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Osteoarthritis (OA) is characterized by the infiltration and adhesion of monocyte into the joint synovium. Vascular cell adhesion molecule 1 (VCAM-1) is a critical cell adhesion molecule that controls monocyte motility during OA progression. Cordycerebroside A, a cerebroside compound isolated from Cordyceps militaris, inhibits the production of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in synovial macrophages, but has not yet been investigated in OA. Gene Expression Omnibus (GEO) dataset analysis revealed higher levels of VCAM-1 and CD11b (a monocyte marker) in OA synovial tissue compared with normal healthy tissue. The same results were observed in anterior cruciate ligament transaction (ACLT)-induced OA in rats compared with normal healthy controls. Cordycerebroside A markedly suppressed VCAM-1 expression and monocyte adhesion in human OA synovial fibroblasts. The MEK, ERK and AP-1 signaling cascades regulated cordycerebroside A-induced inhibition of VCAM-1 production. Thus, cordycerebroside A is a promising agent for the treatment of OA.

Atherosclerosis is a chronic inflammatory disease and the underlying cause of most cardiovascular diseases. Interleukin (IL)-1β facilitates early atherogenic lesion formation by increasing monocyte adhesion to endothelial cells via upregulation of adhesion molecules, including intercellular adhesion molecule-1 (ICAM-1). MicroRNAs (miRNAs) have been shown to be associated with inflammatory conditions in the vascular system. The expression of circulating miR-1914–5p is reportedly downregulated in patients with cardiovascular diseases. However, the role of miR-1914–5p downregulation in IL-1β–induced endothelial cell dysfunction and the effect of miR-1914–5p on lesion formation remain unclear. Therefore, we investigated whether miR-1914–5p is associated with monocyte adhesion in human endothelial cells. IL-1β decreased miR-1914–5p expression in EA.hy926 cells. In addition, miR-1914–5p depletion enhanced ICAM-1 expression and monocyte adhesion in EA.hy926 cells. Moreover, miR-1914–5p mimic suppressed monocyte adhesion and ICAM-1 expression induced by IL-1β in endothelial cells. These results suggest that suppression of miR-1914–5p expression by IL-1β may be an important regulator in mediating monocyte adhesion in endothelial cells. Further investigation of miR-1914–5p may lead to the development of novel therapeutic strategies for atherosclerosis.

Erythorbyl laurate (EL) can be produced via lipase-catalyzed esterification between erythorbic acid and lauric acid. In this study, we evaluate the anti-inflammatory effect of EL in the early stage of atherosclerosis. EL suppressed tumor necrosis factor (TNF)-α-induced monocyte adhesion to vascular endothelial cells and expression of vascular cell adhesion molecule (VCAM)-1 in human umbilical vein endothelial cells (HUVECs). Additionally, EL suppressed TNF-α-induced p65/IκB kinase (IKK)/IκB phosphorylation in HUVECs. Western blot analysis of cytosolic and nuclear cell fractions and immunofluorescence showed that EL suppressed TNF-α-induced translocation of p65 from the cytoplasm to the nucleus. EL also inhibited phosphorylation of extracellular-signal-regulated kinase (ERK) 1/2, p38, and c-Jun N-terminal kinases (JNK) 1/2 in HUVECs. EL suppressed TNF-α-induced phosphorylation of Akt, IRAK1, and TAK1 in HUVECs. Quantitative RT-PCR analysis showed that EL significantly suppressed TNF-α-induced interleukin (IL)1B, IL6, TNFA, and CCL2 mRNA expression in HUVECs. Additionally, oral administration of EL suppressed TNF-α-induced IL6 and TNFA expression in the mouse aorta. EL could represent a promising functional nutrient that can be ingested for the prevention of vascular inflammation via decreased monocyte infiltration to the vascular endothelium and suppression of inflammatory nuclear factor (NF)-κB and mitogen-activated protein kinases (MAPKs) signaling pathways.

