Vascular Cell Adhesion Molecule-1 Promoter Research Articles

Effect of macrophages on the expression of vascular cell adhesion molecule 1 in ovarian carcinoma cells and its mechanism

Objective To explore the effect of macrophages on the expression of vascular cell adhesion molecule 1 (VCAM1) in ovarian carcinoma cells and its mechanism. Methods Phorbol ester and lipopolysaccharide were used to activate the monocyte THP-1 that would become macrophages . Enzyme linked immunosorbent assay (ELISA) was used to detect the cytokines level in the supernatant of macrophages. The effect of macrophages' supernatant on VCAM1 mRNA expression of ovarian HEY and IGROV1 carcinoma cells was detected by using quantitative real-time and polymerase chain reaction (qRT-PCR). Western blot was used to detect the effect of macrophages' supernatant on VCAM1 protein expression of ovarian carcinoma cells with VCAM1 over expression (HEY-VCAM1 and IGROV1-VCAM1). Dual-luciferase report gene assay was used to detect the effect of macrophages' supernatant and the cytokines on promoter transcriptional activity in different truncations of human embryonic kidney cells HEK293T VCAM1 gene. Results Compared with the supernatant of THP-1 cells, the release number of tumor necrosis factor α (TNF-α), interleukin (IL)-6 and IL-12 in supernatant from macrophages was increased (all P < 0.05), and IL-10 was decreased (t=3.841, P=0.019). The levels of VCAM1 mRNA in HEY and IGROV1 cells were upregulated by macrophages' supernatant and 1 ng/ml TNF-α, and macrophages' supernatant could promote the expression levels of VCAM1 protein in HEY-VCAM1 cells and IGROV1-VCAM1 cells. Compared with the empty vector (pGV354) control group [(8.6±0.2)×10-3 relative light unit (RLU)], the reporter gene luciferase activity of human embryonic kidney cells HEK293T VCAM1 gene promoter region were upregulated by supernatant from macrophages located at -1 641 bp to +12 bp including the transcription binding site of AP-1 [(109.4±3.4)×10-3 RLU], and there was a significant difference (t=29.42, P < 0.001). Compared with the negative control group untreated by cytokine [(21.0±0.5)×10-3 RLU], 100 ng/ml TNF-α could promote the transcriptional activity of -1641 bp to +12 bp promoter of VCAM1 in HEK293T cells [(23.4±0.4)×10-3 RLU; t=4.134, P=0.001]. 150 ng/ml IL-6 had no effect on the transcriptional activity of the promoter [(21.4±1.0)×10-3 RLU; t=0.328, P=0.708]. 5 ng/ml IL-12 inhibited the transcriptional activity of the promoter [(14.3±1.0)×10-3 RLU; t=6.390, P < 0.001]. Conclusion Macrophages can promote VCAM1 expression in ovarian carcinoma cells by secreting inflammatory factors like TNF-α to affect VCAM1 promoter region containing AP1 transcription binding site and can promote VCAM1 mRNA expression in ovarian cancer cells. Key words: Ovarian neoplasms; Macrophages; Cytokines; Vascular cell adhesion molecule 1

Resveratrol Attenuates Staphylococcus Aureus-Induced Monocyte Adhesion through Downregulating PDGFR/AP-1 Activation in Human Lung Epithelial Cells.

Staphylococcus aureus (S. aureus) is a very common Gram-positive bacterium. It is widely distributed in air, soil, and water. S. aureus often causes septicemia and pneumonia in patients. In addition, it is considered to play a key role in mediating cell adhesion molecules upregulation. Resveratrol is a natural antioxidant with diverse biological effects, including the modulation of immune function, anti-inflammation, and cancer chemoprevention. In this study, we proved that S. aureus-upregulated vascular cell adhesion molecule-1 (VCAM-1) expression in human lung epithelial cells (HPAEpiCs) was inhibited by resveratrol. We also observed that resveratrol downregulated S. aureus-enhanced leukocyte count in bronchoalveolar lavage (BAL) fluid in mice. In HPAEpiCs, S. aureus stimulated c-Src, PDGFR, p38 MAPK, or JNK1/2 phosphorylation, which was inhibited by resveratrol. S. aureus induced the adhesion of THP-1 cells (a human monocytic cell line) to HPAEpiCs, which was also reduced by resveratrol. Finally, we found that S. aureus induced c-Src/PDGFR/p38 MAPK and JNK1/2-dependent c-Jun and ATF2 activation and in vivo binding of c-Jun and ATF2 to the VCAM-1 promoter, which were inhibited by resveratrol. Thus, resveratrol functions as a suppressor of S. aureus-induced inflammatory signaling, not only by inhibiting VCAM-1 expression but also by diminishing c-Src, PDGFR, JNK1/2, p38 MAPK, and AP-1 activation in HPAEpiCs.

