Plaque Lipid Research Articles

The Lian-Dou-Qing-Mai Formula activates the PPARγ-LXRα-ABCA1/ABCG1 pathway by regulating IL-10, leading to the promotion of cholesterol efflux and a reduction in atherosclerotic plaques.

To observe the effect of the Lian-Dou-Qing-Mai (LDQM) formula on lipid metabolism in mice and explore its mechanism from the perspective of regulating the PPARγ/LXRα/ABCA1 signaling pathway. THP-1 cells were induced to transform into foam cells with ox-LDL. Atherosclerosis (AS) models were constructed using a high-fat diet in ApoE-/- mice. Detection kits were used to evaluate triglyceride (TG) and total cholesterol (TC) content; TNF-α, MCP-1, MMP-9, TMP-1, PPARγ, LXRα, ABCA1, and ABCG1 mRNA and protein expression were identified using real-time PCR and western blot. Interleukin-10 (IL-10) blood levels were measured using an enzyme-linked immunosorbent assay (ELISA), and aortic plaque development and lipid deposition were seen using hematoxylin and eosin (HE) and oil red O staining, respectively. In the cell model, LDQM could inhibit the formation of THP-1 macrophage-derived foam cells and the expression of inflammatory factors, promote macrophage cholesterol efflux, increase the expression of IL-10, and activate the PPARγ-LXRα-ABCA1/ABCG1 pathway. Additional IL-10 treatment further promotes LDQM-induced cholesterol efflux in THP-1 cells; in In vivo models, LDQM inhibited the area of atherosclerotic lesions, aortic lipid deposition, and inflammation levels in ApoE-/- mice through IL-10, and activated the expression level of the PPARγ-LXRα-ABCA1/ABCG1 pathway. LDQM may affect the PPARγ/LXRα/ABCA1 signaling pathway through IL-10, regulate lipid metabolism, reduce serum inflammatory expression and lipid deposition, and improve the formation of atheroplaques.

Reactive Oxygen Species-Responsive Nanoparticle Delivery of Small Interfering Ribonucleic Acid Targeting Olfactory Receptor 2 for Atherosclerosis Theranostics.

Atherosclerosis (AS) is a chronic inflammatory disorder characterized by arterial intimal lipid plaques. Small interfering ribonucleic acid (siRNA)-based therapies, with their ability to suppress specific genes with high targeting precision and minimal side effects, have shown great potential for AS treatment. However, targets of siRNA therapies based on macrophages for AS treatment are still limited. Olfactory receptor 2 (Olfr2), a potential target for plaque formation, was discovered recently. Herein, anti-Olfr2 siRNA (si-Olfr2) targeting macrophages was designed, and the theranostic platform encapsulating si-Olfr2 to target macrophages within atherosclerotic lesions was also developed, with the aim of downregulating Olfr2, as well as diagnosing AS through photoacoustic imaging (PAI) in the second near-infrared (NIR-II) window with high resolution. By utilization of a reactive oxygen species (ROS)-responsive nanocarrier system, the expression of Olfr2 on macrophages within atherosclerotic plaques was effectively downregulated, leading to the inhibition of NLR family pyrin domain containing 3 (NLRP3) inflammasome activation and interleukin-1 β (IL-1β) secretion, thereby reducing the formation of atherosclerotic plaques. As manifested by decreased Olfr2 expression, the lesions exhibited a significantly alleviated inflammatory response that led to reduced lipid deposition, macrophage apoptosis, and a noticeable decrease in the necrotic areas. This study provides a proof of concept for evaluating the theranostic nanoplatform to specifically deliver si-Olfr2 to lesional macrophages for AS diagnosis and treatment.

CCTA-Derived Fat Attenuation Index Predict Future Percutaneous Coronary Intervention.

This study aims to investigate the differences in plaque characteristics and fat attenuation index (FAI) between in patients who received revascularization versus those who did not receive revascularization and examine whether the machine-learning (ML) based model constructed by plaque characteristics and FAI can predict revascularization. This study was a post hoc analysis of a prospective single-center registry of sequential patients undergoing CCTA, referred from inpatient and emergency department settings (n = 261, 63 years ± 8; 188 men). The primary outcome was revascularization by percutaneous coronary revascularization. The CTA images were analyzed by experienced radiologists using a dedicated workstation in a blinded fashion. The ML-based model was automatically computed. The study cohort consisted of 261 subjects. Revascularization was performed in 105 subjects. Patients receiving revascularization had higher FAI value (67.35±5.49 Hu vs -80.10±7.75 Hu, p < 0.001) as well as higher plaque length, calcified, lipid and fibrous plaque burden and volume. When FAI was incorporated into a ML risk model based on plaque characteristics to predict revascularization, the area under the curve increased from 0.84 (95% CI: 0.68-0.99) to 0.95 (95% CI: 0.88-1.00). ML-algorithms based on FAI and characteristics could help improve the prediction of future revascularization and identify patients likely to receive revascularization. Pre-procedural FAI could help guide revascularization in symptomatic CAD patients.

