completed the study. Mean baseline LDL-C after 3 months of PCSK9i background therapy was 103.1 ± ± 30.4 mg/dL. Bempedoic acid added to background PCSK9i therapy significantly lowered LDL-C by 30.3% (P < .001) vs placebo. Compared with placebo, bempedoic acid significantly lowered apolipoprotein B, non-high-density lipoprotein cholesterol, and total cholesterol (nominal P < .001 for all), and high-sensitivity C-reactive protein (P = .029). When added to background PCSK9i therapy, the safety profile of bempedoic acid was comparable to that observed for placebo.

CONCLUSIONS

When added to a background of PCSK9i therapy, bempedoic acid significantly lowered LDL-C levels with a safety profile comparable to placebo in patients with hypercholesterolemia.

Pcsk9 Knockout Aggravated Experimental Apical Periodontitis via LDLR

Apical periodontitis (AP), an inflammatory lesion around the apex of tooth roots, is mostly caused by dental pulp infection. Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a vital role in regulating cholesterol homeostasis by targeting low-density lipoprotein receptor (LDLR) and participates in bacterium-induced chronic periodontitis. However, the roles of PCSK9 in AP are unknown. Here, we investigated its role in AP by using Pcsk9^-/- mice. Micro-computed tomography scanning and histological staining revealed that the periapical bone loss of Pcsk9^-/- mice was greater than that of wild-type (WT) mice, and increased expression of inflammation-related factors tumor necrosis factor α (TNF-α) and interleukin (IL)-6 was also observed. Immunofluorescence staining and quantitative real-time polymerase chain reaction showed PCSK9 expression in bone marrow macrophages (BMMs) was increased after treatment with lipopolysaccharide (LPS). This finding was consistent with the in vivo results that the expression level of PCSK9 in exposed WT mice increased compared with that in unexposed WT mice. After LPS challenge, the expression levels of TNF-α, IL-1β, and IL-6 in BMMs were increased, and Pcsk9 knockout aggravated the expression of these inflammatory factors. The number of osteoclasts positive for tartrate-resistant acid phosphatase staining around the apical lesion in Pcsk9^-/- mice was higher than that in WT mice. Then BMMs underwent the osteoclast differentiation. Pcsk9 knockout BMMs induced increased and larger osteoclasts. While this effect of Pcsk9 knockout was abolished by the addition of Ldlr small interfering RNA, revealing that Pcsk9 knockout increased osteoclastogenesis was dependent on the LDLR. Immunohistochemistry staining showed increased expression level of LDLR in exposed Pcsk9^-/- periapical areas. In vitro experiments showed that LPS promoted the expression level of LDLR in Pcsk9^-/- BMMs and increased osteoclast formation ability, indicating that LPS promoted the elevation of osteoclasteogenesis caused by the Pcsk9 knockout. In conclusion, Pcsk9 deficiency aggravated the inflammatory response and promoted the osteoclastogenesis in an LDLR-dependent manner in AP experimental mice.

Inflammation and Cardiovascular Disease: The Future

Despite considerable advances in reducing the global burden of atherosclerotic cardiovascular disease by targeting conventional risk factors, significant residual risk remains, with low-grade inflammation being one of the strongest risk modifiers. Inflammatory processes within the arterial wall or systemic circulation, which are driven in a large part by modified lipoproteins but subsequently trigger a hypercoagulable state, are a hallmark of atherosclerotic cardiovascular disease and, in particular, its clinical complications. Extending conventional guideline-based clinical risk stratification algorithms by adding biomarkers of inflammation may refine phenotypic screening, improve risk stratification and guide treatment eligibility in cardiovascular disease prevention. The integration of interventions aimed at lowering the inflammatory burden, alone or in combination with aggressive lipid-modifying or even antithrombotic agents, for those at high cardiovascular risk may hold the potential to reduce the still substantial burden of cardiometabolic disease. This review provides perspectives on future clinical research in atherosclerosis addressing the tight interplay between inflammation, lipid metabolism and thrombosis, and its translation into clinical practice.