Histone H3 Serine 10 Phosphorylation Facilitates Endothelial Activation in Diabetic Kidney Disease

Post-translational modification of histone proteins epigenetically affects gene transcription. The histone modifications that have been most extensively linked to the development of diabetes complications are histone (de)methylation and (de)acetylation, whereas other modifications have been comparatively overlooked. Here, by examining the means by which podocytes may influence the glomerular endothelial phenotype, we identified a role for the phosphorylation of histone H3 on serine residue 10 (H3Ser10) in mediating endothelial activation in diabetes. Culture media conditioned by high glucose-exposed podocytes induced glomerular endothelial vascular cell adhesion molecule-1 (VCAM-1) upregulation and was enriched for the chemokine CCL2 in a JAK2-dependent manner. Antagonism of CCR2, the cognate receptor for CCL2, decreased the endothelial VCAM-1 upregulation that was induced either by conditioned medium or by recombinant CCL2, whereas CCR2 knockout mice exhibited diminished glomerular VCAM-1 upregulation when challenged by diabetes. Recombinant CCL2 induced glomerular endothelial VCAM-1 upregulation through a pathway mediated by p38 MAPK, its nuclear substrates MSK1/2 and subsequent H3Ser10 phosphorylation, which was enriched at the VCAM-1 promoter. H3Ser10 phosphorylation levels were elevated in the kidneys of streptozotocin-diabetic endothelial nitric oxide synthase knockout (STZ-eNOS-/-) mice and in the glomeruli of humans with diabetic kidney disease. Finally, treatment of STZ-eNOS-/- mice with an inhibitor of JAK2 decreased both urinary CCL2 excretion and renal H3Ser10 phosphorylation. Collectively, these findings indicate that histone phosphorylation promotes endothelial activation in diabetes. Histone protein phosphorylation should be set alongside other more canonical histone modifications when considering chromatin modifications that influence diabetic kidney disease and that may be amenable to therapeutic intervention. Disclosure T. Alghamdi: None. S. Batchu: None. M.J. Hadden: None. Y. Liu: None. B. Bowskill: None. L. Geldenhuys: None. F.S. Siddiqi: Research Support; Self; AstraZeneca. S. Majumder: None. A. Advani: Research Support; Self; AstraZeneca, Boehringer Ingelheim GmbH. Other Relationship; Self; Boehringer Ingelheim GmbH.

EphA2 stimulates VCAM-1 expression through calcium-dependent NFAT1 activity

Endothelial cell activation by proinflammatory stimuli drives leukocyte recruitment through enhanced expression of counter-receptors such as vascular cell adhesion molecule-1 (VCAM-1). We previously demonstrated that activation of the receptor tyrosine kinase EphA2 with its ligand ephrin-A1 induces VCAM-1 expression. Here, we sought to characterize the proinflammatory signaling pathways involved. Analysis of over-represented transcription factors in ephrin-A1-induced genes identified multiple potential transcriptional regulators, including the Rel family members nuclear factor-κB (NF-κB/p65) and nuclear factor of activated T-cells (NFAT). While ephrin-A1 failed to induce endothelial NF-κB activation, NF-κB inhibitors prevented ephrin-A1-induced VCAM-1 expression, suggesting basal NF-κB activity is required. In contrast, ephrin-A1 induced a robust EphA2-dependent increase in NFAT activation, and mutation of the NF-κB/NFAT-binding sites in the VCAM-1 promoter blunted ephrin-A1-induced promoter activity. NFAT activation classically occurs through calcium-dependent calcineurin activation, and inhibiting NFAT signaling with calcineurin inhibitors (cyclosporine A, FK506) or direct NFAT inhibitors (A-285222) was sufficient to block ephrin-A1-induced VCAM-1 expression. Consistent with robust NFAT activation, ephrin-A1-induced an EphA2-dependent calcium influx in endothelial cells that was required for ephrin—A1-induced NFAT activation and VCAM-1 expression. This work provides the first data showing EphA2-dependent calcium influx and NFAT activation and identifies NFAT as a novel EphA2-dependent proinflammatory pathway in endothelial activation.

RGC-32 (Response Gene to Complement 32) Deficiency Protects Endothelial Cells From Inflammation and Attenuates Atherosclerosis.

