Subendothelial lipoprotein retention as the initiating process in atherosclerosis: update and therapeutic implications

Reactive Carbonyl Species and Protein Lipoxidation in Atherogenesis

Atherosclerosis is a multifactorial disease of medium and large arteries, characterized by the presence of lipid-rich plaques lining the intima over time. It is the main cause of cardiovascular diseases and death worldwide. Redox imbalance and lipid peroxidation could play key roles in atherosclerosis by promoting a bundle of responses, including endothelial activation, inflammation, and foam cell formation. The oxidation of polyunsaturated fatty acids generates various lipid oxidation products such as reactive carbonyl species (RCS), including 4-hydroxy alkenals, malondialdehyde, and acrolein. RCS covalently bind to nucleophilic groups of nucleic acids, phospholipids, and proteins, modifying their structure and activity and leading to their progressive dysfunction. Protein lipoxidation is the non-enzymatic post-translational modification of proteins by RCS. Low-density lipoprotein (LDL) oxidation and apolipoprotein B (apoB) modification by RCS play a major role in foam cell formation. Moreover, oxidized LDLs are a source of RCS, which form adducts on a huge number of proteins, depending on oxidative stress intensity, the nature of targets, and the availability of detoxifying systems. Many systems are affected by lipoxidation, including extracellular matrix components, membranes, cytoplasmic and cytoskeletal proteins, transcription factors, and other components. The mechanisms involved in lipoxidation-induced vascular dysfunction are not fully elucidated. In this review, we focus on protein lipoxidation during atherogenesis.

Dietary fat quality, plasma atherogenic lipoproteins, and atherosclerotic cardiovascular disease: An overview of the rationale for dietary recommendations for fat intake

The scientific evidence supporting the current dietary recommendations for fat quality keeps accumulating; however, a paradoxical distrust has taken root among many researchers, clinicians, and in parts of the general public. One explanation for this distrust may relate to an incomplete overview of the totality of the evidence for the link between fat quality as a dietary exposure, and health outcomes such as atherosclerotic cardiovascular disease (ASCVD). Therefore, the main aim of the present narrative review was to provide a comprehensive overview of the rationale for dietary recommendations for fat intake, limiting our discussion to ASCVD as outcome. Herein, we provide a core framework - a causal model - that can help us understand the evidence that has accumulated to date, and that can help us understand new evidence that may become available in the future. The causal model for fat quality and ASCVD is comprised of three key research questions (RQs), each of which determine which scientific methods are most appropriate to use, and thereby which lines of evidence that should feed into the causal model. First, we discuss the link between low-density lipoprotein (LDL) particles and ASCVD (RQ1); we draw especially on evidence from genetic studies, randomized controlled trials (RCTs), epidemiology, and mechanistic studies. Second, we explain the link between dietary fat quality and LDL particles (RQ2); we draw especially on metabolic ward studies, controlled trials (randomized and non-randomized), and mechanistic studies. Third, we explain the link between dietary fat quality, LDL particles, and ASCVD (RQ3); we draw especially on RCTs in animals and humans, epidemiology, population-based changes, and experiments of nature. Additionally, the distrust over dietary recommendations for fat quality may partly relate to an unclear understanding of the scientific method, especially as applied in nutrition research, including the process of developing dietary guidelines. We therefore also aimed to clarify this process. We discuss how we assess causality in nutrition research, and how we progress from scientific evidence to providing dietary recommendations.

Cholesterol trafficking, lysosomal function, and atherosclerosis

Despite years of study and major research advances over the past 50 years, atherosclerotic diseases continue to rank as the leading global cause of death. Accumulation of cholesterol within the vascular wall remains the main problem and represents one of the early steps in the development of atherosclerotic lesions. There is a complex relationship between vesicular cholesterol transport and atherosclerosis, and abnormalities in cholesterol trafficking can contribute to the development and progression of the lesions. The dysregulation of vesicular cholesterol transport and lysosomal function fosters the buildup of cholesterol within various intracytoplasmic compartments, including lysosomes and lipid droplets. This, in turn, promotes the hallmark formation of foam cells, a defining feature of early atherosclerosis. Multiple cellular processes, encompassing endocytosis, exocytosis, intracellular trafficking, and autophagy, play crucial roles in influencing foam cell formation and atherosclerotic plaque stability. In this review, we highlight recent advances in the understanding of the intricate mechanisms of vesicular cholesterol transport and its relationship with atherosclerosis and discuss the importance of understanding these mechanisms in developing strategies to prevent or treat this prevalent cardiovascular disease.

Inhibition of circ_0000231 suppresses oxidized low density lipoprotein-induced apoptosis, autophagy and inflammation in human umbilical vein endothelial cells by regulating miR-590-5p/PDCD4 axis

BACKGROUND

Circular RNAs (circRNAs) are the emerging informative RNAs, involved in cardiovascular diseases including atherosclerosis (AS). Endothelial injury is the initial qualitative change of AS. Thus, the objective of this study was to confirm the dysregulation and mechanism of circ_0000231 in cell model of AS at early stage in human umbilical vein endothelial cells (HUVECs) induced by oxidized low-density lipoprotein (ox-LDL).

METHODS

The expression of circ_0000231, miR-590-5p and programmed cell death 4 (PDCD4) was detected using real-time quantitative PCR and western blot. Cell injury was measured with MTT, flow cytometry, caspase-3 activity assay and enzyme-linked immunosorbent assay (ELISA). The interaction among circ_0000231, miR-590-5p and PDCD4 was validated by dual-luciferase reporter assay, RNA immunoprecipitation (RIP) and pull-down assays.

RESULTS

Stress ox-LDL decreased cell viability, and increased apoptosis rate and caspase-3 activity in HUVECs in a dose- and time-dependent manner in concomitant with promotions of interleukin-6, interleukin-1β, tumor necrosis factor-α, LC3-II/I and Beclin-1 levels. Besides, circ_0000231 and PDCD4 expressions were upregulated, and miR-590-5p was downregulated in ox-LDL-stimulated HUVECs. Functionally, knockdown of circ_0000231 and overexpression of miR-590-5p could suppress ox-LDL-elicited above effects on apoptosis, autophagy and inflammatory response, accompanied with PDCD4 downregulation. Physically, miR-590-5p could directly interact with circ_0000231 and PDCD4.

CONCLUSION

Downregulation of circ_0000231 suppresses HUVECs from ox-LDL-induced injury partially through regulating miR-590-5p/PDCD4 axis via competing endogenous RNA mechanism, showing a novel potential target for the pathology and treatment of endothelial injury in AS.

Furin knockdown inhibited EndMT and abnormal proliferation and migration of endothelial cells

BACKGROUND

In the pathogenesis of atherosclerotic cardiovascular disorders, vascular endothelium is crucial. A critical step in the development of atherosclerosis is endothelial dysfunction. Furin may play a factor in vascular remodeling, inflammatory cell infiltration, regulation of plaque stability, and atherosclerosis by affecting the adhesion and migration of endothelial cells. It is yet unknown, though, how furin contributes to endothelial dysfunction.

METHODS

We stimulated endothelial cells with oxidized modified lipoprotein (ox-LDL). Endothelial-to-mesenchymal transition (EndMT) was found using immunofluorescence (IF) and western blot (WB). Furin expression level and Hippo/YAP signal activation were found using reverse transcription-quantitative PCR (RT-qPCR) and WB, respectively. To achieve the goal of furin knockdown, we transfected siRNA using the RNA transmate reagent. Following furin knockdown, cell proliferation, and migration were assessed by the CCK-8, scratch assay, and transwell gold assay, respectively. WB and IF both picked up on EndMT. WB and RT-qPCR, respectively, were used to find furin's expression level. We chose the important micrornas that can regulate furin and we then confirmed them using RT-qPCR.

RESULTS

EndMT was created by ox-LDL, evidenced by the up-regulation of mesenchymal cell markers and the down-regulation of endothelial cell markers. Furin expression levels in both protein and mRNA were increased, and the Hippo/YAP signaling pathway was turned on. Furin knockdown dramatically reduced the aberrant migration and proliferation of endothelial cells by ox-LDL stimulation. Furin knockdown can also suppress ox-LDL-induced EndMT, up-regulate indicators of endothelial cells, and down-regulate markers of mesenchymal cells. After ox-LDL stimulation and siRNA transfection, furin's expression level was up-regulated and down-regulated.

CONCLUSION

Our study demonstrated that furin knockdown could affect ox-LDL-induced abnormal endothelial cell proliferation, migration, and EndMT. This implies that furin plays an important role in endothelial dysfunction.

Signaling pathways regulating the extracellular digestion of lipoprotein aggregates by macrophages

The interaction between aggregated low-density lipoprotein (agLDL) and macrophages in arteries plays a major role in atherosclerosis. Macrophages digest agLDL and generate free cholesterol in an extracellular, acidic, hydrolytic compartment known as the lysosomal synapse. Macrophages form a tight seal around agLDL through actin polymerization and deliver lysosomal contents into this space in a process termed digestive exophagy. Our laboratory has identified TLR4 activation of MyD88/Syk as critical for digestive exophagy. Here we use pharmacological agents and siRNA knockdown to characterize signaling pathways downstream of Syk that are involved in digestive exophagy. Syk activates Bruton's tyrosine kinase (BTK) and phospholipase Cγ2 (PLCγ2). We show that PLCγ2 and to a lesser extent BTK regulate digestive exophagy. PLCγ2 cleaves PI(4,5)P2 into diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3). Soluble IP3 activates release of Ca2+ from the endoplasmic reticulum (ER). We demonstrate that Ca2+ release from the ER is upregulated by agLDL and plays a key role in digestive exophagy. Both DAG and Ca2+ activate protein kinase Cα (PKCα). We find that PKCα is an important regulator of digestive exophagy. These results expand our understanding of the mechanisms of digestive exophagy, which could be useful in developing therapeutic interventions to slow development of atherosclerosis.