PCSK9 inhibition, LDL and lipopolysaccharides: a complex and "dangerous" relationship

Literature concerning the causative factors of atherosclerotic cardiovascular disease shows complex and sometimes contrasting evidence. Most guidelines suggest a strategy aimed at lowering circulating low density lipoproteins (LDL) and ApoB lipoprotein levels. The use of statins and of cholesteryl ester transfer protein inhibitors has led to a number of controversial outcomes, generating a certain degree of concern about the real efficacy and especially safety of these drugs. Literature data show that the use of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors results in a dramatic reduction of various markers of lipid metabolism (namely LDL); however, several critical scientific papers have questioned the value, the need and especially the safety of these innovative drugs. LDL are a protective factor against lipopolysaccharides and other microbial derivatives. Similarly, these gram-negative bacteria-derived compounds have been identified as probable culprits of cardiovascular atherogenesis; moreover, lipopolysaccharides increase hepatic synthesis of PCSK9, as defense mechanism. This enzyme modulates LDL receptors level in the liver, as well as in other organs, such as adrenal gland and reproductive organs. Hence, PCSK9 inhibition may influence glucocorticoid secretion and fertility. Lastly, the consequent reduction of circulating LDL may relevantly hindrance immune system and favor lipopolysaccharides diffusion.

Familial hypercholesterolaemia and COVID-19: A two-hit scenario for endothelial dysfunction amenable to treatment

Patients with familial hypercholesterolemia (FH) are likely at increased risk for COVID-19 complications in the acute phase of the infection, and for a long time thereafter. Because in FH patients the level of low density lipoprotein cholesterol (LDL-C) is elevated from birth and it correlates with the degree of systemic endothelial dysfunction, both heterozygous FH (HeFH) patients and, in particular, homozygous FH (HoFH) patients have a dysfunctional endothelium prone to further damage by the direct viral attack and the hyper-inflammatory reaction typical of severe COVID-19. Evidence to date shows the benefit of statin use in patients with COVID-19. In FH patients, the focus should therefore be on the effective lowering of LDL-C levels, the root cause of the expected excess vulnerability to COVID-19 infection in these patients. Moreover, the ongoing use of statins and other lipid-lowering therapies should be encouraged during the COVID pandemic to mitigate the risk of cardiovascular complications from COVID-19. For the reduction of the excess risk in FH patients with COVID-19, we advocate stringent adherence to the guideline determined LDL-C levels for FH patients, or maybe even to lower levels. Unfortunately, epidemiologic data are lacking on the severity of COVID-19 infections, as well as the number of acute cardiac events that have occurred in FH subjects during the COVID-19 pandemic. Such data need to be urgently gathered to learn how much the risk for, and the severity of COVID-19 in FH are increased.

Recent efforts in drug discovery on vascular inflammation and consequent atherosclerosis

Introduction: Preservation of vascular endothelium integrity and maintenance of its full functionality are fundamental aspects in order to avoid both cardiovascular and non-cardiovascular diseases.Areas covered: Although a massive endothelial disruption is a rare condition, caused by acute and uncontrolled inflammatory responses (e.g. the cytokine storm induced by SARS-CoV-2 infection), more frequently the vascular tree is the first target of slowly progressive inflammatory processes which affect the integrity of endothelium and its 'barrier' function, supporting the onset of atherosclerotic plaque and spreading inflammation. This endothelial dysfunction leads to decrease NO biosynthesis, impaired regulation of vascular tone, and increased platelet aggregation. Such chronic subclinic inflammation leads to macrophage infiltration in atherosclerotic lesions. Therefore, many efforts should be addressed to find useful approaches to preserve vascular endothelium from inflammation. In this review, the authors have evaluated the most recent strategies to counteract this pathological condition.Expert opinion: The therapeutic and nutraceutical approaches represent useful tools to treat or prevent different phases of vascular inflammation. In particular, the pharmacological approach should be used in advanced phases characterized by clinical signs of vascular disease, whilst the nutraceutical approach may represent a promising preventive strategy to preserve the integrity of the endothelial tissue.

