Inflammatory cytokines in atherosclerosis: current therapeutic approaches

Exploring the Relationship of Perivascular Adipose Tissue Inflammation and the Development of Vascular Pathologies

Initially thought to only provide mechanical support for the underlying blood vessels, perivascular adipose tissue (PVAT) has now emerged as a regulator of vascular function. A healthy PVAT exerts anticontractile and anti-inflammatory actions on the underlying vasculature via the release of adipocytokines such as adiponectin, nitric oxide, and omentin. However, dysfunctional PVAT produces more proinflammatory adipocytokines such as leptin, resistin, interleukin- (IL-) 6, IL-1β, and tumor necrosis factor-alpha, thus inducing an inflammatory response that contributes to the pathogenesis of vascular diseases. In this review, current knowledge on the role of PVAT inflammation in the development of vascular pathologies such as atherosclerosis and hypertension was discussed.

Higher serum level of CTRP15 in patients with coronary artery disease is associated with disease severity, body mass index and insulin resistance

BACKGROUND

CTRP15 is a prologue of adiponectin which has shown to have favourable effects on glucose and lipid metabolism. Studies have reported lower levels of CTRP15 in T2DM and metabolic syndrome; however, its circulating levels have not been evaluated in CAD patients.

METHODS

This case-control study was conducted on 190 angiographically confirmed coronary artery disease (CAD) patients and 70 controls. Serum levels of CTRP15, adiponectin, TNF-α, and IL-6 were measured using the ELISA technique.

RESULTS

CTRP15 was shown to occur in higher levels in CAD patients compared with controls. In CAD patients, CTRP15 showed a positive correlation with BMI, FBS, insulin, HOMA-IR, IL-6, and TNF-α and a negative correlation with HDL-C and adiponectin.

CONCLUSION

Elevated levels of CTRP15 in CAD patients and the relation of CTRP15 with pathogenic conditions such as insulin resistance, inflammation, and decreased adiponectin and HDL-C suggest a possible compensatory response to these conditions in CAD patients.

Therapeutic strategies targeting inflammation and immunity in atherosclerosis: how to proceed?

Atherosclerosis is a chronic inflammatory disease of the arterial wall, characterized by the formation of plaques containing lipid, connective tissue and immune cells in the intima of large and medium-sized arteries. Over the past three decades, a substantial reduction in cardiovascular mortality has been achieved largely through LDL-cholesterol-lowering regimes and therapies targeting other traditional risk factors for cardiovascular disease, such as hypertension, smoking, diabetes mellitus and obesity. However, the overall benefits of targeting these risk factors have stagnated, and a huge global burden of cardiovascular disease remains. The indispensable role of immunological components in the establishment and chronicity of atherosclerosis has come to the forefront as a clinical target, with proof-of-principle studies demonstrating the benefit and challenges of targeting inflammation and the immune system in cardiovascular disease. In this Review, we provide an overview of the role of the immune system in atherosclerosis by discussing findings from preclinical research and clinical trials. We also identify important challenges that need to be addressed to advance the field and for successful clinical translation, including patient selection, identification of responders and non-responders to immunotherapies, implementation of patient immunophenotyping and potential surrogate end points for vascular inflammation. Finally, we provide strategic guidance for the translation of novel targets of immunotherapy into improvements in patient outcomes.

In this Review, the authors provide an overview of the immune cells involved in atherosclerosis, discuss preclinical research and published and ongoing clinical trials assessing the therapeutic potential of targeting the immune system in atherosclerosis, highlight emerging therapeutic targets from preclinical studies and identify challenges for successful clinical translation.

Inflammation is an important component of the pathophysiology of cardiovascular disease; an imbalance between pro-inflammatory and anti-inflammatory processes drives chronic inflammation and the formation of atherosclerotic plaques in the vessel wall.

Clinical trials assessing canakinumab and colchicine therapies in atherosclerotic cardiovascular disease have provided proof-of-principle of the benefits associated with therapeutic targeting of the immune system in atherosclerosis.

The immunosuppressive adverse effects associated with the systemic use of anti-inflammatory drugs can be minimized through targeted delivery of anti-inflammatory drugs to the atherosclerotic plaque, defining the window of opportunity for treatment and identifying more specific targets for cardiovascular inflammation.

Implementing immunophenotyping in clinical trials in patients with atherosclerotic cardiovascular disease will allow the identification of immune signatures and the selection of patients with the highest probability of deriving benefit from a specific therapy.

Clinical stratification via novel risk factors and discovery of new surrogate markers of vascular inflammation are crucial for identifying new immunotherapeutic targets and their successful translation into the clinic.

Evaluation of Oxidative Stress Biomarkers, Pro-Inflammatory Cytokines, and Histological Changes in Experimental Hypertension, Dyslipidemia, and Type 1 Diabetes Mellitus

The present study aims to compare the oxidative stress biomarkers, pro-inflammatory cytokines, and histological changes induced by three cardiovascular risk factors, namely, hypertension, dyslipidemia, and type 1 diabetes mellitus. Hypertension was induced with 40 mg/kg body weight (b.w.) of N omega-nitro-L-arginine-methyl (L-NAME) administered orally. Dyslipidemia was induced by the administration of a diet with a high cholesterol (2%) content. Diabetes mellitus was induced by intraperitoneal administration of a single dose of streptozocin (65 mg/kg). Malondialdehyde (MDA) and total oxidative status (TOS) are increased by all three cardiovascular risk factors (up to 207%). The indirect assessment of NO synthesis (NOx) is observed to be reduced after L-NAME administration (43%), and dyslipidemia induction (16%), while type 1 diabetes mellitus is associated with the highest levels of NOx (increased 112%). Hypertension, dyslipidemia, and type 1 diabetes reduced the total antioxidative capacity (TAC) and total thiol (SH) levels (up to 57%). The values of evaluated pro-inflammatory cytokines, tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β), assessed from the ascending aorta were elevated by all three cardiovascular risk factors, with the highest levels induced by type 1 diabetes mellitus (up to 259%). The histopathological examination of the ascending and descending aorta revealed reversible pro-atherogenic changes consisting of the accumulation of lipid droplets in the subendothelial connective tissue on rats with hypertension and dyslipidemia. Irreversible pro-atherogenic changes consisting of a reduction of the specific elasticity of the arteries were observed in rats with type 1 diabetes mellitus. Type 1 diabetes mellitus demonstrates an alteration of the oxidative stress parameters, the elevation of tissue levels of the pro-inflammatory cytokines and causing irreversible pro-atherogenic changes on the aortic wall.

Nostoc flagelliforme capsular polysaccharides from different culture conditions improve hyperlipidemia and regulate intestinal flora in C57BL/6J mice to varying degrees

Two capsular polysaccharides (WL-CPS-1 and GLU-CPS-1) purified from Nostoc flagelliforme under normal and mixotrophic culture conditions were used to investigate the hypolipidemic activity and effect on intestinal flora in C57BL/6J mice respectively. Their molecular weight and monosaccharide composition have been determined in previous studies. They both improved the lipid level by affecting the expression of lipid metabolism genes. They down-regulated the TNF-α and IL-1β levels in serum and up-regulated the activity of antioxidant enzymes in liver thus decreased the atherosclerosis index and MDA content. They up-regulated the short chain fatty acids (SCFAs) synthesis. They decreased the abundance of pathogenic bacteria and increased the abundance of probiotics positively correlated with SCFAs. Compared with WL-CPS-1, GLU-CPS-1 exhibited higher in vivo activity and enriched Odoribacter and Alloprevotella correlating with the gene expression of lipid metabolism, suggesting that the bioactivity of polysaccharides could be regulated by culture conditions. These findings contributed to application of N. flagelliforme polysaccharides with higher activity in hypolipidemia by adjusting culture conditions.

Manipulating CD4+ T Cell Pathways to Prevent Preeclampsia

Preeclampsia (PreE) is a placental disorder characterized by hypertension (HTN), proteinuria, and oxidative stress. Individuals with PreE and their children are at an increased risk of serious short- and long-term complications, such as cardiovascular disease, end-organ failure, HTN, neurodevelopmental disorders, and more. Currently, delivery is the only cure for PreE, which remains a leading cause of morbidity and mortality among pregnant individuals and neonates. There is evidence that an imbalance favoring a pro-inflammatory CD4+ T cell milieu is associated with the inadequate spiral artery remodeling and subsequent oxidative stress that prime PreE's clinical symptoms. Immunomodulatory therapies targeting CD4+ T cell mechanisms have been investigated for other immune-mediated inflammatory diseases, and the application of these prevention tactics to PreE is promising, as we review here. These immunomodulatory therapies may, among other things, decrease tumor necrosis factor alpha (TNF-α), cytolytic natural killer cells, reduce pro-inflammatory cytokine production [e.g. interleukin (IL)-17 and IL-6], stimulate regulatory T cells (Tregs), inhibit type 1 and 17 T helper cells, prevent inappropriate dendritic cell maturation, and induce anti-inflammatory cytokine action [e.g. IL-10, Interferon gamma (IFN-γ)]. We review therapies including neutralizing monoclonal antibodies against TNF-α, IL-17, IL-6, and CD28; statins; 17-hydroxyprogesterone caproate, a synthetic hormone; adoptive exogenous Treg therapy; and endothelin-1 pathway inhibitors. Rebalancing the maternal inflammatory milieu may allow for proper spiral artery invasion, placentation, and maternal tolerance of foreign fetal/paternal antigens, thereby combatting early PreE pathogenesis.