The objective of this study is to determine the role and underlying mechanisms of RGC-32 (response gene to complement 32 protein) in atherogenesis. RGC-32 was mainly expressed in endothelial cells of atherosclerotic lesions in both ApoE-/- (apolipoprotein E deficient) mice and human patients. Rgc-32 deficiency (Rgc32-/-) attenuated the high-fat diet-induced and spontaneously developed atherosclerotic lesions in ApoE-/- mice without affecting serum cholesterol concentration. Rgc32-/- seemed to decrease the macrophage content without altering collagen and smooth muscle contents or lesional macrophage proliferation in the lesions. Transplantation of WT (wild type) mouse bone marrow to lethally irradiated Rgc32-/- mice did not alter Rgc32-/--caused reduction of lesion formation and macrophage accumulation, suggesting that RGC-32 in resident vascular cells, but not the macrophages, plays a critical role in the atherogenesis. Of importance, Rgc32-/- decreased the expression of ICAM-1 (intercellular adhesion molecule-1) and VCAM-1 (vascular cell adhesion molecule-1) in endothelial cells both in vivo and in vitro, resulting in a decrease in TNF-α (tumor necrosis factor-α)-induced monocyte-endothelial cell interaction. Mechanistically, RGC-32 mediated the ICAM-1 and VCAM-1 expression, at least partially, through NF (nuclear factor)-κB signaling pathway. RGC-32 directly interacted with NF-κB and facilitated its nuclear translocation and enhanced TNF-α-induced NF-κB binding to ICAM-1 and VCAM-1 promoters. RGC-32 mediates atherogenesis by facilitating monocyte-endothelial cell interaction via the induction of endothelial ICAM-1 and VCAM-1 expression, at least partially, through NF-κB signaling pathway.

Abstract 211: Response Gene to Complement 32 Deficiency Protects Endothelial Cell From Inflammation and Attenuates Atheroslcerosis

Response gene to complement 32 (RGC-32) is involved in diet-induced obesity and hepatic steatosis. Therefore, we hypothesized that RGC-32 plays a role in atherosclerosis. Our current study showed that RGC-32 expression was dramatically induced in endothelial cells (ECs) of the atherosclerotic lesions from both apolipoprotein E-deficient (ApoE -/- ) mice and diseased human arteries. RGC-32 deficiency (Rgc32 -/- ) significantly attenuated the high-fat diet-induced and spontaneously developed atherogenesis in ApoE -/- mice without affecting the serum lipid profiles. In addition, Rgc32 -/- decreased the macrophage content without affecting fibrous cap size. Rgc32 -/- in bone marrow cells had no effect on atherosclerosis development, and Rgc32 -/- mice transplanted with wild-type (WT) bone marrow cells exhibited decreased atherosclerotic lesion area and macrophage infiltration, suggesting that RGC-32 in resident vascular cells plays a critical role in the atherogenesis. Rgc32 -/- decreased the expression of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in ECs both in vivo and in vitro , resulting in a decreased monocyte-EC interaction. Mechanistically, RGC-32 regulated ICAM-1 and VCAM-1 transcription via activation of nuclear factor (NF)-κB. It appeared that RGC-32 interacted with NF-κB, which facilitated NF-κB binding to ICAM-1 and VCAM-1 promoters. Indeed, blockade of NF-κB activity by its selective inhibitor ammonium pyrrolidinedithiocarbamate blocked RGC-32-induced ICAM-1 and VCAM-1 expression. In conclusion, RGC-32 promoted atherogenesis by inducing monocyte-EC interaction through NF-κB-dependent induction of endothelial ICAM-1 and VCAM-1 expression.

Magnolol Nanoparticles Exhibit Improved Water Solubility and Suppress TNF-α-Induced VCAM-1 Expression in Endothelial Cells

The expression of the adhesion molecule vascular cell adhesion molecule-1 (VCAM-1) on endothelial cells enables the attachment of leukocytes to the endothelium, which may lead to inflammation and the development of atherosclerosis. Magnolol is a major bioactive compound derived from the plant species Magnolia officinalis. In this study, we synthesized a novel nanoparticle formulation of magnolol to improve its water solubility and physicochemical properties, evaluated its effects on TNF-α-induced VCAM-1 expression in endothelial cells, and determined the signal transduction pathways involved. Our findings demonstrated that the magnolol nanoparticle system showed great improvements in physicochemical properties and water solubility owing to a reduction in particle size, transformation from a crystalline to amorphous structure, and the formation of hydrogen bonds with the nanoparticle carriers. In terms of its biological actions, magnolol nanoparticles attenuated TNF-α-induced VCAM-1 protein expression, promoter activity, and mRNA expression in endothelial cells in vitro. This was found to be mediated by the ERK, AKT, and NF-κB signaling pathways. In addition, magnolol nanoparticles inhibited TNF-α-induced leukocyte adhesion to endothelial cells, and suppressed TNF-α-induced VCAM-1 expression in the aortic endothelium of mice. In summary, since magnolol nanoparticles inhibit endothelial VCAM-1 expression and leukocyte adhesion to endothelial cells, this novel drug formulation may be a potentially useful therapeutic formulation to prevent the development of atherosclerosis and inflammatory diseases.

