Dysfunction In Human Umbilical Vein Endothelial Cells Research Articles

Notoginsenoside Fc alleviates oxidized low-density lipoprotein-induced endothelial cell dysfunction and upregulates PPAR-γ in vitro.

Deep venous thrombosis (DVT) is a prevalent vascular disease and a major cause of morbidity and mortality worldwide. Notoginsenoside Fc (NFc) is a protopanaxadiol-type saponin that has been shown to have beneficial effects on several disorders. However, its function in DVT is unclear. Human umbilical vein endothelial cells (HUVECs) were treated with oxidized low-density lipoprotein (ox-LDL) to mimic DVT in vitro and treated with NFc to investigate its functions. CCK-8 assay was utilized for measuring cell viability. Western blotting was used for detecting protein levels of proinflammatory cytokines, apoptosis-related markers, and peroxisome proliferator-activated receptor-γ (PPAR-γ). Flow cytometry was performed for cell apoptosis detection. Levels of oxidative stress-related markers were examined by the DCFH-DA method and ELISA. RT-qPCR was utilized for the measurement of PPAR-γ mRNA level. NFc increased the viability and suppressed inflammation, apoptosis, and oxidative stress in ox-LDL-treated HUVECs. NFc treatment induced upregulation of PPAR-γ in HUVECs. NFc mitigates ox-LDL-induced dysfunction of HUVECs.

MiR-21-Mediated Endothelial Senescence and Dysfunction Are Involved in Cigarette Smoke-Induced Pulmonary Hypertension through Activation of PI3K/AKT/mTOR Signaling.

Smoking is a pathogenic factor for pulmonary hypertension (PH). Our previous study showed that serum miR-21 levels are elevated in smokers. miR-21 is considered as engaged in the PH process; however, its mechanisms remain unclear. In this investigation, we found that in the lung tissue of smoking-induced PH patients, the levels of miR-21 and aging markers (p21 and p16) were upregulated, and the function of pulmonary vascular endothelial cells was also impaired. Exposure of mice to cigarette smoke (CS) for four months caused similar changes in lung tissues and increased pulmonary arterial pressure, which were attenuated by knockout of miR-21. Further, human umbilical vein endothelial cells (HUVECs) exposed to cigarette smoke extract (CSE) revealed upregulation of miR-21 levels, depression of PTEN, activation of PI3K/AKT/mTOR signaling, an increase in senescence indexes, and enhanced dysfunction. Inhibiting miR-21 overexpression reversed the PTEN-mTOR signaling pathway and prevented senescence and dysfunction of HUVECs. In sum, our data indicate that miR-21-mediated endothelial senescence and dysfunction are involved in CS-induced PH through the activation of PI3K/AKT/mTOR signaling, which suggests that selective miR-21 inhibition offers the potential to attenuate PH.

Circ_0002331 Interacts with ELAVL1 to Improve ox-LDL-Induced Vascular Endothelial Cell Dysfunction via Regulating CCND2 mRNA Stability.

Circular RNAs (circRNAs) have been discovered to serve as vital regulators in atherosclerosis (AS). However, the role and mechanism of circ_0002331 in AS process arestill unclear. Human umbilical vein endothelial cells (HUVECs) were treated with ox-LDL to establish an in vitro model for AS. The expression levels of circ_0002331, Cyclin D2 (CCND2) and ELAVL1 were analyzed by quantitative real-time PCR. Cell proliferation, apoptosis, migration, invasion and angiogenesis were assessed by EdU assay, flow cytometry, transwell assay and tube formation assay. The protein levels of CCND2, ELAVL1, and autophagy-related markers were detected using western blot analysis. IL-8 level was analyzed by ELISA. The relationship between ELAVL1 and circ_0002331 or CCND2 was analyzed by RIP assay and RNA pull-down assay. Moreover, FISH assay was used to analyze the co-localization of ELAVL1 and CCND2 in HUVECs. Our data showed that circ_0002331 was obviously downregulated in AS patients and ox-LDL-induced HUVECs. Overexpression of circ_0002331 could promote proliferation, migration, invasion and angiogenesis, while inhibit apoptosis, autophagy and inflammation in ox-LDL-induced HUVECs. Furthermore, CCND2 was positively regulated by circ_0002331, and circ_0002331 could bind with ELAVL1 to promote CCND2 mRNA stability. Besides, CCND2 overexpression suppressed ox-LDL-induced HUVECs dysfunction, and its knockdown also reversed the regulation of circ_0002331 on ox-LDL-induced HUVECs dysfunction. In conclusion, circ_0002331 might be a potential target for AS treatment, which could improve ox-LDL-induced dysfunction of HUVECs via regulating CCND2 by binding with ELAVL1.

