Diversity of macrophage phenotypes and responses in atherosclerosis

PEGNB-Heparin-Liposome composite hydrogels for in situ spraying and ultra-fast adhesion: meeting the challenges of endothelial repair of vascular injury

Carotid atherosclerosis is an essential cause of transient cerebral ischemia, stroke, and other cerebrovascular diseases, and carotid endarterectomy (CEA) is currently the most effective treatment for removing plaque and restoring the vascular lumen. However, the CEA disrupts the integrity and functionality of the endothelium and predisposes it to complications such as restenosis and thrombosis. Hydrogels can closely mimic the natural extracellular matrix, allowing a wide tuning of physical and chemical properties. These properties make hydrogels the most promising candidate materials for the repair of vascular injured intima. In this study, a multifunctional intimal repair hydrogel of poly(ethylene glycol)-norbornene (PEGNB)/ Heparin/ Liposome is proposed with the advantages of ultra-rapid adhesion to the wet tissue of the vascular inner wall, maintenance of adhesion stability under continuous erosion by blood flow. The hydrogel was supplemented with poly(vinyl butyral) (PVB) to reduce its swelling rate, and Rapamycin (RAPA) was encapsulated in this study as the drug into the cationic liposomes. This composite multifunctional (PNHB@Lip(RAPA)) hydrogel has exhibited outstanding anti-coagulation properties, markedly suppressed the proliferation and migration of SMCs, and displayed favourable cytocompatibility and blood compatibility. Concurrently, the capacity of the PNHB@Lip(RAPA) hydrogel to stimulate endovascular regeneration and deter restenosis and thrombus formation was validated through carotid intima damage repair experiments. These findings collectively indicate that the PNHB@Lip(RAPA) hydrogel represents a promising material for intimal injury repair, offering innovative insights into intimal repair methodologies. STATEMENT OF SIGNIFICANCE: Carotid atherosclerosis is a leading cause of transient cerebral ischemia, stroke, and cerebrovascular disorders. Although carotid endarterectomy (CEA) effectively removes plaques, it damages endothelial integrity, increasing the risk of restenosis and thrombosis. To address this, we developed PNHB@Lip(RAPA), a multifunctional intimal repair hydrogel composed of PEGNB, heparin, and rapamycin-encapsulated liposomes. This hydrogel rapidly adheres to wet vascular walls, resists blood flow erosion, and exhibits low swelling. The hydrogel demonstrates superior anticoagulation, inhibits smooth muscle cell proliferation and migration, and shows favourable cytocompatibility. Experimental results confirm its ability to promote endovascular regeneration while preventing restenosis and thrombosis. In summary, PNHB@Lip(RAPA) hydrogel is a promising material for intimal repair, offering innovative solutions to improve CEA postoperative outcomes.

Bioinformatics analysis to investigate the potential relationship between mitochondrial structure and function-related genes and the immune microenvironment in atherosclerosis

Objective

This study aims to elucidate the interactions between genes associated with mitochondrial structure and function and the immune microenvironment in atherosclerosis.

Methods

Differentially expressed mitochondria-related genes (DE-MRGs) were identified through the analysis of two gene expression datasets, GSE100927 and GSE159677, in conjunction with a list of mitochondria-related genes sourced from the MitoCarta3.0 database. The immune profile of infiltrating immune cells in atherosclerotic carotid artery (CA) patients compared to controls (CTLs) was assessed using CIBERSORT. Potential target genes were screened based on Spearman correlation analysis between specific DE-MRGs and differentially expressed immune cells. Furthermore, the correlation between characterized DE-MRGs and immune cells in AS was examined at the single-cell level, and the expression of key genes was validated in vitro.

Results

Our study identified a robust association between four key genes-C15orf48, UCP2, PPIF, and MGST1-among 15 DE-MRGs, and immune macrophage polarization. These genes exhibited alterations corresponding to the degree of macrophage differentiation in AS. Additionally, Gene Set Enrichment Analysis (GSEA) revealed that C15orf48, UCP2, PPIF, and MGST1 modulate multiple immune pathways within the body. The mRNA expression levels of these four key genes in AS were confirmed via quantitative real-time PCR (qRT-PCR), with results aligning with bioinformatics predictions. Compared to the control group, the expression levels of C15orf48, UCP2, and PPIF were significantly elevated in AS macrophages, whereas MGST1 expression was notably reduced in AS macrophages. Consequently, these mitochondria-related genes-C15orf48, UCP2, PPIF, and MGST1-may influence the immune microenvironment in AS by modulating macrophage differentiation.

Conclusion

C15orf48, UCP2, PPIF, and MGST1 may serve as potential therapeutic targets for enhancing the atherosclerotic immune microenvironment in future interventions.

High-density lipoprotein-based nanoplatforms for macrophage-targeted diagnosis and therapy of atherosclerosis

Atherosclerosis, the primary cause of cardiovascular disease, which has the highest mortality worldwide, is a chronic inflammatory disease mainly induced by excessive lipid accumulation in plaque macrophages. Lipid-laden macrophages are crucial at all stages of atherosclerotic lesion progression and are, thus, regarded as popular therapeutic targets for atherosclerosis. High-density lipoprotein (HDL), an endogenous particle with excellent atherosclerotic plaque-homing properties, is considered a potential therapeutic agent for treating atherosclerosis. Based on the excellent properties of HDL, reconstituted HDL (rHDL), with physiological functions similar to those of its natural counterparts, have been successfully prepared as therapeutics and are also recognized as a potential nanoplatform for delivering drugs or contrast agents to atherosclerotic plaques owing to their high biocompatibility, amphiphilic structure, and macrophage-targeting capability. In this review, we focus on the (a) important role of macrophages in atherosclerotic lesions, (b) biological properties of rHDL as a delivery nanoplatform in atherosclerotic diseases, and (c) multiple applications of rHDL in the diagnosis and treatment of atherosclerosis. We systematically summarize the novel applications of rHDL with unique advantages in atherosclerosis, aiming to provide specific insights and inspire additional innovative research in this field.

Interaction between lipid metabolism and macrophage polarization in atherosclerosis

Atherosclerosis (AS) is a chronic inflammatory condition associated with lipid deposition. The interaction between abnormal lipid metabolism and the inflammatory response has been identified as the underlying cause of AS. Lipid metabolism disorders are considered the basis of atherosclerotic lesion formation and macrophages are involved in the entire process of AS formation. Macrophages have a high degree of plasticity, and the change of their polarization direction can determine the progress or regression of AS. The disturbances in bioactive lipid metabolism affect the polarization of different phenotypes of macrophages, thus, affecting lipid metabolism and the expression of key signal factors. Therefore, understanding the interaction between lipid metabolism and macrophages as well as their key targets is important for preventing and treating AS and developing new drugs. Recent studies have shown that traditional Chinese medicines play a positive role in the prevention and treatment of AS, providing a basis for clinical individualized treatment.

Probiotic membrane vesicles ameliorate atherosclerotic plaques by promoting lipid efflux and polarization of foamy macrophages

Foamy macrophages are pivotal contributors to the development and progression of atherosclerotic plaques, posing a substantial threat to human health. Presently, there is no pharmaceutical intervention available to effectively eliminate foamy macrophages. In this study, we demonstrate that probiotic membrane vesicles (MVs) can induce atherosclerotic plaque regression by modulating foamy macrophages. MVs isolated from Lactobacillus rhamnosus exhibited a specific uptake by foamy macrophages. Near-infrared fluorescence (NIRF) imaging, aortic oil red O staining, and hematoxylin and eosin staining showed reductions in the plaque area following MVs treatment. Mechanistically, bioinformatics analysis provided insights into how MVs exert their effects, revealing that they promote lipid efflux and macrophage polarization. Notably, MVs treatment upregulated NR1H3, which in turn increased ABCA1 expression, facilitating lipid efflux from foamy macrophages. Moreover, MVs shifted macrophage polarization from a pro-inflammatory M1 phenotype to an anti-inflammatory M2 phenotype, highlighting their potential to create a more protective environment against plaque progression. This study is significant as it introduces MVs as a novel therapeutic platform for the targeted delivery of anti-inflammatory agents to atherosclerotic sites. By specifically modulating macrophage function, MVs hold considerable potential for the treatment of atherosclerosis and related cardiovascular diseases, addressing an unmet need in current therapeutic strategies.

Iron, lipid peroxidation, and ferroptosis play pathogenic roles in atherosclerosis

Oxidation of lipids, excessive cell death, and iron deposition are prominent features of human atherosclerotic plaques. While extensive research has established the detrimental roles of lipid oxidation and apoptosis in atherosclerosis development, the involvement of iron in atherogenesis is not yet fully understood. With the emergence of an iron-dependent form of cell death termed ferroptosis, new attention has been brought to the complex inter-play among iron, ferroptosis, and atherosclerosis. Mechanistically, ferroptosis is caused by the lethal accumulation of iron-mediated lipid peroxides. Emerging studies have underscored ferroptosis as a contributor to worsened atherosclerosis. Herein, we review the evidence that oxidative damage and iron overload in the context of atherosclerosis may promote ferroptosis within plaques. Furthermore, we summarize recent findings of lipid peroxidation, thereby potentially ferroptosis, in various plaque cell types-such as endothelial cells, macrophages, dendritic cells, T cells, and vascular smooth muscle cells-across different stages of atherosclerosis. Understanding how these processes influence atherosclerotic plaque progression may permit targeting stage-dependent ferroptosis in each cell population and could provide a rationale for developing cell type-specific intervention strategies to mitigate atherogenic ferroptosis effectively.

