Arteriosclerosis, Thrombosis, and Vascular Biology最新文献

Background: Pulmonary hypertension is a devastating vascular disorder characterized by extensive pulmonary vascular remodeling, ultimately leading to right ventricular failure and death. Activation of PDGF (platelet-derived growth factor) signaling promotes the hyperproliferation of pulmonary arterial smooth muscle cells (PASMCs), thus contributing to the pulmonary vascular remodeling. However, the molecular mechanisms that govern hyperproliferation of PASMCs induced by PDGF remain largely unknown, including the contribution of long noncoding RNAs (lncRNAs). In this study, we aimed to identify a novel lncRNA regulated by PDGF implicated in PASMC proliferation in pulmonary vascular remodeling.

Methods: RNA-sequencing analysis was conducted to identify a novel lncRNA named vessel-enriched lncRNA regulated by PDGF-BB (platelet-derived growth factor-BB; VELRP). Functional investigations of VELRP were performed using knockdown and overexpression strategies along with RNA sequencing. Validation of the function and potential mechanisms of VELRP was performed through Western blot, RNA immunoprecipitation, and chromatin immunoprecipitation assays.

Results: We identified a novel vessel-enriched lncRNA with an increased response to PDGF-BB stimulus. VELRP was identified as an evolutionarily conserved RNA molecule. Modulation of VELRP in PASMCs significantly altered cell proliferation. Mechanistically, VELRP enhances trimethylation of H3K4 (histone H3 lysine 4) by interacting with WDR5 (WD repeat-containing protein 5), leading to increased expression of CDK (cyclin-dependent kinase) 1, CDK2, and CDK4 and consequent hyperproliferation of PASMCs. The pathological relevance of VELRP upregulation in pulmonary artery was confirmed using rat pulmonary hypertension models in vivo, as well as in PASMCs from patients with idiopathic pulmonary arterial hypertension. Specific knockdown of VELRP in smooth muscle cells using adeno-associated virus type 9 SM22α (smooth muscle protein 22α) promoter-shRNA-mediated silencing of VELRP resulted in a significant decrease in right ventricular systolic pressure and vascular remodeling in rat pulmonary hypertension model.

Conclusions: VELRP, as an lncRNA upregulated by PDGF-BB, mediates PASMC proliferation via WDR5/CDK signaling. In vivo studies demonstrate that targeted intervention of VELRP in smooth muscle cells can prevent the development of pulmonary hypertension.

Radiation therapy (RT) is a cornerstone in cancer treatment (used in 50% of cases), yet challenges persist because damage to normal tissue through direct impact of radiation or bystander effects is inevitable. Injury of macrovessels by RT manifests as obstructive disease, which is akin to atherosclerotic disease. Historically observed in coronary arteries of patients treated for breast cancer and lymphoma, it also affects patients receiving contemporary therapy for lung and chest cancers. Moreover, radiation at various sites can lead to peripheral vascular disease. An aspect of radiation-induced injury that has received little attention is microvascular injury, which typically results from damage to the endothelium and is considered the primary driver of RT-induced toxicity in the skin, kidney, and brain. This review delves into the clinical manifestations of RT-induced vascular disease, signaling pathways, cellular targets affected by radiation injury, and preclinical models of RT-induced vascular injury. The goal is to inspire the development of innovative strategies to prevent RT-related cardiovascular disease.

Background: COVID-19 is associated with acute risk of major adverse cardiac events (MACE), including myocardial infarction, stroke, and mortality (all-cause). However, the duration and underlying determinants of heightened risk of cardiovascular disease and MACE post-COVID-19 are not known.

Methods: Data from the UK Biobank was used to identify COVID-19 cases (n=10 005) who were positive for polymerase chain reaction (PCR⁺)-based tests for SARS-CoV-2 infection (n=8062) or received hospital-based International Classification of Diseases version-10 (ICD-10) codes for COVID-19 (n=1943) between February 1, 2020 and December 31, 2020. Population controls (n=217 730) and propensity score-matched controls (n=38 860) were also drawn from the UK Biobank during the same period. Proportional hazard models were used to evaluate COVID-19 for association with long-term (>1000 days) risk of MACE and as a coronary artery disease risk equivalent. Additional analyses examined whether COVID-19 interacted with genetic determinants to affect the risk of MACE and its components.

