Antisense oligonucleotides targeting apolipoprotein(a) in people with raised lipoprotein(a): two randomised, double-blind, placebo-controlled, dose-ranging trials

Lipoprotein (a) testing patterns among subjects with a measured lipid panel: The Mayo Clinic experience

Objective

Lipoprotein(a) [Lp(a)] has been associated with Atherosclerotic Cardiovascular Disease (ASCVD). Approximately 20 % of the population has elevated Lp(a). Despite its well-recognized role in ASCVD, universal screening remains controversial. The aim of our study is to investigate laboratory testing patterns for Lp(a) in subjects screened with a standard lipid panel at a large tertiary referring US institution.

Methods

Data were retrospectively collected at Mayo Clinic from the Mayo Data Explorer (MDE). Subjects were included if they had a lipid panel measured between May 1, 2022, and April 30, 2023. Demographic data, Lp(a) measurements, statins and aspirin prescription and ASCVD events which occurred at any time in the life of a subject were recorded along with respective dates. The cumulative number of Lp(a) laboratory test orders were also tallied from 1994 to 2023 independently of the lipid panel requests.

Results

Between May 1, 2022, and April 30, 2023, 257,225 subjects had a lipid panel ordered. Of these, only 386 (0.15 %) had Lp(a) tested within 1 year of the lipid panel, while 2406 (0.94 %) had Lp(a) tested at any time. Lp(a) was tested more frequently in males (67 %) and in subjects who developed Myocardial Infarction (MI) at any time (12 %). Following Lp(a) results, there was no significant change in statin or aspirin prescription associated with Lp(a) levels. Secondary prevention was the main setting for ordering Lp(a) testing, and there was no change in this trend throughout the years.

Conclusions

Testing rates for Lp(a) in the general population are low and the main setting remains secondary prevention. Women are less tested than men. When Lp(a) is found to be elevated, often times there is no change in patient management to mitigate the ASCVD risk.

Association Between Lipoprotein(a) and Obstructive Coronary Artery Disease and High-Risk Plaque: Insights From the PROMISE Trial

The role of lipoprotein (a) (Lp[a]) in the development of obstructive coronary artery disease (CAD) and high-risk plaque (HRP) in primary prevention patients with stable chest pain is unknown. We sought to evaluate the relation of Lp(a), independent of low-density lipoprotein cholesterol (LDL-C), with the presence of obstructive CAD and HRP to improve understanding of the residual risk imparted by Lp(a) on CAD. We performed a secondary analysis in Prospective Multicenter Imaging Study for Evaluation of Chest Pain (PROMISE) Trial participants who had coronary computed tomographic angiography (CTA) performed and Lp(a) data available. Lp(a) concentration was analyzed as a binary variable, with elevated Lp(a) defined as ≥50 mg/100 ml. "Stenosis ≥50%" was defined as ≥50% coronary artery stenosis in any epicardial vessel, and "stenosis ≥70%" was defined as ≥70% coronary artery stenosis in any epicardial vessel and/or ≥50% left main coronary artery stenosis. HRP was defined as presence of plaque on CTA imaging with evidence of positive remodeling, low computed tomography attenuation, or napkin-ring sign. Multivariate logistic regression models were constructed to evaluate the association between Lp(a) and the outcomes of obstructive CAD and HRP stratified by LDL-C ≥100 versus <100 mg/100 ml. Of the 1,815 patients who underwent CTA and had Lp(a) data available, those with elevated Lp(a) were more commonly women and Black than those with lower Lp(a). Elevated Lp(a) was associated with stenosis ≥50% (odds ratio 1.57, 95% confidence interval 1.14 to 2.15, p = 0.005) and stenosis ≥70% (odds ratio 2.05, 95% confidence interval 1.34 to 3.11, p = 0.0008) in the multivariate models, and this relation was not modified by LDL-C ≥100 versus <100 mg/100 ml (interaction p >0.4). Elevated Lp(a) was not associated with HRP when adjusted for obstructive CAD. This study of patients without known CAD found that elevated Lp(a) ≥50 mg/100 ml was independently associated with the presence of obstructive CAD regardless of controlled versus uncontrolled LDL-C but was not independently associated with HRP when stenosis ≥50% or ≥70% was accounted for. Further research is warranted to delineate the role of Lp(a) in the residual risk for atherosclerotic cardiovascular disease that patients may have despite optimal LDL-C lowering.

Inflammatory and Lipid Biomarkers in Early Atherosclerosis: A Comprehensive Analysis

INTRODUCTION

Atherosclerosis is a leading cause of cardiovascular disease, characterized by lipid accumulation and chronic inflammation within arterial walls. Early detection in young adults is crucial for preventing adverse cardiovascular events. This study investigates the associations between inflammatory indices, lipid biomarkers, and the presence of atherosclerosis in patients aged 18 to 55 years.

METHODS

A cross-sectional study was conducted involving 89 participants divided into two groups: 62 patients with documented atherosclerosis (main group) and 27 healthy controls without significant atherosclerosis. Comprehensive data-including demographic information, medication use, imaging results, laboratory parameters, and calculated inflammatory indices (SIRI, SII, AISI, NLR, PLR, MLR)-were collected. Statistical analyses included correlation assessments, group comparisons using the Mann-Whitney U test, logistic regression modeling, feature importance analysis with Random Forest and Gradient Boosting classifiers, receiver operating characteristic (ROC) curves, and K-means clustering.

RESULTS

Significant differences were observed between the main and control groups. Patients with atherosclerosis exhibited elevated inflammatory indices (SIRI, NLR, MLR, SII) and lipid profile abnormalities (higher TC and LDL-C, lower HDL-C). Lp(a) and ANGPTL3 levels were significantly higher in the main group (p < 0.001 and p < 0.01, respectively). Logistic regression identified SIRI and ANGPTL3 as significant predictors of atherosclerosis, with the model demonstrating high accuracy (77%) and sensitivity (93%). Feature importance analysis confirmed the significance of SIRI and ANGPTL3, alongside traditional lipid biomarkers, in predicting disease presence. ROC analysis showed excellent model performance (AUC > 0.80). Clustering analysis revealed two distinct patient subgroups characterized by predominant inflammatory profiles or lipid metabolism disturbances.

CONCLUSIONS

Systemic inflammation and lipid abnormalities play significant roles in early atherosclerosis among young adults. Elevated SIRI and ANGPTL3 levels are potent predictors of disease presence. The integration of inflammatory indices and lipid biomarkers into predictive models enhances risk stratification and supports personalized medicine approaches.

Lipoprotein(a) in atherosclerotic cardiovascular disease and proprotein convertase subtilisin/kexin-type 9 inhibitors

High plasma lipoprotein(a) (Lp(a)) levels increase the cardiovascular risk in populations with atherosclerotic cardiovascular disease (ASCVD). Apolipoprotein (a) [apo(a)], a unique protein component of Lp(a), plays an important role in the pathogenesis of atherosclerosis. Statins, the primary medication in managing ASCVD, lower low-density lipoprotein cholesterol (LDL-C) but concurrently elevate plasma Lp(a) levels, contributing to an increased residual cardiovascular risk. In turn, proprotein convertase subtilisin/kexin-type 9 (PCSK9) inhibitors, a novel class of LDL-C lowering drugs, effectively reduce plasma Lp(a) levels, which is believed to decrease residual cardiovascular risk. However, the mechanism by which PCSK9 inhibitors reduce Lp(a) levels remains unknown. In addition, there are some clinical limitations of PCSK9 inhibitors. Here, we systematically review the past, present, and prospects of studies pertaining to Lp(a), PCSK9 inhibitors, and ASCVD.

Oxidised phosphatidylcholine induces sarcolemmal ceramide accumulation and insulin resistance in skeletal muscle

AIMS/HYPOTHESIS

Intracellular ceramide accumulation in specific cellular compartments is a potential mechanism explaining muscle insulin resistance in the pathogenesis of type 2 diabetes. Muscle sarcolemmal ceramide accumulation negatively impacts insulin sensitivity in humans, but the mechanism explaining this localised accumulation is unknown. Previous reports revealed that circulating oxidised LDL is elevated in serum of individuals with obesity and type 2 diabetes. Oxidised phosphatidylcholine, which is present in oxidised LDL, has previously been linked to ceramide pathway activation, and could contribute to localised ceramide accumulation in skeletal muscle. We hypothesised that oxidised phosphatidylcholine inversely correlates with insulin sensitivity in serum, and induces sarcolemmal ceramide accumulation and decreases insulin sensitivity in muscle.

METHODS

We used LC-MS/MS to quantify specific oxidised phosphatidylcholine species in serum from a cross-sectional study of 58 well-characterised individuals spanning the physiological range of insulin sensitivity. We also performed in vitro experiments in rat L6 myotubes interrogating the role of specific oxidised phosphatidylcholine species in promoting sarcolemmal ceramide accumulation, inflammation and insulin resistance in skeletal muscle cells.

RESULTS

Human serum oxidised phosphatidylcholine levels are elevated in individuals with obesity and type 2 diabetes, inversely correlated with insulin sensitivity, and positively correlated with sarcolemmal C18:0 ceramide levels in skeletal muscle. Specific oxidised phosphatidylcholine species, particularly 1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine (POVPC), increase total ceramide and dihydroceramide and decrease total sphingomyelin in the sarcolemma of L6 myotubes by de novo ceramide synthesis and sphingomyelinase activation. POVPC also increases inflammatory signalling and causes insulin resistance in L6 myotubes.

