• Molecules and Cells
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• v.38 no.1
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• pp.14-19
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• 2015

Eph receptors and their ligands, ephrins, represent the largest group of the receptor tyrosine kinase (RTK) family, and they mediate numerous developmental processes in a variety of organisms. Ephrins are membrane-bound proteins that are mainly divided into two classes: A class ephrins, which are linked to the membrane by a glycosylphosphatidylinositol (GPI) linkage, and B class ephrins, which are transmembrane ligands. Based on their domain structures and affinities for ligand binding, the Eph receptors are also divided into two groups. Trans-dimerization of Eph receptors with their membrane-tethered ligands regulates cell-cell interactions and initiates bidirectional signaling pathways. These pathways are intimately involved in regulating cytoskeleton dynamics, cell migration, and alterations in cellular dynamics and shapes. The EphBs and ephrinBs are specifically localized and modified to promote higher-order clustering and initiate of bidirectional signaling. In this review, we present an in-depth overview of the structure, mechanisms, cell signaling, and functions of EphB/ephrinB in cell adhesion and migration.

• Journal of Periodontal and Implant Science
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• v.29 no.2
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• pp.333-350
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• 1999

The modulation of leukocyte cell surface adhesion molecules may influence the development of cellular events that determine the course of the inflammatory process. Direct interaction between activated T cells and monocytes resulted in a large production of $IL-1{\beta}$ by monocytes. In this reactions, adhesion molecules play an important part, yet the role of them in Tmonocytes interaction remain unclear. This study was undertaken in an effort to elucidate, 1) the influence of 1.25(OH)$_2D_3-induced$ differentiation on the monocyte responsiveness to direct contact with T lymphocytes, and 2) the role of adhesion molecules on the T-monocyte direct interaction. Initially, I observed that direct contact of monocyte cell line THP-1 with stimulated fixed T cell line HuT78 markedly induces IL-1${\beta}$ production by THP-1. $IL-1{\beta}$ production was higher when THP-1 had been previously exposed to 1.25(OH)$_2D_3$ as compared to control, with ${\alpha}$- 1.25(OH)$_2D_3$ dose-dependent and exposure time-dependent manner. It was shown that 1.25(OH)$_2D_3$ also increased the expression of ${\beta}_2$ integrin adhesion receptor Mac-1(CD11b/CD18) dose- and timedependently, but did not increase the expression of human leukocyte antigen- D(HLA-D) and intercellular adhesion molecule-1(ICAM-1). The $IL-1{\beta}$ producing activity of THP-1 cells correlated well with the ability to induce the Mac-1 expression on THP-1 surface. Monoclonal antibody raised against relevant cell surface glycoproteins on THP-1 were tested for their ability to block the response of THP-1 to T cells. Antibody to Mac-1 only partially blocked $IL-1{\beta}$ production by THP-1, whereas antibodies to ICAM-1 and HLA-D did not. These data indicate that regulation of Mac-1 expression on THP-1 cells can alter the responsiveness of these cells to contact by activated T cells, however other unknown structures on the THP-1 cells may be involved in this process also.

• Herbal Formula Science
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• v.20 no.1
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• pp.1-11
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• 2012

Objectives : This experimental study was designed to investigate the inhibitory effects of combination with Korean red ginseng and Gastrodia rhizoma on vascular dysfunction in high-fat/cholesterol diet-induced hyperlipidemia. Methods : Sprague-Dawley rats were fed with 7.5% cocoa butter and 1.25% cholesterol for 10 weeks, with Panax ginseng (PG), and mixtures of Panax ginseng and Gastrodia rhizoma (PGM), respectively. Results : Chronic treatment with PG and PGM significantly decreased body weight. The aortic expression of cell adhesion molecules such as intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin were markedly increased in hyperlipidemia rats. Interestingly, PGM significantly decreased cell adhesion molecules expression. However, there was no significant decrease in PG group. In addition, PG and PGM group inhibited high-fat/cholesterol diet-induced cytokine such as monocyte chemoattractant protein (MCP-1) mRNA expression. Furthermore, PG and PGM group significantly decreased c-reactive protein protein (CRP) level. Especially, PGM significantly accentuated the decrease of MCP-1 mRNA expression and CRP level. Conclusions : the present study provides an evidence that combination with Panax ginseng and Gastrodia rhizoma enhances anti-vascular protective effects through suppression of vascular inflammation in hyperlipidemic rats.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.2
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• pp.109-115
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• 2005