Alternative lipid lowering strategies: State-of-the-art review of red yeast rice

Red yeast rice (RYR) is an entirely natural product that originates from the fermentation of white rice (Oryza sativa) with a yeast, mainly Monascus Purpureus, and has been part of traditional Chinese medicine and diet since ancient times. It has generated great interest in recent years in the context of cardiovascular (CV) prevention due to its ability to inhibit endogenous cholesterol production, helping to achieve and maintain optimal plasma lipid concentrations. This review aims to make an extensive 360-degree assessment and summary of the whole currently available scientific evidence about RYR, starting with its biochemical composition, passing through a historical reconstruction of all the studies that have evaluated its efficacy and safety in cholesterol-lowering action, with a focus on CV outcomes, and ultimately addressing its other relevant clinical effects. We also discuss its possible therapeutic role, alone or in combination with other nutraceuticals, in different clinical scenarios, taking into account the positions of major scientific documents on the issue, and describe the articulate legal controversies that have characterized the regulation of its use up to the present day. RYR preparations have been proven safe and effective in improving lipid profile, with a potential role in reducing cardiovascular risk. They can be considered as additional supportive agents in the armamentarium of lipid-modifying therapies.

Non-high-density lipoprotein cholesterol levels as a risk factor for short-term mortality in elderly Chinese: a large-scale, population-based cohort study

OBJECTIVES

To explore the association between non-high-density lipoprotein (non-HDL) and mortality risk, both short-term and long-term, in Chinese people.

DESIGN

A prospective cohort study.

SETTING

The National Basic Public Health Service (BPHS) in China.

PARTICIPANTS

Including 621 164 elderly individuals around Hunan Province who underwent healthcare management receiving check-ups in China BPHS from 2010 to 2020.

EXCLUSION CRITERIA

(1) missing information on gender; (2) missing records of lipid screening; (3) missing information on key covariates; and (4) missing records of comorbidities (cardiovascular disease, hypertension, diabetes, cancer.) PRIMARY AND SECONDARY OUTCOME MEASURES: The study's primary endpoint was all-cause and cause-specific mortality, sourced from Hunan's CDC(Center for Disease Control and Prevention)-operated National Mortality Surveillance System, tracking participants until 24 February 2021.

RESULTS

26 758 (4.3%) deaths were recorded, with a median follow-up of 0.83 years. Association between non-HDL and mortality was non-linear after multivariable adjustment, with the optimum concentration (OC) being 3.29 and 4.85 mmol/L. Compared with OC, the risk increased by 1.12-fold for non-HDL <3.29 mmol/L (HR: 1.12 (1.09 to 1.15)) and 1.08-fold for non-HDL ≥4.85 mmol/L (HR: 1.08 (1.02 to 1.13)) for all-cause mortality. Furthermore, there is also an increased risk of cardiovascular mortality (HR for non-HDL <3.29: 1.10 (1.06 to 1.32) and HR for non-HDL ≥4.85: 1.07 (1.01 to 1.14)). However, cancer mortality risk was significantly increased only for non-HDL <3.29 mmol/L (HR: 1.11 (1.04 to 1.18)). Non-optimum concentration of non-HDL had significant effects on both the long-term and the short-term risk of mortality, especially for risks of mortality for all-cause (log HR:0 .086 (0.038 to 0.134)), cardiovascular (log HR:0 .082 (0.021 to 0.144)), and cancer (log HR:0 .187 (0.058 to 0.315)) within 3 months. A two-sided value of p <0.05 was considered to be statistically significant.

CONCLUSIONS

Non-HDL was non-linearly associated with the risk of mortality, and non-optimal concentrations of non-HDL significantly increased short-term mortality in elderly Chinese, which needs more attention for cardiovascular disease prevention.

Postprandial Dysmetabolism and Its Medical Implications

An unbalanced diet increases the risk of developing a variety of chronic diseases and cancers, leading to higher morbidity and mortality rates worldwide. Low-grade systemic chronic inflammation mediated by the activation of the innate immune system is common to all these pathologies. Inflammation is a biological response of the body and a normal part of host defense to combat the effects of bacteria, viruses, toxins and macronutrients. However, when the innate immune system is constantly activated, it can promote the development of low-grade systemic chronic inflammation, which could play an important role in the development of chronic diseases and cancer. Since most chronic inflammatory diseases are associated with diet, a balanced healthy diet high in anti-inflammatory food components could prevent chronic diseases and cancer. The cells of the body's immune system produce chemokines and cytokines which can have pro-inflammatory and tumor-promoting as well as anti-inflammatory and tumor-fighting functions. A challenge in the future will be to assess whether polymorphisms in immune-related genes may play a role in promoting pro-inflammatory activity. Thanks to this duality, future research on immune regulation could focus on how innate immune cells can be modified to convert a pro-inflammatory and tumor-friendly microenvironment into an anti-inflammatory and anti-tumor one. This review describes inflammatory responses mediated by the innate immune system in various diseases such as hyperglycemia and/or hyperlipemia, obesity, type II diabetes, cardiovascular disease and cancer.

Nanomedicine for Diagnosis and Treatment of Atherosclerosis

With the changing disease spectrum, atherosclerosis has become increasingly prevalent worldwide and the associated diseases have emerged as the leading cause of death. Due to their fascinating physical, chemical, and biological characteristics, nanomaterials are regarded as a promising tool to tackle enormous challenges in medicine. The emerging discipline of nanomedicine has filled a huge application gap in the atherosclerotic field, ushering a new generation of diagnosis and treatment strategies. Herein, based on the essential pathogenic contributors of atherogenesis, as well as the distinct composition/structural characteristics, synthesis strategies, and surface design of nanoplatforms, the three major application branches (nanodiagnosis, nanotherapy, and nanotheranostic) of nanomedicine in atherosclerosis are elaborated. Then, state-of-art studies containing a sequence of representative and significant achievements are summarized in detail with an emphasis on the intrinsic interaction/relationship between nanomedicines and atherosclerosis. Particularly, attention is paid to the biosafety of nanomedicines, which aims to pave the way for future clinical translation of this burgeoning field. Finally, this comprehensive review is concluded by proposing unresolved key scientific issues and sharing the vision and expectation for the future, fully elucidating the closed loop from atherogenesis to the application paradigm of nanomedicines for advancing the early achievement of clinical applications.

Comparison between multiple logistic regression and machine learning methods in prediction of abnormal thallium scans in type 2 diabetes

BACKGROUND

The prevalence of type 2 diabetes (T2D) has been increasing dramatically in recent decades, and 47.5% of T2D patients will die of cardiovascular disease. Thallium-201 myocardial perfusion scan (MPS) is a precise and non-invasive method to detect coronary artery disease (CAD). Most previous studies used traditional logistic regression (LGR) to evaluate the risks for abnormal CAD. Rapidly developing machine learning (Mach-L) techniques could potentially outperform LGR in capturing non-linear relationships.

AIM

To aims were: (1) Compare the accuracy of Mach-L methods and LGR; and (2) Found the most important factors for abnormal TMPS.

METHODS

556 T2D were enrolled in the study (287 men and 269 women). Demographic and biochemistry data were used as independent variables and the sum of stressed score derived from MPS scan was the dependent variable. Subjects with a MPS score ≥ 9 were defined as abnormal. In addition to traditional LGR, classification and regression tree (CART), random forest, Naïve Bayes, and eXtreme gradient boosting were also applied. Sensitivity, specificity, accuracy and area under the receiver operation curve were used to evaluate the respective accuracy of LGR and Mach-L methods.

RESULTS

Except for CART, the other Mach-L methods outperformed LGR, with gender, body mass index, age, low-density lipoprotein cholesterol, glycated hemoglobin and smoking emerging as the most important factors to predict abnormal MPS.

CONCLUSION

Four Mach-L methods are found to outperform LGR in predicting abnormal TMPS in Chinese T2D, with the most important risk factors being gender, body mass index, age, low-density lipoprotein cholesterol, glycated hemoglobin and smoking.