The Role of Macrophages in Atherosclerosis: Participants and Therapists

Currently, atherosclerosis, characterized by the dysfunction of lipid metabolism and chronic inflammation in the intimal space of the vessel, is considered to be a metabolic disease. As the most abundant innate immune cells in the body, macrophages play a key role in the onset, progression, or regression of atherosclerosis. For example, macrophages exhibit several polarization states in response to microenvironmental stimuli; an increasing proportion of macrophages, polarized toward M2, can suppress inflammation, scavenge cell debris and apoptotic cells, and contribute to tissue repair and fibrosis. Additionally, specific exosomes, generated by macrophages containing certain miRNAs and effective efferocytosis of macrophages, are crucial for atherosclerosis. Therefore, macrophages have emerged as a novel potential target for anti-atherosclerosis therapy. This article reviews the role of macrophages in atherosclerosis from different aspects: origin, phenotype, exosomes, and efferocytosis, and discusses new approaches for the treatment of atherosclerosis.

Dysregulated cholesterol uptake and efflux of bone marrow-derived α-SMA+ macrophages contribute to atherosclerotic plaque formation

Macrophages play differential roles in the pathogenesis of atherosclerosis due to their different phenotypes. Although α-SMA+ macrophages have been found to present in bone marrow and atherosclerotic plaques, their role in atherosclerosis remains unclear. By performing partial carotid ligation (PCL) on monocyte/macrophage lineage-tracked mice, we observed bone marrow-derived α-SMA+ macrophages in the subendothelium and atherosclerotic plaques under disturbed flow conditions. The functional role of α-SMA+ macrophages in atherosclerotic plaque formation was examined using macrophage-specific Acta2 knockout (Acta2MKO) mice generated by crossing Acta2f/f transgenic mice with LysM-Cre mice. The size of the aortic plaques was 77.43% smaller in Acta2MKO mice than in Acta2f/f mice following adeno-associated virus-mutant PCSK9 injection and high-fat diet (HFD) feeding for 12 weeks. A significant reduction in lipid deposition, macrophage infiltration and the α-SMA+ area was observed in the aortic roots of Acta2MKO mice compared with Acta2f/f mice. Mechanistically, using Acta2-overexpressing Raw264.7 cells (Acta2hi cells) and bone marrow-derived macrophages (BMDMs) from Acta2MKO mice (Acta2MKO BMDMs), we showed that macrophage α-SMA increased the expression of the scavenger receptor SR-A, induced Ox-LDL binding and uptake, and reduced the level of the cholesterol transporter ABCA1, potentially via the AKT pathway. Together, our results indicate that bone marrow-derived α-SMA+ macrophages contribute to atherosclerotic plaque formation due to dysregulated cholesterol uptake and efflux, providing potential targets for the prevention and treatment of atherosclerosis.

Ferroptosis: a potential therapeutic target in cardio-cerebrovascular diseases

Cardio-cerebrovascular diseases (CCVDs) are the leading cause of global mortality, yet effective treatment options remain limited. Ferroptosis, a novel form of regulated cell death, has emerged as a critical player in various CCVDs, including atherosclerosis, myocardial infarction, ischemia-reperfusion injury, cardiomyopathy, and ischemic/hemorrhagic strokes. This review highlights the core mechanisms of ferroptosis, its pathological implications in CCVDs, and the therapeutic potential of targeting this process. Additionally, it explores the role of Chinese herbal medicines (CHMs) in mitigating ferroptosis, offering novel therapeutic strategies for CCVDs management. Ferroptosis is regulated by several key pathways. The GPX4-GSH-System Xc- axis is central to ferroptosis execution, involving GPX4 using GSH to neutralize lipid peroxides, with system Xc- being crucial for GSH synthesis. The NAD(P)H/FSP1/CoQ10 axis involves FSP1 regenerating CoQ10 via NAD(P)H, inhibiting lipid peroxidation independently of GPX4. Lipid peroxidation, driven by PUFAs and enzymes like ACSL4 and LPCAT3, and iron metabolism, regulated by proteins like TfR1 and ferritin, are also crucial for ferroptosis. Inhibiting ferroptosis shows promise in managing CCVDs. In atherosclerosis, ferroptosis inhibitors reduce iron accumulation and lipid peroxidation. In myocardial infarction, inhibitors protect cardiomyocytes by preserving GPX4 and SLC7A11 levels. In ischemia-reperfusion injury, targeting ferroptosis reduces myocardial and cerebral damage. In diabetic cardiomyopathy, Nrf2 activators alleviate oxidative stress and iron metabolism irregularities. CHMs offer natural compounds that mitigate ferroptosis. They possess antioxidant properties, chelate iron, and modulate signaling pathways like Nrf2 and AMPK. For example, Salvia miltiorrhiza and Astragalus membranaceus reduce oxidative stress, while some CHMs chelate iron, reducing its availability for ferroptosis. In conclusion, ferroptosis plays a pivotal role in CCVDs, and targeting it offers novel therapeutic avenues. CHMs show promise in reducing ferroptosis and improving patient outcomes. Future research should explore combination therapies and further elucidate the molecular interactions in ferroptosis.

The role of Morin in attenuating atherosclerosis via STAT1 pathway inhibition

Atherosclerotic cardiovascular diseases can lead to myocardial infarction and stroke, which are linked to elevated rates of mortality. Morin is a flavonoid compound that can be extracted from mulberries and possesses anti-inflammatory and antioxidant properties. The objective of this research is to elucidate Morin's impact on atherosclerosis. The ApoE-/- mice were divided into three groups: control group, HFD group and HFD + Morin group. The mice in control group received a normal diet (ND). To create an atherosclerosis model, ApoE-/- mice were subjected to a high-fat diet (HFD) for 8 weeks. The mice were assigned to two distinct categories at random based on whether Morin intervention was administered: one serving as the HFD group and the other as the HFD + Morin group. The mice received Morin for 4 weeks at a dosage of 50 mg/kg orally in the model + Morin group. Subsequently, ORO staining assay was performed to evaluate the formation of aortic plaques. ELISA was used to measure IFN-γ and TNF-α levels in plasma of the mice. In vitro, mouse macrophages RAW264.7 were cultured and treated with IFN-γ for 24 h, followed by Morin treatment for another 24 h. Western blotting was conducted to analyze changes in macrophage polarization markers CD86 and CD206, as well as P-STAT1 levels. DCFH-DA was used to detect changes in intracellular ROS levels. Subsequently, RAW264.7 cells were treated with the STAT1 inhibitor Lenvatinib to further investigate changes in CD86 and CD206, as well as ROS levels. In vivo data showed that Morin markedly diminished the size of aortic plaques and suppressed the secretion of IFN-γ and TNF-α. In vitro data indicated that Morin reduced M1 polarization and intracellular ROS levels through inhibiting the STAT1 pathway activation in RAW264.7 cells, ultimately suppressing inflammation.

Tissue macrophages: origin, heterogenity, biological functions, diseases and therapeutic targets

Macrophages are immune cells belonging to the mononuclear phagocyte system. They play crucial roles in immune defense, surveillance, and homeostasis. This review systematically discusses the types of hematopoietic progenitors that give rise to macrophages, including primitive hematopoietic progenitors, erythro-myeloid progenitors, and hematopoietic stem cells. These progenitors have distinct genetic backgrounds and developmental processes. Accordingly, macrophages exhibit complex and diverse functions in the body, including phagocytosis and clearance of cellular debris, antigen presentation, and immune response, regulation of inflammation and cytokine production, tissue remodeling and repair, and multi-level regulatory signaling pathways/crosstalk involved in homeostasis and physiology. Besides, tumor-associated macrophages are a key component of the TME, exhibiting both anti-tumor and pro-tumor properties. Furthermore, the functional status of macrophages is closely linked to the development of various diseases, including cancer, autoimmune disorders, cardiovascular disease, neurodegenerative diseases, metabolic conditions, and trauma. Targeting macrophages has emerged as a promising therapeutic strategy in these contexts. Clinical trials of macrophage-based targeted drugs, macrophage-based immunotherapies, and nanoparticle-based therapy were comprehensively summarized. Potential challenges and future directions in targeting macrophages have also been discussed. Overall, our review highlights the significance of this versatile immune cell in human health and disease, which is expected to inform future research and clinical practice.

