Role Of Endothelial Cells Research Articles

The Role of Iron in Atherosclerosis and its Association with Related Diseases.

This review aims to elucidate the multifaceted role of iron in the pathogenesis of atherosclerosis. The primary objective is to summarize recent advances in understanding how iron contributes to atherosclerosis through various cellular mechanisms. Additionally, the review explores the therapeutic implications of targeting iron metabolism in the prevention and treatment of cardiovascular diseases. A growing body of literature suggests that excess iron accelerates the progression of atherosclerosis, with the deleterious form of iron, non-transferrin-bound iron (NTBI), particularly exacerbating this process. Furthermore, iron overload has been demonstrated to play a pivotal role in endothelial cells, vascular smooth muscle cells, and macrophages, contributing to plaque instability and disease progression by promoting lipid peroxidation, oxidative stress, inflammatory responses, and ferroptosis. Iron plays a complex role in atherosclerosis, influencing multiple cellular processes and promoting disease progression. By promoting oxidative stress, inflammation, and ferroptosis, iron exacerbates endothelial dysfunction, smooth muscle cell calcification, and the formation of macrophage-derived foam cells. Targeted therapies focusing on iron metabolism have proven effective in treating atherosclerosis and other cardiovascular diseases.

Endothelial metabolic control of insulin sensitivity through resident macrophages

Endothelial cells (ECs) not only form passive blood conduits but actively contribute to nutrient transport and organ homeostasis. The role of ECs in glucose homeostasis is, however, poorly understood. Here, we show that, in skeletal muscle, endothelial glucose transporter 1 (Glut1/Slc2a1) controls glucose uptake via vascular metabolic control of muscle-resident macrophages without affecting transendothelial glucose transport. Lowering endothelial Glut1 via genetic depletion (Glut1ΔEC) or upon a short-term high-fat diet increased angiocrine osteopontin (OPN/Spp1) secretion. This promoted resident muscle macrophage activation and proliferation, which impaired muscle insulin sensitivity. Consequently, co-deleting Spp1 from ECs prevented macrophage accumulation and improved insulin sensitivity in Glut1ΔEC mice. Mechanistically, Glut1-dependent endothelial glucose metabolic rewiring increased OPN in a serine metabolism-dependent fashion. Our data illustrate how the glycolytic endothelium creates a microenvironment that controls resident muscle macrophage phenotype and function and directly links resident muscle macrophages to the maintenance of muscle glucose homeostasis.

Dynamics of Endothelial Cell Diversity and Plasticity in Health and Disease.

Endothelial cells (ECs) are vital structural units of the cardiovascular system possessing two principal distinctive properties: heterogeneity and plasticity. Endothelial heterogeneity is defined by differences in tissue-specific endothelial phenotypes and their high predisposition to modification along the length of the vascular bed. This aspect of heterogeneity is closely associated with plasticity, the ability of ECs to adapt to environmental cues through the mobilization of genetic, molecular, and structural alterations. The specific endothelial cytoarchitectonics facilitate a quick structural cell reorganization and, furthermore, easy adaptation to the extrinsic and intrinsic environmental stimuli, known as the epigenetic landscape. ECs, as universally distributed and ubiquitous cells of the human body, play a role that extends far beyond their structural function in the cardiovascular system. They play a crucial role in terms of barrier function, cell-to-cell communication, and a myriad of physiological and pathologic processes. These include development, ontogenesis, disease initiation, and progression, as well as growth, regeneration, and repair. Despite substantial progress in the understanding of endothelial cell biology, the role of ECs in healthy conditions and pathologies remains a fascinating area of exploration. This review aims to summarize knowledge and concepts in endothelial biology. It focuses on the development and functional characteristics of endothelial cells in health and pathological conditions, with a particular emphasis on endothelial phenotypic and functional heterogeneity.

TMEM16F scramblase regulates angiogenesis via endothelial intracellular signaling.

