Lipoprotein(a) and the atherosclerotic burden - Should we wait for clinical trial evidence before taking action?

Lipoprotein(a) as a Risk Factor for Recurrent Ischemic Stroke in Type 2 Diabetes

Objective

This study aimed to investigate the effect of LP(a) on recurrent ischemic stroke among persons with and without diabetes, providing a basis for the precise management of patients with recurrent ischemic stroke with diabetes in clinical practice.

Methods

This study was conducted on consecutive patients with cerebral infarction diagnosed between January 2019 and March 2023 in the Second Hospital of Hebei Medical University. Stratified analyses were performed according to LP(a) level (≤/>90th percentile) and logistic regression modeling was performed to investigate the relationship between LP(a) and recurrent ischemic stroke with or without T2DM.

Results

In the final enrollment of 2029 patients, the number of recurrent ischemic stroke according to LP(a) >90th percentile combined with T2DM was 59.15%, which was significantly higher than in LP(a) ≤90th percentile combined with T2DM (46.17%, P=0.039). After multivariate adjustment, LP(a) >90th percentile emerged as an independent risk factor for patients with T2DM (OR=2.062, 95% CI 1.218-3.489, P=0.007). In patients with large artery atherosclerotic ischemic stroke, LP(a) was an independent risk factor for recurrent ischemic stroke in diabetic patients (OR=2.553, 95%CI 1.385-4.707, P = 0.003), while this was not in non-diabetic patients (P = 0.228).

Conclusion

LP(a) is an independent risk factor for recurrent ischemic stroke in the diabetic population but not in nondiabetic individuals. Simple categorization based on the presence or absence of comorbid T2DM significantly influences the association between LP(a) and recurrent ischemic stroke. Therefore, in clinical practice, for ischemic stroke patients with comorbid diabetes, the LP(a) level should be more strictly controlled.

Deciphering Acute Coronary Syndromes Pathobiology Through Proteomics

Acute coronary syndrome (ACS) refers to a spectrum of conditions characterized by a sudden decrease in blood flow to the heart. This includes unstable angina, the mildest form, as well as non-ST- and ST-segment elevation myocardial infarction. The primary cause of ACS is typically the rupture or erosion of an atherosclerotic plaque in a coronary artery, resulting in the formation of a blood clot that can, partially or completely, block the blood flow to the heart muscle. The ongoing discovery and comprehension of emerging biomarkers for atherosclerosis could enhance our capacity to predict future events, particularly when integrated alongside traditional risk factors in assessing overall risk profiles. With advancements in proteomic technologies, large-scale approaches have been increasingly instrumental in unraveling pathways implicated in atherosclerotic degeneration and identifying novel circulating markers, which may serve as early diagnostic indicators or targets for innovative therapies. Over recent decades, numerous matrices including plasma, urine, microparticles, lipoproteins, atherosclerotic plaque extracts and secretomes, as well as thrombi, have been examined to address these questions. Furthermore, proteomics has been applied to various experimental models of atherosclerosis to deepen our understanding of the mechanisms underlying atherogenesis. This review offers a critical overview of the past two decades of untargeted omics research focused on identifying circulating and tissue biomarkers relevant to ACS.

Emerging oral therapeutic strategies for inhibiting PCSK9

Pharmacological inhibition of Proprotein Convertase Subtilisin/Kexin 9 (PCSK9) have been firmly established to be an effective approach to reduce low-density lipoprotein (LDL) cholesterol levels and cardiovascular events. Subcutaneous administration of monoclonal antibodies (evolocumab and alirocumab) every 2 or 4 weeks determined a 60 % reduction of LDL cholesterol levels, while the GalNac-siRNA anti PCSK9 (inclisiran) provided an effective lipid lowering activity (-50 %) after an initial subcutaneous dose, repeated after 3 months and followed by a maintenance dose every 6 months. Although these two approaches have the potentiality to bring the majority of patients at high and very-high cardiovascular risk to the appropriate LDL cholesterol targets, their cost and subcutaneous administration represent a strong limitation for their large-scale use. These problems could be overcome by the development of small chemical molecules anti PCSK9 as oral therapy for controlling hypercholesterolemia. In the present review, we summarized the pharmacological properties of oral anti PCSK9 molecules that are currently under clinical development (DC371739, CVI-LM001, and AZD0780), including the mimetic peptides enlicitide decanoate (MK-0616) and NNC0385-0434.

Hypercholesterolemia and inflammation-Cooperative cardiovascular risk factors

BACKGROUND

Maintaining low concentrations of plasma low-density lipoprotein cholesterol (LDLc) over time decreases the number of LDL particles trapped within the artery wall, slows the progression of atherosclerosis and delays the age at which mature atherosclerotic plaques develop. This substantially reduces the lifetime risk of atherosclerotic cardiovascular disease (ASCVD) events. In this context, plaque development and vulnerability result not only from lipid accumulation but also from inflammation.

RESULTS

Changes in the composition of immune cells, including macrophages, dendritic cells, T cells, B cells, mast cells and neutrophils, along with altered cytokine and chemokine release, disrupt the equilibrium between inflammation and anti-inflammatory mechanisms at plaque sites. Considering that it is not a competition between LDLc and inflammation, but instead that they are partners in crime, the present narrative review aims to give an overview of the main inflammatory molecular pathways linked to raised LDLc concentrations and to describe the impact of lipid-lowering approaches on the inflammatory and lipid burden. Although remarkable changes in LDLc are driven by the most recent lipid lowering combinations, the relative reduction in plasma C-reactive protein appears to be independent of the magnitude of LDLc lowering.

CONCLUSION

Identifying clinical biomarkers of inflammation (e.g. interleukin-6) and possible targets for therapy holds promise for monitoring and reducing the ASCVD burden in suitable patients.