Pharmacological inhibition of histone deacetylase alleviates chronic unpredictable stress induced atherosclerosis and endothelial dysfunction via upregulation of BDNF

Long-term stress is a significant risk factor for cardiovascular diseases, including atherosclerosis and endothelial dysfunction. Moreover, prolonged stress has shown to negatively regulate central BDNF expression. The role of central BDNF in CNS disorders is well studied until recently the peripheral BDNF was also found to be involved in endothelial function regulation and atherosclerosis. The peripheral BDNF and its role in chronic stress-induced atherosclerosis and endothelial dysfunction remain unclear. Therefore, we aimed to elucidate the role of BDNF and its modulation by the HDAC inhibitor valproic acid (VA) in chronic unpredictable stress (CUS)-induced atherosclerosis and endothelial dysfunction. We demonstrated that a 10-week CUS mouse model substantially decreases central and peripheral BDNF expression, resulting in enhanced serum lipid indices, plaque deposition, fibrosis, and CD68 expression in thoracic aortas. Further, parameters associated with endothelial dysfunction such as increased levels of endothelin-1 (ET-1), adhesion molecules like VCAM-1, M1 macrophage markers, and decreased M2 macrophage markers, eNOS expression, and nitrite levels in aortas, were also observed. VA (50 mg/kg, 14 days, i. p.) was administered to mice following 8 weeks of CUS exposure until the end of the experimental procedure. VA significantly prevented the decrease in BDNF, eNOS and nitrite levels, reduced lesion formation and fibrosis in thoracic aortas and increased ET-1, and VCAM-1 followed by M2 polarization in VA-treated mice. The study highlights the potential of epigenetic modulation of BDNF as a therapeutic target, in stress-induced cardiovascular pathologies and suggests that VA could be a promising agent for mitigating CUS-induced endothelial dysfunction and atherosclerosis by BDNF modulation.

Safety and efficacy of PCSK9 inhibitor (evolocumab) in patients with non-ST segment elevation acute coronary syndrome and non-culprit artery critical lesions: a randomised controlled trial protocol (SPECIAL study)

IntroductionPatients with non-ST segment elevation acute coronary syndrome (NSTE-ACS) and concomitant multivessel coronary artery disease (CAD) are considered patients with extremely high-risk atherosclerotic cardiovascular disease (ASCVD), and current guidelines specify...

Guizhitongluo Tablet inhibits atherosclerosis and foam cell formation through regulating Piezo1/NLRP3 mediated macrophage pyroptosis

BackgroundAtherosclerosis (AS) is the main pathological basis for the development of cardiovascular diseases. Vascular inflammation is an important factor in the formation of AS, and macrophage pyroptosis plays a key role in AS due to its unique inflammatory response. Guizhitongluo Tablet (GZTLT) has shown clinically effective in treating patients with AS, but its mechanism is elusive. PurposeThis study was to determine the effects of GZTLT on atherosclerotic vascular inflammation and pyroptosis and to understand its underlying mechanism. Materials and methodsThe active constituents of GZTLT were analysed by means of UPLC-HRMS. In vivo experiments were performed using ApoE−/− mice fed a high fat diet for 8 weeks, followed by treatment with varying concentrations of GZTLT orally by gavage and GsMTx4 (GS) intraperitoneally and followed for another 8 weeks. Oil red O, Haematoxylin-eosin (HE) and Masson staining were employed to examine the lipid content, plaque size, and collagen fibre content of the mouse aorta. Immunofluorescence staining was utilised to identify macrophage infiltration, as well as the expression of Piezo1 and NLRP3 proteins in aortic plaques. The levels of aortic inflammatory factors were determined using RT-PCR and ELISA. In vitro, foam cell formation in bone marrow-derived macrophages (BMDMs) was observed using Oil Red O staining. Intracellular Ca2+ measurements were performed to detect the calcium influx in BMDMs, and the expression of NLRP3 and its related proteins were detected by Western blot. ResultsThe UPLC-HRMS analysis revealed 31 major components of GZTLT. Our data showed that GZTLT inhibited aortic plaque formation in mice and increased plaque collagen fibre content to stabilise plaques. In addition, GZTLT could restrain the expression of serum lipid levels and suppress macrophage foam cell formation. Further studies found that GZTLT inhibited macrophage infiltration in aortic plaques and suppressed the expression of inflammatory factors. It is noteworthy that GZTLT can restrain Piezo1 expression and reduce Ca2+ influx in BMDMs. Additionally, we found that GZTLT could regulate NLRP3 activation and pyroptosis by inhibiting Piezo1. ConclusionThe present study suggests that GZTLT inhibits vascular inflammation and macrophage pyroptosis through the Piezo1/NLRP3 signaling pathway, thereby delaying AS development. Our finding provides a potential target for AS treatment and drug discovery.