TMEM16F (also known as ANO6), a Ca2+-activated lipid scramblase (CaPLSase) that dynamically disrupts lipid asymmetry, plays a crucial role in various physiological and pathological processes, such as blood coagulation, neurodegeneration, cell-cell fusion and viral infection. However, the mechanisms through which it regulates these processes remain largely elusive. Using endothelial cell-mediated angiogenesis as a model, here we report a previously unknown intracellular signaling function of TMEM16F. We demonstrate that TMEM16F deficiency impairs developmental retinal angiogenesis in mice and disrupts angiogenic processes in vitro. Biochemical analyses indicate that the absence of TMEM16F enhances the plasma membrane association of activated Src kinase. This in turn increases VE-cadherin phosphorylation and downregulation, accompanied by suppressed angiogenesis. Our findings not only highlight the role of intracellular signaling by TMEM16F in endothelial cells but also open new avenues for exploring the regulatory mechanisms for membrane lipid asymmetry and their implications in disease pathogenesis.

The Role of Endothelial Cells in Sickle Cell Hemoglobin Clearance: What Do We Know So Far?

The Role of Endothelial Cells in Sickle Cell Hemoglobin Clearance: What Do We Know So Far?

#1293 Endothelial calcification induced by high-phosphate is characterized by mesenchymal and osteoblastic transdifferentiation

Abstract Background and Aims Chronic kidney disease (CKD) is a prevalent condition that affects millions of people. Patients with CKD have an increased cardiovascular risk, mostly due to vascular calcification (VC). By now, it's quite clear how, in vitro and in vivo, vascular smooth muscle cells (VSMCs) actively participate to VC. In contrast to the wide studies on VSMCs, the role of endothelial cells (ECs) has been poorly investigated. It's known that ECs have a dynamic nature and following particular stimuli they can trans-differentiate and acquire several different phenotypes through the endothelial-to-mesenchymal transition (EndMT). Methods Human aortic ECs (HAECs) were challenged, in an in vitro calcification model, with 2, 2.5, 3, 3.5 mM Pi for up to 7 days. Early morphological changes, gene expression and cell migration were evaluated. Afterwards calcium deposition, genes and protein expression and ultrastructural changes were analyzed. Results High-Pi, at a concentration of 3 mM, is able to induce EC calcium deposition. Calcification is dependent on calcium influx without influencing Pit-1 expression. During the first days of high-Pi treatment ECs change their morphology from cobblestone to spindle shape acquiring motility, as demonstrated by the 24% increased closure in the scratch wound test. EndMT master genes such as SNAIL and TWIST resulted up-regulated at day 3 together with an increased protein expression of mesenchymal markers such as N-Cadherin, α-SMA, SM22α, FSP-1 and Fibronectin. Starting from day 5 high-Pi induces osteoblastic differentiation with RUNX2 and BMP2 mRNA up-regulation up to day 7, osteopontin increased protein expression and positive Alcian Blu staining. In calcified ECs mesenchymal and endothelial markers, such as α-SMA, SM22α, FSP-1 and Fibronectin or vWF progressively decrease. Finally, uremic serum is able to exacerbate in vitro calcification, compared to healthy serum characterized by an increase in both mesenchymal and osteoblastic mastergene such as TWIST and RUNX2. Conclusions Our data demonstrate that in vitro high-Pi induces the EndMT process and similar osteoblastic trans-differentiation suggesting a potential role of endothelium in VC. The relevancy of endothelial calcification is suggested by the calcification exacerbation induced by uremic compared to healthy sera.

Brain endothelial cells promote breast cancer cell extravasation to the brain via EGFR-DOCK4-RAC1 signalling.

The role of endothelial cells in promoting cancer cell extravasation to the brain during the interaction of cancer cells with the vasculature is not well characterised. We show that brain endothelial cells activate EGFR signalling in triple-negative breast cancer cells with propensity to metastasise to the brain. This activation is dependent on soluble factors secreted by brain endothelial cells, and occurs via the RAC1 GEF DOCK4, which is required for breast cancer cell extravasation to the brain in vivo. Knockdown of DOCK4 inhibits breast cancer cell entrance to the brain without affecting cancer cell survival or growth. Defective extravasation is associated with loss of elongated morphology preceding intercalation into brain endothelium. We also showthat brain endothelial cells promote paracrine stimulation of mesenchymal-like morphology of breast cancer cells via DOCK4, DOCK9, RAC1 and CDC42. This stimulation is accompanied by EGFR activation necessary for brain metastatic breast cancer cell elongation which can be reversed by the EGFR inhibitor Afatinib. Our findings suggest that brain endothelial cells promote metastasis through activation of cell signalling that renders breast cancer cells competent for extravasation. This represents a paradigm of brain endothelial cells influencing the signalling and metastatic competency of breast cancer cells.

