A major role for VCAM-1, but not ICAM-1, in early atherosclerosis

Two Novel PET Radiopharmaceuticals for Endothelial Vascular Cell Adhesion Molecule-1 (VCAM-1) Targeting

Atherosclerosis is a chronic progressive disease involving inflammatory events, such as the overexpression of adhesion molecules including the endothelial Vascular Cell Adhesion Molecule-1 (VCAM-1). VCAM-1 is rapidly overexpressed in the first stages of atherosclerosis, thus representing a promising target for early atheroma detection. Two novel Positron Emission Tomography (PET) radiopharmaceuticals (MacroP and NAMP), based on the VCAM-1-binding peptide having sequence VHPKQHRGGSKGC, were synthesized and characterized. MacroP is derived from the direct conjugation of a DOTA derivative with the peptide, while NAMP is a biotin derivative conceived to be employed in a three-step pretargeting system, involving the use of a double-chelating derivative of DOTA. The identity of the newly synthesized radiopharmaceuticals was confirmed by mass spectrometry and, after radiolabeling with 68Ga, both showed high radiochemical purity; in vitro tests on human umbilical vein endothelial cells evidenced their VCAM-1 binding ability, with higher radioactive uptake in the case of NAMP. Moreover, NAMP might also be employed in a theranostic approach in association with functionalized biotinylated nanoparticles.

Leucine-Rich α-2-Glycoprotein 1 Suppresses Endothelial Cell Activation Through ADAM10-Mediated Shedding of TNF-α Receptor

Elevated serum concentrations of leucine-rich α-2-glycoprotein (LRG1) have been reported in patients with inflammatory, autoimmune, and cardiovascular diseases. This study aims to investigate the role of LRG1 in endothelial activation. LRG1 in endothelial cells (ECs) of arteries and serum of patients with critical limb ischemia (CLI) was assessed by immunohistochemistry and ELISA, respectively. LRG1 expression in sheared and tumor necrosis factor-α (TNF-α)-treated ECs was analyzed. The mechanistic role of LRG1 in endothelial activation was studied in vitro. Plasma of 37-week-old Lrg1 ^-/- mice was used to investigate causality between LRG1 and tumor necrosis factor receptor 1 (TNFR1) shedding. LRG1 was highly expressed in ECs of stenotic but not normal arteries. LRG1 concentrations in serum of patients with CLI were elevated compared to healthy controls. LRG1 expression was shear dependent. It could be induced by TNF-α, and the induction of its expression was mediated by NF-κB activation. LRG1 inhibited TNF-α-induced activation of NF-κB signaling, expression of VCAM-1 and ICAM-1, and monocyte capture, firm adhesion, and transendothelial migration. Mechanistically, LRG1 exerted its function by causing the shedding of TNFR1 via the ALK5-SMAD2 pathway and the subsequent activation of ADAM10. Consistent with this mechanism, LRG1 and sTNFR1 concentrations were correlated in the serum of CLI patients. Causality between LRG1 and TNFR1 shedding was established by showing that Lrg1 ^-/- mice had lower plasma sTNFR1 concentrations than wild type mice. Our results demonstrate a novel role for LRG1 in endothelial activation and its potential therapeutic role in inflammatory diseases should be investigated further.

B Cell Adhesion to Fibroblast-Like Synoviocytes Is Up-Regulated by Tumor Necrosis Factor-Alpha via Expression of Human Vascular Cell Adhesion Molecule-1 Mediated by B Cell-Activating Factor

Fibroblast-like synoviocytes (FLSs) play a key role in the pathogenesis of rheumatoid arthritis (RA) by producing inflammatory cytokines and interacting with various immune cells, which contribute to cartilage destruction. RA-FLSs activated by tumor necrosis factor alpha (TNF-α), exacerbate joint damage by triggering the expression of various inflammatory molecules, including human vascular cell adhesion molecule-1 (hVCAM1) and B cell-activating factor (hBAFF), with a role in maturation and maintenance of B cells. Here, we investigated whether B cell interaction with FLSs could be associated with hVCAM1 expression by TNF-α through hBAFF, using WiL2-NS B cells and MH7A synovial cells. TNF-α enhanced the expression of hVCAM1 and hBAFF. B cell adhesion to FLSs was increased by treatment with TNF-α or hBAFF protein. hVCAM expression was up-regulated by transcriptional activation of the hVCAM1 promoter(−1549 to −54) in MH7A cells treated with hBAFF protein or overexpressed with hBAFF gene. In contrast, hVCAM1 expression was down-regulated by treatment with hBAFF-siRNA. JNK was activated by TNF-α treatment. Then, hVCAM1 expression and B cell adhesion to FLSs were reduced by the treatment with JNK inhibitor SP600125. Transcriptional activity of hVCAM1 by the stimulation with TNF-α was inhibited by the deletion of −1549 to −229 from the hVCAM1 promoter. hVCAM1 expression and B cell adhesion to FLSs were reduced by treatment with hVCAM1-siRNA. Taken together, these results suggest that B cell adhesion to FLSs is associated with TNF-α-induced up-regulation of hVCAM1 expression via hBAFF expression. Thus, the pathological progression of RA may be associated with hVCAM1-mediated interaction of synovial cells with B lymphocytes.

Genetically engineered cell membrane-coated nanoparticles for targeted delivery of dexamethasone to inflamed lungs

As numerous diseases are associated with increased local inflammation, directing drugs to the inflamed sites can be a powerful therapeutic strategy. One of the common characteristics of inflamed endothelial cells is the up-regulation of vascular cell adhesion molecule-1 (VCAM-1). Here, the specific affinity between very late antigen-4 (VLA-4) and VCAM-1 is exploited to produce a biomimetic nanoparticle formulation capable of targeting inflammation. The plasma membrane from cells genetically modified to constitutively express VLA-4 is coated onto polymeric nanoparticle cores, and the resulting cell membrane-coated nanoparticles exhibit enhanced affinity to target cells that overexpress VCAM-1 in vitro. A model anti-inflammatory drug, dexamethasone, is encapsulated into the nanoformulation, enabling improved delivery of the payload to inflamed lungs and significant therapeutic efficacy in vivo. Overall, this work leverages the unique advantages of biological membrane coatings to engineer additional targeting specificities using naturally occurring target-ligand interactions.

Kinetics and prognostic value of soluble VCAM-1 in ST-segment elevation myocardial infarction patients

BACKGROUND

Soluble vascular cell adhesion molecule-1 (sVCAM-1) is a biomarker of endothelial activation and inflammation. There is still controversy as to whether it can predict clinical outcome after ST-elevation myocardial infarction (STEMI). Our aim was to assess the sVCAM-1 kinetics and to evaluate its prognostic predictive value.

METHOD

We prospectively enrolled 251 consecutive STEMI patients who underwent coronary revascularization in our university hospital. Blood samples were collected at admission, 4, 24, 48 h and 1 month after admission. sVCAM-1 serum level was assessed using ELISA assay. All patients had cardiac magnetic resonance imaging at 1-month for infarct size (IS) and left ventricular ejection fraction (LVEF) assessment. Clinical outcomes were recorded over 12 months after STEMI.

RESULTS

sVCAM-1 levels significantly increased from admission up to 1 month and were significantly correlated with IS, LVEF, and LV end-systolic and diastolic volume. (H48 area under curve (AUC) ≥ H48 median) were associated with an increased risk of adverse clinical events during the 12-month follow-up period with a hazard ratio (HR) = 2.6 (95% confidence interval [CI] of ratio = 1.2-5.6, p = .02). The ability of H48 AUC for sVCAM-1 to discriminate between patients with or without the composite endpoint was evaluated using receiver operating characteristics with an AUC at 0.67 (0.57-0.78, p = .004). This ability was significantly superior to H48 AUC creatine kinase (p = .03).

CONCLUSIONS

In STEMI patients, high sVCAM-1 levels are associated with a poor clinical outcome. sVCAM-1 is an early postmyocardial infarction biomarker and might be an interesting target for the development of future therapeutic strategies.

High-Density Lipoprotein Anti-Inflammatory Capacity and Incident Cardiovascular Events

BACKGROUND

The role of high-density lipoprotein (HDL) function in cardiovascular disease represents an important emerging concept. The present study investigated whether HDL anti-inflammatory capacity is prospectively associated with first cardiovascular events in the general population.

METHODS

HDL anti-inflammatory capacity was determined as its ability to suppress TNFα (tumor necrosis factor α)-induced VCAM-1 (vascular cell adhesion molecule-1) mRNA expression in endothelial cells in vitro (results expressed as achieved percent reduction by individual HDL related to the maximum TNFα effect with no HDL present). In a nested case-control design of the PREVEND (Prevention of Renal and Vascular End Stage Disease) study, 369 cases experiencing a first cardiovascular event (combined end point of death from cardiovascular causes, ischemic heart disease, nonfatal myocardial infarction, and coronary revascularization) during a median of 10.5 years of follow-up were identified and individually matched to 369 controls with respect to age, sex, smoking status, and HDL cholesterol. Baseline samples were available in 340 cases and 340 matched controls.