Low shear stress-induced blockage of autophagic flux impairs endothelial barrier and facilitates atherosclerosis in mice

Atherosclerosis preferentially occurs in areas with low shear stress (LSS) and oscillatory flow. LSS has been demonstrated to correlate with the development of atherosclerosis. The sphingosine 1-phosphate receptor 1 (S1PR1), involving intravascular blood flow sensing, regulates vascular development and vascular barrier function. However, whether LSS affects atherosclerosis via regulating S1PR1 remains incompletely clear. In this study, immunostaining results of F-actin, β-catenin, and VE-cadherin indicated that LSS impaired endothelial barrier function in human umbilical vein endothelial cells (HUVECs). Western blot analysis showed that LSS resulted in blockage of autophagic flux in HUVECs. In addition, autophagy agonist Rapamycin (Rapa) antagonized LSS-induced endothelial barrier dysfunction, whereas autophagic flux inhibitor Bafilomycin A1 (BafA1) exacerbated it, indicating that LSS promoted endothelial barrier dysfunction by triggering autophagic flux blockage. Notably, gene expression analysis revealed that LSS downregulated S1PR1 expression, which was antagonized by Rapa. Selective S1PR1 antagonist W146 impaired endothelial barrier function of HUVECs under high shear stress (HSS) conditions. Moreover, our data showed that expression of GAPARAPL2, a member of autophagy-related gene 8 (Atg8) proteins, was decreased in HUVECs under LSS conditions. Autophagic flux blockage induced by GAPARAPL2 knockdown inhibited S1PR1, aggravated endothelial barrier dysfunction of HUVECs in vitro, and promoted aortic atherosclerosis in ApoE−/− mice in vivo. Our study demonstrates that autophagic flux blockage induced by LSS downregulates S1PR1 expression and impairs endothelial barrier function. GABARAPL2 inhibition is involved in LSS-induced autophagic flux blockage, which impairs endothelial barrier function via downregulation of S1PR1.

NLRC4-mediated pyroptosis was involved in coagulation disorders of acute pancreatitis.

Acute pancreatitis (AP) is a potentially lethal acute disease highly involved in coagulation disorders. Pyroptosis has been reported to exacerbate coagulation disorders, yet this implication has not been illustrated completely in AP. RNA sequencing data of peripheral blood of AP patients were downloaded from the Gene Expression Omnibus database. Gene set variation analysis and single sample gene set enrichment analysis were used to calculate the enrichment score of coagulation-related signatures and pyroptosis. Spearman and Pearson correlation analysis was used for correlation analysis. Peripheral blood samples and related clinical parameters were collected from patients with AP and healthy individuals. A severe AP (SAP) model of mice was established using caerulein and lipopolysaccharide. Enzyme-linked immunosorbent assay, chemiluminescence immunoassay and immunohistochemical analysis were employed to detect the level of coagulation indicators and pyroptosis markers in serum and pancreas tissues. Additionally, we evaluated the effect of pyroptosis inhibition and NLRC4 silence on the function of human umbilical vein endothelial cells (HUVECs). Coagulation disorders were significantly positively correlated to the severity of AP, and they could be a predictor for AP severity. Further analyses indicated that six genes-DOCK9, GATA3, FCER1G, NLRC4, C1QB and C1QC-may be involved in coagulation disorders of AP. Among them, NLRC4 was positively related to pyroptosis that had a positive association with most coagulation-related signatures. Data from patients showed that NLRC4 and other pyroptosis markers, including IL-1β, IL-18, caspase1 and GSDMD, were significant correlation to AP severity. In addition, NLRC4 was positively associated with coagulation indicators in AP patients. Data from mice showed that NLRC4 was increased in the pancreas tissues of SAP mice. Treatment with a pyroptosis inhibitor effectively alleviated SAP and coagulation disorders in mice. Finally, inhibiting pyroptosis or silencing NLRC4 could relieve endothelial dysfunction in HUVECs. NLRC4-mediated pyroptosis damages the function of endothelial cells and thereby exacerbates coagulation disorders of AP. Inhibiting pyroptosis could improve coagulation function and alleviate AP.