Integrative Single-Plaque Analysis Reveals Signature Aβ and Lipid Profiles in the Alzheimer's Brain.

Cerebral accumulation of amyloid-β (Aβ) initiates molecular and cellular cascades that lead to Alzheimer's disease (AD). However, amyloid deposition does not invariably lead to dementia. Amyloid-positive but cognitively unaffected (AP-CU) individuals present widespread amyloid pathology, suggesting that molecular signatures more complex than the total amyloid burden are required to better differentiate AD from AP-CU cases. Motivated by the essential role of Aβ and the key lipid involvement in AD pathogenesis, we applied multimodal mass spectrometry imaging (MSI) and machine learning (ML) to investigate amyloid plaque heterogeneity, regarding Aβ and lipid composition, in AP-CU versus AD brain samples at the single-plaque level. Instead of focusing on a population mean, our analytical approach allowed the investigation of large populations of plaques at the single-plaque level. We found that different (sub)populations of amyloid plaques, differing in Aβ and lipid composition, coexist in the brain samples studied. The integration of MSI data with ML-based feature extraction further revealed that plaque-associated gangliosides GM2 and GM1, as well as Aβ1-38, but not Aβ1-42, are relevant differentiators between the investigated pathologies. The pinpointed differences may guide further fundamental research investigating the role of amyloid plaque heterogeneity in AD pathogenesis/progression and may provide molecular clues for further development of emerging immunotherapies to effectively target toxic amyloid assemblies in AD therapy. Our study exemplifies how an integrative analytical strategy facilitates the unraveling of complex biochemical phenomena, advancing our understanding of AD from an analytical perspective and offering potential avenues for the refinement of diagnostic tools.

Increasing the rate of datasets amenable to CTFFR and quantitative plaque analysis: Value of software for reducing stair-step artifacts demonstrated in photon-counting detector CT

PurposeTo determine the value of an algorithm for reducing stair-step artifacts for advanced coronary analyses in sequential mode coronary CT angiography (CCTA). MethodsForty patients undergoing sequential mode photon-counting detector CCTA with at least one stair-step artifact were included. Twenty patients (14 males; mean age 57±17years) with 45 segments showing stair-step artifacts and without atherosclerosis were included for CTFFR analysis. Twenty patients (20 males; mean age 74±13years) with 22 segments showing stair-step artifacts crossing an atherosclerotic plaque were included for quantitative plaque analysis. Artifacts were graded, and CTFFR and quantitative coronary plaque analyses were performed in standard reconstructions and in those reconstructed with a software (entitled ZeeFree) for artifact reduction. ResultsStair-step artifacts were significantly reduced in ZeeFree compared to standard reconstructions (p<0.05). In standard reconstructions, CTFFR was not feasible in 3/45 (7 %) segments but was feasible in all ZeeFree reconstructions. In 9/45 (20 %) segments without atherosclerosis, the ZeeFree algorithm led to a change of CTFFR values from pathologic in standard to physiologic values in ZeeFree reconstructions. In one segment (1/22, 5 %), quantitative plaque analysis was not feasible in standard but only in ZeeFree reconstruction. The mean overall plaque volume (111±60 mm3), the calcific (77±47 mm3), fibrotic (31±28 mm3), and lipidic (4±3 mm3) plaque components were higher in standard than in ZeeFree reconstructions (overall 75±50 mm3, p<0.001; calcific 51±42 mm3, p<0.001; fibrotic 22±19 mm3, p<0.05; lipidic 3±3 mm3, p=0.055). ConclusionDespite the lack of reference standard modalities for CTFFR and coronary plaque analysis, initial evidence indicates that an algorithm for reducing stair-step artifacts in sequential mode CCTA increases the rate and quality of datasets amenable to advanced coronary artery analysis, hereby potentially improving patient management.