The Crosstalk Between Endothelial Cells, Smooth Muscle Cells, and Macrophages in Atherosclerosis

Atherosclerosis (AS) is a chronic inflammatory vascular disease closely tied to cellular metabolism. Recent genome-wide association study data have suggested the significant roles of endothelial cells, smooth muscle cells, and macrophages in the regression and exacerbation of AS. However, the impact of cellular crosstalk and cellular metabolic derangements on disease progression in AS is vaguely understood. In this review, we analyze the roles of the three cell types in AS. We also summarize the crosstalk between the two of them, and the associated molecules and consequences involved. In addition, we emphasize potential therapeutic targets and highlight the importance of the three-cell co-culture model and extracellular vesicles in AS-related research, providing ideas for future studies.

Predicting plaque regression based on plaque characteristics identified by optical coherence tomography: A retrospective study

BACKGROUND

Atherosclerosis is a lipid-driven, systemic immune-inflammatory disease characterized by the accumulation of plaque within the arterial walls. Plaque regression can occur following appropriate treatment interventions. Optical coherence tomography (OCT), a high-resolution imaging modality, is frequently employed to assess plaque morphology. This study aims to explore the correlation between plaque characteristics identified using OCT, particularly macrophage infiltration, and subsequent plaque regression.

METHODS

In this retrospective study, data from 112 individuals with coronary artery plaques, who underwent OCT imaging at our hospital, between June 2019 and June 2024, were evaluated. Plaques were classified as lipid-rich, fibrous, or calcified based on the initial OCT findings. Macrophage infiltration levels within each plaque type were quantified. After one year of follow-up, repeat OCT imaging was performed to evaluate plaque regression. Statistical analyses were conducted to assess the relationship between initial plaque characteristics and regression outcomes.

RESULTS

Plaques that underwent regression were more commonly lipid-rich and exhibited higher levels of macrophage infiltration compared to those without regression. Multivariate analysis identified the histological inflammation score (HIS) as an independent factor influencing plaque regression.

CONCLUSION

Macrophage-rich plaques, as detected by OCT, are significant predictors of plaque regression. The identification of vulnerable plaque features through OCT can enhance the early diagnosis and treatment strategies for atherosclerotic cardiovascular disease.

Efferocytosis: A new star of atherosclerotic plaques reversal

Efferocytosis is considered the key to eliminate apoptotic cells (ACs) under physiological and pathological conditions in vivo, mainly through different types of macrophages to achieve this process. Especially, tissue-resident macrophages (TRMs) are very significant for inflammation regression and maintenance of homeostasis in vivo. Abnormal efferocytosis will lead to the accumulation of ACs and the release of a variety of pro-inflammatory factors, which mediates the occurrence of many inflammatory diseases, including atherosclerosis (AS). AS is a chronic inflammatory vascular disease with the participation of the immune system. Defective efferocytosis will accelerate the progress of AS to a certain extent. Therefore, it is of great significance to understand the mechanism of efferocytosis and realize the prevention and treatment of AS through efferocytosis. In this review, we will briefly describe the specific process of efferocytosis, deeply discuss the possible molecular mechanism of impaired efferocytosis promoting the development of AS, and summarize the ways to prevent and treat AS through efferocytosis intervention therapy.

Extracellular Matrix-Mimicking Hydrogel with Angiogenic and Immunomodulatory Properties Accelerates Healing of Diabetic Wounds by Promoting Autophagy

The management of diabetic wounds faces significant challenges due to the excessive activation of reactive oxygen species (ROS), dysregulation of the inflammatory response, and impaired angiogenesis. A substantial body of evidence suggests that the aforementioned diverse factors contributing to the delayed healing of diabetic wounds may be associated with impaired autophagy. Impaired autophagy leads to endothelial and fibroblast dysfunction and impedes macrophage phenotypic transformation. This disruption hinders angiogenesis and extracellular matrix deposition, ultimately culminating in delayed wound healing. Therefore, biomaterials possessing autophagy regulatory functions hold significant potential for clinical applications in enhancing the healing of diabetic wounds. A hybrid multifunctional hydrogel (GelMa@SIS-Qu) has been developed, comprising methacrylamide gelatin (GelMa), a small intestine submucosal acellular matrix (SIS), and quercetin nanoparticles, which demonstrates the capability to promote autophagy. The promotion of autophagy not only reduces ROS levels in endothelial cells and enhances their antioxidant activity but also mitigates ROS-induced endothelial cell dysfunction and apoptosis, thereby promoting angiogenesis. Furthermore, the promotion of autophagy facilitates the phenotypic transformation of macrophages from the M1 phenotype to the M2 phenotype. This study investigates the distinctive mechanisms of the GelMa@SIS-Qu hydrogel and proposes a promising therapeutic strategy for treating diabetes-related wounds.

cRGD-platelet@MnO/MSN@PPARα/LXRα Nanoparticles Improve Atherosclerosis in Rats by Inhibiting Inflammation and Reducing Blood Lipid

OBJECTIVE

Atherosclerosis (AS) is an inflammatory disease of arterial intima driven by lipids. Liver X receptor alpha (LXRα) and peroxisome proliferator-activated receptor alpha (PPARα) agonists are limited in the treatment of AS due to their off-target effects and serious side effects. Therefore, this study was designed to construct a novel nanoparticle (NP) and evaluate its mechanism of action on inflammation inhibition and lipid reduction in AS.

METHODS

We synthesized cRGD-platelet@MnO/MSN@PPARα/LXRα NPs (cRGD-platelet- NPs) and confirmed their size, safety, and targeting ability through various tests, including dynamic light scattering and immunofluorescence. In vivo and in vitro experiments assessed cell proliferation, apoptosis, inflammation, and plaque formation. Finally, the NF-κB signaling pathway expression in rat aorta was determined using a western blot.

RESULTS

The synthesis of cRGD-platelet-NPs was successful; the particle size was approximately 150 nm, and the PDI was below 0.3. They could be successfully absorbed by cells, exhibiting high safety in vivo and in vitro. The cRGD-platelet-NPs successfully reduced plaque formation, improved lipid profiles by lowering LDL-cholesterol, total cholesterol, and triglycerides, and raised HDL-cholesterol levels. Additionally, they decreased inflammatory markers in the serum and aortic tissue, suggesting reduced inflammation. Immunohistochemistry and western blot analyses indicated that these NPs could not only promote M2 macrophage polarization but also suppress the NF-κB signaling pathway.

CONCLUSION

The newly developed cRGD-platelet-NPs with high safety are a promising approach to AS treatment, which can regulate ABCA1, reduce the formation of AS plaques, and enhance cholesterol efflux. The mechanism may involve the suppression of the NF-κB signaling pathway.

Atheroprotective role of vinpocetine: an old drug with new indication

Endothelial dysfunction is considered one of the main causes of atherosclerosis and elevated blood pressure. Atherosclerosis (AS) formation is enhanced by different mechanisms including cytokine generation, vascular smooth muscle cell proliferation, and migration. One of the recent treatment toward endothelial dysfunction is vinpocetine (VPN). VPN is an ethyl apovincaminate used in the management of different cerebrovascular disorders and endothelial dysfunction through inhibition of atherosclerosis formation. VPN is a potent inhibitor of phosphodiesterase enzyme 1 (PDE1) as well it has anti-inflammatory and antioxidant effects through inhibition of the expression of nuclear factor kappa B (NF-κB). VPN has been shown to be effective against development and progression of AS. However, the underlying molecular mechanism was not fully clarified. Consequently, objective of the present narrative review was to clarify the mechanistic role of VPN in AS. Most of pro-inflammatory cytokines released from macrophages are inhibited by the action of VPN via NF-κB-dependent mechanism. VPN blocks monocyte adhesion and migration by inhibiting the expression of pro-inflammatory cytokines. As well, VPN is effective in reducing oxidative stress, a cornerstone in the pathogenesis of AS, through inhibition of NF-κB and PDE1. VPN promotes plaque stability and prevent erosion and rupture of atherosclerotic plaque. In conclusion, VPN through mitigation of inflammatory and oxidative stress with plaque stability effects could be effective agent in the management of endothelial dysfunction through inhibition of atherosclerosis mediators.

HDL Cholesterol-Associated Shifts in the Expression of Preselected Genes Reveal both Pro-Atherogenic and Atheroprotective Effects of HDL in Coronary Artery Disease

BACKGROUND

The associations of high-density lipoprotein (HDL) level and functionality with lipid metabolism, inflammation, and innate immunity in coronary artery disease (CAD) remain controversial. The differential expression of a set of genes related to HDL metabolism (24 genes) and atherogenesis (41 genes) in peripheral blood mononuclear cells (PBMC) from CAD and control patients with varied HDL cholesterol (HDL-C) levels was compared.

METHODS

76 male patients 40-60 years old with CAD diagnosed by angiography and 63 control patients were divided into three groups with low, normal (1.0-1.4 mM), and increased HDL-C levels. Transcript levels were measured by real-time PCR. The differentially expressed genes (DEGs) and associated metabolic pathways were analyzed for three groups, with prevalent CAD as an outcome.