Monocyte migration is an important process in inflammation and atherogenesis. Identification of the key signalling pathways that regulate monocyte migration can provide prospective targets for prophylactic treatments in inflammatory diseases. Previous research showed that the focal adhesion kinase Pyk2, Src kinase and MAP kinases play an important role in MCP-1-induced monocyte migration. In this study, we demonstrate that MCP-1 induces iPLA 2 activity, which is regulated by PKCβ and affects downstream activation of Rac1 and Pyk2. Rac1 interacts directly with iPLA 2 and Pyk2, and plays a crucial role in MCP-1-mediated monocyte migration by modulating downstream Pyk2 and p38 MAPK activation. Furthermore, Rac1 is necessary for cell spreading and F-actin polymerization during monocyte adhesion to fibronectin. Finally, we provide evidence that Rac1 controls the secretion of inflammatory mediator vimentin from MCP-1-stimulated monocytes. Altogether, this study demonstrates that the PKCβ/iPLA 2 /Rac1/Pyk2/p38 MAPK signalling cascade is essential for MCP-1-induced monocyte adhesion and migration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Vascular inflammation and oxidative stress are the major causes of endothelial dysfunction leading to cardiovascular disease. Previously, we have reported the anti-inflammatory activity of zein hydrolysate and its-derived peptides. However, the underlying mechanisms have not been understood. In this study, we report that zein hydrolysate and its derived peptides can inhibit the tumor necrosis factor-α (TNF-α)-induced expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), the adhesion of U937 cells to EA.hy926 cells and superoxide production in EA.hy926 cells. Zein hydrolysate and its peptides also suppressed TNF-α-induced down-regulation of TNF receptor 1 (TNFR1) and phosphorylation of p65 involved in modulation of the NF-κB pathway. Our study suggests that zein hydrolysate and its derived peptides exhibited anti-inflammatory activity via preventing TNF-α induced monocyte adhesion to endothelial cells and NF-κB activation.

Background: Ulmus davidiana var. japonica Rehder (UD) has long been used in traditional folk medicine in Asia. This study is designed to investigate the antiadhesive activity of the ethanol extract of UD (UDE) and its underlying mechanisms in cultured endothelial cells. Methods: The dried root bark of UD was extracted with 80% (v/v) ethanol. The antiadhesive activity of the UDE was investigated in cultured human umbilical vein endothelial cells and human embryonic kidney epithelial 293T (HEK 293T) cells stably transfected with pGL3-vascular cell adhesion molecule (VCAM)-1-luc. Monocyte adhesion in endothelial cells was induced by tumor necrosis factor-alpha (TNF-α), and the protective effects of UDE on monocyte–endothelial cell adhesion, VCAM-1 expression, reactive oxygen species production, and nuclear factor-κB activity were determined. Results: Exposure to UDE at a concentration of 3–30 μg/mL for 24 hours produced no detectable cytotoxicity in human umbilical vein endothelial cells, but it significantly inhibited TNF-α-induced monocyte adhesion and VCAM-1 expression. TNF-α treatment of HEK 293T/VCAM-1-luc cells resulted in increased luciferase activity of the VCAM-1 promoter, which was inhibited by treatment with UDE. Additionally, TNF-α-induced reactive oxygen species generation, nuclear translocation of nuclear factor-κB, and IκBα degradation in human umbilical vein endothelial cells were effectively reduced by treatment with 30 μg/mL of UDE. Conclusion: Our results indicated that UDE treatment inhibited TNF-α-induced monocyte adhesion in endothelial cells, suggesting that UD may reduce vascular endothelial inflammation.

Calcific aortic valve disease affects the aortic side of the valve, exposed to low magnitude multidirectional ("disturbed) blood flow, more than it affects the ventricular side, exposed to high magnitude uniaxial flow. Overt disease is preceded by endothelial dysfunction and inflammation. Here we investigate the potential role of the transforming growth factor-β (TGF-β) receptor ALK5 in this process. Although ECs are always subject to shear stress due to blood flow, and their responses to shear stress are important in healthy valve development and homeostasis, low magnitude multidirectional flow can induce pathophysiological changes. Previous work has shown ALK5 to be an important mechanosensor. ALK5 transduces mechanically sensed signals via the activation of the SMAD2/3 transcriptional modulators. However, it is currently unclear precisely how ALK5-mediated shear stress responses translate into pathological changes under conditions of chronically disturbed flow. Here, we demonstrate that ALK5 mechanosensory signalling influences flow-induced endothelial leukocyte adhesion and paracellular permeability. Low magnitude multidirectional flow resulted in downregulation of the receptor, accompanied by increased SMAD2 phosphorylation, in human umbilical vein endothelial cell (HUVEC) monolayers. These changes correlated with elevated monocyte adhesion and significantly increased transendothelial transport of