MiR-497-5p regulates ox-LDL-induced dysfunction in vascular endothelial cells by targeting VEGFA/p38/MAPK pathway in atherosclerosis

BackgroundThe impairment of endothelial cells triggered by oxidized low-density lipoprotein (ox-LDL) stands as a critical event in the advancement of atherosclerosis (AS). MiR-497-5p has been recognized as a potential predictor for AS, but its precise involvement in ox-LDL-induced endothelial cell dysfunction remains to be elucidated. MethodsAn in vitro AS cell model was established by exposing human umbilical vein endothelial cells (HUVECs) to 100 μg/mL ox-LDL for 24 h. The assessment of endothelial cell function included evaluating cell viability, caspase-3 activity, inflammatory factors, and oxidative markers. Molecular mechanisms were elucidated through quantitative real-time PCR, Western blot analysis, and luciferase reporter assays. ResultsOur investigation revealed that exposure to ox-LDL led to an upregulation in miR-497-5p and p-p38 levels, while downregulating the expression of vascular endothelial growth factor A (VEGFA) and phosphorylated (p)-endothelial nitric oxide synthase (p-eNOS) in HUVECs. Ox-LDL exposure resulted in decreased cell viability and angiogenic capacity, coupled with increased apoptosis, inflammation, and oxidative stress in HUVECs, partially mediated by the upregulation of miR-497-5p. We confirmed VEGFA as a direct target of miR-497-5p. Interfering with VEGFA expression significantly reversed the effects mediated by miR-497-5p silencing in HUVECs exposed to ox-LDL. ConclusionsIn summary, our findings demonstrate that miR-497-5p exacerbates ox-LDL-induced dysfunction in HUVECs through the activation of the p38/MAPK pathway, mediated by the targeting of VEGFA.

IGF2BP3 stabilizes SESN1 mRNA to mitigate oxidized low-density lipoprotein-induced oxidative stress and endothelial dysfunction in human umbilical vein endothelial cells by activating Nrf2 signaling

Atherosclerosis (AS) represents a prevalent initiating factor for cardiovascular events. Insulin-like growth factor 2 mRNA binding protein 3 (IGF2BP3) is an oncofetal RNA-binding protein that participates in cardiovascular diseases. This work aimed to elaborate the effects of IGF2BP3 on AS and the probable mechanism by using an oxidized low-density lipoprotein (ox-LDL)-induced human umbilical vein endothelial cells (HUVECs) model. Results indicated that IGF2BP3 expression was declined in the blood of AS patients and ox-LDL-induced HUVECs. IGF2BP3 elevation alleviated ox-LDL-provoked viability loss, apoptosis, oxidative DNA damage and endothelial dysfunction in HUVECs. Moreover, IGF2BP3 bound SESN1 and stabilized SESN1 mRNA. Furthermore, SESN1 interference reversed the impacts of IGF2BP3 overexpression on the apoptosis, oxidative DNA damage and endothelial dysfunction of ox-LDL-challenged HUVECs. Additionally, the activation of Nrf2 signaling mediated by IGF2BP3 up-regulation in ox-LDL-treated HUVECs was blocked by SESN1 absence. Collectively, SESN1 stabilized by IGF2BP3 might protect against AS by activating Nrf2 signaling.

Upregulation of TRPC1 protects against high glucose-induced HUVECs dysfunction by inhibiting oxidative stress

—To explore the effect of TRPC1 on endothelial cell function damage under a high glucose environment and its downstream molecular mechanism, and provide new theory and strategy for improving diabetic endothelial cell function and promoting vascular injury repair. In vitro, we use high glucose to treat human umbilical vein endothelial cells (HUVECs) and upregulated TRPC1 with adenovirus infection. HUVECs were split into 4 groups: (i) NG Group: Treated with normal glucose; (ii) HG Group: Treated with high glucose; (iii) HG + adGFP Group: High glucose + the control adenovirus (adGFP); (iv) HG + adTRPC1 Group: High glucose + recombinant adenovirus encoding TRPC1. We found that high glucose significantly decreased the expression level of TRPC1 protein, and impaired the proliferation and migration of HUVECs, which could be reversed by overexpression of TRPC1. In addition, high glucose induced an increase in ROS and MDA and a decrease in SOD activity, whereas TRPC1 overexpression could inhibit the growth of oxidative stress level. These findings suggest that overexpression of TRPC1 prevents HUVECs proliferation and migration dysfunction induced by high glucose via inhibiting oxidative stress injuries.

Specific role of NAD+ biosynthesis reduction mediated mitochondrial dysfunction in vascular endothelial injury induced by chronic intermittent hypoxia.