RESULTS

HDL anti-inflammatory capacity was not correlated with HDL cholesterol or hsCRP (high-sensitivity C-reactive protein). HDL anti-inflammatory capacity was significantly lower in cases compared with controls (31.6% [15.7-44.2] versus 27.0% [7.4-36.1]; P<0.001) and was inversely associated with incident CVD in a fully adjusted model (odds ratio [OR] per 1 SD, 0.74 [CI, 0.61-0.90]; P=0.002). Furthermore, this association was approximately similar with all individual components of the cardiovascular disease end point. The HDL anti-inflammatory was not correlated with cholesterol efflux capacity (r=-0.02; P>0.05). When combining these 2 HDL function metrics in 1 model, both were significantly and independently associated with incident cardiovascular disease in a fully adjusted model (efflux: OR per 1 SD, 0.74; P=0.002; anti-inflammatory capacity: OR per 1 SD, 0.66; P<0.001). Adding HDL anti-inflammatory capacity improved risk prediction by the Framingham risk score, with a model likelihood-ratio statistic increase from 10.50 to 20.40 (P=0.002).

CONCLUSIONS

The HDL anti-inflammatory capacity, reflecting vascular protection against key steps in atherogenesis, was inversely associated with incident cardiovascular events in a general population cohort, independent of HDL cholesterol and HDL cholesterol efflux capacity. Adding HDL anti-inflammatory capacity to the Framingham risk score improves risk prediction.

12-Hydroxyeicosapentaenoic acid inhibits foam cell formation and ameliorates high-fat diet-induced pathology of atherosclerosis in mice

Atherosclerosis is a chronic inflammatory disease associated with macrophage aggregate and transformation into foam cells. In this study, we sought to investigate the impact of dietary intake of ω3 fatty acid on the development of atherosclerosis, and demonstrate the mechanism of action by identifying anti-inflammatory lipid metabolite. Mice were exposed to a high-fat diet (HFD) supplemented with either conventional soybean oil or α-linolenic acid-rich linseed oil. We found that as mice became obese they also showed increased pulsatility and resistive indexes in the common carotid artery. In sharp contrast, the addition of linseed oil to the HFD improved pulsatility and resistive indexes without affecting weight gain. Histological analysis revealed that dietary linseed oil inhibited foam cell formation in the aortic valve. Lipidomic analysis demonstrated a particularly marked increase in the eicosapentaenoic acid-derived metabolite 12-hydroxyeicosapentaenoic acid (12-HEPE) in the serum from mice fed with linseed oil. When we gave 12-HEPE to mice with HFD, the pulsatility and resistive indexes was improved. Indeed, 12-HEPE inhibited the foamy transformation of macrophages in a peroxisome proliferator-activated receptor (PPAR)γ-dependent manner. These results demonstrate that the 12-HEPE-PPARγ axis ameliorates the pathogenesis of atherosclerosis by inhibiting foam cell formation.

The construction of multifunctional nanoparticles system for dual-modal imaging and arteriosclerosis targeted therapy

Atherosclerosis is a major risk factor for the development of cardiovascular disease. Unfortunately, due to relatively low sensitivities and poor resolution, the results of surgical resection are often largely unsatisfactory. Moreover, many chemotherapeutic agents, such as curcumin (Cur), are restricted by the low blood-brain barrier (BBB) permeability. Recently, nanotechnology proposes new opportunities to overcome these treatment barriers. In this study, superparamagnetic iron oxide nanoparticles (SPIO) was prepared by the high-temperature solid-state method, and then loaded into amphiphilic polymer DSPE-PEG to form SDP nanoparticles by hydrogen bonding in oil phase. The curcumin was encapsulated in SDP nanoparticles by self-assembly. Finally, vascular cell adhesion molecule-1 (VCAM-1) and Cy5.5 were conjugated on into SDP/Cur nanoparticles by amidation reaction. The average particle size of the prepared multifunctional SDP-VCAM-1/Cur/Cy5.5 nanoparticles is 124.4 nm, which can provide the sustained release of Cur. Moreover, the nanoparticles are proved to have superparamagnetic properties and fluorescence properties. In vitro cell experiments show that nanoparticles have excellent biocompatibility, blood compatibility and macrophage targeting. These results show that SDP-VCAM-1/Cur/Cy5.5 nanoparticles can be used not only as dual imaging probe for magnetic resonance (MR) and fluorescence imaging, but also as carriers to deliver chemotherapeutic drugs to inflammatory tissue, thus providing a promising opportunity for the treatment, molecular imaging and targeted therapy in atherosclerosis due to their established specificity and safety.

Treatment of atherosclerosis through transplantation of endothelial progenitor cells overexpressing dimethylarginine dimethylaminohydrolase (DDAH) in rabbits

BACKGROUND

Endothelial dysfunction is a key event in the development of vascular diseases, including atherosclerosis. Endothelial progenitor cells (EPCs) play an important role in vascular repair. Decreased dimethylarginine dimethylaminohydrolase (DDAH) activity is observed in several pathological conditions, and it is associated with an increased risk of vascular disease. We hypothesized that bone marrow-derived EPCs and combination therapy with DDAH2-EPCs could reduce plaque size and ameliorate endothelial dysfunction in an atherosclerosis rabbit model.

METHOD

Four groups of rabbits (n = 8 per group) were subjected to a hyperlipidemic diet for a month. After establishing the atherosclerosis model, rabbits received 4 × 106 EPC, EPCs expressing DDAH2, through femoral vein injection, or saline (the control group with basic food and the untreated group). One month after transplantation, plaque thickness, endothelial function, oxidative stress, and inflammatory mRNAs, DDAH, and eNOS function were assessed.

RESULTS

DDAH2-EPCs transplantation (p < 0.05) and EPCs transplantation (p < 0.05) were both associated with a reduction in plaque size compared to the control saline injection. The antiproliferative and antiatherogenic effects of EPCs were further enhanced by the overexpression of DDAH2 (p < 0.05, DDAH2-EPCs vs. EPCs). Furthermore, DDAH2-EPCs transplantation significantly increased endothelium integrity compared to the EPCs transplantation.

CONCLUSION

Transplantation of EPCs overexpressing DDAH2 may enhance the repair of injured endothelium by reducing inflammation and restoring endothelial function. Therefore, pCMV6-mediated DDAH2 gene-transfected EPCs are a potentially valuable tool for the treatment of atherosclerosis.

VCAM-1 as a predictor biomarker in cardiovascular disease

The vascular cellular adhesion molecule-1 (VCAM-1) is a protein that canonically participates in the adhesion and transmigration of leukocytes to the interstitium during inflammation. VCAM-1 expression, together with soluble VCAM-1 (sVCAM-1) induced by the shedding of VCAM-1 by metalloproteinases, have been proposed as biomarkers in immunological diseases, cancer, autoimmune myocarditis, and as predictors of mortality and morbidity in patients with chronic heart failure (HF), endothelial injury in patients with coronary artery disease, and arrhythmias. This revision aims to discuss the role of sVCAM-1 as a biomarker to predict the occurrence, development, and preservation of cardiovascular disease.

Mechanotransduction-on-chip: vessel-chip model of endothelial YAP mechanobiology reveals matrix stiffness impedes shear response

Endothelial mechanobiology is a key consideration in the progression of vascular dysfunction, including atherosclerosis. However mechanistic connections between the clinically associated physical stimuli, vessel stiffness and shear stress, and how they interact to modulate plaque progression remain incompletely characterized. Vessel-chip systems are excellent candidates for modeling vascular mechanobiology as they may be engineered from the ground up, guided by the mechanical parameters present in human arteries and veins, to recapitulate key features of the vasculature. Here, we report extensive validation of a vessel-chip model of endothelial yes-associated protein (YAP) mechanobiology, a protein sensitive to both matrix stiffness and shearing forces and, importantly, implicated in atherosclerotic progression. Our model captures the established endothelial mechanoresponse, with endothelial alignment, elongation, reduction of adhesion molecules, and YAP cytoplasmic retention under high laminar shear. Conversely, we observed disturbed morphology, inflammation, and nuclear partitioning under low, high, and high oscillatory shear. Examining targets of YAP transcriptional co-activation, connective tissue growth factor (CTGF) is strongly downregulated by high laminar shear, whereas it is strongly upregulated by low shear or oscillatory flow. Ankyrin repeat domain 1 (ANKRD1) is only upregulated by high oscillatory shear. Verteporfin inhibition of YAP reduced the expression of CTGF but did not affect ANKRD1. Lastly, substrate stiffness modulated the endothelial shear mechanoresponse. Under high shear, softer substrates showed the lowest nuclear localization of YAP whereas stiffer substrates increased nuclear localization. Low shear strongly increased nuclear localization of YAP across stiffnesses. Together, we have validated a model of endothelial mechanobiology and describe a clinically relevant biological connection between matrix stiffness, shear stress, and endothelial activation via YAP mechanobiology.