Dual-Targeting EGCG/NO-Supplying protein assembled nanoparticles with Multi-Synergistic effects against atherosclerosis

Limited therapeutic options are available to effectively preventing atherosclerosis. Inflammatory endothelial cells, foamy macrophages, and high protease levels contribute to atherosclerotic plaque formation. Studies have shown that catechins effectively scavenge reactive oxygen species (ROS), inhibit monocyte adhesion and reduce cholesterol levels, while nitric oxide (NO) enhances endothelial function. However, due to the poor stability and bioavailability of catechins and the toxicity from the burst release of current synthetic small molecules NO donor, effective deliveryof these bioactive compounds to treat atherosclerosis is still a challenge. Herein, a catechin/protein-based NO donor co-delivery nanosystem was designed for combinatorial anti-atherosclerotic therapy. We engineered a (−)-epigallocatechin-3-gallate (EGCG)/NO-releasing protein co-assembled nanocomplex based on specific catechin-protein interactions. Furthermore, the nanocomplex was surface modified with fucoidan (Fu), a sulfated polysaccharide with anti-inflammatory activity. This nanocomplex exhibits sensitivity to ROS, pH, and enzymes. The Fu-functionalized nanoparticles specifically accumulates in atherosclerotic plaques mediated by P-selectin on inflamed endothelial cells and scavenger receptor A (SR-A) on foamy macrophages. Under environmental stimuli that simulate the condition of plaque, the nanoparticles are readily activated to release EGCG and NO in response to excess ROS and high protease levels, exerting the multi-synergistic anti-atherosclerosic effects on reducing monocyte adhesion, promoting NO production to proliferate endothelial cells, lowering ROS levels, and decreasing the foam cell formation in vitro, and reducing lipid accumulation, plaque size, and inflammatory cytokines release in high-fat diet-induced atherosclerosis model in ApoE−/− mice. The integration of plaques targeting ability and multiple therapeutic functions can provide an advanced therapeutic strategy foratherosclerosistreatment.

LARP7 overexpression alleviates aortic senescence and atherosclerosis.

Atherosclerosis, characterized by the accumulation of lipid plaques on the inner walls of arteries, is the leading cause of heart attack, stroke and severe ischemic injuries. Senescent cells have been found to accumulate within atherosclerotic lesions and contribute to the progression of atherosclerosis. In our previous study, we discovered that suppressing Larp7 accelerates senescence by inhibiting Sirt1 activity, resulting in increased atherosclerosis in high-fat diet (HFD) fed and ApoE deficient (ApoEKO) mice. However, there has been no direct evidence demonstrating Larp7 per se could attenuate atherosclerosis. To this end, we generated a tetO-controlled and Cre-activated Larp7 gain-of-function mouse. Through RT-PCR and western blotting, we confirmed Larp7 overexpression in the aortas of HFD-fed ApoEKO; Larp7tetO mice. Larp7 overexpression led to increased Sirt1 activity and decreased cellular senescence signals mediated by p53/p65 in the aortas. Additionally, Larp7 overexpression reduced the presence of p16-positive senescent cells in the aortic lesions. Furthermore, Larp7 overexpression resulted in a decrease in pro-inflammatory macrophages and SASP factors. Consequently, Larp7 overexpression led to a reduction in the area of atherosclerotic lesions in HFD-fed ApoEKO; Larp7tetO mice. In summary, our study provides evidence that Larp7 overexpression holds promise as an approach to inhibit cellular senescence and prevent atherosclerosis.

Low to moderate dose 137Cs (γ) radiation promotes M2 type macrophage skewing and reduces atherosclerotic plaque CD68+ cell content in ApoE(−/−) mice

The effects of low doses of ionizing radiation on atherosclerosis remain uncertain, particularly as regards the generation of pro- or anti-inflammatory responses, and the time scale at which such effects can occur following irradiation. To explore these phenomena, we exposed atheroprone ApoE(−/−) mice to a single dose of 0, 0.05, 0.5 or 1 Gy of 137Cs (γ) administered at a 10.35 mGy min−1 dose rate and evaluated short-term (1–10 days) and long-term consequences (100 days). Bone marrow-derived macrophages were derived from mice 1 day after exposure. Irradiation was associated with a significant skewing of M0 and M2 polarized macrophages towards the M2 phenotype, as demonstrated by an increased mRNA expression of Retnla, Arg1, and Chil3 in cells from mice exposed to 0.5 or 1 Gy compared with non-irradiated animals. Minimal effects were noted in M1 cells or M1 marker mRNA. Concurrently, we observed a reduced secretion of IL-1β but enhanced IL-10 release from M0 and M2 macrophages. Effects of irradiation on circulating monocytes were most marked at day 10 post-exposure, when the 1 Gy dose was associated with enhanced numbers of both Ly6CHigh and Ly6Low cells. By day 100, levels of circulating monocytes in irradiated and non-irradiated mice were equivalent, but anti-inflammatory Ly6CLow monocytes were significantly increased in the spleen of mice exposed to 0.05 or 1 Gy. Long term exposures did not affect atherosclerotic plaque size or lipid content, as determined by Oil red O staining, whatever the dose applied. Similarly, irradiation did not affect atherosclerotic plaque collagen or smooth muscle cell content. However, we found that lesion CD68+ cell content tended to decrease with rising doses of radioactivity exposure, culminating in a significant reduction of plaque macrophage content at 1 Gy. Taken together, our results show that short- and long-term exposures to low to moderate doses of ionizing radiation drive an anti-inflammatory response, skewing bone marrow-derived macrophages towards an IL-10-secreting M2 phenotype and decreasing plaque macrophage content. These results suggest a low-grade athero-protective effect of low and moderate doses of ionizing radiation.