Identification of Key Genes Associated with Endothelial Cell Dysfunction in Atherosclerosis Using Multiple Bioinformatics Tools

Atherosclerosis is the most notable cardiovascular disease, the latter being the main cause of death globally. Endothelial cell dysfunction plays a major role in the pathogenesis of atherosclerosis. However, it is currently unclear which genes are involved between endothelial cell dysfunction and atherosclerosis. This study was aimed at identifying these genes. Based on the GSE83500 dataset, the quantification of endothelial cell function was conducted using single-sample gene set enrichment analysis; the coexpression modules were conducted using weighted correlation network analysis. After building module-trait relationships, tan and yellow modules were regarded as hub modules. 10 hub genes from each hub module were identified by the protein-protein interaction network analysis. The key genes (RAB5A, CTTN, ITGB1, and MMP9) were obtained by comparing the expression differences of the hub gene between atherosclerotic and normal groups from the GSE28829 and GSE43292 datasets, respectively. ROC analysis showed the diagnostic value of key genes. Moreover, the differential expression of key genes in normal and atherosclerotic aortic walls was verified. In vitro, we establish a model of ox-LDL-injured endothelial cells and transfect RAB5A overexpression and shRNA plasmids. The results showed that overexpression of RAB5A ameliorates the proliferation and migration function of ox-LDL-injured endothelial cells, including the ability of tubule formation. It was speculated that the interferon response, Notch signaling pathways, etc. were involved in this function of RAB5A by using gene set variation analysis. With the multiple bioinformatics analysis methods, we detected that yellow and tan modules are related to the abnormal proliferation and migration of endothelial cells associated with atherosclerosis. RAB5A, CTTN, ITGB1, and MMP9 can be used as potential targets for therapy and diagnostic markers. In vitro, overexpression of RAB5A can ameliorate the proliferation and migration function of ox-LDL-injured endothelial cells, and the possible molecules involved in this process were speculated.

Deficiency of inactive rhomboid protein 2 (iRhom2) attenuates diet-induced hyperlipidaemia and early atherogenesis

AIMS

Atherosclerosis is a chronic inflammatory disease of the arterial vessel wall and anti-inflammatory treatment strategies are currently pursued to lower cardiovascular disease burden. Modulation of recently discovered inactive rhomboid protein 2 (iRhom2) attenuates shedding of tumour necrosis factor-alpha (TNF-α) selectively from immune cells. The present study aims at investigating the impact of iRhom2 deficiency on the development of atherosclerosis.

METHODS AND RESULTS

Low-density lipoprotein receptor (LDLR)-deficient mice with additional deficiency of iRhom2 (LDLR-/-iRhom2-/-) and control (LDLR-/-) mice were fed a Western-type diet (WD) for 8 or 20 weeks to induce early or advanced atherosclerosis. Deficiency of iRhom2 resulted in a significant decrease in the size of early atherosclerotic plaques as determined in aortic root cross-sections. LDLR-/-iRhom2-/- mice exhibited significantly lower serum levels of TNF-α and lower circulating and hepatic levels of cholesterol and triglycerides compared to LDLR-/- mice at 8 weeks of WD. Analyses of hepatic bile acid concentration and gene expression at 8 weeks of WD revealed that iRhom2 deficiency prevented WD-induced repression of hepatic bile acid synthesis in LDLR-/- mice. In contrast, at 20 weeks of WD, plaque size, plaque composition, and serum levels of TNF-α or cholesterol were not different between genotypes.

CONCLUSION

Modulation of inflammation by iRhom2 deficiency attenuated diet-induced hyperlipidaemia and early atherogenesis in LDLR-/- mice. iRhom2 deficiency did not affect diet-induced plaque burden and composition in advanced atherosclerosis in LDLR-/- mice.

Key Roles of Inflammation in Atherosclerosis: Mediators Involved in Orchestrating the Inflammatory Response and Its Resolution in the Disease Along with Therapeutic Avenues Targeting Inflammation

Inflammation is a critical driver of all stages of atherosclerosis, from lesion development to plaque rupture. Cytokines are mediators of the immune response and in atherosclerosis, the balance of anti- and pro-inflammatory cytokines is tipped in favor of the latter, resulting in persistent and unresolved inflammation. Although reducing plasma cholesterol levels mainly via the use of statins has positively impacted patient outcomes and reduced mortality rates, the presence of significant residual inflammation and cardiovascular risk posttherapy emphasizes the prevailing risk of primary and secondary events driven by inflammation independently of hyperlipidemia. Given the dominant role of inflammation in driving pathogenesis, alternative therapeutic avenues beyond targeting lowering of plasma lipids are required. This chapter will discuss the role of inflammation and pro-inflammatory cytokines in driving atherogenesis and disease progression, the therapeutic potential of targeting cytokines for atherosclerosis and promising avenues in this area.

Sitagliptin Attenuates the Cognitive Deficits in L-Methionine-Induced Vascular Dementia in Rats

Vascular dementia (VaD) is the second most prevalent type of dementia characterized by progressive cognitive deficits and is a major risk factor for the development of Alzheimer's disease and other neurodegenerative disorders. This study is aimed at determining the potential neuroprotective effect of sitagliptin (STG) on cognitive deficits in L-methionine-induced VaD in rats and the possible underlying mechanisms. 30 adult male Wistar albino rats were divided equally (n = 10) into three groups: control, VaD, and VaD + STG groups. The cognitive performance of the animals was conducted by open field, elevated plus maze, Y-maze, novel object recognition, and Morris water maze tests. Serum homocysteine, TNF-α, IL-6, IL-10, total cholesterol, and triglycerides levels were assessed together with hippocampal MDA, SOD, and BDNF. Histopathological and immunohistochemical assessments of the thoracic aorta and hippocampus (CA1 region) were also performed. Chronic L-methionine administration impaired memory and learning and induced anxiety. On the other hand, STG protected against cognitive deficits through improving oxidative stress biomarkers, inflammatory mediators, lipid profiles, and hippocampus level of BDNF as well as decreasing caspase-3 and GFAP and increasing Ki-67 immunoreactions in the hippocampus. Also, STG improved the endothelial dysfunction via upregulation of aortic eNOS immunoreaction. STG improved the cognitive deficits of L-methionine-induced VaD by its antioxidant, anti-inflammatory, antiapoptotic, and neurotrophic effects. These findings suggest that STG may be a promising future agent for protection against VaD.

Identification of heterogeneous subsets of aortic interleukin-17A-expressing CD4+ T cells in atherosclerotic mice

Objectives: T helper 17 (Th17) cells are involved in the inflammatory response of atherosclerosis. However, their heterogeneity in the atherosclerotic aorta remains elusive. This study was designed to identify aortic Th17 subsets. Methods: The surface markers and transcription factors of aortic interleukin-17A (IL-17A)-expressing T cells were determined by flow cytometry in an ApoE-deficient mouse atherosclerotic model. Viable aortic IL-17A-expressing T cell subsets were isolated by flow cytometry on the basis of surface markers, followed by characterizing their transcription factors by either flow cytometry or real-time RT-PCR. The effect of aortic IL-17A-expressing T cell subsets on aortic endothelial cells was determined in vitro. Results: C-X-C Motif Chemokine Receptor 3 (CXCR3), interleukin-17 receptor E (IL-17RE), CD200, and C-C Motif Chemokine Receptor 4 (CCR4) marked three subsets of aortic IL-17A-expressing T cells: CXCR3⁺IL-17RE^lowCD200⁺CCR4^- T cells expressing T-box protein expressed in T cells (T-bet) and interferon-gamma (IFN-γ), CXCR3⁺IL-17RE^lowCD200⁺CCR4⁺ T cells expressing T-bet but fewer IFN-γ, and CXCR3⁻IL-17RE^highCD200⁺CCR4⁺ T cells expressing very low T-bet and no IFN-γ. Based on these markers, viable aortic Th17 cells, Th17.1 cells, and transitional Th17.1 cells were identified. Both Th17.1 cells and transitional Th17.1 cells were more proliferative than Th17 cells. Compared with Th17 cells, Th17.1 cells plus transitional Th17.1 cells induced higher expression of C-X-C motif chemokine ligand 1 (CXCL1), C-C motif chemokine ligand 2 (CCL2), C-X-C motif chemokine 5 (CXCL5), and granulocyte-macrophage colony-stimulating factor (GM-CSF) in aortic endothelial cells. Conclusion: IL-17A-expressing CD4⁺ T cells were heterogeneous in atherosclerotic aortas.