RESULTS

The common feature was the increased odds ratio values for liver X receptor (LXR) gene expression for three patient groups. CAD patients with low HDL-C possessed 24 DEGs with lower expression of genes involved in cholesterol efflux, and down-regulated SREBF1 and ABCG1 are suggested as gene signatures. CAD patients with normal HDL-C possessed nine DEGs with down-regulated ITGAM and ALB as gene signatures. CAD patients with increased HDL-C possessed 19 DEGs with down-regulated APOA1 and HMGCR as gene signatures. With gene expression signatures, one standard deviation higher average gene expressions were associated with 5.1-, 48.8-, and 38.9-fold fewer CAD cases for three patient groups. As HDL-C increased in CAD patients, the expression of ABCG1, CUBN, and HDLBP genes increased, while the expression of HMGCR and NPC2 genes, involved in cholesterol synthesis and trafficking, decreased. The expression of CD14, CD36, S100A8, S100A9, S100A12, TLR5, TLR8, and VEGFA genes, involved in angiogenesis and inflammation mainly via nuclear factor-κB (NF-κB), decreased.

CONCLUSIONS

The increased accumulation of cholesteryl ester in PBMC from patients with low HDL-C was suggested. This assumption contrasts with the suggested accumulation of free cholesterol in PBMC from patients with increased HDL-C, concomitant with suppression of cholesterol synthesis and traffic to the plasma membrane, and with an inflammatory state controlled by depressed CD36-mediated and upregulated apoE-mediated immunometabolic signaling. Gene signatures may be used for the diagnosis, prognosis, and treatment of CAD in dependence on HDL-C levels.

Defective macrophage efferocytosis in advanced atherosclerotic plaque and mitochondrial therapy

Atherosclerosis (AS) is a chronic inflammatory disease primarily affecting large and medium-sized arterial vessels, characterized by lipoprotein disorders, intimal thickening, smooth muscle cell proliferation, and the formation of vulnerable plaques. Macrophages (MΦs) play a vital role in the inflammatory response throughout all stages of atherosclerotic development and are considered significant therapeutic targets. In early lesions, macrophage efferocytosis rapidly eliminates harmful cells. However, impaired efferocytosis in advanced plaques perpetuates the inflammatory microenvironment of AS. Defective efferocytosis has emerged as a key factor in atherosclerotic pathogenesis and the progression to severe cardiovascular disease. Herein, this review probes into investigate the potential mechanisms at the cellular, molecular, and organelle levels underlying defective macrophage efferocytosis in advanced lesion plaques. In the inflammatory microenvironments of AS with interactions among diverse inflammatory immune cells, impaired macrophage efferocytosis is strongly linked to multiple factors, such as a lower absolute number of phagocytes, the aberrant expression of crucial molecules, and impaired mitochondrial energy provision in phagocytes. Thus, focusing on molecular targets to enhance macrophage efferocytosis or targeting mitochondrial therapy to restore macrophage metabolism homeostasis has emerged as a potential strategy to mitigate the progression of advanced atherosclerotic plaque, providing various treatment options.

Atherosis-associated lnc_000048 activates PKR to enhance STAT1-mediated polarization of THP-1 macrophages to M1 phenotype

JOURNAL/nrgr/04.03/01300535-202419110-00029/figure1/v/2024-03-08T184507Z/r/image-tiff Our previous study has demonstrated that lnc_000048 is upregulated in large-artery atherosclerotic stroke and promotes atherosclerosis in ApoE-/- mice. However, little is known about the role of lnc_000048 in classically activated macrophage (M1) polarization. In this study, we established THP-1-derived testing state macrophages (M0), M1 macrophages, and alternately activated macrophages (M2). Real-time fluorescence quantitative PCR was used to verify the expression of marker genes and the expression of lnc_000048 in macrophages. Flow cytometry was used to detect phenotypic proteins (CD11b, CD38, CD80). We generated cell lines with lentivirus-mediated upregulation or downregulation of lnc_000048. Flow cytometry, western blot, and real-time fluorescence quantitative PCR results showed that down-regulation of lnc_000048 reduced M1 macrophage polarization and the inflammation response, while over-expression of lnc_000048 led to the opposite effect. Western blot results indicated that lnc_000048 enhanced the activation of the STAT1 pathway and mediated the M1 macrophage polarization. Moreover, catRAPID prediction, RNA-pull down, and mass spectrometry were used to identify and screen the protein kinase RNA-activated (PKR), then catRAPID and RPIseq were used to predict the binding ability of lnc_000048 to PKR. Immunofluorescence (IF)-RNA fluorescence in situ hybridization (FISH) double labeling was performed to verify the subcellular colocalization of lnc_000048 and PKR in the cytoplasm of M1 macrophage. We speculate that lnc_000048 may form stem-loop structure-specific binding and activate PKR by inducing its phosphorylation, leading to activation of STAT1 phosphorylation and thereby enhancing STAT1 pathway-mediated polarization of THP-1 macrophages to M1 and inflammatory factor expression. Taken together, these results reveal that the lnc_000048/PKR/STAT1 axis plays a crucial role in the polarization of M1 macrophages and may be a novel therapeutic target for atherosclerosis alleviation in stroke.

A Macrophage Membrane-Functionalized, Reactive Oxygen Species-Activatable Nanoprodrug to Alleviate Inflammation and Improve the Lipid Metabolism for Atherosclerosis Management

Atherosclerosis (AS) management typically relies on therapeutic drug interventions, but these strategies typically have drawbacks, including poor site specificity, high systemic intake, and undesired side effects. The field of cell membrane camouflaged biomimetic nanomedicine offers the potential to address these challenges thanks to its ability to mimic the natural properties of cell membranes that enable enhanced biocompatibility, prolonged blood circulation, targeted drug delivery, and evasion of immune recognition, ultimately leading to improved therapeutic outcomes and reduced side effects. In this study, a novel biomimetic approach is developed to construct the M1 macrophage membrane-coated nanoprodrug (MM@CD-PBA-RVT) for AS management. The advanced MM@CD-PBA-RVT nanotherapeutics are proved to be effective in inhibiting macrophage phagocytosis and facilitating the cargo delivery to the activated endothelial cells of AS lesion both in vitro and in vivo. Over the 30-day period of nanotherapy, MM@CD-PBA-RVT is capable of significantly inhibiting the progression of AS, while also maintaining a favorable safety profile. In conclusion, the biomimetic MM@CD-PBA-RVT shows promise as feasible drug delivery systems for safe and effective anti-AS applications.

Lipid nanoparticles encapsulating curcumin for imaging and stabilization of vulnerable atherosclerotic plaques via phagocytic "eat-me" signals

Curcumin potentiates the stabilization of atherosclerotic plaques by polarizing macrophages, but its non-specific targeting hinders its clinical application. We aim to harness multifunctional lipid nanoparticles (MLNPs) to facilitate the imaging and targeted delivery of curcumin specifically to inflammatory macrophages, counteracting vulnerable plaques and mitigating the risk of ischemic events. Cholesteryl-9-carboxynonanoate-(125I‑iron oxide nanoparticle/Curcumin)-lipid-coated nanoparticles [9-CCN-(125I-ION/Cur)-LNPs], namely MLNPs, are designed to carry hybrid imaging agents. These agents combine 125I-ION with lipids containing phagocytic 'eat-me' signals, inducing macrophages to engulf the MLNPs. Our research demonstrates that the designed MLNPs accurately accumulate at unstable plaques and are precisely visualized and highlighted by both SPECT and MRI. Furthermore, MLNPs achieve high efficiency in delivering 125I-ION and curcumin to macrophages, ultimately leading to significant M1-to-M2 macrophage polarization. These real-time imaging and polarization capabilities of plaques have immediate clinical applicability and may pave the way for novel therapies to stabilize unstable atherosclerotic plaques.

Macrophages in vascular disease: Roles of mitochondria and metabolic mechanisms

Macrophages are a dynamic cell type of the immune system implicated in the pathophysiology of vascular diseases and are a major contributor to pathological inflammation. Excessive macrophage accumulation, activation, and polarization is observed in aortic aneurysm (AA), atherosclerosis, and pulmonary arterial hypertension. In general, macrophages become activated and polarized to a pro-inflammatory phenotype, which dramatically changes cell behavior to become pro-inflammatory and infiltrative. These cell types become cumbersome and fail to be cleared by normal mechanisms such as autophagy. The result is a hyper-inflammatory environment causing the recruitment of adjacent cells and circulating immune cells to further augment the inflammatory response. In AA, this leads to excessive ECM degradation and chemokine secretion, ultimately causing macrophages to dominate the immune cell landscape in the aortic wall. In atherosclerosis, monocytes are recruited to the vascular wall, where they polarize to the pro-inflammatory phenotype and induce inflammatory pathway activation. This leads to the development of foam cells, which significantly contribute to neointima and necrotic core formation in atherosclerotic plaques. Pro-inflammatory macrophages, which affect other vascular diseases, present with fragmented mitochondria and corresponding metabolic dysfunction. Targeting macrophage mitochondrial dynamics has proved to be an exciting potential therapeutic approach to combat vascular disease. This review will summarize mitochondrial and metabolic mechanisms of macrophage activation, polarization, and accumulation in vascular diseases.