CONCLUSIONS/INTERPRETATION

These data suggest that circulating oxidised phosphatidylcholine species promote ceramide accumulation and decrease insulin sensitivity in muscle, help explain localised sphingolipid accumulation and muscle inflammatory response, and highlight oxidised phosphatidylcholine species as potential targets to combat insulin resistance.

Rational design of base, sugar and backbone modifications improves ADAR-mediated RNA editing

AIMers are short, chemically modified oligonucleotides that induce A-to-I RNA editing through interaction with endogenous adenosine deaminases acting on RNA (ADAR) enzymes. Here, we describe the development of new AIMer designs with base, sugar and backbone modifications that improve RNA editing efficiency over our previous design. AIMers incorporating a novel pattern of backbone and 2' sugar modifications support enhanced editing efficiency across multiple sequences. Further efficiency gains were achieved through incorporation of an N-3-uridine (N3U), in place of cytidine (C), in the 'orphan base' position opposite the edit site. Molecular modeling suggests that N3U might enhance ADAR catalytic activity by stabilizing the AIMer-ADAR interaction and potentially reducing the energy required to flip the target base into the active site. Supporting this hypothesis, AIMers containing N3U consistently enhanced RNA editing over those containing C across multiple target sequences and multiple nearest neighbor sequence combinations. AIMers combining N3U and the novel pattern of 2' sugar chemistry and backbone modifications improved RNA editing both in vitro and in vivo. We provide detailed N3U synthesis methods and, for the first time, explore the impact of N3U and its analogs on ADAR-mediated RNA editing efficiency and targetable sequence space.

New insights into the therapeutic options to lower lipoprotein(a)

BACKGROUND

Elevated levels of lipoprotein(a) [Lp(a)] represent a risk factor for cardiovascular disease including aortic valve stenosis, myocardial infarction and stroke. While the patho-physiological mechanisms linking Lp(a) with atherosclerosis are not fully understood, from genetic studies that lower Lp(a) levels protect from CVD independently of other risk factors including lipids and lipoproteins. Hereby, Lp(a) has been considered an appealing pharmacological target.

RESULTS

However, approved lipid lowering therapies such as statins, ezetimibe or PCSK9 inhibitors have a neutral to modest effect on Lp(a) levels, thus prompting the development of new strategies selectively targeting Lp(a). These include antisense oligonucleotides and small interfering RNAs (siRNAs) directed towards apolipoprotein(a) [Apo(a)], which are in advanced phase of clinical development. More recently, additional approaches including inhibitors of Apo(a) and gene editing approaches via CRISPR-Cas9 technology entered early clinical development.

CONCLUSION

If the results from the cardiovascular outcome trials, designed to demonstrate whether the reduction of Lp(a) of more than 80% as observed with pelacarsen, olpasiran or lepodisiran translates into the decrease of cardiovascular mortality and major adverse cardiovascular events, will be positive, lowering Lp(a) will become a new additional target in the management of patients with elevated cardiovascular risk.

Management of dyslipidemia in coronary artery disease: the present and the future

Coronary artery disease (CAD) remains a leading cause of global morbidity and mortality, necessitating continuous refinement in the management of dyslipidemia, one of its major risk factors, to mitigate cardiovascular risks. Previous studies have proven the critical role of immediate and robust low-density lipoprotein cholesterol (LDL-C) reduction in the aftermath of acute coronary syndrome (ACS). Emphasizing the evidence supporting this approach, we delve into the impact of early intervention on cardiovascular outcomes and propose optimal strategies for achieving rapid LDL-C lowering, while also providing the rationale for early proprotein convertase subtilisin/kexin 9 inhibitor use after an ACS. Given the importance of the residual lipidemic risk, we present an overview of emerging therapeutic avenues poised to reshape dyslipidemia management, such as bempedoic acid, lipoprotein(a) inhibition, ApoC3 modulation, and angiopoietin-like protein 3 targeting. This comprehensive review amalgamates current evidence with future prospects, offering a holistic perspective on the management of dyslipidemia in CAD. By exploring both the urgency for immediate post-ACS LDL-C reduction and the exciting advancements on the horizon, this article provides a roadmap for clinicians navigating the intricate landscape of lipid-lowering therapies in CAD.

Expanding therapeutic options: overview of novel pharmacotherapies for dyslipidemia

INTRODUCTION

Dyslipidemia plays a crucial role in the development of atherosclerotic cardiovascular diseases.

AREAS COVERED

This article explores the emerging therapeutic targets for the treatment of dyslipidemia and provides novel insights into this field. Thus, it aims to contribute to the understanding and advancement of therapeutic options for managing dyslipidemia.

EXPERT OPINION

Optimizing the use of available first- and second-line lipid-lowering drugs allows us to adequately control low-density lipoprotein cholesterol (LDL-C) levels, even in statin-intolerant individuals and in patients at high and very high risk of developing cardiovascular diseases who must reach more aggressive LDL-C targets. The drugs under development will further improve our ability to manage the overall lipid-related cardiovascular disease risk and target other dyslipidemia biomarkers.

Established and Emerging Nucleic Acid Therapies for Familial Hypercholesterolemia

Familial hypercholesterolemia (FH) is a genetic disease that leads to elevated low-density lipoprotein cholesterol levels and risk of coronary heart disease. Current therapeutic options for FH remain relatively limited and only partially effective in both lowering low-density lipoprotein cholesterol and modifying coronary heart disease risk. The unique characteristics of nucleic acid therapies to target the underlying cause of the disease can offer solutions unachievable with conventional medications. DNA- and RNA-based therapeutics have the potential to transform the care of patients with FH. Recent advances are overcoming obstacles to clinical translation of nucleic acid-based medications, including greater stability of the formulations as well as site-specific delivery, making gene-based therapy for FH an alternative approach for treatment of FH.

Establishment of precise prevention strategies for the occurrence and progression of coronary atherosclerotic heart disease using machine learning

Background

Coronary atherosclerotic heart disease (CHD) is highly prevalent in Northwest China; however, effective preventive measures are limited. This study aimed to develop metabolic risk models tailored for the primary and secondary prevention of CHD in Northwest China.

Methods

This hospital-based cross-sectional study included 744 patients who underwent coronary angiography. Data on demographic characteristics, comorbidities, and serum biochemical indices of the participants were collected. Three machine learning algorithms-recursive feature elimination, random forest, and least absolute shrinkage and selection operator-were employed to construct risk models. Model validation was performed using receiver operating characteristic and calibration curves, and the optimal cutoff values for significant risk factors were determined.

Results

The predictive model for CHD onset included sex, overweight/obesity, and hemoglobin A1c (HbA1c) levels. For CHD progression to multiple coronary artery disease, the model included age, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and HbA1c levels. The model predicting an increased coronary Gensini score included sex, overweight/obesity, TC, LDL-C, high-density lipoprotein cholesterol, lipoprotein(a), and HbA1c levels. Notably, the optimal cutoff values for HbA1c and lipoprotein(a) for determining CHD progression were 6 % and 298 mg/L, respectively.

Conclusions

Robust metabolic risk models were established, offering significant value for both the primary and secondary prevention of CHD in Northwest China. Weight loss, strict hyperglycemic control, and improvement in dyslipidemia may help prevent or delay the occurrence and progression of CHD in this region.

Lipoprotein (a)-Related Inflammatory Imbalance: A Novel Horizon for the Development of Atherosclerosis

PURPOSE OF REVIEW

The primary objective of this review is to explore the pathophysiological roles and clinical implications of lipoprotein(a) [Lp(a)] in the context of atherosclerotic cardiovascular disease (ASCVD). We seek to understand how Lp(a) contributes to inflammation and arteriosclerosis, aiming to provide new insights into the mechanisms of ASCVD progression.

RECENT FINDINGS

Recent research highlights Lp(a) as an independent risk factor for ASCVD. Studies show that Lp(a) not only promotes the inflammatory processes but also interacts with various cellular components, leading to endothelial dysfunction and smooth muscle cell proliferation. The dual role of Lp(a) in both instigating and, under certain conditions, mitigating inflammation is particularly noteworthy. This review finds that Lp(a) plays a complex role in the development of ASCVD through its involvement in inflammatory pathways. The interplay between Lp(a) levels and inflammatory responses highlights its potential as a target for therapeutic intervention. These insights could pave the way for novel approaches in managing and preventing ASCVD, urging further investigation into Lp(a) as a therapeutic target.

Race/ethnicity and socioeconomic status affect the assessment of lipoprotein(a) levels in clinical practice

BACKGROUND AND OBJECTIVE

High Lp(a) levels are a risk factor for ASCVD, however Lp(a) ordering in clinical practice is low. This study examines how race/ethnicity and socioeconomic status influence Lp(a) ordering.

METHODS

This is a single center, retrospective study (2/1/2020-6/30/2023) using electronic medical records of adults with at least one personal ICD-10 diagnosis of ASCVD, aortic valve stenosis, resistant hypercholesterolemia (LDL-C >160 mg/dL on statin therapy), and family history of ASCVD or high Lp(a). We evaluated Lp(a) level differences among racial/ethnic groups and sexes. We also assessed associations between diagnosis type, diagnosis number, age at diagnosis, race/ethnicity, socioeconomic score (based on zip codes), public health coverage and the presence of Lp(a) orders.