Guanxinkang Decoction Attenuates the Inflammation in Atherosclerosis by Regulating Efferocytosis and MAPKs Signaling Pathway in LDLR-/- Mice and RAW264.7 Cells

Guanxinkang decoction (GXK), a traditional Chinese medicinal drug, is used to treat cardiovascular disease. The aim of the study was to investigate the effects of GXK on inflammation in LDLR^−/− mice and RAW264.7 cells. Fed with high fat diet for 12 weeks, the mice were randomly divided into six groups, then administered with oral 0.9% saline or GXK (7.24, 14.48, and 28.96 g/kg) or Atorvastatin (1.3 mg/kg) for 12 weeks. RAW 264.7 cells were induced with ox-LDL or ox-LDL plus different concentrations of GXK (1.25, 2.5, and 5 μg/ml), or ox-LDL plus GXK plus MAPKs activators. Serum lipid profiles and inflammatory cytokines were detected by ELISA, gene expression by RT-qPCR, plaque sizes by Oil Red O, α-SMA, caspase 3, NF-κB p65 and TNF-α production by immunofluorescence staining, and protein expression by Western Blot. The phagocytic ability of cells was determined by neutral red uptake assay. Efferocytosis-related proteins (AML, MERTK, TYRO3 and MFGE8) and MAPKs pathways were detected by Western Blot. Compared to mice fed with high fat diet, the mice with GXK showed lower cholesterol, triglyceride, low-density lipoprotein cholesterol, IL-1β, IL-6, and TNF-α, smaller plaque sizes, higher α-SMA, and lower caspase 3 and NF-κB p65 in aortic roots. RAW264.7 cells treated with ox-LDL plus GXK had lower IL-1β, IL-6, and TNF-α. GXK also increased the phagocytic ability of cells. High levels of AML, MERTK, TYRO3 and MFGE8, and decreased levels of iNOS, VCAM-1, LOX-1 and MCP-1, and phosphorylation of ERK1/2, JNK, p38, and NF-κB were detected in GXK-treated group. MAPKs activators reversed the effects of GXK in repressing inflammation and promoting phagocytosis. These results suggested that GXK could attenuate atherosclerosis and resolve inflammation via efferocytosis and MAPKs signaling pathways in LDLR^−/− mice and RAW264.7 cells.

Treatment of Cardiovascular Disease in Rheumatoid Arthritis: A Complex Challenge with Increased Atherosclerotic Risk

Rheumatoid arthritis (RA) carries significant risk for atherosclerotic cardiovascular disease (ASCVD). Traditional ASCVD risk factors fail to account for this accelerated atherosclerosis. Shared inflammatory pathways are fundamental in the pathogenesis of both diseases. Considering the impact of RA in increasing cardiovascular morbidity and mortality, the characterization of therapies encompassing both RA and ASCVD management merit high priority. Despite little progress, several drugs discussed here promote remission and or lower rheumatoid disease activity while simultaneously conferring some level of atheroprotection. Methotrexate, a widely used disease-modifying drug used in RA, is associated with significant reduction in cardiovascular adverse events. MTX promotes cholesterol efflux from macrophages, upregulates free radical scavenging and improves endothelial function. Likewise, the sulfonamide drug sulfasalazine positively impacts the lipid profile by increasing HDL-C, and its use in RA has been correlated with reduced risk of myocardial infraction. In the biologic class, inhibitors of TNF-α and IL-6 contribute to improvements in endothelial function and promote anti-atherogenic properties of HDL-C, respectively. The immunosuppressant hydroxychloroquine positively affects insulin sensitization and the lipid profile. While no individual therapy has elicited optimal atheroprotection, further investigation of combination therapies are ongoing.

Biological and clinical implications of TNF-α promoter and CYP1B1 gene variations in Coronary Artery Disease susceptibility

BACKGROUND

Cardiovascular diseases (CVD) are important causes of death worldwide. Atherosclerosis is a chronic inflammatory disorder. It is the major cause of CVD and is manifested by ischemic heart disease or coronary artery disease (CAD). TNF-α is a pro-inflammatory cytokine that regulates immune response and promotes the development of atherosclerosis. Cytochrome p450 1B1 (CYP1B1) is an enzyme involved in the metabolism of endogenous and exogenous substrates.

OBJECTIVES

This study aimed at examining the association of TNF-α rs1800629 G >A and CYP1B1 rs1056827 G>T gene polymorphisms with CAD susceptibility in an Indian cohort.

METHODS

AS-PCR and direct DNA sequencing were used to examine the association of TNF-α rs1800629 G >A and CYP1B1 rs1056827 G>T gene polymorphism with CAD in an Indian cohort. A total of 100 clinically confirmed cases of CAD and 110 matched apparently healthy controls were genotyped.

RESULTS

Allelic and genotypic frequencies did not deviate from Hardy-Weinberg equilibrium in the controls (p>0.05) for TNF-α G-308A and CYP1B1 rs1056827G>A. There was no significant difference between the TNF-α rs1800629 A>G genotype distribution between cases and controls (P-value >0.05). A significant difference was observed between the CYP1B1 rs1056827 G>T genotype distribution between CAD cases and controls (P<0.0003). Our result indicated that in the codominant model, the GA genotype of the CYP1B1 rs1056827 G>T was associated with CAD with OR= 2.21(1.17 to 4.15), RR=1.38(1.07 to 1.78), and P<0.013. In the dominant model, the (GA+AA) genotype was associated with CAD with OR=2.79(1.54 to 5.05) and P<0.007. The CYP1B1 rs1056827 'A' allele was associated with CAD with OR = 2.30 (1.55 to 3.42) and P< 0.0001. Our results indicated that TNF-α 1800629 gene polymorphism was strongly associated with hypercholesteremia (P<0.0009), HDL (P<0.0001), TGL (P<0.039), hypertension (P<0.0001), and smoking (P<0.0001) in patients with Coronary Artery Disease. Similar correlations of CYP1B1 rs1056827 genotypes were reported with cholesterol (P<0.020), HDL (P<0.002), LDL (P<0.006), hypertension (P<0.03), and smoking (P<0.005).

CONCLUSION

It was reported that the GA genotype of the CYP1B1 rs1056827 G>T was strongly associated with susceptibility to Coronary Artery Disease with OR= 2.21(1.17 to 4.15)) and P<0.013, and similarly, its A allele was associated with predisposition to CAD with OR = 2.30(1.55 to 3.42) and P< 0.0001. Our results indicated that TNF-α 1800629 gene polymorphism is not associated with predisposition to Coronary Artery Disease. Nevertheless, these results should be taken with caution and further validated with larger-scale studies before being introduced in the clinical setting.

CRISPR/Cas9-mediated knockout of APOC3 stabilizes plasma lipids and inhibits atherosclerosis in rabbits

Background

High levels of apolipoprotein C3 (APOC3) can lead to hypertriglyceridemia, which increases the risk of cardiovascular disease. We aim to create APOC3-knockout (KO) rabbits and explore the effects of APOC3 deletion on the occurrence and development of atherosclerosis.

Methods

An sgRNA anchored to exon 2 of APOC3 was designed to edit embryo genomes using the CRISPR/Cas9 system. The founder rabbits were sequenced, and their lipid profile, inflammatory cytokines, and atherosclerotic plaques were analyzed.

Results

When given a normal chow (NC) diet, all APOC3-KO rabbits had 50% lower triglyceride (TG) levels than those of the matched age control group. Additionally, their plasma lipoprotein lipase increased. When fed a high-fat diet, APOC3 deficiency was observed to be more conducive to the maintenance of plasma TG, total cholesterol, and low-density lipoprotein cholesterol levels, and the inhibition of the inflammatory response and the protection against atherosclerosis in rabbits.

Conclusion

APOC3 deficiency can delay the formation of atherosclerosis-induced HFD in rabbits, indicating this is a novel therapeutic target to treat atherosclerosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-021-01605-7.

Beneficial effects of cinnamon and its extracts in the management of cardiovascular diseases and diabetes

Cardiovascular diseases (CVDs) and diabetes are the leading causes of death worldwide, which underlines the urgent necessity to develop new pharmacotherapies. Cinnamon has been an eminent component of spice and traditional Chinese medicine for thousands of years. Numerous lines of findings have elucidated that cinnamon has beneficial effects against CVDs in various ways, including endothelium protection, regulation of immune response, lowering blood lipids, antioxidative properties, anti-inflammatory properties, suppression of vascular smooth muscle cell (VSMC) growth and mobilization, repression of platelet activity and thrombosis and inhibition of angiogenesis. Furthermore, emerging evidence has established that cinnamon improves diabetes, a crucial risk factor for CVDs, by enhancing insulin sensitivity and insulin secretion; regulating the enzyme activity involved in glucose; regulating glucose metabolism in the liver, adipose tissue and muscle; ameliorating oxidative stress and inflammation to protect islet cells; and improving diabetes complications. In this review, we summarized the mechanisms by which cinnamon regulates CVDs and diabetes in order to provide a theoretical basis for the further clinical application of cinnamon.

Clinical- and omics-based models of subclinical atherosclerosis in healthy Chinese adults: a cross-sectional exploratory study

BACKGROUND

Classical risk factors, such as fasting cholesterol, blood pressure (BP), and diabetes status are used today to predict the risk of developing cardiovascular disease (CVD). However, accurate prediction remains limited, particularly in low-risk groups such as women and younger individuals. Growing evidence suggests that biomarker concentrations following consumption of a meal challenge are better and earlier predictors of disease development than biomarker concentrations.