Comprehensive analysis of shared risk genes and immunity-metabolisms between non-alcoholic fatty liver disease and atherosclerosis via bulk and single-cell transcriptome analyses

Objective

and design: Considering the clinical link between non-alcoholic fatty liver disease (NAFLD) and atherosclerosis (AS), we performed bioinformatics analysis to uncover their pathogenic interrelationship.

Methods and results

Data from the U.S. National Health and Nutritional Examination Survey (NHANES) 1999-2018 were included. Among 4851 participants in NHANES, NAFLD was significantly associated with atherosclerotic cardiovascular disease risk (ASCVD risk) (OR = 2.32, 95%CI: 2.04-2.65, P < 0.0001). We conducted WGCNA analysis for NAFLD (GSE130970) and AS (GSE28829) and identified three modules positively related to NAFLD severity and two modules accelerating atherosclerosis plaque progression. 198 key-modules genes were obtained via overlapping these modules. Next, we mined the disease-controlled differentially expressed genes (DEGs) from NAFLD (GSE89632) and AS (GSE100927), respectively. The final common risk genes (ACP5, TP53I3, RPS6KA1, TYMS, TREM2, CA12, and IFI27) were defined by intersecting the upregulated DEGs with 198 genes and validated in new datasets (GSE48452 and GSE43292). Importantly, they showed good diagnostic ability for NAFLD and AS. Immune infiltration analysis showed both illnesses have dysregulated immunity. Analysis of single-cell sequencing datasets NAFLD (GSE179886) and AS (GSE159677) uncovered different abnormal expressions of seven common genes in different immune cells while highlighting metabolic disturbances including upregulation of fatty acid biosynthesis, downregulation of fatty acid degradation and elongation.

Conclusion

We found 7 shared hub genes with good diagnostic ability and depicted the landscapes of immune and metabolism involved in NAFLD and AS. Our results provided a comprehensive association between them and may contribute to developing potential intervention strategies for targeting both disorders based on these risk factors.

T-Cell Metabolic Reprogramming in Atherosclerosis

Atherosclerosis is a key pathological basis for cardiovascular diseases, significantly influenced by T-cell-mediated immune responses. T-cells differentiate into various subtypes, such as pro-inflammatory Th1/Th17 and anti-inflammatory Th2/Treg cells. The imbalance between these subtypes is critical for the progression of atherosclerosis (AS). Recent studies indicate that metabolic reprogramming within various microenvironments can shift T-cell differentiation towards pro-inflammatory or anti-inflammatory phenotypes, thus influencing AS progression. This review examines the roles of pro-inflammatory and anti-inflammatory T-cells in atherosclerosis, focusing on how their metabolic reprogramming regulates AS progression and the associated molecular mechanisms of mTOR and AMPK signaling pathways.

Moving from lipids to leukocytes: inflammation and immune cells in atherosclerosis

Atherosclerotic cardiovascular disease (ASCVD) is the most important cause of morbidity and mortality worldwide. While it is traditionally attributed to lipid accumulation in the vascular endothelium, recent research has shown that plaque inflammation is an important additional driver of atherogenesis. Though clinical outcome trials utilizing anti-inflammatory agents have proven promising in terms of reducing ASCVD risk, it is imperative to identify novel actionable targets that are more specific to atherosclerosis to mitigate adverse effects associated with systemic immune suppression. To that end, this review explores the contributions of various immune cells from the innate and adaptive immune system in promoting and mitigating atherosclerosis by integrating findings from experimental studies, high-throughput multi-omics technologies, and epidemiological research.

Emerging Trends and Innovations in the Treatment and Diagnosis of Atherosclerosis and Cardiovascular Disease: A Comprehensive Review towards Healthier Aging

Cardiovascular diseases (CVDs) are classed as diseases of aging, which are associated with an increased prevalence of atherosclerotic lesion formation caused by such diseases and is considered as one of the leading causes of death globally, representing a severe health crisis affecting the heart and blood vessels. Atherosclerosis is described as a chronic condition that can lead to myocardial infarction, ischemic cardiomyopathy, stroke, and peripheral arterial disease and to date, most pharmacological therapies mainly aim to control risk factors in patients with cardiovascular disease. Advances in transformative therapies and imaging diagnostics agents could shape the clinical applications of such approaches, including nanomedicine, biomaterials, immunotherapy, cell therapy, and gene therapy, which are emerging and likely to significantly impact CVD management in the coming decade. This review summarizes the current anti-atherosclerotic therapies' major milestones, strengths, and limitations. It provides an overview of the recent discoveries and emerging technologies in nanomedicine, cell therapy, and gene and immune therapeutics that can revolutionize CVD clinical practice by steering it toward precision medicine. CVD-related clinical trials and promising pre-clinical strategies that would significantly impact patients with CVD are discussed. Here, we review these recent advances, highlighting key clinical opportunities in the rapidly emerging field of CVD medicine.

Loss of Bcl-3 regulates macrophage polarization by promoting macrophage glycolysis

M1/M2 macrophage polarization plays an important role in regulating the balance of the microenvironment within tissues. Moreover, macrophage polarization involves the reprogramming of metabolism, such as glucose and lipid metabolism. Transcriptional coactivator B-cell lymphoma-3 (Bcl-3) is an atypical member of the IκB family that controls inflammatory factor levels in macrophages by regulating nuclear factor kappa B pathway activation. However, the relationship between Bcl-3 and macrophage polarization and metabolism remains unclear. In this study, we show that the knockdown of Bcl-3 in macrophages can regulate glycolysis-related gene expression by promoting the activation of the nuclear factor kappa B pathway. Furthermore, the loss of Bcl-3 was able to promote the interferon gamma/lipopolysaccharide-induced M1 macrophage polarization by accelerating glycolysis. Taken together, these results suggest that Bcl-3 may be a candidate gene for regulating M1 polarization in macrophages.

Resolution of inflammation, an active process to restore the immune microenvironment balance: A novel drug target for treating arterial hypertension

The resolution of inflammation, the other side of the inflammatory response, is defined as an active and highly coordinated process that promotes the restoration of immune microenvironment balance and tissue repair. Inflammation resolution involves several key processes, including dampening proinflammatory signaling, specialized proresolving lipid mediator (SPM) production, nonlipid proresolving mediator production, efferocytosis and regulatory T-cell (Treg) induction. In recent years, increasing attention has been given to the effects of inflammation resolution on hypertension. Furthermore, our previous studies reported the antihypertensive effects of SPMs. Therefore, in this review, we aim to summarize and discuss the detailed association between arterial hypertension and inflammation resolution. Additional, the association between gut microbe-mediated immune and hypertension is discussed. This findings suggested that accelerating the resolution of inflammation can have beneficial effects on hypertension and its related organ damage. Exploring novel drug targets by focusing on various pathways involved in accelerating inflammation resolution will contribute to the treatment and control of hypertensive diseases in the future.

Pharmacological characterization of the antidiabetic drug metformin in atherosclerosis inhibition: A comprehensive insight

BACKGROUND

Atherosclerosis (AS) is a progressive disease that interferes with blood flow, leading to cardiovascular complications such as hypertension, ischemic heart disease, ischemic stroke, and vascular ischemia. The progression of AS is correlated with inflammation, oxidative stress, and endothelial dysfunction. Various signaling pathways, like nuclear erythroid-related factor 2 (Nrf2) and Kruppel-like factor 2 (KLF2), are involved in the pathogenesis of AS. Nrf2 and KLF2 have anti-inflammatory and antioxidant properties. Thus, activation of these pathways may reduce the development of AS. Metformin, an insulin-sensitizing drug used in the management of type 2 diabetes mellitus (T2DM), increases the expression of Nrf2 and KLF2. AS is a common long-term macrovascular complication of T2DM. Thus, metformin, through its pleiotropic anti-inflammatory effect, may attenuate the development and progression of AS.

AIMS

Therefore, this review aims to investigate the possible role of metformin in AS concerning its effect on Nrf2 and KLF2 and inhibition of reactive oxygen species (ROS) formation. In addition to its antidiabetic effect, metformin can reduce cardiovascular morbidities and mortalities compared to other antidiabetic agents, even with similar blood glucose control by the Nrf2/KLF2 pathway activation.

CONCLUSION

In conclusion, metformin is an effective therapeutic strategy against the development and progression of AS, mainly through activation of the KLF2/Nrf2 axis.

Possible role of LCZ696 in atherosclerosis: new inroads and perspective

LCZ696 blocks both angiotensin receptor type 1 (ATR1) and neprilysin (NEP), which are intricate in the degradation of natriuretic peptides (NPs) and other endogenous peptides. It has been shown NEP inhibitors and LCZ696 could be effectively in the management of atherosclerosis (AS). However, the underlying mechanism of LCZ696 in AS is needed to be clarified entirely. Hence, this review is directed to reconnoiter the mechanistic role of LCZ696 in AS. The anti-inflammatory role of LCZ696 is related to the inhibition of transforming growth factor beta (TGF-β)-activated kinase 1 (TAK) and nod-like receptor pyrin 3 receptor (NLRP3) inflammasome. Moreover, LCZ696, via inhibition of pro-inflammatory cytokines, oxidative stress, apoptosis and endothelial dysfunction can attenuate the development and progression of AS. In conclusion, LCZ696 could be effective in the management of AS through modulation of inflammatory and oxidative signaling. Preclinical and clinical studies are recommended in this regard.