Urolithiasis Develops Endothelial Dysfunction as a Clinical Feature

An increased risk of cardiovascular morbidity has been reported in lithiasic patients. In this context, endothelial dysfunction (ED), an earlier status of atherogenesis, has been identified in hyperoxaluria rat models of urolithiasis. Objective: The purpose of this study was to determine the endothelial vascular function in patients with urolithiasis in relation to systemic inflammatory, oxidative stress, and vascular function serum markers. Methods: A cross-sectional study was performed between 27 urolithiasic patients, matched for age and sex, with 27 healthy patients. Endothelial function was assessed by measuring flow-mediated dilation (Celermajer method). Fasting blood was collected to determine metabolic parameters (glucose and lipid profile), along with serum CRP, IL-6, MDA, ADMA, and VCAM-1. Results: Both the control and urolithiasis groups were homogenous in anthropometric, exploration, and general laboratory measures. Flow-mediated dilation (%FMD) was 11.85% (SE: 2.78) lower in the lithiasis group (p < 0.001). No significant differences were achieved between groups when CRP, IL-6, MDA, ADMA, and VCAM-1 were compared, although slightly higher values of CRP, ADMA, and VCAM-1 were detected in the lithiasic group. A correlation was not reached in any of the serum markers when they were related to flow-mediated values, although a slight negative correlation trend was observed in MDA, VCAM-1, and IL-6 values. Conclusions: Endothelial dysfunction constitutes an important disorder related to urolithiasis patients. It must be considered as an early feature responsible for future cardiovascular events. Our study did not find a significant association between inflammatory, oxidative stress, endothelial serum markers, and flow-mediated dilation.

Contribution of ADAM17 and related ADAMs in cardiovascular diseases

A disintegrin and metalloproteases (ADAMs) are key mediators of cell signaling by ectodomain shedding of various growth factors, cytokines, receptors and adhesion molecules at the cellular membrane. ADAMs regulate cell proliferation, cell growth, inflammation, and other regular cellular processes. ADAM17, the most extensively studied ADAM family member, is also known as tumor necrosis factor (TNF)-α converting enzyme (TACE). ADAMs-mediated shedding of cytokines such as TNF-α orchestrates immune system or inflammatory cascades and ADAMs-mediated shedding of growth factors causes cell growth or proliferation by transactivation of the growth factor receptors including epidermal growth factor receptor. Therefore, increased ADAMs-mediated shedding can induce inflammation, tissue remodeling and dysfunction associated with various cardiovascular diseases such as hypertension and atherosclerosis, and ADAMs can be a potential therapeutic target in these diseases. In this review, we focus on the role of ADAMs in cardiovascular pathophysiology and cardiovascular diseases. The main aim of this review is to stimulate new interest in this area by highlighting remarkable evidence.

Anti-Vascular Cell Adhesion Molecule-1 Nanosystems: A Promising Strategy Against Inflammatory Based Diseases

Inflammation underlays the onset and supports the development of several worldwide diffused pathologies, therefore in the last decades inflammatory markers have attracted a great deal of interest as diagnostic and therapeutic targets. Adhesion molecules are membrane proteins expressed by endotheliocytes and leukocytes, acting as mediators in the process of tethering, rolling, firm adhesion and diapedesis that leads the immune cells to reach an inflamed tissue. Among them, the adhesion molecule VCAM-1 has been investigated as a potential target because of its low constitutive expression and easy accessibility on the endothelium. Moreover, VCAM-1 is involved in the early stages of development of several pathologies like, among others, atherosclerosis, cancer, Alzheimer's and Parkinson's diseases, so a diagnostic or therapeutic tool directed to this protein would allow specific detection and efficacious intervention. The availability of monoclonal antibodies against VCAM-1 has recently fostered the development of various targeting technologies potentially suitable for imaging and drug delivery in VCAM-1 overexpressing pathologies. In this review we initially focus on the structure and functions of VCAM-1, giving also a brief overview of antibodies origin, structure and function; then, we summarize some of the VCAM-1 targeting nanosystems based on antibodies, gathered according to the carrier used, for diagnosis or therapeutic treatment of different inflammatory based pathologies.

Updating concepts on atherosclerotic inflammation: From pathophysiology to treatment

BACKGROUND

Atherosclerosis is recognized as a systemic low-grade inflammatory disease. Furthermore, the dysregulation of the inflammatory response and its timely resolution is a pivotal process in determining the clinical manifestations of cardiac and cerebral acute ischaemia following atherothrombosis.

METHODS

This narrative review is based on the material searched on PubMed up to October 2020. The search terms we used were as follows: "atherosclerosis, inflammation, acute myocardial infarction and ischemic stroke" in combination with "biomarker, inflammatory cells and molecules, treatment."

RESULTS

The expected goal of addressing inflammation for the treatment of atherosclerosis and its acute ischaemic complications is reducing mortality and morbidity related to atherosclerotic cardiovascular disease, which are currently the first cause of death and disability worldwide. In this narrative review, we summarize the evidence about the main cellular and molecular mechanisms of inflammation in atherogenesis, atherothrombosis and acute ischaemic complications, with particular focus on the potential molecular targets for novel pharmacological treatments.

CONCLUSION

Although a large amount of evidence from animal models of atherothrombotic disease, and promising results of clinical trials, anti-inflammatory treatments against atherosclerosis are not yet recommended. A deepest understanding of pathophysiological mechanisms underlying the mechanisms driving resolution of the acute inflammation will probably allow to identify the optimal molecular target.

Efficacy of the Piperidine Nitroxide 4-MethoxyTEMPO in Ameliorating Serum Amyloid A-Mediated Vascular Inflammation

Intracellular redox imbalance in endothelial cells (EC) can lead to endothelial dysfunction, which underpins cardiovascular diseases (CVD). The acute phase serum amyloid A (SAA) elicits inflammation through stimulating production of reactive oxygen species (ROS). The cyclic nitroxide 4-MethoxyTEMPO (4-MetT) is a superoxide dismutase mimetic that suppresses oxidant formation and inflammation. The aim of this study was to investigate whether 4-MetT inhibits SAA-mediated activation of cultured primary human aortic EC (HAEC). Co-incubating cells with 4-MetT inhibited SAA-mediated increases in adhesion molecules (VCAM-1, ICAM-1, E-selectin, and JAM-C). Pre-treatment of cells with 4-MetT mitigated SAA-mediated increases in transcriptionally activated NF-κB-p65 and P120 Catenin (a stabilizer of Cadherin expression). Mitochondrial respiration and ROS generation (mtROS) were adversely affected by SAA with decreased respiratory reserve capacity, elevated maximal respiration and proton leakage all characteristic of SAA-treated HAEC. This altered respiration manifested as a loss of mitochondrial membrane potential (confirmed by a decrease in TMRM fluorescence), and increased mtROS production as assessed with MitoSox Red. These SAA-linked impacts on mitochondria were mitigated by 4-MetT resulting in restoration of HAEC nitric oxide bioavailability as confirmed by assessing cyclic guanosine monophosphate (cGMP) levels. Thus, 4-MetT ameliorates SAA-mediated endothelial dysfunction through normalising EC redox homeostasis. Subject to further validation in in vivo settings; these outcomes suggest its potential as a therapeutic in the setting of cardiovascular pathologies where elevated SAA and endothelial dysfunction is linked to enhanced CVD.

LCZ696 ameliorates lipopolysaccharide-induced endothelial injury

Lipopolysaccharide (LPS)-induced endothelial dysfunction plays an important role in the pathogenesis of cardiovascular diseases. LCZ696, the dual-acting angiotensin receptor blocker, and neprilysin inhibitor has been used for the treatment of heart failure with reduced ejection fraction. Recent work suggests that LCZ696 therapy might have an anti-inflammatory effect in cardiovascular tissue. In the current study, we show that LCZ696 attenuates LPS-induced oxidative stress by reducing the production of intracellular reactive oxygen species (ROS) and the measurements of malonyl dialdehyde (MDA) level in human umbilical vascular endothelial cells (HUVECs). LCZ696 inhibits LPS-induced expressions and secretions of the pro-inflammatory cytokines, interleukin-6 (IL-6), interleukin-1α (IL-1α), and tumor necrosis factor β (TNF-β) as well as the chemokines, monocyte chemotactic protein 1 (MCP-1), and chemokine (C-X-C motif) ligand 1 protein (CXCL1). Additionally, we found that LCZ696 reduces LPS-induced expressions of vascular cell adhesion molecule 1 (VCAM-1) and P-selectin and the attachment of U937 monocytes to HUVECs. Mechanistically, LCZ696 prevents LPS-induced activation of the TLR4/Myd88 pathway and nuclear translocation of nuclear factor kappa-B (NF-κB) p65 factor. Based on these findings, we conclude that LCZ696 is capable of ameliorating LPS-induced endothelial dysfunction via anti-inflammatory properties.

