Inhibits Atherosclerosis Progression Research Articles

M2 Macrophage-Derived Exosomes Inhibit Atherosclerosis Progression by Regulating the Proliferation, Migration, and Phenotypic Transformation of Smooth Muscle Cells.

Vascular smooth muscle cell (VSMC) intimal migration, proliferation, and phenotypic transformation from a contractile to a synthetic state are hallmarks of the progression of atherosclerotic plaques. This study aims to explore the effects of exosomes derived from M2 macrophages (ExoM2) on the pathological changes of VSMCs in atherosclerosis (AS). Cell Counting Kit-8 (CCK8) and wound healing assays were used to examine the impact of ExoM2 on platelet-derived growth factor-BB (PDGF-BB)-induced VSMC proliferation and migration, respectively. Western blotting was employed to analyze changes in the expression levels of contractile markers (e.g., alpha-smooth muscle actin [α-SMA]) and synthetic ones (e.g., osteopontin [OPN]) in VSMCs with or without ExoM2 treatment. ApoE-⁣/- mice on a high fat diet were utilized to observe the effects of ExoM2 on plaque progression and stability. Serial histopathological analysis was performed to elucidate the cellular mechanisms underlying the atheroprotective effects of ExoM2. Compared with controls, ExoM2 significantly inhibited PDGF-BB-induced VSMC proliferation, migration, and phenotypic transformation in vitro. In ApoE-⁣/- mice, ExoM2 treatment led to a marked reduction in plaque size, necrotic core area, the CD68/α-SMA ratio, and matrix metalloproteinase 9 (MMP9) and OPN levels, while enhancing plaque stability. ExoM2 inhibit AS progression by regulating VSMC proliferation, migration, and phenotypic transformation.

Baoyuan decoction inhibits atherosclerosis progression through suppression peroxidized fatty acid and Src/MKK4/JNK pathway-mediated CD 36 expression

Background: Baoyuan decoction (BYD) has been widely utilized as a traditional prescription for the treatment of various conditions such as coronary heart disease, aplastic anemia, and chronic renal failure. However, its potential efficacy in improving atherosclerosis has not yet been investigated.Purpose: Our research aimed to assess the potential of BYD as an inhibitor of atherosclerosis and uncover the underlying mechanism by which it acts on foam cell formation.Study Design and Methods: High-fat diet-induced ApoE-/- mice were employed to explore the effect of BYD on atherosclerosis. The differential metabolites in feces were identified and analyzed by LC-Qtrap-MS. In addition, we utilized pharmacological inhibition of BYD on foam cell formation induced by oxLDL in THP-1 cells to elucidate the underlying mechanisms specifically in macrophages.Results: The atherosclerotic plaque burden in the aortic sinus of ApoE-/- mice was notably reduced with BYD treatment, despite no significant alterations in plasma lipids. Metabolomic analysis revealed that BYD suppressed the increased levels of peroxidized fatty acids, specifically 9/13-hydroxyoctadecadienoic acid (9/13-HODE), in the feces of mice. As a prominent peroxidized fatty acid found in oxLDL, we confirmed that 9/13-HODE induced the overexpression of CD36 in THP-1 macrophages by upregulating PPARγ. In subsequent experiments, the decreased levels of CD36 triggered by oxLDL were observed after BYD treatment. This decrease occurred through the regulation of the Src/MMK4/JNK pathway, resulting in the suppression of lipid deposition in THP-1 macrophages.Conclusions: These results illustrate that BYD exhibits potential anti-atherosclerotic effects by inhibiting CD36 expression to prevent foam cell formation.

Associations Between Resolvin D1 and Culprit Plaque Morphologies: An Optical Coherence Tomography Study in Patients with ST-Segment Elevation Myocardial Infarction.