Mitochondria targeted esculetin administration improves insulin resistance and hyperglycemia-induced atherosclerosis in db/db mice.

The development and progression of hyperglycemia (HG) and HG-associated atherosclerosis are exacerbated by mitochondrial dysfunction due to dysregulated mitochondria-derived ROS generation. We recently synthesized a novel mitochondria-targeted esculetin (Mito-Esc) and tested its dose-response therapeutic efficacy in mitigating HG-induced atherosclerosis in db/db mice. In comparison to simvastatin and pioglitazone, Mito-Esc administration resulted in a considerable reduction in body weights and improved glucose homeostasis, possibly by reducing hepatic gluconeogenesis, as indicated by a reduction in glycogen content, non-esterified free fatty acids (NEFA) levels, and fructose 1,6-bisphosphatase (FBPase) activity. Interestingly, Mito-Esc treatment, by regulating phospho-IRS and phospho-AKT levels, greatly improved palmitate-induced insulin resistance, resulting in enhanced glucose uptake in adipocytes and HepG2 cells. Also, and importantly, Mito-Esc administration prevented HG-induced atheromatous plaque formation and lipid accumulation in the descending aorta. In addition, Mito-Esc administration inhibited the HG-mediated increase in VACM, ICAM, and MAC3 levels in the aortic tissue, as well as reduced the serum pro-inflammatory cytokines and markers of senescence. In line with this, Mito-Esc significantly inhibited monocyte adherence to human aortic endothelial cells (HAECs) treated with high glucose and reduced high glucose-induced premature senescence in HAECs by activating the AMPK-SIRT1 pathway. In contrast, Mito-Esc failed to regulate high glucose-induced endothelial cell senescence under AMPK/SIRT1-depleted conditions. Together, the therapeutic efficacy of Mito-Esc in the mitigation of hyperglycemia-induced insulin resistance and the associated atherosclerosis is in part mediated by potentiating the AMPK-SIRT1 axis. KEY MESSAGES: Mito-Esc administration significantly mitigates diabetes-induced atherosclerosis. Mito-Esc improves hyperglycemia (HG)-associated insulin resistance. Mito-Esc inhibits HG-induced vascular senescence and inflammation in the aorta. Mito-Esc-mediated activation of the AMPK-SIRT1 axis regulates HG-induced endothelial cell senescence.

Exploring the Mechanism of Fufang Danshen Tablet against Atherosclerosis by Network Pharmacology and Experimental Validation.

Atherosclerosis is the main pathological basis of cardiovascular diseases (CVDs). Fufang Danshen Tablet (FDT) is a traditional Chinese medicine that has been clinically used to treat CVDs for more than 40 years. Nevertheless, owing to the complexity of the ingredients, the pharmacological mechanism of FDT in the treatment of CVDs has not been fully elucidated. In this study, an integrated strategy of UFLC-Q-TOF-MS/MS, network pharmacology, molecular biology, and transcriptomics was used to elucidate the mechanisms of action of FDT in the treatment of atherosclerosis. In total, 22 absorbed constituents were identified in rat serum after oral administration of FDT. In silico, network pharmacology studies have shown that FDT regulates four key biological functional modules for the treatment of atherosclerosis: oxidative stress, cell apoptosis, energy metabolism, and immune/inflammation. In animal experiments, FDT exerted protective effects against atherosclerosis by reducing the plaque area and lipid levels in ApoE-/- mice. Furthermore, we found that FDT inhibited inflammatory macrophage accumulation by regulating the expression of Selp and Ccl2, which are both involved in monocyte adhesion and migration. The inhibition of monocyte recruitment by FDT is a new perspective to elucidate the anti-atherosclerotic mechanism of FDT, which has not been adopted in previous studies on FDT. Our results may help to elucidate the therapeutic mechanism of FDT against CVDs and provide potential therapeutic targets.

Renal Dysfunction Increases Risk of Adverse Cardiovascular Events in 5-Year Follow-Up Study of Intermediate Coronary Artery Lesions.