RESULTS

4 % of our cohort (N=2,249 in 56,833) had an Lp(a) order (17.3 % of whom identified as Hispanic, 8.7 % non-Hispanic Black, 47.5 % non-Hispanic White, and 27 % Asian/other). Non-Hispanic Black and Hispanic patients had lower rates of Lp(a) orders (0.17 % and 0.28 %, respectively) when compared to non-Hispanic White patients (2.35 %), p < 0.001, however, their median Lp(a) levels were higher, p < 0.001. Individuals on Medicaid or belonging to deprived socioeconomic groups were less likely to have an Lp(a) order (IRR = 0.40, p < 0.001 and IRR = 0.39, p < 0.001 respectively). Certain diagnosis (carotid stenosis, family history of ASCVD and FH) and multiple diagnoses (>2) resulted in more Lp(a) orders compared to only one diagnosis (p < 0.001).

CONCLUSIONS

Lp(a) ordering is low in patients with or at risk for ASCVD. Non-Hispanic Black and Hispanic patients are less likely to have an Lp(a) order. Individuals on Medicaid and residing in socioeconomically deprived neighborhoods are less like have an Lp(a) order. Lp(a) orders depend on the type and number of patients' diagnoses.

Non-coding RNA therapeutics in the treatment of heart failure

Non-coding RNA (ncRNA) therapeutics can target either ncRNAs or conventional messenger RNA, offering both superior pharmacokinetics and selectivity to conventional therapies and addressing new, previously unexplored pathways. Although no ncRNA has yet been approved for the treatment of heart failure, in this review we present five most promising pathways and agents that either are in human clinical trials or offer great promise in the near future.

Research Hotspots and Development Trends on Apolipoprotein B in the Field of Atherosclerosis: A Bibliometric Analysis

BACKGROUND

Cardiovascular diseases caused by atherosclerosis (AS) are the leading causes of disability and death worldwide. Apolipoprotein B (ApoB), the core protein of low-density lipoproteins, is a major contributor to cardiovascular disease-related morbidity and mortality, with apolipoprotein B (ApoB) playing a critical role in its pathogenesis. However, no bibliometric studies on the involvement of ApoB in AS have been published. This study aimed to conduct a comprehensive bibliometric analysis to explore the current and future trends regarding the role of ApoB in AS.

METHODS

Utilizing the Web of Science Core Collection, a thorough search was conducted for ApoB in AS-related papers related to research on ApoB in the field of AS during 1991-2023. The analysis focused on annual publication trends, leading countries/regions and institutions, influential authors, journal and key journals. CiteSpace and VOSviewer were employed to visualize reference co-citations, and keyword co-occurrences, offering insights into the research landscape and emerging trends.

RESULTS

This bibliometric analysis employed network diagrams for cluster analysis of a total of 2105 articles and reviews, evidencing a discernible upward trend in annual publication volume. This corpus of research emanates from 76 countries/regions and 2343 organizations, illustrating the widespread international engagement in ApoB-related AS studies. Notably, the United States and the University of California emerge as the most prolific contributors, which underscores their pivotal roles in advancing this research domain. The thematic investigation has increasingly focused on elucidating the mechanistic involvement of ApoB in atherosclerosis, its potential as a diagnostic biomarker, and its implications for therapeutic strategies.

CONCLUSION

This bibliometric analysis provides the first comprehensive perspective on the evolving promise of ApoB in AS-related research, emphasizing the importance of this molecule in opening up new diagnostic and therapeutic avenues. This study emphasizes the need for continued research and interdisciplinary efforts to strengthen the fight against AS. Furthermore, it emphasizes the critical role of international collaboration and interdisciplinary exploration in leveraging new insights to achieve clinical breakthroughs, thereby addressing the complexities of AS by focusing on ApoB.

Consensus on lipoprotein(a) of the Spanish Society of Arteriosclerosis. Literature review and recommendations for clinical practice

The irruption of lipoprotein(a) (Lp(a)) in the study of cardiovascular risk factors is perhaps, together with the discovery and use of proprotein convertase subtilisin/kexin type 9 (iPCSK9) inhibitor drugs, the greatest novelty in the field for decades. Lp(a) concentration (especially very high levels) has an undeniable association with certain cardiovascular complications, such as atherosclerotic vascular disease (AVD) and aortic stenosis. However, there are several current limitations to both establishing epidemiological associations and specific pharmacological treatment. Firstly, the measurement of Lp(a) is highly dependent on the test used, mainly because of the characteristics of the molecule. Secondly, Lp(a) concentration is more than 80% genetically determined, so that, unlike other cardiovascular risk factors, it cannot be regulated by lifestyle changes. Finally, although there are many promising clinical trials with specific drugs to reduce Lp(a), currently only iPCSK9 (limited for use because of its cost) significantly reduces Lp(a). However, and in line with other scientific societies, the SEA considers that, with the aim of increasing knowledge about the contribution of Lp(a) to cardiovascular risk, it is relevant to produce a document containing the current status of the subject, recommendations for the control of global cardiovascular risk in people with elevated Lp(a) and recommendations on the therapeutic approach to patients with elevated Lp(a).

Recent updates on therapeutic targeting of lipoprotein(a) with RNA interference

PURPOSE OF REVIEW

RNA interference (RNAi)-based therapies that target specific gene products have impacted clinical medicine with 16 FDA approved drugs. RNAi therapy focused on reducing plasma lipoprotein(a) [Lp(a)] levels are under evaluation.

RECENT FINDINGS

RNAi-based therapies have made significant progress over the past 2 decades and currently consist of antisense oligonucleotides (ASO) and small interfering RNA (siRNA). Chemical modification of the RNA backbone and conjugation of siRNA enables efficient gene silencing in hepatocytes allowing development of effective cholesterol lowering therapies. Multiple lines of evidence suggest a causative role for Lp(a) in atherosclerotic cardiovascular disease, and recent analyses indicate that Lp(a) is more atherogenic than low density lipoprotein- cholesterol (LDL-C). These findings have led to the 'Lp(a) hypothesis' that lowering Lp(a) may significantly improve cardiovascular outcomes. Four RNAi-based drugs have completed early phase clinical trials demonstrating >80% reduction in plasma Lp(a) levels. Phase 3 clinical trials examining clinical outcomes with these agents are currently underway.

SUMMARY

Currently, four RNAi-based drugs have been shown to be effective in significantly lowering plasma Lp(a) levels. Clinical outcome data from phase 3 trials will evaluate the Lp(a) hypothesis.

New approaches to triglyceride reduction: Is there any hope left?

Triglycerides play a crucial role in the efficient storage of energy in the body. Mild and moderate hypertriglyceridemia (HTG) is a heterogeneous disorder with significant association with atherosclerotic cardiovascular disease (ASCVD), including myocardial infarction, ischemic stroke, and peripheral artery disease and represents an important component of the residual ASCVD risk in statin treated patients despite optimal low-density lipoprotein cholesterol reduction. Individuals with severe HTG (>1,000 mg/dL) rarely develop atherosclerosis but have an incremental incidence of acute pancreatitis with significant morbidity and mortality. HTG can occur from a combination of genetic (both mono and polygenic) and environmental factors including poor diet, low physical activity, obesity, medications, and diseases like insulin resistance and other endocrine pathologies. HTG represents a potential target for ASCVD risk and pancreatitis risk reduction, however data on ASCVD reduction by treating HTG is still lacking and HTG-associated acute pancreatitis occurs too rarely to effectively demonstrate treatment benefit. In this review, we address the key aspects of HTG pathophysiology and examine the mechanisms and background of current and emerging therapies in the management of HTG.

Fragment-based drug design of novel inhibitors targeting lipoprotein (a) kringle domain KIV-10-mediated cardiovascular disease

Cardiovascular diseases (CVDs) are the leading cause of death globally, attributed to a complex etiology involving metabolic, genetic, and protein-related factors. Lipoprotein(a) (Lp(a)), identified as a genetic risk factor, exhibits elevated levels linked to an increased risk of cardiovascular diseases. The lipoprotein(a) kringle domains have recently been identified as a potential target for the treatment of CVDs, in this study we utilized a fragment-based drug design approach to design a novel, potent, and safe inhibitor for lipoprotein(a) kringle domain. With the use of fragment library (61,600 fragments) screening, combined with analyses such as MM/GBSA, molecular dynamics simulation (MD), and principal component analysis, we successfully identified molecules effective against the kringle domains of Lipoprotein(a). The hybridization process (Breed) of the best fragments generated a novel 249 hybrid molecules, among them 77 exhibiting superior binding affinity (≤ -7 kcal/mol) compared to control AZ-02 (-6.9 kcal/mol), Importantly, the top ten molecules displayed high similarity to the control AZ-02. Among the top ten molecules, BR1 exhibited the best docking energy (-11.85 kcal/mol ), and higher stability within the protein LBS site, demonstrating the capability to counteract the pathophysiological effects of lipoprotein(a) [Lp(a)]. Additionally, principal component analysis (PCA) highlighted a similar trend of motion during the binding of BR1 and the control compound (AZ-02), limiting protein mobility and reducing conformational space. Moreover, ADMET analysis indicated favorable drug-like properties, with BR1 showing minimal violations of Lipinski's rules. Overall, the identified compounds hold promise as potential therapeutics, addressing a critical need in cardiovascular medicine. Further preclinical and clinical evaluations are needed to validate their efficacy and safety, potentially ushering in a new era of targeted therapies for CVDs.