Endothelial activation and subsequent recruitment of inflammatory cells are important steps in atherogenesis. The increased levels of cell adhesion molecules (CAM) have been identified in diabetic vasculatures, but the underlying mechanisms remain unclear. To determine the relationship among vascular production of superoxide, expression of CAM and diabetes, superoxide generation and expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E- and P-selectin in the aorta from control (C57BL/6J) and diabetic mice (ob/ob) were measured. In situ staining for superoxide using dihydroethidium showed an increased superoxide production in diabetic aorta, accompanied with an enhanced NAD(P)H oxidase activity. Immunohistochemical analysis revealed that the endothelial expression of ICAM-1 ($3.5{\pm}0.4$) and VCAM-1 ($3.8{\pm}0.3$) in diabetic aorta was significantly higher than those in control aorta ($0.9{\pm}0.5$ and $1.6{\pm}0.3$, respectively), accompanied with the enhanced expression of gp91phox, a membrane subunit of NAD(P)H oixdase. Furthermore, there was a strong positive correlation (r=0.89, P＜0.01 in ICAM-1 and r=0.88, P＜0.01 in VCAM-1) between ICAM-1/VCAM-1 expression and vascular production of superoxide. The present data indicate that the increased production of superoxide via NAD(P)H oxidase may explain the enhanced expression of CAM in diabetic vasculatures.

• Nutritional Sciences
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• v.8 no.3
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• pp.153-158
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• 2005

Numerous natural herbal compounds have been reported to inhibit adhesion and migration of leukocytes to the site of inflammation Licorice extracts, which have been widely used in traditional Chinese medicinal preparation, possess various pharmacological effects. Isoliquiritigenin, a biogenetic precursor of flavonoids with various pharmacological effects, is a natural pigment present in licorice. We attempted to explore whether licorice extracts and isoliquiritigenin mitigate monocyte adhesion to tumor necrosis factor-$\alpha$ (TNF-$\alpha$)-activated human umbilical vein endothelial cells (HUVEC). In addition, it was tested whether the inhibition of monocyte adhesion to the activated HUVEC accompanied a reduction in vascular cell adhesion molecule-l expression(VCAM-l). Dry-roasted licorice extracts in methylene chloride but not in ethanol markedly interfered with THP-l monocyte adhesion to INF-$\alpha$-activated endothelial cells. licochalcone A compound isolated from licorice extract in methylene chloride appeared to modestly inhibit the interaction of THP-l monocytes and activated endothelium. In addition, isoliquiritigenin abolished the monocyte adhesion with attenuating VCAM-l protein expression on HUVEC induced by INF-$\alpha$. These results demonstrated that non-polar components from dry-roasted licorice extracts containing licochalcone A as well as isoliquiritigenin were active in blocking monocyte adhesion to cytokine-activated endothelimn, which appeared to be mediated most likely through the inhibition of VCAM-l expression on HUVEC. Therefore, licorice may hamper initial inflammatory events on the vascular endothelium involving induction of endothelial cell adhesion molecules.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.3
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• pp.157-162
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• 2011

Vascular inflammation process has been suggested to be an important risk factor in the development of atherosclerosis. Recently we reported that induction of peroxisome proliferator-activated receptor-${\gamma}$ (PPAR-${\gamma}$) selectively inhibits vascular cell adhesion molecule-1 (VCAM-1) but not intercellular cell adhesion molecule-1 (ICAM-1) in tumor necrosis factor (TNF)-${\alpha}$-activated human umbilical vein endothelial cells (HUVEC). In this study, we investigated whether genipin inhibits expression of cellular adhesion molecules, which is relevant to inflammation. Pretreatment with genipin reduced reactive oxygen species (ROS) production and expression of VCAM-1, but not ICAM-1 in TNF-${\alpha}$-activated HUVEC. Genipin dose- and time-dependently increased PPAR-${\gamma}$ expression and inhibited TNF-${\alpha}$-induced phosphorylation of Akt and PKC with different degrees. Finally, genipin prevented TNF-${\alpha}$-induced adhesion of U937 monocytic cells to HUVEC. Taken together, these results indicate that upregualtion of PPAR-${\gamma}$ by genipin selectively inhibits TNF-${\alpha}$-induced expression of VCAM-1, in which regulation of Akt and/or PKC play a key role. We concluded that genipin can be used for the treatment of cardiovascular disorders such as atherosclerosis.