NLRP3 inflammasome in atherosclerosis: Mechanisms and targeted therapies

Atherosclerosis (AS) is the primary pathology behind various cardiovascular diseases and the leading cause of death and disability globally. Recent evidence suggests that AS is a chronic vascular inflammatory disease caused by multiple factors. In this context, the NLRP3 inflammasome, acting as a signal transducer of the immune system, plays a critical role in the onset and progression of AS. The NLRP3 inflammasome is involved in endothelial injury, foam cell formation, and pyroptosis in AS. Therefore, targeting the NLRP3 inflammasome offers a new treatment strategy for AS. This review highlights the latest insights into AS pathogenesis and the pharmacological therapies targeting the NLRP3 inflammasome, focusing on optimal targets for small molecule inhibitors. These insights are valuable for rational drug design and the pharmacological assessment of new targeted NLRP3 inflammasome inhibitors in treating AS.

JAK Inhibitors in Rheumatoid Arthritis: Immunomodulatory Properties and Clinical Efficacy

Rheumatoid arthritis (RA) is a highly prevalent autoimmune disorder. The pathogenesis of the disease is complex and involves various cellular populations, including fibroblast-like synoviocytes, macrophages, and T cells, among others. Identification of signalling pathways and molecules that actively contribute to the development of the disease is crucial to understanding the mechanisms involved in the chronic inflammatory environment present in affected joints. Recent studies have demonstrated that the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway regulates the behaviour of immune cells and contributes to the progression of RA. Several JAK inhibitors, such as tofacitinib, baricitinib, upadacitinib, and filgocitinib, have been developed, and their efficacy and safety in patients with RA have been comprehensively investigated in a number of clinical trials. Consequently, JAK inhibitors have been approved and registered as a treatment for patients with RA. In this review, we discuss the involvement of JAK/STAT signalling in the pathogenesis of RA and summarise the potential beneficial effects of JAK inhibitors in cells implicated in the pathogenesis of the disease. Moreover, we present the most important phase 3 clinical trials that evaluated the use of these agents in patients.

CD163+ Macrophages Induce Endothelial-to-Mesenchymal Transition in Atheroma

BACKGROUND

Cell phenotype switching is increasingly being recognized in atherosclerosis. However, our understanding of the exact stimuli for such cellular transformations and their significance for human atherosclerosis is still evolving. Intraplaque hemorrhage is thought to be a major contributor to plaque progression in part by stimulating the influx of CD163+ macrophages. Here, we explored the hypothesis that CD163+ macrophages cause plaque progression through the induction of proapoptotic endothelial-to-mesenchymal transition (EndMT) within the fibrous cap.

METHODS

Human coronary artery sections from CVPath's autopsy registry were selected for pathological analysis. Athero-prone ApoE-/- and ApoE-/-/CD163-/- mice were used for in vivo studies. Human peripheral blood mononuclear cell-induced macrophages and human aortic endothelial cells were used for in vitro experiments.

RESULTS

In 107 lesions with acute coronary plaque rupture, 55% had pathological evidence of intraplaque hemorrhage in nonculprit vessels/lesions. Thinner fibrous cap, greater CD163+ macrophage accumulation, and a larger number of CD31/FSP-1 (fibroblast specific protein-1) double-positive cells and TUNEL (terminal deoxynucleotidyl transferase-dUTP nick end labeling) positive cells in the fibrous cap were observed in nonculprit intraplaque hemorrhage lesions, as well as in culprit rupture sections versus nonculprit fibroatheroma sections. Human aortic endothelial cells cultured with supernatants from hemoglobin/haptoglobin-exposed macrophages showed that increased mesenchymal marker proteins (transgelin and FSP-1) while endothelial markers (VE-cadherin and CD31) were reduced, suggesting EndMT induction. Activation of NF-κB (nuclear factor kappa β) signaling by proinflammatory cytokines released from CD163+ macrophages directly regulated the expression of Snail, a critical transcription factor during EndMT induction. Western blot analysis for cleaved caspase-3 and microarray analysis of human aortic endothelial cells indicated that apoptosis was stimulated during CD163+ macrophage-induced EndMT. Additionally, CD163 deletion in athero-prone mice suggested that CD163 is required for EndMT and plaque progression. Using single-cell RNA sequencing from human carotid endarterectomy lesions, a population of EndMT was detected, which demonstrated significant upregulation of apoptosis-related genes.

CONCLUSIONS

CD163+ macrophages provoke EndMT, which may promote plaque progression through fibrous cap thinning.

Targeting macrophages with multifunctional nanoparticles to detect and prevent atherosclerotic cardiovascular disease

Despite the emergence of novel diagnostic, pharmacological, interventional, and prevention strategies, atherosclerotic cardiovascular disease remains a significant cause of morbidity and mortality. Nanoparticle (NP)-based platforms encompass diverse imaging, delivery, and pharmacological properties that provide novel opportunities for refining diagnostic and therapeutic interventions for atherosclerosis at the cellular and molecular levels. Macrophages play a critical role in atherosclerosis and therefore represent an important disease-related diagnostic and therapeutic target, especially given their inherent ability for passive and active NP uptake. In this review, we discuss an array of inorganic, carbon-based, and lipid-based NPs that provide magnetic, radiographic, and fluorescent imaging capabilities for a range of highly promising research and clinical applications in atherosclerosis. We discuss the design of NPs that target a range of macrophage-related functions such as lipoprotein oxidation, cholesterol efflux, vascular inflammation, and defective efferocytosis. We also provide examples of NP systems that were developed for other pathologies such as cancer and highlight their potential for repurposing in cardiovascular disease. Finally, we discuss the current state of play and the future of theranostic NPs. Whilst this is not without its challenges, the array of multifunctional capabilities that are possible in NP design ensures they will be part of the next frontier of exciting new therapies that simultaneously improve the accuracy of plaque diagnosis and more effectively reduce atherosclerosis with limited side effects.

Curcumin Equipped Nanozyme-Like Metal-Organic Framework Platform for the Targeted Atherosclerosis Treatment with Lipid Regulation and Enhanced Magnetic Resonance Imaging Capability

Atherosclerotic cardiovascular disease (ASCVD) has become the leading cause of death worldwide, and early diagnosis and treatment of atherosclerosis (AS) are crucial for reducing the occurrence of acute cardiovascular events. However, early diagnosis of AS is challenging, and oral anti-AS drugs suffer from limitations like imprecise targeting and low bioavailability. To overcome the aforementioned shortcomings, Cur/MOF@DS is developed, a nanoplatform integrating diagnosis and treatment by loading curcumin (Cur) into metal-organic frameworks with nanozymes and magnetic resonance imaging (MRI) properties. In addition, the surface-modification of dextran sulfate (DS) enables PCN-222(Mn) effectively target scavenger receptor class A in macrophages or foam cells within the plaque region. This nanoplatform employs mechanisms that effectively scavenge excessive reactive oxygen species in the plaque microenvironment, promote macrophage autophagy and regulate macrophage polarization to realize lipid regulation. In vivo and in vitro experiments confirm that this nanoplatform has outstanding MRI performance and anti-AS effects, which may provide a new option for early diagnosis and treatment of AS.

Increased thyroid stimulating hormone (TSH) as a possible risk factor for atherosclerosis in subclinical hypothyroidism

Primary hypothyroidism (PHT) is associated with an increased risk for the development of atherosclerosis (AS) and other cardiovascular disorders. PHT induces atherosclerosis (AS) through the induction of endothelial dysfunction, and insulin resistance (IR). PHT promotes vasoconstriction and the development of hypertension. However, patients with subclinical PHT with normal thyroid hormones (THs) are also at risk for cardiovascular complications. In subclinical PHT, increasing thyroid stimulating hormone (TSH) levels could be one of the causative factors intricate in the progression of cardiovascular complications including AS. Nevertheless, the mechanistic role of PHT in AS has not been fully clarified in relation to increased TSH. Therefore, in this review, we discuss the association between increased TSH and AS, and how increased TSH may be involved in the pathogenesis of AS. In addition, we also discuss how L-thyroxine treatment affects the development of AS.

