Raised soluble P-selectin moderately accelerates atherosclerotic plaque progression

Multiple exposures to low-dose ionizing radiation induced the initiation and progression of pro-atherosclerotic phenotypes in mice and vascular endothelial cell damage

OBJECTIVE

This study aimed to investigate the effects of low-dose radiation on the abdominal aorta of mice and vascular endothelial cells.

METHODS

Wild-type and tumor-bearing mice were exposed to 15 sessions of low-dose irradiation, resulting in cumulative radiation doses of 187.5, 375, and 750 mGy. The effect on the cardiovascular system was assessed. Immunohistochemistry analyzed protein expressions of PAPP-A, CD62, P65, and COX-2 in the abdominal aorta. Microarray technology, Gene Ontology analysis, and pathway enrichment analysis evaluated gene expression changes in endothelial cells exposed to 375 mGy X-ray. Cell viability was assessed using the Cell Counting Kit 8 assay. Immunofluorescence staining measured γ-H2AX levels, and real-time polymerase chain reaction quantified mRNA levels of interleukin-6 (IL-6), ICAM-1, and Cx43.

RESULTS

Hematoxylin and eosin staining revealed thickening of the inner membranes and irregular arrangement of smooth muscle cells in the media membrane at 375 and 750 mGy. Inflammation was observed in the inner membranes at 750 mGy, with a clear inflammatory response in the hearts of tumor-bearing mice. Immunohistochemistry indicated increased levels of PAPP-A, P65, and COX-2 post-irradiation. Microarray analysis showed 425 up-regulated and 235 down-regulated genes, associated with processes like endothelial cell-cell adhesion, IL-6, and NF-κB signaling. Cell Counting Kit 8 assay results indicated inhibited viability at 750 mGy in EA.hy926 cells. Immunofluorescence staining demonstrated a dose-dependent increase in γ-H2AX foci. Reverse transcription quantitative PCR results showed increased expression of IL6, ICAM-1, and Cx43 in EA.hy926 cells post 750 mGy X-ray exposure.

CONCLUSION

Repeated low-dose ionizing radiation exposures triggered the development of pro-atherosclerotic phenotypes in mice and damage to vascular endothelial cells.

Uncovering the shared molecule and mechanism between ulcerative colitis and atherosclerosis: an integrative genomic analysis

Background

Ulcerative colitis (UC) and atherosclerosis (AS) are closely related. However, the pathologic mechanisms underlying the co-occurrence of UC and AS are not well understood.

Objects

To reveal the hub molecule and mechanism involved in the co-occurrence of UC and AS.

Methods

Differentially expressed genes (DEGs) of UC and AS were obtained, and the shared DEGs of UC and AS were explored for biological function. Next, the hub genes were explored using the cytoHubba plugin. The predictive ability of the hub genes was measured by constructing the receiver operating characteristic curve. Analyses of immune infiltration and the single-gene gene set enrichment analysis (GSEA) for the hub genes were further carried out.

Results

Identification of 59 DEGs (55 were upregulated and four were downregulated) shared by both UC and AS was performed. Enriched pathways of the shared DEGs were mainly related to immunity and inflammation. Protein tyrosine phosphatase, receptor type, C (PTPRC) was identified as the hub crosstalk gene for the comorbidity of UC and AS. The upregulation of PTPRC was correlated with mast cells resting, T cells CD4 memory resting, macrophages M0, and macrophages M1. Pathways of immune and inflammatory processes, including NF-kappa B, viral protein interaction with cytokine and cytokine receptor, and cytokine-cytokine receptor interaction, were significantly correlated with high expression of PTPRC in UC and AS.

Conclusion

At the transcriptional level, our study reveals that imbalanced inflammatory and immune responses are the key pathological mechanisms underlying the comorbidity of UC and AS and that PTPRC is a key biomarker for the comorbidity of UC and AS.