OBJECTIVE

To test the hypothesis that postprandial responses of circulating biomarkers differ between healthy subjects with and without subclinical atherosclerosis (SA) in an Asian population at low risk of coronary artery disease (CAD).

METHODS

One hundred healthy Chinese subjects (46 women, 54 men) completed the study. Subjects consumed a mixed-meal test and 164 blood biomarkers were analyzed over 6 h by using a combination of chemical and NMR techniques. Models were trained using different methodologies (including logistic regression, elastic net, random forest, sparse partial least square) on a random 75% subset of the data, and their performance was evaluated on the remaining 25%.

RESULTS

We found that models based on baseline clinical parameters or fasting biomarkers could not reliably predict SA. By contrast, an omics model based on magnitude and timing of postprandial biomarkers achieved high performance [receiving operating characteristic (ROC) AUC: 91%; 95% CI: 77, 100). Investigation of key features of this model enabled derivation of a considerably simpler model, solely based on postprandial BP and age, with excellent performance (AUC: 91%; 95% CI: 78, 100).

CONCLUSION

We report a novel model to detect SA based on postprandial BP and age in a population of Asian subjects at low risk of CAD. The use of this model in large-scale CVD prevention programs should be explored. This trial was registered at ClinicalTrials.gov as NCT03531879.

The Effect of Homocysteine on the Secretion of Il-1β, Il-6, Il-10, Il-12 and RANTES by Peripheral Blood Mononuclear Cells-An In Vitro Study

The contemporary theory of the inflammatory-immunological pathomechanism of atherosclerosis includes the participation of interleukin-1β (Il), Il-6, Il-10, Il-12, RANTES, and homocysteine in this process. The knowledge on the direct effect of hyperhomocysteinemia on inflammatory-state-related atherosclerosis is rather scarce. Our study is the first to account for the effects of homocysteine on the secretion of Il-10 and RANTES in vitro conditions. For this purpose, human mitogen-stimulated peripheral blood mononuclear cells (PBMNCs) were cultured in vitro and exposed to homocysteine at high concentrations. Subsequently, the concentrations of cytokines were assayed in the cell culture supernatant using flow cytofluorimetry. It has been shown that, in the presence of homocysteine, the secretion of IL-1, IL-6 and RANTES by PBMNCs was increased, whereas IL-10 concentration was significantly lower than that of the supernatant derived from a mitogen-stimulated cell culture without homocysteine. The secretion of Il-12 by PBMNCs exposed exclusively to mitogen, did not differ from homologous cells also treated with homocysteine. Therefore, in our opinion, high-concentration homocysteine affects the progression of atherosclerosis by increasing the secretion of proinflammatory cytokines secreted by PBMNCs, such as Il-1β, Il-6, RANTES, and by attenuating the secretion of Il-10.

Circ_USP36 Silencing Attenuates Oxidized Low-Density Lipoprotein-Induced Dysfunction in Endothelial Cells in Atherosclerosis Through Mediating miR-197-3p/ROBO1 Axis

ABSTRACT

Circular RNAs (circRNAs) are reported to play pivotal regulatory roles in atherosclerosis progression. In the present study, we explored the biological role of circRNA ubiquitin-specific peptidase 36 (circ_USP36; hsa_circ_0003204) in oxidized low-density lipoprotein (ox-LDL)-induced dysfunction of endothelial cells (ECs). RNA and protein levels were determined by reverse transcription-quantitative polymerase chain reaction and Western blot assay, respectively. Cell proliferation was analyzed by 5-ethynyl-2'-deoxyuridine assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Flow cytometry was conducted to analyze cell cycle progression and cell apoptosis. The release of tumor necrosis factor α in the supernatant was measured by enzyme linked immunosorbent assay. Cell death was evaluated by lactate dehydrogenase assay. Intermolecular interaction was verified by dual-luciferase reporter assay. Circ_USP36 expression was significantly up-regulated in the serum of atherosclerosis patients and ox-LDL-stimulated HUVECs than that in their corresponding controls. ox-LDL exposure inhibited the proliferation ability and cell cycle progression and triggered the apoptosis and inflammation of HUVECs, and these effects were largely overturned by the knockdown of circ_USP36. microRNA-197-3p (miR-197-3p) was a target of circ_USP36, and circ_USP36 knockdown-mediated protective role in ox-LDL-induced HUVECs was largely counteracted by the silence of miR-197-3p. miR-197-3p interacted with the 3' untranslated region of roundabout guidance receptor 1 (ROBO1). Circ_USP36 knockdown reduced ROBO1 expression partly by up-regulating miR-197-3p in HUVECs. ROBO1 overexpression reversed miR-197-3p accumulation-mediated effects in ox-LDL-induced HUVECs. In conclusion, circ_USP36 interference alleviated ox-LDL-induced dysfunction in HUVECs by targeting miR-197-3p/ROBO1 axis.

Formation and Cellular Impact of Cholesterol Crystals in Health and Disease

Cholesterol crystals (CCs) were first discovered in atherosclerotic plaque tissue in the early 1900 and have since been observed and implicated in many diseases and conditions, including myocardial infarction, abdominal aortic aneurism, kidney disease, ocular diseases, and even central nervous system anomalies. Despite the widespread involvement of CCs in many pathologies, the mechanisms involved in their formation and their role in various diseases are still not fully understood. Current knowledge concerning the formation of CCs, as well as the molecular pathways activated upon cellular exposure to CCs, will be explored in this review. As CC formation is tightly associated with lipid metabolism, the role of cellular lipid homeostasis in the formation of CCs is highlighted, including the role of lysosomes. In addition, cellular pathways and processes known to be affected by CCs are described. In particular, CC-induced activation of the inflammasome and production of reactive oxygen species, along with the role of CCs in complement-mediated inflammation is discussed. Moreover, the clinical manifestation of embolized CCs is described with a focus on renal and skin diseases associated with CC embolism. Lastly, potential therapeutic measures that target either the formation of CCs or their impact on different cell types and tissues are highlighted.

Risk of acute atherosclerotic cardiovascular disease in patients with acute and chronic pancreatitis

The association between pancreatitis and acute myocardial infarction or stroke remains incompletely understood. This study aimed to evaluate the long-term risk of acute atherosclerotic cardiovascular disease (ASCVD) in people with acute and chronic pancreatitis. Using research database of Taiwan's National Health Insurance, we identified 2678 patients aged ≥ 20 years with newly diagnosed pancreatitis in 2000–2008. A cohort of 10,825 adults without pancreatitis was selected for comparison, with matching by age and sex. Both cohorts were followed from 2000 to the end of 2013, and incident acute ASCVD was identified during the follow-up period. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of acute ASCVD associated with pancreatitis were calculated. Compared with the comparison cohort, the adjusted HR of acute ASCVD were 1.76 (95% CI 1.47–2.12) and 3.42 (95% CI 1.69–6.94) for people with acute pancreatitis and chronic pancreatitis, respectively. A history of alcohol-related illness (HR 9.49, 95% CI 3.78–23.8), liver cirrhosis (HR 7.31, 95% CI 1.81–29.5), and diabetes (HR 6.89, 95% CI 2.18–21.8) may worsen the risk of acute ASCVD in patients with chronic pancreatitis. Compared with people had no pancreatitis, patients with acute pancreatitis who had alcohol-related illness (HR 4.66, 95% CI 3.24–6.70), liver cirrhosis (HR 4.44, 95% CI 3.05–6.47), and diabetes (HR 2.61, 95% CI 2.03–3.36) were at increased risk of acute ASCVD. However, the cumulative use of metformin was associated with a reduced risk of acute ASCVD in the acute pancreatitis cohort (HR 0.30, 95% CI 0.17–0.50). Compared with the control group, patients with acute or chronic pancreatitis were more likely to have an increased risk of acute ASCVD, while the use of metformin reduced the risk of acute ASCVD. Our findings warrant a survey and education on acute ASCVD for patients with acute and chronic pancreatitis.

The Role of Bamboo Shoot Gigantochloa Apus Extract in Decreasing the IL-17/IL-10 Ratio Level in the Atherosclerosis Process

BACKGROUND: Atherosclerosis begins with injury to the endothelial, progressive, and increases by 3% per year since the age of a person passes 20 years. The ratio of the number of pro and anti-inflammatory cytokines can describe the development of the process of atherosclerosis so that the higher the ratio will increase the chance of atherosclerosis. AIM: The purpose of this study was to examine the effect of Bamboo shoot Gigantochloa apus (BSGA) extract on decreasing interleukin-17 (IL-17)/IL-10 level ratios in New Zealand White rabbits given an atherogenic diet. METHODS: This study uses BSGA extract freeze-dried aged 1–2 weeks and New Zealand White rabbits. Atherogenic feed uses 0.5% egg yolk and 5% pork oil which is added to the standard feed. Randomized pre- and post-test with control group design by dividing into four groups were used in this study. RESULTS: The mean ratio of IL-17 levels with IL-10 between before and after (p < 0.005) in all groups showed a significant difference. There was a trend of increasing the ratio between IL-17 levels and IL-10 in all groups and the highest increase occurred in the control group which was 420%. CONCLUSION: The higher the dose of BSGA extract administration could reduce the ratio between IL-17 levels and IL-10 and there is a correlation with a negative linear pattern between IL-10 and IL-17 with p = 0.034 which means that higher levels of IL-10 will reduce IL-17 levels.