As a specialized pro-resolving lipid mediator, resolvin D1 (RvD1) inhibits atherosclerosis progression in vivo by reducing regional oxidative stress and chronic inflammation. However, it is unclear how RvD1 is involved in human coronary artery disease. This study aims to investigate the association between plasma levels of RvD1 and culprit-plaque characteristics in patients with ST-segment elevation myocardial infarction (STEMI). A total of 240 STEMI patients undergoing optical coherence tomography (OCT) examination were analyzed. RvD1 levels were measured in patient plasma samples using an enzyme-linked immunosorbent assay. Logistic regression was performed to assess the association between RvD1 levels and various culprit plaque morphologies, and the receiver operating curve was used to search for an optimal cutoff threshold to predict certain pathological features. The median RvD1 level was 129.7 (56.6-297.8) pg/mL. According to multivariable logistic regression, high RvD1 was associated with plaque rupture (≥111.5 pg/mL, odds ratio [OR]: 2.09, 95% confidence interval [CI]: 1.20-3.66, P = 0.010), healed plaques (≥246.4 pg/mL, OR: 2.17, 95% CI: 1.11-4.24, P = 0.023), and calcification (≥293.38 pg/mL, OR: 2.10, 95% CI: 1.21-3.66, P = 0.008) at culprit lesions. Increased levels of RvD1 were associated with higher instability of coronary atherosclerotic plaques in STEMI patients.

2-(2-Phenylethyl)chromone-enriched extract of Chinese agarwood (Aquilaria sinensis) inhibits atherosclerosis progression through endoplasmic reticulum stress-mediated CD36 expression in macrophages

Ethnopharmacological relevanceChinese agarwood, derived from the Aquilaria sinensis (Lour.) Gilg (Thymelaeaceae), has a long history of use in Traditional Chinese Medicine for the management of cardiovascular disease. However, the specific active ingredients responsible for its impact on atherosclerosis are yet to be fully understood.Aim of the study: The aim of this study is to investigate the anti-atherosclerotic effectiveness of the 2-(2-phenylethyl)chromone-enriched extract derived from Chinese agarwood (CPE) through the ER stress-mediated CD36 pathway. Materials and methodsTo assess the effectiveness of CPE, an atherosclerotic mouse model was established using ApoE−/− mice with a high-fat diet. Then we assessed the impact of CPE on lipid accumulation in THP-1 macrophages that were exposed to oxLDL. Subsequently, the effect of CPE on the expression of CD36 and markers related to ER stress was characterized. ResultsOur in vivo research confirmed that CPE effectively reduces the formation of aortic plaques in atherosclerotic ApoE−/− mice. Additionally, our in vitro study observed that CPE inhibits the uptake of oxLDL and hinders the generation of foam cells. This effect is achieved by downregulating the level of CD36 in macrophages. Furthermore, our study revealed that the increase in CD36 expression, resulting from oxLDL exposure, is governed by the activation of JNK1/2/3 signaling pathways and the initiation of ER stress. ConclusionCPE demonstrated significant efficacy to inhibit the atherosclerosis. The ER stress/P-JNK/PPARγ/CD36 signaling pathway plays critical involvement in modulating the foam cell formation in vitro and in vivo. These findings underscore the efficacy of CPE as a viable therapeutic intervention for the treatment of atherosclerosis.

Abstract 14158: Ceria/Iron Oxide and Silver/Iron Oxide Nanohybrids: New Classes of Materials for Theranostics of Cardiovascular Diseases

Introduction: The need for efficient and biocompatible treatment methods that can simultaneously deliver imaging and therapeutic agents for combined diagnosis and therapy have resulted in the development of theranostic nanoparticles in recent times. Nanotheranostics represent one of the last frontiers in precision medicine and provide real-time information about drug biodistribution, release, and targeted treatment in vivo. Hypothesis: Here we aim to develop biocompatible smart nanomaterials for efficient theranostics of cardiovascular diseases. Methods: We have developed various hybrid materials based on metal and metal oxide such as iron oxide, ceria, and silver for diagnosis and treatment of thrombosis, atherosclerosis and inflammatory diseases. Iron oxide offers magnetic resonance imaging (MRI) capability. Ceria provides antioxidant and anti-inflammatory effects. The incorporation of silver onto the particles not only provides photoacoustic imaging capability but also allows photothermal therapy. The developed nanohybrids were labelled with fluorescence molecules to enable optical imaging, and also tagged with targeting ligands for targeted delivery of the materials. Results: The ceria/iron oxide nanohybrids showed excellent theranostic property in a liver inflammation mouse model, and in an atherosclerosis model. MRI was successfully employed to monitor the delivery of the materials and detect the inflammation, and atherosclerosis. The particles could reverse liver inflammation and inhibit atherosclerosis progression while did not show any adverse effects systemically. The other nanohybrids, silver/iron oxide, exhibited multimodal imaging capability where both MRI and photoacoustic imaging could be used to image the materials and thus allowed the detection of thrombosis in mouse models. Triggered by 808nm light, the nanoparticles could induce excellent thrombolysis effect and completely restored blood flow in the clotted arteries. Interestingly, this material did not show any systemic adverse effect. Conclusions: Our data show that these new classes of materials are promising theranostic approaches for imaging and treating thrombosis and inflammation diseases such as atherosclerosis and liver inflammation.