A novel endothelial-derived anti-inflammatory activity significantly inhibits spontaneous choroidal neovascularisation in a mouse model.

BackgroundEndothelial cells (EC) grown on collagen particles inhibit intimal hyperplasia in animal models when applied perivascularly, and this effect appears to be, at least in part, the result of EC-derived soluble factors that suppress local vascular inflammation. To elucidate the molecular basis of the therapeutic effects of EC grown on collagen particles, the anti-inflammatory activity of conditioned medium from these cells was characterized.MethodsHuman aortic EC (HAEC) and, for chromatin immunoprecipitation assays, human umbilical vein EC (HUVEC) were treated with tumor necrosis factor alpha (TNFα) in the presence of conditioned medium generated by HAEC grown on collagen particles (ECPCM), and the anti-inflammatory effects were evaluated by analysing the expression of the inflammation-related adhesion molecules E-selectin and vascular cell adhesion molecule-1 (VCAM-1). The therapeutic activity of ECPCM was studied using the mouse strain JR5558, which develops spontaneous choroidal neovascularisation (CNV) lesions driven by local inflammation.ResultsECPCM significantly suppressed TNFα-induced expression of E-selectin and VCAM-1. ECPCM did not affect the mRNA stability of the two genes, but suppressed TNFα-induced binding of the p65 subunit of NF-kB transcription factor to E-selectin and VCAM-1 promoters. In vivo, systemic ECPCM treatment significantly reduced the CNV area and the recruitment of activated macrophages to the lesions. Characterization of the molecule responsible for the anti-inflammatory activity in ECPCM indicates that it is unlikely to be a protein and that it is not any of the better characterized EC-derived anti-inflammatory molecules.ConclusionsMedium conditioned by HAEC grown on collagen particles exhibits significant anti-inflammatory activity via inhibition of genes that mediate inflammatory responses in EC.Electronic supplementary materialThe online version of this article (doi:10.1186/s13221-016-0036-4) contains supplementary material, which is available to authorized users.

Salusin-β induces foam cell formation and monocyte adhesion in human vascular smooth muscle cells via miR155/NOX2/NFκB pathway.

Vascular smooth muscle cells (VSMCs) are indispensible components in foam cell formation. Salusin-β is a stimulator in the progression of atherosclerosis. Here, we showed that salusin-β increased foam cell formation evidenced by accumulation of lipid droplets and intracellular cholesterol content, and promoted monocyte adhesion in human VSMCs. Salusin-β increased the expressions and activity of acyl coenzyme A:cholesterol acyltransferase-1 (ACAT-1) and vascular cell adhesion molecule-1 (VCAM-1) in VSMCs. Silencing of ACAT-1 abolished the salusin-β-induced lipid accumulation, and silencing of VCAM-1 prevented the salusin-β-induced monocyte adhesion in VSMCs. Salusin-β caused p65-NFκB nuclear translocation and increased p65 occupancy at the ACAT-1 and VCAM-1 promoter. Inhibition of NFκB with Bay 11-7082 prevented the salusin-β-induced ACAT-1 and VCAM-1 upregulation, foam cell formation and monocyte adhesion in VSMCs. Scavenging ROS, inhibiting NADPH oxidase or knockdown of NOX2 abolished the effects of salusin-β on ACAT-1 and VCAM-1 expressions, p65-NFκB nuclear translocation, lipid accumulation and monocyte adhesion in VSMCs. Salusin-β increased miR155 expression, and knockdown of miR155 prevented the effects of salusin-β on ACAT-1 and VCAM-1 expressions, p65-NFκB nuclear translocation, lipid accumulation, monocyte adhesion and ROS production in VSMCs. These results indicate that salusin-β induces foam formation and monocyte adhesion via miR155/NOX2/NFκB-mediated ACAT-1 and VCAM-1 expressions in VSMCs.

