Endothelial Cell Dysfunction and the Pathobiology of Atherosclerosis

The impact of prediabetes and diabetes on endothelial function in a large population-based cohort

BACKGROUND

Diabetes and prediabetes are well-recognized risk factors for cardiovascular disease (CVD) and are marked by vascular endothelial dysfunction (ED). However, there is a scarcity of thorough population-based studies examining ED in individuals with diabetes/prediabetes free from manifest CVD. Here, we examined the association between ED assessed by reactive hyperaemia index (RHI) in the finger and diabetes/prediabetes in a large middle-aged population cohort.

METHODS

Within the Malmö Offspring Study, following the exclusion of participants <30 years and participants with prevalent CVD, 1384 participants had complete data on all covariates. The RHI was calculated using pulse amplitude tonometry. ED was defined as RHI < 1.67. Multivariable logistic and linear regression models were conducted to investigate associations between ED and RHI with diabetes and prediabetes.

RESULTS

The study population had a mean age of 53.6 ± 7.6 years (53% women). In study participants with manifest diabetes (n = 121) and prediabetes (n = 514), ED was present in 42% and 25% respectively, compared to 23% in those with normal glucometabolic status. In multivariable logistic regression analyses, prevalent diabetes was significantly associated with ED (OR 1.95; 95%CI 1.57-3.39; p = 0.002), as well as with lower RHI (β-coeff. -0.087; p = 0.002). However, prediabetes showed no association with neither ED nor RHI.

CONCLUSION

In a population free from CVD, vascular endothelial dysfunction was primarily associated with manifest diabetes, but not with prediabetes, implying that finger ED may develop when diabetes is established, rather than being an early sign of glucose intolerance. Further research is needed to explore whether addressing glucose intolerance could potentially delay or prevent vascular ED onset.

Mechanism of Zhishi Xiebai Guizhi decoction to treat atherosclerosis: Insights into experiments, network pharmacology and molecular docking

ETHNOPHARMACOLOGICAL RELEVANCE

Zhishi Xiebai Guizhi Decoction (ZSXBGZD) is a traditional herbal manuscript used to treat cardiovascular disease, including atherosclerosis and coronary heart disease. The decoction has demonstrated its capability to protect arteries and resist atherosclerosis. Its mechanisms for anti-atherosclerosis effect, nevertheless, remain unknown.

AIMS OF THE STUDY

The goal of the present study is to explore the effectiveness of ZSXBGZD acting on atherosclerosis and its key components based on experimental verification and network pharmacology analysis.

MATERIALS AND METHODS

The ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and databases were used to identify chemical components in ZSXBGZD. Network pharmacological analysis and molecular docking were implemented in order to reveal the possible therapeutic targets of ZSXBGZD. To form the model of atherosclerosis, we gave Apolipoprotein E knocked out mice a high-fat diet. H&E staining was performed to observe the effects of ZSXBGZD on atherosclerosis. Immunofluorescence and Western blot were used to investigate whether ZSXBGZD could affect autophagy, apoptosis, AGE-RAGE signaling pathway and other related mechanisms.

RESULTS

In total, 30 core compounds were screened through intersecting UPLC-Q-TOF-MS and the databases. The anti-atherosclerotic effect of ZSXBGZD might relate to the AGE-RAGE signaling pathway via network pharmacology analysis. ZSXBGZD could inhibit apoptosis, activate autophagy and ease inflammation by modifying AGE-RAGE signaling pathway to reduce the area of atherosclerotic plaque.

CONCLUSION

ZSXBGZD could treat atherosclerosis by regulating autophagy and apoptosis via adjusting the AGE-RAGE signaling pathway.

Endothelial dysfunction and cardiovascular diseases: The role of human induced pluripotent stem cells and tissue engineering

Cardiovascular disease (CVD) remains to be the leading cause of death globally today and therefore the need for the development of novel therapies has become increasingly important in the cardiovascular field. The mechanism(s) behind the pathophysiology of CVD have been laboriously investigated in both stem cell and bioengineering laboratories. Scientific breakthroughs have paved the way to better mimic cell types of interest in recent years, with the ability to generate any cell type from reprogrammed human pluripotent stem cells. Mimicking the native extracellular matrix using both organic and inorganic biomaterials has allowed full organs to be recapitulated in vitro. In this paper, we will review techniques from both stem cell biology and bioengineering which have been fruitfully combined and have fueled advances in the cardiovascular disease field. We will provide a brief introduction to CVD, reviewing some of the recent studies as related to the role of endothelial cells and endothelial cell dysfunction. Recent advances and the techniques widely used in both bioengineering and stem cell biology will be discussed, providing a broad overview of the collaboration between these two fields and their overall impact on tissue engineering in the cardiovascular devices and implications for treatment of cardiovascular disease.

Zinc finger translocation‑associated protein promotes ferroptosis through the upregulation of ACSL4 expression in vascular endothelial cells

Numerous studies have reported the potential involvement of ferroptosis in the development of atherosclerosis (AS). Acyl-CoA synthetase long chain family member 4 (ACSL4) is an essential component in the promotion of ferroptosis. The present study aimed to investigate the role of ACSL4 and zinc finger translocation-associated protein (ZFTA) in the regulation of endothelial cell ferroptosis in AS. Human umbilical vein endothelial cells (HUVECs) with ACSL4 knockout were generated using CRISPR/Cas9 technology. To assess ferroptosis, malondialdehyde concentration, iron content and reactive oxygen species levels were quantified in the present study. In addition, western blot analysis was conducted to explore the potential mechanisms underlying ACSL4 and ZFTA in the modulation of ferroptosis in HUVECs. The results of the present study demonstrated that the expression levels of ACSL4 and ZFTA were significantly increased in human atherosclerotic plaques. In addition, ACSL4 knockout led to a reduced susceptibility to ferroptosis, while ZFTA contributed to ferroptosis in HUVECs. Results of the present study also demonstrated that ZFTA overexpression upregulated ACSL4 expression in HUVECs, whereas ZFTA knockdown led to decreased ACSL4 expression. Co-transfection experiments demonstrated that the ZTFA overexpression-mediated increase in ferroptosis was reversed following ACSL4 knockdown. Collectively, results of the present study highlighted that ACSL4 mediated the effects of ZFTA on the ferroptosis of HUVECs. Thus, the present study demonstrated the potential role of ACSL4 and ZFTA in the regulation of ferroptosis, and highlighted that ferroptosis-related pathways may act as potential targets in the treatment of AS.

Interplay between epigenetic mechanisms and transcription factors in atherosclerosis

Cardiovascular diseases (CVD), including coronary heart disease and stroke, comprise the number one cause of mortality worldwide. A major contributor to CVD is atherosclerosis, which is a low-grade inflammatory disease of vasculature that involves a pathological build-up of plaque within the arterial walls. Studies have shown that regulation of gene expression via transcription factors and epigenetic mechanisms play a fundamental role in transcriptomic changes linked to the development of atherosclerosis. Chromatin remodeling is a reversible phenomenon and studies have supported the clinical application of chromatin-modifying agents for the prevention and treatment of CVD. In addition, pre-clinical studies have identified multiple transcription factors as potential therapeutic targets in combating atherosclerotic CVD. Although interaction between transcription factors and epigenetic mechanisms facilitate gene regulation, a limited number of studies appreciate this crosstalk in the context of CVD. Here, we reviewed this gene regulatory mechanism underappreciated in atherosclerosis, which will highlight the mechanisms underlying novel therapeutics targeting epigenetic modifiers and transcription factors in atherosclerosis.

Eicosapentaenoic Acid Improves Endothelial Nitric Oxide Bioavailability Via Changes in Protein Expression During Inflammation

BACKGROUND

Endothelial cell (EC) dysfunction involves reduced nitric oxide (NO) bioavailability due to NO synthase uncoupling linked to increased oxidation and reduced cofactor availability. Loss of endothelial function and NO bioavailability are associated with inflammation, including leukocyte activation. Eicosapentaenoic acid (EPA) administered as icosapent ethyl reduced cardiovascular events in REDUCE-IT (Reduction of Cardiovascular Events With Icosapent Ethyl-Intervention Trial) in relation to on-treatment EPA blood levels. The mechanisms of cardiovascular protection for EPA remain incompletely elucidated but likely involve direct effects on the endothelium.

METHODS AND RESULTS

In this study, human ECs were treated with EPA and challenged with the cytokine IL-6 (interleukin-6). Proinflammatory responses in the ECs were confirmed by ELISA capture of sICAM-1 (soluble intercellular adhesion molecule-1) and TNF-α (tumor necrosis factor-α). Global protein expression was determined using liquid chromatography-mass spectrometry tandem mass tag. Release kinetics of NO and peroxynitrite were monitored using porphyrinic nanosensors. IL-6 challenge induced proinflammatory responses from the ECs as evidenced by increased release of sICAM-1 and TNF-α, which correlated with a loss of NO bioavailability. ECs pretreated with EPA modulated expression of 327 proteins by >1-fold (P<0.05), compared with IL-6 alone. EPA augmented expression of proteins involved in NO production, including heme oxygenase-1 and dimethylarginine dimethylaminohydrolase-1, and 34 proteins annotated as associated with neutrophil degranulation. EPA reversed the endothelial NO synthase uncoupling induced by IL-6 as evidenced by an increased [NO]/[peroxynitrite] release ratio (P<0.05).

CONCLUSIONS

These direct actions of EPA on EC functions during inflammation may contribute to its distinct cardiovascular benefits.