Cardiovascular diseases (CVD) are prevalent among those with obstructive sleep apnea (OSA) and are the leading cause of death in these individuals. However, due to clinical confounders, the mechanism by which OSA induces CVD is still unclear. Previous studies have shown that chronic intermittent hypoxia (CIH) and high cholesterol diet (HCD) induce distinct characteristics of atherosclerotic plaques, highlighting the specific mechanisms involved in CIH-induced vascular endothelial injury. This study aims to investigate whether nicotinamide adenine dinucleotide (NAD+) biosynthesis reduction-mediated mitochondrial dysfunction is responsible for vascular endothelial injury induced by CIH and to elucidate its specific role in this process. Models were established to stimulate human umbilical vein endothelial cells (HUVECs) with CIH and oxidized low-density lipoprotein (ox-LDL), and the NAD+ biosynthesis-related indicators, such as NAD+ levels and nicotinamide phosphoribosyltransferase (NAMPT) enzyme activity, were measured in this model. Additionally, interventions were performed by supplementing NAD+ levels with nicotinamide mononucleotide (NMN), inhibiting NAD+ synthesis with FK866, and evaluating mitochondrial function, oxidative stress status, vascular constriction and dilation function, and endothelial adhesion function in these models. A comparative study was conducted to assess the effects of these interventions. We found that under CIH conditions, NAMPT enzyme activity was inhibited, leading to a reduction in NAD+ biosynthesis and a decrease in NAD+/NADH ratio. At the same time, CIH caused mitochondrial dysfunction in HUVECs, including a decrease in adenosine triphosphate (ATP) content and mitochondrial membrane potential, as well as the activity of respiratory chain complex I and III, induced an increase in oxidative stress levels in endothelial cells, impaired vascular constriction and dilation function, and significantly increased expression of adhesion factors. The impact of CIH on endothelial cell-related mitochondrial function and endothelial function was restored by supplementing NMN. Although ox-LDL also causes multi-level endothelial injury, it does not involve the NAD+ pathway, as there were no significant changes in the related indicators, and the impaired endothelial function under ox-LDL conditions was not restored by supplementing NMN. CIH-induced vascular endothelial injury may be associated with NAD+ biosynthesis reduction-mediated mitochondrial dysfunction. Supplementing NAD+ precursors to increase its levels may be a potential intervention to ameliorate CIH-induced vascular endothelial injury, while it does not have a significant effect on endothelial injury caused by ox-LDL.

Src kinase partially mediates cytokine-induced endothelial dysfunction

ObjectivesEndothelial dysfunction is known to be a key characteristic of preeclampsia (PE) and can contribute to progression of symptoms and injury to multiple organ systems. Delivery is the only treatment for progression of PE, but development of an endothelial-based therapy for PE presents a promising strategy. Growth factors and cytokines are dysregulated in PE and can impact endothelial function, manifesting changes in Ca2+ signaling and interruptions in monolayer barrier function that contribute to symptoms of hypertension, proteinuria, and edema. In this study, we highlight Src kinase as a partial mediator of growth factor and cytokine mediated endothelial dysfunction. Study designFura-2 Ca2+ imaging and Electrical Cell Impedance Sensing (ECIS) assays are performed on growth factor or cytokine exposed human umbilical vein endothelial cells (HUVECs). Inhibitors to MEK/ERK (U0126) or Src (PP2) are used to determine the contribution of kinase signaling pathways. Main outcome measuresDecreases in HUVEC Ca2+ signaling or monolayer resistance measure endothelial dysfunction. Reversal of endothelial dysfunction by kinase inhibitors reveals the respective contibutions of MEK/ERK and Src kinase. ResultsWe show that Src inhibition protects Ca2+ signaling responses against insults induced by VEGF165, bFGF, PlGF, TNFα, and IL-1β. Additionally, we show that Src inhibition protects the endothelial monolayer from the full impact of TNFα insult. Further, we find that MEK/ERK inhibition does not offer protection from growth factor-mediated endothelial dysfunction. ConclusionsThe results of this study suggest cytokine and growth factor-stimulated Src kinase plays a partial role on promoting endothelial dysfunction in HUVECs.

CTRP13 alleviates palmitic acid-induced inflammation, oxidative stress, apoptosis and endothelial cell dysfunction in HUVECs

