Arteriosclerosis, Thrombosis, and Vascular Biology最新文献

Background: Clinical expressivity of the thrombophilic factor V Leiden (FVL) mutation is highly variable. Recently, we demonstrated an increased APC (activated protein C) response in asymptomatic FVL carriers compared with FVL carriers with a history of venous thromboembolism (VTE) after in vivo coagulation activation. Here, we further explored this association using a recently developed ex vivo model based on patient-specific endothelial colony-forming cells (ECFCs).

Methods: ECFCs and citrated plasma were obtained from FVL carriers with previous VTE (VTE+, n=9), FVL carriers without previous VTE (VTE-, n=8), and 7 healthy controls. Coagulation was activated by TF (tissue factor) in defibrinated recalcified plasma added to confluent cell cultures. Thrombin and APC concentration were measured over time, and the respective areas under the curve were calculated. Additionally, inhibition kinetics of exogenously added APC, APC inhibitor levels, and APC sensitivity ratios were measured in plasma. Expression of TM (thrombomodulin) and EPCR (endothelial protein C receptor) on ECFCs was assessed using cell-based ELISAs.

Results: In autologous plasma on ECFCs, the APC response (area under the curve APC/area under the curve thrombin) was higher in FVL VTE- than in FVL VTE+ patients (0.138 versus 0.028; P=0.026). APC inhibitor levels, APC inactivation kinetics, and APC sensitivity ratios did not differ between cohorts. Crossover experiments, which combined pooled plasma from FVL VTE- patients with FVL VTE+ ECFCs in the ex vivo model, and vice versa, showed increased APC response rates when FVL VTE- ECFCs were used, regardless of the plasma component. In cell-based ELISAs, TM and EPCR expression showed no significant difference.

Conclusions: Although the FVL gene product induces an almost identical APC resistance phenotype in plasma, the endothelial cell-dependent APC response rates differ significantly, with a higher APC response in asymptomatic FVL carriers. Further studies are warranted to elucidate the disease-modulating role of the endothelium in FVL carriers at the molecular level.

Background: Hypoxia is associated with the onset of cardiovascular diseases including cardiac hypertrophy and pulmonary hypertension. HIF2 (hypoxia-inducible factor 2) signaling in the endothelium mediates pulmonary arterial remodeling and subsequent elevation of the right ventricular systolic pressure during chronic hypoxia. Thus, novel therapeutic opportunities for pulmonary hypertension based on specific HIF2 inhibitors have been proposed. Nevertheless, HIF2 relevance beyond the pulmonary endothelium or in the cardiac adaptation to hypoxia remains elusive. Wt1 (Wilms tumor 1) lineage contributes to the heart and lung vascular compartments, including pericytes, endothelial cells, and smooth muscle cells.

Methods: Here, we describe the response to chronic hypoxia of a novel HIF2 mutant mouse model in the Wt1 lineage (Hif2/Wt1 cKO), characterizing structural and functional aspects of the heart and lungs by means of classical histology, immunohistochemistry, flow cytometry, echocardiography, and lung ultrasound analysis.

Results: Hif2/Wt1 cKO is protected against pulmonary remodeling and increased right ventricular systolic pressure induced by hypoxia but displays alveolar congestion, inflammation, and hemorrhages associated with microvascular instability. Furthermore, lack of HIF2 in the Wt1 lineage leads to cardiomegaly, capillary remodeling, right and left ventricular hypertrophy, systolic dysfunction, and left ventricular dilation, suggesting pulmonary-independent cardiac direct roles of HIF2 in hypoxia. These structural defects are partially restored upon reoxygenation, while cardiac functional parameters remain altered.

Conclusions: Our results indicate that cardiopulmonary HIF2 signaling prevents excessive vascular proliferation during chronic hypoxia and define novel protective roles of HIF2 to warrant stable microvasculature and organ function.

Background: The ECM (extracellular matrix) provides the microenvironmental niche sensed by resident vascular smooth muscle cells (VSMCs). Aging and disease are associated with dramatic changes in ECM composition and properties; however, their impact on the VSMC phenotype remains poorly studied.

Methods: Here, we describe a novel in vitro model system that utilizes endogenous ECM to study how modifications associated with age and metabolic disease impact the VSMC phenotype. ECM was synthesized using primary human VSMCs and modified during culture or after decellularization. Integrity, stiffness, and composition of the ECM was measured using superresolution microscopy, atomic force microscopy, and proteomics, respectively. VSMCs reseeded onto the modified ECM were analyzed for viability and osteogenic differentiation.