PDE4 inhibition reduces neointima formation and inhibits VCAM-1 expression and histone methylation in an Epac-dependent manner

Phosphodiesterase 4 (PDE4) activity mediates cAMP-dependent smooth muscle cell (SMC) activation following vascular injury. In this study we have investigated the effects of specific PDE4 inhibition with roflumilast on SMC proliferation and inflammatory activation in vitro and neointima formation following guide wire-induced injury of the femoral artery in mice in vivo. In vitro, roflumilast did not affect SMC proliferation, but diminished TNF-α induced expression of the vascular cell adhesion molecule 1 (VCAM-1). Specific activation of the cAMP effector Epac, but not PKA activation mimicked the effects of roflumilast on VCAM-1 expression. Consistently, the reduction of VCAM-1 expression was rescued following inhibition of Epac. TNF-α induced NFκB p65 translocation and VCAM-1 promoter activity were not altered by roflumilast in SMCs. However, roflumilast treatment and Epac activation repressed the induction of the activating epigenetic histone mark H3K4me2 at the VCAM-1 promoter, while PKA activation showed no effect. Furthermore, HDAC inhibition blocked the inhibitory effect of roflumilast on VCAM-1 expression. Both, roflumilast and Epac activation reduced monocyte adhesion to SMCs in vitro. Finally, roflumilast treatment attenuated femoral artery intima-media ratio by more than 50% after 4weeks. In summary, PDE4 inhibition regulates VCAM-1 through a novel Epac-dependent mechanism, which involves regulatory epigenetic components and reduces neointima formation following vascular injury. PDE4 inhibition and Epac activation might represent novel approaches for the treatment of vascular diseases, including atherosclerosis and in-stent restenosis.

The saponin DT-13 attenuates tumor necrosis factor-α-induced vascular inflammation associated with Src/NF-кB/MAPK pathway modulation.

This study aimed to explore the effect of DT-13 (25(R,S)-ruscogenin- 1-O- [β-d-glucopyranosyl- (1→2)][β-d-xylopyranosyl-(1→3)]-β -d- fucopyranoside) on tumor necrosis factor (TNF)-α-induced vascular inflammation and the potential molecular mechanisms. In vitro, DT-13 suppressed TNF-α-induced adhesion and migration of human umbilical vein endothelial cells (HUVECs) by inhibiting the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). DT-13 markedly suppressed NF-кB p65 phosphorylation, and when NF-кB p65 was over-expressed, the inhibitory effect of DT-13 on adhesion molecular decreased. DT-13 also suppressed TNF-α induced luciferase activities of ICAM-1 and VCAM-1 promoter containing NF-κB binding sites. Furthermore, DT-13 markedly suppressed p38 phosphorylation and Src degradation induced by TNF-α, whereas had no significant effect on ERK and JNK activation. In vivo, DT-13 at 4 mg/kg prevented vascular inflammation and the expression of adhesion molecules induced by TNF-α in mice. These findings suggest that DT-13 abrogates vascular inflammation by down-regulating adhesion molecules associated with modulating the NF-кB, p38MAPK, Src signaling pathways, and NF-κB binding site is at least one of the targets of DT-13. This study provides novel information regarding the mechanism by which DT-13 exerts its effects on vascular inflammation, which is important for the onset and progression of various diseases.

Abstract 547: PDE4 Inhibition Protects Against Neointimal Hyperplasia and Diminishes VCAM-1 Expression and Histone Methylation Through an Epac-Dependent Pathway

Introduction: Upregulation of phosphodiesterase 4 (PDE4) activity causes cAMP-dependent vascular smooth muscle cell (VSMC) activation at sites of vascular inflammation and tissue remodeling. Hypothesis: PDE4 inhibition reduces VSMC activation and neointima formation following vascular injury. Methods: C57BL/6 mice (n=16) treated with roflumilast underwent guide wire-induced endothelial denudation injury of the femoral artery. Neointima formation was quantified after 4 weeks. In vitro, we analyzed the effects of roflumilast on VSMC proliferation and inflammation. Results: Roflumilast treatment attenuated neointima formation by 40% (17252 ± 2315 vs. 10119 ± 738 μm 2 , p=0,02) and femoral artery intima-media ratio by more than 50% (2,76 ± 0,32 vs. 1,35 ± 0,25 ,p=0,005). In vitro, roflumilast did not affect VSMC proliferation, but diminished TNF-α induced expression of the inflammatory marker vascular cell adhesion molecule 1 (VCAM-1) by 60% (p&lt;0.05). Specific activation of the cAMP effector Epac, but not PKA activation mimicked the effects of roflumilast on VCAM-1 expression. Consistently, the reduction of VCAM-1 expression was rescued in the presence of the Epac inhibitor ESI-09 and following siRNA mediated knockdown of Epac1. TNF-α induced NFκB p65 translocation and VCAM-1 promotor activity were not altered by roflumilast in VSMCs. However, Roflumilast treatment and Epac activation repressed the induction of the activating epigenetic histone mark H3K4me2 at the VCAM-1 promoter, while PKA activation showed no effect. In accordance with the reduction of VCAM-1 in vitro, roflumilast treated mice displayed decreased expression of VCAM-1 and the macrophage markers F4/80 and CD68 during neointima formation. Consistently, immunohistochemical analysis of the vessel wall showed reduced Mac2 staining, indicating decreased macrophage accumulation after vascular injury. Conclusions: PDE4 inhibtion reduces neointimal hyperplasia after vascular injury and regulates VCAM-1 through a novel Epac-dependent mechanism, which modulates specific histone methylation patterns. PDE4 inhibition might represent a novel approach for the treatment of vascular diseases, including atherosclerosis and in-stent restenosis.

