The effect of statin therapy withdrawal on monocyte subsets

Imaging angiogenesis in atherosclerosis in large arteries with 68Ga-NODAGA-RGD PET/CT: relationship with clinical atherosclerotic cardiovascular disease

BACKGROUND

Integrin alpha-V-beta-3 (αvβ3) pathway is involved in intraplaque angiogenesis and inflammation and represents a promising target for molecular imaging in cardiovascular diseases such as atherosclerosis. The aim of this study was to assess the clinical correlates of arterial wall accumulation of ⁶⁸Ga-NODAGA-RGD, a specific α_vβ₃ integrin ligand for PET.

MATERIALS AND METHODS

The data of 44 patients who underwent ⁶⁸Ga-NODAGA-RGD PET/CT scans were retrospectively analyzed. Tracer accumulation in the vessel wall of major arteries was analyzed semi-quantitatively by blood-pool-corrected target-to-background ratios. Tracer uptake was compared with clinically documented atherosclerotic cardiovascular disease, cardiovascular risk factors and calcified plaque burden. Data were compared using the Mann-Whitney U test, Pearson correlation and Spearman correlation.

RESULTS

⁶⁸Ga-NODAGA-RGD arterial uptake was significantly higher in patients with previous clinically documented atherosclerotic cardiovascular disease (mean TBR 2.44 [2.03-2.55] vs. 1.81 [1.56-1.96], p = 0.001) and showed a significant correlation with prior cardiovascular or cerebrovascular event (r = 0.33, p = 0.027), BMI (ρ = 0.38, p = 0.01), plaque burden (ρ = 0.31, p = 0.04) and hypercholesterolemia (r = 0.31, p = 0.04).

CONCLUSIONS

⁶⁸Ga-NODAGA-RGD holds promise as a non-invasive marker of disease activity in atherosclerosis, providing information about intraplaque angiogenesis.

Protocol for systematic review and meta-analysis: impact of statins as immune-modulatory agents on inflammatory markers in adults with chronic diseases

INTRODUCTION

Statins, also known as 3-hydroxy-3-methylglutaryl coenzyme-A (HMG-CoA) reductase inhibitors, are lipid-lowering agents that are central in preventing or reducing the complications of atherosclerotic cardiovascular disease. Because statins have anti-inflammatory properties, there is considerable interest in their therapeutic potential in other chronic inflammatory conditions. We aim to identify the statin with the greatest ability to reduce systemic inflammation, independent of the underlying disease entity.

METHODS AND ANALYSIS

We aim to conduct a comprehensive search of published and peer-reviewed randomised controlled clinical trials, with at least one intervention arm of a Food & Drug Administration-licensed or European Medicines Agency-licensed statin and a minimum treatment duration of 12 weeks. Our objective is to investigate the effect of statins (atorvastatin, fluvastatin, pitavastatin, pravastatin, rosuvastatin, simvastatin) on lipid profile, particularly, cholesterol low-density lipoprotein and inflammation markers such as high-sensitive C reactive protein (hsCRP), CRP, tumour necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), IL-6, IL-8, soluble cluster of differentiation 14 (sCD14) or sCD16 in adults, published in the last 20 years (between January 1999 and December 2019). We aim to identify the most potent statin to reduce systemic inflammation and optimal dosing. The following databases will be searched: Medline, Scopus, Web of Science and Cochrane Library of Systematic Reviews. The risk of bias of included studies will be assessed by Cochrane Risk of Bias Tool and Quality Assessment Tool for Quantitative Studies. The quality of studies will be assessed, to show uncertainty, by the Jadad Score. If sufficient evidence is identified, a meta-analysis will be conducted with risk ratios or ORs with 95% CIs in addition to mean differences.

ETHICS AND DISSEMINATION

Ethics approval is not required as no primary data will be collected. Results will be presented at conferences and published in a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42020169919.