Inflammatory Mediators of Platelet Activation: Focus on Atherosclerosis and COVID-19

Background: Atherosclerotic cardiovascular diseases are characterized by a dysregulated inflammatory and thrombotic state, leading to devastating complications with increased morbidity and mortality rates. Summary: In this review article, we present the available evidence regarding the impact of inflammation on platelet activation in atherosclerosis. Key messages: In the context of a dysfunctional vascular endothelium, structural alterations by means of endothelial glycocalyx thinning or functional modifications through impaired NO bioavailability and increased levels of von Willebrand factor result in platelet activation. Moreover, neutrophil-derived mediators, as well as neutrophil extracellular traps formation, have been implicated in the process of platelet activation and platelet-leukocyte aggregation. The role of pro-inflammatory cytokines is also critical since their receptors are also situated in platelets while TNF-α has also been found to induce inflammatory, metabolic, and bone marrow changes. Additionally, important progress has been made towards novel concepts of the interaction between inflammation and platelet activation, such as the toll-like receptors, myeloperoxidase, and platelet factor-4. The accumulating evidence is especially important in the era of the coronavirus disease-19 pandemic, characterized by an excessive inflammatory burden leading to thrombotic complications, partially mediated by platelet activation. Lastly, recent advances in anti-inflammatory therapies point towards an anti-thrombotic effect secondary to diminished platelet activation.

Sensing Inflammation Biomarkers with Electrolyte-Gated Organic Electronic Transistors

An overview of cytokine biosensing is provided, with a focus on the opportunities provided by organic electronic platforms for monitoring these inflammation biomarkers which manifest at ultralow concentration levels in physiopathological conditions. Specifically, two of the field's state-of-the-art technologies-organic electrochemical transistors (OECTs) and electrolyte gated organic field effect transistors (EGOFETs)-and their use in sensing cytokines and other proteins associated with inflammation are a particular focus. The overview will include an introduction to current clinical and "gold standard" quantification techniques and their limitations in terms of cost, time, and required infrastructure. A critical review of recent progress with OECT- and EGOFET-based protein biosensors is presented, alongside a discussion onthe future of these technologies in the years and decades ahead. This is especially timely as the world grapples with limited healthcare diagnostics during the Coronavirus disease (COVID-19)pandemic where one of the worst-case scenarios for patients is the "cytokine storm." Clearly, low-cost point-of-care technologies provided by OECTs and EGOFETs can ease the global burden on healthcare systems and support professionals by providing unprecedented wealth of data that can help to monitor disease progression in real time.

Nanomaterial-Based Drug Targeted Therapy for Cardiovascular Diseases: Ischemic Heart Failure and Atherosclerosis

Cardiovascular diseases (CVDs) represent the most important epidemic of our century, with more than 37 million patients globally. Furthermore, CVDs are associated with high morbidity and mortality, and also increased hospitalization rates and poor quality of life. Out of the plethora of conditions that can lead to CVDs, atherosclerosis and ischemic heart disease are responsible for more than 2/3 of the cases that end in severe heart failure and finally death. Current therapy strategies for CVDs focus mostly on symptomatic benefits and have a moderate impact on the underlying physiopathological mechanisms. Modern therapies try to approach different physiopathological pathways such as reduction of inflammation, macrophage regulation, inhibition of apoptosis, stem-cell differentiation and cellular regeneration. Recent technological advances make possible the development of several nanoparticles used not only for the diagnosis of cardiovascular diseases, but also for targeted drug delivery. Due to their high specificity, nanocarriers can deliver molecules with poor pharmacokinetics and dynamics such as: peptides, proteins, polynucleotides, genes and even stem cells. In this review we focused on the applications of nanoparticles in the diagnosis and treatment of ischemic heart failure and atherosclerosis.

Macrophage NFATc3 prevents foam cell formation and atherosclerosis: evidence and mechanisms

AIMS

Our previous study demonstrated that Ca2+ influx through the Orai1 store-operated Ca2+ channel in macrophages contributes to foam cell formation and atherosclerosis via the calcineurin-ASK1 pathway, not the classical calcineurin-nuclear factor of activated T-cell (NFAT) pathway. Moreover, up-regulation of NFATc3 in macrophages inhibits foam cell formation, suggesting that macrophage NFATc3 is a negative regulator of atherogenesis. Hence, this study investigated the precise role of macrophage NFATc3 in atherogenesis.

METHODS AND RESULTS

Macrophage-specific NFATc3 knockout mice were generated to determine the effect of NFATc3 on atherosclerosis in a mouse model of adeno-associated virus-mutant PCSK9-induced atherosclerosis. NFATc3 expression was decreased in macrophages within human and mouse atherosclerotic lesions. Moreover, NFATc3 levels in peripheral blood mononuclear cells from atherosclerotic patients were negatively associated with plaque instability. Furthermore, macrophage-specific ablation of NFATc3 in mice led to the atherosclerotic plaque formation, whereas macrophage-specific NFATc3 transgenic mice exhibited the opposite phenotype. NFATc3 deficiency in macrophages promoted foam cell formation by potentiating SR-A- and CD36-meditated lipid uptake. NFATc3 directly targeted and transcriptionally up-regulated miR-204 levels. Mature miR-204-5p suppressed SR-A expression via canonical regulation. Unexpectedly, miR-204-3p localized in the nucleus and inhibited CD36 transcription. Restoration of miR-204 abolished the proatherogenic phenotype observed in the macrophage-specific NFATc3 knockout mice, and blockade of miR-204 function reversed the beneficial effects of NFATc3 in macrophages.

CONCLUSION

Macrophage NFATc3 up-regulates miR-204 to reduce SR-A and CD36 levels, thereby preventing foam cell formation and atherosclerosis, indicating that the NFATc3/miR-204 axis may be a potential therapeutic target against atherosclerosis.

Helianthus Annuus L. Alleviates High-Fat Diet Induced Atherosclerosis by Regulating Intestinal Microbiota, Inhibiting Inflammation and Restraining Oxidative Stress

Helianthus Annuus L. (HAL) is composed of flavonoids and polysaccharides. Flavonoids have demonstrated beneficial effects on atherosclerosis (AS). The objective of this study was to investigate the anti-atherosclerosis effect and the related mechanism of HAL. In this study, the AS model induced by high-fat diet (HFD) mice that lacked apolipoprotein E (Apoe[Formula: see text] received feed containing 5% HAL for 24 weeks. After administration, the analysis of plaque on aorta was conducted, and the possible mechanisms were further explored. With HAL treatment, the size of atherosclerotic lesions in HFD-induced AS model mice was reduced. HAL ameliorated dyslipidemia and decreased the combined ratio. HAL up-regulated concentrations of superoxide dismutase (SOD), nitric oxide (NO) and glutathione peroxidase (GSH-Px) and down-regulated concentrations of malondialdehyde (MDA) in the aorta. In addition, 16S rRNA analysis showed that HAL also reduced diversity of the intestinal microbiota, decreased the Firmicutes-to-Bacteroidetes ratio, and increased the relative abundance of probiotics such as Akkermansia muciniphila and Lactobacillus. In the end, HAL decreased the permeability of intestine by increasing the levels of occludin and tight junction protein 1 (ZO-1) in the colon, consequently decreasing concentration of interleukin (IL)-6, IL-1[Formula: see text] and tumor necrosis factor-alpha (TNF-[Formula: see text] in serum and mRNA expressions in the aorta. Data showed that HAL alleviates AS by restraining oxidative stress, regulating intestinal microbiota, decreasing intestinal permeability and inhibiting inflammation. Our findings provided novel insights into the role and mechanism of anti-atherogenic potential of HAL.

Endometriosis Is Associated with an Increased Risk of Coronary Artery Disease in Asian Women

Endometriosis is a common systemic chronic inflammatory disease. Inflammation is the key mechanism responsible for the development of endothelial dysfunction and atherosclerosis. We aimed to investigate the risk of coronary artery disease (CAD) among Asian women with endometriosis. This retrospective population-based cohort study included patients with endometriosis diagnosed from 2000 to 2012 and registered in the Longitudinal Health Insurance Database, Taiwan. The comparison cohort (those without endometriosis) were selected (1:4) by matching the age frequency and the index year. We followed up the patients until the diagnosis of CAD (ICD-9-CM codes: 410-414, A270, and A279), withdrawal from the National Health Insurance system, death, or the end of the study. We used a multivariable-adjusted Cox proportional hazard model for evaluating the risk of CAD. We included 19,454 patients with endometriosis and 77,816 women as a comparison group. The mean age of the women at the diagnosis of endometriosis was 37.4 years. A total of 3245 women developed CAD in both groups during a median follow-up of 7 years. The incidence of CAD was higher in women with endometriosis than in those without (5.96 vs. 4.38 per 10,000 person-years; adjusted hazard ratio [95% confidence interval], 1.34 [1.22-1.47]). In conclusion, Asian women with endometriosis had a significantly higher risk of CAD. Further large-scale studies are needed to elucidate the cause-effect relationship between endometriosis and CAD.