PINK1 and Its Familial Parkinson's Disease-Associated Mutation Regulate Brain Vascular Endothelial Inflammation

Parkinson's disease (PD) is a debilitating disorder that affects movement. Inflammation-mediated endothelial dysfunction has been found to be involved in neurodegenerative diseases, including PD. More than 40 PTEN-induced putative kinase 1 (PINK1) mutations have been found in PD patients. The effects of PINK1 in vascular inflammation are as yet unknown. In this study, our findings revealed that PINK1 can be increased by the inflammatory cytokine tumor necrosis factor-α in primary human brain microvascular endothelial cells (HBMECs). We found that wild-type PINK1 prevents expression of the adhesion molecule vascular cell adhesion molecule-1 (VCAM-1), thus inhibiting the attachment of monocytes to brain endothelial cells. However, PINK1G309D, the loss-of-function mutation associated with early-onset familial PD, promotes expression of VCAM-1 and exacerbates attachment of monocytes to brain endothelial cells. Mechanism studies revealed that overexpression of wild-type PINK1 inhibits the VCAM-1 promoter by inhibiting the transcriptional activity of interferon regulatory factor 1 (IRF-1). However, PINK1G309D promotes the VCAM-1 promoter by increasing the transcriptional activity of IRF-1.

Disruption of asymmetric dimethylarginine-induced RelA/P65 association with actin in endothelial cells

Asymmetric dimethylarginine (ADMA) activates nuclear factor (NF)-κB in endothelial cells, while actin-stabilizing or -destabilizing drugs prevent ADMA-induced activation of NF-κB. Here we investigated how actin-targeting drugs regulated ADMA-induced NF-κB activation in endothelial cells. Human umbilical vein endothelial cells were treated with ADMA for 24 h in the absence and presence of cytochalasin D or jasplakinolide. Expression levels of proteins and genes were measured by immunoblotting and reverse-transcription polymerase chain reaction, respectively. Chromatin immunoprecipitation was used to detect the binding of NF-κB to the vascular cell adhesion molecule 1 (VCAM-1) promoter. The association of actin with RelA/P65 was detected by immunoprecipitation. It was demonstrated that ADMA induced IκBα degradation, increased nuclear RelA/P65 translocation, and promoted the binding of NF-κB to the VCAM-1 promoter. Consequently, this increased the expression of VCAM-1. In parallel studies, actin-stabilizing and -destabilizing drugs decreased ADMA-induced RelA/P65 nuclear translocation, interfered with NF-κB binding to the VCAM-1 promoter and prevented the expression of VCAM-1. This was independent of total RelA/P65 levels and ADMA-induced IκBα degradation. Most importantly, the association of RelA/P65 with actin was increased after stimulation with ADMA, and impaired after treatment with actin-targeting drugs. In brief, actin-stabilizing or -destabilizing drugs interfere with the ADMA-induced association of RelA/P65 with actin, and consequently disrupt NF-κB activation.

The CCL2/CCR2 Axis Enhances Vascular Cell Adhesion Molecule-1 Expression in Human Synovial Fibroblasts

BackgroundChemokine ligand 2 (CCL2), also known as monocyte chemoattractant protein-1 (MCP-1), belongs to the CC chemokine family that is associated with the disease status and outcomes of osteoarthritis (OA). Here, we investigated the intracellular signaling pathways involved in CCL2-induced vascular cell adhesion molecule-1 (VCAM-1) expression in human OA synovial fibroblasts (OASFs).Methodology/Principal FindingsStimulation of OASFs with CCL2 induced VCAM-1 expression. CCL2-mediated VCAM-1 expression was attenuated by CCR2 inhibitor (RS102895), PKCδ inhibitor (rottlerin), p38MAPK inhibitor (SB203580), and AP-1 inhibitors (curcumin and tanshinone IIA). Stimulation of cells with CCL2 increased PKCδ and p38MAPK activation. Treatment of OASFs with CCL2 also increased the c-Jun phosphorylation and c-Jun binding to the AP-1 element on the VCAM-1 promoter. Moreover, CCL2-mediated CCR2, PKCδ, p38MAPK, and AP-1 pathway promoted the adhesion of monocytes to the OASFs monolayer.Conclusions/SignificanceOur results suggest that CCL2 increases VCAM-1 expression in human OASFs via the CCR2, PKCδ, p38MAPK, c-Jun, and AP-1 signaling pathway. The CCL2-induced VCAM-1 expression promoted monocytes adhesion to human OASFs.