The Role of Endothelial Cell Specific Nrf2 on Skeletal Muscle Mitochondrial Function

Introduction: Cardiovascular disease (CVD) is a leading cause of death worldwide. Excessive reactive oxygen species (ROS) in the vasculature has been suggested as one of the major players in CVD. In addition, CVDs such as peripheral arterial disease (PAD) have elevated oxidative stress (OS) damage, stemming from an imbalance between antioxidants and ROS in both the vasculature and skeletal muscles. Although a vascular disease, the most common symptom of PAD is leg pain due to skeletal muscle ischemia and OS damage. The Nuclear factor erythroid 2-related factor 2 (Nrf2)-Kelch-like ECH-associated protein 1 (Keap1) pathway is a redox transcription factor and is likely the master regulator of endogenous antioxidants. Modulation of Nrf2 expression may be a potential therapeutic target in CVDs. However, the role of endothelial cell (EC) Nrf2 on skeletal muscle mitochondrial function is currently unknown. Therefore, the purpose of this study was to examine the role of endothelial specific Nrf2 in skeletal muscle mitochondrial function.Hypothesis: We hypothesized that 1) EC-specific Nrf2-knockout (Tie2-Cre-Nrf2 Floxed) would result in blunted skeletal muscle mitochondrial function and 2) EC specific Keap1 knockout (Tie2-Cre-Keap1 Floxed) would improve skeletal muscle mitochondrial function. Methods: Gastrocnemius muscles were harvested from 6-month-old C57BL/6 mice (WT, n = 11), EC specific Nrf2-KO mice (n = 15) and EC specific Keap1-KO mice (n = 7). Muscle fibers were permeabilized and placed in a high-resolution respirometer to assess mitochondrial respiratory complex function (Oroboros Instruments). Results: Complex I state 3 respiration was blunted in Nrf2-KO compared to both Keap1-KO and WT (6.5±1.7 vs 13.6±3.5 vs 18.5±3.3 pmols−1･mg−1, respectively; p<0.05). Complex I+II state 3 respiration was attenuated in Nrf2-KO compared to Keap1-KO (13.63±1.5 vs 27.8±4.2 pmols−1･mg−1; p<0.05). Complex II state 3 respiration was increased in the Keap1-KO compared to both Nrf2-KO and WT (23.9±2.8 vs 7.1±1.1 vs 5.6±0.7 pmols−1･mg−1, respectively; p<0.05) and Nrf2-KO exhibited reduced Complex IV respiration compared to both Keap1-KO and WT (19.5±6.1 vs 57.7±13.2 vs 76.6±12.4 pmols−1･mg−1, respectively; p<0.05).Conclusions: This study provides novel findings showing skeletal muscle mitochondrial dysfunction is present in EC specific Nrf2-KO mice. Yet, EC specific Keap1-KO mice had increased mitochondrial respiration. To our knowledge, this is the first study to demonstrate a substantial impact that EC specific Nrf2 contributes to skeletal muscle mitochondrial function. Our findings provide evidence that the vascular EC Nrf2 pathway can be a potential therapeutic target for skeletal muscle dysfunction in CVDs such as PAD. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Abstract 3100: BRCA1-RpL17 Interaction Regulates Angiogenesis