Statins for neuroprotection in spontaneous intracerebral hemorrhage

Statins, a common drug class for treatment of dyslipidemia, may be neuroprotective for spontaneous intracerebral hemorrhage (ICH) by targeting secondary brain injury pathways in the surrounding brain parenchyma. Statin-mediated neuroprotection may stem from downregulation of mevalonate and its derivatives, targeting key cell signaling pathways that control proliferation, adhesion, migration, cytokine production, and reactive oxygen species generation. Preclinical studies have consistently demonstrated the neuroprotective and recovery enhancement effects of statins, including improved neurologic function, reduced cerebral edema, increased angiogenesis and neurogenesis, accelerated hematoma clearance, and decreased inflammatory cell infiltration. Retrospective clinical studies have reported reduced perihematomal edema, lower mortality rates, and improved functional outcomes in patients who were taking statins before ICH. Several clinical studies have also observed lower mortality rates and improved functional outcomes in patients who were continued or initiated on statins after ICH. Subgroup analysis of a previous randomized trial has raised concerns of a potentially elevated risk of recurrent ICH in patients with previous hemorrhagic stroke who are administered statins. However, most statin trials failed to show an association between statin use and increased hemorrhagic stroke risk. Variable statin dosing, statin use in the pre-ICH setting, and selection biases have limited rigorous investigation of the effects of statins on post-ICH outcomes. Future prospective trials are needed to investigate the association between statin use and outcomes in ICH.

Immunotropic Effects and Proposed Mechanism of Action for 3-Hydroxy-3-methylglutaryl-coenzyme A Reductase Inhibitors (Statins)

Inhibitors of HMG-CoA reductase (statins) are the major group of lipid-lowering drugs. Along with hypocholesterolemic activity, statins exhibit anti-inflammatory and immunomodulatory properties that expand their clinical use, particularly, in the treatment of chronic inflammatory and autoimmune disorders. In this review, we critically analyze the data of statin effects on immune cells (e.g., monocytes and T cells) involved in the development of atherosclerosis and other chronic inflammatory diseases. We (i) discuss the properties of statins and routes of cell entry, as well as their major intracellular targets; (ii) evaluate the data on the effects of statins on the subset composition of circulatory monocytes, ability of monocytes to migrate to the site of inflammation (cell motility and expression of adhesion molecules and chemokine receptors), production of cytokines, matrix metalloproteinases, and reactive oxygen species by monocytes/macrophages, and antigen-presenting activity in peripheral blood monocyte-derived dendritic cells; and (iii) summarize the data on the regulation of proliferation and differentiation of various CD4+ T cell subsets (type 1/2/17 helper T cells and regulatory T cells) by statins.

[68Ga]Pentixafor-PET/MRI for the detection of Chemokine receptor 4 expression in atherosclerotic plaques

PURPOSE

The expression of chemokine receptor type 4 (CXCR4) was found co-localized with macrophages on the atherosclerotic vessel wall and participated in the initial emigration of leukocytes. Gallium-68 [⁶⁸Ga]Pentixafor has recently been introduced for the imaging of atherosclerosis by targeting CXCR4. We sought to evaluate human atherosclerotic lesions using [⁶⁸Ga]Pentixafor PET/MRI.

METHODS

Thirty-eight oncology patients underwent [⁶⁸Ga]Pentixafor PET/MR imaging at baseline. Maximum standardized uptake values (SUV_max) were derived from hot lesions in seven arterial segments and target-to-blood ratios (TBR) were calculated. ANOVA post-hoc and paired t test were performed for statistical comparison, Spearman's correlation coefficient between uptake ratios and cardiovascular risk factors were assessed. The reproducibility of [⁶⁸Ga]Pentixafor PET/MRI was assessed in seven patients with a follow-up exanimation by Pearson's regression and Bland-Altman plots analysis.

RESULTS

Thirty-four of 38 patients showed 611 focal [⁶⁸Ga]Pentixafor uptake that followed the contours of the large arteries. Both prevalence and mean TBR_max were highest in the descending aorta. There were significantly higher TBR values found in men (1.9 ± 0.3) as compared to women (1.7 ± 0.2; p < 0.05). Patients with mean TBR_max > 1.7 showed a significantly higher incidence of diabetes, hypertension hypercholesterolemia and history of cardiovascular disease than patients with mean TBR_max ≤ 1.7. [⁶⁸Ga]Pentixafor uptake showed a good reproducibility (r = 0.6, p < 0.01), and there was no difference between the mean TBR_max values of plaque lesions (TBR_baseline1.8 ± 0.3 vs TBR_follow-up1.8 ± 0.3) (p = 0.9).