BACKGROUND Progression of chronic coronary syndrome (CCS) is influenced by chronic kidney disease (CKD). This 5-year follow-up study aimed to assess 100 patients with 118 intermediate coronary artery lesions evaluated by fractional flow reserve (FFR) and intravascular imaging stratified according to renal function. MATERIAL AND METHODS This prospective study enrolled patients with intermediate coronary stenosis identified by coronary angiogram. Patients with severe renal dysfunction (estimated glomerular filtration rate (eGFR) <45 ml/min/1.73 m²) were excluded from the study. The remaining were divided into 2 groups according to eGFR: 45-60 ml/min/1.73 m² for mild-to-moderate renal dysfunction and >60 ml/min/1.73 m² for no renal dysfunction. We analyzed intermediate-grade stenoses (40-80% as assessed in coronary angiography) with the use of optical coherence tomography (OCT), FFR, and intravascular ultrasound (IVUS). RESULTS Renal dysfunction patients were older (67.7±8.1 vs 63.6±9.7 years, P=0.044). Lesion characteristics, including plaque type and minimal lumen area in OCT, showed no significant differences between the renal dysfunction and no renal dysfunction groups. Thin-cap fibroatheroma, calcific plaques, lipidic plaques, and fibrous plaques had similar prevalence. FFR values and IVUS parameters did not significantly differ between the groups. Over a 5-year follow-up, individuals with mild-to-moderate renal dysfunction had an elevated risk of all-cause mortality and major adverse cardiovascular events in multivariate analyses adjusted for age and sex. CONCLUSIONS Mild-to-moderate renal dysfunction was not associated with significant differences in OCT- and IVUS-derived plaque morphology nor with functional indices characterizing intermediate-grade coronary stenoses. Renal dysfunction was related to a higher risk of all-cause mortality and major adverse cardiovascular events prevalence in 5-year follow-up.

Mild phototherapy mediated by IR780-Gd-OPN nanomicelles suppresses atherosclerotic plaque progression through the activation of the HSP27-regulated NF-κB pathway

Reducing plaque lipid content and enhancing plaque stability without causing extensive apoptosis of foam cells are ideal requirements for developing a safe and effective treatment of atherosclerosis. In this study, we synthesized IR780-Gd-OPN nanomicelles by conjugating osteopontin (OPN) and loading a gadolinium-macrocyclic ligand (Gd-DOTA) onto near-infrared dye IR780-polyethylene glycol polymer. The nanomicelles were employed for mild phototherapy of atherosclerotic plaques and dual-mode imaging with near-infrared fluorescence and magnetic resonance. In vitro results reveal that the mild phototherapy mediated by IR780-Gd-OPN nanomicelles not only activates heat shock protein (HSP) 27 to protect foam cells against apoptosis but also inhibits the nuclear factor kappa-B (NF-κB) pathway to regulate lipid metabolism and macrophage polarization, thereby diminishing the inflammatory response. In vivo results further validate that mild phototherapy effectively reduces plaque lipid content and size while simultaneously enhancing plaque stability by regulating the ratio of M1 and M2-type macrophages. In summary, this study presents a promising approach for developing a safe and highly efficient method for the precise therapeutic visualization of atherosclerosis. Statement of significanceThe rupture of unstable atherosclerotic plaques is a major cause of high mortality rates in cardiovascular diseases. Therefore, the ideal outcome of atherosclerosis treatment is to reduce plaque size while enhancing plaque stability. To address this challenge, we designed IR780-Gd-OPN nanomicelles for mild phototherapy of atherosclerosis. This treatment can effectively reduce plaque size while significantly improving plaque stability by increasing collagen fiber content and elevating the ratio of M2/M1 macrophages, which is mainly attributed to the inhibition of the NF-κB signaling pathway by mild phototherapy-activated HSP27. In summary, our proposed mild phototherapy strategy provides a promising approach for safe and effective treatment of atherosclerosis.

Abstract 1117: Il-1 Signaling On Vascular Smooth Muscle Cells Accelerates Atherosclerosis After Murine Kawasaki Disease Vasculitis

Objective: We have previously shown that Lactobacillus casei cell wall extract (LCWE)-induced Kawasaki disease (KD) vasculitis significantly accelerates atherosclerosis in hypercholesterolemic mice on high fat diet. IL-1 signaling is known to play a key role in both KD vasculitis and in the development of atherosclerosis. Here, we investigated the contribution of IL-1 signaling on vascular smooth muscle cells (VSMCs) in KD vasculitis-induced acceleration of atherosclerosis. Methods: Tamoxifen-inducible VSMC-specific IL-1 receptor ( Il1r1) knockout ( Myh11 Cre -ERT2 Il1r1 Δ/Δ ) mice and Il1r1 fl/fl littermate controls, all on ApoE -/- background, were injected with either PBS or LCWE. Following induction of KD vasculitis for 2 weeks, mice were fed a tamoxifen diet for 2 weeks to induce Il1r1 deletion on VSMCs, before being exposed to 8 weeks of Western diet to promote atherosclerosis. Results: KD vasculitis was associated with a significant acceleration of atherosclerosis, as expected. Myh11 Cre -ERT2 Il1r1 Δ/Δ mice had significantly diminished atherosclerotic plaque size, lipid composition, macrophage infiltration and necrotic core formation in aortic root as well as diminished lipid accumulation in aorta en face measurements compared with Il1r1 fl/fl control mice despite similar cholesterol levels. We also observed that Myh11 Cre -ERT2 Il1r1 Δ/Δ mice had significantly diminished endothelial adhesion molecules VCAM-1 and ICAM-1 expression in the lesion area and serum monocyte chemotaxis protein-1 (MCP-1) level compared with Il1r1 fl/fl control mice, consistent with the reduction of macrophage infiltration that we observed. Conclusions: Our results suggest an important pathophysiologic link between IL-1 signaling, specifically on VSMCs, and subsequent acceleration of atherosclerosis in hypercholesterolemic mice following KD vasculitis. Thus, further studies are warranted on the role of IL-1 signaling not only in acute KD, but also in the subsequent vascular remodeling and complications following acute KD vasculitis including atherosclerosis.