Background: Angiogenesis, forming new blood vessels from existing ones, is crucial in development, diabetes, and cancer. We found that Large Ribosomal subunit protein 17 (RpL17) played a key role in endothelial cell (EC) proliferation and angiogenesis. Reduced RpL17 (KD) promoted angiogenesis in human ECs and RpL17-deficient mouse retinas. RNA-sequencing and bioinformatics suggested a role for Early growth response 1(EGR1) transcription factor. Bioinformatics revealed Breast Cancer gene 1 (BRCA1) as a potential upstream regulator of RpL17, suggesting a novel pathway for angiogenesis. Hypothesis: BRCA1 interacts with RpL17 and upregulates EGR1 to stimulate vessel elongation in angiogenesis. Goal: Determine the role of BRCA1-RpL17 interaction in angiogenesis and their potential feedback loop via EGR1. Methods/Approach: RNA-sequencing of mouse ECs, whole retina mount staining (comparing wild-type and RpL17+/- mice). Tube formation assays with HUVECs to investigate angiogenesis after RpL17, BRCA1, and EGR1 knockdowns. Bioinformatics analysis with Python for RNA-seq data. Immunoblotting and RT-qPCR to measure protein and DNA expression. Immunofluorescence (IF) staining of HUVECs to observe BRCA1, RpL17, and EGR1 expression and localization. Preliminary Results: Whole retina mounts showed increased angiogenesis in RpL17-deficient mouse retinas compared to wildtype (p<0.009). HUVECs with RpL17 KD had increased junctions and longer branches than control HUVECs (p<0.0002). RNA-seq identified increased EGR1 expression (q<2.5x10 -8 ) in RpL17 KD ECs, confirmed with RT-qPCR (p<0.002). Bioinformatics predicted BRCA1 as a regulator of RpL17. HUVEC IF staining showed decreased RpL17 expression after BRCA1 KD. Angiogenesis assays of BRCA1 KD ECs exhibited an angiogenic phenotype like RpL17 KD, rescued following double BRCA1/RpL17 KD. Conclusion: BRCA1-RpL17 interaction stimulates angiogenesis and may be regulated by an EGR1 feedback loop, likely by EC proliferation. Detailed understanding of this pathway will provide new therapies to regulate angiogenesis.

Sided Stimulation of Endothelial Cells Modulates Neutrophil Trafficking in an In Vitro Sepsis Model.

While the role of dysregulated polymorphonuclear leukocyte (PMN) transmigration in septic mediated tissue damage is well documented, strategies to mitigate aberrant transmigration across endothelium have yet to yield viable therapeutics. Recently, microphysiological systems (MPS) have emerged as novel in vitro mimetics that facilitate the development of human models of disease. With this advancement, aspects of endothelial physiology that are difficult to assess with other models can be directly probed. In this study, the role of endothelial cell (EC) apicobasal polarity on leukocyte trafficking response is evaluated with the µSiM-MVM (microphysiological system enabled by a silicon membrane - microvascular mimetic). Here, ECs are stimulated either apically or basally with a cytokine cocktail to model a septic-like challenge before introducing healthy donor PMNs into the device. Basally oriented stimulation generated a stronger PMN transmigratory response versus apical stimulation. Importantly, healthy PMNs are unable to migrate towards a bacterial peptide chemoattractant when ECs are apically stimulated, which mimics the attenuated PMN chemotaxis seen in sepsis. Escalating the apical inflammatory stimulus by a factor of five is necessary to elicit high PMN transmigration levels across endothelium. These results demonstrate that EC apicobasal polarity modulates PMN transmigratory behavior and provides insight into the mechanisms underlying sepsis.

Protein Disulfide Isomerase 4 Is an Essential Regulator of Endothelial Function and Survival.

Endothelial autophagy plays an important role in the regulation of endothelial function. The inhibition of endothelial autophagy is associated with the reduced expression of protein disulfide isomerase 4 (PDIA-4); however, its role in endothelial cells is not known. Here, we report that endothelial cell-specific loss of PDIA-4 leads to impaired autophagic flux accompanied by loss of endothelial function and apoptosis. Endothelial cell-specific loss of PDIA-4 also induced marked changes in endothelial cell architecture, accompanied by the loss of endothelial markers and the gain of mesenchymal markers consistent with endothelial-to-mesenchymal transition (EndMT). The loss of PDIA-4 activated TGFβ-signaling, and inhibition of TGFβ-signaling suppressed EndMT in PDIA-4-silenced endothelial cells in vitro. Our findings help elucidate the role of PDIA-4 in endothelial autophagy and endothelial function and provide a potential target to modulate endothelial function and/or limit autophagy and EndMT in (patho-)physiological conditions.