Oxidized Phospholipid oxPAPC Alters Regulatory T-Cell Differentiation and Decreases Their Protective Function in Atherosclerosis in Mice.

Regulatory T cells (Tregs) are protective in atherosclerosis but reduced during disease progression due to cell death and loss of stability. However, the mechanisms of Treg dysfunction remain unknown. Oxidized phospholipids are abundant in atherosclerosis and can activate innate immune cells, but little is known regarding their impact on T cells. Given Treg loss during atherosclerosis progression and oxidized phospholipid levels in the plaque microenvironment, we investigated whether oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (oxPAPC), an oxidized phospholipid associated with atherosclerotic plaques, alters Treg differentiation and function. CD4+ T cells were polarized to Treg, T helper (Th) 1, and Th17 cells with or without oxPAPC and assessed by flow cytometry. Gene expression in oxPAPC-treated Tregs was analyzed by bulk RNA sequencing. Functional studies of oxPAPC-induced Tregs were performed by coculturing Tregs with CellTrace Violet-labeled cells in vitro, and by adoptively transferring Tregs to hyperlipidemic Ldlr-/- mice to measure atherosclerosis progression. Compared with controls, oxPAPC-treated Tregs were less viable, but surviving cells expressed higher levels of the Th1-associated markers T-bet, CXCR3, and IFN (interferon)-γ. Th1 and Th17 skewing cultures were unaltered by oxPAPC. IFN-γ is linked to Treg instability, thus Treg polarization experiments were repeated using Ifngr1-/- CD4+ T cells. IFNγR1 (INF gamma receptor 1) deficiency did not improve cell viability in oxPAPC-treated Tregs; however, T-bet and IFN-γ expression was not increased in surviving cells suggesting a role for IFN-γsignaling. OxPAPC-treated Tregs were less suppressive in vitro, and adoptive transfer studies in hyperlipidemic Ldlr-/- mice showed that oxPAPC-induced Tregs possessed altered tissue homing and were insufficient to inhibit atherosclerosis progression. OxPAPC elicits Treg-specific changes altering Treg differentiation and inducing a Th1-like phenotype in surviving cells partially through IFN-γ signaling. This is biologically relevant as oxPAPC-treated Tregs do not reduce atherosclerosis progression in Ldlr-/- mice. This study supports the role of oxidized phospholipids in negatively impacting Treg differentiation and atheroprotective function.

Oxidized phospholipid oxPAPC induces a dysfunctional Th1-like phenotype in regulatory T cells

Abstract Regulatory T cells (T regs) are protective in atherosclerosis but numbers are reduced during disease progression due to cell death and loss of stability. Oxidized lipids are abundant in atherosclerotic lesions and can activate innate immune cells, but there is limited information regarding their impact on T cells. Given the T regloss observed during atherosclerosis progression and increase in oxidized lipid levels in the microenvironment, we sought to determine whether an oxidized phospholipid associated with atherosclerosis, oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (oxPAPC), alters T regdifferentiation and function. In vitro skews of naïve T cells showed that oxPAPC-treated T regswere less viable with a greater proportion expressing the Th1 markers T-bet, CXCR3, and IFN-γ. Th1 and Th17 skewed cultures were unaltered by oxPAPC suggesting a T regspecific effect of oxPAPC. OxPAPC-treated T regswere less suppressive in vitro and were insufficient to inhibit atherosclerosis progression in an adoptive transfer in Ldlr −/−mice fed Western diet for up to 16 weeks. A role for IFN-γ signaling in T regdysregulation was examined using T regspecific IFNγR1 deficient mice. IFNγR1 deficient CD4 +T cells skewed in the presence of oxPAPC did not adopt the Th1-like T regphenotype compared to control oxPAPC-treated T regs, indicating that IFNγR signaling was important for oxPAPC-mediated T regdysregulation. Bone marrow transplant of Ldlr −/−showed that T regIFNγR1 signaling was atherogenic in males but protective in females. Overall, our findings demonstrate that oxidized phospholipids directly impact T regdifferentiation and decrease their atheroprotective potential.