Analysis of mechanism, therapeutic strategies, and potential natural compounds against atherosclerosis by targeting iron overload-induced oxidative stress

Ferroptosis is a novel form of cell demise characterized primarily by the reduction of trivalent iron to divalent iron, leading to the release of reactive oxygen species (ROS) and consequent induction of intense oxidative stress. In atherosclerosis (AS), highly accumulated lipids are modified by ROS to promote the formation of lipid peroxides, further amplifying cellular oxidative stress damage to influence all stages of atherosclerotic development. Macrophages are regarded as pivotal executors in the progression of AS and the handling of iron, thus targeting macrophage iron metabolism holds significant guiding implications for exploring potential therapeutic strategies against AS. In this comprehensive review, we elucidate the potential interplay among iron overload, inflammation, and lipid dysregulation, summarizing the potential mechanisms underlying the suppression of AS by alleviating iron overload. Furthermore, the application of Traditional Chinese Medicine (TCM) is increasingly widespread. Based on extant research and the pharmacological foundations of active compounds of TCM, we propose alternative therapeutic agents for AS in the context of iron overload, aiming to diversify the therapeutic avenues.

Bezafibrate mitigates oxidized-low density lipoprotein (ox-LDL)-induced the attachment of monocytes to endothelial cells: An implication in atherosclerosis

BACKGROUND

Oxidized forms of low-density lipoproteins (ox-LDL)-associated endothelial dysfunction and subsequent monocyte adhesion play an important role in the development of atherosclerosis (AS). Bezafibrate (BEZ) is a peroxisome proliferator-activated receptor (pan-PPAR) agonist licensed as a hypolipidemic drug. However, the effects of BEZ on endothelial dysfunction are less reported.

OBJECTIVES

In this study, we aim to investigate the protective effects of BEZ on ox-LDL-challenged vascular endothelial cells to evaluate its potential value in treating AS.

METHODS

Human aortic endothelial cells (HAECs) and THP-1 cells were used to establish an In Vitro AS model. Cell Counting Kit-8 (CCK-8) assay, Real-time PCR, Western blot analysis, and Enzyme-linked immunosorbent assay (ELISA) were used to test the data.

RESULTS

As expected, treatment with BEZ suppressed the expression of vascular endothelial growth factor A (VEGF-A), tissue factor (TF), Interleukin 12 (IL-12), tumor necrosis factor (TNF-α), and monocyte chemoattractant protein-1 (MCP-1). BEZ was also found to inhibit ox-LDL-induced expression of the endothelial adhesion molecules vascular cellular adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) in HAECs. Correspondingly, BEZ prevented attachment of THP-1 monocytes to ox-LDL-incubated HAECs. Mechanically, BEZ was found to prevent NF-κB activation by reducing the levels of nuclear NF-κB p65 and inhibiting luciferase activity of NF-κB.

CONCLUSION

Our study revealed the pharmacological function of BEZ in protecting endothelial dysfunction against ox-LDL, which may provide valuable insight for the clinical application of BEZ.

Unraveling the relationship among insulin resistance, IGF-1, and amyloid-beta 1-40: Is the definition of type 3 diabetes applicable in the cardiovascular field?

The concept of "type 3 diabetes" has emerged to define alterations in glucose metabolism that predispose individuals to the development of Alzheimer's disease (AD). Novel evidence suggests that changes in the insulin/insulin-like growth factor 1 (IGF-1)/growth hormone (GH) axis, which are characteristic of Diabetes Mellitus, are one of the major factors contributing to excessive amyloid-beta (Aβ) production and neurodegenerative processes in AD. Moreover, molecular findings suggest that insulin resistance and dysregulated IGF-1 signaling promote atherosclerosis via endothelial dysfunction and a pro-inflammatory state. As the pathophysiological role of Aβ1-40 in patients with cardiovascular disease has attracted attention due to its involvement in plaque formation and destabilization, it is of great interest to explore whether a paradigm similar to that in AD exists in the cardiovascular field. Therefore, this review aims to elucidate the intricate interplay between insulin resistance, IGF-1, and Aβ1-40 in the cardiovascular system and assess the applicability of the type 3 diabetes concept. Understanding these relationships may offer novel therapeutic targets and diagnostic strategies to mitigate cardiovascular risk in patients with insulin resistance and dysregulated IGF-1 signaling.

Metabolic Responses to Redox Stress in Vascular Cells

Significance: Redox stress underlies numerous vascular disease mechanisms. Metabolic adaptability is essential for vascular cells to preserve energy and redox homeostasis. Recent Advances: Single-cell technologies and multiomic studies demonstrate significant metabolic heterogeneity among vascular cells in health and disease. Increasing evidence shows that reductive or oxidative stress can induce metabolic reprogramming of vascular cells. A recent example is intracellular L-2-hydroxyglutarate accumulation in response to hypoxic reductive stress, which attenuates the glucose flux through glycolysis and mitochondrial respiration in pulmonary vascular cells and provides protection against further reductive stress. Critical Issues: Regulation of cellular redox homeostasis is highly compartmentalized and complex. Vascular cells rely on multiple metabolic pathways, but the precise connectivity among these pathways and their regulatory mechanisms is only partially defined. There is also a critical need to understand better the cross-regulatory mechanisms between the redox system and metabolic pathways as perturbations in either systems or their cross talk can be detrimental. Future Directions: Future studies are needed to define further how multiple metabolic pathways are wired in vascular cells individually and as a network of closely intertwined processes given that a perturbation in one metabolic compartment often affects others. There also needs to be a comprehensive understanding of how different types of redox perturbations are sensed by and regulate different cellular metabolic pathways with specific attention to subcellular compartmentalization. Lastly, integration of dynamic changes occurring in multiple metabolic pathways and their cross talk with the redox system is an important goal in this multiomics era.

Impact of dietary n-6/n-3 fatty acid ratio of atherosclerosis risk: A review

Atherosclerosis is a causative factor associated with cardiovascular disease (CVD). Over the past few decades, extensive research has been carried out on the relationship between the n-6/n-3 fatty acid ratio of ingested lipids and the progression of atherosclerosis. However, there are still many uncertainties regarding the precise nature of this relationship, which has led to challenges in providing sound dietary advice to the general public. There is therefore a pressing need to review our current understanding of the relationship between the dietary n-6/n-3 fatty acid ratio and atherosclerosis, and to summarize the underlying factors contributing to the current uncertainties. Initially, this article reviews the association between the n-6/n-3 fatty acid ratio and CVDs in different countries. A summary of the current understanding of the molecular mechanisms of n-6/n-3 fatty acid ratio on atherosclerosis is then given, including inflammatory responses, lipid metabolism, low-density lipoprotein cholesterol oxidation, and vascular function. Possible reasons behind the current controversies on the relationship between the n-6/n-3 fatty acid ratio and atherosclerosis are then provided, including the precise molecular structures of the fatty acids, diet-gene interactions, the role of fat-soluble phytochemicals, and the impact of other nutritional factors. An important objective of this article is to highlight areas where further research is needed to clarify the role of n-6/n-3 fatty acid ratio on atherosclerosis.

Increased risks of retinal vascular occlusion in patients with migraine and the protective effects of migraine treatment: a population-based retrospective cohort study

Associations between migraine and retinal vascular occlusion have been reported, but there is no large-scale and comprehensive study. Therefore, we aimed to determine risks of retinal vascular occlusion in patients with migraine. Using the Taiwan National Health Insurance Research Database from 2009 to 2020, we enrolled 628,760 patients with migraine and 628,760 matched individuals without migraine. Study outcomes were diagnoses of retinal vascular occlusion, including retinal artery occlusion (RAO) and retinal vein occlusion (RVO). Adjusted hazard ratio (aHR) of retinal vascular occlusion related to migraine was estimated. The cumulative incidences of subsequent retinal vascular occlusion, RAO, and RVO were significantly higher in migraine patients compared with controls (0.31% vs. 0.21%; 0.09% vs. 0.05%; 0.22% vs. 0.17%; all p < 0.001). The hazards of retinal vascular occlusion, RAO, and RVO were significantly greater in the migraine group (aHR, 1.69 [95% CI, 1.57, 1.83], 2.13 [95% CI, 1.84, 2.48] and 1.53 [95% CI, 1.40, 1.68], respectively). Risks of retinal vascular occlusion were significantly higher in migraine both with aura (MA) and without aura (MO) (aHR, 1.77 [95% CI, 1.58, 1.98], and 1.92 [95% CI, 1.64, 2.25]). Among patients with migraine, nonsteroidal anti-inflammatory drugs, propranolol, and flunarizine significantly reduce their risks of retinal vascular occlusion (aHR, 0.19 [95% CI, 0.16, 0.22], 0.73 [95% CI, 0.62, 0.86], 0.84 [95% CI, 0.76, 0.93]). Migraine, MA and MO are independently associated with higher risks of retinal vascular occlusion, RAO, and RVO.