CONCLUSION

Patients with high arterial uptake showed increased incidence of cardiovascular risk factors, suggesting a potential role of [⁶⁸Ga]Pentixafor in characterization of atherosclerosis.

Role and analysis of monocyte subsets in cardiovascular disease. Joint consensus document of the European Society of Cardiology (ESC) Working Groups "Atherosclerosis & Vascular Biology" and "Thrombosis"

Monocytes as cells of the innate immunity are prominently involved in the development of atherosclerotic lesions. The heterogeneity of blood monocytes has widely been acknowledged by accumulating experimental and clinical data suggesting a differential, subset-specific contribution of the corresponding subpopulations to the pathology of cardiovascular and other diseases. This document re-evaluates current nomenclature and summarises key findings on monocyte subset biology to propose a consensus statement about phenotype, separation and quantification of the individual subsets.

Statin withdrawal beyond acute phase affected outcome of thrombolytic stroke patients: an observational retrospective study

Statin withdrawal is associated with deleterious outcome on stroke patients. Whether risk changes over time, depends on concomitant treatment of intravenous thrombolysis, or both remains to be clarified. We assessed the influence of statin withdrawal within 3 weeks while initiated in acute phase (72 hours) among patients receiving intravenous thrombolysis.This was a monocentered retrospective observational study enrolling intravenous thrombolytic stroke patients from June 2009 to May 2014. Consecutive patients were distinguished into 3 groups according to the initiation and withdrawal of statin: the reference group (not received statin in 72 hours after stroke onset); the continued group (initiated statin therapy in 72 hours and continued for at least 3 weeks); the withdrawal group (initiated statin in 72 hours and discontinued within 3 weeks). All reasons for cessation were recorded. The effects of statin withdrawal on short-, mid-, and long-term outcomes were evaluated as neurologic improvement (NIH Stroke Scale [NIHSS] score improvement ≥4 from baseline or later NIHSS = 0), death or poor outcome (modified Rankin Scale [mRS] ≥4), and favorable outcome (mRS ≤2). We further evaluate statin withdrawal effects in cardioembolic stroke patients for these outcomes.Among 443 IVT patients enrolled, 367 were included in the final study population. There were 88, 188, and 91 patients in the reference, continued, and withdrawal groups, respectively. Multivariable logistic regression showed that statin withdrawal compared with the reference was related to a lower possibility of long-term favorable outcome (OR = 0.45, 95% CI [0.22, 0.90], P = 0.024). Compared with the continued group, the adjusted OR of statin withdrawal was 0.40 (95% CI [0.22, 0.72], P = 0.002) and 2.52 (95% CI [1.34, 4.75], P = 0.004) for long-term favorable and poor/death outcomes, respectively. Also, results were similar for cardioembolic stroke patients (OR = 0.35, 95% CI [0.14, 0.89], P = 0.027 of favorable outcome and OR = 3.62, 95% CI [1.37, 9.62], P = 0.010 of poor/death outcome).In a real-world setting, for stroke patients receiving intravenous thrombolysis, statin withdrawal within 3 weeks initiating in 72 hours may have a harmful effect on the long-term neurologic outcome, even in cardioembolic stroke patients.

Monocyte subset distribution in patients with stable atherosclerosis and elevated levels of lipoprotein(a)

Background

Lipoprotein(a) (Lp(a)) is a proatherogenic plasma lipoprotein currently established as an independent risk factor for the development of atherosclerotic disease and as a predictor for acute thrombotic complications. In addition, Lp(a) is the major carrier of proinflammatory oxidized phospholipids (OxPL). Today, atherosclerosis is considered to be an inflammatory disease of the vessel wall in which monocytes and monocyte-derived macrophages are crucially involved. Circulating monocytes can be divided according to their surface expression pattern of CD14 and CD16 into at least 3 subsets with distinct inflammatory and atherogenic potential.

Objective

The aim of this study was to examine whether elevated levels of Lp(a) and OxPL on apolipoprotein B-100–containing lipoproteins (OxPL/apoB) are associated with changes in monocyte subset distribution.

Methods

We included 90 patients with stable coronary artery disease. Lp(a) and OxPL/apoB were measured, and monocyte subsets were identified as classical monocytes (CMs; CD14++CD16−), intermediate monocytes (IMs; CD14++CD16+), and nonclassical monocytes (NCMs; CD14+CD16++) by flow cytometry.