PCSK9 regulates pyroptosis via mtDNA damage in chronic myocardial ischemia

Proprotein convertase subtilisin/Kexin type 9 (PCSK9) and pyroptosis both play important roles in myocardial infarction. This study was designed to test the hypothesis that PCSK9 regulates pyroptosis in cardiomyocytes during chronic myocardial ischemia. Primary cardiomyocytes were isolated from WT and PCSK9^-/- mice. HL-1 cardiomyocytes were used to set up PCSK9-deficient (PCSK9^-/-) and PCSK9-upregulated (PCSK9^CRISPRa) cardiomyocyte cell line with CRISPR/Cas9 knockout or activation plasmid. Additional studies were performed with chronic myocardial ischemia in WT and PCSK9^-/- mice. We observed that PCSK9 initiates mitochondrial DNA (mtDNA) damage, activates NLRP3 inflammasome signaling (NLRP3, ASC, Caspase-1, IL-1β, and IL-18), and subsequently induces Caspase-1-dependent pyroptosis. There was an intense expression of PCSK9 and pyroptosis marker, GSDMD-NT, in the zone bordering the infarct area. PCSK9^-/- significantly suppressed expression of NLRP3 inflammasome signaling, GSDMD-NT, and LDH release. Furthermore, serum levels of PCSK9, NLPR3 inflammasome signaling, and pyroptosis (GSDMD and LDH release) were significantly elevated in patients with chronic myocardial ischemia as compared to those in age-matched healthy subjects. Human hearts with recent infarcts also showed high expression of PCSK9 and GSDMD-NT in the border zone similar to that in the infarcted mouse heart. These observations provide compelling evidence for the role of PCSK9 in regulating Caspase-1-dependent pyroptosis via mtDNA damage and may qualify pro-inflammatory cytokines and pyroptosis as potential targets to treat PCSK9-related cardiovascular diseases.

Statins and C-reactive protein: in silico evidence on direct interaction

INTRODUCTION

Statins are known to lower CRP, and this reduction has been suggested to contribute to the established efficacy of these drugs in reducing cardiovascular events and outcomes. However, the exact mechanism underlying the CRP-lowering effect of statins remains elusive.

METHODS

In order to test the possibility of direct interaction, we performed an in silico study by testing the orientation of the respective ligands (statins) and phosphorylcholine (the standard ligand of CRP) in the CRP active site using Molecular Operating Environment (MOE) software.

RESULTS

Docking experiments showed that all statins could directly interact with CRP. Among statins, rosuvastatin had the strongest interaction with CRP (pKi = 16.14), followed by fluvastatin (pKi = 15.58), pitavastatin (pKi = 15.26), atorvastatin (pKi = 14.68), pravastatin (pKi = 13.95), simvastatin (pKi = 7.98) and lovastatin (pKi = 7.10). According to the above-mentioned results, rosuvastatin, fluvastatin, pitavastatin and atorvastatin were found to have stronger binding to CRP compared with the standard ligand phosphocholine (pKi = 14.55).

CONCLUSIONS

This finding suggests a new mechanism of interaction between statins and CRP that could be independent of the putative cholesterol-lowering activity of statins.

Evolocumab, a PCSK9-Monoclonal Antibody, Rapidly Reverses Coronary Artery Endothelial Dysfunction in People Living With HIV and People With Dyslipidemia