Predictors of late lumen enlargement after drug-coated balloon angioplasty for de novo coronary lesions.

Late lumen enlargement (LLE) - a positive remodelling phenomenon - after drug-coated balloon (DCB) angioplasty for stable coronary disease contributes to a lower restenosis rate. However, lesion characteristics promoting LLE remain unclear. This study aimed to investigate predictive lesion characteristics for LLE using serial optical frequency domain imaging (OFDI) following DCB angioplasty for de novo coronary artery lesions. This retrospective, single-centre observational study included patients with angina pectoris who underwent paclitaxel-coated balloon angioplasty without stenting under OFDI guidance as well as follow-up OFDI. OFDI endpoints were lumen volume, plaque phenotype, and procedure-associated dissection. LLE was defined as a ≥10% increase in the lumen volume of the treated lesion at follow-up. Between August 2016 and December 2019, among patients with successful DCB angioplasty, 108 lesions (83 patients) had available follow-up imaging after a median of 6.1 months. LLE was detected in 44 (40.7%) lesions. Fibrous/fibrocalcific and layered plaques had significantly larger lumen volumes at follow-up than immediately after the index procedure, whereas lipid plaques exhibited no significant difference. Medial dissection with an arc >90° revealed an increased lumen volume. Multivariate analysis showed that layered plaques (odds ratio [OR] 8.73, 95% confidence interval [CI]: 1.92-39.7; p=0.005) and medial dissection with an arc >90° (OR 4.65, 95% CI: 1.63-13.3; p=0.004) were independent LLE predictors. Layered plaques and extensive medial dissection after DCB angioplasty were associated with higher LLE occurrence in de novo coronary lesions. These findings may be clinically applicable to DCB therapeutic strategies based on plaque features.

Abstract 124: IRG1-Itaconate Axis Protects From Cholesterol-Induced Inflammation And Atherosclerosis

Atherosclerosis, the major underlying cause of cardiovascular disease (CVD) mortality, is fueled by a failure to resolve lipid-driven inflammation within the vessel wall. Understanding the immunometabolic mechanisms underpinning sustained inflammation within this microenvironment is needed for the development of novel targeted therapies. Immune responsive gene 1 (IRG) is an enzyme that diverts the TCA cycle intermediate, cis-aconitate, to produce itaconate, a metabolite with anti-microbial and anti-inflammatory functions. We used a translational approach to investigate the therapeutic potential of the Irg1-itaconate axis for human atherosclerosis. Using single cell RNA-sequencing, we found that IRG1 is upregulated in human coronary atherosclerotic lesions compared to patient-matched healthy vasculature, and is primarily expressed by plaque monocytes and macrophages. In mouse models of atherosclerosis, Irg1 was expressed by plaque monocytes, macrophage and neutrophils, but declined with disease progression. Global or hematopoietic Irg1 -deficiency increased atherosclerosis burden, plaque lipid content, and expression of interleukin (IL)-1b. Mechanistically, absence of Irg1 potentiates lipid accumulation and lipid-mediated inflammation via a feed-forward cycle involving increased neutrophil extracellular trap (NET) formation, NET-induced NLRP3 inflammasome priming in macrophages, and subsequent IL-1b release. Conversely, supplementation of the Irg1 pathway using the derivative 4-octyl itaconate (4-OI) reduced atherosclerotic inflammation and promoted beneficial plaque remodeling in mice. To assess the therapeutic potential of 4-OI in humans, we leveraged a validated systems-immunology approach to investigate CVD-related inflammation ex vivo . Using high dimensional single cell analyses, we showed that 4-OI supplementation attenuated pro-inflammatory phospho-signaling in human peripheral blood mononuclear cells treated with plasma from CVD patients, and caused an anti-inflammatory rewiring of macrophage populations. Our data highlight the relevance of pursuing Irg1 -itaconate axis supplementation as a therapeutic approach to treat atherosclerosis in humans.