Results

In patients with elevated levels of Lp(a) (>50 mg/dL), monocyte subset distribution was skewed toward an increase in the proportion of IM (7.0 ± 3.8% vs 5.2 ± 3.0%; P = .026), whereas CM (82.6 ± 6.5% vs 82.0 ± 6.8%; P = .73) and NCM (10.5 ± 5.3 vs 12.8 ± 6.0; P = .10) were not significantly different. This association was independent of clinical risk factors, choice of statin treatment regime, and inflammatory markers. In addition, OxPL/apoB was higher in patients with elevated Lp(a) and correlated with IM but not CM and NCM.

Conclusions

In conclusion, we provide a potential link between elevated levels of Lp(a) and a proatherogenic distribution of monocyte subtypes in patients with stable atherosclerotic disease.

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Lipoprotein(a) serves as an independent risk factor in atherosclerotic disease.

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Monocyte subsets exhibit distinct inflammatory and atherogenic properties.

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Patients with elevated levels of Lp(a) show a shift towards intermediate monocytes.

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This association was independent of clinical properties and inflammatory markers.

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Those patients also exhibited higher OxPL/apoB concentrations.

Association of small dense LDL serum levels and circulating monocyte subsets in stable coronary artery disease

Objective

Atherosclerosis is considered to be an inflammatory disease in which monocytes and monocyte-derived macrophages play a key role. Circulating monocytes can be divided into three distinct subtypes, namely in classical monocytes (CM; CD14++CD16-), intermediate monocytes (IM; CD14++CD16+) and non-classical monocytes (NCM; CD14+CD16++). Low density lipoprotein particles are heterogeneous in size and density, with small, dense LDL (sdLDL) crucially implicated in atherogenesis. The aim of this study was to examine whether monocyte subsets are associated with sdLDL serum levels.

Methods

We included 90 patients with angiographically documented stable coronary artery disease and determined monocyte subtypes by flow cytometry. sdLDL was measured by an electrophoresis method on polyacrylamide gel.

Results

Patients with sdLDL levels in the highest tertile (sdLDL≥4mg/dL;T3) showed the highest levels of pro-inflammatory NCM (15.2±7% vs. 11.4±6% and 10.9±4%, respectively; p<0.01) when compared with patients in the middle (sdLDL=2-3mg/dL;T2) and lowest tertile (sdLDL=0-1mg/dL;T1). Furthermore, patients in the highest sdLDL tertile showed lower CM levels than patients in the middle and lowest tertile (79.2±8% vs. 83.9±7% and 82.7±5%; p<0.01 for T3 vs. T2+T1). Levels of IM were not related to sdLDL levels (5.6±4% vs. 4.6±3% vs. 6.4±3% for T3, T2 and T1, respectively). In contrast to monocyte subset distribution, levels of circulating pro- and anti-inflammatory markers were not associated with sdLDL levels.

Conclusion

The atherogenic lipoprotein fraction sdLDL is associated with an increase of NCM and a decrease of CM. This could be a new link between lipid metabolism dysregulation, innate immunity and atherosclerosis.

The CXCL12/CXCR4 chemokine ligand/receptor axis in cardiovascular disease

The chemokine receptor CXCR4 and its ligand CXCL12 play an important homeostatic function by mediating the homing of progenitor cells in the bone marrow and regulating their mobilization into peripheral tissues upon injury or stress. Although the CXCL12/CXCR4 interaction has long been regarded as a monogamous relation, the identification of the pro-inflammatory chemokine macrophage migration inhibitory factor (MIF) as an important second ligand for CXCR4, and of CXCR7 as an alternative receptor for CXCL12, has undermined this interpretation and has considerably complicated the understanding of CXCL12/CXCR4 signaling and associated biological functions. This review aims to provide insight into the current concept of the CXCL12/CXCR4 axis in myocardial infarction (MI) and its underlying pathologies such as atherosclerosis and injury-induced vascular restenosis. It will discuss main findings from in vitro studies, animal experiments and large-scale genome-wide association studies. The importance of the CXCL12/CXCR4 axis in progenitor cell homing and mobilization will be addressed, as will be the function of CXCR4 in different cell types involved in atherosclerosis. Finally, a potential translation of current knowledge on CXCR4 into future therapeutical application will be discussed.