Cover image

The cover image is based on the Original Article Melatonin inhibits atherosclerosis progression via galectin-3 downregulation to enhance autophagy and inhibit inflammation by Zitong Wang et al., https://doi.org/10.1111/jpi.12855.

Empagliflozin inhibits macrophage inflammation through AMPK signaling pathway and plays an anti-atherosclerosis role

ObjectiveIn recent years, some authoritative clinical studies have found that SGLT2 inhibitor can reduce cardiovascular risk in patients with diabetes, which may imply that SGLT2 inhibitor can play a role beyond lowering blood glucose. In this study, we explored the effect of empagliflozin on vascular atherosclerosis after removing the effect of diabetes. MethodsThe interaction between SGLT2 inhibitor and the AMPK(Adenosine 5′-monophosphate-activated protein kinase) signal pathway to attenuate atherosclerosis was studied in both spontaneously atherosclerotic mice in vivo and oxidized low-density lipoprotein(ox-LDL) induced macrophage inflammation model in vitro. In vivo experiment the aorta tree and aortic valve area were stained with oil red, and the level of inflammatory factors in the diseased tissue was evaluated by immunohistochemistry. Meanwhile, serum was collected to detect the levels of inflammatory factors. In vitro experiment, the RAW264.7 cell line was selected and ox-LDL was used to induce the release of proinflammatory factors, and different doses of empagliflozin were added. The phagocytosis of macrophages to ox-LDL density lipoprotein, and the expression of inflammatory factors at the protein and RNA levels were measured. ResultsEmpagliflozin reduced the area of atherosclerotic plaque and macrophage infiltration in atherosclerotic plaques, decreased the expression of inflammatory factors in local plaque tissues and serum of APOE−/− mice fed with high-fat diet. Empagliflozin can improve the protein expression level of p-AMPK affected by ox-LDL in cell and reduce the gene expression level of inflammatory factors and protein expression level of NF-κB, thus playing an anti-atherosclerosis role. ConclusionsEmpagliflozin improves energy metabolism and reduces the expression of inflammatory factors by activating AMPK. As empagliflozin inhibits atherosclerosis progression, it may be of use in prevention of cardiovascular diseases.

Exercise training inhibits atherosclerosis progression and reduces VE-cadherin levels within atherosclerotic plaques in hypercholesterolemic mice

Vascular endothelial-cadherin (VE-cadherin), matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) have emerged as key-factors of atherogenesis. The aim of this study was to evaluate the effects of exercise training (ET) on those key-factors in relation to the progression of atherosclerotic lesions in hypercholesterolemic mice. Thirty male, apoE knockout (apoE−/−) mice were randomly assigned to the following equivalent groups: 1) CO-control: High-fat diet (HFD) administration for 12 weeks. 2) EX-exercise: HFD administration as in CO, and during the last 4 weeks (9th −12th week) ET on treadmill (5sessions/week, 60min/session). At the end of study, blood samples were obtained and all mice were sacrificed. Aortic roots were excised and analysed regarding the percentage of aortic stenosis, and the relative concentrations of collagen, elastin, VE-cadherin, MMP-8,-9 and TIMP-1,-2 within the atherosclerotic lesions. Aortic stenosis was significantly lower in the EX than the CO group (39.63 ± 7.22% vs 62.04 ± 8.55%; p < 0.001), along with considerable increase in fibrous cap thickness and of collagen and elastin contents within plaques (p < 0.05). Compared to controls, exercised-treated mice showed reduced intra-plaque relative concentrations of VE-cadherin (15.09 ± 1.89% vs 23.49 ± 3.01%, p < 0.001), MMP-8 (8.51 ± 2.24% vs 18.51 ± 4.08%, p < 0.001) and MMP-9 (12.1 ± 4.86% vs 18.88 ± 6.23%, p < 0.001). Inversely, the relative concentrations of TIMP-1 and TIMP-2 in the ET group were considerably higher by 62.5% and 31.2% than in the EX group (p < 0.05), respectively. Finally, body weight and lipids concentrations did not differ between groups at the end of the study (p > 0.05). ET treatment induced regression of established atherosclerotic lesions in apoE−/− mice and improved their stability. Those effects seemed to be mediated by favourable modification of VE-cadherin, MMPs and TIMPs.