Results: ECMs produced in response to mineral stress showed extracellular vesicle-mediated hydroxyapatite deposition and sequential changes in collagen composition and ECM properties. VSMCs seeded onto the calcified ECM exhibited increased extracellular vesicle release and Runx2 (Runt-related transcription factor 2)-mediated osteogenic gene expression due to the uptake of hydroxyapatite, which led to increased reactive oxygen species and the induction of DNA damage signaling. VSMCs seeded onto the nonmineralized, senescent ECM also exhibited increased Runx2-mediated osteogenic gene expression and accelerated calcification. In contrast, glycated ECM specifically induced increased ALP (alkaline phosphatase) activity, and this was dependent on RAGE (receptor for advanced glycation end products) signaling with both ALP and RAGE receptor inhibition attenuating calcification.

Conclusions: ECM modifications associated with aging and metabolic disease can directly induce osteogenic differentiation of VSMCs via distinct mechanisms and without the need for additional stimuli. This highlights the importance of the ECM microenvironment as a key driver of phenotypic modulation acting to accelerate age-associated vascular pathologies and provides a novel model system to study the mechanisms of calcification.

Modulating immune function is a critical strategy in cancer and atherosclerosis treatments. For cancer, boosting or maintaining the immune system is crucial to prevent tumor growth. However, in vascular disease, mitigating immune responses can decrease inflammation and slow atherosclerosis progression. Anti-inflammatory therapy, therefore, presents a unique dilemma for cancer survivors: while it may decrease cardiovascular risk, it might also promote cancer growth and metastasis by suppressing the immune response. Senescence presents a potentially targetable solution to this challenge; senescence increases the risk of both cancer therapy resistance and vascular disease. Exercise, notably, shows promise in delaying this premature senescence, potentially improving cancer outcomes and lowering vascular disease risk post-treatment. This review focuses on the long-term impact of cancer therapies on vascular health. We underscore the importance of modulating senescence to balance cancer treatment's effectiveness and its vascular impact, and we emphasize investigating the role of exercise-mediated suppression of senescence in improving cancer survivorship.

The field of cardio-oncology has traditionally focused on the impact of cancer and its therapies on cardiovascular health. Mounting clinical and preclinical evidence, however, indicates that the reverse may also be true: cardiovascular disease can itself influence tumor growth and metastasis. Numerous epidemiological studies have reported that individuals with prevalent cardiovascular disease have an increased incidence of cancer. In parallel, studies using preclinical mouse models of myocardial infarction, heart failure, and cardiac remodeling support the notion that cardiovascular disorders accelerate the growth of solid tumors and metastases. These findings have ushered in a new and burgeoning field termed reverse cardio-oncology that investigates the impact of cardiovascular disease cause and pathophysiology on cancer emergence and progression. Recent studies have begun to illuminate the mechanisms driving this relationship, including shared risk factors, reprogramming of immune responses, changes in gene expression, and the release of cardiac factors that result in selective advantages for tumor cells or their local milieu, thus exacerbating cancer pathology. Here, we review the evidence supporting the relationship between cardiovascular disease and cancer, the mechanistic pathways enabling this connection, and the implications of these findings for patient care.

Background: Smooth muscle cells (SMCs) of the proximal thoracic aorta are derived from second heart field (SHF) and cardiac neural crest lineages. Recent studies, both in vitro and in vivo, have implied relevance of lineage-specific SMC functions in the pathophysiology of thoracic aortic diseases; however, whether 2 lineage-derived SMCs have any predisposed transcriptional differences in the control aorta remains unexplored.

Methods: Single-cell RNA sequencing and single-nucleus assay for transposase-accessible chromatin sequencing were performed on isolated cells from the aortic root and ascending aortas of 14-week-old SHF-traced (Mef2c-Cre^+/0-Yfp^+/0) and cardiac neural crest-traced (Wnt1-Cre^+/0-Yfp^+/0) male mice. RNA in situ hybridization was performed for spatial expression of selected differentially expressed genes (DEGs) of both lineages.