Serum metabolic changes link metal mixture exposures to vascular endothelial inflammation in residents living surrounding rivers near abandoned lead-zinc mines

Metal exposure is associated with vascular endothelial inflammation, an early pathological phenotype of atherosclerotic cardiovascular events. However, the underlying mechanism linking exposure, metabolic changes, and outcomes remains unclear. We aimed to investigate the metabolic changes underlying the associations of chronic exposure to metal mixtures with vascular endothelial inflammation. We recruited 960 adults aged 20-75 years from residential areas surrounding rivers near abandoned lead-zinc mine and classified them into river area and non-river area exposure groups. Urine levels of 25 metals, Framingham risk score (FRS), and serum concentrations of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), as biomarkers of vascular endothelial inflammation, were assessed. A "meet-in-the-middle" approach was applied to identify causal intermediate metabolites and metabolic pathways linking metal exposure to vascular endothelial inflammation in representative metabolic samples from 64 participants. Compared to the non-river area exposure group, the river area exposure group had significantly greater urine concentrations of chromium, copper, cadmium, and lead; lower urine concentrations of selenium; elevated FRS; and increased concentrations of ICAM-1 and VCAM-1. In total, 38 differentially abundant metabolites were identified between the river area and non-river area exposure groups. Among them, 25 metabolites were significantly associated with FRS, 8 metabolites with ICAM-1 expression, and 10 metabolites with VCAM-1 expression. Furthermore, fructose, ornithine, alpha-ketoglutaric acid, urea, and cytidine monophosphate, are potential mediators of the relationship between metal exposure and vascular endothelial inflammation. Additionally, the metabolic changes underlying these effects included changes in arginine and proline metabolism, pyrimidine metabolism, starch and sucrose metabolism, galactose metabolism, arginine biosynthesis, and alanine, aspartate, and glutamate metabolism, suggesting the disturbance of amino acid metabolism, the tricarboxylic acid cycle, nucleotide metabolism, and glycolysis. Overall, our results reveal biomechanisms that may link chronic exposure to multiple metals with vascular endothelial inflammation and elevated cardiovascular risk.

Role of inflammasomes in endothelial dysfunction

The vascular endothelium dynamically responds to environmental cues and plays a pivotal role in maintaining vascular homeostasis by regulating vasomotor tone, blood cell trafficking, permeability and immune responses. However, endothelial dysfunction results in various pathological conditions. Inflammasomes are large intracellular multimeric complexes activated by pathogens or cellular damage. Inflammasomes in vascular endothelial cells (ECs) initiate innate immune responses, which have emerged as significant mediators in endothelial dysfunction, contributing to the pathophysiology of an array of diseases. This review summarizes the mechanisms and ramifications of inflammasomes in ECs and related vascular diseases such as atherosclerosis, abdominal aortic aneurysm, stroke, and lung and kidney diseases. We also discuss potential drugs targeting EC inflammasomes and their applications in treating vascular diseases.

Cracking the code of the cardiovascular enigma: hPSC-derived endothelial cells unveil the secrets of endothelial dysfunction

Endothelial dysfunction is a central contributor to the development of most cardiovascular diseases and is characterised by the reduced synthesis or bioavailability of the vasodilator nitric oxide together with other abnormalities such as inflammation, senescence, and oxidative stress. The use of patient-specific and genome-edited human pluripotent stem cell-derived endothelial cells (hPSC-ECs) has shed novel insights into the role of endothelial dysfunction in cardiovascular diseases with strong genetic components such as genetic cardiomyopathies and pulmonary arterial hypertension. However, their utility in studying complex multifactorial diseases such as atherosclerosis, metabolic syndrome and heart failure poses notable challenges. In this review, we provide an overview of the different methods used to generate and characterise hPSC-ECs before comprehensively assessing their effectiveness in cardiovascular disease modelling and high-throughput drug screening. Furthermore, we explore current obstacles that will need to be overcome to unleash the full potential of hPSC-ECs in facilitating patient-specific precision medicine. Addressing these challenges holds great promise in advancing our understanding of intricate cardiovascular diseases and in tailoring personalised therapeutic strategies.

Obstructive sleep apnea hypopnea syndrome and vascular lesions: An update on what we currently know

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is the most prevalent sleep and respiratory disorder. This syndrome can induce severe cardiovascular and cerebrovascular complications, and intermittent hypoxia is a pivotal contributor to this damage. Vascular pathology is closely associated with the impairment of target organs, marking a focal point in current research. Vascular lesions are the fundamental pathophysiological basis of multiorgan ailments and indicate a shared pathogenic mechanism among common cardiovascular and cerebrovascular conditions, suggesting their importance as a public health concern. Increasing evidence shows a strong correlation between OSAHS and vascular lesions. Previous studies predominantly focused on the pathophysiological alterations in OSAHS itself, such as intermittent hypoxia and fragmented sleep, leading to vascular disruptions. This review aims to delve deeper into the vascular lesions affected by OSAHS by examining the microscopic pathophysiological mechanisms involved. Emphasis has been placed on examining how OSAHS induces vascular lesions through disruptions in the endothelial barrier, metabolic dysregulation, cellular phenotype alterations, neuroendocrine irregularities, programmed cell death, vascular inflammation, oxidative stress and epigenetic modifications. This review examines the epidemiology and associated risk factors for OSAHS and vascular diseases and subsequently describes the existing evidence on vascular lesions induced by OSAHS in the cardiovascular, cerebrovascular, retinal, renal and reproductive systems. A detailed account of the current research on the pathophysiological mechanisms mediating vascular lesions caused by OSAHS is provided, culminating in a discussion of research advancements in therapeutic modalities to mitigate OSAHS-related vascular lesions and the implications of these treatment strategies.

Circ_0002331 Interacts with ELAVL1 to Improve ox-LDL-Induced Vascular Endothelial Cell Dysfunction via Regulating CCND2 mRNA Stability

Circular RNAs (circRNAs) have been discovered to serve as vital regulators in atherosclerosis (AS). However, the role and mechanism of circ_0002331 in AS process are still unclear. Human umbilical vein endothelial cells (HUVECs) were treated with ox-LDL to establish an in vitro model for AS. The expression levels of circ_0002331, Cyclin D2 (CCND2) and ELAVL1 were analyzed by quantitative real-time PCR. Cell proliferation, apoptosis, migration, invasion and angiogenesis were assessed by EdU assay, flow cytometry, transwell assay and tube formation assay. The protein levels of CCND2, ELAVL1, and autophagy-related markers were detected using western blot analysis. IL-8 level was analyzed by ELISA. The relationship between ELAVL1 and circ_0002331 or CCND2 was analyzed by RIP assay and RNA pull-down assay. Moreover, FISH assay was used to analyze the co-localization of ELAVL1 and CCND2 in HUVECs. Our data showed that circ_0002331 was obviously downregulated in AS patients and ox-LDL-induced HUVECs. Overexpression of circ_0002331 could promote proliferation, migration, invasion and angiogenesis, while inhibit apoptosis, autophagy and inflammation in ox-LDL-induced HUVECs. Furthermore, CCND2 was positively regulated by circ_0002331, and circ_0002331 could bind with ELAVL1 to promote CCND2 mRNA stability. Besides, CCND2 overexpression suppressed ox-LDL-induced HUVECs dysfunction, and its knockdown also reversed the regulation of circ_0002331 on ox-LDL-induced HUVECs dysfunction. In conclusion, circ_0002331 might be a potential target for AS treatment, which could improve ox-LDL-induced dysfunction of HUVECs via regulating CCND2 by binding with ELAVL1.

Immunomodulatory Activity of Cytokines in Hypertension: A Vascular Perspective

Cytokines play a crucial role in the structure and function of blood vessels in hypertension. Hypertension damages blood vessels by mechanisms linked to shear forces, activation of the renin-angiotensin-aldosterone and sympathetic nervous systems, oxidative stress, and a proinflammatory milieu that lead to the generation of neoantigens and damage-associated molecular patterns, ultimately triggering the release of numerous cytokines. Damage-associated molecular patterns are recognized by PRRs (pattern recognition receptors) and activate inflammatory mechanisms in endothelial cells, smooth muscle cells, perivascular nerves, and perivascular adipose tissue. Activated vascular cells also release cytokines and express factors that attract macrophages, dendritic cells, and lymphocytes to the blood vessels. Activated and differentiated T cells into Th1, Th17, and Th22 in secondary lymphoid organs migrate to the vessels, releasing specific cytokines that further contribute to vascular dysfunction and remodeling. This chronic inflammation alters the profile of endothelial and smooth muscle cells, making them dysfunctional. Here, we provide an overview of how cytokines contribute to hypertension by impacting the vasculature. Furthermore, we explore clinical perspectives about the modulation of cytokines as a potential therapeutic intervention to specifically target hypertension-linked vascular dysfunction.

PCSK9 aggravated carotid artery stenosis in ApoE-/- mice by promoting the expression of tissue factors in endothelial cells via the TLR4/NF-κB pathway

Atherosclerosis, a chronic inflammatory disease, is the most relevant cause of carotid artery stenosis. Vascular endothelial cells (ECs) play a significant role in the development of atherosclerosis. In this chronic inflammatory environment, we aimed to investigate whether PCSK9 could mitigate atherosclerosis progression by reducing tissue factor expression in ECs via in vivo and in vitro assays. In vivo, we investigated the effect of PCSK9 inhibition on preventing atherosclerotic lesion formation in ApoE-/- mice fed a western diet. The results showed that inhibiting PCSK9 could significantly downregulate the protein expression of tissue factor (TF) in ECs to reduce the area of atherosclerotic plaques. In vitro, we incubated human umbilical vein endothelial cells (HUVECs) with lipopolysaccharide (LPS). We found that LPS-induced TF elevation was suppressed by a PCSK9 inhibitor at both the mRNA and protein levels and that the TLR4/NF-κB pathway was also suppressed by a PCSK9 inhibitor. With respect to plasma samples from patients with carotid artery stenosis, we also demonstrated that the expression of TF was positively correlated with that of PCSK9. Thus, in addition to regulating lipid metabolism, the regulation of endothelial cell TF expression through the TLR4/NF-κB pathway may be a potential mechanism of PCSK9 in promoting atherosclerotic carotid stenosis.