Results: The risk of MACE was elevated in COVID-19 cases at all levels of severity (HR, 2.09 [95% CI, 1.94-2.25]; P<0.0005) and to a greater extent in cases hospitalized for COVID-19 (HR, 3.85 [95% CI, 3.51-4.24]; P<0.0005). Hospitalization for COVID-19 represented a coronary artery disease risk equivalent since incident MACE risk among cases without history of cardiovascular disease was even higher than that observed in patients with cardiovascular disease without COVID-19 (HR, 1.21 [95% CI, 1.08-1.37]; P<0.005). A significant genetic interaction was observed between the ABO locus and hospitalization for COVID-19 (P_interaction=0.01), with risk of thrombotic events being increased in subjects with non-O blood types (HR, 1.65 [95% CI, 1.29-2.09]; P=4.8×10^-5) to a greater extent than subjects with blood type O (HR, 0.96 [95% CI, 0.66-1.39]; P=0.82).

Conclusions: Hospitalization for COVID-19 represents a coronary artery disease risk equivalent, with post-acute myocardial infarction and stroke risk particularly heightened in non-O blood types. These results may have important clinical implications and represent, to our knowledge, one of the first examples of a gene-pathogen exposure interaction for thrombotic events.

Background: Platelets play an important role in cardiovascular and cerebrovascular diseases. Abdominal aortic aneurysm (AAA) is a highly lethal, atherosclerosis-related disease with characteristic features of progressive dilatation of the abdominal aorta and degradation of the vessel wall, accompanied by chronic inflammation. Platelet activation and procoagulant activity play a decisive role in the AAA pathology as they might trigger AAA development in both mice and humans.

Methods: The present study investigated the impact of the major platelet collagen receptor GP (platelet glycoprotein) VI in pathophysiological processes underlying AAA initiation and progression. For experimental AAA induction in mice, PPE (porcine pancreatic elastase) and the external PPE model were used.

Results: Genetic deletion of GP VI offered protection of mice against aortic diameter expansion in experimental AAA. Mechanistically, GP VI deficiency resulted in decreased inflammation with reduced infiltration of neutrophils and platelets into the aortic wall. Furthermore, remodeling of the aortic wall was improved in the absence of GP VI, as indicated by reduced MMP (matrix metalloproteinase)-2/9 and OPN (osteopontin) plasma levels and an enhanced α-SMA (α-smooth muscle actin) content within the aortic wall, accompanied by reduced cell apoptosis. Consequently, an elevation in intima/media thickness and elastin content was observed in GP VI-deficient PPE mice, resulting in a significantly reduced aortic diameter expansion and reduced aneurysm incidence. In patients with AAA, enhanced plasma levels of soluble GP VI and fibrin, as well as fibrin accumulation within the intraluminal thrombus might serve as new biomarkers to detect AAA early. Moreover, we hypothesize that GP VI might play a role in procoagulant activity and thrombus stabilization via binding to fibrin.

Conclusions: In conclusion, our results emphasize the potential need for a GP VI-targeted antiplatelet therapy to reduce AAA initiation and progression, as well as to protect patients with AAA from aortic rupture.

Background: Atherosclerosis is a progressive inflammatory disease in which macrophage foam cells play a central role in disease pathogenesis. SPA (surfactant protein A) is a lipid-associating protein involved with regulating macrophage function in various inflammatory diseases. However, the role of SPA in atherosclerosis and macrophage foam cell formation has not been investigated.

Methods: SPA expression was assessed in healthy and atherosclerotic human coronary arteries and the brachiocephalic arteries of wild-type or ApoE-deficient mice fed high-fat diets for 4 weeks. Hypercholesteremic wild-type and SPA-deficient mice fed a high-fat diet for 6 weeks were investigated for atherosclerotic lesions in vivo. In vitro experiments using RAW264.7 macrophages, primary resident peritoneal macrophages extracted from wild-type or SPA-deficient mice, and human monocyte-derived macrophages from the peripheral blood of healthy donors determined the functional effects of SPA in macrophage foam cell formation.