LCC-09, a Novel Salicylanilide Derivative, Exerts Anti-Inflammatory Effect in Vascular Endothelial Cells

OBJECTIVE

Endothelial cell (EC) activation facilitates leukocyte adhesion to vascular walls, which is implicated in a variety of cardiovascular diseases and is a target for prevention and treatment. Despite the development of anti-inflammatory medications, cost-effective therapies with significant anti-inflammatory effects and lower organ toxicity remain elusive. The goal of this study is to identify novel synthetic compounds that inhibit EC inflammatory response with minimal organ toxicity.

METHODS AND RESULTS

In this study, we discovered LCC-09, a salicylanilide derivative consisting of the functional fragment of magnolol, 2,4-difluorophenyl, and paeonol moiety of salicylate, as a novel anti-inflammatory compound in cultured ECs and zebrafish model. LCC-09 was shown to inhibit pro-inflammatory cytokine tumor necrosis factor-α (TNFα)-induced expression of adhesion molecules and inflammatory cytokines, leading to reduced leukocyte adhesion to ECs. Mechanistically, LCC-09 inhibits the phosphorylation of signal transducer and activator of transcription 1 (STAT1), TNFα-induced degradation of NF-κ-B Inhibitor-α (IκBα) and phosphorylation of NFκB p65, resulting in reduced NFκB transactivation activity and binding to E-selectin promoter. Additionally, LCC-09 attenuated TNFα-induced generation of reactive oxygen species in ECs. Molecular docking models suggest the binding of LCC-09 to NFκB essential modulator (NEMO) and Janus tyrosine kinase (JAK) may lead to dual inhibition of NFκB and STAT1. Furthermore, the anti-inflammatory effect of LCC-09 was validated in the lipopolysaccharides (LPS)-induced inflammation model in zebrafish. Our results demonstrated that LCC-09 significantly reduced the LPS-induced leukocyte recruitment and mortality of zebrafish embryos. Finally, LCC-09 was administered to cultured ECs and zebrafish embryos and showed minimal toxicities.

CONCLUSION

Our results support that LCC-09 inhibits EC inflammatory response but does not elicit significant toxicity.

Targeting interleukin-β by plant-derived natural products: Implications for the treatment of atherosclerotic cardiovascular disease

Inflammation is the main contributing factor to atheroma formation in atherosclerosis. Interleukin-1 beta (IL-1β) is an inflammatory mediator found in endothelial cells and resident leukocytes. Canakinumab is a selective monoclonal antibody against IL-1β which attenuates inflammation and concurrently precipitates fatal infections and sepsis. Natural products derived from medicinal plants, herbal remedy and functional foods are widely used nowadays. Experimental and clinical trial evidence supports that some natural products such as curcumin, resveratrol, and quercetin have potential effects on IL-1β suppression. In this review, we tried to document findings that used medicinal plants and plant-based natural products for treating atherosclerosis and its related diseases through the suppression of IL-1β.

Asymmetric Dimethylarginine: a Key Player in the Pathophysiology of Endothelial Dysfunction, Vascular Inflammation and Atherosclerosis in Rheumatoid Arthritis?

Patients with rheumatoid arthritis (RA), a chronic and disabling autoimmune condition that is characterized by articular and extra-articular manifestations and a pro-inflammatory and pro-oxidant state, suffer from premature atherosclerosis and excessive cardiovascular disease burden. A key step in the pathogenesis of atherosclerosis is impaired synthesis of the endogenous messenger nitric oxide (NO) by endothelial cells which, in turn, alters local homeostatic mechanisms and favors vascular damage and plaque deposition. While the exact mechanisms of endothelial dysfunction in RA remain to be established, there is good evidence that RA patients have relatively high circulating concentrations of the methylated arginine asymmetric dimethylarginine (ADMA), a potent endogenous inhibitor of endothelial NO synthase (eNOS). This review discusses the biological and pathophysiological role of ADMA, the interplay between ADMA, inflammation and oxidative stress, and the available evidence on the adverse impact of ADMA on endothelial function and atherosclerosis and potential ADMA-lowering therapies in RA patients.

Circ_0093887 upregulates CCND2 and SUCNR1 to inhibit the ox-LDL-induced endothelial dysfunction in atherosclerosis by functioning as a miR-876-3p sponge

Circular RNAs (circRNAs) are widely expressed in mammals and act as regulatory targets in the atherogenesis. The objective of this study was to research the biological role and molecular mechanism of circ_0093887 in oxidized low-density lipoprotein (ox-LDL)-induced atherosclerosis (AS) of human aortic endothelial cells (HAECs). Cell viability detection was performed by CCK-8 assay. Inflammatory molecules were examined using ELISA. Flow cytometry was used to measure cell-cycle progression and cell apoptotic rate. Caspase 3 activity was determined using caspase 3 activity assay. The expression levels of circ_0093887, miR-876-3p, CCND2 and SUCNR1 were assayed by quantitative real-time polymerase chain reaction (qRT-PCR). Dual-luciferase reporter, RNA immunoprecipitation (RIP) and RNA pull-down assays were used for the target analysis. EdU assay, wound healing assay/transwell assay and tube formation assay were, respectively, used to assess the effects of circ_0093887/miR-876-3p axis on cell proliferation, migration and tube formation. Oxidized low-density lipoprotein inhibited cell viability and cell-cycle progression but induced the inflammatory response and cell apoptosis. Circ_0093887 was downregulated and miR-876-3p was upregulated in AS patients and ox-LDL-treated HAECs. Functionally, the overexpression of circ_0093887 abrogated the cell injury of HAEC exposed to ox-LDL. For the functional mechanism, we found that circ_0093887 was a sponge for miR-876-3p and miR-876 targeted CCND2 or SUCNR1. The reverted experiment indicated that the function of circ_0093887 was achieved by sponging miR-876-3p. Meanwhile, miR-876-3p inhibitor relieved the inhibitory regulation of circ_0093887 knockdown in cell proliferation, migration and tube formation. Downregulation of miR-876-3p also alleviated the ox-LDL-induced cell injury by upregulating the expression of CCND2 or SUCNR1. Furthermore, circ_0093887 was validated to regulate the levels of CCND2 and SUCNR1 via the sponge effect on miR-876-3p. The protective effects of circ_0093887 on HAECs from ox-LDL were also ​alleviated by repressing the CCND2 and SUCNR1 levels. These findings suggested that circ_0093887 protected HAEC against the ox-LDL-induced inflammatory and apoptotic damages by targeting the miR-876-3p/CCND2 or miR-876/SUCNRA axis. Circ_0093887 could act as a potential therapeutic biomarker for AS patients.

The association of air pollutants exposure with subclinical inflammation and carotid atherosclerosis

BACKGROUND

Air pollution is a well-described environmental factor with evidence suggesting a firm association with cardiovascular diseases. The purpose of this study was to determine the association of exposure to gaseous air pollutants on atherosclerosis burden.

METHODS

1955 inhabitants of the Corinthia region, aged 40 years or older, underwent clinical and biochemical assessment as well as carotid ultrasonography to evaluate carotid intima-media thickness (cIMT) and plaque burden. Analyzers recording time series concentration of CO, NO₂, and SO₂ were located at 4 different open sites (Regions 1, 2, 3 and 4) based on their proximity to industries, highways or shipyards.

RESULTS

A higher concentration of CO, NO2, and SO2 was observed in Region 4 compared to the other regions. Mean cIMT (Region 1: 0.93 ± 0.24 mm; Region 2: 0.96 ± 0.40 mm; Region 3: 0.94 ± 0.39 mm; Region 4: 1.14 ± 0.55 mm, p < 0.001), maximum cIMT (p < 0.001) as well as carotid plaque burden (Region 1: 13.3%; Region 2: 18.8%; Region 3: 22.4%; Region 4: 38.6%, p < 0.001) were significantly higher in individuals of Region 4. Inhabitants of Region 4 had also higher levels of C reactive protein (Region 1: 4.56 ± 4.85 mg/l; Region 2: 3.49 ± 4.46 mg/l; Region 3: 4.03 ± 3.32 mg/l, Region 4: 5.16 ± 8.26 mg/l, p < 0.001). Propensity score analysis revealed higher inter-area differences in mean cIMT of individuals with coronary artery disease (CAD) (high vs low air pollution area: 1.56 ± 0.80 mm; vs. 1.18 ± 0.54 mm, p < 0.001) while there was no difference in cIMT of the matched population without CAD (p = 0.52).

CONCLUSIONS

An increased carotid atherosclerotic and inflammatory burden is observed in inhabitants of areas with the highest concentration of air pollutants.