G-Protein-Coupled Receptor 91-Dependent Signalling Does Not Influence Vascular Inflammation and Atherosclerosis in Hyperlipidaemic Mice

The TCA cycle intermediate metabolite 'succinate' has been proposed as an inflammatory mediator, influencing autoimmunity and allergic reactions, through ligation to its sensing receptor SUCNR1/GPR91. Whether GPR91-mediated signalling influences the chronic inflammatory process of atherosclerosis has never been investigated. The examination of publicly available datasets revealed that the SUCNR1 gene is expressed in human atherosclerotic plaques, especially in vascular smooth muscle cells. Using GPR91 knockout (Gpr91-/-) and wildtype (WT) littermates, made hyperlipidaemic with the overexpression of the gain-of-function mutated Pcsk9 and Western diet feeding, we showed that the full ablation of GPR91 did not accelerate atherosclerosis-lesions in the aortic arch 2.18 ± 0.48% vs. 1.64 ± 0.31%, and in the aortic roots 10.06 ± 0.91% vs. 10.67 ± 1.53% for Gpr91-/- and WT mice, respectively. In line with this, no differences between groups were observed for macrophage and T-cell infiltration in the plaque, as well as the polarization towards M1- or M2-like macrophages in the aorta, spleen and liver of Gpr91-/- and WT control mice. In conclusion, our study indicates that the global ablation of GPR91 signalling does not influence vascular inflammation or atherogenesis.

Lipoproteins, Cholesterol, and Atherosclerotic Cardiovascular Disease in East Asians and Europeans

One fifth of the world population live in East Asia comprising Japan, Korea, and China where ischemic heart disease, a major component of atherosclerotic cardiovascular disease (ASCVD), is the second most frequent cause of death. Each of low-density lipoproteins (LDL), remnant lipoproteins, and lipoprotein(a), summarized as non-high-density lipoproteins (non-HDL) or apolipoprotein B (apoB) containing lipoproteins, causes ASCVD. However, a significant proportion of the evidence on lipoproteins and lipoprotein cholesterol with risk of ASCVD came from White people mainly living in Europe and North America and not from people living in East Asia or of East Asian descent. With a unique biological, geohistorical, and social background in this world region, East Asians have distinctive characteristics that might have potential impact on the association of lipoproteins and lipoprotein cholesterol with risk of ASCVD. Considering the movement across national borders in the World, understanding of lipoprotein and lipoprotein cholesterol evidence on ASCVD in East Asia is important for both East Asian and non-East Asian populations wherever they live in the World.In this review, we introduce the biological features of lipoproteins and lipoprotein cholesterol and the evidence for their association with risk of ASCVD in East Asian and European populations. We also provide an overview of guideline recommendations for prevention of ASCVD in these two different world regions. Finally, specific preventive strategies and future perspectives are touched upon.

The Role of Remnant Cholesterol Beyond Low-Density Lipoprotein Cholesterol in Arterial Stiffness: A Cross-Sectional Study

Background: Previous evidence has demonstrated that elevated low-density lipoprotein cholesterol (LDL-C) was associated with atherosclerosis. However, there is scarce population-based evidence for the role of remnant cholesterol (remnant-C) in arterial stiffness, an imaging marker for subclinical atherosclerosis. Herein, we aimed to evaluate the correlation of remnant-C with arterial stiffness beyond LDL-C in a check-up population. Methods: The study included consecutive subjects who visited the Murakami Memorial Hospital for health check-ups between 2004 and 2012. The calculation of remnant-C occurred as total cholesterol minus high-density lipoprotein cholesterol (HDL-C) minus LDL-C. The brachial-ankle pulse wave velocity (baPWV) >1400 cm/sec was defined as arterial stiffness or baPWV abnormality. The independent correlation of remnant-C level to arterial stiffness was evaluated using adjusted regression models. Results: A total of 909 participants were included (mean age 51.1 ± 9.6 years, male sex 64.9%). In multivariate linear regression analyses, remnant-C remained an independent predictor of the baPWV predictor [β: 94.76, 95% confidence interval (CI) 42.19-147.33, P < 0.001] after adjusting for confounders. After multivariable adjustment, including LDL-C, the highest remnant-C quartile odd ratio (OR) (95% CI) was 2.79 (1.27-6.09) for baPWV abnormality compared to the lowest quartile. Furthermore, each 10-mg/dL increase in remnant-C correlated with a 28% increased risk for baPWV abnormality (OR: 1.28, 95% CI: 1.04-1.57). Moreover, the correlation between remnant-C and baPWV abnormality was still significant in the participant subgroup with optimal levels of LDL-C. Conclusions: Our findings demonstrated that remnant-C levels correlated to arterial stiffness with the dependence of LDL-C and other cardiovascular risk factors in a check-up population.

Use of Coronary Artery Calcium Quantification and Distribution for Coronary Vascular Disease Risk Reclassification in a Primary Prevention Setting

In a large screening program of asymptomatic middle-aged individuals, we sought to assess the degree of risk reclassification provided by comparing multiethnic study on subclinical atherosclerosis coronary artery calcium scoring (CACS) versus atherosclerotic cardiovascular disease (ASCVD) and Reynolds risk score (RRS) score. All 5,324 consecutive patients (aged 57 ± 8 years, 76% male) who underwent CACS screening at the Cleveland Clinic as part of a primary prevention executive health between March 16 and October 21 were included. The 10-year ASCVD, RRS, and multiethnic study on subclinical atherosclerosis CACS (MESA-CACS) risk scores were calculated and categorized as <1, 1 to 4.99, 5 to 9.99, and ≥10%. Compared with ASCVD, using MESA-CACS resulted in a downgraded risk in 1,667 subjects (31%), whereas 738 (14%) had an upgrade in risk (total of 45% reclassification). Similarly, compared with RRS, using MESA-CACS resulted in an upgraded risk in 797 (15%) and a downgrade in 1,380 (26%) subjects (total of 41% reclassification). However, by further dividing by the distribution of the coronary calcification, ASCVD overestimates the risk only for patients with coronary artery calcium (CAC) in 0 or 1 coronary artery only, whereas MESA-CACS overestimates if the CAC was noted in ≥2 arteries. Similarly, RRS only overestimates the risk for patients with 0 CAC, whereas it underestimates the risk for patients with any CAC. In conclusion, the use of MESA-CACS, along with CAC distribution in primary prevention clinics, results in differential and significant reclassification of traditional scores when calculating the 10-years coronary vascular disease risk. Overall, RRS underestimates and ASCVD overestimates the cardiovascular disease risk compared with MESA-CACS.

Inflammatory Cell-Derived MYDGF Attenuates Endothelial LDL Transcytosis to Protect Against Atherogenesis

BACKGROUND

Inflammation contributes to the pathogenesis of atherosclerosis. But little is known about the potential benefits of inflammatory cells to atherosclerosis. The aim of this study was to investigate the function of inflammatory cells/endothelium axis and determine whether and how inflammatory cell-derived MYDGF (myeloid-derived growth factor) inhibited endothelial LDL (low-density lipoprotein) transcytosis.

METHODS

In in vivo experiments, both loss- and gain-of-function strategies were used to evaluate the effect of inflammatory cell-derived MYDGF on LDL transcytosis. We generated monocyte/macrophage-targeted MYDGF-null mice on an Ldlr (LDL receptor)-/- background in the loss-of-function strategy and restored the inflammatory cell-derived MYDGF by bone marrow transplantation and inflammatory cell-specific overexpression of MYDGF mice model in the gain-of-function strategy. In in vitro experiments, coculture experiments between primary mouse aortic endothelial cells and macrophages and mouse aortic endothelial cells supplemented with or without recombinant MYDGF were conducted.

RESULTS

Inflammatory cell-derived MYDGF deficiency aggravated endothelial LDL transcytosis, drove LDL uptake by artery wall, and thus exacerbated atherosclerosis in vivo. Inflammatory cell-derived MYDGF restoration by bone marrow transplantation and inflammatory cell MYDGF overexpression alleviated LDL transport across the endothelium, prevented LDL accumulation in the subendothelial space, and subsequently ameliorated atherosclerosis in vivo. Furthermore, in the in vitro study, macrophages isolated from MYDGF+/+ mice and recombinant MYDGF attenuated LDL transcytosis and uptake in mouse aortic endothelial cells. Mechanistically, MYDGF inhibited MAP4K4 (mitogen-activated protein kinase kinase kinase kinase isoform 4) phosphorylation, enhanced activation of Akt (protein kinase B)-1, and diminished the FoxO (forkhead box O) 3a signaling cascade to exert protective effects of MYDGF on LDL transcytosis and atherosclerosis.

CONCLUSIONS

The findings support a role for inflammatory cell-derived MYDGF served as a cross talk factor between inflammatory cells and endothelial cells that inhibits LDL transcytosis across endothelium. MYDGF may become a novel therapeutic drug for atherosclerosis, and the beneficial effects of inflammatory cell in atherosclerosis deserve further attention.

LDL binding to cell receptors and extracellular matrix is proatherogenic in obesity but improves after bariatric surgery

Obesity is a major global public health issue involving dyslipidemia, oxidative stress, inflammation, and increased risk of CVD. Weight loss reduces this risk, but the biochemical underpinnings are unclear. We explored how obesity and weight loss after bariatric surgery influence LDL interactions that trigger proatherogenic versus antiatherogenic processes. LDL was isolated from plasma of six patients with severe obesity before (basal) and 6-12 months after bariatric surgery (basal BMI = 42.7 kg/m2; 6-months and 12-months postoperative BMI = 34.1 and 30 kg/m2). Control LDL were from six healthy subjects (BMI = 22.6 kg/m2). LDL binding was quantified by ELISA; LDL size and charge were assessed by chromatography; LDL biochemical composition was determined. Compared to controls, basal LDL showed decreased nonatherogenic binding to LDL receptor, which improved postoperatively. Conversely, basal LDL showed increased binding to scavenger receptors LOX1 and CD36 and to glycosaminoglycans, fibronectin and collagen, which is proatherogenic. One year postoperatively, this binding decreased but remained elevated, consistent with elevated lipid peroxidation. Serum amyloid A and nonesterified fatty acids were elevated in basal and postoperative LDL, indicating obesity-associated inflammation. Aggregated and electronegative LDL remained elevated, suggesting proatherogenic processes. These results suggest that obesity-induced inflammation contributes to harmful LDL alterations that probably increase the risk of CVD. We conclude that in obesity, LDL interactions with cell receptors and extracellular matrix shift in a proatherogenic manner but are partially reversed upon postoperative weight loss. These results help explain why the risk of CVD increases in obesity but decreases upon weight loss.