Results: SPA expression was increased in atherosclerotic lesions in humans and ApoE-deficient mice and in response to a proatherosclerotic stimulus in vitro. SPA deficiency reduced the lipid profiles induced by hypercholesterolemia, attenuated atherosclerosis, and reduced the number of lesion-associated macrophage foam cells. In vitro studies revealed that SPA deficiency reduced intracellular cholesterol accumulation and macrophage foam cell formation. Mechanistically, SPA deficiency dramatically downregulated the expression of scavenger receptor CD36 (cluster of differentiation antigen 36) cellular and lesional expression. Importantly, SPA also increased CD36 expression in human monocyte-derived macrophages.

Conclusions: Our results elucidate that SPA is a novel factor promoting atherosclerosis development. SPA enhances macrophage foam cell formation and atherosclerosis by increasing scavenger receptor CD36 expression, leading to increasing cellular OxLDL influx.

Background: Familial chylomicronemia syndrome (FCS) is a rare autosomal recessive disorder. This study aimed to study the genotype distribution of FCS-causing genes in the United Kingdom, genotype-phenotype correlation, and clinical differences between FCS and multifactorial chylomicronemia syndrome (MCS).

Methods: The study included 154 patients (FCS, 74; MCS, 80) from the UK FCS national registry and the UK arm of the FCS International Quality Improvement and Service Evaluation Project.

Results: FCS was relatively common in non-Europeans and those with parental consanguinity (P<0.001 for both). LPL variants were more common in European patients with FCS (European, 64%; non-European, 46%), while the genotype was more diverse in non-European patients with FCS. Patients with FCS had a higher incidence compared with patients with MCS of acute pancreatitis (84% versus 60%; P=0.001), recurrent pancreatitis (92% versus 63%; P<0.001), unexplained abdominal pain (84% versus 52%; P<0.001), earlier age of onset (median [interquartile range]) of symptoms (15.0 [5.5-26.5] versus 34.0 [25.2-41.7] years; P<0.001), and of acute pancreatitis (24.0 [10.7-31.0] versus 33.5 [26.0-42.5] years; P<0.001). Adverse cardiometabolic features and their co-occurrence was more common in individuals with MCS compared with those with FCS (P<0.001 for each). Atherosclerotic cardiovascular disease was more prevalent in individuals with MCS than those with FCS (P=0.04). However, this association became nonsignificant after adjusting for age, sex, and body mass index. The prevalence of pancreatic complications and cardiometabolic profile of variant-positive MCS was intermediate between FCS and variant-negative MCS.

Conclusions: The frequency of gene variant distribution varies based on the ethnic origin of patients with FCS. Patients with FCS are at a higher risk of pancreatic complications while the prevalence of atherosclerotic cardiovascular disease is lower in FCS compared with MCS. Carriers of heterozygous pathogenic variants have an intermediate phenotype between FCS and variant-negative MCS.

Background: Coronary atherosclerotic plaques susceptible to acute coronary syndrome have traditionally been characterized by their surrounding cellular architecture. However, with the advent of intravascular imaging, novel mechanisms of coronary thrombosis have emerged, challenging our contemporary understanding of acute coronary syndrome. These intriguing findings underscore the necessity for a precise molecular definition of plaque stability. Considering this, our study aimed to investigate the vascular microenvironment in patients with stable and unstable plaques using spatial transcriptomics.

Methods: Autopsy-derived coronary arteries were preserved and categorized by plaque stability (n=5 patients per group). We utilized the GeoMx spatial profiling platform and Whole Transcriptome Atlas to link crucial histological morphology markers in coronary lesions with differential gene expression in specific regions of interest, thereby mapping the vascular transcriptome. This innovative approach allowed us to conduct cell morphological and spatially resolved transcriptional profiling of atherosclerotic plaques while preserving crucial intercellular signaling.