Oscillatory shear stress promotes endothelial senescence and atherosclerosis via STING activation

Endothelial dysfunction is an initiating factor in atherosclerosis. Endothelial cells (ECs) are constantly subject to blood flow shear stress, and atherosclerotic plaques tend to occur in aortic bends or bifurcations impaired by low oscillatory shear stress (OSS). However, the mechanism that how OSS affects the initiation and progression of atherosclerosis remains to be explored. Here, we first reported that OSS can promote endothelial dysfunction and atherogenesis in vivo and in vitro by activating STING pathway. Mechanistically, at atherosclerosis-prone areas, OSS caused mitochondria damage in ECs, leading to the leakage of mitochondrial DNA (mtDNA) into the cytoplasm. The cytoplasmic mtDNA was recognized by cGAS to produce cGAMP, activating the STING pathway and leading to endothelial senescence, which resulted in endothelial dysfunction and atherosclerosis. We found that STING was activated in plaques of atherosclerotic patients and in aortic arch ECs of high-fat diet (HFD)-fed ApoeKO mice, as well as in ECs exposed to OSS. STING-specific deficiency in ECs attenuates endothelial senescence and resulted in a significant reduction in aortic arch plaque area in HFD-fed ApoeKO mice. Consistently, specific deficiency or pharmacological inhibition of STING attenuated OSS-induced senescence and endothelial dysfunction. Pharmacological depletion of mtDNA ameliorated OSS-induced senescence and endothelial dysfunction. Taken together, our study linked hemodynamics and endothelial senescence, and revealed a novel mechanism by which OSS leads to endothelial dysfunction. Our study provided new insights into the development of therapeutic strategies for endothelial senescence and atherosclerosis.

Identification of key biomarkers of endothelial dysfunction in hypertension with carotid atherosclerosis based on WGCNA and the LASSO algorithm

Background

Endothelial dysfunction is the early stage of carotid atherosclerosis (CAS) in patients with hypertension. It is worth identifying the potential hub genes of endothelial dysfunction to elucidate pathological mechanism in the progression of the disease.

Method

We obtained gene expression profiles of GSE43292 from the Gene Expression Omnibus (GEO) database. Hub genes associated with CAS were identified through weighted gene correlation network analysis (WGCNA) and least absolute shrinkage and selection operator (LASSO) regression. Subsequently, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to explore potential biological mechanisms and signaling pathways. Finally, in vitro experiments on human umbilical vein endothelial cells (HUVECs) were conducted to validate these hub genes.

Results

The microarray dataset GSE43292 included 32 CAS plaques samples and corresponding macroscopically intact tissues from patients with hypertension. A total of 161 differentially expressed genes were discovered. Through WGCNA analysis, the gray60 module emerged as the most significant module associated with clinical features. The GO and KEGG enrichment analyses of genes in the gray60 module highlighted the substantial involvement of immune response-related signaling pathways. Two key hub genes (CCR1 and NCKAP1L) were pinpointed via LASSO regression. We found a significant increase in the mRNA expression level of the hub genes in oxidized low density lipoprotein (ox-LDL) treated HUVECs.

Conclusions

Our study indicated that the hub genes related to immune responses are involved in the development of CAS. Two hub genes (CCR1 and NCKAP1L) of endothelial dysfunction were identified. These genes may provide a valuable therapeutic target of CAS in patients with hypertension.

Gut microbiota: a superior operator for dietary phytochemicals to improve atherosclerosis

Mounting evidence implicates the gut microbiota as a possible key susceptibility factor for atherosclerosis (AS). The employment of dietary phytochemicals that strive to target the gut microbiota has gained scientific support for treating AS. This study conducted a general overview of the links between the gut microbiota and AS, and summarized available evidence that dietary phytochemicals improve AS via manipulating gut microbiota. Then, the microbial metabolism of several dietary phytochemicals was summarized, along with a discussion on the metabolites formed and the biotransformation pathways involving key gut bacteria and enzymes. This study additionally focused on the anti-atherosclerotic potential of representative metabolites from dietary phytochemicals, and investigated their underlying molecular mechanisms. In summary, microbiota-dependent dietary phytochemical therapy is a promising strategy for AS management, and knowledge of "phytochemical-microbiota-biotransformation" may be a breakthrough in the search for novel anti-atherogenic agents.

Vascular endothelial effects of dibutyl phthalate: In vitro and in vivo evidence

Dibutyl phthalate (DBP) is widely used in many consumer and personal care products. Here, we report vascular endothelial response to DBP in three different exposure scenarios: after short-term exposure (24 h) of human endothelial cells (ECs) EA.hy926 to 10-6, 10-5, and 10-4 M DBP, long-term exposure (12 weeks) of EA.hy926 cells to 10-9, 10-8, and 10-7 M DBP, and exposure of rats (28 and 90 days) to 100, 500, and 5000 mg DBP/kg food. We examined different vascular functions such as migration of ECs, adhesion of ECs to the extracellular matrix, tube formation, the morphology of rat aorta, as well as several signaling pathways involved in controlling endothelial function. Short-term in vitro exposure to DBP increased migration of ECs through G protein-coupled estrogen receptor, extracellular signal-regulated kinase 1/2, and nitric oxide (NO) signaling and decreased adhesion to gelatin. Long-term in vitro exposure to DBP transiently increased EC migration and had a bidirectional effect on EC adhesion to gelatin and tube formation. These effects were accompanied by a sustained increase in NO production and endothelial NO synthase (eNOS) and Akt activity. In vivo, exposure to DBP for 90 days decreased the aortic wall-to-lumen ratio and increased eNOS and Akt phosphorylation in ECs of rat aorta. This comparative investigation has shown that exposure to DBP may affect vascular function by altering EC migration, adhesion to gelatin, and tube formation after short- and long-term in vitro exposure and by decreasing the aortic wall-to-lumen ratio in vivo. The eNOS-NO and Akt signaling could be important in mediating the effects of DBP in long-term exposure scenarios.

Potential protective role of let-7d-5p in atherosclerosis progression reducing the inflammatory pathway regulated by NF-κB and vascular smooth muscle cells proliferation

The prevalence of cardiovascular diseases (CVDs) is increasing in the last decades, even is the main cause of death in first world countries being atherosclerosis one of the principal triggers. Therefore, there is an urgent need to decipher the underlying mechanisms involved in atherosclerosis progression. In this respect, microRNAs dysregulation is frequently involved in the progression of multiple diseases including CVDs. Our aim was to demonstrate that let-7d-5p unbalance could contribute to the pathophysiology of atherosclerosis and serve as a potential diagnostic biomarker. We evaluated let-7d-5p levels in vascular biopsies and exosome-enriched extracellular vesicles (EVs) from patients with carotid atherosclerosis and healthy donors. Moreover, we overexpressed let-7d-5p in vitro in vascular smooth muscle cells (VSMCs) to decipher the targets and the underlying mechanisms regulated by let-7d-5p in atherosclerosis. Our results demonstrate that let-7d-5p was significantly upregulated in carotid plaques from overweight patients with carotid atherosclerosis. Moreover, in EVs isolated from plasma, we found that let-7d-5p levels were increased in carotid atherosclerosis patients compared to control subjects specially in overweight patients. Receiver Operating Characteristic (ROC) analyses confirmed its utility as a diagnostic biomarker for atherosclerosis. In VSMCs, we demonstrated that increased let-7d-5p levels impairs cell proliferation and could serve as a protective mechanism against inflammation by impairing NF-κB pathway without affecting insulin resistance. In summary, our results highlight the role of let-7d-5p as a potential therapeutic target for atherosclerosis since its overexpression induce a decrease in inflammation and VSMCs proliferation, and also, as a novel non-invasive diagnostic biomarker for atherosclerosis in overweight patients.

Autoimmune diseases and atherosclerotic cardiovascular disease

Autoimmune diseases are associated with a dramatically increased risk of atherosclerotic cardiovascular disease and its clinical manifestations. The increased risk is consistent with the notion that atherogenesis is modulated by both protective and disease-promoting immune mechanisms. Notably, traditional cardiovascular risk factors such as dyslipidaemia and hypertension alone do not explain the increased risk of cardiovascular disease associated with autoimmune diseases. Several mechanisms have been implicated in mediating the autoimmunity-associated cardiovascular risk, either directly or by modulating the effect of other risk factors in a complex interplay. Aberrant leukocyte function and pro-inflammatory cytokines are central to both disease entities, resulting in vascular dysfunction, impaired resolution of inflammation and promotion of chronic inflammation. Similarly, loss of tolerance to self-antigens and the generation of autoantibodies are key features of autoimmunity but are also implicated in the maladaptive inflammatory response during atherosclerotic cardiovascular disease. Therefore, immunomodulatory therapies are potential efficacious interventions to directly reduce the risk of cardiovascular disease, and biomarkers of autoimmune disease activity could be relevant tools to stratify patients with autoimmunity according to their cardiovascular risk. In this Review, we discuss the pathophysiological aspects of the increased cardiovascular risk associated with autoimmunity and highlight the many open questions that need to be answered to develop novel therapies that specifically address this unmet clinical need.

