scholarly journals RNA N6-methyladenosine modulates endothelial atherogenic responses to disturbed flow in mice

eLife ◽  
2022 ◽  
Vol 11 ◽  
Author(s):  
Bochuan Li ◽  
Ting Zhang ◽  
Mengxia Liu ◽  
Zhen Cui ◽  
Yanhong Zhang ◽  
...  
Keyword(s):  
Umbilical Vein ◽  
Vascular Inflammation ◽  
Double Mutation ◽  
Disturbed Flow ◽  
Atherosclerosis Progression ◽  
Functional Studies ◽  
Egfr Signaling Pathway ◽  
Egfr Activation ◽  
Atherosclerotic Process ◽  
Umbilical Vein Endothelial Cells

Atherosclerosis preferentially occurs in atheroprone vasculature where human umbilical vein endothelial cells (HUVECs) are exposed to disturbed flow. Disturbed flow is associated with vascular inflammation and focal distribution. Recent studies have revealed the involvement of epigenetic regulation in atherosclerosis progression. N6-methyladenosine (m6A) is the most prevalent internal modification of eukaryotic mRNA, but its function in endothelial atherogenic progression remains unclear. Here, we show that m6A mediates the EGFR signaling pathway during EC activation to regulate the atherosclerotic process. Oscillatory stress (OS) reduced the expression of METTL3, the primary m6A methyltransferase. Through m6A sequencing and functional studies, we determined that m6A mediates the mRNA decay of the vascular pathophysiology gene EGFR which leads to EC dysfunction. m6A modification of the EGFR 3'UTR accelerated its mRNA degradation. Double mutation of the EGFR 3'UTR abolished METTL3-induced luciferase activity. Adenovirus-mediated METTL3 overexpression significantly reduced EGFR activation and endothelial dysfunction in the presence of OS. Furthermore, TSP-1, an EGFR ligand, was specifically expressed in atheroprone regions without being affected by METTL3. Inhibition of the TSP-1/EGFR axis by using shRNA and AG1478 significantly ameliorated atherogenesis. Overall, our study revealed that METTL3 alleviates endothelial atherogenic progression through m6A-dependent stabilization of EGFR mRNA, highlighting the important role of RNA transcriptomics in atherosclerosis regulation.

scholarly journals Dihydromyricetin Attenuates TNF-α-Induced Endothelial Dysfunction through miR-21-Mediated DDAH1/ADMA/NO Signal Pathway

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Dafeng Yang ◽  
Shenglan Tan ◽  
Zhousheng Yang ◽  
Pei Jiang ◽  
Caie Qin ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Endothelial Dysfunction ◽  
Umbilical Vein ◽  
Underlying Mechanism ◽  
Tube Formation ◽  
Signal Pathway ◽  
Dependent Manner ◽  
Necrosis Factor Alpha ◽  
Atherosclerotic Process ◽  
Umbilical Vein Endothelial Cells

Accumulating studies demonstrate that dihydromyricetin (DMY), a compound extracted from Chinese traditional herb, Ampelopsis grossedentata, attenuates atherosclerotic process by improvement of endothelial dysfunction. However, the underlying mechanism remains poorly understood. Thus, the aim of this study is to investigate the potential mechanism behind the attenuating effects of DMY on tumor necrosis factor alpha- (TNF-α-) induced endothelial dysfunction. In response to TNF-α, microRNA-21 (miR-21) expression was significantly increased in human umbilical vein endothelial cells (HUVECs), in line with impaired endothelial dysfunction as evidenced by decreased tube formation and migration, endothelial nitric oxide synthase (eNOS) (ser1177) phosphorylation, dimethylarginine dimethylaminohydrolases 1 (DDAH1) expression and metabolic activity, and nitric oxide (NO) concentration as well as increased asymmetric dimethylarginine (ADMA) levels. In contrast, DMY or blockade of miR-21 expression ameliorated endothelial dysfunction in HUVECs treated with TNF-α through downregulation of miR-21 expression, whereas these effects were abolished by overexpression of miR-21. In addition, using a nonspecific NOS inhibitor, L-NAME, also abrogated the attenuating effects of DMY on endothelial dysfunction. Taken together, these data demonstrated that miR-21-mediated DDAH1/ADMA/NO signal pathway plays an important role in TNF-α-induced endothelial dysfunction, and DMY attenuated endothelial dysfunction induced by TNF-α in a miR-21-dependent manner.