C1q/tumor necrosis factor-related protein 13 (CTRP13) has been reported to participate in cardiovascular diseases. However, the role and molecular mechanism of CTRP13 in obesity-induced endothelial cell damage is still unclear. In palmitic acid (PA)-induced human umbilical vein endothelial cells (HUVECs), qRT-PCR and western blot were used to examine CTRP13 expression. CCK-8 and TUNEL assays were adopted to assess cell viability and apoptosis, respectively. ROS level and MDA content were evaluated by their commercial kits and inflammatory cytokines were measured using ELISA. Endothelial cell dysfunction was evaluated by detecting NO production and eNOS expression, and tube formation assay was performed to assess angiogenesis. AMPK pathway-related proteins were detected by western blot. The results showed that CTRP13 was downregulated in PA-induced HUVECs. CTRP13 overexpression reduced PA-induced cell viability loss and oxidative stress in HUVECs. Moreover, CTRP13 overexpression suppressed PA-induced inflammation and apoptosis, improved angiogenesis ability, and alleviated endothelial cell dysfunction in HUVECs. In addition, CTRP13 overexpression activated AMPK pathway and regulated the expressions of downstream NOX1/p38 and KLF2. Furthermore, compound C countervailed the impacts of CTRP13 overexpression on cell viability, oxidative stress, inflammation, apoptosis and endothelial function in PA-induced HUVECs. To sum up, CTRP13 overexpression may alleviate PA-induced endothelial cell damage.

Human umbilical cord mesenchymal stem cell derived exosomes (HUCMSC-exos) recovery soluble fms-like tyrosine kinase-1 (sFlt-1)-induced endothelial dysfunction in preeclampsia

BackgroundPreeclampsia is a unique multisystem disorder that affects 5–8% of pregnancies. A high level of soluble fms-like tyrosine kinase-1 (sFlt-1) is a hallmark of preeclampsia that causes endothelial dysfunction. Exosomes derived from mesenchymal stem cells (MSCs) have been indicated to improve endothelial performances by transporting signals to target cells. We hypothesized that exosomes derived from MSCs have potential effects against preeclampsia.MethodsWe collected human umbilical cord MSC-derived exosomes (HUCMSC-exos) by ultracentrifugation. The size and morphology of the exosomes were examined using a transmission electron microscope and nanoparticle tracking analysis. Pregnant mice were injected with murine sFlt-1 adenovirus to build the preeclampsia-like mouse model and then treated with HUCMSC-exos. Human umbilical vein endothelial cells (HUVECs) were infected with lentiviruses expressing tet-on-sFlt-1 to obtain cells overexpressing sFlt-1. Cell proliferation and migration assays were used to measure the endothelial functions. The exosomes enriched proteins underlying mechanisms were explored by proteomic analysis.ResultsIn the current study, we successfully collected the cup-shaped HUCMSC-exos with diameters of 30–150 nm. In the sFlt-1-induced preeclampsia mouse model, HUCMSC-exos exhibited beneficial effects on adverse birth events by decreasing blood pressure and improving fetal birth weight. In addition, preeclamptic dams that were injected with HUCMSC-exos had rebuilt dense placental vascular networks. Furthermore, we observed that HUCMSC-exos partially rescued sFlt-1-induced HUVECs dysfunction in vitro. Proteomics analysis of HUCMSC-exos displayed functional enrichment in biological processes related to vesicle-mediated transport, cell communication, cell migration, and angiogenesis.ConclusionWe propose that exosomes derived from HUCMSCs contain abundant Versican and play beneficial roles in the birth outcomes of sFlt-1-induced preeclamptic mice by promoting angiogenesis.Graphical

FGFR2 modulates the Akt/Nrf2/ARE signaling pathway to improve angiotensin II-induced hypertension-related endothelial dysfunction

ABSTRACT Background Fibroblast growth factor receptor (FGFR)2 expression was decreased in hypertension patients while its role in hypertension was not explored. This experiment aimed to investigate the expression ofFGFR2 in angiotensin II (Ang II)-induced human umbilical vein endothelial cells (HUVECs) and the role of FGFR2 in improving AngII-induced hypertension-related endothelial dysfunction. Methods AngII-induced HUVECs simulated the hypertension model in vitro. The expression of FGFR2 in Ang II-induced HUVECs and transfected HUVECswas detected by RT-qPCR and western blot. The viability, apoptosis, migration and tube formation ability of Ang II-induced HUVECs were analyzed by Methyl Thiazolyl Tetrazolium (MTT) assay, flow cytometry analysis, wound healing assay and tube formation assay.Detectionof lactate dehydrogenase (LDH), caspase 3, Nitric Oxide (NO) and oxidative stress levels was conducted by assay kits and reactive oxygen species (ROS) level was detected by DCFH-DA assay. The expression of apoptosis-related proteins, protein kinase B(Akt)/nuclear factor E2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway-related proteins, phospho(p)-endothelial nitric oxide synthase (eNOS) and eNOS was determined by western blot. Results The expression of FGFR2 was decreased in Ang II-induced HUVECs. FGFR2overexpression increased viability, suppressed apoptosis and oxidative stress, and improve endothelial dysfunction of AngII-induced HUVECs through activating the Akt/Nrf2/ARE signaling pathway. MK-2206 (Akt inhibitor) could weaken the effect of FGFR2overexpression to reduce viability, promote apoptosis and oxidative stress, and aggravate endothelial dysfunction of Ang II-inducedHUVECs. Conclusion Inconclusion, FGFR2activated the Akt/Nrf2/ARE signaling pathway to improve AngII-induced hypertension-related endothelial dysfunction.