Results: We observed intriguing spatial and cell-specific transcriptional patterns in stable and unstable atherosclerotic plaques, showcasing regional variations within the intima and media. These regions exhibited differential expression of proinflammatory molecules (eg, IFN-γ [interferon-γ], MHC [major histocompatibility complex] class II, proinflammatory cytokines) and prothrombotic signaling pathways. By using lineage tracing through spatial deconvolution of intimal CD68⁺ (cluster of differentiation 68) cells, we characterized unique, intraplaque subpopulations originating from endothelial, smooth muscle, and myeloid lineages with distinct regional locations associated with plaque instability. In addition, unique transcriptional signatures were observed in vascular smooth muscle and CD68⁺ cells among plaques exhibiting coronary calcification.

Conclusions: Our study illuminates distinct cell-specific and regional transcriptional alterations present in unstable plaques. Furthermore, we characterize spatially resolved, in situ evidence supporting cellular transdifferentiation and intraplaque plasticity as significant contributors to plaque instability in human coronary atherosclerosis. Our results provide a powerful resource for the identification of novel mediators of acute coronary syndrome, opening new avenues for preventative and therapeutic treatments.

Background: Store-operated calcium entry mediated by STIM (stromal interaction molecule)-1-Orai1 (calcium release-activated calcium modulator 1) is essential in endothelial cell (EC) functions, affecting signaling, NFAT (nuclear factor for activated T cells)-induced transcription, and metabolic programs. While the small GTPase Rap1 (Ras-proximate-1) isoforms, including the predominant Rap1B, are known for their role in cadherin-mediated adhesion, EC deletion of Rap1A after birth uniquely disrupts lung endothelial barrier function. Here, we elucidate the specific mechanisms by which Rap1A modulates lung vascular integrity and inflammation.

Methods: The role of EC Rap1A in lung inflammation and permeability was examined using in vitro and in vivo approaches.

Results: We explored Ca²⁺ signaling in human ECs following siRNA-mediated knockdown of Rap1A or Rap1B. Rap1A knockdown, unlike Rap1B, significantly increased store-operated calcium entry in response to a GPCR (G-protein-coupled receptor) agonist, ATP (500 µmol/L), or thapsigargin (250 nmol/L). This enhancement was attenuated by Orai1 channel blockers 10 μmol/L BTP2 (N-[4-[3,5-bis(trifluoromethyl)-1H-pyrazol-1-yl]phenyl]-4-methyl-1,2,3-thiadiazole-5-carboxamide), 10 μmol/L GSK-7975A, and 5 μmol/L Gd³⁺. Whole-cell patch clamp measurements revealed enhanced Ca²⁺ release-activated Ca²⁺ current density in siRap1A ECs. Rap1A depletion in ECs led to increased NFAT1 nuclear translocation and activity and elevated levels of proinflammatory cytokines (CXCL1 [C-X-C motif chemokine ligand 1], CXCL11 [C-X-C motif chemokine 11], CCL5 [chemokine (C-C motif) ligand 5], and IL-6 [interleukin-6]). Notably, reducing Orai1 expression in siRap1A ECs normalized store-operated calcium entry, NFAT activity, and endothelial hyperpermeability in vitro. EC-specific Rap1A knockout (Rap1A^iΔEC) mice displayed an inflammatory lung phenotype with increased lung permeability and inflammation markers, along with higher Orai1 expression. Delivery of siRNA against Orai1 to lung endothelium using lipid nanoparticles effectively normalized Orai1 levels in lung ECs, consequently reducing hyperpermeability and inflammation in Rap1A^iΔEC mice.

Conclusions: Our findings uncover a novel role of Rap1A in regulating Orai1-mediated Ca²⁺ entry and expression, crucial for NFAT-mediated transcription and endothelial inflammation. This study distinguishes the unique function of Rap1A from that of the predominant Rap1B isoform and highlights the importance of normalizing Orai1 expression in maintaining lung vascular integrity and modulating endothelial functions.