The crosstalk between neuropilin-1 and tumor necrosis factor-α in endothelial cells

Tumor necrosis factor-α (TNFα) is a master cytokine which induces expression of chemokines and adhesion molecules, such as intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), in endothelial cells to initiate the vascular inflammatory response. In this study, we identified neuropilin-1 (NRP1), a co-receptor of several structurally diverse ligands, as a modulator of TNFα-induced inflammatory response of endothelial cells. NRP1 shRNA expression suppressed TNFα-stimulated leukocyte adhesion and expression of ICAM-1 and VCAM-1 in human umbilical vein endothelial cells (HUVECs). Likewise, it reduced TNFα-induced phosphorylation of MAPK p38 but did not significantly affect other TNF-induced signaling pathways, such as the classical NFκB and the AKT pathway. Immunofluorescent staining demonstrated co-localization of NRP1 with the two receptors of TNF, TNFR1 and TNFR2. Co-immunoprecipitation further confirmed that NRP1 was in the same protein complex or membrane compartment as TNFR1 and TNFR2, respectively. Modulation of NRP1 expression, however, neither affected TNFR levels in the cell membrane nor the receptor binding affinities of TNFα. Although a direct interface between NRP1 and TNFα/TNFR1 appeared possible from a protein docking model, a direct interaction was not supported by binding assays in cell-free microplates and cultured cells. Furthermore, TNFα was shown to downregulate NRP1 in a time-dependent manner through TNFR1-NFκB pathway in HUVECs. Taken together, our study reveals a novel reciprocal crosstalk between NRP1 and TNFα in vascular endothelial cells.

Engineering microvascular networks using a KLF2 reporter to probe flow-dependent endothelial cell function

Shear stress generated by the flow of blood in the vasculature is a potent regulator of endothelial cell function and vascular structure. While vascular responses to flow are complex and context-dependent, endothelial cell signaling in response to shear stress induced by laminar flows is coordinated by the transcription factor KLF2. The flow-dependent expression of KLF2 in endothelial cells is associated with a quiescent, anti-inflammatory phenotype and has been well characterized in two-dimensional systems but has not been studied in three-dimensional in vitro systems. Here we develop engineered microvascular networks (MVNs) that incorporate a KLF2-based endothelial cell flow sensor within a microfluidic chip, apply continuous flow using an attached microfluidic pump, and study the effects of this flow on vascular structure and function. We found that application of flow to MVNs for 48 h resulted in increased expression of the KLF2 reporter, larger vessel diameters, and decreased vascular branching and resistance. Notably, vessel diameters after the application of flow were independent of initial MVN morphologies. Finally, we found that MVNs exposed to flow have improved vascular barrier function and decreased platelet adhesion. MVNs with KLF2-based flow sensors represent a novel, powerful tool for evaluating the structural and functional effects of flow on engineered three-dimensional vascular systems.

The association of microvascular disease and endothelial dysfunction with vertebral trabecular bone mineral density : The MESA study

Retinopathy and albuminuria are associated with hip fracture risk. We investigated whether these disorders and endothelial dysfunction (which underlies microvascular diseases) were associated with low trabecular bone density. No significant associations were found, suggesting that microvascular diseases are not related to fracture risk through low trabecular bone density.

PURPOSE

Microvascular diseases of the eye, kidney, and brain are associated with endothelial dysfunction and increased hip fracture risk. To explore the basis for higher hip fracture risk, we comprehensively examined whether markers of microvascular disease and/or endothelial dysfunction are related to trabecular bone mineral density (BMD), a proximate risk factor for osteoporotic fractures.

METHODS

Among 6814 participants in the Multi-Ethnic Study of Atherosclerosis study (MESA), we derived thoracic vertebral trabecular BMD from computed tomography of the chest and measured urine albumin to creatinine ratios (UACR), retinal arteriolar and venular widths, flow mediated dilation (FMD) of the brachial artery after 5 min of ischemia; and levels of five soluble endothelial adhesion markers (ICAM-1, VCAM-1, L-selectin, P-selectin, and E-selectin). Linear regression models were used to examine the association of trabecular BMD with markers of microvascular disease and with markers of endothelial dysfunction.

RESULTS

We observed no significant associations of UACR, retinal arteriolar or venular widths, or FMD with BMD. We also observed no statistically significant association of spine trabecular BMD with levels of endothelial adhesion markers. Men and women had largely similar results.

CONCLUSION

We conclude that there is little evidence to connect thoracic spine trabecular BMD to microvascular disorders or to endothelial dysfunction among multi-ethnic middle-aged and older adults. Other factors beyond trabecular BMD (e.g., bone quality or predisposition to falling) may be responsible for the associations of microvascular disease with osteoporotic fractures.

Oxidative stress and vascular dysfunction: Potential therapeutic targets and therapies in peripheral artery disease

Peripheral artery disease (PAD) is the manifestation of atherosclerosis characterized by the accumulation of plaques in the arteries of the lower limbs. Interestingly, growing evidence suggests that the pathology of PAD is multifaceted and encompasses both vascular and skeletal muscle dysfunctions, which contributes to blunted physical capabilities and diminished quality of life. Importantly, it has been suggested that many of these pathological impairments may stem from blunted reduction-oxidation (redox) handling. Of note, in those with PAD, excessive production of reactive oxygen species (ROS) outweighs antioxidant capabilities resulting in oxidative damage, which may have systemic consequences. It has been suggested that antioxidant supplementation may be able to assist in handling ROS. However, the activation of various ROS production sites makes it difficult to determine the efficacy of these antioxidant supplements. Therefore, this review focuses on the common cellular mechanisms that facilitate ROS production and discusses how excessive ROS may impair vascular and skeletal muscle function in PAD. Furthermore, we provide insight for current and potential antioxidant therapies, specifically highlighting activation of the Kelch-like ECH-associated protein 1 (Keap1) - Nuclear Factor Erythroid 2-related factor 2 (Nrf2) pathway as a potential pharmacological therapy to combat ROS accumulation and aid in vascular function, and physical performance in patients with PAD. Altogether, this review provides a better understanding of excessive ROS in the pathophysiology of PAD and enhances our perception of potential therapeutic targets that may improve vascular function, skeletal muscle function, walking capacity, and quality of life in patients with PAD.

Resolving neutrophils through genetic deletion of TRAM attenuate atherosclerosis pathogenesis

Systemic neutrophil dysregulation contributes to atherosclerosis pathogenesis, and restoring neutrophil homeostasis may be beneficial for treating atherosclerosis. Herein, we report that a homeostatic resolving subset of neutrophils exists in mice and humans characterized by the low expression of TRAM, correlated with reduced expression of inflammatory mediators (leukotriene B4 [LTB4] and elastase) and elevated expression of anti-inflammatory resolving mediators (resolvin D1 [RvD1] and CD200R). TRAM-deficient neutrophils can potently improve vascular integrity and suppress atherosclerosis pathogenesis when adoptively transfused into recipient atherosclerotic animals. Mechanistically, we show that TRAM deficiency correlates with reduced expression of 5-lipoxygenase (LOX5) activating protein (LOX5AP), dislodges nuclear localization of LOX5, and switches the lipid mediator secretion from pro-inflammatory LTB4 to pro-resolving RvD1. TRAM also serves as a stress sensor of oxidized low-density lipoprotein (oxLDL) and/or free cholesterol and triggers inflammatory signaling processes that facilitate elastase release. Together, our study defines a unique neutrophil population characterized by reduced TRAM, capable of homeostatic resolution and treatment of atherosclerosis.

Early Injury Landscape in Vein Harvest by Single-Cell and Spatial Transcriptomics

BACKGROUND

Vein graft failure following cardiovascular bypass surgery results in significant patient morbidity and cost to the healthcare system. Vein graft injury can occur during autogenous vein harvest and preparation, as well as after implantation into the arterial system, leading to the development of intimal hyperplasia, vein graft stenosis, and, ultimately, bypass graft failure. Although previous studies have identified maladaptive pathways that occur shortly after implantation, the specific signaling pathways that occur during vein graft preparation are not well defined and may result in a cumulative impact on vein graft failure. We, therefore, aimed to elucidate the response of the vein conduit wall during harvest and following implantation, probing the key maladaptive pathways driving graft failure with the overarching goal of identifying therapeutic targets for biologic intervention to minimize these natural responses to surgical vein graft injury.

METHODS

Employing a novel approach to investigating vascular pathologies, we harnessed both single-nuclei RNA-sequencing and spatial transcriptomics analyses to profile the genomic effects of vein grafts after harvest and distension, then compared these findings to vein grafts obtained 24 hours after carotid-carotid vein bypass implantation in a canine model (n=4).

RESULTS

Spatial transcriptomic analysis of canine cephalic vein after initial conduit harvest and distention revealed significant enrichment of pathways (P<0.05) involved in the activation of endothelial cells (ECs), fibroblasts, and vascular smooth muscle cells, namely pathways responsible for cellular proliferation and migration and platelet activation across the intimal and medial layers, cytokine signaling within the adventitial layer, and ECM (extracellular matrix) remodeling throughout the vein wall. Subsequent single-nuclei RNA-sequencing analysis supported these findings and further unveiled distinct EC and fibroblast subpopulations with significant upregulation (P<0.05) of markers related to endothelial injury response and cellular activation of ECs, fibroblasts, and vascular smooth muscle cells. Similarly, in vein grafts obtained 24 hours after arterial bypass, there was an increase in myeloid cell, protomyofibroblast, injury response EC, and mesenchymal-transitioning EC subpopulations with a concomitant decrease in homeostatic ECs and fibroblasts. Among these markers were genes previously implicated in vein graft injury, including VCAN, FBN1, and VEGFC, in addition to novel genes of interest, such as GLIS3 and EPHA3. These genes were further noted to be driving the expression of genes implicated in vascular remodeling and graft failure, such as IL-6, TGFBR1, SMAD4, and ADAMTS9. By integrating the spatial transcriptomics and single-nuclei RNA-sequencing data sets, we highlighted the spatial architecture of the vein graft following distension, wherein activated and mesenchymal-transitioning ECs, myeloid cells, and fibroblasts were notably enriched in the intima and media of distended veins. Finally, intercellular communication network analysis unveiled the critical roles of activated ECs, mesenchymal-transitioning ECs, protomyofibroblasts, and vascular smooth muscle cells in upregulating signaling pathways associated with cellular proliferation (MDK [midkine], PDGF [platelet-derived growth factor], VEGF [vascular endothelial growth factor]), transdifferentiation (Notch), migration (ephrin, semaphorin), ECM remodeling (collagen, laminin, fibronectin), and inflammation (thrombospondin), following distension.