The Potential Role of MiRs-139-5p and -454-3p in Endoglin-Knockdown-Induced Angiogenic Dysfunction in HUVECs

Hereditary hemorrhagic telangiectasia (HHT) is a rare genetic disease characterized by aberrant angiogenesis and vascular malformations. Mutations in the transforming growth factor beta co-receptor, endoglin (ENG), account for approximately half of known HHT cases and cause abnormal angiogenic activity in endothelial cells (ECs). To date, how ENG deficiency contributes to EC dysfunction remains to be fully understood. MicroRNAs (miRNAs) regulate virtually every cellular process. We hypothesized that ENG depletion results in miRNA dysregulation that plays an important role in mediating EC dysfunction. Our goal was to test the hypothesis by identifying dysregulated miRNAs in ENG-knockdown human umbilical vein endothelial cells (HUVECs) and characterizing their potential role in EC function. We identified 32 potentially downregulated miRNAs in ENG-knockdown HUVECs with a TaqMan miRNA microarray. MiRs-139-5p and -454-3p were found to be significantly downregulated after RT-qPCR validation. While the inhibition of miR-139-5p or miR-454-3p had no effect on HUVEC viability, proliferation or apoptosis, angiogenic capacity was significantly compromised as determined by a tube formation assay. Most notably, the overexpression of miRs-139-5p and -454-3p rescued impaired tube formation in HUVECs with ENG knockdown. To our knowledge, we are the first to demonstrate miRNA alterations after the knockdown of ENG in HUVECs. Our results indicate a potential role of miRs-139-5p and -454-3p in ENG-deficiency-induced angiogenic dysfunction in ECs. Further study to examine the involvement of miRs-139-5p and -454-3p in HHT pathogenesis is warranted.

Circ_0026218 ameliorates oxidized low-density lipoprotein-induced vascular endothelial cell dysfunction by regulating miR-188-3p/TLR4/NF-κB pathway.

Circular RNAs (circRNAs) have shown important regulatory roles in cardiovascular diseases, including atherosclerosis (AS). However, the role and mechanism of circ_0026218 in AS remain unclear. The cell model of AS in vitro was established by stimulating human umbilical vein endothelial cells (HUVECs) with oxidized low-density lipoprotein (ox-LDL). In addition, circ_0026218, microRNA-188-3p (miR-188-3p), and toll-like receptor 4 (TLR4) expression was determined via real-time quantitative polymerase chain reaction (RT-qPCR) in serum samples from AS patients and healthy volunteers. Cell proliferation was assessed using Cell Counting Kit-8 (CCK-8) assay and 5-ethynyl-2'-deoxyuridine (EdU) assay. Cell apoptosis was measured using flow cytometry. The inflammatory response was assessed using enzyme-linked immunosorbent assay (ELISA). Oxidative stress level was assessed using corresponding kits. Nitric oxide (NO) level was examined using NO detection assay. The interaction between miR-188-3p and circ_0026218 or TLR4 was determined via dual-luciferase reporter, RNA immunoprecipitation (RIP), and RNA pull-down assays. Exosomes were observed using transmission electron microscopy (TEM). The size distribution of exosomes was analyzed using nanoparticle tracking analysis (NTA). Ox-LDL treatment caused HUVEC dysfunction by inhibiting cell proliferation and promoting apoptosis, inflammation, and oxidative stress. Circ_0026218 was upregulated in AS serum samples and ox-LDL-treated HUVECs. Knockdown of circ_0026218 attenuated ox-LDL-induced dysfunction in HUVECs. MiR-188-3p acted as a target of circ_0026218, and miR-188-3p downregulation reversed the suppression role of circ_0026218 knockdown on ox-LDL-induced HUVEC disorder. TLR4 was a target of miR-188-3p, and miR-188-3p overexpression alleviated ox-LDL-induced dysfunction in HUVECs by targeting TLR4. Circ_0026218 could deregulate the TLR4/NF-κB pathway by sponging the miR-188-3p. Importantly, circ_0026218 was overexpressed in exosomes from ox-LDL-treated HUVECs and could be delivered via exosomes. Circ_0026218 knockdown attenuated ox-LDL-induced dysfunction in HUVECs via regulating miR-188-3p/TLR4/NF-κB pathway.