Targeting macrophages using nanoparticles: a potential therapeutic strategy for atherosclerosis

Atherosclerosis is one of the leading causes of vascular diseases, with high morbidity and mortality worldwide. Macrophages play a critical role in the development and local inflammatory responses of atherosclerosis, contributing to plaque rupture and thrombosis. Considering their central roles, macrophages have gained considerable attention as a therapeutic target to attenuate atherosclerotic progression and stabilize existing plaques. Nanoparticle-based delivery systems further provide possibilities to selectively and effectively deliver therapeutic agents into intraplaque macrophages. Although challenges are numerous and clinical application is still distant, the design and development of macrophage-targeting nanoparticles will generate new knowledge and experiences to improve therapeutic outcomes and minimize toxicity. Hence, the review aims to discuss various strategies for macrophage modulation and the development and evaluation of macrophage targeting nanomedicines for anti-atherosclerosis.

Endothelial Barrier Function and Leukocyte Transmigration in Atherosclerosis

The vascular endothelium is a highly specialized barrier that controls passage of fluids and migration of cells from the lumen into the vessel wall. Endothelial cells assist leukocytes to extravasate and despite the variety in the specific mechanisms utilized by different leukocytes to cross different vascular beds, there is a general principle of capture, rolling, slow rolling, arrest, crawling, and ultimately diapedesis via a paracellular or transcellular route. In atherosclerosis, the barrier function of the endothelium is impaired leading to uncontrolled leukocyte extravasation and vascular leakage. This is also observed in the neovessels that grow into the atherosclerotic plaque leading to intraplaque hemorrhage and plaque destabilization. This review focuses on the vascular endothelial barrier function and the interaction between endothelial cells and leukocytes during transmigration. We will discuss the role of endothelial dysfunction, transendothelial migration of leukocytes and plaque angiogenesis in atherosclerosis.

HDAC1 and 2 regulate endothelial VCAM-1 expression and atherogenesis by suppressing methylation of the GATA6 promoter

Increased expression of vascular cell adhesion molecule (VCAM)-1 on the activated arterial endothelial cell (EC) surface critically contributes to atherosclerosis which may in part be regulated by epigenetic mechanisms. This study investigated whether and how the clinically available histone deacetylases 1 and 2 (HDAC1/2) inhibitor drug Romidepsin epigenetically modulates VCAM-1 expression to suppress atherosclerosis.

Methods: VCAM-1 expression was analyzed in primary human aortic EC (HAEC) treated with Romidepsin or transfected with HDAC1/2-targeting siRNA. Methylation of GATA6 promoter region was examined with methylation-specific PCR assay. Enrichment of STAT3 to GATA6 promoter was detected with chromatin immunoprecipitation. Lys685Arg mutation was constructed to block STAT3 acetylation. The potential therapeutic effect of Romidepsin on atherosclerosis was evaluated in Apoe^-/- mice fed with a high-fat diet.

Results: Romidepsin significantly attenuated TNFα-induced VCAM-1 expression on HAEC surface and monocyte adhesion through simultaneous inhibition of HDAC1/2. This downregulation of VCAM-1 was attributable to reduced expression of transcription factor GATA6. Romidepsin enhanced STAT3 acetylation and its binding to DNA methyltransferase 1 (DNMT1), leading to hypermethylation of the GATA6 promoter CpG-rich region at +140/+255. Blocking STAT3 acetylation at Lys685 disrupted DNMT1-STAT3 interaction, decreased GATA6 promoter methylation, and reversed the suppressive effects of HDAC1/2 inhibition on GATA6 and VCAM-1 expression. Finally, intraperitoneal administration of Romidepsin reduced diet-induced atherosclerotic lesion development in Apoe^-/- mice, accompanied by a reduction in GATA6/VCAM-1 expression in the aorta.

Conclusions: HDAC1/2 contributes to VCAM-1 expression and atherosclerosis by suppressing STAT3 acetylation-dependent GATA6 promoter methylation. These findings may provide a rationale for HDAC1/2-targeting therapy in atherosclerotic heart disease.

Wnt signaling enhances macrophage responses to IL-4 and promotes resolution of atherosclerosis

Atherosclerosis is a disease of chronic inflammation. We investigated the roles of the cytokines IL-4 and IL-13, the classical activators of STAT6, in the resolution of atherosclerosis inflammation. Using Il4-/-Il13-/- mice, resolution was impaired, and in control mice, in both progressing and resolving plaques, levels of IL-4 were stably low and IL-13 was undetectable. This suggested that IL-4 is required for atherosclerosis resolution, but collaborates with other factors. We had observed increased Wnt signaling in macrophages in resolving plaques, and human genetic data from others showed that a loss-of-function Wnt mutation was associated with premature atherosclerosis. We now find an inverse association between activation of Wnt signaling and disease severity in mice and humans. Wnt enhanced the expression of inflammation resolving factors after treatment with plaque-relevant low concentrations of IL-4. Mechanistically, activation of the Wnt pathway following lipid lowering potentiates IL-4 responsiveness in macrophages via a PGE2/STAT3 axis.

IRF2BP2 prevents ox-LDL-induced inflammation and EMT in endothelial cells via regulation of KLF2

Oxidized low-density lipoprotein (ox-LDL)-induced endothelial dysfunction contributes to the progression of atherosclerosis. Interferon regulatory factor 2-binding protein 2 (IRF2BP2) attenuates macrophage-mediated inflammation and susceptibility to atherosclerosis. However, the effects of IRF2BP2 on vascular endothelial cells in atherosclerosis have not been fully elucidated. In the present study, the effects of IRF2BP2 on cell viability, inflammation and endothelial-to-mesenchymal transition (EMT) of human umbilical vein endothelial cells (HUVECs) were assessed using Cell Counting Kit-8 (CCK-8) assays, ELISA kits and western blot analysis, respectively. In addition, the expression levels of Krüppel-like factor 2 (KLF2) were determined by reverse transcription-quantitative PCR and immunofluorescence assays. A Nitrate/Nitrite assay kit was utilized to detect the production of nitric oxide (NO). The results demonstrated that ox-LDL induced inflammation and EMT of HUVECs, and decreased the NO levels. Furthermore, IRF2BP2 overexpression protected HUVECs against ox-LDL-induced inflammation, EMT and endothelial dysfunction, and resulted in upregulated expression of KLF2. Additionally, IRF2BP2 was shown to bind to KLF2, and KLF2 knockdown reversed the protective effects of IRF2BP2 on ox-LDL-exposed HUVECs. These findings indicated that IRF2BP2 may prevent ox-LDL-induced endothelial damage via upregulating KLF2 expression.

Fluorescent nanocarriers targeting VCAM-1 for early detection of senescent endothelial cells

Endothelial senescence has been identified as an early event in the development of endothelial dysfunction, a hallmark of cardiovascular disease. This study developed theranostic nanocarriers (NC) decorated with VCAM-1 antibodies (NC-VCAM-1) in order to target cell surface VCAM-1, which is overexpressed in senescent endothelial cells (ECs) for diagnostic and therapeutic purposes. Incubation of Ang II-induced premature senescent ECs or replicative senescent ECs with NC-VCAM-1 loaded with lipophilic fluorescent dyes showed higher fluorescence signals than healthy EC, which was dependent on the NC size and VCAM-1 antibodies concentration, and not observed following masking of VCAM-1. NC loaded with omega 3 polyunsaturated fatty acid (NC-EPA:DHA6:1) were more effective than native EPA:DHA 6:1 to prevent Ang II-induced VCAM-1 and p53 upregulation, and SA-β-galactosidase activity in coronary artery segments. These theranostic NC might be of interest to evaluate the extent and localization of endothelial senescence and to prevent pro-senescent endothelial responses.

PRDX2 Protects Against Atherosclerosis by Regulating the Phenotype and Function of the Vascular Smooth Muscle Cell

Peroxiredoxin 2 (PRDX2), an inhibitor of reactive oxygen species (ROS), is potentially involved in the progression of atherosclerosis (AS). The aim of this study was to explore the role and mechanism of PRDX2 in AS. The expression of PRDX2 was evaluated in 14 human carotid artery tissues with or without AS. The results showed that the positive reaction of PRDX2 was observed in the carotid artery vascular smooth muscle cells (CAVSMCs). To assess the mechanism by which PRDX2 may function in AS, the CAVSMCs were transfected with pEX4-PRDX2 and si-PRDX2. The catalase, hydrogen peroxide (H₂O₂) scavenger, was used to further confirm that PRDX2-induced inhibitory effects might be mediated through reducing ROS levels. Phenotype alteration and functional testing included transcription testing, immunostaining, and expression studies. The drug of MAPK signaling pathway inhibitors SB203580, SP600125, and PD98059 was used to evaluate the underlying mechanism. In this study, we found that the protein level of PRDX2 and the level of H₂O₂ were higher in the human AS carotid artery tissues than in the normal carotid artery tissues, accompanied with the activation of MAPK signaling pathway. The up-regulation of PRDX2 in the CAVSMCs significantly decreased the expression of ROS, collagen type I (COL I), collagen type III (COL III), vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) and inhibited the proliferation, migration, and transformation of the CAVSMCs. The up-regulation of PRDX2 reversed the effect of the CAVSMCs treated with tumor necrosis factor-α (TNF-α). In addition, PRDX2 down-regulation promoted the protein levels of p-p38, p-JNK, and p-ERK, which was confirmed in relevant MAPK inhibitor treatment experiments. Our results suggest a protective role of PRDX2, as a scavenger of ROS, in AS progression through inhibiting the VSMC phenotype alteration and function via MAPK signaling pathway.