Lipoprotein(a): Emerging insights and therapeutics

The strong association between lipoprotein (a) [Lp(a)] and atherosclerotic cardiovascular disease has led to considerations of Lp(a) being a potential target for mitigating residual cardiovascular risk. While approximately 20 % of the population has an Lp(a) level greater than 50 mg/dL, there are no currently available pharmacological lipid-lowering therapies that have demonstrated substantial reduction in Lp(a). Novel therapies to lower Lp(a) include antisense oligonucleotides and small-interfering ribonucleic acid molecules and have shown promising results in phase 2 trials. Phase 3 trials are currently underway and will test the causal relationship between Lp(a) and ASCVD and whether lowering Lp(a) reduces cardiovascular outcomes. In this review, we summarize emerging insights related to Lp(a)'s role as a risk-enhancing factor for ASCVD, association with calcific aortic stenosis, effects of existing therapies on Lp(a) levels, and variations amongst patient populations. The evolving therapeutic landscape of emerging therapeutics is further discussed.

Race/ethnicity and socioeconomic status affect the assessment of lipoprotein(a) levels in clinical practice

Background and Objective

High Lp(a) levels are a risk factor for ASCVD, however Lp(a) ordering in clinical practice is low. This study examines how race/ethnicity and socioeconomic status influence Lp(a) ordering.

Methods

This is a single center, retrospective study (2/1/2020-6/30/2023) using electronic medical records of adults with at least one ICD-10 diagnosis of ASCVD or resistant hyperlipidemia (LDL-C >160 mg/dL on statin therapy). We evaluated Lp(a) level differences among racial/ethnic groups and sexes. We also assessed associations between diagnosis type, diagnosis number, age at diagnosis, race, socioeconomic score (based on zip codes), public health coverage and presence of Lp(a) orders.

Results

4% of our cohort (N=56,833) had an Lp(a) order (17.3% Hispanic, 8.7% non-Hispanic Black, 47.5% non-Hispanic White and, 27% Asian/others). Non-Hispanic Black and Hispanic patients had lower rates of Lp(a) orders (0.17%, 0.28%, respectively) when compared to non-Hispanic White patients (2.35%), p<0.001, however, their median Lp(a) levels were higher. Individuals belonging to deprived socioeconomic groups or on Medicaid, were less likely to have an Lp(a) order (RR=0.39, p<0.001 and RR=0.40, p<0.001 respectively). Certain diagnoses (carotid stenosis, family history of ASCVD and FH) and multiple diagnoses (>2) resulted in more Lp(a) orders compared to those with only one diagnosis (p<0.001).

Conclusions

Lp(a) ordering is low in patients with ASCVD. Non-Hispanic Black and Hispanic patients at risk are less likely to have an Lp(a) order. Individuals residing in socioeconomically deprived neighborhoods and on Medicaid are also less like have Lp(a) order. Lp(a) orders depend on the type and number of patients' diagnoses.

Independent Relationship of Lipoprotein(a) and Carotid Atherosclerosis With Long-Term Risk of Cardiovascular Disease

BACKGROUND

Lipoprotein(a) (Lp(a)) is considered to be a causal risk factor of atherosclerotic cardiovascular disease (ASCVD), but whether there is an independent or joint association of Lp(a) and atherosclerotic plaque with ASCVD risk remains uncertain. This study aims to assess ASCVD risk independently or jointly conferred by Lp(a) and carotid atherosclerotic plaque.

METHODS AND RESULTS

A total of 5471 participants with no history of cardiovascular disease at baseline were recruited and followed up for ASCVD events (all fatal and nonfatal acute coronary and ischemic stroke events) over a median of 11.5 years. Independent association of Lp(a), or the joint association of Lp(a) and carotid plaque with ASCVD risk, was explored using Cox proportional hazards models. Overall, 7.6% of the participants (60.0±7.9 years of age; 2649 [48.4%] men) had Lp(a) ≥50 mg/dL, and 539 (8.4/1000 person-years) incident ASCVD events occurred. Lp(a) concentrations were independently associated with long-term risk of total ASCVD events, as well as coronary events and ischemic stroke events. Participants with Lp(a) ≥50 mg/dL had a 62% higher risk of ASCVD incidence (95% CI, 1.19-2.21) than those with Lp(a) <10 mg/dL, and they exhibited a 10-year ASCVD incidence of 11.7%. This association exists even after adjusting for prevalent plaque. Moreover, participants with Lp(a) ≥30 mg/dL and prevalent plaque had a significant 4.18 times higher ASCVD risk than those with Lp(a) <30 mg/dL and no plaque.

CONCLUSIONS

Higher Lp(a) concentrations are independently associated with long-term ASCVD risk and may exaggerate cardiovascular risk when concomitant with atherosclerotic plaque.

The joint association of lipoprotein(a) and Lp-PLA2 with the risk of stroke recurrence

BACKGROUND AND PURPOSE

Currently little is known about the joint association of lipoprotein (a) [Lp(a)] and Lipoprotein-associated phospholipase A2 (Lp-PLA2) with stroke recurrence.

METHODS

In this prospective multicenter cohort study, 10,675 consecutive acute ischemic stroke (IS) and transient ischemic attack patients (TIA) with Lp(a) and Lp-PLA2 were enrolled. The association of stroke recurrence within 1 year with Lp(a) and Lp-PLA2 was assessed using Cox proportional hazards models and Kaplan-Meier curves. The interaction between Lp(a) and Lp-PLA2 with stroke recurrence was evaluated by multiplicative and additive scales.

RESULTS

A significant joint association of Lp(a) and Lp-PLA2 with the risk of stroke recurrence was observed. Multivariate cox regression analysis demonstrated that the combination of elevated Lp(a) (≥ 50 mg/dL) and Lp-PLA2 (≥175.1 ng/ml) was independently associated with the risk of stroke recurrence (adjusted hazard ratio: 1.42; 95 % CI: 1.15-1.76). Both significant multiplicative [(exp(β3):1.63, 95 % CI: 1.17-2.29, P = 0.004] and additive interaction (RERI:0.55, 95 % CI: 0.20-0.90, P = 0.002; AP: 0.39, 95 %CI, 0.24-0.53) were observed between Lp(a) and Lp-PLA2.

CONCLUSIONS

Our results indicated that Lp(a) and Lp-PLA2 have a joint association with the risk of stroke recurrence in IS/TIA patients. Patients with concomitant presence of elevated Lp(a) and Lp-PLA2 have greater risk of stroke recurrence.

Lipoprotein(a), platelet function and cardiovascular disease

Lipoprotein(a) (Lp(a)) is associated with atherothrombosis through several mechanisms, including putative antifibrinolytic properties. However, genetic association studies have not demonstrated an association between high plasma levels of Lp(a) and the risk of venous thromboembolism, and studies in patients with highly elevated Lp(a) levels have shown that Lp(a) lowering does not modify the clotting properties of plasma ex vivo. Lp(a) can interact with several platelet receptors, providing biological plausibility for a pro-aggregatory effect. Observational clinical studies suggest that elevated plasma Lp(a) concentrations are associated with worse long-term outcomes in patients undergoing revascularization. Furthermore, in these patients, those with elevated plasma Lp(a) levels derive more benefit from prolonged dual antiplatelet therapy than those with normal Lp(a) levels. The ASPREE trial in healthy older individuals treated with aspirin showed a reduction in ischaemic events in those who had a single-nucleotide polymorphism in LPA that is associated with elevated Lp(a) levels in plasma, without an increase in bleeding events. In this Review, we re-examine the role of Lp(a) in the regulation of platelet function and suggest areas of research to define further the clinical relevance to cardiovascular disease of the observed associations between Lp(a) and platelet function.

Navigating the landscape of RNA delivery systems in cardiovascular disease therapeutics

Cardiovascular diseases (CVDs) stand as the leading cause of death worldwide, posing a significant global health challenge. Consequently, the development of innovative therapeutic strategies to enhance CVDs treatment is imperative. RNA-based therapies, encompassing non-coding RNAs, mRNA, aptamers, and CRISPR/Cas9 technology, have emerged as promising tools for addressing CVDs. However, inherent challenges associated with RNA, such as poor cellular uptake, susceptibility to RNase degradation, and capture by the reticuloendothelial system, underscore the necessity of combining these therapies with effective drug delivery systems. Various non-viral delivery systems, including extracellular vesicles, lipid-based carriers, polymeric and inorganic nanoparticles, as well as hydrogels, have shown promise in enhancing the efficacy of RNA therapeutics. In this review, we offer an overview of the most relevant RNA-based therapeutic strategies explored for addressing CVDs and emphasize the pivotal role of delivery systems in augmenting their effectiveness. Additionally, we discuss the current status of these therapies and the challenges that hinder their clinical translation.

The current status of lipoprotein (a) measurement in clinical biochemistry laboratories in the UK: Results of a 2021 national survey

BACKGROUND

Lipoprotein(a) (Lp(a)) is now established as a causal risk factor for cardiovascular disease (CVD) and accurate laboratory measurement is of pivotal importance in reducing Lp(a) associated risk. The consensus statement by HEART UK in 2019 included recommendations to improve standardisation of clinical laboratory measurement and reporting of Lp(a).

METHODS

A 16 question, electronic audit survey was circulated to 190 accredited clinical biochemistry laboratories to assess the adoption of these recommendations in the UK.