M6A-related bioinformatics analysis and functional characterization reveals that METTL3-mediated NPC1L1 mRNA hypermethylation facilitates progression of atherosclerosis via inactivation of the MAPK pathway.

Accumulating evidence has demonstrated that N6-methyladenosine (m6A) plays important roles in many major diseases, including atherosclerosis (AS). In the present study, we aimed to explore the transcriptomic m6A landscape of endothelial function-associated genes and identify potential regulators in AS progression. The GEO data (GSE142386) from MeRIP-seq in human umbilical vein endothelial cells (HUVECs) with METTL3 knocked down or not were analyzed. RNA-seq was performed to identify differences in gene expression. Gene ontology (GO) functional and Kyoto encyclopedia of genes and genomes (KEGG) pathway analyses were conducted to evaluate the potential functions of the differentially expressed genes. MeRIP-qPCR was used to measure the m6A and mRNA levels of the top 8 downregulated genes, and NPC1L1 was selected as the candidate gene. Oxidized low-density lipoprotein (ox-LDL) was used to stimulate HUVECs, and METTL3 or NPC1L1 was silenced in ox-LDL-treated cells. And Transwell, ELISA, and cell apoptosis assays were performed to assess cell functional injury. ApoE-/- mice were fed with high-fat diet for 8 weeks to establish an AS model, and adenovirus-mediated NPC1L1 shRNA or NC shRNA was injected into the mice through the tail vein. Mouse aortic tissue damage and plaque deposition were evaluated by H&E, Oil Red O, and TUNEL staining. One hundred and ninety-four hypermethylated m6A peaks and 222 hypomethylated peaks were detected in response to knockdown of METTL3. Genes with altered m6A peaks were significantly involved in the histone modification, enzyme activity, and formation of multiple complexes and were predominantly enriched in the MAPK pathway. NPC1L1 was a most significantly downregulated transcript in response to knockdown of METTL3. Moreover, knockdown of NPC1L1 or de-m6A (METTL3 knockdown)-mediated downregulation of NPC1L1 could improve ox-LDL-induced dysfunction of HUVECs in vitro and high-fat diet-induced atherosclerotic plaque in vivo, which was associated with the inactivation of the MAPK pathway. METTL3-mediated NPC1L1 mRNA hypermethylation facilitates AS progression by regulating the MAPK pathway, and NPC1L1 may be a novel target for the treatment of AS.

MiR-216b-5p regulates proliferation and apoptosis of ox-LDL-stimulated VSMCs and HUVECs via IGF2.

Atherosclerosis (AS) is one of the principal causes of cardiovascular disorder. Reportedly, vascular smooth muscle cells (VSMCs) and human umbilical vein endothelial cells (HUVECs) play key roles in AS development, and microRNAs (miRNAs) regulate their functions. The function of miR-216b-5p in AS remains unknown. Human VSMCs and human HUVECs were treated with ox-LDL to establish the in vitro model of AS. MiR-216b-5p and IGF2 expressions in VSMCs and HUVECs were probed by qRT-PCR and western blot. The viability, cell cycle progression, and apoptosis of VSMCs and HUVECs were evaluated by Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine, and flow cytometry assays, respectively. The binding sites between IGF2 3'UTR and miR-216b-5p were validated by dual-luciferase reporter assay. miR-216b-5p expression was declined in ox-LDL-induced VSMCs and HUVECs. In VSMCs, miR-216b-5p overexpression inhibited excessive proliferation and induced apoptosis. MiR-216b-5p could markedly restrain the viabiblity of VSMCs induced by ox-LDL and enhanced the viability of HUVECs. Additionally, IGF2 was confirmed as the direct target of miR-216b-5p and transfection of IGF2 overexpression plasmids rescued the effects of miR-216b-5p on VSMCs and HUVECs. miR-216b-5p alleviates the dysfunction of VSMCs and HUVECs caused by ox-LDL via repressing IGF2, and exerts protective functions to block the development of AS.