Pericyte signaling via soluble guanylate cyclase shapes the vascular niche and microenvironment of tumors

Pericytes and endothelial cells (ECs) constitute the fundamental components of blood vessels. While the role of ECs in tumor angiogenesis and the tumor microenvironment is well appreciated, pericyte function in tumors remains underexplored. In this study, we used pericyte-specific deletion of the nitric oxide (NO) receptor, soluble guanylate cyclase (sGC), to investigate via single-cell RNA sequencing how pericytes influence the vascular niche and the tumor microenvironment. Our findings demonstrate that pericyte sGC deletion disrupts EC–pericyte interactions, impairing Notch-mediated intercellular communication and triggering extensive transcriptomic reprogramming in both pericytes and ECs. These changes further extended their influence to neighboring cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs) through paracrine signaling, collectively suppressing tumor growth. Inhibition of pericyte sGC has minimal impact on quiescent vessels but significantly increases the vulnerability of angiogenic tumor vessels to conventional anti-angiogenic therapy. In conclusion, our findings elucidate the role of pericytes in shaping the tumor vascular niche and tumor microenvironment and support pericyte sGC targeting as a promising strategy for improving anti-angiogenic therapy for cancer treatment.

Biomimetic engineered nanoparticles target drug-resistant tumor cells and heterogeneous blood vessels for combination therapy of osteosarcoma

Given that the treatment of drug-resistant osteosarcoma is a significant clinical challenge, in drug-resistant tumors, the role of endothelial cells has been recently emphasized. We noted that heterogeneous vascular endothelial cells (ONHVECs) in drug-resistant osteosarcoma tissues may inhibit macrophage-mediated killing of tumor cells, thus promoting the occurrence of drug resistance. Accordingly, we designed a type of hybrid membrane-coated multifunctional nanoparticle (NP), SiO2@PDA/Fe3+@Cis@HM. The NPs had good biocompatibility and enhanced the occurrence of low-temperature photothermal Fenton-like reactions. The hybrid membrane endowed the NPs with a tumor homing ability and homologous cell targeting ability, thus simultaneously targeting drug-resistant tumor cells and ONHVECs, in addition to killing tumor cells via efficient delivery of cisplatin and ROS produced by accelerated Fenton-like reactions. Through in vivo and in vitro experiments, we confirmed that SiO2@PDA/Fe3+@Cis@HM NPs efficiently killed tumor cells as well as ONHVECs. The endogenous exosomes produced by damaged ONHVECs induced anti-tumor M1 macrophage polarization to indirectly kill tumor cells and achieve synergistic therapy. This immune regulation was completely inherent and exhibited consistent efficacy, without ethical connotations. In conclusion, this multifunctional treatment strategy is the first to adopt a tumor cell/vascular endothelial cell double-targeted concept, which realized the direct killing of drug-resistant tumor cells and a natural immune enhancement response and could become a new paradigm for the treatment of drug-resistant osteosarcoma.

Endothelial TDP-43 controls sprouting angiogenesis and vascular barrier integrity, and its deletion triggers neuroinflammation.

TAR DNA-binding protein 43 (TDP-43) is a DNA/RNA-binding protein that regulates gene expression, and its malfunction in neurons has been causally associated with multiple neurodegenerative disorders. Although progress has been made in understanding the functions of TDP-43 in neurons, little is known about its roles in endothelial cells (ECs), angiogenesis, and vascular function. Using inducible EC-specific TDP-43-KO mice, we showed that TDP-43 is required for sprouting angiogenesis, vascular barrier integrity, and blood vessel stability. Postnatal EC-specific deletion of TDP-43 led to retinal hypovascularization due to defects in vessel sprouting associated with reduced EC proliferation and migration. In mature blood vessels, loss of TDP-43 disrupted the blood-brain barrier and triggered vascular degeneration. These vascular defects were associated with an inflammatory response in the CNS with activation of microglia and astrocytes. Mechanistically, deletion of TDP-43 disrupted the fibronectin matrix around sprouting vessels and reduced β-catenin signaling in ECs. Together, our results indicate that TDP-43 is essential for the formation of a stable and mature vasculature.

Non-Thyroidal Illness in Chronic Renal Failure: Triiodothyronine Levels and Modulation of Extra-Cellular Superoxide Dismutase (ec-SOD).