Macrophage polarisation and inflammatory mechanisms in atherosclerosis: Implications for prevention and treatment

Atherosclerosis is a chronic inflammatory disease characterised by plaque accumulation in the arteries. Macrophages are immune cells that are crucial in the development of atherosclerosis. Macrophages can adopt different phenotypes, with the M1 phenotype promoting inflammation while the M2 phenotype counteracting it. This review focuses on the factors that drive the polarisation of M1 macrophages towards a pro-inflammatory phenotype during AS. Additionally, we explored metabolic reprogramming mechanisms and cytokines secretion by M1 macrophages. Hyperlipidaemia is widely recognised as a major risk factor for atherosclerosis. Modified lipoproteins released in the presence of hyperlipidaemia can trigger the release of cytokines and recruit circulating monocytes, which adhere to the damaged endothelium and differentiate into macrophages. Macrophages engulf lipids, leading to the formation of foam cells. As atherosclerosis progresses, foam cells become the necrotic core within the atherosclerotic plaques, destabilising them and triggering ischaemic disease. Furthermore, we discuss recent research focusing on targeting macrophages or inflammatory pathways for preventive or therapeutic purposes. These include statins, PCSK9 inhibitors, and promising nanotargeted drugs. These new developments hold the potential for the prevention and treatment of atherosclerosis and its related complications.

The anti-inflammatory properties of vinpocetine mediates its therapeutic potential in management of atherosclerosis

Atherosclerosis (AS) formation is enhanced by different mechanisms including cytokine generation, vascular smooth muscle cell proliferation, and migration. One of the recent treatments towards endothelial dysfunction and AS is Vinpocetine (VPN). VPN is a potent inhibitor of phosphodiesterase enzyme 1 (PDE-1) and has anti-inflammatory and antioxidant effects through inhibition the expression of nuclear factor kappa B (NF-κB). VPN has been shown to be effective against the development and progression of AS. However, the underlying molecular mechanism was not fully clarified. Consequently, objective of the present review was to discuss the mechanistic role of VPN in the pathogenesis AS. Most of pro-inflammatory cytokines that released from macrophages are inhibited by action of VPN through NF-κB-dependent mechanism. VPN blocks monocyte adhesion and migration by constraining the expression and action of pro-inflammatory cytokines. As well, VPN is effective in reducing of oxidative stress a cornerstone in the pathogenesis of AS through inhibition of NF-κB and PDE1. VPN promotes plaque stability and prevents the erosion and rupture of atherosclerotic plaque. In conclusion, VPN through mitigation of inflammatory and oxidative stress, and improvement of plaque stability effects could be effective agent in the management of AS.

Morus alba L. (Sangzhi) alkaloids mitigate atherosclerosis by regulating M1/M2 macrophage polarization

BACKGROUND

Atherosclerosis (AS) is an important cause of cardiovascular disease, posing a substantial health risk. Recognized as a chronic inflammatory disorder, AS hinges on the pivotal involvement of macrophages in arterial inflammation, participating in its formation and progression. Sangzhi alkaloid (SZ-A) is a novel natural alkaloid extracted from the mulberry branches, has extensive pharmacological effects and stable pharmacokinetic characteristics. However, the effects and mechanisms of SZ-A on AS remain unclear.

PURPOSE

To explore the effect and underlying mechanisms of SZ-A on inflammation mediated by macrophages and its role in AS development.

METHODS

Atherosclerosis was induced in vivo in apolipoprotein E-deficient mice through a high-fat and high-choline diet. We utilized macrophages and vascular endothelial cells to investigate the effects of SZ-A on macrophage polarization and its anti-inflammatory properties on endothelial cells in vitro. The transcriptomic analyses were used to investigate the major molecule that mediates cell-cell interactions and the antiatherogenic mechanisms of SZ-A based on AS, subsequently validated in vivo and in vitro.

RESULTS

SZ-A demonstrated a significant inhibition in vascular inflammation and alleviation of AS severity by mitigating macrophage infiltration and modulating M1/M2 macrophage polarization in vitro and in vivo. Moreover, SZ-A effectively reduced the release of the proinflammatory mediator C-X-C motif chemokine ligand (CXCL)-10, predominantly secreted by M1 macrophages. This reduction in CXCL-10 contributed to improved endothelial cell function, reduced recruitment of additional macrophages, and inhibited the inflammatory amplification effect. This ultimately led to the suppression of atherogenesis.

CONCLUSION

SZ-A exhibited potent anti-inflammatory effects by inhibiting macrophage-mediated inflammation, providing a new therapeutic avenue against AS. This is the first study demonstrating the efficacy of SZ-A in alleviating AS severity and offers novel insights into its anti-inflammatory mechanism.

Engineering Nanoplatforms for Theranostics of Atherosclerotic Plaques

Atherosclerotic plaque formation is considered the primary pathological mechanism underlying atherosclerotic cardiovascular diseases, leading to severe cardiovascular events such as stroke, acute coronary syndromes, and even sudden cardiac death. Early detection and timely intervention of plaques are challenging due to the lack of typical symptoms in the initial stages. Therefore, precise early detection and intervention play a crucial role in risk stratification of atherosclerotic plaques and achieving favorable post-interventional outcomes. The continuously advancing nanoplatforms have demonstrated numerous advantages including high signal-to-noise ratio, enhanced bioavailability, and specific targeting capabilities for imaging agents and therapeutic drugs, enabling effective visualization and management of atherosclerotic plaques. Motivated by these superior properties, various noninvasive imaging modalities for early recognition of plaques in the preliminary stage of atherosclerosis are comprehensively summarized. Additionally, several therapeutic strategies are proposed to enhance the efficacy of treating atherosclerotic plaques. Finally, existing challenges and promising prospects for accelerating clinical translation of nanoplatform-based molecular imaging and therapy for atherosclerotic plaques are discussed. In conclusion, this review provides an insightful perspective on the diagnosis and therapy of atherosclerotic plaques.

Macrophage Ferroptosis Promotes MMP2/9 Overexpression Induced by Hemin in Hemorrhagic Plaque

BACKGROUND

 Intra-plaque hemorrhage (IPH) leads to rapid plaque progression and instability through upregulation of matrix metalloproteinases (MMPs) and collagen degradation. Hemoglobin-derived hemin during IPH promotes plaque instability. We investigated whether hemin affects MMP overexpression in macrophages and explored the underlying mechanisms.

MATERIAL AND METHODS

 In vivo, hemorrhagic plaque models were established in rabbits and ApoE-/- mice. Ferrostatin-1 was used to inhibit ferroptosis. Plaque size, collagen, and MMP2/9 levels were evaluated using immunohistochemistry, H&E, Sirius Red, and Masson staining. In vitro, mouse peritoneal macrophages were extracted. Western blot and ELISA were used to measure MMP2/9 levels. Bioinformatics analysis investigated the association between MMPs and ferroptosis pathway genes. Macrophage ferroptosis was assessed by evaluating cell viability, lipid reactive oxygen species, mitochondrial ultrastructure, iron content, and COX2 levels after pretreatment with cell death inhibitors. Hemin's impact on ferroptosis and MMP expression was studied using Ferrostatin-1 and SB202190.

RESULTS

 In the rabbit hemorrhagic plaques, hemin deposition and overexpression of MMP2/9 were observed, particularly in macrophage-enriched regions. In vitro, hemin induced ferroptosis and MMP2/9 expression in macrophages. Ferrostatin-1 and SB202190 inhibited hemin-induced MMP2/9 overexpression. Ferrostatin-1 inhibited p38 phosphorylation in macrophages. Ferostatin-1 inhibits macrophage ferroptosis, reduces MMP2/9 levels in plaques, and stabilizes the hemorrhagic plaques.

CONCLUSION

 Our results suggested that hemin-induced macrophage ferroptosis promotes p38 pathway activation and MMP2/9 overexpression, which may play a crucial role in increasing hemorrhagic plaque vulnerability. These findings provide insights into the pathogenesis of hemorrhagic plaques and suggest that targeting macrophage ferroptosis may be a promising strategy for stabilizing vulnerable plaque.

Advances in the treatment of atherosclerosis with ligand-modified nanocarriers

Atherosclerosis, a chronic disease associated with metabolism, poses a significant risk to human well-being. Currently, existing treatments for atherosclerosis lack sufficient efficiency, while the utilization of surface-modified nanoparticles holds the potential to deliver highly effective therapeutic outcomes. These nanoparticles can target and bind to specific receptors that are abnormally over-expressed in atherosclerotic conditions. This paper reviews recent research (2018-present) advances in various ligand-modified nanoparticle systems targeting atherosclerosis by specifically targeting signature molecules in the hope of precise treatment at the molecular level and concludes with a discussion of the challenges and prospects in this field. The intention of this review is to inspire novel concepts for the design and advancement of targeted nanomedicines tailored specifically for the treatment of atherosclerosis.