Inflammatory Cell Recruitment in Cardiovascular Disease

Atherosclerosis, the main underlying pathology for myocardial infarction and stroke, is a chronic inflammatory disease of middle-sized to large arteries that is initiated and maintained by leukocytes infiltrating into the subendothelial space. It is now clear that the accumulation of pro-inflammatory leukocytes drives progression of atherosclerosis, its clinical complications, and directly modulates tissue-healing in the infarcted heart after myocardial infarction. This inflammatory response is orchestrated by multiple soluble mediators that enhance inflammation systemically and locally, as well as by a multitude of partially tissue-specific molecules that regulate homing, adhesion, and transmigration of leukocytes. While numerous experimental studies in the mouse have refined our understanding of leukocyte accumulation from a conceptual perspective, only a few anti-leukocyte therapies have been directly validated in humans. Lack of tissue-tropism of targeted factors required for leukocyte accumulation and unspecific inhibition strategies remain the major challenges to ultimately translate therapies that modulate leukocytes accumulation into clinical practice. Here, we carefully describe receptor and ligand pairs that guide leukocyte accumulation into the atherosclerotic plaque and the infarcted myocardium, and comment on potential future medical therapies.

Anti-Inflammatory Effect and Cellular Transport Mechanism of Phenolics from Common Bean (Phaseolus vulga L.) Milk and Yogurts in Caco-2 Mono- and Caco-2/EA.hy926 Co-Culture Models

The bioavailability and anti-inflammatory activity of the phenolic compounds derived from gastrointestinal digestates of navy bean and light red kidney bean milks and yogurts were investigated in both Caco-2 mono- and Caco-2/EA.hy926 co-culture cell models. Instead of being transported directly, the ferulic acid ester derivatives in common bean milks and yogurts were found to be metabolized into ferulic acid and then be transported through the Caco-2 cell monolayer with an average basolateral ferulic acid concentration of 56 ± 3 ng/mL after 2 h. Strong anti-inflammatory effects were observed in the basolateral EA.hy926 cells of the co-culture model, and modulations of oxLDL-induced inflammatory mediators by the transported phenolics were verified to be through the p38 MAPK pathway. The present results suggest that the common bean-derived phenolics can be metabolized and absorbed by the intestinal epithelial cells and have antioxidant and anti-inflammatory effects against oxidative stress injury in vascular endothelial cells, hence contributing to the amelioration of vascular diseases.

The Endothelium as a Target for Anti-Atherogenic Therapy: A Focus on the Epigenetic Enzymes EZH2 and SIRT1

Endothelial cell inflammatory activation and dysfunction are key events in the pathophysiology of atherosclerosis, and are associated with an elevated risk of cardiovascular events. Yet, therapies specifically targeting the endothelium and atherosclerosis are lacking. Here, we review how endothelial behaviour affects atherogenesis and pose that the endothelium may be an efficacious cellular target for antiatherogenic therapies. We discuss the contribution of endothelial inflammatory activation and dysfunction to atherogenesis and postulate that the dysregulation of specific epigenetic enzymes, EZH2 and SIRT1, aggravate endothelial dysfunction in a pleiotropic fashion. Moreover, we propose that commercially available drugs are available to clinically explore this postulation.

β-Aminoisobutyric Acid Suppresses Atherosclerosis in Apolipoprotein E-Knockout Mice

Endurance exercise training has been shown to induce peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) expression in skeletal muscle. We recently reported that skeletal muscle-specific PGC-1α overexpression suppressed atherosclerosis in apolipoprotein E-knockout (ApoE^-/-) mice. β-Aminoisobutyric acid (BAIBA) is a PGC-1α-dependent myokine secreted from myocytes that affects multiple organs. We have also reported that BAIBA suppresses tumor necrosis factor-alpha-induced vascular cell adhesion molecule-1 (VCAM-1) and monocyte chemoattractant protein-1 (MCP-1) gene expression in endothelial cells. In the present study, we hypothesized that BAIBA suppresses atherosclerosis progression, and tested that hypothesis with ApoE^-/- mice. The mice were administered water containing BAIBA for 14 weeks, and were then sacrificed at 20 weeks of age. Atherosclerotic plaque area, plasma BAIBA concentration, and plasma lipoprotein profiles were assessed. Immunohistochemical analyses of the plaque were performed to assess VCAM-1 and MCP-1 protein expression levels and macrophage infiltration. The results showed that BAIBA administration decreased atherosclerosis plaque area by 30%, concomitant with the elevation of plasma BAIBA levels. On the other hand, plasma lipoprotein profiles were not changed by the administration. Immunohistochemical analyses indicated reductions in VCAM-1, MCP-1, and Mac-2 protein expression levels in the plaque. These results suggest that BAIBA administration suppresses atherosclerosis progression without changing plasma lipoprotein profiles. We propose that the mechanisms of this suppression are reductions in both VCAM-1 and MCP-1 expression as well as macrophage infiltration into the plaque.

Nanobody: a promising toolkit for molecular imaging and disease therapy

Nanobodies are the recombinant variable domains of heavy-chain-only antibodies, with many unique properties such as small size, excellent solubility, superior stability, quick clearance from blood, and deep tissue penetration. As a result, nanobodies have become a promising tool for the diagnosis and therapy of diseases. As imaging tracers, nanobodies allow an early acquisition of high-quality images, provide a comprehensive evaluation of the disease, and subsequently enable a personalized precision therapy. As therapeutic agents, nanobodies enable a targeted therapy by lesion-specific delivery of drugs and effector domains, thereby improving the specificity and efficacy of the therapy. Up to date, a wide variety of nanobodies have been developed for a broad range of molecular targets and have played a significant role in patients with a broad spectrum of diseases. In this review, we aim to outline the current state-of-the-art research on the nanobodies for medical applications and then discuss the challenges and strategies for their further clinical translation.

Skeletal muscle-specific forkhead box protein-O1 overexpression suppresses atherosclerosis progression in apolipoprotein E-knockout mice

Calorie restriction (CR) reportedly prevents atherosclerotic diseases. Furthermore, CR induces forkhead box protein-O1 (FOXO-1) expression in the skeletal muscle, altering the character of the skeletal muscle. We previously reported that the change in skeletal muscle character, induced by the overexpression of peroxisome proliferator-activated receptor γ coactivator-1α, suppresses atherosclerotic progression in an atherosclerotic apolipoprotein E-knockout (ApoE-KO) mouse model. Thus, we hypothesized that skeletal muscle alternation induced by FOXO-1 may also have an anti-atherosclerotic effect in ApoE-KO mice. In this study, we investigated whether skeletal muscle-specific FOXO-1 overexpression suppresses the progression of atherosclerosis in ApoE-KO mice. We generated ApoE-KO/FOXO-1 mice, in which an ApoE-KO mouse was crossbred with a mouse presenting skeletal muscle-specific FOXO-1 overexpression (FOXO-1Tg). The mice were sacrificed at 20 weeks of age, and atherosclerotic plaque area and protein expression in the plaque were measured. Additionally, we measured the tumor necrosis factor α (TNFα)- induced mRNA expression in human umbilical vein endothelial cells (HUVECs), using serum collected from the FOXO-1Tg mice. Accordingly, ApoE-KO/FOXO-1 mice showed a 65% reduced atherosclerotic plaque area when compared with the ApoE-KO mice, with concomitantly reduced vascular cell adhesion molecule-1 (VCAM-1) and macrophage infiltration. As compared to serum from wild-type mice, the serum collected from the FOXO-1Tg mice significantly suppressed the mRNA expression of VCAM-1, an atherosclerosis initiation factor, in TNFα-treated HUVECs. Therefore, these data suggest that skeletal muscle-specific FOXO-1 overexpression suppresses the progression of atherosclerosis in ApoE-KO mice. In part, the CR-induced anti-atherosclerotic effect could be attributed to FOXO-1 upregulation in the skeletal muscle.

An overview of the innate and adaptive immune system in atherosclerosis

Cardiovascular disease is the leading cause of death globally. Coronary artery disease (CAD) is a chronic inflammatory disease usually caused by atherosclerosis, in which the coronary arteries become narrowed by atheromatous plaque. Plaques in atherosclerosis are formed through the accumulation of lipids and various immune cells. Both adaptive and innate immune systems are involved in the pathogenesis of atherosclerosis and facilitate plaque formation and disease progression. Almost all immune system cells, including neutrophils, B cells, T cells monocytes, macrophages, foam cells, and dendritic cells (DCs), play a vital role in atherosclerotic plaque. Atherogenesis, the normal function of the endothelium, is initially disrupted and, then, cells of the immune system are recruited to the endothelium following increased expression of cell adhesion molecules. Accumulation of immune cells and lipids leads to the formation of a necrotic nucleus. As the disease progresses, smooth muscle cells form fibrous layers, whose rupture results in exposing the necrotic nucleus and thrombosis. Accordingly, the present review was conducted to determine the role of different cells in innate and adaptive immune systems in inhibition and progression of atherosclerosis.