Oxidative stress (OS) is implicated in several chronic diseases. Extra-cellular superoxide dismutase (ec-SOD) catalyses the dismutation of superoxide anions with a protective role in endothelial cells. In chronic kidney disease (CKD), OS and thyroid dysfunction (low fT3 syndrome) are frequently present, but their relationship has not yet been investigated. This cohort study evaluated ec-SOD activity in CKD patients during haemodialysis, divided into "acute haemodialytic patients" (AH, 1-3 months of treatment) and "chronic haemodialytic patients" (CH, treated for a longer period). We also evaluated plasmatic total antioxidant capacity (TAC) and its relationships with thyroid hormones. Two basal samples ("basal 1", obtained 3 days after the last dialysis; and "basal 2", obtained 2 days after the last dialysis) were collected. On the same day of basal 2, a sample was collected 5 and 10 min after the standard heparin dose and at the end of the procedure. The ec-SOD values were significantly higher in CH vs. AH in all determinations. Moreover, the same patients had lower TAC values. When the CH patients were divided into two subgroups according to fT3 levels (normal or low), we found significantly lower ec-SOD values in the group with low fT3 in the basal, 5, and 10 min samples. A significant correlation was also observed between fT3 and ec-SOD in the basal 1 samples. These data, confirming OS and low fT3 syndrome in patients with CKD, suggest that low fT3 concentrations can influence ec-SOD activity and could therefore potentially contribute to endothelial oxidative damage in these patients.

Oral cancer cell to endothelial cell communication via exosomal miR-21/RMND5A pathway

Required for meiotic nuclear division 5 homolog A (RMND5A), a novel ubiquitin E3 Ligase, has been reported to correlate with poor prognosis of several cancers. However, its role in endothelial cells has not been reported. In this study, overexpression of RMND5A in human umbilical vein endothelial cells (HUVECs) was performed via lentiviral infection, followed by MTT, would healing and tube formation assay as well as signaling analysis. Moreover, crosstalk between HUVECs and oral squamous cell carcinoma (OSCC) cells was investigated by indirect co-culture with condition medium or tumor cell derived exosomes. Our results showed that overexpression of RMND5A reduced the proliferation, migration and tube formation ability of HUVECs by inhibiting the activation of ERK and NF-κB pathway. Interestingly, OSCC cells can inhibit RMND5A expression of endothelial cells via exosomal miR-21. In summary, our present study unveils that OSCC cells can activate endothelial cells via exosomal miR-21/RMND5A pathway to promote angiogenesis, which may provide novel therapeutic targets for the treatment of OSCC.

Endothelial periostin regulates vascular remodeling by promoting endothelial dysfunction in pulmonary arterial hypertension

ABSTRACT Pulmonary arterial hypertension (PAH) is characterized by vascular remodeling associated with extracellular matrix (ECM) deposition, vascular cell hyperproliferation, and neointima formation in the small pulmonary artery. Endothelial dysfunction is considered a key feature in the initiation of vascular remodeling. Although vasodilators have been used for the treatment of PAH, it remains a life-threatening disease. Therefore, it is necessary to identify novel therapeutic targets for PAH treatment. Periostin (POSTN) is a secretory ECM protein involved in physiological and pathological processes, such as tissue remodeling, cell adhesion, migration, and proliferation. Although POSTN has been proposed as a potential target for PAH treatment, its role in endothelial cells has not been fully elucidated. Here, we demonstrated that POSTN upregulation correlates with PAH by analyzing a public microarray conducted on the lung tissues of patients with PAH and biological experimental results from in vivo and in vitro models. Moreover, POSTN overexpression leads to ECM deposition and endothelial abnormalities such as migration. We found that PAH-associated endothelial dysfunction is mediated at least in part by the interaction between POSTN and integrin-linked protein kinase (ILK), followed by activation of nuclear factor-κB signaling. Silencing POSTN or ILK decreases PAH-related stimuli-induced ECM accumulation and attenuates endothelial abnormalities. In conclusion, our study suggests that POSTN serves as a critical regulator of PAH by regulating vascular remodeling, and targeting its role as a potential therapeutic strategy for PAH.

Identification Of Endothelial Cell Immune-related Gene Signature for Lung Adenocarcinoma by Integrated Analysis of Single-cell and Bulk RNA Sequencing Data.