Macrophages in cardiovascular diseases: molecular mechanisms and therapeutic targets

The immune response holds a pivotal role in cardiovascular disease development. As multifunctional cells of the innate immune system, macrophages play an essential role in initial inflammatory response that occurs following cardiovascular injury, thereby inducing subsequent damage while also facilitating recovery. Meanwhile, the diverse phenotypes and phenotypic alterations of macrophages strongly associate with distinct types and severity of cardiovascular diseases, including coronary heart disease, valvular disease, myocarditis, cardiomyopathy, heart failure, atherosclerosis and aneurysm, which underscores the importance of investigating macrophage regulatory mechanisms within the context of specific diseases. Besides, recent strides in single-cell sequencing technologies have revealed macrophage heterogeneity, cell-cell interactions, and downstream mechanisms of therapeutic targets at a higher resolution, which brings new perspectives into macrophage-mediated mechanisms and potential therapeutic targets in cardiovascular diseases. Remarkably, myocardial fibrosis, a prevalent characteristic in most cardiac diseases, remains a formidable clinical challenge, necessitating a profound investigation into the impact of macrophages on myocardial fibrosis within the context of cardiac diseases. In this review, we systematically summarize the diverse phenotypic and functional plasticity of macrophages in regulatory mechanisms of cardiovascular diseases and unprecedented insights introduced by single-cell sequencing technologies, with a focus on different causes and characteristics of diseases, especially the relationship between inflammation and fibrosis in cardiac diseases (myocardial infarction, pressure overload, myocarditis, dilated cardiomyopathy, diabetic cardiomyopathy and cardiac aging) and the relationship between inflammation and vascular injury in vascular diseases (atherosclerosis and aneurysm). Finally, we also highlight the preclinical/clinical macrophage targeting strategies and translational implications.

Multidirectional Intervention of Chinese Herbal Medicine in the Prevention and Treatment of Atherosclerosis: From Endothelial Protection to Immunomodulation

Atherosclerosis is a significant risk factor for developing cardiovascular disease and a leading cause of death worldwide. The occurrence of atherosclerosis is closely related to factors such as endothelial injury, lipid deposition, immunity, and inflammation. Conventional statins, currently used in atherosclerosis treatment, have numerous adverse side effects that limit their clinical utility, prompting the urgent need to identify safer and more effective therapeutic alternatives. Growing evidence indicates the significant potential of Chinese herbs in atherosclerosis treatment. Herbal monomer components, such as natural flavonoid compounds extracted from herbs like Coptis chinensis and Panax notoginseng, have been utilized for their lipid-lowering and inflammation-inhibiting effects in atherosclerosis treatment. These herbs can be used as single components in treating diseases and with other Chinese medicines to form herbal combinations. This approach targets the disease mechanism in multiple ways, enhancing the therapeutic effects. Thus, this review examines the roles of Chinese herbal medicine monomers and Chinese herbal compounds in inhibiting atherosclerosis, including regulating lipids, improving endothelial function, reducing oxidative stress, regulating inflammation and the immune response, and apoptosis. By highlighting these roles, our study offers new perspectives on atherosclerosis treatment with Chinese herbs and is anticipated to contribute to advancements in related research fields.

The novel vaccines targeting interleukin-1 receptor type I

OBJECTIVE

There is mounting evidence indicating that atherosclerosis represents a persistent inflammatory process, characterized by the presence of inflammation at various stages of the disease. Interleukin-1 (IL-1) precisely triggers inflammatory signaling pathways by binding to interleukin-1 receptor type I (IL-1R1). Inhibition of this signaling pathway contributes to the prevention of atherosclerosis and myocardial infarction. The objective of this research is to develop therapeutic vaccines targeting IL-1R1 as a preventive measure against atherosclerosis and myocardial infarction.

METHODS

ILRQβ-007 and ILRQβ-008 vaccines were screened, prepared and then used to immunize high-fat-diet fed ApoE-/- mice and C57BL/6J mice following myocardial infarction. Progression of atherosclerosis in ApoE-/- mice was assessed primarily by oil-red staining of the entire aorta and aortic root, as well as by detecting the extent of macrophage infiltration. The post-infarction cardiac function in C57BL/6J mice were evaluated using cardiac ultrasound and histological staining.

RESULTS

ILRQβ-007 and ILRQβ-008 vaccines stimulated animals to produce high titers of antibodies that effectively inhibited the binding of interleukin-1β and interleukin-1α to IL-1R1. Both vaccines effectively reduced atherosclerotic plaque area, promoted plaque stabilization, decreased macrophage infiltration in plaques and influenced macrophage polarization, as well as decreasing levels of inflammatory factors in the aorta, serum, and ependymal fat in ApoE-/- mice. Furthermore, these vaccines dramatically improved cardiac function and macrophage infiltration in C57BL/6J mice following myocardial infarction. Notably, no significant immune-mediated damage was observed in immunized animals.

CONCLUSION

The vaccines targeting the IL-1R1 would be a novel and promising treatment for the atherosclerosis and myocardial infarction.

Emerging regulatory mechanisms in cardiovascular disease: Ferroptosis

Ferroptosis, distinct from apoptosis, necrosis, autophagy, and other types of cell death, is a novel iron-dependent regulated cell death characterized by the accumulation of lipid peroxides and redox imbalance with distinct morphological, biochemical, and genetic features. Dysregulation of iron homeostasis, the disruption of antioxidative stress pathways and lipid peroxidation are crucial in ferroptosis. Ferroptosis is involved in the pathogenesis of several cardiovascular diseases, including atherosclerosis, cardiomyopathy, myocardial infarction, ischemia-reperfusion injury, abdominal aortic aneurysm, aortic dissection, and heart failure. Therefore, a comprehensive understanding of the mechanisms that regulate ferroptosis in cardiovascular diseases will enhance the prevention and treatment of these diseases. This review discusses the latest findings on the molecular mechanisms of ferroptosis and its regulation in cardiovascular diseases, the application of ferroptosis modulators in cardiovascular diseases, and the role of traditional Chinese medicines in ferroptosis regulation to provide a comprehensive understanding of the pathogenesis of cardiovascular diseases and identify new prevention and treatment options.

Unveiling Atherosclerotic Plaque Heterogeneity and SPP1+/VCAN+ Macrophage Subtype Prognostic Significance Through Integrative Single-Cell and Bulk-Seq Analysis

Background

Dysregulated macrophages are important causes of Atherosclerosis (AS) formation and increased plaque instability, but the heterogeneity of these plaques and the role of macrophage subtypes in plaque instability have yet to be clarified.

Methods

This study integrates single-cell and bulk-seq data to analyze atherosclerotic plaques. Unsupervised clustering was used to reveal distinct plaque subtypes, while survival analysis and gene set variation analysis (GSVA) methods helped in understanding their clinical outcomes. Enrichment of differential expression of macrophage genes (DEMGs) score and pseudo-trajectory analysis were utilized to explore the biological functions and differentiation stages of macrophage subtypes in AS progression. Additionally, CellChat and the BayesPrism deconvolution method were used to elucidate macrophage subtype interaction and their prognostic significance at single-cell resolution. Finally, the expression of biomarkers was validated in mouse experiments.

Results

Three distinct AS plaque subtypes were identified, with cluster 3 plaque subtype being particularly associated with higher immune infiltration and poorer prognosis. The DEMGs score exhibited a significant elevation in three macrophage subtypes (SPP1+/VCAN+ macrophages, IL1B+ macrophages, and FLT3LG+ macrophages), associated with cluster 3 plaque subtype and highlighted the prognostic significance of these subtypes. Activation trajectory of the macrophage subtypes is divided into three states (Pre-branch, Cell fate 1, and Cell fate 2), and Cell fate 2 (SPP1+/VCAN+ macrophages, IL1B+ macrophages, and FLT3LG+ macrophages dominant) exhibiting the highest DEMGs score, distinct interactions with other cell components, and relating to poorer prognosis of ischemic events. This study also uncovered a unique SPP1+/VCAN+ macrophage subtype, rare in quantity but significant in influencing AS progression. Machine learning algorithms identified 10 biomarkers crucial for AS diagnosis. The validation of these biomarkers was performed using Mendelian Randomization analysis and in vitro methods, supporting their relevance in AS pathology.

Conclusion

Our study provides a comprehensive view of AS plaque heterogeneity and the prognostic significance of macrophage subtypes in plaque instability.

Molecular Pathways of Vulnerable Carotid Plaques at Risk of Ischemic Stroke: A Narrative Review

The concept of vulnerable carotid plaques is pivotal in understanding the pathophysiology of ischemic stroke secondary to large-artery atherosclerosis. In macroscopic evaluation, vulnerable plaques are characterized by one or more of the following features: microcalcification; neovascularization; lipid-rich necrotic cores (LRNCs); intraplaque hemorrhage (IPH); thin fibrous caps; plaque surface ulceration; huge dimensions, suggesting stenosis; and plaque rupture. Recognizing these macroscopic characteristics is crucial for estimating the risk of cerebrovascular events, also in the case of non-significant (less than 50%) stenosis. Inflammatory biomarkers, such as cytokines and adhesion molecules, lipid-related markers like oxidized low-density lipoprotein (LDL), and proteolytic enzymes capable of degrading extracellular matrix components are among the key molecules that are scrutinized for their associative roles in plaque instability. Through their quantification and evaluation, these biomarkers reveal intricate molecular cross-talk governing plaque inflammation, rupture potential, and thrombogenicity. The current evidence demonstrates that plaque vulnerability phenotypes are multiple and heterogeneous and are associated with many highly complex molecular pathways that determine the activation of an immune-mediated cascade that culminates in thromboinflammation. This narrative review provides a comprehensive analysis of the current knowledge on molecular biomarkers expressed by symptomatic carotid plaques. It explores the association of these biomarkers with the structural and compositional attributes that characterize vulnerable plaques.