The impact of SELP gene Thr715Pro polymorphism on sP-selectin level and association with cardiovascular disease in Saudi diabetic patients: A cross-sectional case-control study

Background

Cardiovascular diseases (CVD) are leading cause of mortality in patients with type 2 diabetes mellitus (T2DM). Increased soluble sP-selectin and 715Thr > Pro polymorphism were studied in CVD and T2DM, but association between them hasn't been explored in Saudi Arabia. We aimed to assess sP-selectin levels in T2DM and T2DM-associated CVD patients in comparison to healthy control cohort. Also, we sought to investigate relationship between Thr715Pro polymorphism and sP-selectin levels and disease state.

Methods

This is a cross-sectional case-control study. sP-selectin level (measured by Enzyme-linked immunosorbent assay) and prevalence of Thr715Pro polymorphism (assessed by Sanger sequencing) were investigated in 136 Saudi participants. The study comprised 3 groups: group1 included 41 T2DM patients; group 2 (48 T2DM patients with CVD), and group 3 (47 healthy controls).

Results

sP-selectin levels were significantly higher in diabetics and diabetics + CVD groups as compared to the corresponding control. In addition, results showed that the prevalence of 715Thr > Pro polymorphism is 11.75 % in the study population amongst the three study groups (9.55 % Thr/Pro, and 2.2 % Pro/Pro). No statistical difference was found between sP-selectin levels in subject carrying the wildtype genotype of this polymorphism and these who carry the mutant gene. There could be an association between this polymorphism and T2DM, whilst the polymorphism may protect diabetic patients from having CVD. However, odds ratio is not statistically significant in both cases.

Conclusion

Our study supports the previous researches' results that Thr715Pro is neither influencing the sP-selectin level nor the risk of CVD in T2DM patients.

Study on the Active Constituents and Molecular Mechanism of Zhishi Xiebai Guizhi Decoction in the Treatment of CHD Based on UPLC-UESI-Q Exactive Focus, Gene Expression Profiling, Network Pharmacology, and Experimental Validation

As one of the most common clinical cardiovascular diseases (CVDs), coronary heart disease (CHD) is the most common cause of death in the world. It has been confirmed that Zhishi Xiebai Guizhi decoction (ZXGD), a classical prescription of the traditional Chinese medicine (TCM), has achieved certain effects in the treatment of CHD; however, the mechanism still remains controversial. In this paper, an integrated approach, including UPLC-UESI-Q Exactive Focus, gene expression profiling, network pharmacology, and experimental validation, was introduced to systematically investigate the mechanism of ZXGD in the treatment of CHD. First, UPLC-UESI-Q Exactive Focus was applied to identify the chemical compounds of ZXGD. Then, the targets of the components for ZXGD were predicted by MedChem Studio software embed in the integrative pharmacology-based research platform of TCM, and the differentially expressed genes (DEGs) of CHD were obtained by gene expression profiling in gene expression omnibus database. The common genes of the above two genes were obtained by Venn analysis as the targets of GXGD in treatment with CHD. Third, the core targets were screened out by protein-protein interaction network analysis, and the kyoto encyclopedia of genes and genomes pathway enrichment analysis was performed by the database for annotation, visualization, and integrated discovery bioinformatics resources. After that, the formula-herb-compound-target-pathway network was constructed to explore the mechanism of ZXGD in the treatment of CHD. Finally, molecular docking and the vitro experiment were carried out to validate some key targets. As a result, a total of 39 compounds, 12 core targets, and 4 pathways contributed to ZXGD for the treatment of CHD. This study preliminarily provided a foundation for the study on the mechanism against CHD for ZXGD and may be a reference for the compatibility mechanism and the extended application of TCM compound prescription.

Differential and targeted vesiculation: pathologic cellular responses to elevated arterial pressure

Extracellular vesicles are small membrane-enclosed particles released during cell activation or injury. They have been investigated for several decades and found to be secreted in various diseases. Their pathogenic role is further supported by the presence of several important molecules among their cargo, including proteins, lipids, and nucleic acids. Many studies have reported enhanced and targeted extracellular vesicle biogenesis in diseases that involve chronic or transient elevation of arterial pressure resulting in endothelial dysfunction, within either the general circulatory system or specific local vascular beds. In addition, several associated pathologic processes have been studied and reported. However, the role of elevated pressure as a common pathogenic trigger across vascular domains and disease chronicity has not been previously described. This review will therefore summarize our current knowledge of the differential and targeted biogenesis of extracellular vesicles in major diseases that are characterized by elevated arterial pressure leading to endothelial dysfunction and propose a unified theory of pressure-induced extracellular vesicle-mediated pathogenesis.