an albumin-sized tracer. These effects were abolished by inhibition of ALK5 kinase activity. Analysis of ALK5 expression patterns in porcine aortic valve tissue corroborated the findings from cell-based experiments. Together, these results suggest that ALK5 has a role in shear stress-associated cardiovascular disease pathology, emphasising the importance of further mechanistic investigations and supporting it as a potential therapeutic target., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Oxidized low-density lipoprotein (ox-LDL)-induced endothelial inflammation plays an important role in the development of cardiovascular diseases. G protein-coupled receptors (GPCR) are gaining traction as potential treatment targets due to their roles in mediating a wide range of physiological processes. GPR120 is a recently identified omega-3 fatty acid receptor. We hypothesized that agonism of GPR120 might attenuate ox-LDL-induced endothelial dysfunction. In the present study, we tested the effects of two GPR120 agonists-GW9508 and TUG-891-in mitigating endothelial insult induced by ox-LDL in human aortic endothelial cells (HAECs). Real-time PCR, western blot, and ELISA analyses were used in our experiments. Our findings demonstrate that GPR120 is downregulated by exposure to ox-LDL, suggesting a role for GPR120 in mediating ox-LDL insult. Furthermore, we found that agonism of GPR120 could suppress oxidative stress and inflammation by inhibiting the production of reactive oxygen species and the expression of proinflammatory cytokines. Importantly, we show that agonism of GPR120 prevents the attachment of monocytes to endothelial cells by suppressing the expression of VCAM-1 and E-selectin. Finally, we show that agonism of GPR120 exerts a remarkable atheroprotective effect by elevating the expression level of Krüppel-like factor 2 (KLF2). Together, our results demonstrate a potential role for specific agonism of GPR120 in the prevention of endothelial damages induced by ox-LDL., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Pulmonary endothelial injury is central in the pathogenesis of acute lung injury (ALI). The MAPK signaling cascades are generally thought to be involved in the molecular mechanism underlying the ALI development, but their roles in pulmonary endothelial injury is poorly understood. We thus examined the involvement of the MAPK family member in inflammatory responses of human pulmonary microvascular endothelial cells (HPMVECs) stimulated with LPS and IFN-γ. HPMVECs were found to exhibit the upregulation of expression of Toll-like receptor 4 by IFN-γ, resulting in potentiation of inflammatory cytokine release by LPS stimulation. All MAPKs, ERK1/2, JNK, and p38, were activated by simultaneous stimulation with LPS/IFN-γ. JNK activation in cells stimulated with LPS/IFN-γ was significantly potentiated by the two different p38 inhibitors, SB203580 and RWJ67657, suggesting the negative regulation of JNK activation by p38 in HPMVECs. The mRNA and protein expression levels of ICAM-1 were eliminated by the JNK inhibitor, suggesting that ICAM-1 expression is positively regulated by JNK. The p38 inhibitor significantly enhanced ICAM-1 expression. ERK1/2 activation was not responsible for the LPS/IFN-γ-induced ICAM-1 upregulation in HPMVECs. THP-1 monocyte adhesion to HPMVECs under LPS/IFN-γ stimulation was inhibited by the JNK inhibitor and enhanced by the p38 inhibitor. We conclude that, in HPMVECs stimulated with LPS/IFN-γ, JNK mediates ICAM-1 expression that can facilitate leukocyte adherence and transmigration, while p38 MAPK negatively regulates the upregulation of ICAM-1 through inhibition of JNK activation., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Vascular inflammation has been suggested to play a key role in the initiation and progression of atherosclerosis. Hyperoside (HPS) is a plant-derived quercetin 3-d-galactoside reported to have anti-inflammatory, anti-oxidant, anti-cancer, anti-hyperglycemic, anti-coagulant, and cardioprotective activities. However, the effects of HPS on vascular inflammation have not been studied. Therefore, in this study, we investigated the suppressive effect of HPS on tumor necrosis factor-α (TNFα)-dependent inflammatory responses in MOVAS-1 cells, a murine vascular smooth muscle cell (VSMC) line. HPS did not show any significant cytotoxicity up to 10 μg/mL over 24 h. TNFα challenge of VSMCs significantly increased the mRNA (3-fold) and protein expression (20-fold) of vascular cell adhesion molecule-1 (VCAM-1). However, these increases were abolished in the presence of HPS. Additionally, HPS significantly decreased monocyte adhesion to TNFα-stimulated VSMCs in a dose-dependent manner. Further, TNFα challenge induced activation of mitogen-activated protein kinases (MAPKs), such as p38 MAPK (38.0 ± 3.08 fold), JNK (51.6 ± 2.26 fold), and ERK (14.1 ± 0.77 fold); expression of nuclear factor-κB (NF-κB; ≅ 4-fold) and TNF receptor 1 (TNFR1; 2.7 ± 0.198 fold) were also increased. Notably, the TNFα-induced expression of these molecules was also significantly inhibited by the presence of HPS. Given that p38 MAPK, JNK, ERK, NF-κB, and TNFR1 all