Background PCSK9 (proprotein convertase subtilisin/kexin type 9) is well recognized for its important role in cholesterol metabolism. Elevated levels are associated with increased cardiovascular risk and inhibition with PCSK9 antibodies (PCSK9i) lowers cardiovascular events in patients with coronary artery disease. PCSK9 levels are also elevated in people living with HIV (PLWH) and those with dyslipidemia. Because increased PCSK9 in PLWH is associated with impaired coronary endothelial function, a barometer of coronary vascular health, we tested the hypothesis that PCSK9i improves impaired coronary endothelial function in dyslipidemia without coronary artery disease and in PLWH with nearly optimal/above goal low-density lipoprotein cholesterol levels. Methods and Results We performed a single-center study in 19 PLWH and 11 with dyslipidemia to evaluate the effects of the PCSK9i evolocumab on coronary endothelial function using cine 3T MRI to noninvasively measure coronary endothelial function, assessed as the changes in coronary cross-sectional area and coronary blood flow from rest to that during isometric handgrip exercise, a known endothelial-dependent vasodilator. Before evolocumab, there was a decrease or no coronary vasodilation and no increase in coronary blood flow (the normal responses) to isometric handgrip exercise in either group. Following 6 weeks of evolocumab, 480 mg q4 weeks, the % cross-sectional area changes from rest to isometric handgrip exercise were +5.6±5.5% and +4.5±3.1% in the PLWH and dyslipidemia groups, respectively, both P<0.01 versus baseline. Improved cross-sectional area was paralleled by a significant coronary blood flow improvement in both groups. Conclusions To our knowledge, these data represent the first evidence that PCSK9 inhibition improves coronary artery health in PLWH and people with dyslipidemia. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03500302.

Efficacy and Safety of Bempedoic Acid in Patients With Hypercholesterolemia and Statin Intolerance

Background

Inability to tolerate statins because of muscle symptoms contributes to uncontrolled cholesterol levels and insufficient cardiovascular risk reduction. Bempedoic acid, a prodrug that is activated by a hepatic enzyme not present in skeletal muscle, inhibits ATP‐citrate lyase, an enzyme upstream of β‐hydroxy β‐methylglutaryl‐coenzyme A reductase in the cholesterol biosynthesis pathway.

Methods and Results

The phase 3, double‐blind, placebo‐controlled CLEAR (Cholesterol Lowering via Bempedoic acid, an ACL‐Inhibiting Regimen) Serenity study randomized 345 patients with hypercholesterolemia and a history of intolerance to at least 2 statins (1 at the lowest available dose) 2:1 to bempedoic acid 180 mg or placebo once daily for 24 weeks. The primary end point was mean percent change from baseline to week 12 in low‐density lipoprotein cholesterol. The mean age was 65.2 years, mean baseline low‐density lipoprotein cholesterol was 157.6 mg/dL, and 93% of patients reported a history of statin‐associated muscle symptoms. Bempedoic acid treatment significantly reduced low‐density lipoprotein cholesterol from baseline to week 12 (placebo‐corrected difference, −21.4% [95% CI, −25.1% to −17.7%]; P<0.001). Significant reductions with bempedoic acid versus placebo were also observed in non–high‐density lipoprotein cholesterol (−17.9%), total cholesterol (−14.8%), apolipoprotein B (−15.0%), and high‐sensitivity C‐reactive protein (−24.3%; P<0.001 for all comparisons). Bempedoic acid was safe and well tolerated. The most common muscle‐related adverse event, myalgia, occurred in 4.7% and 7.2% of patients who received bempedoic acid or placebo, respectively.

Conclusions

Bempedoic acid offers a safe and effective oral therapeutic option for lipid lowering in patients who cannot tolerate statins.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov. Unique identifier: NCT02988115.

See Editorial by Jia and Virani

Role of non-statin lipid-lowering therapy in coronary atherosclerosis regression: a meta-analysis and meta-regression

BACKGROUND

Several studies have investigated the association between non-statin lipid-lowering therapy and regression of atherosclerosis. However, these studies were mostly small and their results were not always robust. The objectives were: (1) to define if a dual lipid-lowering therapy (statin + non-statin drugs) is associated with coronary atherosclerosis regression, estimated by intravascular ultrasound (IVUS); (2) to assess the association between dual lipid-lowering-induced changes in low density lipoprotein cholesterol (LDL-C) and non-high-density-lipoprotein cholesterol (non-HDL-C) levels and atherosclerosis regression.