Remnant cholesterol predicts cardiovascular mortality beyond low-density lipoprotein cholesterol in patients with peritoneal dialysis

BACKGROUND

Patients undergoing peritoneal dialysis (PD) are prone to dyslipidemia. However, studies concerning remnant cholesterol (RC) in such patients are limited.

OBJECTIVE

We aimed to investigate the association between RC and cardiovascular (CV) mortality in patients on PD.

METHODS

Patients who initiated PD at our center (2006-2018) were retrospectively enrolled. Adjusted Cox models were used to evaluate the independent association between baseline RC levels and CV mortality. We classified patients into 4 concordant/discordant categories according to their baseline lipid profiles. Cox models were then used to determine the association between different low-density lipoprotein cholesterol (LDL-C) and RC levels and CV mortality risk.

RESULTS

The study enrolled 2333 individuals, with a mean RC of 33.4 mg/dL. RC levels were positively associated with CV mortality risk independent of LDL-C in patients on PD (hazard ratio [HR]: 1.05; 95% confidence interval [CI]: 1. 00-1.10). In the concordant/discordant categories, patients with high LDL-C and RC levels had a higher CV mortality risk (HR: 1.52; 95% CI: 1.01-2.28) than those with low LDL-C and RC levels in the entire cohort. Moreover, in older patients, a higher RC level increased CV mortality risk regardless of the LDL-C level (HR: 2.41, 95% CI: 1.22-4.74; HR: 2.15, 95% CI: 1.12-4.14).

CONCLUSIONS

RC levels are elevated in patients on PD and can predict CV mortality beyond LDL-C levels. RC levels should be considered alongside LDL-C levels when assessing prognostic lipid levels in these patients. More attention should be given to RC than to LDL-C in older patients undergoing PD.

Triglyceride-rich lipoprotein remnants, low-density lipoproteins, and risk of coronary heart disease: a UK Biobank study

AIMS

The strength of the relationship of triglyceride-rich lipoproteins (TRL) with risk of coronary heart disease (CHD) compared with low-density lipoprotein (LDL) is yet to be resolved.

METHODS AND RESULTS

Single-nucleotide polymorphisms (SNPs) associated with TRL/remnant cholesterol (TRL/remnant-C) and LDL cholesterol (LDL-C) were identified in the UK Biobank population. In a multivariable Mendelian randomization analysis, TRL/remnant-C was strongly and independently associated with CHD in a model adjusted for apolipoprotein B (apoB). Likewise, in a multivariable model, TRL/remnant-C and LDL-C also exhibited independent associations with CHD with odds ratios per 1 mmol/L higher cholesterol of 2.59 [95% confidence interval (CI): 1.99-3.36] and 1.37 [95% CI: 1.27-1.48], respectively. To examine the per-particle atherogenicity of TRL/remnants and LDL, SNPs were categorized into two clusters with differing effects on TRL/remnant-C and LDL-C. Cluster 1 contained SNPs in genes related to receptor-mediated lipoprotein removal that affected LDL-C more than TRL/remnant-C, whereas cluster 2 contained SNPs in genes related to lipolysis that had a much greater effect on TRL/remnant-C. The CHD odds ratio per standard deviation (Sd) higher apoB for cluster 2 (with the higher TRL/remnant to LDL ratio) was 1.76 (95% CI: 1.58-1.96), which was significantly greater than the CHD odds ratio per Sd higher apoB in cluster 1 [1.33 (95% CI: 1.26-1.40)]. A concordant result was obtained by using polygenic scores for each cluster to relate apoB to CHD risk.

CONCLUSION

Distinct SNP clusters appear to impact differentially on remnant particles and LDL. Our findings are consistent with TRL/remnants having a substantially greater atherogenicity per particle than LDL.

Early steps in the birth of four membrane-bound organelles-Peroxisomes, lipid droplets, lipoproteins, and autophagosomes

Membrane-bound organelles allow cells to traffic cargo and separate and regulate metabolic pathways. While many organelles are generated by the growth and division of existing organelles, some can also be produced de novo, often in response to metabolic cues. This review will discuss recent advances in our understanding of the early steps in the de novo biogenesis of peroxisomes, lipid droplets, lipoproteins, and autophagosomes. These organelles play critical roles in cellular lipid metabolism and other processes, and their dysfunction causes or is linked to several human diseases. The de novo biogenesis of these organelles occurs in or near the endoplasmic reticulum membrane. This review summarizes recent progress and highlights open questions.

Reassessing the Effects of Dietary Fat on Cardiovascular Disease in China: A Review of the Last Three Decades

Cardiovascular disease (CVD) is a leading cause of global mortality, and is considered one of diseases with the most rapid growth rate in China. Numerous studies have indicated a closed relationship between an increased incidence of CVD and dietary factors. Dietary fat is one of the three primary nutrients of consumption; however, high fat dietary in causing CVD has been neglected in some official dietary guidelines. Our present review has analyzed the relationship between dietary fat consumption and CVD in China over the past 30 years (from 1990 to 2019). There is a significant correlation between CVD incidence and mortality for consumption of both vegetable oils and animal fats, per capita consumption, and the relative weight of dietary fat exceeding that of other food ingredients (e.g., salt, fruit, and marine food). For fatty acid species, the proportion of ω6 fatty acid consumption increased, causing a significant increase in the ratios of ω6/ω3 fatty acids, whereas the proportion of monounsaturated fatty acid consumption decreased. Such changes have been considered a characteristic of dietary fat consumption in Chinese residents over the past 30 years, and are closely related to the incidence of CVD. Therefore, we suggest that the government should spread awareness regarding the consumption of dietary fat intake to prevent CVD and related health disorders. The public should be educated to avoid high fat diet and increase the intake of monounsaturated fatty acids and ω3 fatty acids.

The Prognostic Significance of Leukocyte Count on All-Cause and Cardiovascular Disease Mortality: A Systematic Review and Meta-Analysis

White blood cells (WBCs) act as mediators of inflammatory responses and are commonly measured in hospitals. Although several studies have reported a relation between WBC count and mortality, no systematic review or meta-analysis has been conducted. This study aimed to identify an association between WBC count and mortality. We conducted a systematic search on Embase using keywords such as "white blood cell" and "mortality." We analyzed the hazard ratios (HRs) for WBC count of 1.0 × 109 cells/L regarding 2 criteria: the cause of mortality and the follow-up period. A total of 13 of 222 articles comprising a total of 62,904 participants were included in this study, meeting the criteria set. A positive association was observed between WBC count and mortality, as indicated by an HR of 1.10 (95% confidence interval [CI] 1.08 to 1.13). In additionally, WBC count emerged as a significant predictor of mortality in both groups, with an HR of 1.10 (95% CI 1.07 to 1.12) for patients with cardiovascular disease and an HR of 1.12 (95% CI 1.07 to 1.17) for the general population or patients with COVID-19. Furthermore, a higher WBC count demonstrated a significant association with long-term all-cause mortality (HR 1.09, 95% CI 1.07 to 1.12) and long-term cardiovascular mortality (HR 1.05, 95% CI 1.02 to 1.07). Similarly, a significant association was found between higher WBC count and short-term all-cause mortality (HR 1.12, 95% CI 1.09 to 1.16) and cardiovascular mortality (HR 1.12, 95% CI 1.07 to 1.17). Further research is necessary to explore the relation between WBC count and disease progression or death and to establish causality between elevated WBC count and disease progression.

Role of inflammation and immune response in atherosclerosis: Mechanisms, modulations, and therapeutic targets

Cardiovascular diseases (CVDs) have emerged as the leading cause of mortality globally, with atherosclerosis being a prominent focus of investigation among medical researchers worldwide. Atherosclerosis is characterized as a disease of the large and medium-sized arteries that is multifocal, accumulative, and immunoinflammatory in nature, resulting from the deposition of lipids. Accumulating evidence suggests that inflammatory responses and immunoregulation play a vital role in the occurrence and development of atherosclerosis. While existing treatments for atherosclerosis can assist in symptom management and slowing disease progression, a complete cure remains elusive. Consequently, there is significant interest in research and development of potential new drugs for this condition. Therefore, this review aims to consolidate the current understanding of the pathogenesis of atherosclerosis with an emphasis on inflammation, immune response and infection. Besides, it examines the effects and mechanisms of immunological modulations in atherosclerosis, and the potential therapeutic targets and drugs for intervening in the inflammatory responses and immunoregulation associated with atherosclerosis. Additionally, novel drug options for treating atherosclerosis are explored within the context of this review.