RESULTS

Responses were received from 65 of 190 laboratories (34%). Only 5 (8%) did not offer Lp(a) measurement. Of those providing the test, 23% (n = 14) offered an in-house service (IHS), the remaining laboratories (77%; n = 46) used an external referral service (ERS). The majority (10 of 14 or 71%) of IHS laboratories responded with details of their method, stating whether it minimised sensitivity to the effect of Lp(a) isoform size and used calibrators certified for traceability to the WHO/IFCC reference material, however, only a minority ERS laboratories (13 of the 46 or 28%) were able to specify the method used by their referral laboratory. Of the laboratories who specified their reporting units, 6 of 10 IHS and 7 of 23 ERS laboratories reported in nmol/L. Among the 60 laboratories who responded, the HEART UK recommendations appear to have been adopted in full by only 3 IHS laboratories.

CONCLUSIONS

Further efforts are needed to standardise the measurement and reporting of Lp(a) so that results and interpretation are comparable across clinical biochemistry laboratories in the UK.

Association of Lipoprotein(a) with arterial stiffness: A Mendelian randomization study

BACKGROUND

In this study we used Mendelian randomization (MR) to investigate the potential causal association of lipoprotein (a) [Lp(a)] levels with pulse wave velocity (PWV).

METHODS

Genetic variants associated with Lp(a) were retrieved from the UK Biobank GWAS (N = 290,497). A non- overlapping GWAS based on a European cohort (N = 7,000) was used to obtain genetic associations with PWV (outcome) and utilized two different measures for the same trait, brachial-ankle (baPWV) and carotid-femoral (cfPWV) PWV. We applied a two-sample MR using the inverse variance weighting method (IVW) and a series of sensitivity analyses for 170 SNPs that were selected as instrumental variables (IVs).

RESULTS

Our analyses do not support a causal association between Lp(a) and PWV for neither measurement [βiwv(baPWV) = -.0005, p = .8 and βiwv(cfPWV) = -.006, p = .16]. The above findings were consistent across sensitivity analyses including weighted median, mode-based estimation, MR-Egger regression and MR-PRESSO.

CONCLUSION

We did not find evidence indicating that Lp(a) is causally associated with PWV, the gold standard marker of arterial stiffness.

Trained immunity: General and emerging concepts

Over the past decade, compelling evidence has unveiled previously overlooked adaptive characteristics of innate immune cells. Beyond their traditional role in providing short, non-specific protection against pathogens, innate immune cells can acquire antigen-agnostic memory, exhibiting increased responsiveness to secondary stimulation. This long-term de-facto innate immune memory, also termed trained immunity, is mediated through extensive metabolic rewiring and epigenetic modifications. While the upregulation of trained immunity proves advantageous in countering immune paralysis, its overactivation contributes to the pathogenesis of autoinflammatory and autoimmune disorders. In this review, we present the latest advancements in the field of innate immune memory followed by a description of the fundamental mechanisms underpinning trained immunity generation and different cell types that mediate it. Furthermore, we explore its implications for various diseases and examine current limitations and its potential therapeutic targeting in immune-related disorders.

Impact of Elevated Lipoprotein A on Clinical Outcomes in Patients Undergoing Percutaneous Coronary Intervention: A Systematic Review and Meta-analysis

Lipoprotein(a) (Lp(a)) is an inherited lipoprotein particle associated with increased risk of atherosclerotic cardiovascular (CV) diseases. However, its impact on outcomes after percutaneous coronary intervention (PCI) remains unclear. The objective of this study was to assess the relationship between elevated Lp(a) levels and major adverse cardiovascular events (MACEs) and other outcomes in patients undergoing PCI. We systematically searched Embase, MEDLINE/PubMed, and Web of Science for studies published from 2015 to 2024 comparing CV outcomes between patients with elevated versus non-elevated Lp(a) levels after PCI. Primary outcome was MACE. Secondary outcomes included all-cause mortality, CV mortality, stroke, myocardial infarction, and revascularization. Risk ratios (RRs) were pooled using a random-effect model. Fifteen studies with 45,059 patients were included. Patients with elevated Lp(a) had a significantly higher risk of MACE (RR 1.38, 95% confidence interval (CI) 1.23-1.56). Elevated Lp(a) was also associated with increased risks of all-cause death (RR 1.26), CV death (RR 1.58), myocardial infarction (RR 1.44), revascularization (RR 1.38), and stroke (RR 1.18). Heterogeneity was considerable for some outcomes. This meta-analysis demonstrates that elevated Lp(a) levels are associated with worse CV outcomes, including higher rates of MACE, mortality, and recurrent ischemic events in patients undergoing PCI. Novel therapeutic approaches specifically targeting Lp(a) reduction may help mitigate residual CV risk in this high-risk population.

Recent Updates on Epigenetic-Based Pharmacotherapy for Atherosclerosis

Atherosclerosis is one of the most dominant pathological processes responsible in cardiovascular diseases (CVD) caused by cholesterol accumulation accompanied by inflammation in the arteries which will subsequently lead to further complications, including myocardial infarction and stroke. Although the incidence of atherosclerosis is decreasing in some countries, it is still considered the leading cause of death worldwide. Atherosclerosis is a vascular pathological process that is chronically inflammatory and is characterized by the invasion of inflammatory cells and cytokines. Many reports have unraveled the pivotal roles of epigenetics such as DNA methylation, post-translational histone modifications, and non-coding RNAs (ncRNAs) in atherogenesis, which regulate the expression of numerous genes related to various responsible pathways. Many studies have been conducted to develop new therapeutical approaches based on epigenetic changes for combating atherosclerosis. This review elaborates on recent updates on the development of new atherosclerosis drugs whose mechanism of action is associated with the modulation of DNA methylation, posttranslational histone modifications, and ncRNA-based gene regulation.

The Essence of Lipoproteins in Cardiovascular Health and Diseases Treated by Photodynamic Therapy

Lipids, together with lipoprotein particles, are the cause of atherosclerosis, which is a pathology of the cardiovascular system. In addition, it affects inflammatory processes and affects the vessels and heart. In pharmaceutical answer to this, statins are considered a first-stage treatment method to block cholesterol synthesis. Many times, additional drugs are also used with this method to lower lipid concentrations in order to achieve certain values of low-density lipoprotein (LDL) cholesterol. Recent advances in photodynamic therapy (PDT) as a new cancer treatment have gained the therapy much attention as a minimally invasive and highly selective method. Photodynamic therapy has been proven more effective than chemotherapy, radiotherapy, and immunotherapy alone in numerous studies. Consequently, photodynamic therapy research has expanded in many fields of medicine due to its increased therapeutic effects and reduced side effects. Currently, PDT is the most commonly used therapy for treating age-related macular degeneration, as well as inflammatory diseases, and skin infections. The effectiveness of photodynamic therapy against a number of pathogens has also been demonstrated in various studies. Also, PDT has been used in the treatment of cardiovascular diseases, such as atherosclerosis and hyperplasia of the arterial intima. This review evaluates the effectiveness and usefulness of photodynamic therapy in cardiovascular diseases. According to the analysis, photodynamic therapy is a promising approach for treating cardiovascular diseases and may lead to new clinical trials and management standards. Our review addresses the used therapeutic strategies and also describes new therapeutic strategies to reduce the cardiovascular burden that is induced by lipids.

State of Gene Therapy for Monogenic Cardiovascular Diseases

Over the past 2 decades, significant efforts have been made to advance gene therapy into clinical practice. Although successful examples exist in other fields, gene therapy for the treatment of monogenic cardiovascular diseases lags behind. In this review, we (1) highlight a brief history of gene therapy, (2) distinguish between gene silencing, gene replacement, and gene editing technologies, (3) discuss vector modalities used in the field with a special focus on adeno-associated viruses, (4) provide examples of gene therapy approaches in cardiomyopathies, channelopathies, and familial hypercholesterolemia, and (5) present current challenges and limitations in the gene therapy field.

Apolipoprotein(a) production and clearance are associated with plasma IL-6 and IL-18 levels, dependent on ethnicity

BACKGROUND AND AIMS

High plasma lipoprotein (a) [Lp(a)] levels are associated with increased atherosclerotic cardiovascular disease (ASCVD), in part attributed to elevated inflammation. High plasma Lp(a) levels inversely correlate with apolipoprotein (a) [(APO(a)] isoform size. APO(a) isoform size is negatively associated with APO(a) production rate (PR) and positively associated with APO(a) fractional catabolic rate (FCR). We asked whether APO(a) PR and FCR (kinetics) are associated with plasma levels of interleukin (IL)-6 and IL-18, pro-inflammatory interleukins that promote ASCVD.

METHODS

We used samples from existing data of APO(a) kinetic studies from an ethnically diverse cohort (n = 25: 10 Black, 9 Hispanic, and 6 White subjects) and assessed IL-6 and IL-18 plasma levels. We performed multivariate linear regression analyses to examine the relationships between predictors APO(a) PR or APO(a) FCR, and outcome variables IL-6 or IL-18. In these analyses, we adjusted for parameters known to affect Lp(a) levels and APO(a) PR and FCR, including race/ethnicity and APO(a) isoform size.

RESULTS

APO(a) PR and FCR were positively associated with plasma IL-6, independent of isoform size, and dependent on race/ethnicity. APO(a) PR was positively associated with plasma IL-18, independent of isoform size and race/ethnicity. APO(a) FCR was not associated with plasma IL-18.

CONCLUSIONS

Our studies demonstrate a relationship between APO(a) PR and FCR and plasma IL-6 or IL-18, interleukins that promote ASCVD. These studies provide new insights into Lp(a) pro-inflammatory properties and are especially relevant in view of therapies targeting APO(a) to decrease cardiovascular risk.