play regulatory roles in the expression of VCAM-1, this study provides insight into the mechanism of action of HPS. In summary, HPS can inhibit TNFα-mediated vascular inflammatory responses and has potential as a new anti-atherosclerotic drug., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Puerarin has properties of anti-oxidation and anti-inflammation, which has been demonstrated protective effects in atherosclerosis and other cardiovascular diseases. However, the detail molecular mechanism still remains unclear. Here, we determined whether the atheroprotective effect of puerarin was by reducing monocyte adhesion and explored the underlying mechanism. The results showed that puerarin dose- and time-dependently reduced oxLDL-induced monocyte THP-1 adhesion to HUVECs and the expression of adhesion-related genes such as VCAM-1, ICAM-1, MCP-1 and IL-8 in HUVECs. Puerarin activated ERK5 phosphorylation and up-regulated expressions of downstream KLF2 and its targeted genes endothelial nitric oxide synthase and thrombomodulin. However, the protective effects were reversed by ERK5/KLF2 pathway inhibitor XDM8-92, BIX02189 or KLF2 siRNA suggesting the pathway involved in the function. The ex vivo assay, in which THP-1 adhesion to endothelium isolated from apoE-/- mice received various treatments further confirmed the results from HUVECs. Finally, we found that the atherosclerotic lesions in both cross sections at aortic root and whole aorta were significantly reduced in high fat-diet (HFD) mice with puerarin treatment compared with the HFD-only mice, but were increased respectively by 76% and 71% in XMD8-92 group, and 82% and 73% in BIX02189 group. Altogether, the data revealed that puerarin inhibited the monocyte adhesion in vitro and in vivo and thus reduced atherosclerotic lesions in apoE-/- mice; the protective effects were mediated by activation of ERK5/KLF2 signaling pathway. Our findings advance the understanding of puerarin function in atherosclerosis and point out a way to prevent the disease., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Mesenchymal stem/stromal cells derived from chorionic villi of human term placentae (pMSCs) produce a unique combination of molecules, which modulate important cellular functions of their target cells while concurrently suppressing their immune responses. These properties make MSCs advantageous candidates for cell-based therapy. Our first aim was to examine the effect of high levels of oxidative stress on pMSC functions. pMSCs were exposed to hydrogen peroxide (H 2 O 2 ) and their ability to proliferate and adhere to an endothelial cell monolayer was determined. Oxidatively stressed pMSCs maintained their proliferation and adhesion potentials. The second aim was to measure the ability of pMSCs to prevent oxidative stress-related damage to endothelial cells. Endothelial cells were exposed to H 2 O 2 , then co-cultured with pMSCs, and the effect on endothelial cell adhesion, proliferation and migration was determined. pMSCs were able to reverse the damaging effects of oxidative stress on the proliferation and migration but not on the adhesion of endothelial cells. These data indicate that pMSCs are not only inherently resistant to oxidative stress, but also protect endothelial cell functions from oxidative stress-associated damage. Therefore, pMSCs could be used as a therapeutic tool in inflammatory diseases by reducing the effects of oxidative stress on endothelial cells., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Ulmus davidiana var. japonica Rehder (UD) has long been used in traditional folk medicine in Asia. This study is designed to investigate the antiadhesive activity of the ethanol extract of UD (UDE) and its underlying mechanisms in cultured endothelial cells., Methods: The dried root bark of UD was extracted with 80% (v/v) ethanol. The antiadhesive activity of the UDE was investigated in cultured human umbilical vein endothelial cells and human embryonic kidney epithelial 293T (HEK 293T) cells stably transfected with pGL3-vascular cell adhesion molecule (VCAM)-1-luc. Monocyte adhesion in endothelial cells was induced by tumor necrosis factor-alpha (TNF-α), and the protective effects of UDE on monocyte-endothelial cell adhesion, VCAM-1 expression, reactive oxygen species production, and nuclear factor-κB activity were determined., Results: Exposure to UDE at a concentration of 3-30 μg/mL for 24 hours produced no detectable cytotoxicity in human umbilical vein endothelial cells, but it significantly inhibited TNF-α-induced monocyte adhesion and VCAM-1 expression. TNF-α treatment of HEK 293T/ VCAM-1-luc cells resulted in increased luciferase activity of the VCAM-1 promoter, which was inhibited by treatment with UDE. Additionally, TNF-α-induced reactive oxygen species generation, nuclear translocation of nuclear factor-κB, and IκBα degradation in human umbilical vein endothelial cells were effectively reduced by treatment with 30 μg/mL of UDE., Conclusion: Our results indicated that UDE treatment inhibited TNF-α-induced monocyte adhesion in endothelial cells, suggesting that UD may reduce vascular endothelial inflammation.