• Archives of Pharmacal Research
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• v.26 no.3
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• pp.244-251
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• 2003

Plant nutrients are believed to provide protection against various diseases including inflammation. Since interactions of the cell adhesion molecules are known to play important roles in mediating inflammation, inhibiting adhesion protein upregulation is a possible therapeutic target. In this study, the interacellular adhesion molecule-1 (ICAM-1) was induced in human umbilical endothelial cells (HUVECs) after stimulation with $TNF-{\alpha}$. In addition, alginate, ascorbic acid and allicin were demonstrated to inhibit the $TNF-{\alpha}$ induced expression of ICAM-1 on the HUVECs in a dose-dependent manner. These compounds also inhibited the production of NO and $H_2O_2$ induced by $TNF-{\alpha}$, which suggests that the inhibition of ICAM-1 expression by the three compounds may be due to the modulated production of the reactive oxygen/nitrogen components. Overall, these results indicate that these dietary components have a therapeutic potential in the treatment of various inflammatory disorders associated with an increase in endothelial leukocyte adhesion molecules.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2004.11a
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• pp.362-366
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• 2004

Quantitative evaluation of substrates for cells is essential to understanding cell-material adhesive interaction and it is also necessary for the development of new biomaterials. Many cells on adhesive molecules will form an organization of actin into bundles and production of the large, highly organized structures termed focal adhesions. To better understand adhesion formations between cells and substrata, we have quantified the force required to displace attached cell. we allowed rabbit knee chondrocyte to attach on a substratum of microscope slide glass. Our results demonstrate that a force is required to detach cells is changed according to detachment time variation.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.3
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• pp.156-162
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• 2006

The halophilic enterobacteria, Enterobacteria cancerogenus, was isolated from the intestines of the fusiform fish (Trachurus japonicus) to yield a protein-like material termed PLM-f74. PLM-f74 was characterized by strong inhibition ratios to angiogenesis (82.8% at the concentration of $18.5{\mu}g/mL$) and elevated antioxidative capacities with low toxicity. The PLM-f74 is a glycoprotein comprised of saccharides and amino acids. PLM-f74 inhibited non-activated U937 monocytic cell adhesion to HUVECs activated with IL-$1{\beta}$ by 78.0%, and the adherence of U937 cells treated with the PLM-f74 and stimulated with IL-$1{\beta}$ to unstimulated HUVECs decreased by 102%. When both cell types were pretreated with PLM-f74, the adhesion of U937 cells to IL-$1{\beta}$ stimulated HUVECs was completely suppressed by 121% at a concentration of 18.5 ug/mL. PLM-f74 blocked signal pathways from VEGFR2, PI3K, ${\beta}$-catenin and VE-cadherin to NF-kB based on western bolt analysis. And also inhibited IL-1-stimulated HUVEC expression of the adhesion molecules, ICAM-1 by 40%, VCAM-1 by 60%, and E-selectin by 70% at the same concentration noted above. New anti-angiogenic and anti-cell adhesion materials showing elevated antioxidative capacities and non-toxicity may be expected from these results.

• Molecules and Cells
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• v.21 no.2
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• pp.224-228
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• 2006

Glypican-3 (GPC3) is a member of the glypican family, which encodes cell-surface heparan-sulfate proteoglycans, and is frequently upregulated in hepatocellular carcinoma (HCC). We have recently reported that blocking endogenous GPC3 expression promotes the growth of HCC cell lines, suggesting that GPC3 plays a negative role in HCC cell proliferation. Here, we report that forced expression of GPC3 reduced the growth of HCC cells. We also found that FGF2-mediated cell proliferation was inhibited by GPC3. In addition, we observed that the adhesion of HCC cells to collagen type I and fibronectin was decreased by GPC3, whereas cellular migration and invasiveness were stimulated. Collectively, these results suggest that progression of hepatocellular carcinoma is associated with upregulation of GPC3.