Membrane Cholesterol Interactions with Proteins in Hypercholesterolemia-Induced Endothelial Dysfunction

PURPOSE OF REVIEW

The goal of this review is to highlight work identifying mechanisms driving hypercholesterolemia-mediated endothelial dysfunction. We specifically focus on cholesterol-protein interactions and address specific questions related to the impact of hypercholesterolemia on cellular cholesterol and vascular endothelial function. We describe key approaches used to determine the effects of cholesterol-protein interactions in mediating endothelial dysfunction under dyslipidemic conditions.

RECENT FINDINGS

The benefits of removing the cholesterol surplus on endothelial function in models of hypercholesterolemia is clear. However, specific mechanisms driving cholesterol-induced endothelial dysfunction need to be determined. In this review, we detail the latest findings describing cholesterol-mediated endothelial dysfunction, highlighting our studies indicating that cholesterol suppresses endothelial Kir2.1 channels as a major underlying mechanism. The findings detailed in this review support the targeting of cholesterol-induced suppression of proteins in restoring endothelial function in dyslipidemic conditions. The identification of similar mechanisms regarding other cholesterol-endothelial protein interactions is warranted.

Intracellular tPA-PAI-1 interaction determines VLDL assembly in hepatocytes

Apolipoprotein B (apoB)-lipoproteins initiate and promote atherosclerotic cardiovascular disease. Plasma tissue plasminogen activator (tPA) activity is negatively associated with atherogenic apoB-lipoprotein cholesterol levels in humans, but the mechanisms are unknown. We found that tPA, partially through the lysine-binding site on its Kringle 2 domain, binds to the N terminus of apoB, blocking the interaction between apoB and microsomal triglyceride transfer protein (MTP) in hepatocytes, thereby reducing very-low-density lipoprotein (VLDL) assembly and plasma apoB-lipoprotein cholesterol levels. Plasminogen activator inhibitor 1 (PAI-1) sequesters tPA away from apoB and increases VLDL assembly. Humans with PAI-1 deficiency have smaller VLDL particles and lower plasma levels of apoB-lipoprotein cholesterol. These results suggest a mechanism that fine-tunes VLDL assembly by intracellular interactions among tPA, PAI-1, and apoB in hepatocytes.

AGEs promote atherosclerosis by increasing LDL transcytosis across endothelial cells via RAGE/NF-κB/Caveolin-1 pathway

OBJECTIVE

To elucidate the mechanism whereby advanced glycation end products (AGEs) accelerate atherosclerosis (AS) and to explore novel therapeutic strategies for atherosclerotic cardiovascular disease.

METHODS AND RESULTS

The effect of AGEs on low-density lipoprotein (LDL) transcytosis across endothelial cells (ECs) was assessed using an in vitro model of LDL transcytosis. We observed that AGEs activated the receptor for advanced glycation end products (RAGE) on the surface of ECs and consequently upregulated Caveolin-1, which in turn increased caveolae-mediated LDL transcytosis and accelerated AS progression. Our molecular assessment revealed that AGEs activate the RAGE-NF-κB signaling, which then recruits the NF-κB subunit p65 to the RAGE promoter and consequently enhances RAGE transcription, thereby forming a positive feedback loop between the NF-κB signaling and RAGE expression. Increased NF-κB signaling ultimately upregulated Caveolin-1, promoting LDL transcytosis, and inhibition of RAGE suppressed AGE-induced LDL transcytosis. In ApoE-/- mice on a high-fat diet, atherosclerotic plaque formation was accelerated by AGEs but suppressed by EC-specific knockdown of RAGE.

CONCLUSION

AGEs accelerate the development of diabetes-related AS by increasing the LDL transcytosis in ECs through the activation of the RAGE/NF-κB/Caveolin-1 axis, which may be targeted to prevent or treat diabetic macrovascular complications.

Knowledge fields and emerging trends about extracellular matrix in carotid artery disease from 1990 to 2021: analysis of the scientific literature

BACKGROUND

Stroke is a heavy burden in modern society, and carotid artery disease is a major cause. The role of the extracellular matrix (ECM) in the development and progression of carotid artery disease has become a popular research focus. However, there is no published bibliometric analysis to derive the main publication features and trends in this scientific area. We aim to conduct a bibliometric analysis to reveal current status of ECM in carotid artery disease and to predict future hot spots.

METHODS

We searched and downloaded articles from the Web of Science Core Collection with "Carotid" and "Extracellular Matrix" as subject words from 1990 to 2021. The complete bibliographic data were analyzed by Bibliometrics, BICOMB, gCLUTO and CiteSpace softwares.

RESULTS

Since 1990, the United States has been the leader in the number of publications in the field of ECM in carotid artery disease, followed by China, Japan and Germany. Among institutions, Institut National De La Sante Et De La Recherche Medicale Inserm, University of Washington Seattle and Harvard University are in the top 3. "Arteriosclerosis Thrombosis and Vascular Biology" is the most popular journal and "Circulation" is the most cited journal. "Clowes AW", "Hedin Ulf" and "Nilsson Jan" are the top three authors of published articles. Finally, we investigated the frontiers through the strongest citation bursts, conducted keyword biclustering analysis, and discovered five clusters of research hotspots. Our research provided a comprehensive analysis of the fundamental data, knowledge organization, and dynamic evolution of research about ECM in carotid artery disease.

CONCLUSIONS

The field of ECM in carotid artery disease has received increasing attention. We summarized the history of the field and predicted five future hotspots through bibliometric analysis. This study provided a reference for researchers in this fields, and the methodology can be extended to other fields.

A Lipid-Structured Model of Atherosclerotic Plaque Macrophages with Lipid-Dependent Kinetics

Atherosclerotic plaques are fatty growths in artery walls that cause heart attacks and strokes. Plaque formation is driven by macrophages that are recruited to the artery wall. These cells consume and remove blood-derived lipids, such as modified low-density lipoprotein. Ineffective lipid removal, due to macrophage death and other factors, leads to the accumulation of lipid-loaded macrophages and formation of a necrotic lipid core. Experimental observations suggest that macrophage functionality varies with the extent of lipid loading. However, little is known about the influence of macrophage lipid loads on plaque fate. Extending work by Ford et al. (J Theor Biol 479:48-63, 2019) and Chambers et al. (A lipid-structured model of atherosclerosis with macrophage proliferation, 2022), we develop a plaque model where macrophages are structured by their ingested lipid load and behave in a lipid-dependent manner. The model considers several macrophage behaviours, including recruitment to and emigration from the artery wall; proliferation and apotosis; ingestion of plaque lipids; and secondary necrosis of apoptotic cells. We consider apoptosis, emigration and proliferation to be lipid-dependent and we model these effects using experimentally informed functions of the internalised lipid load. Our results demonstrate that lipid-dependent macrophage behaviour can substantially alter plaque fate by changing both the total quantity of lipid in the plaque and the distribution of lipid between the live cells, dead cells and necrotic core. The consequences of macrophage lipid-dependence are often unpredictable because lipid-dependent effects introduce subtle, nonlinear interactions between the modelled cell behaviours. These observations highlight the importance of mathematical modelling in unravelling the complexities of macrophage lipid accumulation during atherosclerotic plaque formation.

Integrated Cascade Nanozymes with Antisenescence Activities for Atherosclerosis Therapy

Senescent cells are the critical drivers of atherosclerosis formation and maturation. Mitigating senescent cells holds promise for the treatment of atherosclerosis. In an atherosclerotic plaque microenvironment, senescent cells interact with reactive oxygen species (ROS), promoting the disease development. Here, we hypothesize that a cascade nanozyme with antisenescence and antioxidant activities can serve as an effective therapeutic for atherosclerosis. An integrated cascade nanozyme with superoxide dismutase- and glutathione peroxidase-like activities, named MSe1 , is developed in this work. The obtained cascade nanozyme can attenuate human umbilical vein endothelial cell (HUVEC) senescence by protecting DNA from damage. It significantly weakens inflammation in macrophages and HUVECs by eliminating overproduced intracellular ROS. Additionally, the MSe1 nanozyme effectively inhibits foam cell formation in macrophages and HUVECs by decreasing the internalization of oxidized low-density lipoprotein. After intravenous administration, the MSe1 nanozyme significantly inhibits the formation of atherosclerosis in apolipoprotein E-deficient (ApoE-/- ) mice by reducing oxidative stress and inflammation and then decreases the infiltration of inflammatory cells and senescent cells in atherosclerotic plaques. This study not only provides a cascade nanozyme but also suggests that the combination of antisenescence and antioxidative stress holds considerable promise for treating atherosclerosis.

Role of Circular RNAs in Atherosclerosis through Regulation of Inflammation, Cell Proliferation, Migration, and Apoptosis: Focus on Atherosclerotic Cerebrovascular Disease

Atherosclerosis (AS) is a disease dangerous to human health and the main pathological cause of ischemic cardiovascular diseases. Although its pathogenesis is not fully understood, numerous basic and clinical studies have shown that AS is a chronic inflammatory disease existing in all stages of atherogenesis. It may be a common link or pathway in the pathogenesis of multiple atherogenic factors. Inflammation is associated with AS complications, such as plaque rupture and ischemic cerebral infarction. In addition to inflammation, apoptosis plays an important role in AS. Apoptosis is a type of programmed cell death, and different apoptotic cells have different or even opposite roles in the process of AS. Unlike linear RNA, circular RNA (circRNA) a covalently closed circular non-coding RNA, is stable and can sponge miRNA, which can affect the stages of AS by regulating downstream pathways. Ultimately, circRNAs play very important roles in AS by regulating inflammation, apoptosis, and some other mechanisms. The study of circular RNAs can provide new ideas for the prediction, prevention, and treatment of AS.