Geniposide ameliorates atherosclerosis by restoring lipophagy via suppressing PARP1/PI3K/AKT signaling pathway

BackgroundAtherosclerosis (AS) is the leading cause of global death, which manifests as arterial lipid stack and plaque formation. Geniposide is an iridoid glycoside extract from Gardenia jasminoides J.Ellis that ameliorates AS by mediating autophagy. However, how Geniposide regulates autophagy and treats AS remains unclear. PurposeTo evaluate the efficacy and mechanism of Geniposide in treating AS.Study design and methods: Geniposide was administered to high-fat diet-fed ApoE−/− mice and oxidized low-density lipoprotein-incubated primary vascular smooth muscle cells (VSMCs). AS was evaluated with arterial lipid stack, plaque progression, and collagen loss in the artery. Foam cell formation was detected by lipid accumulation, inflammation, apoptosis, and the expression of foam cell markers. The mechanism of Geniposide in treating AS was assessed using network pharmacology. Lipophagy was measured by lysosomal activity, expression of lipophagy markers, and the co-localization of lipids and lipophagy markers. The effects of lipophagy were blocked using Chloroquine. The role of PARP1 was assessed by Olaparib (a PARP1 inhibitor) intervention and PARP1 overexpression. ResultsIn vivo, Geniposide reversed high-fat diet-induced hyperlipidemia, plaque progression, and inflammation. In vitro, Geniposide inhibited VSMC-derived foam cell formation by suppressing lipid stack, apoptosis, and the expressions of foam cell markers. Network pharmacological analysis and in vitro validation suggested that Geniposide treated AS by enhancing lipophagy via suppressing the PI3K/AKT signaling pathway. The benefits of Geniposide in alleviating AS were offset by Chloroquine in vivo and in vitro. Inhibiting PARP1 using Olaparib promoted lipophagy and alleviated AS progression, while PARP1 overexpression exacerbated foam cell formation and lipophagy blockage. The above effects of PARP1 were weakened by PI3K inhibitor LY294002. PARP1 also inhibited the combination of the ABCG1 and PLIN1. ConclusionGeniposide alleviated AS by restoring PARP1/PI3K/AKT signaling pathway-suppressed lipophagy. This study is the first to present the lipophagy-inducing effect of Geniposide and the binding of ABCG1 and PLIN1 inhibited by PARP1.

Glucagon-like Peptide-1 analogues and delipidation of coronary atheroma in statin-treated type 2 diabetic patients with coronary artery disease: The prespecified sub-analysis of the OPTIMAL randomized clinical trial

Background and aimsRandomized clinical trials have demonstrated the ability of glucagon-like peptide-1 analogues (GLP-1RAs) to reduce atherosclerotic cardiovascular disease events in patients with type 2 diabetes (T2D). How GLP-1RAs modulate diabetic atherosclerosis remains to be determined yet. MethodsThe OPTIMAL study was a prospective randomized controlled study to compare the efficacy of 48-week continuous glucose monitoring- and HbA1c-guided glycemic control on near infrared spectroscopty (NIRS)/intravascular ultrasound (IVUS)-derived plaque measures in 94 statin-treated patients with T2D (jRCT1052180152, UMIN000036721). Of these, 78 patients with evaluable serial NIRS/IVUS images were analyzed to compare plaque measures between those treated with (n = 16) and without GLP-1RAs (n = 72). ResultsAll patients received a statin, and on-treatment LDL-C levels were similar between the groups (66.9 ± 11.6 vs. 68.1 ± 23.2 mg/dL, p = 0.84). Patients receiving GLP-1RAs demonstrated a greater reduction of HbA1c [-1.0 (-1.4 to −0.5) vs. −0.4 (-0.6 to −0.2)%, p = 0.02] and were less likely to demonstrate a glucose level >180 mg/dL [-7.5 (-14.9 to −0.1) vs. 1.1 (-2.0 - 4.2)%, p = 0.04], accompanied by a significant decrease in remnant cholesterol levels [-3.8 (-6.3 to −1.3) vs. −0.1 (-0.8 - 1.1)mg/dL, p = 0.008]. On NIRS/IVUS imaging analysis, the change in percent atheroma volume did not differ between the groups (−0.9 ± 0.25 vs. −0.2 ± 0.2%, p = 0.23). However, GLP-1RA treated patients demonstrated a greater frequency of maxLCBI4mm regression (85.6 ± 0.1 vs. 42.0 ± 0.6%, p = 0.01). Multivariate analysis demonstrated that the GLP-1RA use was independently associated with maxLCBI4mm regression (odds ratio = 4.41, 95%CI = 1.19–16.30, p = 0.02). ConclusionsIn statin-treated patients with T2D and CAD, GLP-1RAs produced favourable changes in lipidic plaque materials, consistent with its stabilization.