CircRNA-PTPRA Knockdown Inhibits Atherosclerosis Progression by Repressing ox-LDL-Induced Endothelial Cell Injury via Sponging of miR-671-5p.

Atherosclerosis (AS) is a chronic inflammatory disease with high morbidity and mortality rates worldwide. This study aimed to investigate the role of circular RNA protein tyrosine phosphatase receptor type A (circRNA_PTPRA) in oxidizedlow-densitylipoprotein (ox-LDL)-induced human umbilical vein endothelial cell (HUVECs) injury and its underlying molecular mechanism. The expression of circRNA-PTPRA and microRNA (miR)-671-5p was assessed by quantitative reverse transcription PCR (qRT-PCR). The interaction between circRNA-PTPRA and miR-671-5p was predicted using bioinformatic analysis. Cell viability and apoptosis were determined using the Cell Counting Kit-8 (CCK-8) assay and flow cytometry, respectively. Inflammation in HUVECs was analyzed by measuring the secretion of tumornecrosisfactoralpha (TNF-α), interleukin-1beta(IL-1β), and IL-6 using enzyme-linkedimmunosorbentassay(ELISA). Cleaved-caspase-3 expression was assessed using western blotting. The results indicated that circRNA-PTPRA expression was significantly increased and miR-671-5p expression was decreased in the serum of patients with AS and in ox-LDL-treated HUVECs. The interaction between circRNA-PTPRA and miR-671-5p was verified by dual luciferase reporter and RNA pull-down assays. In HUVECs, downregulation of circRNA-PTPRA reversed ox-LDL-induced reduction in cell viability, increase in apoptosis, and enhanced inflammation, whereas all these effects mediated by circRNA-PTPRA downregulation in ox-LDL-treated HUVECs were abolished by miR-671-5p downregulation. In conclusion, circRNA-PTPRA downregulation protects against ox-LDL-induced HUVECs injury by upregulating miR-671-5p, thereby providing potential therapeutic targets for AS.

Abstract 9186: Maslinic Acid Alleviates Atherosclerosis by Suppressing Mitochondrial ROS-Dependent NLRP3 Inflammasome Activation in Vascular Endothelial Cells via SIRT1/Nrf2 Pathway

Introduction: Maslinic acid (MA), a pentacyclic triterpenoid primarily found in food plants, has exhibited multiple inhibitory effects on proatherogenic factors, such as obesity, dyslipidemia, and inflammation. However, its effect on atherosclerosis remains unknown. In this study, we determined if MA can inhibit atherosclerosis progression and explored the underlying molecular mechanisms. Methods: To assess the anti-atherogenic effect of MA in vivo, ApoE deficient mice were treated with MA contained in high-fat diet for 16 weeks. After treatment, mouse aorta and serum samples were collected to determine atherosclerotic lesions, lipid profile, mitochondrial morphology and expression of related molecules. Additionally, human aortic endothelial cells (HAECs) were treated with ox-LDL to induce the endothelial injury model. Prior to the procedure, vehicle or MA were treated in the absence or presence of a SIRT1 inhibitor nicotinamide (NAM) and an Nrf2 inhibitor ML385. Concurrently, we investigated the effects and mechanisms of MA on mitochondrial dysfunction, oxidative stress injury and apoptosis in HAECs. Results: In vivo, MA conferred an anti-atherosclerotic effect as shown by reduced en face and aortic root sinus lesions size. From the electron microscopic analysis, MA ameliorated the mitochondrial damage in aortic endothelium. MA could promote the protein expression of SIRT1 and Nrf2, and enhance the expression of mitochondrial antioxidant enzymes. In addition, MA suppressed NLRP3 inflammasome activation to reduce apoptosis in vascular endothelium. In vitro, MA could inhibit ox-LDL-induced mitochondrial ROS generation by activating SIRT1/Nrf2 pathway, thereby inhibiting NLRP3 inflammasome activation and apoptosis in HAECs. NAM and ML385 eliminated the MA-mediated endothelial protective effect by restraining the expression of SIRT1 and Nrf2, respectively. Conclusions: In conclusion, our findings suggested that MA ameliorated endothelial apoptosis by suppressing mitochondrial ROS-dependent NLRP3 inflammasome activation via SIRT1/Nrf2 pathway and showed efficacy in exerting an anti-atherogenic effect.