CONCLUSIONS

Vein conduit harvest and distension elicit a prompt genomic response facilitated by distinct cellular subpopulations heterogeneously distributed throughout the vein wall. This response was found to be further exacerbated following vein graft implantation, resulting in a cascade of maladaptive gene regulatory networks. Together, these results suggest that distension initiates the upregulation of pathological pathways that may ultimately contribute to bypass graft failure and presents potential early targets warranting investigation for targeted therapies. This work highlights the first applications of single-nuclei and spatial transcriptomic analyses to investigate venous pathologies, underscoring the utility of these methodologies and providing a foundation for future investigations.

Lactate and lactylation in cardiovascular diseases: current progress and future perspectives

Cardiovascular diseases (CVDs) are often linked to structural and functional impairments, such as heart defects and circulatory dysfunction, leading to compromised peripheral perfusion and heightened morbidity risks. Metabolic remodeling, particularly in the context of cardiac fibrosis and inflammation, is increasingly recognized as a pivotal factor in the pathogenesis of CVDs. Metabolic syndromes further predispose individuals to these conditions, underscoring the need to elucidate the metabolic underpinnings of CVDs. Lactate, a byproduct of glycolysis, is now recognized as a key molecule that connects cellular metabolism with the regulation of cellular activity. The transport of lactate between different cells is essential for metabolic homeostasis and signal transduction. Disruptions to lactate dynamics are implicated in various CVDs. Furthermore, lactylation, a novel post-translational modification, has been identified in cardiac cells, where it influences protein function and gene expression, thereby playing a significant role in CVD pathogenesis. In this review, we summarized recent advancements in understanding the role of lactate and lactylation in CVDs, offering fresh insights that could guide future research directions and therapeutic interventions. The potential of lactate metabolism and lactylation as innovative therapeutic targets for CVD is a promising avenue for exploration.

Exploring global research trends in Chinese medicine for atherosclerosis: a bibliometric study 2012-2023

Background

While Traditional Chinese Medicine (TCM) boasts an extensive historical lineage and abundant clinical expertise in addressing atherosclerosis, this field is yet to be penetrated adequately by bibliometric studies. This study is envisaged to evaluate the contemporary scenario of TCM in conjunction with atherosclerosis over the preceding decade while also identifying forthcoming research trends and emerging topics via the lens of bibliometric analysis.

Methods

Literature pertaining to TCM and atherosclerosis, circulated between January 1, 2012 and November 14, 2023, was garnered for the purpose of this research. The examination embraced annual publications, primary countries/regions, engaged institutions and authors, scholarly journals, references, and keywords, utilizing analytical tools like Bibliometrix, CiteSpace, ScimagoGraphica, and VOSviewer present in the R package.

Result

This field boasts a total of 1,623 scholarly articles, the majority of which have been contributed by China in this field, with significant contributions stemming from the China Academy of Traditional Chinese Medicine and the Beijing University of Traditional Chinese Medicine. Moreover, this field has received financial support from both the National Natural Science Foundation of China and the National Key Basic Research Development Program. Wang Yong tops the list in terms of publication count, while Xu Hao's articles take the lead for the total number of citations, positioning them at the core of the authors' collaborative network. The Journal of Ethnopharmacology leads with the most publications and boasts the greatest total number of citations. Principal research foci within the intersection of Chinese Medicine and Atherosclerosis encompass disease characteristics and pathogenic mechanisms, theoretical underpinnings and syndrome-specific treatments in Chinese medicine, potentialities of herbal interventions, and modulation exerted by Chinese medicines on gut microbiota.

Conclusion

This analysis offers a sweeping survey of the contemporary condition, principal foci, and progressive trends in worldwide research related to Traditional Chinese Medicine (TCM) and atherosclerosis. It further delves into an in-depth dissection of prominent countries, research institutions, and scholars that have made noteworthy strides in this discipline. Additionally, the report analyzes the most cited articles, research developments, and hotspots in the field, providing a reference for future research directions for clinical researchers and practitioners.

Anti-atherogenic mechanism of ethanol extract of Christia vespertilionis (L.f.) Bakh. F. Leaves in vitro

BACKGROUND

Vascular inflammation is the key event in early atherogenesis. Pro-inflammatory endothelial cells induce monocyte recruitment into the sub-endothelial layer of the artery. This requires endothelial expression of adhesion molecules namely intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), alongside chemokines production. Christia vespertilionis (L.f.) Bakh.f. (CV) possesses anti-inflammatory property. However, its potential anti-atherogenic effect in the context of vascular inflammation has yet to be explored.

PURPOSE

To evaluate the anti-atherogenic mechanism of 80% ethanol extract of CV leaves on tumor necrosis factor-α (TNF-α)-activated human umbilical vein endothelial cells (HUVECs).

METHODS

Qualitative analysis of the CV extract was carried out by using liquid chromatography with tandem mass spectrometry (LC-MS/MS). The cell viability of HUVECs treated with CV extract was determined by MTT assay. The effect of CV extract on monocyte adhesion was determined by monocyte-endothelial adhesion assay. Protein expressions of ICAM-1, VCAM-1 and nuclear factor-kappa B (NF-κB) signaling pathway were determined by western blot while production of monocyte chemoattractant protein-1 (MCP-1) was determined by ELISA.

RESULTS

LC-MS/MS analysis showed that CV extract composed of five main compounds, including schaftoside, orientin, isovitexin, 6-caffeoyl-D-glucose, and 3,3'-di-O-methyl ellagic acid. Treatment of CV extract at a concentration range from 5 to 60 µg/mL for 24 h maintained HUVECs viability above 90 %, therefore concentrations of 20, 40 and 60 μg/mL were selected for the subsequent experiments. All concentrations of CV extract showed a significant inhibitory effect on monocyte adhesion to TNF-α-activated HUVECs (p < 0.05). In addition, the protein expressions of ICAM-1 and VCAM-1 were significantly attenuated by CV in a concentration dependent manner (p < 0.001). At all tested concentrations, CV extract also exhibited significant inhibition on the production of MCP-1 (p < 0.05). Moreover, CV extract significantly inhibited TNF-α-induced phosphorylation of inhibitor of nuclear factor-κB kinase alpha/beta (IKKα/β), inhibitor kappa B-alpha (IκBα), NF-κB and nuclear translocation of NF-κB (p < 0.05).

CONCLUSION

CV extract inhibited monocyte adhesion to endothelial cells by suppressing protein expressions of cell adhesion molecules and production of chemokines through downregulation of NF-κB signaling pathway. Thus, CV has the potential to be developed as an anti-atherogenic agent for early treatment of atherosclerosis.

Insights from Murine Studies on the Site Specificity of Atherosclerosis

Atherosclerosis is an inflammatory reaction that develops at specific regions within the artery wall and at specific sites of the arterial tree over a varying time frame in response to a variety of risk factors. The mechanisms that account for the interaction of systemic factors and atherosclerosis-susceptible regions of the arterial tree to mediate this site-specific development of atherosclerosis are not clear. The dynamics of blood flow has a major influence on where in the arterial tree atherosclerosis develops, priming the site for interactions with atherosclerotic risk factors and inducing cellular and molecular participants in atherogenesis. But how this accounts for lesion development at various locations along the vascular tree across differing time frames still requires additional study. Currently, murine models are favored for the experimental study of atherogenesis and provide the most insight into the mechanisms that may contribute to the development of atherosclerosis. Based largely on these studies, in this review, we discuss the role of hemodynamic shear stress, SR-B1, and other factors that may contribute to the site-specific development of atherosclerosis.

Effect of Exercise Prior to Sedentary Behavior on Vascular Health Parameters: A Systematic Review and Meta-Analysis of Crossover Trials

BACKGROUND

Sedentary behavior has been shown to negatively affect parameters of endothelial function and central hemodynamics, both of which are closely associated with vascular health. Exercise prior to sedentary behavior has demonstrated potential as a preventive strategy to mitigate these detrimental effects. To evaluate the impact of exercise prior to sedentary behavior on vascular health parameters in the adult population, a systematic review and meta-analysis were conducted, synthesizing the available body of knowledge.

METHODS

A literature search was carried out in 6 databases. For each outcome, standard error and mean difference or standardized mean difference were calculated, as appropriate. An analysis was performed using a random effects model with a 95% confidence interval, using the inverse variance statistical method. Risk of bias assessment was performed using ROB2 and considerations for crossover trials. The quality of evidence was assessed using the GRADE system.

RESULTS

Exercise performed prior to prolonged sedentary behavior resulted in increased flow-mediated vasodilation at the first and third hours of sedentary time, compared with the control condition of sedentary behavior without prior exercise [MD: 1.51% (95% CI: 0.57 to 2.45) and MD: 1.36% (95% CI: 0.56 to 2.16), respectively]. Moreover, prior exercise led to increased shear rate at the first and third hours of sedentary time [MD: 7.70 s^-1 (95% CI: 0.79 to 14.61) and MD: 5.21 s^-1 (95% CI: 1.77 to 8.43), respectively]. Furthermore, it increased blood flow at the third hour [SMD: 0.40 (95%CI: 0.07 to 0.72)], compared with the control condition of prolonged sedentary behavior without prior exercise. Regarding hemodynamic parameters, exercise prior to prolonged sedentary behavior decreased mean arterial pressure during the first and third hours of sedentary behavior [MD: -1.94 mmHg (95% CI: -2.77 to -1.11) and MD: -1.90 mmHg (95% CI: -3.27 to -0.53), respectively], and an increase in heart rate during the first hour [MD: 4.38 beats per minute (95%CI: 2.78 to 5.98)] compared with the control condition of prolonged sedentary behavior without prior exercise.