Novel Therapies for Lipoprotein(a): Update in Cardiovascular Risk Estimation and Treatment

PURPOSE OF REVIEW

Lipoprotein(a) is an important causal risk factor for cardiovascular disease but currently no available medication effectively reduces lipoprotein(a). This review discusses recent findings regarding lipoprotein(a) as a causal risk factor and therapeutic target in cardiovascular disease, it reviews current clinical recommendations, and summarizes new lipoprotein(a) lowering drugs.

RECENT FINDINGS

Epidemiological and genetic studies have established lipoprotein(a) as a causal risk factor for cardiovascular disease and mortality. Guidelines worldwide now recommend lipoprotein(a) to be measured once in a lifetime, to offer patients with high lipoprotein(a) lifestyle advise and initiate other cardiovascular medications. Clinical trials including antisense oligonucleotides, small interfering RNAs, and an oral lipoprotein(a) inhibitor have shown great effect on lowering lipoprotein(a) with reductions up to 106%, without any major adverse effects. Recent clinical phase 1 and 2 trials show encouraging results and ongoing phase 3 trials will hopefully result in the introduction of specific lipoprotein(a) lowering drugs to lower the risk of cardiovascular disease.

Association of a genetic variant in angiopoietin-like 3 with serum HDL-C and risk of cardiovascular disease: A study of the MASHAD cohort over 6 years

BACKGROUND

Loss-of-function (LOF) variants of the angiopoietin-like 3 (ANGPTL3) gene are reported to be associated with serum triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C) concentrations and thereby affect the risk of cardiovascular disease (CVD).

OBJECTIVE

In the present study, we examined the association of rs10789117 in the ANGPTL 3 gene locus and the risk of CVD in the group of people who were part of the Mashhad-Stroke and Heart-Atherosclerotic-Disorders (MASHAD) cohort.

METHODS

One thousand and two healthy individuals enrolled in this study of whom 849 subjects were healthy and 153 subjects developed CVD outcomes after 6 years of follow-up. After a 12-h overnight fasting, 20 mL of blood samples were collected for the measurement of fasting blood glucose and lipid profile. DNA was extracted, and the Tetra-ARMS PCR (amplification refractory mutation system) was used for genotyping of rs10789117 in the ANGPTL3 gene. The genotype frequencies of the variant of rs10789117 in the ANGPTL3 gene were estimated using χ2 tests. Eventually, the statistical analysis was done by SPSS version 20.

RESULTS

Individuals with AC/CC genotypes (rs10789117) were found to have to greater risk of CVD events compared to AA genotype (OR = 1.43, 95%CI = 1.01-2.02, p = 0.041). There was a 1.3-fold increase in cardiovascular events in individuals carrying the C allele of rs10789117 variant compared to non-carriers (OR = 1.32, 95%CI = 1.06-1.72, p value = 0.038). There were significant differences between different genotypes for serum triglyceride levels within the control group, but this difference was not significant in the group with CVD. Moreover, there was a significant association between CC genotype and CVD risk in the individuals with a normal serum HDL-C.

CONCLUSION

We have found that a rs10789117 C>A in ANGPTL3 gene polymorphism was associated with incident CVD events, and this may be of value as a risk stratification biomarker in CVD in the Iranian population.

Targeting lncRNA16 by GalNAc-siRNA conjugates facilitates chemotherapeutic sensibilization via the HBB/NDUFAF5/ROS pathway

Chemoresistance is a significant barrier to effective cancer treatment. Potential mechanisms for chemoresistance include reactive oxygen species (ROS) accumulation and expression of chemoresistance-promoting genes. Here, we report a novel function of lncRNA16 in the inhibition of ROS generation and the progression of chemoresistance. By analyzing the serum levels of lncRNA16 in a cohort of 35 patients with non-small cell lung cancer (NSCLC) and paired serum samples pre- and post-treatment from 10 NSCLC patients receiving neoadjuvant platinum-based chemotherapy, performing immunohistochemistry (IHC) assays on 188 NSCLC tumor samples, using comprehensive identification of RNA-binding proteins by mass spectrometry (ChIRP-MS) assays, as well as RNA immunoprecipitation (RIP) and RNA pull-down analyses, we discovered that patients with increased serum levels of lncRNA16 exhibited a poor response to platinum-based chemotherapy. The expression of hemoglobin subunit beta (HBB) and NDUFAF5 significantly increases with the development of chemoresistance. LncRNA16 binds to HBB and promotes HBB accumulation by inhibiting autophagy. LncRNA16 can also inhibit ROS generation via the HBB/NDUFAF5 axis and function as a scaffold to facilitate the colocalization of HBB and NDUFAF5 in the mitochondria. Importantly, preclinical studies in mouse models of chemo-resistant NSCLC have suggested that lncRNA16 targeting by trivalent N-acetylgalactosamine (GalNAc)-conjugated siRNA restores chemosensitivity and results in tumor growth inhibition with no detectable toxicity in vivo. Overall, lncRNA16 is a promising therapeutic target for overcoming chemoresistance, and the combination of first-line platinum-based chemotherapy with lncRNA16 intervention can substantially enhance anti-tumor efficacy.

Oxidized phospholipids in cardiovascular disease

Prolonged or excessive exposure to oxidized phospholipids (OxPLs) generates chronic inflammation. OxPLs are present in atherosclerotic lesions and can be detected in plasma on apolipoprotein B (apoB)-containing lipoproteins. When initially conceptualized, OxPL-apoB measurement in plasma was expected to reflect the concentration of minimally oxidized LDL, but, surprisingly, it correlated more strongly with plasma lipoprotein(a) (Lp(a)) levels. Indeed, experimental and clinical studies show that Lp(a) particles carry the largest fraction of OxPLs among apoB-containing lipoproteins. Plasma OxPL-apoB levels provide diagnostic information on the presence and extent of atherosclerosis and improve the prognostication of peripheral artery disease and first and recurrent myocardial infarction and stroke. The addition of OxPL-apoB measurements to traditional cardiovascular risk factors improves risk reclassification, particularly in patients in intermediate risk categories, for whom improving decision-making is most impactful. Moreover, plasma OxPL-apoB levels predict cardiovascular events with similar or greater accuracy than plasma Lp(a) levels, probably because this measurement reflects both the genetics of elevated Lp(a) levels and the generalized or localized oxidation that modifies apoB-containing lipoproteins and leads to inflammation. Plasma OxPL-apoB levels are reduced by Lp(a)-lowering therapy with antisense oligonucleotides and by lipoprotein apheresis, niacin therapy and bariatric surgery. In this Review, we discuss the role of role OxPLs in the pathophysiology of atherosclerosis and Lp(a) atherogenicity, and the use of OxPL-apoB measurement for improving prognosis, risk reclassification and therapeutic interventions.

Targeting Lipoprotein(a): Can RNA Therapeutics Provide the Next Step in the Prevention of Cardiovascular Disease?

Numerous genetic and epidemiologic studies have demonstrated an association between elevated levels of lipoprotein(a) (Lp[a]) and cardiovascular disease. As a result, lowering Lp(a) levels is widely recognized as a promising strategy for reducing the risk of new-onset coronary heart disease, stroke, and heart failure. Lp(a) consists of a low-density lipoprotein-like particle with covalently linked apolipoprotein A (apo[a]) and apolipoprotein B-100, which explains its pro-thrombotic, pro-inflammatory, and pro-atherogenic properties. Lp(a) serum concentrations are genetically determined by the apo(a) isoform, with shorter isoforms having a higher rate of particle synthesis. To date, there are no approved pharmacological therapies that effectively reduce Lp(a) levels. Promising treatment approaches targeting apo(a) expression include RNA-based drugs such as pelacarsen, olpasiran, SLN360, and lepodisiran, which are currently in clinical trials. In this comprehensive review, we provide a detailed overview of RNA-based therapeutic approaches and discuss the recent advances and challenges of RNA therapeutics specifically designed to reduce Lp(a) levels and thus the risk of cardiovascular disease.

Executive summary of the Hellenic Atherosclerosis Society guidelines for the diagnosis and treatment of dyslipidemias - 2023

Atherosclerotic cardiovascular disease (ASCVD) remains the main cause of death worldwide, and thus its prevention, early diagnosis and treatment is of paramount importance. Dyslipidemia represents a major ASCVD risk factor that should be adequately managed at different clinical settings. 2023 guidelines of the Hellenic Atherosclerosis Society focus on the assessment of ASCVD risk, laboratory evaluation of dyslipidemias, new and emerging lipid-lowering drugs, as well as diagnosis and treatment of lipid disorders in women, the elderly and in patients with familial hypercholesterolemia, acute coronary syndromes, heart failure, stroke, chronic kidney disease, diabetes, autoimmune diseases, and non-alcoholic fatty liver disease. Statin intolerance is also discussed.

Renal function alters the association of lipoprotein(a) with cardiovascular outcomes in patients undergoing percutaneous coronary intervention: a prospective cohort study

Background and hypothesis

Lipoprotein(a) [Lp(a)] and renal dysfunction are both independent risk factors for cardiovascular disease. However, it remains unclear whether renal function mediates the association between Lp(a) and cardiovascular outcomes in patients undergoing percutaneous coronary intervention (PCI).