Efficient aortic lymphatic drainage is necessary for atherosclerosis regression induced by ezetimibe

A functional lymphatic vasculature is essential for tissue fluid homeostasis, immunity, and lipid clearance. Although atherosclerosis has been linked to adventitial lymphangiogenesis, the functionality of aortic lymphatic vessels draining the diseased aorta has never been assessed and the role of lymphatic drainage in atherogenesis is not well understood. We develop a method to measure aortic lymphatic transport of macromolecules and show that it is impaired during atherosclerosis progression, whereas it is ameliorated during lesion regression induced by ezetimibe. Disruption of aortic lymph flow by lymphatic ligation promotes adventitial inflammation and development of atherosclerotic plaque in hypercholesterolemic mice and inhibits ezetimibe-induced atherosclerosis regression. Thus, progression of atherosclerotic plaques may result not only from increased entry of atherogenic factors into the arterial wall but also from reduced lymphatic clearance of these factors as a result of aortic lymph stasis. Our findings suggest that promoting lymphatic drainage might be effective for treating atherosclerosis.

Novel Autoimmune IgM Antibody Attenuates Atherosclerosis in IgM Deficient Low-Fat Diet-Fed, but Not Western Diet-Fed Apoe-/- Mice.

Oxidized phospholipids (OxPL), such as the oxidized derivatives of 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphorylcholine, 1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphorylcholine, and 1-palmitoyl-2-glutaroyl-sn-glycero-3-phosphorylcholine, have been shown to be the principal biologically active components of minimally oxidized LDL (low-density lipoprotein). The role of OxPL in cardiovascular diseases is well recognized, including activation of inflammation within vascular cells. Atherosclerotic Apoe-/- mice fed a high-fat diet develop antibodies to OxPL, and hybridoma B-cell lines producing natural anti-OxPL autoantibodies have been successfully generated and characterized. However, as yet, no studies have been reported demonstrating that treatment with OxPL neutralizing antibodies can be used to prevent or reverse advanced atherosclerosis. Approach and Results: Here, using a screening against 1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphorylcholine/1-palmitoyl-2-glutaroyl-sn-glycero-3-phosphorylcholine, we generated a novel IgM autoantibody, 10C12, from the spleens of Apoe-/- mice fed a long-term Western diet, that demonstrated potent OxPL neutralizing activity in vitro and the ability to inhibit macrophage accumulation within arteries of Apoe-/- mice fed a Western diet for 4 weeks. Of interest, 10C12 failed to inhibit atherosclerosis progression in Apoe-/- mice treated between 18 and 26 weeks of Western diet feeding likely due at least in part to high levels of endogenous anti-OxPL antibodies. However, 10C12 treatment caused a 40% decrease in lipid accumulation within aortas of secreted IgM deficient, sIgM-/-Apoe-/-, mice fed a low-fat diet, when the antibody was administrated between 32-40 weeks of age. Taken together, these results provide direct evidence showing that treatment with a single autoimmune anti-OxPL IgM antibody during advanced disease stages can have an atheroprotective outcome.

AIBP reduces atherosclerosis by promoting reverse cholesterol transport and ameliorating inflammation in apoE−/− mice

Background and aimsApoA-1 binding protein (AIBP) is a secreted protein that interacts with apoA-I and accelerates cholesterol efflux from cells. We have recently reported that AIBP promotes apoA-1 binding to ABCA1 in the macrophage cell membrane, partially through 115–123 amino acids. However, the effects of AIBP on the development of atherosclerosis in vivo remain unknown. MethodsApoE−/− mice with established atherosclerotic plaques were infected with rAAV-AIBP or rAAV-AIBP(Δ115-123), respectively. ResultsAIBP-treated mice showed reduction of atherosclerotic lesion formation, increase in circulating HDL levels and enhancement of reverse cholesterol transport to the plasma, liver, and feces. AIBP increased ABCA1 protein levels in aorta and peritoneal macrophages. Furthermore, AIBP could diminish atherosclerotic plaque macrophage content and the expression of chemotaxis-related factors. In addition, AIBP prevented macrophage inflammation by inactivating NF-κB and promoted the expression of M2 markers like Mrc-1 and Arg-1. However, lack of 115–123 amino acids of AIBP(Δ115-123) had no such preventive effects on the progression of atherosclerosis. ConclusionsOur observations demonstrate that AIBP inhibits atherosclerosis progression and suggest that it may be an effective target for prevention of atherosclerosis.