Standardization of Apolipoprotein B, LDL-Cholesterol, and Non-HDL-Cholesterol

Concern continues about whether the measurement of apolipoprotein B (apoB) is adequately standardized, and therefore, whether apoB should be applied widely in clinical care. This concern is misplaced. Our objective is to explain why and what the term "standardization" means. To produce clinically valid results, a test must accurately, precisely, and selectively measure the marker of interest. That is, it must be standardized. Accuracy refers to how closely the result obtained with 1 method corresponds to the result obtained with the standard method, precision to how reproducible the result is on repeated testing, and selectivity to how susceptible the method is to error by inclusion of other classes of lipoprotein particles. Multiple expert groups have determined that the measurement of apoB is adequately standardized for clinical care, and that apoB can be measured inexpensively, using widely available automated methods, more accurately, precisely, and selectively than low-density lipoprotein cholesterol or non-high-density lipoprotein cholesterol. ApoB is a standard superior to low-density lipoprotein cholesterol and high-density lipoprotein cholesterol because it is a defined molecule, whereas the cholesterol markers are the mass of cholesterol within lipoprotein particles defined by their density, not by their molecular structure. Nevertheless, the standardization of apoB is being further improved by the application of mass spectrophotometric methods, whereas the limitations in the standardization and, therefore, the accurate, precise, and selective measurement of low-density lipoprotein cholesterol and high-density lipoprotein cholesterol are unlikely to be overcome. We submit that greater accuracy, precision, and selectivity in measurement is a decisive advantage for apoB in the modern era of intensive lipid-lowering therapies.

Detection and Imaging of Active Substances in Early Atherosclerotic Lesions Using Fluorescent Probes

Atherosclerosis (AS) is a vascular disease caused by chronic inflammation and lipids that is the main cause of myocardial infarction, stroke and other cardiovascular diseases. Atherosclerosis is often difficult to detect in its early stages due to the absence of clinically significant vascular stenosis. This is not conducive to early intervention or treatment of the disease. Over the past decade, researchers have developed various imaging methods for the detection and imaging of atherosclerosis. At the same time, more and more biomarkers are being found that can be used as targets for detecting atherosclerosis. Therefore, the development of a variety of imaging methods and a variety of targeted imaging probes is an important project to achieve early assessment and treatment of atherosclerosis. This paper provides a comprehensive review of the optical probes used to detect and target atherosclerosis imaging in recent years, and describes the current challenges and future development directions.

Administration of insulin like growth factor I (IGFI) lowers serum lipoprotein(a)-impact on atherosclerotic cardiovascular disease

Insulin like growth factor I (IGFI) secreted by the liver upon stimulation by pituitary growth hormone (GH) acts as the most important growth stimulating hormone in children. The present review presents evidence that among its additional metabolic effects, IGF-I suppresses the synthesis of lipoprotein(a) [Lp(a)], an independent risk factor for atherosclerotic cardiovascular disease. In view of this property, it is suggested that the addition of IGF-I to the armamentarium of hyperlipoproteinemia treatment should be considered.

Dickkopf-1 promotes vascular smooth muscle cell foam cell formation and atherosclerosis development through CYP4A11/SREBP2/ABCA1

Vascular smooth muscle cells (VSMCs) are considered to be a crucial source of foam cells in atherosclerosis due to their low expression level of cholesterol exporter ATP-binding cassette transporter A1 (ABCA1) intrinsically. While the definite regulatory mechanisms are complicated and have not yet been fully elucidated, we previously reported that Dickkopf-1 (DKK1) mediates endothelial cell (EC) dysfunction, thereby aggravating atherosclerosis. However, the role of smooth muscle cell (SMC) DKK1 in atherosclerosis and foam cell formation remains unknown. In this study, we established SMC-specific DKK1-knockout (DKK1SMKO ) mice by crossbreeding DKK1flox/flox mice with TAGLN-Cre mice. Then, DKK1SMKO mice were crossed with APOE-/- mice to generate DKK1SMKO /APOE-/- mice, which exhibited milder atherosclerotic burden and fewer SMC foam cells. In vitro loss- and gain-of-function studies of DKK1 in primary human aortic smooth muscle cells (HASMCs) have proven that DKK1 prevented oxidized lipid-induced ABCA1 upregulation and cholesterol efflux and promoted SMC foam cell formation. Mechanistically, RNA-sequencing (RNA-seq) analysis of HASMCs as well as chromatin immunoprecipitation (ChIP) experiments showed that DKK1 mediates the binding of transcription factor CCAAT/enhancer-binding protein delta (C/EBPδ) to the promoter of cytochrome P450 epoxygenase 4A11 (CYP4A11) to regulate its expression. In addition, CYP4A11 as well as its metabolite 20-HETE-promoted activation of transcription factor sterol regulatory element-binding protein 2 (SREBP2) mediated the DKK1 regulation of ABCA1 in SMC. Furthermore, HET0016, the antagonist of CYP4A11, has also shown an alleviating effect on atherosclerosis. In conclusion, our results demonstrate that DKK1 promotes SMC foam cell formation during atherosclerosis via a reduction in CYP4A11-20-HETE/SREBP2-mediated ABCA1 expression.

Adenosine signaling as target in cardiovascular pharmacology

Increasing evidence demonstrated the relevance of adenosine system in the onset and development of cardiovascular diseases, such as hypertension, myocardial infarct, ischemia, hypertension, heart failure, and atherosclerosis. In this regard, intense research efforts are being focused on the characterization of the pathophysiological significance of adenosine, acting at its membrane receptors named A1, A2A, A2B, and A3 receptors, in cardiovascular diseases. The present review article provides an integrated and comprehensive overview about current clinical and pre-clinical evidence about the role of adenosine in the pathophysiology of cardiovascular diseases. Particular attention has been focused on current scientific evidence about the pharmacological ligands acting on adenosine pathway as useful tools to manage cardiovascular diseases.

Macrophage-to-endothelial cell crosstalk by the cholesterol metabolite 27HC promotes atherosclerosis in male mice

Hypercholesterolemia and vascular inflammation are key interconnected contributors to the pathogenesis of atherosclerosis. How hypercholesterolemia initiates vascular inflammation is poorly understood. Here we show in male mice that hypercholesterolemia-driven endothelial activation, monocyte recruitment and atherosclerotic lesion formation are promoted by a crosstalk between macrophages and endothelial cells mediated by the cholesterol metabolite 27-hydroxycholesterol (27HC). The pro-atherogenic actions of macrophage-derived 27HC require endothelial estrogen receptor alpha (ERα) and disassociation of the cytoplasmic scaffolding protein septin 11 from ERα, leading to extranuclear ERα- and septin 11-dependent activation of NF-κB. Furthermore, pharmacologic inhibition of cyp27a1, which generates 27HC, affords atheroprotection by reducing endothelial activation and monocyte recruitment. These findings demonstrate cell-to-cell communication by 27HC, and identify a major causal linkage between the hypercholesterolemia and vascular inflammation that partner to promote atherosclerosis. Interventions interrupting this linkage may provide the means to blunt vascular inflammation without impairing host defense to combat the risk of atherosclerotic cardiovascular disease that remains despite lipid-lowering therapies.

Current Management of Highly Calcified Coronary Lesions: An Overview of the Current Status

The amount of coronary calcium strongly correlates with the degree of atherosclerosis and, therefore, with the rate of future cardiac events. Calcified coronary lesions still represent a challenge for interventional cardiologists, bringing not only a higher risk of immediate complications during percutaneous coronary interventions (PCI), but also a higher risk of late stent failure due to under-expansion and/or malapposition, and therefore, have a relevant prognostic impact. Accurate identification of the calcified plaques together with the analysis of their distribution pattern within the vessel wall by intracoronary imaging is important to improve the successful treatment of these lesions. The aim of this review is to guide readers through the assessment of the calcified plaque distribution using intracoronary imaging in order to select the best devices and strategies for plaque debulking and lesion preparation.

Lipid-laden foam cells in the pathology of atherosclerosis: shedding light on new therapeutic targets

INTRODUCTION

Lipid-laden foam cells within atherosclerotic plaques are key players in all phases of lesion development including its progression, necrotic core formation, fibrous cap thinning, and eventually plaque rupture. Manipulating foam cell biology is thus an attractive therapeutic strategy at early, middle, and even late stages of atherosclerosis. Traditional therapies have focused on prevention, especially lowering plasma lipid levels. Despite these interventions, atherosclerosis remains a major cause of cardiovascular disease, responsible for the largest numbers of death worldwide.

AREAS COVERED

Foam cells within atherosclerotic plaques are comprised of macrophages, vascular smooth muscle cells, and other cell types which are exposed to high concentrations of lipoproteins accumulating within the subendothelial intimal layer. Macrophage-derived foam cells are particularly well studied and have provided important insights into lipid metabolism and atherogenesis. The contributions of foam cell-based processes are discussed with an emphasis on areas of therapeutic potential and directions for drug development.