Methods

From a large prospective cohort study, 10 435 eligible patients undergoing PCI from January 2013 to December 2013 were included in our analysis. Patients were stratified into three renal function groups according to their baseline estimated glomerular filtration rate (eGFR) (<60; 60-90; ≥90 ml/min/1.73 m2). The primary endpoint was a composite of all-cause death, nonfatal MI, ischemic stroke, and unplanned revascularization [major adverse cardiac and cerebrovascular events (MACCE)].

Results

Over a median follow-up of 5.1 years, a total of 2144 MACCE events occurred. After multivariable adjustment, either eGFR <60 ml/min/1.73 m2 or elevated Lp(a) conferred a significantly higher MACCE risk. Higher Lp(a) was significantly associated with an increased risk of MACCE in patients with eGFR <60 ml/min/1.73 m2. However, this association was weakened in subjects with only mild renal impairment and diminished in those with normal renal function. A significant interaction for MACCE between renal categories and Lp(a) was observed (P = 0.026). Patients with concomitant Lp(a) ≥30 mg/dl and eGFR <60 ml/min/1.73 m2 experienced worse cardiovascular outcomes compared with those without.

Conclusion

The significant association between Lp(a) and cardiovascular outcomes was mediated by renal function in patients undergoing PCI. Lp(a)-associated risk was more pronounced in patients with worse renal function, suggesting close monitoring and aggressive management are needed in this population.

Diacylglycerols and Lysophosphatidic Acid, Enriched on Lipoprotein(a), Contribute to Monocyte Inflammation

BACKGROUND

Oxidized phospholipids play a key role in the atherogenic potential of lipoprotein(a) (Lp[a]); however, Lp(a) is a complex particle that warrants research into additional proinflammatory mediators. We hypothesized that additional Lp(a)-associated lipids contribute to the atherogenicity of Lp(a).

METHODS

Untargeted lipidomics was performed on plasma and isolated lipoprotein fractions. The atherogenicity of the observed Lp(a)-associated lipids was tested ex vivo in primary human monocytes by RNA sequencing, ELISA, Western blot, and transendothelial migratory assays. Using immunofluorescence staining and single-cell RNA sequencing, the phenotype of macrophages was investigated in human atherosclerotic lesions.

RESULTS

Compared with healthy individuals with low/normal Lp(a) levels (median, 7 mg/dL [18 nmol/L]; n=13), individuals with elevated Lp(a) levels (median, 87 mg/dL [218 nmol/L]; n=12) demonstrated an increase in lipid species, particularly diacylglycerols (DGs) and lysophosphatidic acid (LPA). DG and the LPA precursor lysophosphatidylcholine were enriched in the Lp(a) fraction. Ex vivo stimulation with DG(40:6) demonstrated a significant upregulation in proinflammatory pathways related to leukocyte migration, chemotaxis, NF-κB (nuclear factor kappa B) signaling, and cytokine production. Functional assessment showed a dose-dependent increase in the secretion of IL (interleukin)-6, IL-8, and IL-1β after DG(40:6) and DG(38:4) stimulation, which was, in part, mediated via the NLRP3 (NOD [nucleotide-binding oligomerization domain]-like receptor family pyrin domain containing 3) inflammasome. Conversely, LPA-stimulated monocytes did not exhibit an inflammatory phenotype. Furthermore, activation of monocytes by DGs and LPA increased their transendothelial migratory capacity. Human atherosclerotic plaques from patients with high Lp(a) levels demonstrated colocalization of Lp(a) with M1 macrophages, and an enrichment of CD68+IL-18+TLR4+ (toll-like receptor) TREM2+ (triggering receptor expressed on myeloid cells) resident macrophages and CD68+CASP1+ (caspase) IL-1B+SELL+ (selectin L) inflammatory macrophages compared with patients with low Lp(a). Finally, potent Lp(a)-lowering treatment (pelacarsen) resulted in a reduction in specific circulating DG lipid subspecies in patients with cardiovascular disease with elevated Lp(a) levels (median, 82 mg/dL [205 nmol/L]).

CONCLUSIONS

Lp(a)-associated DGs and LPA have a potential role in Lp(a)-induced monocyte inflammation by increasing cytokine secretion and monocyte transendothelial migration. This DG-induced inflammation is, in part, NLRP3 inflammasome dependent.

Lipoprotein(a): A Review of Risk Factors, Measurements, and Novel Treatment Modalities

The study of lipoprotein(a) [Lp(a)] has long been a source of interest as a possible independent risk factor for atherosclerotic cardiovascular disease (ASCVD). The results of large sample observational studies, genome-wide association studies, and Mendelian randomization studies have been strong indicators supporting the link between ASCVD and Lp(a) despite early studies, with less sensitive assays, failing to show a connection. The recommendations for the indications and frequency of testing Lp(a) levels vary between US, Canadian, and European organizations due to the uncertain role of Lp(a) in ASCVD. The innovation of recent therapies, such as antisense oligonucleotides and small interfering RNA, designed to specifically target and reduce Lp(a) levels by targeting mRNA translation have once more thrust LP(a) into the spotlight of inquiry. These emerging modalities serve the dual purpose of definitively elucidating the connection between elevated Lp(a) levels and atherosclerotic cardiovascular risk, as well as the possibility of providing clinicians with the tools necessary to manage elevated Lp(a) levels in vulnerable populations. This review seeks to examine the mechanisms of atherogenicity of Lp(a) and explore the most current pharmacologic therapies currently in development.

Elevated lipoprotein(a) increases risk of subsequent major adverse cardiovascular events (MACE) and coronary revascularisation in incident ASCVD patients: A cohort study from the UK Biobank

BACKGROUND AND AIMS

Elevated lipoprotein(a) [Lp(a)] is a genetic driver for atherosclerotic cardiovascular disease (ASCVD). We aimed to provide novel insights into the associated risk of elevated versus normal Lp(a) levels on major adverse cardiovascular events (MACE) in an incident ASCVD cohort.

METHODS

This was an observational cohort study of incident ASCVD patients. MACE counts and incidence rates (IRs) per 100-person-years were reported for patients with normal (<65 nmol/L) and elevated (>150 nmol/L) Lp(a) within the first year after incident ASCVD diagnosis and overall follow-up. Cox proportional hazard models quantified the risk of MACE associated with a 100 nmol/L increase in Lp(a).

RESULTS

The study cohort included 32,537 incident ASCVD patients; 5204 with elevated and 22,257 with normal Lp(a). Of those with elevated Lp(a), 41.2% had a subsequent MACE, versus 35.61% with normal Lp(a). Within the first year of follow-up, the IRs of composite MACE and coronary revascularisation were significantly higher (p < 0.001) in patients with elevated versus normal Lp(a) (IR difference 6.79 and 4.66). This trend was also observed in the overall follow-up (median 4.7 years). Using time to first subsequent MACE, a 100 nmol/L increase in Lp(a) was associated with an 8.0% increased risk of composite MACE, and 18.6% increased risk of coronary revascularisation during the overall follow-up period.

CONCLUSIONS

The association of elevated Lp(a) with increased risk of subsequent MACE and coronary revascularisation highlights a population who may benefit from earlier and more targeted intervention for cardiovascular risk including Lp(a), particularly within the first year after ASCVD diagnosis. Proactive Lp(a) testing as part of routine clinical practice can help identify and better manage these higher-risk individuals.

Safety and Tolerability of GalNAc3-Conjugated Antisense Drugs Compared to the Same-Sequence 2'-O-Methoxyethyl-Modified Antisense Drugs: Results from an Integrated Assessment of Phase 1 Clinical Trial Data

The triantennary N-acetylgalactosamine (GalNAc3) cluster has demonstrated the utility of receptor-mediated uptake of ligand-conjugated antisense drugs targeting RNA expressed by hepatocytes. GalNAc3-conjugated 2'-O-methoxyethyl (2'MOE) modified antisense oligonucleotides (ASOs) have demonstrated a higher potency than the unconjugated form to support lower doses for an equivalent pharmacological effect. We utilized the Ionis integrated safety database to compare four GalNAc3-conjugated and four same-sequence unconjugated 2'MOE ASOs. This assessment evaluated data from eight randomized placebo-controlled dose-ranging phase 1 studies involving 195 healthy volunteers (79 GalNAc3 ASO, 24 placebo; 71 ASO, 21 placebo). No safety signals were identified by the incidence of abnormal threshold values in clinical laboratory tests for either ASO group. However, there was a significant increase in mean alanine transaminase levels compared with placebo in the upper dose range of the unconjugated 2'MOE ASO group. The mean percentage of subcutaneous injections leading to local cutaneous reaction was 30-fold lower in the GalNAc3-conjugated ASO group compared with the unconjugated ASO group (0.9% vs. 28.6%), with no incidence of flu-like reactions (0.0% vs. 0.7%). Three subjects (4.2%) in the unconjugated ASO group discontinued dosing. An improvement in the overall safety and tolerability profile of GalNAc3-conjugated 2'MOE ASOs is evident in this comparison of short-term clinical data in healthy volunteers.