METHODS

A meta-analysis including trials of non-statin lipid-lowering therapy, reporting LDL-C, non-HDL-C and total atheroma volume (TAV) with a minimum of 6 months of follow-up was performed. The primary endpoint was defined as the change in TAV measured from baseline to follow-up, comparing groups of subjects on statins alone versus combination of statin and non-statin drugs. The random-effects model and meta-regression were performed.

RESULTS

Eight eligible trials of non-statin lipid-lowering drugs (1759 patients) were included. Overall, the dual lipid-lowering therapy was associated with a significant reduction in TAV [- 4.0 mm3 (CI 95% -5.4 to - 2.6)]; I2 = 0%]. The findings were similar in the stratified analysis according to the lipid-lowering drug class (ezetimibe or PCSK9 inhibitors). In the meta-regression, a 10% decrease in LDL-C or non-HDL-C levels, was associated, respectively, with 1.0 mm3 and 1.1 mm3 regressions in TAV.

CONCLUSION

These data suggests the addition of ezetimibe or PCSK9 inhibitors to statin therapy results in a significant regression of TAV. Reduction of coronary atherosclerosis observed with non-statin lipid-lowering therapy is associated to the degree of LDL-C and non-HDL-C lowering. Therefore, it seems reasonable to achieve lipid goals according to cardiovascular risk and regardless of the lipid-lowering strategy used (statin monotherapy or dual treatment).

The Pleiotropic Effects of Statins - From Coronary Artery Disease and Stroke to Atrial Fibrillation and Ventricular Tachyarrhythmia

Statins, 3-hydroxy-methylglutaryl coenzyme A reductase inhibitors, have been used for decades for the prevention of coronary artery disease and stroke. They act primarily by lowering serum cholesterol through the inhibition of cholesterol synthesis in the liver, which results in the upregulation of low-density lipoprotein receptors in the liver. This results in the removal of low-density lipoproteincholesterol. Studies have suggested that statins may demonstrate additional effects that are independent of their effects on low-density lipoprotein-cholesterol. These have been termed "pleiotropic" effects. Pleiotropic effects may be due to the inhibition of isoprenoid intermediates by statins. Isoprenoid inhibition has effects on the small guanosine triphosphate binding proteins Rac and Rho which in turn effects nicotinamide adenine dinucleotide phosphate oxidases. Therefore, there are changes in endothelial nitric oxide synthase expression, atherosclerotic plaque stability, pro-inflammatory cytokines and reactive oxygen species production, platelet reactivity, and cardiac fibrosis and hypetrophy development. Recently, statins have been compared to the ezetimibe and the recently published outcomes data on the proprotein convertase subtilisin kexin type 9 inhibitors has allowed for a reexamination of statin pleiotropy. As a result of these diverse effects, it has been suggested that statins also have anti-arrhythmic effects. This review focuses on the mechanisms of statin pleiotropy and discusses evidence from the statin clinical trials as well as examining the possible anti-arrhythmic effects atrial fibrillation and ventricular tachyarrhythmias.

Residual inflammatory risk after contemporary lipid lowering therapy

BACKGROUND

Recently, there has been an increasing interest in targeting inflammation to reduce major adverse cardiovascular events (MACE) in patients with cardiovascular risk. Statins, PCSK9 inhibitors, and ezetimibe have been shown to reduce MACE owing to reduction in low-density lipoproteins cholesterol (LDL-c). Herein, we investigate whether the intensity of these agents is associated with (i) discernible reduction in inflammation measured by the levels of high-sensitivity C-reactive protein (hsCRP); (ii) reduction in MACE; (iii) if there is an association between the baseline hsCRP and MACE.