Acrolein evokes inflammation and autophagy-dependent apoptosis through oxidative stress in vascular endothelial cells and its protection by 6-C-(E-2-fluorostyryl)naringenin

• Acrolein induced mitochondrial dysfunction, apoptosis, and inflammation in HUVECs. • Acrolein induced apoptosis was partially dependent on the activation of autophagy. • The addition of styryl group contributed to the protective potential of 6- C -( E -fluorostyryl)naringenin. • The protective effects of 6- C -( E -fluorostyryl)naringenin is via Nrf2 activation. Acrolein is a common dietary and environmental toxicant. Evidence suggests that acrolein can increase the risk of cardiovascular diseases in which endothelial cells are the sensitive targets. In human umbilical vein endothelial cells (HUVECs), acrolein treatment induced mitochondrial dysfunction, which subsequently triggered apoptosis and inflammation. Acrolein also upregulated autophagy, which possibly resulted from negative regulation of the protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway via reactive oxygen species (ROS). Inhibition of autophagy by 3-methyladenine reduced acrolein-evoked apoptosis, implying a pro-death role of autophagy. In addition, the protective potential of 6- C -( E -2-fluorostyryl)naringenin (6-CEFN) against acrolein was examined. 6-CEFN exhibited higher efficacy than its parental compound naringenin in preventing acrolein-caused damages, where nuclear factor erythroid 2-related factor (Nrf2)-mediated up-regulation of phase II enzymes was involved. Altogether, our findings offer new mechanistic insights into acrolein-induced endothelial injury and demonstrate the therapeutic potential of 6-CEFN for acrolein-related cardiovascular toxicities.

Umbelliferone protects against methylglyoxal-induced HUVECs dysfunction through suppression of apoptosis and oxidative stress.

Methylglyoxal (MGO), a cytotoxic metabolite of glycolysis, can cause endothelial cells impairment, which is tightly associated with diabetic vascular complication. Umbelliferone, a derivative of coumarin, participates in various pharmacological activities. This study aimed to determine the effectiveness of umbelliferone in MGO-induced apoptosis and oxidative stress in endothelial cells. In this study, it has been indicated that umbelliferone inhibited MGO-induced human umbilical vein endothelial cells (HUVECs) cytotoxicity, apoptosis, Bax/Bcl-2 protein ratio, the activity of cleaved-caspase-3, and mitochondrial membrane potential loss. Furthermore, we found that umbelliferone inhibited MGO-induced activation of mitogen-activated protein kinases and nuclear factor-κB signaling pathways in HUVECs. In addition, umbelliferone could suppress oxidative stress, as evidenced by decrease of reactive oxygen species and malondialdehyde (MDA) generation, and increase of superoxide dismutase and glutathione peroxidase contents. Moreover, we found that umbelliferone can activate Nrf2/HO-1 signaling. Importantly, silencing of Nrf2 signaling clearly eliminated the anti-oxidative stress of umbelliferone, whereas umbelliferone pretreatment had no effect on Nrf2 overexpressing HUVECs. Altogether, this study suggested that umbelliferone pretreatment has a protective effect on MGO-induced endothelial cell dysfunction through inhibiting apoptosis and oxidative stress.

Perfluorooctane Sulfonate Induces Dysfunction of Human Umbilical Vein Endothelial Cells via Ferroptosis Pathway.

(1) Background: Perfluorooctane sulfonate (PFOS) is a persistent organic pollutant, and it is receiving increasing attention regarding its human health risks due to its extensive use. Endothelial dysfunction is a mark of cardiovascular disease, but the basic mechanism of PFOS-induced endothelial dysfunction is still not fully understood. Ferroptosis is a newly defined regulatory cell death driven by cellular metabolism and iron-dependent lipid peroxidation. Although ferroptosis has been shown to be involved in the pathogenesis of cardiovascular diseases, the involvement of ferroptosis in the pathogenesis of endothelial dysfunction caused by PFOS remains unclear. (2) Purpose: To explore the role of ferroptosis in the dysfunction of endothelial cells and underlying mechanisms. (3) Methods: Human umbilical vein endothelial cells (HUVECs) were exposed to PFOS or PFOS and Fer-1. The viability, morphology change under electronic microscope, lipid-reactive oxygen species (lipid-ROS), and production of nitric oxide (NO) were determined. The expression of glutathione peroxidase 4(GPX4), ferritin heavy chain protein 1 (FTH1), heme oxygenase 1 (HO-1) and Acyl-CoA synthetase long-chain family member 4 (ACSL4) were analyzed via Western blot analysis. (4) Results: PFOS was shown to cause a decrease in viability and morphological changes of mitochondria, and well as an increase in lipid droplets. The expression of GPX4, FTH1 and HO-1 was decreased, and that of ACSL4 was increased after exposure to PFOS. In addition to the above-mentioned ferroptosis-related manifestations, there was also a reduction in NO content. (5) Conclusions: PFOS induces ferroptosis by regulating the GPX4 and ACSL4 pathways, which leads to HUVEC dysfunction.