A Comparative Analysis of the Lipoprotein(a) and Low-Density Lipoprotein Proteomic Profiles Combining Mass Spectrometry and Mendelian Randomization

Background

Lipoprotein(a) (Lp[a]), which consists of a low-density lipoprotein (LDL) bound to apolipoprotein(a), is one of the strongest genetic risk factors for atherosclerotic cardiovascular diseases. Few studies have performed hypothesis-free direct comparisons of the Lp(a) and the LDL proteomes. Our objectives were to compare the Lp(a) and the LDL proteomic profiles and to evaluate the effect of lifelong exposure to elevated Lp(a) or LDL cholesterol levels on the plasma proteomic profile.

Methods

We performed a label-free analysis of the Lp(a) and LDL proteomic profiles of healthy volunteers in a discovery (n = 6) and a replication (n = 9) phase. We performed inverse variance weighted Mendelian randomization to document the effect of lifelong exposure to elevated Lp(a) or LDL cholesterol levels on the plasma proteomic profile of participants of the INTERVAL study.

Results

We identified 15 proteins that were more abundant on Lp(a) compared with LDL (serping1, pi16, itih1, itih2, itih3, pon1, podxl, cd44, cp, ptprg, vtn, pcsk9, igfals, vcam1, and ttr). We found no proteins that were more abundant on LDL compared with Lp(a). After correction for multiple testing, lifelong exposure to elevated LDL cholesterol levels was associated with the variation of 18 plasma proteins whereas Lp(a) did not appear to influence the plasma proteome.

Conclusions

Results of this study highlight marked differences in the proteome of Lp(a) and LDL as well as in the effect of lifelong exposure to elevated LDL cholesterol or Lp(a) on the plasma proteomic profile.

The role of 18FDG PET/CT imaging of aortic atherosclerosis: prospective study and technique optimization

Background

Atherosclerosis is an inflammatory disease of the inner wall of large and medium-sized arteries. The progress of atherosclerosis based on a lot of factors, including systemic involvement of disease, the precise vascular arterial affection, and the degree of flow obstruction. We aim in this study to estimate the FDG uptake of the aortic wall in the early and delayed imaging and to correlate this with the morphologic changes detected by CT.

Results

This is a prospective study that was performed through 1 year. The study included 50 patients [30 males (60%) and 20 females (40%)] with male to female mean ratio 1.5:1 and their mean age 58.3 ± 15.7 years. Each patient underwent dual time-point 18F-FDG PET CT imaging at ~ 60 min (Early images) and 180 min (delayed images) after the administration of 18F-FDG. For each patient, the global 18F-FDG uptake in the aorta was determined by manually drawing regions of interest (ROIs) around the outer part of the arterial wall on every slice of the attenuation-corrected transverse PET CT images. Per-patient, per-time-point, per-vessel, and per-ROI radiotracer decay-corrected and body weight-corrected SUVs were calculated, resulting in a single mean value of maximum SUV for the aorta. The aortic wall FDG uptake was measured in both early and delayed images and expressed in terms of SUVmax. Then Retention index percentage of the aorta was measured. The retention index percentage was calculated by subtracting the SUVmax in early images from the SUVmax in delayed images and dividing by SUVmax in early images.

Conclusion

Aortic wall FDG uptake can be used as an additional parameter as well as a biomarker on evaluation of the arterial atherosclerotic activity. Delayed post 3 h FDG imaging is more accurate than the routine early post 1 h imaging in evaluating the atherosclerotic activity.

Imperatorin reduces the inflammatory response of atherosclerosis by regulating MAPKs signaling pathway in vivo and in vitro

Inflammation plays an important role in the process of atherosclerosis (AS). Inhibition of inflammation is an effective way to prevent AS. Imperatorin (IMP) is a kind of furan coumarin with various activities. In this study, the anti-inflammatory effect of IMP was explored in oxidized low-density lipoprotein (ox-LDL)-induced VSMCs and high fat diet (HFD)-induced ApoE^-/- mice. The results showed that IMP attenuated the elevation of TNF-α, IL-6, MCP-1 and NO induced by ox-LDL in supernatant of VSMCs. IMP has normalized the levels of serum lipids (TC, TG, LDL-C and HDL-C) and attenuated inflammatory cytokines in serum. IMP also improved pathological changes and lipid accumulation in aorta. Matrix metalloproteinase-2 (MMP-2) expression in aorta was down-regulated by IMP. IMP could inhibit the phosphorylation of MAPKs pathway in the aorta and VSMCs, resulting in a significant decrease in the contents of p-ERK 1/2, p-JNK and p-P38. Overall, IMP could exert anti-inflammatory effects in vivo and in vitro to interfere with AS.

An Allosteric Shift in CD11c Affinity Activates a Proatherogenic State in Arrested Intermediate Monocytes

Intermediate monocytes (iMo; CD14⁺CD16⁺) increase in number in the circulation of patients with unstable coronary artery disease (CAD), and their recruitment to inflamed arteries is implicated in events leading to mortality following MI. Monocyte recruitment to inflamed coronary arteries is initiated by high affinity β2-integrin (CD11c/CD18) that activates β1-integrin (VLA-4) to bind endothelial VCAM-1. How integrin binding under shear stress mechanosignals a functional shift in iMo toward an inflammatory phenotype associated with CAD progression is unknown. Whole blood samples from patients treated for symptomatic CAD including non-ST elevation MI, along with healthy age-matched subjects, were collected to assess chemokine and integrin receptor levels on monocytes. Recruitment on inflamed human aortic endothelium or rVCAM-1 under fluid shear stress was assessed using a microfluidic-based artery on a chip (A-Chip). Membrane upregulation of high affinity CD11c correlated with concomitant activation of VLA-4 within focal adhesive contacts was required for arrest and diapedesis across inflamed arterial endothelium to a greater extent in non-ST elevation MI compared with stable CAD patients. The subsequent conversion of CD11c from a high to low affinity state under fluid shear activated phospho-Syk- and ADAM17-mediated proteolytic cleavage of CD16. This marked the conversion of iMo to an inflammatory phenotype associated with nuclear translocation of NF-κB and production of IL-1β⁺ We conclude that CD11c functions as a mechanoregulator that activates an inflammatory state preferentially in a majority of iMo from cardiac patients but not healthy patients.

A Novel STAT3-Mediated GATA6 Pathway Contributes to tert-Butylhydroquinone- (tBHQ-) Protected TNFα-Activated Vascular Cell Adhesion Molecule 1 (VCAM-1) in Vascular Endothelium

The activation of vascular cell adhesion molecule 1 (VCAM-1) in vascular endothelial cells has been well considered implicating in the initiation and processing of atherosclerosis. Oxidative stress is mechanistically involved in proatherosclerotic cytokine-induced VCAM-1 activation. tert-Butylhydroquinone (tBHQ), a synthetic phenolic antioxidant used for preventing lipid peroxidation of food, possesses strongly antioxidant capacity against oxidative stress-induced dysfunction in various pathological process. Here, we investigated the protective role of tBHQ on tumor necrosis factor alpha- (TNFα-) induced VCAM-1 activation in both aortic endothelium of mice and cultured human vascular endothelial cells and uncovered its potential mechanisms. Our data showed that tBHQ treatment significantly reversed TNFα-induced activation of VCAM-1 at both transcriptional and protein levels. The mechanistic study revealed that inhibiting neither nuclear factor (erythroid-derived 2)-like 2 (Nrf2) nor autophagy blocked the beneficial role of tBHQ. Alternatively, tBHQ intervention markedly alleviated TNFα-increased GATA-binding protein 6 (GATA6) mRNA and protein expressions and its translocation into nucleus. Further investigation indicated that tBHQ-inhibited signal transducer and activator of transcription 3 (STAT3) but not mitogen-activated protein kinase (MAPK) pathway contributed to its protective role against VCAM-1 activation via regulating GATA6. Collectively, our data demonstrated that tBHQ prevented TNFα-activated VCAM-1 via a novel STAT3/GATA6-involved pathway. tBHQ could be a potential candidate for the prevention of proatherosclerotic cytokine-caused inflammatory response and further dysfunctions in vascular endothelium.

Inflammation in Coronary Atherosclerosis and Its Therapeutic Implications

Atherosclerotic coronary artery disease has a complex pathogenesis which extends beyond cholesterol intimal infiltration. It involves chronic inflammation of the coronary artery wall driven by systemic and local activation of both the adaptive and innate immune systems, which can ultimately result in the rupture or erosion of atherosclerotic plaque, leading to thrombosis and myocardial infarction (MI). Despite current best practice care, including the widespread use of cholesterol-lowering statins, atherothrombotic cardiovascular events recur at alarming rates post-MI. To a large extent, this reflects residual inflammation that is not adequately controlled by contemporary treatment. Consequently, there has been increasing interest in the pharmacological targeting of inflammation to improve outcomes in atherosclerotic cardiovascular disease. This has comprised both novel pathway-specific agents, most notably the anti-interleukin-1 beta monoclonal antibody, canakinumab, and the repurposing of established, broad-acting drugs, such as colchicine, that are already approved for the management of other inflammatory conditions. Here we discuss the importance of inflammation in mediating atherosclerosis and its complications and provide a timely update on "new" and "old" anti-inflammatory therapies currently being investigated to target it.