Synopsis of Biomarkers of Atheromatous Plaque Formation, Rupture and Thrombosis in the Diagnosis of Acute Coronary Syndromes

Acute coronary syndrome is the main cause of mortality and morbidity worldwide and early diagnosis is a challenge for clinicians. Though cardiac Troponin, the most commonly used biomarker, is the gold standard for myocardial necrosis, it is blind for ischemia without necrosis. Therefore, ideal biomarkers are essential in the care of patients presenting with symptoms suggestive of cardiac ischemia. The ideal biomarker or group of biomarkers of atheromatous plaque formation, rupture and thrombosis for timely and accurate diagnosis of acute coronary syndrome is a current need. Therefore, we discuss the existing understanding and future of biomarkers of atheromatous plaque formation, rupture and thrombosis of acute coronary syndrome in this review. Keywords were searched from Medline, ISI, IBSS and Google Scholar databases. Further, the authors conducted a manual search of other relevant journals and reference lists of primary articles. The development of high-sensitivity troponin assays facilitates earlier exclusion of acute coronary syndrome, contributing to a reduced length of stay at the emergency department, and earlier treatment resulting in better outcomes. Although researchers have investigated biomarkers of atheromatous plaque formation, rupture and thrombosis to help early diagnosis of cardiac ischemia, most of them necessitate validation from further analysis. Among these biomarkers, pregnancy-associated plasma protein-A, intercellular adhesion molecule-1, and endothelial cell-specific molecule- 1(endocan) have shown promising results in the early diagnosis of acute coronary syndrome but need further evaluation. However, the use of a combination of biomarkers representing varying pathophysiological mechanisms of cardiac ischemia will support risk assessment, diagnosis and prognosis in these patients and this is the way forward.

The Role of ROCK in Platelet-Monocyte Collaborative Induction of Thromboinflammation during Acute Coronary Syndrome

BACKGROUND

 Arterial thrombosis is initiated by atherosclerotic plaque damage, prothrombotic material release and platelet aggregation. Platelets are primary mediators involved in thrombosis and cooperate with vascular and immune cells.

OBJECTIVE

 Herein, we investigated how activated platelets interacted with monocytes in atherothrombosis.

METHODS AND RESULTS

 We collected patients' blood from coronary arteries during percutaneous coronary intervention and measured platelet activity. Platelets from coronary arteries had higher pseudopodium expression and activity in patients with acute coronary syndrome (ACS). Ribosome profiling of platelets from coronary blood mapped a vigorous upregulation of Rho GTPases and their downstream effectors. RhoA activated downstream Rho-associated coiled-coil containing protein kinase (ROCK), and ROCK increased surface P-selectin in coronary blood platelets. The interaction between platelets and monocytes was observed in vitro, and was found in ruptured coronary plaques of ACS. Further we found that activated platelets promoted monocytes transmigration, which could be suppressed in the presence of ROCK inhibitors. The increased surface P-selectin on thrombin-induced platelets interacted with monocytes to upregulate monocyte chemokine receptor 2 (CCR2) expression via the ROCK pathway. The expression of CCR2 was higher in monocyte-platelet aggregates than in monocytes without platelets. Finally, using the Asian Screening Array BeadChip, we identified single-nucleotide polymorphism (SNP) associated with cardiovascular events. Notably, patients having homozygous major alleles of the RHOA SNP rs11706370 presented with higher risks of cardiovascular events.

CONCLUSION

 Through ROCK-activated cytoskeleton remodeling and P-selectin expression, platelets were recruited and interacted synergistically with high CCR2-expressing monocytes to induce thromboinflammation in atherothrombosis.