MiR-26a inhibits atherosclerosis progression by targeting TRPC3

BackgroundAtherosclerosis, a chronic multi-factorial vascular disease, has become a predominant cause of a variety of cardiovascular disorders. miR-26a was previously reported to be involved in atherosclerosis progression. However, the underlying mechanism of miR-26a in atherosclerosis remains to be further explained.MethodsHigh-fat diet (HFD)-fed apolipoprotein E (apoE)−/− mice and oxidized low-density lipoprotein (ox-LDL)-stimulated human aortic endothelial cells (HAECs) were established as in vivo and in vitro models of atherosclerosis. RT-qPCR and western blot analysis were performed to measure the expression of miR-26a and transient receptor potential canonical 3 (TRPC3), respectively. Binding between miR-26a and TRPC3 was predicted with bioinformatics software and verified using a dual luciferase reporter assay. The effects of miR-26a on the lipid accumulation, atherosclerotic lesion, and inflammatory response in HFD-fed apoE−/− mice were investigated by a colorimetric enzymatic assay system, hematoxylin–eosin and oil-Red-O staining, and ELISA, respectively. Additionally, the effects of miR-26a or combined with TRPC3 on cell viability, apoptosis and the nuclear factor-kappa B (NF-κB) pathway in ox-LDL-stimulated HAECs were evaluated by MTT assay, TUNEL assay, and western blot, respectively.ResultsmiR-26a was downregulated in HFD-fed apoE−/− mice and ox-LDL-stimulated HAECs. miR-26a overexpression inhibited the pathogenesis of atherosclerosis by attenuating hyperlipidemia, atherosclerotic lesion and suppressing inflammatory response in HFD-fed apoE−/− mice. Moreover, miR-26a overexpression suppressed inflammatory response and the NF-κB pathway, promoted cell viability and inhibited apoptosis in ox-LDL-stimulated HAECs. Additionally, TRPC3 was demonstrated to be a direct target of miR-26a. Enforced expression of TRPC3 reversed the effects of miR-26a on cell viability, apoptosis, and the NF-κB pathway in ox-LDL-treated HAECs.ConclusionsmiR-26a alleviated the development of atherosclerosis by regulating TRPC3, providing a potential target for atherosclerosis treatment.

The Pivotal Role of Thymus in Atherosclerosis Mediated by Immune and Inflammatory Response.

Atherosclerosis is one kind of chronic inflammatory disease, in which multiple types of immune cells or factors are involved. Data from experimental and clinical studies on atherosclerosis have confirmed the key roles of immune cells and inflammation in such process. The thymus as a key organ in T lymphocyte ontogenesis has an important role in optimizing immune system function throughout the life, and dysfunction of thymus has been proved to be associated with severity of atherosclerosis. Based on previous research, we begin with the hypothesis that low density lipoprotein or cholesterol reduces the expression of the thymus transcription factor Foxn1 via low density lipoprotein receptors on the membrane surface and low density lipoprotein receptor related proteins on the cell surface, which cause the thymus function decline or degradation. The imbalance of T cell subgroups and the decrease of naive T cells due to thymus dysfunction cause the increase or decrease in the secretion of various inflammatory factors, which in turn aggravates or inhibits atherosclerosis progression and cardiovascular events. Hence, thymus may be the pivotal role in coronary heart disease mediated by atherosclerosis and cardiovascular events and it can imply a novel treatment strategy for the clinical management of patients with atherosclerosis in addition to different commercial drugs. Modulation of immune system by inducing thymus function may be a therapeutic approach for the prevention of atherosclerosis. Purpose of this review is to summarize and discuss the recent advances about the impact of thymus function on atherosclerosis by the data from animal or human studies and the potential mechanisms.

Methotraxate-Loaded Hybrid Nanoconstructs Target Vascular Lesions and Inhibit Atherosclerosis Progression in ApoE-/- Mice.