Abstract 181: BET Bromodomain Inhibition Suppresses Endothelial Inflammation and Atherosclerosis

2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Jonathan Brown ◽  
Qiong Duan ◽  
Gabriel Griffin ◽  
Ronald Paranal ◽  
Steven Bair ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Rna Polymerase Ii ◽  
Umbilical Vein ◽  
Ldl Receptor ◽  
Flow Chamber ◽  
Cancer Therapies ◽  
Functional Studies ◽  
Endothelial Inflammation ◽  
Umbilical Vein Endothelial Cells

Introduction The BET bromodomain-containing family of proteins (BRD2, BRD3, BRD4) are epigenetic readers that coactivate transcription. Recent evidence indicates that BETs promote carcinogenesis and inflammation in sepsis, while BET bromodomain inhibitors are promising anti-cancer therapies. However, the role of chromatin remodeling in atherosclerosis in general and through BETs in particular remains unknown. Hypothesis We hypothesized that BET bromodomain-containing proteins coactivate proinflammatory responses in the vasculature with functional effects that promote atherogenesis. Methods and Results BET bromodomain inhibition, achieved with the highly selective, small-molecule inhibitor JQ1 significantly reduced early atherosclerosis (12 weeks) in cholesterol-fed, LDL receptor-null mice. In pursuing mechanisms for this effect, we identified BET protein expression in mouse and human endothelial cells (ECs) as well as endothelium from human atherosclerotic plaque. Treating human umbilical vein endothelial cells (HUVECs) with either JQ1 or siRNA to BRD2 or BRD4 potently suppresses TNFα-induced expression of adhesion molecules (SELE, VCAM1) and chemokines (CCL2, CXCL8). In chromatin immunoprecipation studies, TNFα stimulation of ECs recruited BETs to adhesion molecule and chemokine promoters coincident with RNA polymerase II and cyclin T1 localization, without altering NF-κB recruitment. In functional studies, JQ1 suppressed 1) monocyte adhesion to TNFα-activated HUVECs, 2) leukocyte rolling on cremaster post-capillary venules (intravital microscopy); 3) leukocyte transmigration (parallel-plate flow chamber); and 4) monocyte recruitment in thioglycolate-induced peritonitis in vivo . Conclusions BET bromodomain-containing proteins are novel determinants of pro-inflammatory transcription in the endothelium. Targeting chromatin by BET bromodomain inhibition may be a therapeutic strategy to limit atherosclerosis and other disorders involving endothelial inflammation.

scholarly journals Bubbles Induce Endothelial Microparticle Formation via a Calcium-Dependent Pathway Involving Flippase Inactivation and Rho Kinase Activation

2018 ◽  
Vol 46 (3) ◽  
pp. 965-974 ◽  
Author(s):  
Xuhua Yu ◽  
Jiajun Xu ◽  
Wenwu Liu ◽  
Weigang Xu
Keyword(s):  
Kinase Inhibitor ◽  
Umbilical Vein ◽  
Vascular Inflammation ◽  
Cell Communication ◽  
Rho Kinase ◽  
Cytoplasmic Calcium ◽  
Kinase Substrate ◽  
Protein Levels ◽  
Underlying Mechanisms ◽  
Umbilical Vein Endothelial Cells

Background/Aims: Intravascular bubbles can exert pleiotropic detrimental effects, partly by inducing endothelial microparticles (EMPs) production, which play critical roles in cell communication and vascular inflammation cascades. However, the underlying mechanisms remain unclear. This study aimed to delineate the possible mechanisms involving bubble-induced EMPs formation. Methods: Human umbilical vein endothelial cells (HUVECs) were contacted by bubbles and EMPs level in supernatant were quantified by flow cytometry. Cytoplasmic calcium (Ca2+) was measured by the Ca2+ binding dyes Fluo-3 AM and flippase activity was assessed by translocation rate of fluorescent phosphatidylserine (PS) analogue NBD-PS. Protein levels of phospho-myosin light chain (MLC, a Rho kinase substrate) and phospho-extracellular signal-regulated kinase 1 or 2 (ERK1/2) were determined by western blotting. The score of actin colocalization was assessed by phalloidin-FITC using an immunofluorescent microscopy. Results: EMPs level markedly increased after bubble stimulus. Cytoplasmic calcium (Ca2+) significantly elevated (P< 0.05), flippase activity decreased (P< 0.05), protein levels of phospho- MLC and phospho- ERK1/2 significantly increased (P< 0.05, P < 0.05), and the score of actin colocalization markedly reduced (P< 0.05) in bubble-stimulated HUVECs. All the above changes except the increase in phospho-ERK1/2 can be reversed by Ca2+ channel blocker LaCl3 (P< 0.05). Additionally, MLC phosphorylation was significantly inhibited and actin colocalization markedly increased by Rho kinase inhibitor pretreatment and more importantly, bubble-induced EMPs markedly decreased. Conclusions: These results demonstrate that bubble stimulates EMPs formation by cytoplasmic Ca2+ elevation and subsequently activating Rho kinase pathway and cytoskeleton reorganization. Simultaneously, cytoplasmic Ca2+ inhibits the flippase activity and subsequently increases phosphatidylserine exposure, which also contributes to EMPs formation.