VCAM-1 Target in Non-Invasive Imaging for the Detection of Atherosclerotic Plaques

Simple Summary

Cardiovascular diseases are the first cause of morbimortality worldwide. They are mainly caused by atherosclerosis, with progressive plaque formation in the arterial wall. In this context, several imaging techniques have been developed to screen, detect and quantify atherosclerosis. Early screening improves primary prevention and promotes the prescription of adequate medication before adverse clinical events. In this review, we focus on the imaging of vascular cell adhesion molecule-1, an adhesion molecule involved in the first stages of the development of atherosclerosis. This molecule could therefore be a promising target to detect early atherosclerosis non-invasively. Potential clinical applications are critically discussed.

Abstract

Atherosclerosis is a progressive chronic arterial disease characterised by atheromatous plaque formation in the intima of the arterial wall. Several invasive and non-invasive imaging techniques have been developed to detect and characterise atherosclerosis in the vessel wall: anatomic/structural imaging, functional imaging and molecular imaging. In molecular imaging, vascular cell adhesion molecule-1 (VCAM-1) is a promising target for the non-invasive detection of atherosclerosis and for the assessment of novel antiatherogenic treatments. VCAM-1 is an adhesion molecule expressed on the activated endothelial surface that binds leucocyte ligands and therefore promotes leucocyte adhesion and transendothelial migration. Hence, for several years, there has been an increase in molecular imaging methods for detecting VCAM-1 in MRI, PET, SPECT, optical imaging and ultrasound. The use of microparticles of iron oxide (MPIO), ultrasmall superparamagnetic iron oxide (USPIO), microbubbles, echogenic immunoliposomes, peptides, nanobodies and other nanoparticles has been described. However, these approaches have been tested in animal models, and the remaining challenge is bench-to-bedside development and clinical applicability.

Health benefits of sesamin on cardiovascular disease and its associated risk factors

Sesamin, a major lignin isolated from sesame (Sesamum indicum) seeds and sesame oil, is known to possess antioxidant and anti-inflammatory properties. Several studies have revealed that oxidative stress and inflammation play a major role in a variety of cardiovascular diseases (CVDs). This comprehensive review summarizes the evidence on the effects of sesamin on CVD and its risk factors, principally due to its antioxidant properties. Specifically, this review highlights the mechanisms underlying the anti-hypertensive, anti-atherogenic, anti-thrombotic, anti-diabetic, and anti-obesity, lipolytic effects of sesamin both in vivo and in vitro, and identifies the signaling pathways targeted by sesamin and its metabolites. The data indicates that RAS/MAPK, PI3K/AKT, ERK1/2, p38, p53, IL-6, TNFα, and NF-κB signaling networks are all involved in moderating the various effects of sesamin on CVD and its risk factors. In conclusion, the experimental evidence suggesting that sesamin can reduce CVD risk is convincing. Thus, sesamin can be potentially useful as an adjuvant therapeutic agent to combat CVD and its multitude of risk factors.

Maternal exposure to soy diet reduces atheroma in hyperlipidemic F1 offspring mice by promoting macrophage and T cell anti-inflammatory responses

BACKGROUND AND AIMS

Maternal hypercholesterolemia has been implicated in earlier onset of atherosclerotic lesions in neonatal offspring. In this study, we investigated whether maternal exposure to soy protein isolate (SPI) diet attenuated the progression of atherosclerosis in F1 offspring.

METHOD

Pregnant apolipoprotein E knockout (Apoe^-/-) female mice were fed SPI diet until postnatal day 21 (PND21) of the offspring (SPI-offspring). SPI-offspring were switched at PND21 to casein (CAS) diet until PND140. Mice fed CAS throughout their lifetime (gestation to adulthood) were used as controls (CAS-offspring).

RESULTS

Atherosclerotic lesions in the aortic sinuses were reduced in SPI-offspring compared with CAS-offspring. Total serum cholesterol levels in CAS-offspring or dams were comparable to levels in their SPI-counterparts, suggesting that alternative mechanisms contributed to the athero-protective effect of maternal SPI diet. Aortic VCAM-1, MCP-1, and TNF-α mRNA and protein expression, and expression of macrophage pro-inflammatory cytokines was reduced in SPI-offspring. Interestingly, CD4⁺ T cells from SPI-offspring showed reduced IFN-γ expression (Th1), while the expression of IL-10 (Th2/Treg), and IL-13 (Th2) was increased. DNA methylation analyses revealed that anti-inflammatory T cell-associated Gata3 and Il13 promoter regions were hypomethylated in SPI-offspring. These findings suggest that anti-inflammatory macrophage and T cell response may have contributed to the athero-protective effect in SPI-offspring.

CONCLUSIONS

Our findings demonstrate that gestational and lactational soy diet exposure inhibits susceptibility to atherosclerotic lesion formation by promoting anti-inflammatory responses by macrophages and T cells.

Testosterone therapy in hypogonadal patients and the associated risks of cardiovascular events

Since the male secondary sex characters, libido and fertility are attributed to their major androgen hormone testosterone, the sub-optimum levels of testosterone in young adults may cause infertility and irregularities in their sexual behaviour. Such deficiency is often secondary to maladies involving testes, pituitary or hypothalamus that could be treated with an administration of exogenous testosterone. In the last few decades, the number of testosterone prescriptions has markedly increased to treat sub-optimal serum levels even though its administration in such conditions is not yet approved. On account of its associated cardiovascular hazards, the food and drug authority in the United States has issued safety alerts on testosterone replacement therapy (TRT). Owing to a great degree of conflict among their findings, the published clinical trials seem struggling in presenting a decisive opinion on the matter. Hence, the clinicians remain uncertain about the possible cardiovascular adversities while prescribing TRT in hypogonadal men. The uncertainty escalates even further while prescribing such therapy in older men with a previous history of cardiovascular ailments. In the current review, we analysed the pre-clinical and clinical studies to evaluate the physiological impact of testosterone on cardiovascular and related parameters. We have enlisted studies on the association of cardiovascular health and endogenous testosterone levels with a comprehensive analysis of epidemiological studies, clinical trials, and meta-analyses on the cardiovascular risk of TRT. The review is aimed to assist clinicians in making smart decisions regarding TRT in their patients.

Hospitalization With Major Infection and Incidence of End-Stage Renal Disease: The Atherosclerosis Risk in Communities (ARIC) Study

OBJECTIVE

To evaluate whether the incidence of infectious diseases increases the long-term risk for incident end-stage renal disease (ESRD) in the general population.

PATIENTS AND METHODS

In 10,290 participants of the Atherosclerosis Risk in Communities Study who attended visit 4 (1996-1998), we evaluated the association of incident hospitalization with major infections (pneumonia, urinary tract infection, bloodstream infection, and cellulitis and osteomyelitis) with subsequent risk for ESRD through September 30, 2015. Hospitalization with major infection was entered into multivariable Cox models as a time-varying exposure to estimate the hazard ratios.

RESULTS

Mean age was 63 years, and of 10,290 individuals, 56% (n=5781) were women, 22% (n=2252) were black, and 7% (n=666) had an estimated glomerular filtration rate less than 60 mL/min/1.73 m2. During a median follow-up of 17.4 years, there were 2642 incident hospitalizations with major infection and 281 cases of ESRD (132 cases after hospitalization with major infection). The risk for ESRD was higher following major infection compared with while free of major infection (crude incidence rate, 10.9 vs 1.0 per 1000 person-years). In multivariable time-varying Cox analysis, hospitalization with major infection was associated with a 3.3-fold increased risk for ESRD (hazard ratio, 3.34; 95% CI, 2.56-4.37). The association was similar across pneumonia, urinary tract infection, bloodstream infection, and cellulitis and osteomyelitis, and remained significant across subgroups of age, sex, race, diabetes, history of cardiovascular disease, and chronic kidney disease.

CONCLUSION

Hospitalization with major infection was independently and robustly associated with subsequent risk for ESRD. Whether preventive approaches against infection have beneficial effects on kidney outcomes may deserve future investigations.