EXERT OPINION

As key players in atherosclerosis, foam cells are attractive targets for developing more specific, targeted therapies aimed at resolving atherosclerotic plaques. Recent advances in our understanding of lipid handling within these cells provide insights into how they might be manipulated and clinically translated to better treat atherosclerosis.

Discordantly high Apo B with LDL-C or non-HDL-C in relation to presence and burden of cerebral atherosclerotic plaques

BACKGROUND

Data are limited on associations between apolipoprotein B (Apo B) and cerebral atherosclerosis.

OBJECTIVE

Our study aimed to estimate associations between discordant Apo B with low-density lipoprotein cholesterol (LDL-C) or non-high-density lipoprotein cholesterol (Non-HDL-C) and the odds of the presence and burden of intra-/extra-cranial atherosclerotic plaques.

METHODS

This cross-sectional study was based on the baseline survey from the PolyvasculaR Evaluation for Cognitive Impairment and vaScular Events (PRECISE) study, a population-based prospective cohort study. Participants with complete baseline data but without taking lipid-lowering medication were included in this analysis. Discordant Apo B with LDL-C or Non-HDL-C were defined by residuals and cut-off values (LDL-C: 3.4 mmol/L, Non-HDL-C: 4.1 mmol/L). We used binary and ordinal logistic regression models to explore associations between discordant Apo B with LDL-C or Non-HDL-C and the presence and burden of intra-/extra-cranial atherosclerotic plaques.

RESULTS

A total of 2,943 participants were enrolled in this study. Discordantly high Apo B with LDL-C was associated with an increased odds of the presence of intracranial atherosclerotic plaque [odds ratio (OR),1.28; 95%CI,1.01-1.61], intracranial atherosclerotic burden [common odds ratio (cOR), 1.31; 95%CI,1.04-1.64], the presence of extracranial atherosclerotic plaque (OR, 1.37; 95%CI,1.14-1.66), and extracranial atherosclerotic burden (cOR, 1.32; 95%CI,1.10-1.58) compared with the concordant group. Discordantly low Apo B with Non-HDL-C was associated with decreased odds of the presence and burden of intra-/extra-cranial atherosclerotic plaques.

CONCLUSION

Discordantly high Apo B with LDL-C or Non-HDL-C were associated with an increased odds of the presence and burden of intra-/extra-cranial atherosclerotic plaques. This demonstrated that discordantly high Apo B might be important for early assessment of risk of cerebral atherosclerotic plaques in addition to LDL-C and Non-HDL-C.

Apolipoprotein Particle and Cardiovascular Risk Prediction (from a Prospective Cohort Study)

The present study aimed to examine the association between discordant apolipoprotein B (Apo B) with low-density lipoprotein cholesterol (LDL-C) or non-high-density lipoprotein cholesterol (non-HDL-C) and cardiovascular disease (CVD) risk in the Chinese population and to determine whether adding information on Apo B to LDL-C and HDL-C improves CVD risk prediction. This study collected data from the China Health and Nutrition Survey from 2009 to 2015. Discordant Apo B with LDL-C and non-HDL-C were defined based on residual differences and medians. Logistic regression was used to examine the association between discordant Apo B with LDL-C or non-HDL-C and CVD risk. Areas under the receiver operating characteristic curve and categorical net reclassification improvement were utilized to assess the incremental predictive value of Apo B levels for CVD risk. A total of 7,117 participants were included, the mean age was 50.8 ± 14.3 years, 53.6% were female. During the 6-year follow-up, 207 CVD cases were identified. Participants with discordant high Apo B relative to LDL-C or non-HDL-C were at higher risk of CVD than those with the concordant group (odds ratio 1.38, 95% confidence interval 1.01 to 1.87; odds ratio 1.40, 95% confidence interval 1.01 to 1.94, respectively). However, Apo B had no significant contribution to the predictive value of the China atherosclerotic CVD (ASCVD) risk score (areas under the receiver operating characteristic curve 0.788 for China ASCVD score alone vs 0.790 for China ASCVD score plus Apo B). In conclusion, Apo B has the strongest association with CVD risk in healthy Chinese participants than LDL-C and non-HDL-C. However, it has minimal value in CVD risk assessment and discrimination.

Serum amyloid A and interleukin -1β facilitate LDL transcytosis across endothelial cells and atherosclerosis via NF-κB/caveolin-1/cavin-1 pathway

BACKGROUND AND AIMS

Inflammatory molecules play important roles in atherosclerosis. We aimed to illustrate the roles of serum amyloid A (SAA), and interleukin (IL)-1β in low density lipoproteins (LDL) transcytosis and atherosclerosis.

METHODS

Effects of SAA and IL-1β on transcytosis of LDL were measured by an in vitro LDL transcytosis model. NF-κB/caveolin-1/cavin-1 pathway activation was investigated by Western blots and ELISA. Effects of SAA and IL-1β on the retention of LDL in aorta of C57BL/6J mice were detected by IVIS spectrum. Effects of SAA and IL-1β on atherosclerosis in Apoe-/- mice were examined by Oil Red O staining.

RESULTS

SAA and IL-1β stimulated LDL transcytosis across endothelial cells (ECs), which was accompanied by an increase in LDL uptake by ECs. SAA and IL-1β enhanced the activity of nuclear factor (NF)-κB, consequently facilitating an up-regulation of proteins involved in caveolae formation, including caveolin-1 and cavin-1, along with an assembly of NLRP3 inflammasome. Furthermore, SAA- and IL-1β-induced effects were blocked by NF-κB subunit p65 siRNA. Meanwhile, SAA- and IL-1β-induced LDL transcytosis were effectively blocked by caveolin-1 siRNA or cavin-1 siRNA. Interestingly, SAA and IL-1β facilitated LDL entering into the aorta of C57BL/6J mice. In Apoe-/- mice, SAA and IL-1β increased the areas of lipid-rich atherosclerotic lesions in the both ascending and root of aorta. Furthermore, a significant increase in the NLRP3 inflammasome, accompanied by accumulation of cavin-1 and caveolin-1, was observed in the aortic endothelium of Apoe-/- mice.

CONCLUSIONS

SAA and IL-1β accelerated LDL transcytosis via the NF-κB/caveolin-1/cavin-1 axis.

Cumulative non-high-density lipoprotein cholesterol burden and risk of atherosclerotic cardiovascular disease: a prospective community-based study

Background

The relationship between cumulative non-high-density lipoprotein cholesterol (non-HDL-C) burden and atherosclerotic cardiovascular disease (ASCVD) remains unclear.

Objective

To prospectively examine the association between cumulative non-HDL-C burden and ASCVD risk in the Kailuan cohort of China.

Methods

A total of 49,679 subjects who were free of ASCVD participated in three consecutive examinations in 2006, 2008 and 2010 were enrolled. Duration and concentration of cumulative exposure to non-HDL-C (cumNon-HDL-C) were respectively used to estimate the extent of cumulative non-HDL-C burden. The participants were divided into four groups according to durations of cumNon-HDL-C (0, 2, 4 and 6 years) and five groups according to the quintiles of cumNon-HDL-C concentration (<10.93, 10.93-12.68, 12.69-14.32, 14.33-16.72 and ≥16.73 mmol/L). Cox regression models were used to analyze the influence of cumulative non-HDL-C burden on ASCVD risk.

Results

We identified 1,134 incident ASCVD cases during a mean of 4.89 years of follow-up. Multivariable adjusted analysis revealed that compared with no exposure, cumNon-HDL-C duration 2, 4 and 6 years increased ASCVD risk by 26% (HR: 1.26, 95% CI: 1.07-1.47), 56% (HR: 1.56, 95% CI: 1.31-1.86) and 91% (HR: 1.91, 95% CI: 1.59-2.31) respectively; The hazard ratios (HRs) for the fourth and fifth versus lowest quintile of cumNon-HDL-C concentration were 1.25 and 1.72 for ASCVD. Each standard deviation increment in cumNon-HDL-C concentration was associated with a 10% increased risk of ASCVD.

Conclusion

Long-term and higher cumNon-HDL-C were all significantly associated with an increased risk of ASCVD independent of single non-HDL-C level.

Remnant cholesterol and risk of myocardial infarction in patients with coronary artery disease undergoing revascularization

BACKGROUND

Despite substantial reduction in low-density lipoprotein cholesterol (LDL-C), patients develop recurrent cardiovascular events. Remnant cholesterol (RC), the cholesterol content of triglyceride-rich lipoproteins, is a potential contributor to this residual risk.

OBJECTIVES

To investigate the association between RC and risk for myocardial infarction (MI) in patients with coronary artery disease, and examine whether the predictive value of RC is retained beyond non-high-density lipoprotein cholesterol (non-HDL-C).

METHODS

Data on 9451 patients undergoing coronary revascularization in a single center. RC was calculated as total cholesterol minus high-density lipoprotein cholesterol minus LDL-C (estimated using Martin-Hopkins equation). Cox-regression models were used to estimate the association between RC and risk for MI. Discordance analyses were performed to examine the correlation between RC and non-HDL-C (or LDL-C) in relation to MI risk.