Background: The role of endothelial cells in tumor progression is considerable, yet the effect of endothelial cell immune-related genes (EIRGs) is still unclear. This research aimed to scrutinize the prognostic value of EIRGs in lung adenocarcinoma (LUAD) and provide further insights into the abovementioned uncertainties. Methods: After single-cell RNA sequencing (scRNA-seq) samples were obtained from the Gene Expression Omnibus (GEO) database, they were integrated with bulk RNA sequencing data from The Cancer Genome Atlas (TCGA). Prognostic markers were determined and a prognostic model was developed. From this model, a nomogram was constructed. We analyzed the biological mechanism of the EIRGs in LUAD, including functional enrichment, tumor mutational burden (TMB), tumor microenvironment (TME) analyses and drug sensitivity. We validated the signature by validating the external cohort GSE31210 and RT-qPCR. Results: After analyzing the model constructed from eight EIRGs, we observed that high-risk group (HG) LUAD patients (a risk score exceeding 4.65) exhibited unfavorable outcomes according to Kaplan‒Meier survival curves. This outcome was confirmed by GSE31210. The nomogram based on the model demonstrated significant predictive value. HG was influenced primarily by steroid hormone biosynthesis and ECM receptor interactions. The TMB in HGs was greater than that in the LG. Analysis of drug sensitivity revealed the direction for individualized treatment for both risk cohorts. Variations in the expression of EIRGs have been confirmed via RT-qPCR in several LUAD cell lines. Conclusions: The prognostic model and nomogram above are valuable for determining the survival rate and treatment options for LUAD patients.

The Essential Role of Angiogenesis in Adenosine 2A Receptor Deficiency-mediated Impairment of Wound Healing Involving c-Ski via the ERK/CREB Pathways.

Adenosine receptor-mediated signaling, especially adenosine A2A receptor (A2AR) signaling, has been implicated in wound healing. However, the role of endothelial cells (ECs) in A2AR-mediated wound healing and the mechanism underlying this effect are still unclear. Here, we showed that the expression of A2AR substantially increased after wounding and was especially prominent in granulation tissue. The delaying effects of A2AR knockout (KO) on wound healing are due mainly to the effect of A2AR on endothelial cells, as shown with A2AR-KO and EC-A2AR-KO mice. Moreover, the expression of c-Ski, which is especially prominent in CD31-positive cells in granulation tissue, increased after wounding and was decreased by both EC-A2AR KO and A2AR KO. In human microvascular ECs (HMECs), A2AR activation induced EC proliferation, migration, tubule formation and c-Ski expression, whereas c-Ski depletion by RNAi abolished these effects. Mechanistically, A2AR activation promotes the expression of c-Ski through an ERK/CREB-dependent pathway. Thus, A2AR-mediated angiogenesis plays a critical role in wound healing, and c-Ski is involved mainly in the regulation of angiogenesis by A2AR via the ERK/CREB pathway. These findings identify A2AR as a therapeutic target in wound repair and other angiogenesis-dependent tissue repair processes.

Targeting Oncostatin M Receptor to Attenuate Carotid Artery Plaque Vulnerability in Hypercholesterolemic Microswine.

Atherosclerosis is a chronic inflammatory disease that leads to acute embolism via the formation of atherosclerotic plaques. Plaque formation is first induced by fatty deposition along the arterial intima. Inflammation, bacterial infection, and the released endotoxins can lead to dysfunction and phenotypic changes of vascular smooth muscle cells (VSMCs), advancing the plaque from stable to unstable form and prone to rupture. Stable plaques are characterized by increased VSMCs and less inflammation while vulnerable plaques develop due to chronic inflammation and less VSMCs. Oncostatin M (OSM), an inflammatory cytokine, plays a role in endothelial cells and VSMC proliferation. This effect of OSM could be modulated by p27KIP1, a cyclin-dependent kinase (CDK) inhibitor. However, the role of OSM in plaque vulnerability has not been investigated. To better understand the role of OSM and its downstream signaling including p27KIP1 in plaque vulnerability, we characterized the previously collected carotid arteries from hyperlipidemic Yucatan microswine using hematoxylin and eosin stain, Movat Pentachrome stain, and gene and protein expression of OSM and p27KIP1 using immunostaining and real-time polymerase chain reaction. OSM and p27KIP1 expression in carotid arteries with angioplasty and treatment with either scrambled peptide or LR12, an inhibitor of triggering receptor expressed on myeloid cell (TREM)-1, were compared between the experimental groups and with contralateral carotid artery. The results of this study elucidated the presence of OSM and p27KIP1 in carotid arteries with plaque and their association with arterial plaque and vulnerability. The findings suggest that targeting OSM and p27KIP1 axis regulating VSMC proliferation may have therapeutic significance to stabilize plaque.