METHODS AND RESULTS

Electronic databases were searched for randomized controlled trials (RCTs) that compared statins, ezetimibe, PCSK9 inhibitors with placebos/active controls and reported MACEs and hsCRP (mg/L). Studies were stratified based on baseline hsCRP (<2, 2-3, >3) with subgroup analysis conducted across each stratum. Fourteen RCTs including 133 109 patients randomized into more intensive therapy (MIT) and less intensive therapy were selected. Meta-analysis did not demonstrate any significant differences between use of MIT and hsCRP levels (mean difference, -0.02; CI, -0.06, 0.02; P = 0.31). The MIT significantly reduced the risk of MACE (RR, 0.82; CI, 0.75, 0.91; P < 0.001). The relative risk and absolute risk remained consistent across the strata. However, there was a 0.5% statistically significant absolute risk reduction in all-cause mortality in patients with higher hsCRP (RD, -0.005; CI, -0.009, -0.001; P = 0.01).

CONCLUSION

Overall, LDL-c lowering therapies reduce relative risk of MACEs particularly in patients with higher baseline hsCRP. However, there appears to be a residual inflammatory risk despite the use of contemporary lipid lowering agents.

Research progress on alternative non-classical mechanisms of PCSK9 in atherosclerosis in patients with and without diabetes

The proprotein convertase subtilisin/kexin type 9 (PCSK9) acts via a canonical pathway to regulate circulating low-density lipoprotein-cholesterol (LDL-C) via degradation of the LDL receptor (LDLR) on the liver cell surface. Published research has shown that PCSK9 is involved in atherosclerosis via a variety of non-classical mechanisms that involve lysosomal, inflammatory, apoptotic, mitochondrial, and immune pathways. In this review paper, we summarized these additional mechanisms and described how anti-PCSK9 therapy exerts effects through these mechanisms. These additional pathways further illustrate the regulatory role of PCSK9 in atherosclerosis and offer an in-depth interpretation of how the PCSK9 inhibitor exerts effects on the treatment of atherosclerosis.

Proposed low-density lipoprotein cholesterol goals for secondary prevention and familial hypercholesterolemia in India with focus on PCSK9 inhibitor monoclonal antibodies: Expert consensus statement from Lipid Association of India

BACKGROUND

Rates of atherosclerotic cardiovascular disease (ASCVD) are strikingly high in India compared to Western countries and are increasing. Moreover, ASCVD events occur at a younger age with only modest hypercholesterolemia, most commonly with low levels of high-density lipoprotein cholesterol. The course of ASCVD also appears to be more fulminant with higher mortality.

OBJECTIVE

In light of these issues, the Lipid Association of India (LAI) endeavored to develop revised guidelines with more aggressive low-density lipoprotein cholesterol (LDL-C) goals in secondary prevention and for patients with familial hypercholesterolemia compared to guidelines in the United States and other countries.

METHODS

Owing to the paucity of clinical outcomes data in India, it was necessary to place major emphasis on expert opinion as a complement to randomized placebo-controlled data generated mostly in non-Indian cohorts. To facilitate this process, the LAI conducted a series of 19 meetings among 162 lipid specialists in 13 cities throughout India over a period of 11 months before formulating this expert consensus statement.

RESULTS

The LAI recommends an LDL-C goal <50 mg/dL in all patients in secondary prevention or very high-risk primary prevention but proposes an optional goal ≤30 mg/dL in category A extreme-risk patients (eg, coronary artery disease + familial hypercholesterolemia) and a recommended goal ≤30 mg/dL in category B extreme-risk patients [coronary artery disease + (1) diabetes and polyvascular disease/≥3 major ASCVD risk factors/end organ damage, or (2) recurrent acute coronary syndrome within 12 months despite LDL-C <50 mg/dL, or (3) homozygous familial hypercholesterolemia].

CONCLUSIONS

More aggressive LDL-C goals are needed for prevention of ASCVD in India, as described in this expert consensus statement. Use of statins and ezetimibe needs to increase in India in combination with improved control of other ASCVD risk factors. Proprotein convertase subtilisin kexin type 9 inhibitors can improve LDL-C goal achievement in patients with refractory hypercholesterolemia.