IL-35 Suppresses Lipopolysaccharide-Induced Endothelial Cell Activation Through Downregulation of MAPK Signaling-Mediated Upregulation of Adhesion Molecule VCAM-1

Abstract 3310Our previous reports showed that survival/apoptosis of CD4+CD25+Foxp3+ regulatory T cells (Tregs) modulates vascular inflammation even though the mode of Tregs inhibition was unknown. Interleukin-35 (IL-35), consisting of two subunits Epstein-Barr virus–induced gene 3 (EBI3) and p35, is a novel anti-inflammatory cytokine, which is a member of the interleukin-12 (IL-12) cytokine family. IL-35 is produced by Tregs. It has been shown that IL-35 suppresses chronic inflammatory diseases such as asthma and inflammatory bowel diseases. However, an important question of whether IL-35 can carry out Tregs suppression and inhibit endothelial cell (EC) activation in acute inflammation remained unknown. Here we found that IL-35 significantly inhibits lung neutrophil infiltration into the surrounding areas of bronchioles and alveolar space when induced by intraperitoneal injection of lipopolysaccharide (LPS) in wild type mice and EBI3-deficient mice. Furthermore, cremaster microvasculature study using intravital microscopy showed IL-35 significantly suppresses leukocyte adhesion to the vascular wall as well, suggesting IL-35 inhibition of endothelial activation. Mechanistically, IL-35 inhibited LPS-induced upregulation of adhesion molecules on human aortic endothelial cells, a marker of endothelial activation, including vascular cell adhesion molecule 1 (VCAM-1). IL-35 acted through new IL-35 dimeric receptors gp130 and IL-12Rβ2, and inhibited VCAM-1 promoter transcription in mitogen-activated protein kinase (MAPK)-mediated pathway. These results provide a novel insight on Tregs and IL-35 inhibition of vascular inflammation. Disclosures:No relevant conflicts of interest to declare.

Tanshinone IIA inhibits TNF-α-mediated induction of VCAM-1 but not ICAM-1 through the regulation of GATA-6 and IRF-1

The goal of this study was to investigate the differential effect of tanshinone IIA on the induction of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) by TNF-α and the possible molecular mechanisms by which it regulates ICAM-1 and VCAM-1 expression differentially. Stimulation of human umbilical vein endothelial cells (HUVEC) with TNF-α increased ICAM-1 and VCAM-1 expressions, and the pretreatment with tanshinone IIA concentration dependently inhibited VCAM-1 expression but not ICAM-1 expression. In previous study, PI3K/Akt, PKC and Jak/STAT-3 pathways were involved in the TNF-α-mediated induction of VCAM-1 but not ICAM-1. Thus, we examined the effect of tanshinone IIA on TNF-α-mediated activations of PI3K/Akt, PKC and Jak/STAT-3 pathways. Tanshinone IIA efficiently inhibited the phosphorylations of Akt, PKC and STAT-3 by TNF-α. Moreover, we determined the effect of tanshinone IIA on IRF-1 or GATAs induction and binding activity to VCAM-1 promoter since the upstream promoter region of VCAM-1 but not ICAM-1 contains IRF-1 and GATA binding motifs. Western blot analysis and ChIP assay showed that tanshinone IIA efficiently inhibited TNF-α-increased nuclear level of IRF-1 and GATA-6 and their binding affinity to VCAM-1 promoter region. Taken together, tanshinone IIA selectively inhibits TNF-α-mediated expression of VCAM-1 but not ICAM-1 through modulation of PI3/Akt, PKC and Jak/STAT-3 pathway as well as IRF-1 and GATA-6 binding activity.

Loss of Id3 Increases VCAM-1 Expression, Macrophage Accumulation, and Atherogenesis in Ldlr –/– Mice