Bioinformatics analysis of vascular RNA-seq data revealed hub genes and pathways in a novel Tibetan minipig atherosclerosis model induced by a high fat/cholesterol diet

BACKGROUND

Atherosclerosis is a major contributor to cardiovascular events, however, its molecular mechanism remains poorly known. Animal models of atherosclerosis can be a valuable tool to provide insights into the etiology, pathophysiology, and complications of atherosclerosis. In particular, Tibetan minipigs are a feasible model for studying diet-related metabolic and atherosclerotic diseases.

METHODS

We used vascular transcriptomics to identify differentially expressed genes (DEGs) in high fat/cholesterol (HFC) diet-fed Tibetan minipig atherosclerosis models, analyzed the DEGs gene ontology (GO) terms, pathways and protein-protein interactions (PPI) networks, and identified hub genes and key modules using molecular complex detection (MCODE), Centiscape and CytoHubba plugin. The identified genes were validated using the human carotid atherosclerosis database (GSEA 43292) and RT-PCR methods.

RESULTS

Our results showed that minipigs displayed obvious dyslipidemia, oxidative stress, inflammatory response, atherosclerotic plaques, as well as increased low-density lipoprotein (LDL) and leukocyte recruitment after 24 weeks of HFC diet feeding compared to those under a regular diet. Our RNA-seq results revealed 1716 DEGs in the atherosclerotic/NC group, of which 1468 genes were up-regulated and 248 genes were down-regulated. Functional enrichment analysis of DEGs showed that the HFC diet-induced changes are related to vascular immune-inflammatory responses, lipid metabolism and muscle contraction, indicating that hypercholesterolemia caused by HFC diet can activate innate and adaptive immune responses to drive atherosclerosis development. Furthermore, we identified four modules from the major PPI network, which are implicated in cell chemotaxis, myeloid leukocyte activation, cytokine production, and lymphocyte activation. Fifteen hub genes were discovered, including TNF, PTPRC, ITGB2, ITGAM, VCAM1, CXCR4, TYROBP, TLR4, LCP2, C5AR1, CD86, MMP9, PTPN6, C3, and CXCL10, as well as two transcription factors (TF), i.e. NF-ĸB1 and SPI1. These results are consistent with the expression patterns in human carotid plaque and were validated by RT-PCR.

CONCLUSIONS

The identified DEGs and their enriched pathways provide references for the development and progression mechanism of Tibetan minipig atherosclerosis model induced by the HFC diet.

Correlations of inhaled NO with the cTnI levels and the plasma clotting factor in rabbits with acute massive pulmonary embolism

PURPOSE

To investigate the correlation of inhaled nitric oxide (NO) on plasma levels of cardiac troponin I (cTnI) and von Willebrand factor (vWF), glycoprotein (GP) IIb/IIIa, granule membrane protein 140 (GMP-140) in rabbits with acute massive pulmonary embolism (PE).

METHODS

Thirty apanese white rabbits were divided into 3 groups, thrombus were injected in model group (n = 10), NO were inhalated for 24 h after massive PE in NO group (n = 10), saline were injected in control group (n = 10). The concentrations of vWF, GP IIb/IIIa, GMP-140 and cTnI were tested at 4, 8, 12, 16, 20, and 24 h, Correlation analyses were conducted between cTnI and vWF, GP IIb/IIIa, and GMP-140 by Pearson's correlation.

RESULTS

The concentration of cTnI and vWF, GP IIb/IIIa, and GMP-140 was increased in the model group, compared to control group. In the inhaled group, the concentrations of cTnI, vWF, GP IIb/IIIa, and GMP-140 were reduced compared to model group. There was a positive correlation between cTnI and vWF, GP IIb/IIIa, and GMP-140.

CONCLUSION

Inhaled nitric oxide can lead to a decrease in levels of cardiac troponin I, von Willebrand factor, glycoprotein, and granule membrane protein 140, after an established myocardial damage, provoked by acute massive pulmonary embolism.