What Links an Increased Cardiovascular Risk and Inflammatory Bowel Disease? A Narrative Review

Several studies have shown increased rates of cardiovascular disease (CVD) in patients suffering from inflammatory bowel disease (IBD), particularly in cases of early atherosclerosis and myocardial infarction. IBD most frequently begins at an early age, patients usually present normal weight and remain under constant care of a physician, as well as of a nutritionist. Therefore, the classical risk factors of CVD are not reflected in the higher prevalence of CVD in the IBD population. Still, both groups are characterised by chronic inflammation and display similar physiopathological mechanisms. In the course of IBD, increased concentrations of pro-inflammatory cytokines, such as C-reactive protein (CRP) and homocysteine, may lead to endothelial dysfunctions and the development of CVD. Furthermore, gut microbiota dysbiosis in patients with IBD also constitutes a risk factor for an increased susceptibility to cardiovascular disease and atherosclerosis. Additionally, diet is an essential factor affecting both positively and negatively the course of the aforementioned diseases, whereas several dietary patterns may also influence the association between IBD and CVD. Thus, it is essential to investigate the factors responsible for the increased cardiovascular (CV) risk in this group of patients. Our paper attempts to review the role of potential inflammatory and nutritional factors, as well as intestinal dysbiosis and pharmacotherapy, in the increased risk of CVD in IBD patients.

Exploring the regulatory roles of circular RNAs in the pathogenesis of atherosclerosis

Circular RNAs (circRNAs) are a class of noncoding RNAs with a covalently closed loop structure. Recent evidence has shown that circRNAs can regulate gene transcription, alternative splicing, microRNA (miRNA) "molecular sponges", RNA-binding proteins and protein translation. Atherosclerosis is one of the leading causes of death worldwide, and more studies have indicated that circRNAs are related to atherosclerosis pathogenesis, including vascular endothelial cells, vascular smooth muscle cells, inflammation and lipid metabolism. In this review, we systematically summarize the biogenesis, characteristics and functions of circRNAs with a focus on their roles in the pathogenesis of atherosclerosis.

Molecular Dysfunctions of Mitochondria-Associated Endoplasmic Reticulum Contacts in Atherosclerosis

Atherosclerosis is a chronic lipid-driven inflammatory disease that results in the formation of lipid-rich and immune cell-rich plaques in the arterial wall, which has high morbidity and mortality in the world. The mechanism of atherosclerosis is still unclear now. Potential hypotheses involved in atherosclerosis are chronic inflammation theory, lipid percolation theory, mononuclear-macrophage theory, endothelial cell (EC) injury theory, and smooth muscle cell (SMC) mutation theory. Changes of phospholipids, glucose, critical proteins, etc. on mitochondria-associated endoplasmic reticulum membrane (MAM) can cause the progress of atherosclerosis. This review describes the structural and functional interaction between mitochondria and endoplasmic reticulum (ER) and explains the role of critical molecules in the structure of MAM during atherosclerosis.

Inflammatory Mechanisms in COVID-19 and Atherosclerosis: Current Pharmaceutical Perspectives

Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been associated with excess mortality worldwide. The cardiovascular system is the second most common target of SARS-CoV-2, which leads to severe complications, including acute myocardial injury, myocarditis, arrhythmias, and venous thromboembolism, as well as other major thrombotic events because of direct endothelial injury and an excessive systemic inflammatory response. This review focuses on the similarities and the differences of inflammatory pathways involved in COVID-19 and atherosclerosis. Anti-inflammatory agents and immunomodulators have recently been assessed, which may constitute rational treatments for the reduction of cardiovascular events in both COVID-19 and atherosclerotic heart disease.

Uremic Toxins and Their Relation with Oxidative Stress Induced in Patients with CKD

The presence of toxins is believed to be a major factor in the development of uremia in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD). Uremic toxins have been divided into 3 groups: small substances dissolved in water, medium molecules: peptides and low molecular weight proteins, and protein-bound toxins. One of the earliest known toxins is urea, the concentration of which was considered negligible in CKD patients. However, subsequent studies have shown that it can lead to increased production of reactive oxygen species (ROS), and induce insulin resistance in vitro and in vivo, as well as cause carbamylation of proteins, peptides, and amino acids. Other uremic toxins and their participation in the damage caused by oxidative stress to biological material are also presented. Macromolecules and molecules modified as a result of carbamylation, oxidative stress, and their adducts with uremic toxins, may lead to cardiovascular diseases, and increased risk of mortality in patients with CKD.

Serum levels of IL-32 in patients with coronary artery disease and its relationship with the serum levels of IL-6 and TNF-α

The coronary artery disease (CAD) is a chronic inflammatory disease caused by atherosclerosis, in which arteries become clogged due to plaque formation, fat accumulation, and various sorts of immune cells. IL-32 is a proinflammatory cytokine, which enhances inflammation through inducing the secretion of different inflammatory cytokines. The main objective of the current study was to assess the serum levels of IL-32 in subjects with obstructive CAD and its relationship with the serum levels of IL-6 and TNF-α. This study was performed on 42 subjects with obstructive CAD and 42 subjects with non-obstructive CAD. The serum levels of TNF-α, IL-6, and IL-32 were measured using the enzyme-linked immunosorbent assay (ELISA). The serum levels of TNF-α, IL-6, and IL-32 were 3.2, 3.48, and 2.7 times higher in obstructive CAD compared to non-obstructive CAD, respectively. Moreover, the serum levels of TNF-α and IL-32 in obstructive CAD with cardiac arterial stenosis in one major vessel were significantly higher than the levels in obstructive CAD with cardiac arterial stenosis in more than one major vessel. ROC curve analysis revealed that the serum levels of TNF-α, IL-6, and IL-32 were good predictors of obstructive CAD. Moreover, multiple logistic regression analyses suggested that the serum levels of TNF-α, IL-6, IL-32, LDL, and ox-LDL were independently related to the presence of obstructive CAD, while serum levels of HDL were not. TNF-α, IL-32, and IL-6 showed an increase in obstructive CAD, and the serum levels of these cytokines showed a satisfactory ability for predicting obstructive CAD.

Inclisiran-Silencing the Cholesterol, Speaking up the Prognosis

The reduction of circulating low-density lipoprotein-cholesterol (LDL-C) is a primary target in cardiovascular risk reduction due to its well-established benefits in terms of decreased mortality. Despite the use of statin therapy, 10%-20% of high- and very-high-risk patients do not reach their LDL-C targets. There is an urgent need for improved strategies to manage dyslipidemia, especially among patients with homozygous familial hypercholesterolemia, but also in patients with established cardiovascular disease who fail to achieve LDL goals despite combined statin, ezetimibe, and PCSK9 inhibitor (PCSK9i) therapy. Inclisiran is a disruptive, first-in-class small interfering RNA (siRNA)-based therapeutic developed for the treatment of hypercholesterolemia that inhibits proprotein convertase subtilisin-kexin type 9 (PCSK9) synthesis, thereby upregulating the number of LDL receptors on the hepatocytes, thus lowering the plasma LDL-C concentration. Inclisiran decreases the LDL-C levels by over 50% with one dose every 6 months, making it a simple and well-tolerated treatment strategy. In this review, we summarize the general information regarding (i) the role of LDL-C in atherosclerotic cardiovascular disease, (ii) data regarding the role of PCSK9 in cholesterol metabolism, (iii) pleiotropic effects of PCSK9, and (iv) the effects of PCSK9 silencing. In addition, we focus on inclisiran, in terms of its (i) mechanism of action, (ii) biological efficacy and safety, (iii) results from the ORION trials, (iv) benefits of its combination with statins, and (v) its potential future role in atherosclerotic cardiovascular disease.

Imaging and Targeting Coronary Artery Inflammation

Significance: Coronary artery disease (CAD) continues to be a leading cause of morbidity and mortality across the world despite significant progress in the prevention, diagnosis, and treatment of atherosclerotic disease. Recent Advances: The focus of the cardiovascular community has shifted toward seeking a better understanding of the inflammatory mechanisms driving residual CAD risk that is not modulated by current therapies. Significant progress has been achieved in revealing both proinflammatory and anti-inflammatory mechanisms, and how shift of the balance in favor of the former can drive the development of disease. Critical Issues: Advances in the noninvasive detection of coronary artery inflammation have been forthcoming. These advances include multiple imaging modalities, with novel applications of computed tomography both with and without positron emission tomography, and experimental ultrasound techniques. These advances will enable better selection of patients for anti-inflammatory treatments and assessment of treatment response. The rapid advancement in pharmaceutical design has enabled the production of specific antibodies against inflammatory pathways of atherosclerosis, with modest success to date. The pursuit of demonstrating the efficacy and safety of novel anti-inflammatory and/or proinflammatory resolution therapies for atherosclerotic CAD has become a major focus. Future Directions: This review seeks to provide an update of the latest evidence of all three of these highly related but disparate areas of inquiry: Our current understanding of the key mechanisms by which inflammation contributes to coronary artery atherosclerosis, the evidence for noninvasive assessment of coronary artery inflammation, and finally, the evidence for targeted therapies to treat coronary inflammation for the reduction of CAD risk. Antioxid. Redox Signal. 34, 1217-1243.