Results: Lineage stratification of SMCs in the proximal thoracic aorta was identified using antibody-based immunofluorescence staining. Single-cell RNA sequencing recognized 12 consistently upregulated DEGs (Des, Tnnt2, Hand2os1, Psd, Gpc3, Meis2, Dcn, Gm34030, Palld, Nrtn, Lum, and Cfh) in SHF-derived SMCs and 9 consistently upregulated DEGs (Ccn5, Ccdc42, Tes, Eln, Aebp1, Galnt6, Ccn2, Aopep, and Wtip) in cardiac neural crest-derived SMCs. RNA in situ hybridization validated upregulated expressions of selective SHF-specific DEGs at the aortic root. We found SHF-derived SMCs contain a distinct, large subpopulation of SMCs that is enriched with Des and Tnnt2 expressions. Single-nucleus assay for transposase-accessible chromatin analysis further confirmed higher chromosomal accessibility for upregulated DEGs of SHF-derived SMCs.

Conclusions: The present study recognizes the presence of limited but distinct transcriptomic differences between cardiac neural crest-derived and SHF-derived SMCs in the control proximal thoracic aorta.

Preeclampsia is a multisystem hypertensive disorder that manifests itself after 20 weeks of pregnancy, along with proteinuria. The pathophysiology of preeclampsia is incompletely understood. Artificial intelligence, especially machine learning with its capability to identify patterns in complex data, has the potential to revolutionize preeclampsia research. These data-driven techniques can improve early diagnosis, personalize risk assessment, uncover the disease's molecular basis, optimize treatments, and enable remote monitoring. This brief review discusses the recent applications of artificial intelligence and machine learning in preeclampsia management and research, including the improvements these approaches have brought, along with their challenges and limitations.

Atherosclerosis affects patients with systemic immune-mediated inflammatory diseases at an increased rate compared with the general population. In recent years, our understanding of the pathophysiology of atherosclerosis has advanced considerably. Nevertheless, cardiovascular imaging modalities that can adequately assess the biological background of atherosclerosis have not reached widespread clinical adoption. Novel developments in cardiac imaging have the potential to enhance the diagnostic yield of these modalities further while providing essential insights into the anatomy, composition, and biology of atherosclerotic lesions. In this review, we highlight some of the latest developments in the field for the evaluation of atherosclerosis using advances in echocardiography, computed tomography, positron emission tomography, and cardiovascular magnetic resonance. Additionally, we discuss evidence specifically in patients with immune-mediated inflammatory diseases and outline unmet research needs for future development.

Background: apoER2 (apolipoprotein E receptor-2) is a transmembrane receptor in the low-density lipoprotein receptor (LDLR) family with unique tissue expression. A single-nucleotide polymorphism that encodes the R952Q sequence variant has been associated with elevated plasma cholesterol levels and increased myocardial infarction risk in humans. The objective of this study was to delineate the mechanism underlying the association between the apoER2 variant with arginine-to-glutamine substitution at residue 952 (R952Q) and increased atherosclerosis risk.

Methods: An apoER2 R952Q mouse model was generated and intercrossed with LDLR knockout mice, followed by feeding a Western-type high-fat high-cholesterol diet for 16 weeks. Atherosclerosis was investigated by immunohistology. Plasma lipids and lipid distributions among the various lipoprotein classes were analyzed by colorimetric assay. Tissue-specific effects of the R952Q sequence variant on atherosclerosis were analyzed by bone marrow transplant studies. sLRP1 (soluble low-density lipoprotein receptor-related protein 1) was measured in plasma and conditioned media from bone marrow-derived macrophages by ELISA and GST-RAP (glutathione S-transferase-receptor-associated protein) pull-down, respectively. P38 MAPK (mitogen-activated protein kinase) phosphorylation in VLDL (very-low-density lipoprotein)-treated macrophages was determined by Western blot analysis.

Results: Consistent with observations in humans with this sequence variant, the apoER2 R952Q mutation exacerbated diet-induced hypercholesterolemia, via impediment of plasma triglyceride-rich lipoprotein clearance, to accelerate atherosclerosis in Western diet-fed LDLR knockout mice. Reciprocal bone marrow transplant experiments revealed that the apoER2 R952Q mutation in bone marrow-derived cells instead of non-bone marrow-derived cells was responsible for the increase in hypercholesterolemia and atherosclerosis. Additional data showed that the apoER2 R952Q mutation in macrophages promotes VLDL-induced LRP1 (low-density lipoprotein receptor-related protein 1) shedding in a p38 MAPK-dependent manner.

Conclusions: The apoER2 R952Q mouse model recapitulates characteristics observed in human disease. The underlying mechanism is that the apoER2 R952Q mutation in macrophages exacerbates VLDL-stimulated sLRP1 production in a p38 MAPK-dependent manner, resulting in its competition with cell surface LRP1 to impede triglyceride-rich lipoprotein clearance, thereby resulting in increased hypercholesterolemia and accelerated atherosclerosis.