Guanosine exerts antiplatelet and antithrombotic properties through an adenosine-related cAMP-PKA signaling

BACKGROUND

Guanosine is a natural product and an endogenous nucleoside that has shown to increase during myocardial ischemia. Platelets are critically involved in ischemic coronary events. It remains unknown, however, whether guanosine may affect platelet activation and function. We sought to investigate the potential antiplatelet and antithrombotic properties of guanosine and decipher the mechanisms behind.

METHODS

We firstly assessed the effects of guanosine on platelet activation/aggregation upon stimulation with several platelet agonists including adenosine diphosphate (ADP), collagen, arachidonic acid (AA), and TRAP-6. Guanosine antithrombotic potential was also evaluated both in vitro (Badimon perfusion chamber) and in vivo (murine model). In addition we assessed any potential effect on bleeding. At a mechanistic level we determined the release of thromboxane B2, intraplatelet cAMP levels, the binding affinity on platelet membrane, and the activation/phosphorylation of protein kinase A (PKA), phospholipase C (PLC) and PKC.

RESULTS

Guanosine markedly inhibited platelet activation/aggregation-challenged by ADP and, although to a lesser extent, also reduced platelet aggregation challenged by collagen, AA and TRAP-6. Guanosine significantly reduced thrombus formation both in vitro and in vivo without significantly affects bleeding. Guanosine antiplatelet effects were associated with the activation of the cAMP/PKA signaling pathway, and a reduction in thromboxane B2 levels and PLC and PKC phosphorylation. The platelet aggregation and binding affinity assays revealed that guanosine effects on platelets were mediated by adenosine.

CONCLUSION

Guanosine effectively reduces ADP-induced platelet aggregation and limits thrombotic risk. These antithrombotic properties are associated with the activation of the cAMP/PKA signaling pathway.

Increased Soluble VCAM-1 and Normal P-Selectin in Cystic Fibrosis: a Cross-Sectional Study

Purpose

As life expectancy in cystic fibrosis (CF) increases, questions regarding its potential impact on cardiovascular health arise. Soluble vascular cell adhesion molecule 1 (sVCAM-1), P-selectin (sP-selectin) are proposed as biomarkers of cardiovascular disease. We aimed to: compare their concentrations in clinically stable CF patients and healthy subjects (HS) and verify whether they independently correlate with CF characteristics.

Methods

Serum sVCAM-1 and sP-selectin levels were measured using ELISA. CF was characterized using: forced expiratory volume in 1 s, exocrine pancreatic and CF-related liver disease status, Pseudomonas aeruginosa colonization, serum high-sensitivity C-reactive protein, and body mass index (BMI). CFTR genotypes were classified as severe (classes I and II) or other.

Results

108 CF patients and 51 healthy subjects volunteered for the study. In the CF group BMI was lower (median [IQR]: 20.5 kg/m² [18.4–22.2] vs. 21.6 kg/m² [19.9–23.4], p = 0.02) and hsCRP levels were higher (3.6 mg/L [1.1–7.1] vs. 0.5 mg/dL [0.3–1.0], p < 10⁻¹⁰). While sVCAM-1 concentrations were greater in CF patients (1018 ng/mL [851–1279] vs. 861 ng/mL [806–979], p < 10⁻⁴), sP-selectin levels did not differ (155 ng/mL [129–188] vs. 156 ng/mL [144–177], p = 0.48). None of the multivariable regression models was valid for the prediction of sVCAM-1 and sP-selectin in CF.

Conclusions

We found higher sVCAM-1 concentrations in CF patients than in healthy subjects, which were not explained by CF characteristics. Further research is required to check whether sVCAM-1 is a marker of microangiopathy in CF.