Atherosclerosis is an inflammatory disorder characterized by the progressive thickening of blood vessel walls eventually resulting in acute vascular syndromes. Here, intravenously injectable hybrid nanoconstructs are synthesized for tempering immune cell inflammation locally and systemically. Lipid and polymer chains are nanoprecipitated to form 100 nm spherical polymeric nanoconstructs (SPNs), loaded with methotrexate (MTX) and subsequently labeled with Cu64 and fluorescent probes for combined nuclear/optical imaging. Upon engulfment into macrophages, MTX SPNs intracellularly release their anti-inflammatory cargo significantly lowering the production of proinflammatory cytokine (interleukin 6 and tumor necrosis factor α) already at 0.06 mg mL-1 of MTX. In ApoE-/- mice, fed with high-fat diet up to 17 weeks, nuclear and optical imaging demonstrates specific accumulation of SPNs within lipid-rich plaques along the arterial tree. Histological analyses confirm SPN uptake into macrophages residing within atherosclerotic plaques. A 4-week treatment with biweekly administration of MTX SPNs is sufficient to reduce the plaque burden in ApoE-/- mice by 50%, kept on high-fat diet for 10 weeks. Systemic delivery of MTX to macrophages via multifunctional, hybrid nanoconstructs constitutes an effective strategy to inhibit atherosclerosis progression and induce, potentially, the resorption of vascular lesions.

Moderate Autophagy Inhibits Vascular Smooth Muscle Cell Senescence to Stabilize Progressed Atherosclerotic Plaque via the mTORC1/ULK1/ATG13 Signal Pathway.

In order to investigate the effects of autophagy induced by rapamycin in the development of atherosclerosis plaque we established murine atherosclerosis model which was induced in ApoE−/− mice by high fat and cholesterol diet (HFD) for 16 weeks. Rapamycin and 3-Methyladenine (MA) were used as autophagy inducer and inhibitor respectively. The plaque areas in aortic artery were detected with HE and Oil Red O staining. Immunohistochemical staining were applied to investigate content of plaque respectively. In contrast to control and 3-MA groups, rapamycin could inhibit atherosclerosis progression. Rapamycin was able to increase collagen content and a-SMA distribution relatively, as well as decrease necrotic core area. Then we used MOVAS and culture with ox-LDL for 72 h to induce smooth muscle-derived foam cell model in vitro. Rapamycin and 3-MA were cultured together respectively. Flow cytometry assay and SA-β-Gal staining experiments were performed to detect survival and senescence of VSMCs. Western blot analysis were utilized to analyze the levels of protein expression. We found that rapamycin could promote ox-LDL-induced VSMCs autophagy survival and alleviate cellular senescence, in comparison to control and 3-MA groups. Western blot analysis showed that rapamycin could upregulate ULK1, ATG13 and downregulate mTORC1 and p53 protein expression.

Longxuetongluo capsule inhibits atherosclerosis progression in high-fat diet-induced ApoE−/− mice by improving endothelial dysfunction

Background and aimsChinese dragon's blood has been used to treat blood stasis for thousands of years. Its total phenolic extract (Longxuetongluo capsule, LTC) is used for the treatment of ischemic stroke; however, its protective effect against atherosclerosis remains poorly understood. This paper aims to investigate the antiatherosclerotic effect of LTC and the underlying mechanisms in high-fat diet (HFD)-induced ApoE−/− mice. MethodsThe levels of plasma lipid and areas of atherosclerotic lesions in the aortic sinus in ApoE−/− mice were evaluated. The effect of LTC on the nitric oxide (NO) production in oxidized low-density lipoprotein (ox-LDL)-stimulated human umbilical vein endothelial cells (HUVECs) was determined. The adhesion of monocytes to ox-LDL-stimulated HUVECs was further studied. ResultsLTC at low, medium, and high doses markedly decreased the atherosclerotic lesion areas of the aortic sinus in HFD-induced ApoE−/− mice by 26.4% (p < 0.05), 30.1% (p < 0.05), and 46.5% (p < 0.01), respectively, although it did not improve the dyslipidemia. Furthermore, LTC restored the diminished NO production of ox-LDL-stimulated HUVECs (p < 0.001) and inhibited the adhesion between monocytes and endothelial cells (p < 0.01). LTC appeared to alleviate ox-LDL-stimulated dysfunction of HUVECs, and inhibit the adhesion of monocytes to HUVECs via the MAPK/IKK/IκB/NF-κB signaling pathway, thus decrease atherosclerotic lesions in the aortic sinus in HFD-induced ApoE−/− mice. ConclusionsThese findings suggest the potential of LTC for use as an effective agent against atherosclerosis.