Targeting inflammation-associated AMPK//Mfn-2/MAPKs signaling pathways by baicalein exerts anti-atherosclerotic action

Inflammatory responses in macrophages, endothelial cells, and vascular smooth muscle cells play crucial roles in the development of atherosclerosis. Baicalein, a flavonoid phytochemical, possesses anti-inflammatory properties, but the underlying mechanisms of its action are not fully understood. The aim of this study was to explore whether baicalein inhibited inflammatory activities in RAW264.7, HUVEC, and MOVAS cells and to analyze its underlying mechanisms. Our results showed that baicalein treatment effectively reduced the levels of IL-6, TNF-α, PAI-1, and MMP-9 released by these cells upon stimulation with Ang II or ox-LDL. We discovered that the molecular mechanisms underlying baicalein suppression of the generation of proinflammatory cytokines were associated with the inhibition of MAPK/NF-κB pathway activity. Moreover, Ang II and ox-LDL intervention decreased the content of Mfn-2 in the three types of cells, but incubation of baicalein alleviated the Ang II/ox-LDL-induced reduction of Mfn-2 levels. Adv-Mfn2 treatment not only increased the expression of Mfn-2 but also reduced the levels of phosphorylated ERK1/2, p38, JNK, and NF-κB, followed by a decrease in the concentrations of IL-6, TNF-α, PAI-1, and MMP-9 in the supernatant. Furthermore, our findings indicated that baicalein treatment markedly suppressed the decrease in AMPK activity induced with Ang II and ox-LDL, and incubation with Compound C reversed the effects of baicalein on AMPK activation and Mfn-2 expression. In conclusion, our data suggest that baicalein shows anti-inflammatory properties, probably by activating the AMPK/Mfn-2 axis, accompanied by inhibition of downstream MAPKs/NF-κB signaling transduction.

Browning of White Adipose Tissue as a Therapeutic Tool in the Fight against Atherosclerosis

Despite continuous medical advances, atherosclerosis remains the prime cause of mortality worldwide. Emerging findings on brown and beige adipocytes highlighted that these fat cells share the specific ability of non-shivering thermogenesis due to the expression of uncoupling protein 1. Brown fat is established during embryogenesis, and beige cells emerge from white adipose tissue exposed to specific stimuli like cold exposure into a process called browning. The consecutive energy expenditure of both thermogenic adipose tissues has shown therapeutic potential in metabolic disorders like obesity and diabetes. The latest data suggest promising effects on atherosclerosis development as well. Upon cold exposure, mice and humans have a physiological increase in brown adipose tissue activation and browning of white adipocytes is promoted. The use of drugs like β3-adrenergic agonists in murine models induces similar effects. With respect to atheroprotection, thermogenic adipose tissue activation has beneficial outcomes in mice by decreasing plasma triglycerides, total cholesterol and low-density lipoproteins, by increasing high-density lipoproteins, and by inducing secretion of atheroprotective adipokines. Atheroprotective effects involve an unaffected hepatic clearance. Latest clinical data tend to find thinner atherosclerotic lesions in patients with higher brown adipose tissue activity. Strategies for preserving healthy arteries are a major concern for public health.

Effect of Biologics on Cardiovascular Inflammation: Mechanistic Insights and Risk Reduction

It is increasingly recognized that atherosclerosis and consequently cardiovascular disease (CVD) are closely linked with inflammatory processes. The latter is in the center of the pathogenic mechanism underlying autoimmune rheumatic diseases (ARD). It follows then, that optimal control of inflammation in ARDs may lead to a decrease of the accompanied CVD risk. Major trials (eg, CANTOS, CIRT), aimed at examining the possible benefits of immunomodulatory treatments in CVD, demonstrated conflicting results. On the other hand, substantial evidence is accumulating about the possible beneficial effects of biologic disease modifying antirheumatic drugs (bDMARDs) in patients with ARDs, particularly those with rheumatoid arthritis (RA). It seems that bDMARDs (some more than others) alter the lipid profile in RA patients but do not adversely affect, in most cases, the TC/HDL ratio. Favorable effects are noted for arterial stiffness and endothelial function. This is reflected in the lower risk for CVD events, seen in observational studies of RA patients treated with bDMARDs. It should be stressed that more data exist for the TNF-inhibitors than for other bDMARDs, such as tocilizumab, abatacept and rituximab. As regards the spondyloarthropathies (SpA), data are less robust. For TNF-inhibitors, effects appear to be on par with those seen in RA but no conclusions can be drawn for newer biologic drugs used in SpA (eg, IL-17 blockers). Finally, there is accumulating evidence for a beneficial effect of immunosuppressive treatment in cardiac inflammation and function in several ARDs. Introduction of newer therapeutic options in clinical practice seem to have a positive impact on CVD in the setting of ARD. This is probably due to better control of inflammation, but direct improvement in vascular pathology is also a valid hypothesis. Most data are derived from observational studies and, therefore, randomized controlled trials are needed to assess the possible favorable effect of bDMARDs on CVD outcomes.

Inflamm-ageing: the role of inflammation in age-dependent cardiovascular disease

The ongoing worldwide increase in life expectancy portends a rising prevalence of age-related cardiovascular (CV) diseases in the coming decades that demands a deeper understanding of their molecular mechanisms. Inflammation has recently emerged as an important contributor for CV disease development. Indeed, a state of chronic sterile low-grade inflammation characterizes older organisms (also known as inflamm-ageing) and participates pivotally in the development of frailty, disability, and most chronic degenerative diseases including age-related CV and cerebrovascular afflictions. Due to chronic activation of inflammasomes and to reduced endogenous anti-inflammatory mechanisms, inflamm-ageing contributes to the activation of leucocytes, endothelial, and vascular smooth muscle cells, thus accelerating vascular ageing and atherosclerosis. Furthermore, inflamm-ageing promotes the development of catastrophic athero-thrombotic complications by enhancing platelet reactivity and predisposing to plaque rupture and erosion. Thus, inflamm-ageing and its contributors or molecular mediators might furnish targets for novel therapeutic strategies that could promote healthy ageing and conserve resources for health care systems worldwide. Here, we discuss recent findings in the pathophysiology of inflamm-ageing, the impact of these processes on the development of age-related CV diseases, results from clinical trials targeting its components and the potential implementation of these advances into daily clinical practice.

Shear stress and ROS-responsive biomimetic micelles for atherosclerosis via ROS consumption

Reactive oxygen species (ROS) are well-known important initiating factors required for atherosclerosis formation, which leads to endothelial dysfunction and plaque formation. Most of the existing antithrombotic therapies use ROS-responsive drug delivery systems, which have a certain therapeutic effect but cannot eliminate excess ROS. Therefore, the atherosclerosis cannot be treated from the source. Moreover, nanoparticles are easily cleared by the immune system during blood circulation, which is not conducive to long-term circulation. In this study, we developed an intelligent response system that could simultaneously respond to ROS and the shear stress microenvironment of atherosclerotic plaques. This system was formed by red blood cells (RBCs) and simvastatin-loaded micelles (SV MC). The micelles consisted of poly(glycidyl methacrylate)-polypropylene sulfide (PGED-PPS). The hydrophobic PPS could react with excess ROS to become hydrophilic, which forced the micelle rupture, resulting in drug release. Most importantly, PPS could also significantly deplete the ROS level, realizing the synergistic treatment of atherosclerosis with drugs and materials. The positively charged SV MC and negatively charged RBCs were self-assembled through electrostatic adsorption to obtain SV MC@RBCs. The SV MC@RBCs could respond to the high shear stress at the atherosclerotic plaque, and the shear stress induced SV MC desorption from the RBC surface. Using biomimetic methods to evade the SV MC@RBCs elimination by the immune system and to reduce the ROS plays a vital role in improving atherosclerosis treatment. The results of in vitro and in vivo experiments showed that SV MC@RBCs could effectively treat atherosclerosis. Moreover, not only does the SV MC@RBCs system avoid the risk of bleeding, but it also has excellent in vivo safety. The study results indicate that the SV MC@RBCs system is a promising therapeutic nanomedicine for treating ROS-related diseases.

Macrophage K63-Linked Ubiquitination of YAP Promotes Its Nuclear Localization and Exacerbates Atherosclerosis

The Hippo/Yes-associated protein (YAP) pathway has pivotal roles in innate immune responses against pathogens in macrophages. However, the role of YAP in macrophages during atherosclerosis and its mechanism of YAP activation remain unknown. Here, we find that YAP overexpression in myeloid cells aggravates atherosclerotic lesion size and infiltration of macrophages, whereas YAP deficiency reduces atherosclerotic plaque. Tumor necrosis factor receptor-associated factor 6 (TRAF6), a downstream effector of interleukin-1β (IL-1β), triggers YAP ubiquitination at K252, which interrupts the interaction between YAP and angiomotin and results in enhanced YAP nuclear translocation. The recombinant IL-1 receptor antagonist anakinra reduces atherosclerotic lesion formation, which is abrogated by YAP overexpression. YAP level is increased in human and mouse atherosclerotic vessels, and plasma IL-1β level in patients with STEMI is correlated with YAP protein level in peripheral blood mononuclear cells. These findings elucidate a mechanism of YAP activation, which might be a therapeutic target for atherosclerosis.