Circulating soluble P-selectin must dimerize to promote inflammation and coagulation in mice

Leukocyte adhesion to P-selectin on activated platelets and endothelial cells induces shedding of the P-selectin ectodomain into the circulation. Plasma soluble P-selectin (sP-selectin) is elevated threefold to fourfold in patients with cardiovascular disease. Circulating sP-selectin is thought to trigger signaling in leukocytes that directly contributes to inflammation and thrombosis. However, sP-selectin likely circulates as a monomer, and in vitro studies suggest that sP-selectin must dimerize to induce signaling in leukocytes. To address this discrepancy, we expressed the entire ectodomain of mouse P-selectin as a monomer (sP-selectin) or as a disulfide-linked dimer fused to the Fc portion of mouse immunoglobulin G (sP-selectin-Fc). Dimeric sP-selectin-Fc, but not monomeric sP-selectin, triggered integrin-dependent adhesion of mouse leukocytes in vitro. Antibody-induced oligomerization of sP-selectin or sP-selectin-Fc was required to trigger formation of neutrophil extracellular traps. Injecting sP-selectin-Fc, but not sP-selectin, into mice augmented integrin-dependent adhesion of neutrophils in venules, generated tissue factor-bearing microparticles, shortened plasma-clotting times, and increased thrombus frequency in the inferior vena cava. Furthermore, transgenic mice that overexpressed monomeric sP-selectin did not exhibit increased inflammation or thrombosis. We conclude that elevated plasma sP-selectin is a consequence rather than a cause of cardiovascular disease.

Disordered haematopoiesis and athero-thrombosis

Atherosclerosis, the major underlying cause of cardiovascular disease, is characterized by a lipid-driven infiltration of inflammatory cells in large and medium arteries. Increased production and activation of monocytes, neutrophils, and platelets, driven by hypercholesterolaemia and defective high-density lipoproteins-mediated cholesterol efflux, tissue necrosis and cytokine production after myocardial infarction, or metabolic abnormalities associated with diabetes, contribute to atherogenesis and athero-thrombosis. This suggests that in addition to traditional approaches of low-density lipoproteins lowering and anti-platelet drugs, therapies directed at abnormal haematopoiesis, including anti-inflammatory agents, drugs that suppress myelopoiesis, and excessive platelet production, rHDL infusions and anti-obesity and anti-diabetic agents, may help to prevent athero-thrombosis.

Compound 21, a selective agonist of angiotensin AT2 receptors, prevents endothelial inflammation and leukocyte adhesion in vitro and in vivo

BACKGROUND AND PURPOSE

Angiotensin AT2 receptors are upregulated in disease states such as atherosclerosis and blockade of the AT2 receptors exacerbates plaque formation. Direct stimulation of these receptors is anti-atherogenic but the mechanisms and pathways involved remain unknown. We examined the effect of direct AT2 receptor stimulation with Compound 21 (C21) on the leukocyte adhesion cascade in vitro, right through to plaque formation in vivo.

EXPERIMENTAL APPROACH

Effects of C21 on TNFα-induced inflammation were assessed in human umbilical vein endothelial cells (HUVECs), activation of monocytes, polarisation of monocyte-derived macrophages and in intact mouse aortae.

KEY RESULTS

C21 attenuated TNFα-induced: monocyte adhesion to cultured HUVECs, adhesion molecule expression and abolished TNFα-induced ROS production. TNFα-induced NFκB translocation from the cytoplasm to the nucleus, essential for cytokine production, was prevented by C21. C21 did not influence monocyte activation or macrophage polarisation but did reduce TNFα and IL-6 mRNA expression in M1 macrophages. The anti-inflammatory effects of C21 were abolished by an AT2 receptor antagonist confirming that the effects of C21 were AT2 receptor-mediated. Also, leukocyte adhesion and cytokine gene expression, induced by high-fat diet (HFD), was attenuated in ApoE(-/-) mice treated with C21. Plaque size and stability were improved with C21 treatment with increased smooth muscle cell composition and decreased lipid size, compared with HFD-saline treated mice.

CONCLUSION AND IMPLICATIONS

C21 prevented TNFα-induced and HFD-induced vascular inflammation in vitro and in vivo. Our data provide strong evidence that the anti-atherosclerotic actions of C21 were due to vascular anti-inflammatory effects, mediated by AT2 receptors.

Circulating CD62P small microparticles levels are increased in hypertension

The study aims to find a new biomarker in hypertension. Our study is the first time to demonstrate that the CD62P small microparticle (diameter is <0.5 um) was a new microparticle population and a new biomarker in hypertension.