An increasing number of evidence suggests a protective role of dietary anthocyanins against cardiovascular diseases. Anthocyanins' extensive metabolism indicates that their metabolites could be responsible for the protective effects associated with consumption of anthocyanin-rich foods. The aim of this work was to investigate the effect of plasma anthocyanins and their metabolites on the adhesion of monocytes to TNFα-activated endothelial cells and on the expression of genes encoding cell adhesion molecules. Human umbilical vein endothelial cells (HUVECs) were exposed to circulating anthocyanins: cyanidin-3-arabinoside, cyanidin-3-galactoside, cyanidin-3-glucoside, delphinidin-3-glucoside, peonidin-3-glucoside, anthocyanin degradation product: 4-hydroxybenzaldehyde, or to their gut metabolites: protocatechuic, vanillic, ferulic and hippuric acid, at physiologically-relevant concentrations (0.1-2 μM) and time of exposure. Both anthocyanins and gut metabolites decreased the adhesion of monocytes to HUVECs, with a magnitude ranging from 18.1% to 47%. The mixture of anthocyanins and that of gut metabolites also reduced monocyte adhesion. However, no significant effect on the expression of genes encoding E-selectin, ICAM1 and VCAM1 was observed, suggesting that other molecular targets are involved in the observed effect. In conclusion, this study showed the potency of anthocyanins and their gut metabolites to modulate the adhesion of monocytes to endothelial cells, the initial step in atherosclerosis development, under physiologically-relevant conditions., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Cigarette smoking is an important risk factor for chronic obstructive pulmonary disease (COPD), yet its pathogenic mechanisms are not yet fully understood. Endothelial dysfunction is known to be involved in the pathogenesis of COPD. A detailed understanding of the mechanism involved in its progression would have a substantial impact on the optimization and development of treatment strategies. Here, we report that the expression of SIRT4, a mitochondrial sirtuin, is markedly down-regulated in cigarette smoke extract (CSE)-treated human pulmonary microvascular endothelial cells (HPMECs). Overexpression of SIRT4 significantly inhibits CSE-induced mononuclear cell adhesion to HPMECs. Consistently, we found that overexpression of SIRT4 attenuates the induction of vascular cell adhesion molecule 1 (VCAM-1) and E-selectin. Importantly, SIRT4 was found to negatively regulate CSE-induced NF-κB activation via inhibiting the degradation of IκBα. Moreover, we also found that proinflammatory cytokines interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and IL-6, the downstream target genes of NF-κB, are also inhibited by overexpression of SIRT4. These results suggest that SIRT4 protects HPMECs exposed to CSE stress via a mechanism that may involve the NF-κB pathway. Strategies based on the enhancement of SIRT4 may prove to be beneficial in the treatment of cigarette smoking caused COPD., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Objective: In whole genome and single gene analyses, genetic variation at the vascular cell adhesion molecule-1 (VCAM-1) locus has been associated with inflammatory disease and stroke in sickle cell anaemia. In the current work, we investigated the functional impact of VCAM-1 missense variants and their effect on cell-cell adhesion., Methods and Results: To determine the functional in vitro relevance of five missense VCAM-1 variants (S318F; T384A; G413A; L555V; I716L), we generated wild type and single variant VCAM-1 forms [318F, 384A, 413A, 555V, 716L] in EA.hy926 endothelial cells. Real-time PCR, western blot and ELISA analyses revealed significant differences in mRNA and protein levels for VCAM-1 variants. Monocytic cell lines THP-1 and U937 showed significantly increased adhesion to endothelial cells overexpressing VCAM-1 forms 318F, 555V and 716L compared to those overexpressing wild type VCAM-1 (p < 0.05)., Conclusions: VCAM-1-dependent cell adhesion to endothelial cells in vitro is significantly increased when expressing VCAM-1 missense mutations 318F, 555V and 716L. The underlying mechanism involves altered VCAM-1 protein levels and function. This observation may be of particular relevance for chronic inflammatory pathophysiologic conditions involving cell-cell adhesion such as atherosclerosis and other proinflammatory conditions., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)