CONCLUSIONS

The findings of this research suggest that prior exercise may prevent the impairment of vascular health parameters caused by sedentary behavior. However, the quality of the evidence was estimated as moderate. Therefore, further experimental studies and high-quality clinical trials are needed in this field to strengthen the results and conclusions drawn.

PROSPERO REGISTRATION NUMBER

CRD42023393686.

M1/M2 macrophage-targeted nanotechnology and PROTAC for the treatment of atherosclerosis

Macrophages play key roles in atherosclerosis progression, and an imbalance in M1/M2 macrophages leads to unstable plaques; therefore, M1/M2 macrophage polarization-targeted treatments may serve as a new approach in the treatment of atherosclerosis. At present, there is little research on M1/M2 macrophage polarization-targeted nanotechnology. Proteolysis-targeting chimera (PROTAC) technology, a targeted protein degradation technology, mediates the degradation of target proteins and has been widely promoted in preclinical and clinical applications as a novel therapeutic modality. This review summarizes the recent studies on M1/M2 macrophage polarization-targeted nanotechnology, focusing on the mechanism and advantages of PROTACs in M1/M2 macrophage polarization as a new approach for the treatment of atherosclerosis.

SphK1 deficiency ameliorates the development of atherosclerosis by inhibiting the S1P/S1PR3/Rhoa/ROCK pathway

BACKGROUND AND AIMS

S1P is an important factor regulating the function of the vascular endothelial barrier. SphK1 is an important limiting enzyme for the synthesis of S1P. However, the role of the SphK1/S1P-mediated vascular endothelial barrier function in atherosclerosis has not been fully revealed. This study explored the roles and mechanisms of SphK1 on atherosclerosis in vivo and in vitro.

METHODS

In vivo, ApoE-/- and SphK1-/-ApoE-/- mice were fed a high-fat diet to induce atherosclerosis. In vitro, ox-LDL induced HUVECs to establish a cell model. Aortic histological changes were measured by H&E staining, Oil Red O staining, EVG staining, Sirius scarlet staining, immunofluorescence, and Evans Blue Assay. Western blotting was performed to explore the specific mechanism.

RESULTS

We validated that deficiency of SphK1 resulted in a marked amelioration of atherosclerosis, as indicated by the decreased lipid accumulation, inflammatory factors, oxidative stress, aortic plaque area, inflammatory factor infiltration, VCAM-1 expression, and vascular endothelial permeability. Moreover, deficiency of SphK1 downregulated the expression of aortic S1PR3, Rhoa, ROCK, and F-actin. The results of administration with the SphK1 inhibitor PF-543 and the S1PR3 inhibitor VPC23019 in vitro further confirmed the conclusion that deficiency of SphK1 reduced S1P level and S1PR3 protein expression, inhibited Rhoa/ROCK signaling pathway, regulated protein expression of F-actin, improved vascular endothelial dysfunction and permeability, and exerted anti-atherosclerotic effects.

CONCLUSIONS

This study revealed that deficiency of SphK1 relieved vascular endothelial barrier function in atherosclerosis mice via SphK1/S1P/S1PR signaling pathway.

Chronic Obstructive Pulmonary Disease Exacerbations Increase the Risk of Subsequent Cardiovascular Events: A Longitudinal Analysis of the COPDGene Study

BACKGROUND

Cardiovascular disease (CVD) is the most important comorbidity in patients with chronic obstructive pulmonary disease (COPD). COPD exacerbations not only contribute to COPD progression but may also elevate the risk of CVD. This study aimed to determine whether COPD exacerbations increase the risk of subsequent CVD events using up to 15 years of prospective longitudinal follow-up data from the COPDGene (Genetic Epidemiology of Chronic Obstructive Pulmonary Disease) study.

METHODS AND RESULTS

The COPDGene study is a large, multicenter, longitudinal investigation of COPD, including subjects at enrollment aged 45 to 80 years with a minimum of 10 pack-years of smoking history. Cox proportional hazards models and Kaplan-Meier survival curves were used to assess the risk of a composite end point of CVD based on the COPD exacerbation rate. Frequent exacerbators exhibited a higher cumulative incidence of composite CVD end points than infrequent exacerbators, irrespective of the presence of CVD at baseline. After adjusting for covariates, frequent exacerbators still maintained higher hazard ratios (HRs) than the infrequent exacerbator group (without CVD: HR, 1.81 [95% CI, 1.47-2.22]; with CVD: HR, 1.92 [95% CI, 1.51-2.44]). This observation remained consistently significant in moderate to severe COPD subjects and the preserved ratio impaired spirometry population. In the mild COPD population, frequent exacerbators showed a trend toward more CVD events.

CONCLUSIONS

COPD exacerbations are associated with an increased risk of subsequent cardiovascular events in subjects with and without preexisting CVD. Patients with COPD experiencing frequent exacerbations may necessitate careful monitoring and additional management for subsequent potential CVD.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT00608764.

Endothelial-to-Mesenchymal Transition in Cardiovascular Pathophysiology

Under different pathophysiological conditions, endothelial cells lose endothelial phenotype and gain mesenchymal cell-like phenotype via a process known as endothelial-to-mesenchymal transition (EndMT). At the molecular level, endothelial cells lose the expression of endothelial cell-specific markers such as CD31/platelet-endothelial cell adhesion molecule, von Willebrand factor, and vascular-endothelial cadherin and gain the expression of mesenchymal cell markers such as α-smooth muscle actin, N-cadherin, vimentin, fibroblast specific protein-1, and collagens. EndMT is induced by numerous different pathways triggered and modulated by multiple different and often redundant mechanisms in a context-dependent manner depending on the pathophysiological status of the cell. EndMT plays an essential role in embryonic development, particularly in atrioventricular valve development; however, EndMT is also implicated in the pathogenesis of several genetically determined and acquired diseases, including malignant, cardiovascular, inflammatory, and fibrotic disorders. Among cardiovascular diseases, aberrant EndMT is reported in atherosclerosis, pulmonary hypertension, valvular disease, fibroelastosis, and cardiac fibrosis. Accordingly, understanding the mechanisms behind the cause and/or effect of EndMT to eventually target EndMT appears to be a promising strategy for treating aberrant EndMT-associated diseases. However, this approach is limited by a lack of precise functional and molecular pathways, causes and/or effects, and a lack of robust animal models and human data about EndMT in different diseases. Here, we review different mechanisms in EndMT and the role of EndMT in various cardiovascular diseases.

Exploring the relationship between hemodynamics and the immune microenvironment in carotid atherosclerosis: Insights from CFD and CyTOF technologies

Carotid atherosclerosis is a major cause of stroke. Hemodynamic forces, such as shear stress and oscillatory shear, play an important role in the initiation and progression of atherosclerosis. The alteration of the immune microenvironment is the fundamental pathological mechanism by which diverse external environmental factors impact the formation and progression of plaques. However, Current research on the relationship between hemodynamics and immunity in atherosclerosis still lack of comprehensive understanding. In this study, we combined computational fluid dynamics (CFD) and Mass cytometry (CyTOF) technologies to explore the changes in the immune microenvironment within plaques under different hemodynamic conditions. Our results indicated that neutrophils were enriched in adverse flow environments. M2-like CD163+CD86+ macrophages were predominantly enriched in high WSS and low OSI environments, while CD163-CD14+ macrophages were enriched in low WSS and high OSI environments. Functional analysis further revealed T cell pro-inflammatory activation and dysregulation in modulation, along with an imbalance in M1-like/M2-like macrophages, suggesting their potential involvement in the progression of atherosclerotic lesions mediated by adverse flow patterns. Our study elucidated the potential mechanisms by which hemodynamics regulated the immune microenvironment within plaques, providing intervention targets for future precision therapies.

Linking peripheral atherosclerosis to blood-brain barrier disruption: elucidating its role as a manifestation of cerebral small vessel disease in vascular cognitive impairment

Aging plays a pivotal role in the pathogenesis of cerebral small vessel disease (CSVD), contributing to the onset and progression of vascular cognitive impairment and dementia (VCID). In older adults, CSVD often leads to significant pathological outcomes, including blood-brain barrier (BBB) disruption, which in turn triggers neuroinflammation and white matter damage. This damage is frequently observed as white matter hyperintensities (WMHs) in neuroimaging studies. There is mounting evidence that older adults with atherosclerotic vascular diseases, such as peripheral artery disease, ischemic heart disease, and carotid artery stenosis, face a heightened risk of developing CSVD and VCID. This review explores the complex relationship between peripheral atherosclerosis, the pathogenesis of CSVD, and BBB disruption. It explores the continuum of vascular aging, emphasizing the shared pathomechanisms that underlie atherosclerosis in large arteries and BBB disruption in the cerebral microcirculation, exacerbating both CSVD and VCID. By reviewing current evidence, this paper discusses the impact of endothelial dysfunction, cellular senescence, inflammation, and oxidative stress on vascular and neurovascular health. This review aims to enhance understanding of these complex interactions and advocate for integrated approaches to manage vascular health, thereby mitigating the risk and progression of CSVD and VCID.