Mixed Lineage Kinase Domain-Like Protein Promotes Human Monocyte Cell Adhesion to Human Umbilical Vein Endothelial Cells Via Upregulation of Intercellular Adhesion Molecule-1 Expression

BACKGROUND Atherosclerosis is a progressive inflammatory disease that involves a variety of inflammatory and proinflammatory factors, including intercellular adhesion molecule (ICAM)-1. ICAM-1 plays an important role in atherosclerosis by promoting cell adhesion. Mixed lineage kinase domain-like (MLKL), a critical regulator of necroptotic cell death, is indicated to play an important role in atherosclerosis. This study investigated the effects of MLKL on ICAM-1 expression and cell adhesion, thus providing a new direction for the research of atherosclerosis pathogenesis. MATERIAL AND METHODS siRNA-MLKL and pcDNA-MLKL were designed, and the expression of MLKL and ICAM-1 were estimated by real-time polymerase chain reaction at the mRNA level and Western blotting at the protein level. The adhesion of human monocyte cells (THP-1) to human umbilical vein endothelial cells (HUVECs) was examined under immunofluorescence microscopy, and the ability of cell adhesion was evaluated by ImageJ software. RESULTS Overexpression of MLKL greatly enhanced ICAM-1 expression in HUVECs and the adherence of THP-1 cells to HUVECs. Knockdown of MLKL by siRNA dramatically inhibited the expression of ICAM-1 and the adherence of THP-1 cells to HUVECs. MLKL could promote THP-1 adhesion to HUVECs by activating ICAM-1 expression in HUVECs. CONCLUSIONS MLKL can promote THP-1 cell adhesion to HUVECs through up-regulation of ICAM-1 expression in HUVECs. Thus, MLKL might be a useful target for reducing adhesion of monocytes to endothelial cells and atherosclerosis.

Late-onset hypogonadism: Reductio ad absurdum of the cardiovascular risk-benefit of testosterone replacement therapy

BACKGROUND

Low testosterone (T) level is considered a marker of poor cardiovascular health. Ten years ago, the Testosterone in Older Men with Mobility Limitations (TOM) trial was discontinued due to a higher number of adverse events in men receiving T compared with placebo. Since then, several studies have investigated the risks of T replacement therapy (TRT) in late-onset hypogonadism (LOH).

OBJECTIVE

To review the mechanism by which TRT could damage the cardiovascular system.

MATERIALS AND METHODS

Comprehensive literature search of recent clinical and experimental studies.

RESULTS

The mechanisms of T-mediated coronary vasodilation were reviewed with emphasis on calcium-activated and ATP-sensitive potassium ion channels. We showed how T regulates endothelial nitric oxide synthase (eNOS) and phosphoinositide 3-kinase/protein kinase B/eNOS signaling pathways in vessel walls and its direct effects on cardiomyocytes via β1-adrenergic and ryanodine receptors and provided data on myocardial infarction and heart failure. Vascular smooth muscle senescence could be explained by the modulation of growth factors, matrix metalloproteinase-2, and angiotensin II by T. Furthermore, leukocyte trafficking, facilitated by changes in TNF-α, could explain some of the effects of T on atheromatous plaques. Conflicting data on prothrombotic risk linked to platelet aggregation inhibition via NO-triggered arachidonate synthesis or increased aggregability due to enhanced thromboxane A in human platelets provide evidence regarding the hypotheses on plaque maturation and rupture risk. The effects of T on cardiac electrophysiology and oxygen delivery were also reviewed.

DISCUSSION

The effects of TRT on the cardiovascular system are complex. Although molecular studies suggest a potential benefit, several clinical observations reveal neutral or occasionally detrimental effects, mostly due to confounding factors.

CONCLUSIONS

Attempts to demonstrate that TRT damages the cardiovascular system via systematic analysis of the putative mechanisms led to the contradiction of the initial hypothesis. Current evidence indicates that TRT is safe once other comorbidities are addressed.

Preoperative soluble VCAM-1 contributes to predict late mortality after coronary artery surgery

Background

Soluble vascular cell adhesion molecule‐1 has been associated with long‐term cardiovascular mortality in patients with stable coronary artery disease and to the development of new atrial fibrillation in subjects with cardiovascular risk factors but no evidence of cardiac disease.

Hypothesis

Preoperative soluble vascular cell adhesion molecule‐1 predicts the risk of future all‐cause death and cardiovascular death among patients submitted to elective coronary artery bypass surgery.

Methods

From a cohort of 312 patients who underwent elective coronary artery bypass surgery prospectively followed for a median of 6.7 years, we evaluated the prognostic role of preoperative soluble vascular cell adhesion molecule‐1, inflammatory markers, CHA2DS2‐VASc score and development of postoperative atrial fibrillation (POAF). Univariable and multivariable Cox regression analyses were performed to establish an association of these parameters with long term all‐cause death and cardiovascular death.

Results

During 2112 person‐years of follow‐up, we observed 41 deaths, 10 were cardiovascular deaths. Independently increased levels of preoperative soluble vascular cell adhesion molecule‐1, POAF, and CHA2DS2‐VASc score were associated with all‐cause mortality. After multivariate adjustment, elevated preoperative soluble vascular cell adhesion molecule‐1 and POAF were the only independent predictors of all‐cause death. Also, preoperative soluble vascular cell adhesion molecule‐1, POAF, and CHA2DS2‐VASc score resulted in being independent predictors of cardiovascular mortality.

Conclusions

Increased circulating levels of preoperative soluble vascular cell adhesion molecule‐1, together with POAF and CHA2DS2‐VASc score, were significantly associated with future all‐cause death and cardiovascular death among patients submitted to coronary artery bypass surgery.

Serum discrimination and phenotype assessment of coronary artery disease patents with and without type 2 diabetes prior to coronary artery bypass graft surgery

Diabetes Mellitus (DM) accelerates coronary artery disease (CAD) and atherosclerosis, the causes of most heart attacks. The biomolecules involved in these inter-related disease processes are not well understood. This study analyzes biomolecules in the sera of patients with CAD, with and without type (T) 2DM, who are about to undergo coronary artery bypass graft (CABG) surgery. The goal is to develop methodology to help identify and monitor CAD patients with and without T2DM, in order to better understand these phenotypes and to glean relationships through analysis of serum biomolecules. Aorta, fat, muscle, and vein tissues from CAD T2DM patients display diabetic-related histologic changes (e.g., lipid accumulation, fibrosis, loss of cellularity) when compared to non-diabetic CAD patients. The patient discriminatory methodology utilized is serum biomolecule mass profiling. This mass spectrometry (MS) approach is able to distinguish the sera of a group of CAD patients from controls (p value 10⁻¹⁵), with the CAD group containing both T2DM and non-diabetic patients. This result indicates the T2DM phenotype does not interfere appreciably with the CAD determination versus control individuals. Sera from a group of T2DM CAD patients however are distinguishable from non-T2DM CAD patients (p value 10⁻⁸), indicating it may be possible to examine the T2DM phenotype within the CAD disease state with this MS methodology. The same serum samples used in the CAD T2DM versus non-T2DM binary group comparison were subjected to MS/MS peptide structure analysis to help identify potential biochemical and phenotypic changes associated with CAD and T2DM. Such peptide/protein identifications could lead to improved understanding of underlying mechanisms, additional biomarkers for discriminating and monitoring these disease conditions, and potential therapeutic targets. Bioinformatics/systems biology analysis of the peptide/protein changes associated with CAD and T2DM suggested cell pathways/systems affected include atherosclerosis, DM, fibrosis, lipogenesis, loss of cellularity (apoptosis), and inflammation.

Epsin-mediated degradation of IP3R1 fuels atherosclerosis

The epsin family of endocytic adapter proteins are widely expressed, and interact with both proteins and lipids to regulate a variety of cell functions. However, the role of epsins in atherosclerosis is poorly understood. Here, we show that deletion of endothelial epsin proteins reduces inflammation and attenuates atherosclerosis using both cell culture and mouse models of this disease. In atherogenic cholesterol-treated murine aortic endothelial cells, epsins interact with the ubiquitinated endoplasmic reticulum protein inositol 1,4,5-trisphosphate receptor type 1 (IP3R1), which triggers proteasomal degradation of this calcium release channel. Epsins potentiate its degradation via this interaction. Genetic reduction of endothelial IP3R1 accelerates atherosclerosis, whereas deletion of endothelial epsins stabilizes IP3R1 and mitigates inflammation. Reduction of IP3R1 in epsin-deficient mice restores atherosclerotic progression. Taken together, epsin-mediated degradation of IP3R1 represents a previously undiscovered biological role for epsin proteins and may provide new therapeutic targets for the treatment of atherosclerosis and other diseases.

Fluid shear stress modulates endothelial inflammation by targeting LIMS2

Mechanosensitive genes regulate multiple cardiovascular pathophysiological processes and disorders; however, the role of flow-sensitive genes in atherosclerosis is still unknown. In this study, we identify LIM Zinc Finger Domain Containing 2 (LIMS2) that acts as a mechanosensitive gene downregulated by disturbed flow (d-flow) both in human endothelial cells (ECs) in vitro and in mice in vivo. Mechanistically, d-flow suppresses LIMS2 expression, which leads to endothelial inflammation by upregulating typical inflammatory factors, VCAM-1, and ICAM-1 in human ECs. The findings indicate that LIMS2, the new flow-sensitive gene, may help us to find a new insight to explain how d-flow caused endothelial inflammation and provide a new therapeutic approach for atherosclerosis in the future.