RESULTS

Mean age was 65±11 years; 67% presented with acute coronary syndrome. During median follow-up of 9.6 years, 1690 patients developed MI. After multivariable adjustment including lipid-lowering therapies and non-HDL-C, RC was associated with higher MI risk: hazard ratio (95% confidence interval): 1.36 (1.20-1.56) and 1.58 (1.35-1.85) in those with RC levels ≥75th (32.6 mg/dL) and ≥90th (41.8 mg/dL) percentile, compared to RC <50th percentile (25.5 mg/dL). When RC and non-HDL-C (or LDL-C) levels were discordant, the level of RC better reflected the risk for MI.

CONCLUSIONS

Elevated RC is a risk factor for MI independent of lipid-lowering therapies and non-HDL-C, providing further support that RC may serve as a residual cardiovascular risk marker and potential treatment target in patients with coronary artery disease.

Effects of vitamin C supplementation on oxidative stress and serum paraoxonase/arylesterase activities in patients on long-term hemodialysis

BACKGROUND

Oxidative stress increases oxidizability of apolipoprotein-B containing lipoproteins and decreases paraoxonase (PON) activity in hemodialysis (HD) patients and plays an important part in the development of atherosclerotic cardiovascular diseases. In HD patients, plasma ascorbic acid (AA) levels are decreased either due to the loss by hemodialysis membranes or due to malnutrition and contribute to the imbalance of antioxidant defense mechanisms. We hypothesized that long-term ascorbic acid (AA) supplementation recovers oxidizability of lipoproteins in HD patients by reinforcing PON activity.

METHODS

Twenty-nine adult patients were treated with 100mg and 500mg AA at the end of each HD session thrice a week for two consecutive 16 weeks-periods, respectively. Blood samples were obtained before the first HD session and prior to the first HD sessions following the 100mg AA-supplemented and the 500mg AA-supplemented periods.

RESULTS

PON activities were significantly increased after 100mg (p<0.05) and 500mg AA (p<0.001) supplementation periods compared to the basal level. Apo-B lipoprotein oxidizability (Δ-MDA) was significantly decreased after 500mg AA supplementation compared to both basal (p<0.05) and 100mg AA supplementation periods (p<0.05). Plasma AA concentrations were negatively correlated with Δ-MDA levels (R=-0.327; p<0.01).

CONCLUSION

Our results suggest that long-term parenteral 500mg AA supplementation improves PON activity alleviating apo B-containing lipoproteins oxidizability in HD patients.

Arteriosclerosis Decreases Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand Expression on Liver Natural Killer Cells in Living Donor Liver Transplantation

BACKGROUND

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is critical for natural killer (NK) cell-mediated anti-tumor and anti-microbe killing. The TRAIL expression on the donor's liver NK cells from the liver perfusate after interleukin-2 stimulation varies between individuals and is unpredictable. This study aimed to clarify the risk factors for low TRAIL expression by analyzing perioperative donor characteristics.

METHODS

This retrospective study of living donor liver transplant (LDLT) donors between 2006 and 2022 was performed to analyze low TRAIL expression risk factors. Seventy-five donors who had undergone hepatectomy for LDLT were divided into 2 groups, low and high TRAIL, according to their TRAIL expression on liver NK cells, using median values.

RESULTS

The low TRAIL group (N = 38) was older and had lower nutrition and a higher low-density lipoprotein/high-density lipoprotein (LDL/HDL) cholesterol ratio, related to arteriosclerosis, than the high TRAIL group (N = 37). In multivariate analysis, the geriatric nutritional risk index (GNRI) (odds ratio, 0.86; 95% CI, 0.76-0.94; P < .001) and LDL/HDL cholesterol ratio (odds ratio, 2.32; 95% CI, 1.10-4.86; P = .005) were independent predictive factors for low TRAIL expression on liver NK cells. Furthermore, the TRAIL expression of liver NK cells decreased in donors who already had atherosclerosis and in donors at risk of potentially developing atherosclerosis.

CONCLUSIONS

The TRAIL expression on liver NK cells in donors had a strong relationship with atherosclerosis and GNRI. Atherosclerosis can reflect the TRAIL expression on liver NK cells.

Protective Effect of Olive Oil Microconstituents in Atherosclerosis: Emphasis on PAF Implicated Atherosclerosis Theory

Atherosclerosis is a progressive vascular multifactorial process. The mechanisms underlining the initiating event of atheromatous plaque formation are inflammation and oxidation. Among the modifiable risk factors for cardiovascular diseases, diet and especially the Mediterranean diet (MedDiet), has been widely recognized as one of the healthiest dietary patterns. Olive oil (OO), the main source of the fatty components of the MedDiet is superior to the other "Mono-unsaturated fatty acids containing oils" due to the existence of specific microconstituents. In this review, the effects of OO microconstituents in atherosclerosis, based on data from in vitro and in vivo studies with special attention on their inhibitory activity against PAF (Platelet-Activating Factor) actions, are presented and critically discussed. In conclusion, we propose that the anti-atherogenic effect of OO is attributed to the synergistic action of its microconstituents, mainly polar lipids that act as PAF inhibitors, specific polyphenols and α-tocopherol that also exert anti-PAF activity. This beneficial effect, also mediated through anti-PAF action, can occur from microconstituents extracted from olive pomace, a toxic by-product of the OO production process that constitutes a significant ecological problem. Daily intake of moderate amounts of OO consumed in the context of a balanced diet is significant for healthy adults.

Prospects of potential adipokines as therapeutic agents in obesity-linked atherogenic dyslipidemia and insulin resistance

BACKGROUND

In normal circumstances, AT secretes anti-inflammatory adipokines (AAKs) which regulates lipid metabolism, insulin sensitivity, vascular hemostasis, and angiogenesis. However, during obesity AT dysfunction occurs and leads to microvascular imbalance and secretes several pro-inflammatory adipokines (PAKs), thereby favoring atherogenic dyslipidemia and insulin resistance. Literature suggests decreased levels of circulating AAKs and increased levels of PAKs in obesity-linked disorders. Importantly, AAKs have been reported to play a vital role in obesity-linked metabolic disorders mainly insulin resistance, type-2 diabetes mellitus and coronary heart diseases. Interestingly, AAKs counteract the microvascular imbalance in AT and exert cardioprotection via several signaling pathways such as PI3-AKT/PKB pathway. Although literature reviews have presented a number of investigations detailing specific pathways involved in obesity-linked disorders, literature concerning AT dysfunction and AAKs remains sketchy. In view of the above, in the present contribution an effort has been made to provide an insight on the AT dysfunction and role of AAKs in modulating the obesity and obesity-linked atherogenesis and insulin resistance.

MAIN BODY

"Obesity-linked insulin resistance", "obesity-linked cardiometabolic disease", "anti-inflammatory adipokines", "pro-inflammatory adipokines", "adipose tissue dysfunction" and "obesity-linked microvascular dysfunction" are the keywords used for searching article. Google scholar, Google, Pubmed and Scopus were used as search engines for the articles.

CONCLUSIONS

This review offers an overview on the pathophysiology of obesity, management of obesity-linked disorders, and areas in need of attention such as novel therapeutic adipokines and their possible future perspectives as therapeutic agents.

Novel Aspects Targeting Platelets in Atherosclerotic Cardiovascular Disease—A Translational Perspective

Platelets are important cellular targets in cardiovascular disease. Based on insights from basic science, translational approaches and clinical studies, a distinguished anti-platelet drug treatment regimen for cardiovascular patients could be established. Furthermore, platelets are increasingly considered as cells mediating effects “beyond thrombosis”, including vascular inflammation, tissue remodeling and healing of vascular and tissue lesions. This review has its focus on the functions and interactions of platelets with potential translational and clinical relevance. The role of platelets for the development of atherosclerosis and therapeutic modalities for primary and secondary prevention of atherosclerotic disease are addressed. Furthermore, novel therapeutic options for inhibiting platelet function and the use of platelets in regenerative medicine are considered.

The Impact of the Blood Lipids Levels on Arterial Stiffness

Arterial stiffness is a recognized predictor of cardiovascular morbidity and death. It is an early indicator of arteriosclerosis and is influenced by numerous risk factors and biological processes. The lipid metabolism is crucial and standard blood lipids, non-conventional lipid markers and lipid ratios are associated with arterial stiffness. The objective of this review was to determine which lipid metabolism marker has a greater correlation with vascular aging and arterial stiffness. Triglycerides (TG) are the standard blood lipids that have the strongest associations with arterial stiffness, and are often linked to the early stages of cardiovascular diseases, particularly in patients with low LDL-C levels. Studies often show that lipid ratios perform better overall than any of the individual variables used alone. The relation between arterial stiffness and TG/HDL-C has the strongest evidence. It is the lipid profile of atherogenic dyslipidemia that is found in several chronic cardio-metabolic disorders, and is considered one of the main causes of lipid-dependent residual risk, regardless of LDL-C concentration. Recently, the use of alternative lipid parameters has also been increasing. Both non-HDL and ApoB are very well correlated with arterial stiffness. Remnant cholesterol is also a promising alternative lipid parameter. The findings of this review suggest that the main focus should be on blood lipids and arterial stiffness, especially in individuals with cardio-metabolic disorders and residual cardiovascular risk.