Patterns of Lipid Lowering Therapy Use Among Older Adults in a Managed Care Advantage Plan in the United States

Background: The prevalence of cardiovascular events is increasing. There are many new lipids lowering therapies available in recent years. Increased evidence through literature and guidelines suggests that the use of lipid lowering therapy (LLT) benefits patients who are at risk for cardiovascular events. Objective: The objective of this study was to describe the current LLT use as well as patterns of treatment modification among adults ≥ 65 years. Methods: A retrospective analysis of administrative claims data between January 2016 and May 2018 was conducted. Patients with a LLT refill and continuous enrollment during 1-year prior and 1-year follow-up were identified. The treatment episodes captured were interruption of therapy, intensity changes, dose changes, treatment augmentation, switching, and discontinuation. An analysis of treatment patterns among patients ≥75 years was also performed. Results: The study included 14,360 patients with a LLT of which 99% of patients were on statins as monotherapy or combination. Overall non-statin therapy use either as monotherapy or combination was 2.1%. There were significant differences among new initiators and existing users of therapy. Among prevalent users 57.4% had no changes in the follow-up period, 13.6% interrupted therapy, and 6.6% discontinued. Among new users, 47.9% patients had interrupted therapy, 25% had no changes, and 21.9% discontinued therapy. Conclusion: Most patients were on monotherapy and statins with low non-statin use. The new users among them were more likely to discontinue and interrupt therapy, highlighting the limitations and issues that older patients face that need to increase adherence.

Residual cardiovascular risk: When should we treat it?

Cardiovascular disease (CVD) still being the most common cause of death in worldwide. In spite of development of new lipid-lowering therapies which optimize low-density lipoprotein cholesterol (LDL-c) levels, recurrence of CVD events implies addressing factors related with residual cardiovascular (CV) risk. The key determinants of residual CV risk include triglyceride-rich lipoproteins (TRLs) and remnant cholesterol (RC), lipoprotein(a) [Lp(a)] and inflammation including its biochemical markers such as high sensitivity C reactive protein (hs-CRP). On the other hand, unhealthy lifestyle habits, environmental pollution, residual thrombotic risk and the residual metabolic risk determined by obesity and type 2 diabetes (T2D) have a specific weight in the residual CV risk. New pharmacologic therapies and pathways are being explored such as inhibition of apolipoprotein C-III (apoC-III) and angiopoietin-related protein 3 (ANGPTL3) in order to explore if a reduction in TRLs and RC reduce CVD events. Therapeutic target of inflammation plays an attractive way to reduce the atherosclerotic process and to date, approved therapies as colchicine plays a beneficial effect in chronic inflammation and residual CV risk. Lp(a) constitutes one of the most residual CV risk factor due to linkage with CVD and aortic valve stenosis. New and hopeful treatments including antisense oligonucleotides (ASO) and small-interfering ribonucleic acid (siRNA) which interfere in LP(a) codification have been developed to achieve an adequate control in Lp(a) levels. This review points out the paradigms of residual CV risk, discus how we should manage their features and summarize the different therapies targeting each residual CV risk factor.

Relationship Between Lipoprotein(a), Renal Function Indicators, and Chronic Kidney Disease: Evidence From a Large Prospective Cohort Study

BACKGROUND

Chronic kidney disease (CKD) poses a significant global public health challenge. While lipoprotein(a) (Lp[a]) has been established as a significant factor in cardiovascular disease, its connection to CKD risk remains a topic of debate. Existing evidence indicates diverse risks of kidney disease among individuals with various renal function indicators, even when within the normal range.

OBJECTIVE

This study aims to investigate the joint associations between different renal function indicators and Lp(a) regarding the risks of incident CKD in the general population.

METHODS

The analysis involved a cohort of 329,415 participants without prior CKD who were enrolled in the UK Biobank between 2006 and 2010. The participants, with an average age of 56 (SD 8.1) years, included 154,298/329,415 (46.84%) males. At baseline, Lp(a) levels were measured using an immunoturbidimetric assay and classified into 2 groups: low (<75 nmol/L) and high (≥75 nmol/L). To assess participants' baseline renal function, we used the baseline urine albumin-to-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR). The relationship between Lp(a), renal function indicators, and the risk of CKD was evaluated using multivariable Cox regression models. These models were adjusted for various factors, including sociodemographic variables, lifestyle factors, comorbidities, and laboratory measures.

RESULTS

A total of 6003 incident CKD events were documented over a median follow-up period of 12.5 years. The association between elevated Lp(a) levels and CKD risk did not achieve statistical significance among all participants, with a hazard ratio (HR) of 1.05 and a 95% CI ranging from 0.98 to 1.13 (P=.16). However, a notable interaction was identified between Lp(a) and UACR in relation to CKD risk (P for interaction=.04), whereas no significant interaction was observed between Lp(a) and eGFR (P for interaction=.96). When compared with the reference group with low Lp(a) and low-normal UACR (<10 mg/g), the group with high Lp(a) and low-normal UACR exhibited a nonsignificant association with CKD risk (HR 0.98, 95% CI 0.90-1.08; P=.74). By contrast, both the low Lp(a) and high-normal UACR (≥10 mg/g) group (HR 1.16, 95% CI 1.08-1.24; P<.001) and the high Lp(a) and high-normal UACR group (HR 1.32, 95% CI 1.19-1.46; P<.001) demonstrated significant associations with increased CKD risks. In individuals with high-normal UACR, elevated Lp(a) was linked to a significant increase in CKD risk, with an HR of 1.14 and a 95% CI ranging from 1.03 to 1.26 (P=.01). Subgroup analyses and sensitivity analyses consistently produced results that were largely in line with the main findings.

CONCLUSIONS

The analysis revealed a significant interaction between Lp(a) and UACR in relation to CKD risk. This implies that Lp(a) may act as a risk factor for CKD even when considering UACR. Our findings have the potential to provide valuable insights into the assessment and prevention of CKD, emphasizing the combined impact of Lp(a) and UACR from a public health perspective within the general population. This could contribute to enhancing public awareness regarding the management of Lp(a) for the prevention of CKD.

LP(a): Structure, Genetics, Associated Cardiovascular Risk, and Emerging Therapeutics

Lipoprotein(a) [Lp(a)] is a molecule bound to apolipoprotein(a) with some similarity to low-density lipoprotein cholesterol (LDL-C), which has been found to be a risk factor for cardiovascular disease (CVD). Lp(a) appears to induce inflammation, atherogenesis, and thrombosis. Approximately 20% of the world's population has increased Lp(a) levels, determined predominantly by genetics. Current clinical practices for the management of dyslipidemia are ineffective in lowering Lp(a) levels. Evolving RNA-based therapeutics, such as the antisense oligonucleotide pelacarsen and small interfering RNA olpasiran, have shown promising results in reducing Lp(a) levels. Phase III pivotal cardiovascular outcome trials [Lp(a)HORIZON and OCEAN(a)] are ongoing to evaluate their efficacy in secondary prevention of major cardiovascular events in patients with elevated Lp(a). The future of cardiovascular residual risk reduction may transition to a personalized approach where further lowering of either LDL-C, triglycerides, or Lp(a) is selected after high-intensity statin therapy based on the individual risk profile and preferences of each patient.

Novel therapeutic targets and emerging treatments for atherosclerotic cardiovascular disease

Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of morbidity and mortality worldwide. Even with excellent control of low-density lipoprotein cholesterol (LDL-C) levels, adverse cardiovascular events remain a significant clinical problem worldwide, including among those without any traditional ASCVD risk factors. It is necessary to identify novel sources of residual risk and to develop targeted strategies that address them. Lipoprotein(a) has become increasingly recognized as a new cardiovascular risk determinant. Large-scale clinical trials have also signalled the potential additive cardiovascular benefits of decreasing triglycerides beyond lowering LDL-C levels. Since CANTOS (Anti-inflammatory Therapy with Canakinumab for Atherosclerotic Disease) demonstrated that antibodies against interleukin-1β may decrease recurrent cardiovascular events in secondary prevention, various anti-inflammatory medications used for rheumatic conditions and new monoclonal antibody therapeutics have undergone rigorous evaluation. These data build towards a paradigm shift in secondary ASCVD prevention, underscoring the value of targeting multiple biological pathways in the management of both lipid levels and systemic inflammation. Evolving knowledge of the immune system, and the gut microbiota may result in opportunities for modifying previously unrecognized sources of residual inflammatory risk. This review provides an overview of novel therapeutic targets for ASCVD and emerging treatments with a focus on mechanisms, efficacy, and safety.

Lipoprotein (a) as a Biomarker for Cardiovascular Diseases and Potential New Therapies to Mitigate Risk

BACKGROUND

Lipoprotein (a) [Lp(a)] is a molecule that induces inflammation of the blood vessels, atherogenesis, valvular calcification, and thrombosis.

METHODS

We review the available evidence that suggests that high Lp(a) levels are associated with a persisting risk for atherosclerotic cardiovascular diseases despite optimization of established risk factors, including low-density lipoprotein cholesterol (LDL-C) levels.

OBSERVATIONS

Approximately a quarter of the world population have Lp(a) levels of >50 mg/dL (125 nmol/L), a level associated with elevated cardiovascular risk. Lifestyle modification, statins, and ezetimibe do not effectively lower Lp(a) levels, while proprotein convertase subtilisin/kexin type 9 (PCSK-9) inhibitors and niacin only lower Lp(a) levels modestly. We describe clinical studies suggesting that gene silencing therapeutics, such as small interfering RNA (siRNA) and antisense oligonucleotide targeting Lp(a), offer a targeted approach with the potential for safe and robust Lp(a)- lowering with only a few doses (3-4) per year. Prospective randomized phase 3 studies are ongoing to validate safety, effectiveness in improving hard clinical outcomes, and tolerability to assess these therapies.

CONCLUSION

Several emerging treatments with robust Lp(a)-lowering effects may significantly lower atherosclerotic cardiovascular risk.