scholarly journals Synthesis of 1,25-Dihydroxyvitamin D3 by Human Endothelial Cells Is Regulated by Inflammatory Cytokines: A Novel Autocrine Determinant of Vascular Cell Adhesion

2002 ◽  
Vol 13 (3) ◽  
pp. 621-629
Author(s):  
Daniel Zehnder ◽  
Rosemary Bland ◽  
Ravinder S. Chana ◽  
David C. Wheeler ◽  
Alexander J. Howie ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Cell Adhesion ◽  
Inflammatory Cytokines ◽  
Vascular Tissue ◽  
Umbilical Vein ◽  
Primary Cultures ◽  
Human Endothelial Cells ◽  
Functional Studies ◽  
Reverse Transcription Pcr ◽  
Umbilical Vein Endothelial Cells

ABSTRACT. In addition to its calciotropic function, the secosteroid 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) has potent nonclassical effects. In particular, local production of 1,25D3 catalyzed by the enzyme 1α-hydroxylase (1α-OHase) may act as an autocrine/paracrine immunomodulatory mechanism. To investigate the significance of this in vascular tissue the expression and function of 1α-OHase in human endothelial cells was characterized. Immunohistochemical and in situ hybridization analyses show, for the first time, the presence of 1α-OHase mRNA and protein in endothelial cells from human renal arteries as well as postcapillary venules from lymphoid tissue. Reverse transcription–PCR and Western blot analyses confirmed the presence of 1α-OHase in primary cultures of human umbilical vein endothelial cells (HUVEC). Enzyme activity in HUVEC (318 ± 56 fmoles 1,25(OH)2D3/hr/mg protein) increased after treatment with tumor necrosis factor–α (1054 ± 166, P < 0.01), lipopolysaccharide (1381 ± 88, P < 0.01), or forskolin (554 ± 56, P < 0.05). Functional studies showed that exogenously added 1,25(OH)2D3 or its precursor, 25-hydroxyvitamin D3 (25(OH)D3), significantly decreased HUVEC proliferation after 72 h of treatment (33% and 11%, respectively). In addition, after 24 h treatment, both 1,25(OH)2D3 and 25(OH)D3 increased the adhesion of monocytic U937 cells to HUVEC (159% and 153%, respectively). These data indicate that human endothelia are able to produce active vitamin D. The rapid induction of endothelial 1α-OHase activity by inflammatory cytokines suggests a novel autocrine/paracrine role for the enzyme, possibly as a modulator of endothelial cell adhesion.

scholarly journals E-Selectin Mediates Porphyromonas gingivalis Adherence to Human Endothelial Cells

2012 ◽  
Vol 80 (7) ◽  
pp. 2570-2576 ◽  
Author(s):  
Toshinori Komatsu ◽  
Keiji Nagano ◽  
Shinsuke Sugiura ◽  
Makoto Hagiwara ◽  
Naomi Tanigawa ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Porphyromonas Gingivalis ◽  
Umbilical Vein ◽  
Vascular Inflammation ◽  
Periodontal Pathogen ◽  
Sialyl Lewis X ◽  
Necrosis Factor Alpha ◽  
Content Type ◽  
Tnf Α ◽  
Umbilical Vein Endothelial Cells

ABSTRACTPorphyromonas gingivalis, a major periodontal pathogen, may contribute to atherogenesis and other inflammatory cardiovascular diseases. However, little is known about interactions betweenP. gingivalisand endothelial cells. E-selectin is a membrane protein on endothelial cells that initiates recruitment of leukocytes to inflamed tissue, and it may also play a role in pathogen attachment. In the present study, we examined the role of E-selectin inP. gingivalisadherence to endothelial cells. Human umbilical vein endothelial cells (HUVECs) were stimulated with tumor necrosis factor alpha (TNF-α) to induce E-selectin expression. Adherence ofP. gingivalisto HUVECs was measured by fluorescence microscopy. TNF-α increased adherence of wild-typeP. gingivalisto HUVECs. Antibodies to E-selectin and sialyl Lewis X suppressedP. gingivalisadherence to stimulated HUVECs.P. gingivalismutants lacking OmpA-like proteins Pgm6 and -7 had reduced adherence to stimulated HUVECs, but fimbria-deficient mutants were not affected. E-selectin-mediatedP. gingivalisadherence activated endothelial exocytosis. These results suggest that the interaction between host E-selectin and pathogen Pgm6/7 mediatesP. gingivalisadherence to endothelial cells and may trigger vascular inflammation.

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