Inhibitor of differention-3 (Id3) promotes B cells homing to the aorta and atheroprotection in Apoe(-/-) mice. We sought to determine the impact of loss of Id3 in the Ldlr((-/-)) mouse model of diet-induced atherosclerosis and identify novel Id3 targets in the vessel wall. Ex vivo optical imaging confirmed that Id3((-/-)) Ldlr((-/-)) mice have significantly fewer aortic B cells than Id3((+/+)) Ldlr(-/-) mice. After 8 and 16 weeks of Western diet, Id3((-/-)) Ldlr((-/-)) mice developed significantly more atherosclerosis than Id3((+/+)) Ldlr((-/-)) mice, with Id3(+/-) Ldlr(-/-) mice demonstrating an intermediate phenotype. There were no differences in serum lipid levels between genotypes. Immunostaining demonstrated that aortas from Id3((-/-)) Ldlr((-/-)) mice had greater intimal macrophage density and C-C chemokine ligand 20 and vascular cell adhesion molecule 1 (VCAM-1) expression compared with Id3((+/+)) Ldlr(-/-) mice. Real-time polymerase chain reaction demonstrated increased VCAM-1 mRNA levels in the aortas of Id3(-/-) Ldlr(-/-) mice. Primary vascular smooth muscle cells from Id3((-/-)) mice expressed greater amounts of VCAM-1 protein compared with control. Gain and loss of function studies in primary vascular smooth muscle cells identified a role for Id3 in repressing VCAM-1 promoter activation. Chromatin immunoprecipitation demonstrated interaction of E12 with the VCAM-1 promoter, which is inhibited by Id3. Id3 is an atheroprotective transcription regulator with targets in both B cells and vessel wall cells leading to reduced macrophage accumulation and reduced atherosclerosis formation.

Sulforaphane inhibits restenosis by suppressing inflammation and the proliferation of vascular smooth muscle cells

ObjectiveSulforaphane, a naturally occurring organosulfur compound in broccoli, has chemopreventive properties in cancer. However, the effects of sulforaphane in vascular diseases have not been examined. We therefore aimed to investigate the effects of sulforaphane on vascular smooth muscle cell (VSMC) proliferation and neointimal formation and the related mechanisms. MethodsThe expression of vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1) was examined in VSMCs. The nuclear translocation of nuclear factor-κB (NF-κB) and GATA6 expression was examined in VSMCs and in a carotid artery injury model by Western blot and immunohistochemistry. We also investigated whether local delivery of sulforaphane affected neointimal formation. ResultsSulforaphane inhibited the mRNA and protein expression of VCAM-1 induced by tumor necrosis factor (TNF)-α in VSMCs. Treatment of VSMCs with sulforaphane blocked TNF-α-induced IκBα degradation and NF-κB p65 and GATA6 expression. Furthermore, NF-κB p65 and GATA6 expression were reduced in sulforaphane-treated carotid injury sections. Notably, binding of GATA6 to the VCAM-1 promoter was dramatically reduced by sulforaphane. The MTT, BrdU incorporation, and in vitro scratch assays revealed that the proliferation and migration of VSMCs were reduced by sulforaphane. Furthermore, local administration of sulforaphane significantly reduced neointima formation 14 days after vascular injury in rats. ConclusionsOur results indicate that sulforaphane inhibits neointima formation via targeting of adhesion molecules through the suppression of NF-κB/GATA6. Furthermore, sulforaphane regulates migration and proliferation in VSMCs. Sulforaphane may be a potential therapeutic agent for preventing restenosis after vascular injury.

DNA‐DEPENDENT PROTEIN KINASE IS CRITICAL FOR VCAM‐1 EXPRESSION UPON TNF TREATMENT THROUGH PHOSPHORYLATION OF p50 NF‐kappa B: A CRITICAL INVOLVEMENT IN VASCULAR AND LUNG INFLAMMATION

NF‐κB is critical for vascular cell adhesion molecule 1 (VCAM‐1) expression during vascular inflammation. We show that DNA‐dependent protein kinase (DNA‐PK) is required for VCAM‐1 expression in response to TNF‐α in an established cell line and in primary endothelial cells. DNA‐PK deficiency, achieved by DNA‐PKcs heterozygosity, reduced VCAM‐1 expression in the aorta in an animal model of septic shock and blocked airway neutrophilia in an animal model of acute lung injury. Interestingly, such effect unravels a novel function for DNA‐PK independent of its role in immune competence. Phosphorylation and nuclear translocation of p65 NF‐κB (p65) was insufficient for VCAM‐1 expression in response to TNF‐α. The requirement for p50 NF‐κB (p50) was associated with its interaction with and phosphorylation by DNA‐PK, which appears to be dominant over the requirement for p65 activation. Additionally, DNA‐PK activity appeared to increase the κB‐site binding ability of p50/p50 and p50/p65 dimers to VCAM‐1 promoter. Serine 20 in p50 was found to be phosphorylated by DNA‐PK. Re‐establishing wild‐type p50, but not its S20/A mutant, in p50‐knockout cells reversed VCAM‐1 expression. Together, these results elucidate a novel mechanism for the regulation of VCAM‐1 expression by DNA‐PK through phosphorylation of p50 and its critical involvement in vascular and lung inflammation.