Electronic cigarettes and cardiovascular disease: epidemiological and biological links

Electronic cigarettes (e-cigarettes), as alternative nicotine delivery methods, has rapidly increased among youth and adults in recent years. However, cardiovascular safety is an important consideration regarding e-cigarettes usage. e-cigarette emissions, including nicotine, propylene glycol, flavorings, nitrosamine, and metals, might have adverse effects on cardiovascular health. A large body of epidemiological evidence has indicated that e-cigarettes are considered an independent risk factor for increased rates of cardiovascular disease occurrence and death. The incidence and mortality of various types of cardiovascular disease, such as cardiac arrhythmia, hypertension, acute coronary syndromes, and heart failure, have a modest growth in vapers (users of e-cigarettes). Although the underlying biological mechanisms have not been fully understood, studies have validated that oxidative stress, inflammation, endothelial dysfunction, atherosclerosis, hemodynamic effects, and platelet function play important roles in which e-cigarettes work in the human body. This minireview consolidates and discusses the epidemiological and biological links between e-cigarettes and various types of cardiovascular disease.

Validation of Signal Intensity Gradient from TOF-MRA for Wall Shear Stress by Phase-Contrast MR

To validate the correlation between the signal intensity gradient (SIG) from time-of-flight magnetic resonance angiography (TOF-MRA) and wall shear stress (WSS) determined by phase contrast magnetic resonance (PC-MR), we conducted both experimental and human studies. In the experimental study, we measured WSS in four tubes of different sizes with variable flow rates using PC-MR and TOF-MRA. The flow rates of water in the experimental study ranged from 0.06 to 12.75 mL/s, resulting in PC-WSS values between 0.1 and 1.6 dyne/cm2. The correlation between PC-WSS and SIG was statistically significant, showing a coefficient of 0.86 (P < 0.001, R2 = 0.75). The line fit provided the conversion equation as Y = 1.6287X - 1.1563 (Y = PC-WSS, X = SIG). For the human study, 28 subjects underwent TOF-MRA and PC-MR examinations of carotid and vertebral arteries. Arterial PC-WSS and SIG were determined in the same segment for each subject. The arterial PC-WSS ranged from 1.9 to 21.0 dyne/cm2. Both carotid and vertebral arteries showed significant correlations between PC-WSS and SIG, with coefficients of 0.85, 0.86, 0.91, and 0.81 in the right and left carotid and vertebral arteries, respectively. Our results show that SIG from TOF-MRA and SIG-WSS derived from the conversion equation provide concurrent in vivo hemodynamic information on arterial shear stress. This study was registered on ClinicalTrials.gov with the identifier NCT04585971 on October 14, 2020.

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

BACKGROUND

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Focus of endothelial glycocalyx dysfunction in ischemic stroke and Alzheimer's disease: Possible intervention strategies

The integrity of the endothelial glycocalyx (eGCX), a mixture of carbohydrates attached to proteins expressed on the surface of blood vessel endothelial cells (EC), is critical for the maintenance of homeostasis of the cardiovascular system and all systems of the human body, the endothelium being the critical component of the stroma of all tissues. Consequently, dysfunction of eGCX results in a dysfunctional cardiovascular wall and severe downstream cardiovascular events, which contribute to the onset of cardio- and cerebrovascular diseases and neurodegenerative disorders, as well as other age-related diseases (ARDs). The key role of eGCX dysfunction in the onset of ARDs is examined here, with a focus on the most prevalent neurological diseases: ischemic stroke and Alzheimer's disease. Furthermore, the advantages and limitations of some treatment strategies for anti-eGCX dysfunction are described, ranging from experimental drug therapies, which need to be better tested and explored not only in animal models but also in humans, as well as reprogramming, the use of nutraceuticals, which are emerging as regenerative and new approaches. The promotion of these strategies is essential to keep eGCX and endothelium healthy, as is the development of intravital (e.g., intravascular) tools to estimate eGCX health status and treatment efficacy, which could lead to advanced solutions to address ARDs.

WY-14643, a novel antiplatelet and antithrombotic agent targeting the GPIbα receptor

BACKGROUND AND PURPOSE

Hypolipidemia and platelet activation play key roles in atherosclerotic diseases. Pirinixic acid (WY-14643) was originally developed as a lipid-lowering drug. Here we focused on its antiplatelet and antithrombotic abilities and the underlying mechanism.

EXPERIMENTAL APPROACH

The effects of WY-14643 on platelet aggregation was measured using a lumi-aggregometer. Clot retraction and spreading on fibrinogen were also assayed. PPARα-/- platelets were used to identify the target of WY-14643. The interaction between WY-14643 and glycoprotein Ibα (GPIbα) was detected using cellular thermal shift assay (CETSA), surface plasmon resonance (SPR) spectroscopy and molecular docking. GPIbα downstream signaling was examined by Western blot. The antithrombotic effect was investigated using mouse mesenteric arteriole thrombosis model. Mouse tail bleeding model was used to study its effect on bleeding side effects.

KEY RESULTS

WY-14643 concentration-dependently inhibits human washed platelet aggregation, clot retraction, and spreading. Significantly, WY-14643 inhibits thrombin-induced activation of human washed platelets with an IC50 of 7.026 μM. The antiplatelet effect of WY-14643 is mainly dependent of GPIbα. CESTA, SPR and molecular docking results indicate that WY-14643 directly interacts with GPIbα and acts as a GPIbα antagonist. WY-14643 also inhibits phosphorylation of PLCγ2, Akt, p38, and Erk1/2 induced by thrombin. Noteworthily, 20 mg/kg oral administration of WY-14643 inhibits FeCl3-induced thrombosis of mesenteric arteries in mice similarly to clopidogrel without increasing bleeding.

CONCLUSION AND IMPLICATIONS

WY-14643 is not only a PPARα agonist with lipid-lowering effect, but also an antiplatelet agent as a GPIbα antagonist. It may have more significant therapeutic advantages than current antiplatelet agents for the treatment of atherosclerotic thrombosis, which have lipid-lowering effects without bleeding side effects.

MaiJiTong granule attenuates atherosclerosis by reducing ferroptosis via activating STAT6-mediated inhibition of DMT1 and SOCS1/p53 pathways in LDLR-/- mice

BACKGROUND AND PURPOSE

Atherosclerosis is the primary pathological basis of cardiovascular disease. Ferroptosis is a regulated form of cell death, a process of lipid peroxidation driven by iron, which can initiate and promote atherosclerosis. STAT6 is a signal transducer that shows a potential role in regulating ferroptosis, but, the exact role in ferroptosis during atherogenesis remains unclear. The Traditional Chinese Medicine Maijitong granule (MJT) is used for treating cardiovascular disease and shows a potential inhibitory effect on ferroptosis. However, the antiatherogenic effect and the underlying mechanism remain unclear. In this study, we determined the role of STAT6 in ferroptosis during atherogenesis, investigated the antiatherogenic effect of MJT, and determined whether its antiatherogenic effect was dependent on the inhibition of ferroptosis.

METHODS

8-week-old male LDLR-/- mice were fed a high-fat diet (HFD) at 1st and 10th week, respectively, to assess the preventive and therapeutic effects of MJT on atherosclerosis and ferroptosis. Simultaneously, the anti-ferroptotic effects and mechanism of MJT were determined by evaluating the expression of genes responsible for lipid peroxidation and iron metabolism. Subsequently, we reanalyzed microarray data in the GSE28117 obtained from cells after STAT6 knockdown or overexpression and analyzed the correlation between STAT6 and ferroptosis. Finally, the STAT6-/- mice were fed HFD and injected with AAV-PCSK9 to validate the role of STAT6 in ferroptosis during atherogenesis and revealed the antiatherogenic and anti-ferroptotic effect of MJT.

RESULTS

MJT attenuated atherosclerosis by reducing plaque lesion area and enhancing plaque stability in both preventive and therapeutic groups. MJT reduced inflammation via suppressing inflammatory cytokines and inhibited foam cell formation by lowering the LDL level and promoting ABCA1/G1-mediated lipid efflux. MJT ameliorated the ferroptosis by reducing lipid peroxidation and iron dysregulation during atherogenesis. Mechanistically, STAT6 negatively regulated ferroptosis by transcriptionally suppressing SOCS1/p53 and DMT1 pathways. MJT suppressed the DMT1 and SOCS1/p53 via stimulating STAT6 phosphorylation. In addition, STAT6 knockout exacerbated atherosclerosis and ferroptosis, which abolished the antiatherogenic and anti-ferroptotic effects of MJT.

CONCLUSION

STAT6 acts as a negative regulator of ferroptosis and atherosclerosis via transcriptionally suppressing DMT1 and SOCS1 expression and MJT attenuates atherosclerosis and ferroptosis by activating the STAT6-mediated inhibition of DMT1 and SOCS1/p53 pathways, which indicated that STAT6 acts a novel promising therapeutic target to ameliorate atherosclerosis by inhibiting ferroptosis and MJT can serve as a new therapy for atherosclerosis treatment.

Atherosclerotic Plaque Erosion: Mechanisms, Clinical Implications, and Potential Therapeutic Strategies-A Review

ABSTRACT

Atherosclerosis is an insidious and progressive inflammatory disease characterized by the formation of lipid-laden plaques within the intima of arterial walls with potentially devastating consequences. While rupture of vulnerable plaques has been extensively studied, a distinct mechanism known as plaque erosion (PE) has gained recognition and attention in recent years. PE, characterized by the loss of endothelial cell lining in the presence of intact fibrous cap, contributes to a significant and growing proportion of acute coronary events. However, despite a heterogeneous substrate underlying coronary thrombosis, treatment remains identical. This article provides an overview of atherosclerotic PE characteristics and its underlying mechanisms, highlights its clinical implications, and discusses potential therapeutic strategies.