• Nutrition Research and Practice
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• v.1 no.4
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• pp.285-290
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• 2007

The leukocyte recruitment and transmigration across the endothelial barrier into the vessel wall are crucial steps in atherosclerosis. Leukocyte trafficking on the endothelium is elicited by induction of endothelial adhesion molecules, and its transmigration is mediated by degradation of basement membrane proteins through enzymatic activity of matrix metalloproteinases (MMP). The current study investigated whether resveratrol, a polyphenol present in grapes and red wine, was capable of inhibiting leukocyte adhesion to tumor necrosis factor (TNF)-${\alpha}$-activated endothelium. It was found that resveratrol inhibited the TNF-${\alpha}$-activated endothelial expression of vascular cell adhesion molecule-1 in a dose-dependent manner. In addition, resveratrol hampered THP-1 monocyte adhesion to activated endothelial cells. This study further examined whether resveratrol interfered with transendothelial migration of leukocytes. The MMP-2 gelatinolytic activity of endothelial cells was enhanced by TNF-${\alpha}$, which was attenuated by an addition of ${\geq}25{\mu}M$ resveratrol. In addition, 25 ${\mu}M$ resveratrol mitigated the MMP-9 activity of THP-1 cells, followed by a marked inhibition of transendothelial migration. These results demonstrated that resveratrol suppressed monocyte adhesion and migration induced by TNF-${\alpha}$ through modulating expression of adhesion molecules and gelatinolytic activity of MMP. These findings suggest that dietary resveratrol may be therapeutic agent for inhibiting leukocyte recruitment into the subendothelium during inflammatory atherosclerosis.

• Tuberculosis and Respiratory Diseases
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• v.51 no.3
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• pp.211-223
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• 2001

Background : Rhinovirus infection of the airways results in increased permeability of the airway vascular endothelium with the influx of plasma proteins, including lipids such as LDL. In vitro studies on the effect of oxLDL on leukocytes has shown many pro inflammatory effects on multiple leukocytes. We hypothesized that oxLDL is one mechanism for recruiting granulocytes to the airways during a RV infection. Therefore, chemotaxis and transendothelial migration, in response to nLDL, was determined for these granulocytes. Methods : nLDL was oxidized with 5mM Cu2S04 for 20-24 hours. 3-5 105 cells were loaded into the Transwell filter while the chemotatic agonists were placed in the lower well for chemotaxis. Confluent monolayers on HPMEC were grown on Transwell filters for transendothelial migration. The filters were washed and eosinophils and neutrophils loaded on to the filter with the chemotatic agonist was were placed in the lower well. The wells were incubated for 3 hours. The number of migrating cells was counted on a hemocytometer. Results : OxLDL, but not nLDL, is chemotatic for eosinophils and neutrophils. The level of granulocytes chemotaxis was dependent on both the concentration of LDL and its degree of oxidation. OxLDL stimulates eosinophil and neutrophils migration across HPMEC monolayers (+/-IL-$1{\beta}$ preactivation) in a dose dependent manner. Conclusion : Increased vascular permeability during a RV infection may lead to the influx and oxidation of LDL. The resulting oxLDL. is one possible mechanism for the recruitment of neutrophils and eosinophils to the airway interstitial matrix. Once in the airways, granulocytes can further interact with oxLDL to promote airway inflammation.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.382.3-382.3
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• 2002

Atherosclerosis is a progressive disease characterized by the accumulation of lipids and fibrous elements in the arteries. Monocytes/macrophages are involved in many aspects of the development of atheroscleotic plaques. It is known that the intercellular adhesion molecule-1 (ICAM-1) expressed preferentially on endothelial cells of atheroscleotic plaque. promotes local adhesion and transendothelial migration of monocytes, neutrophils. and lymphocytes. Using the human promyelocytic leukemia HL-60 cell line, we investigated the inhibitory effects of methoanol extracts of 175 plants on ICAM-1/LFA-1 mediated cell adhesion. Eight kinds of methanol extracts of tested plants inhibited PMA-induced homotypic aggregated cell adhesion. Eight kinds of methanol extracts of tested plants inhibited PMA-induced homotypic aggregation of HL-60 cells without cytotoxicity at the concentration of 6.25 ${\mu}$g/ml. $CHCl_3$ extracts (1.0 ${\mu}$g/ml) of Saururus chinensis and Chloranthus japonicus significantly inhibited agregation of HL-60 cells without cytoxicity.

• Molecules and Cells
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• v.40 no.5
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• pp.355-362
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• 2017

The ${\beta}2$ integrins are cell surface transmembrane proteins regulating leukocyte functions, such as adhesion and migration. Two members of ${\beta}2$ integrin, ${\alpha}M{\beta}2$ and ${\alpha}X{\beta}2$, share the leukocyte distribution profile and integrin ${\alpha}X{\beta}2$ is involved in antigen presentation in dendritic cells and transendothelial migration of monocytes and macrophages to atherosclerotic lesions. ${\underline{R}}eceptor$ for ${\underline{a}}dvanced$ ${\underline{g}}lycation$ ${\underline{e}}nd$ ${\underline{p}}roducts$ (RAGE), a member of cell adhesion molecules, plays an important role in chronic inflammation and atherosclerosis. Although RAGE and ${\alpha}X{\beta}2$ play an important role in inflammatory response and the pathogenesis of atherosclerosis, the nature of their interaction and structure involved in the binding remain poorly defined. In this study, using I-domain as a ligand binding motif of ${\alpha}X{\beta}2$, we characterize the binding nature and the interacting moieties of ${\alpha}X$ I-domain and RAGE. Their binding requires divalent cations ($Mg^{2+}$ and $Mn^{2+}$) and shows an affinity on the sub-micro molar level: the dissociation constant of ${\alpha}X$ I-domains binding to RAGE being $0.49{\mu}M$. Furthermore, the ${\alpha}X$ I-domains recognize the V-domain, but not the C1 and C2-domains of RAGE. The acidic amino acid substitutions on the ligand binding site of ${\alpha}X$ I-domain significantly reduce the I-domain binding activity to soluble RAGE and the alanine substitutions of basic amino acids on the flat surface of the V-domain prevent the V-domain binding to ${\alpha}X$ I-domain. In conclusion, the main mechanism of ${\alpha}X$ I-domain binding to RAGE is a charge interaction, in which the acidic moieties of ${\alpha}X$ I-domains, including E244, and D249, recognize the basic residues on the RAGE V-domain encompassing K39, K43, K44, R104, and K107.

• Biomolecules & Therapeutics
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• v.18 no.2
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• pp.135-144
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• 2010

The pro-oxidative and pro-inflammatory pathways in vascular endothelium have been implicated in the initiation and progression of atherosclerosis. In fact, inflammatory responses in vascular endothelium are primarily regulated through oxidative stress-mediated signaling pathways leading to overexpression of pro-inflammatory mediators. Enhanced expression of cytokines, chemokines and adhesion molecules in endothelial cells and their close interactions facilitate recruiting and adhering blood leukocytes to vessel wall, and subsequently stimulate transendothelial migration, which are thought to be critical early pathologic events in atherogenesis. Although interleukin-4 (IL-4) was traditionally considered as an anti-inflammatory cytokine, recent in vitro and in vivo studies have provided robust evidence that IL-4 exerts pro-inflammatory effects on vascular endothelium and may play a critical role in the development of atherosclerosis. The cellular and molecular mechanisms responsible for IL-4-induced atherosclerosis, however, remain largely unknown. The present review focuses on the distinct sources of IL-4-mediated reactive oxygen species (ROS) generation as well as the pivotal role of ROS in IL-4-induced vascular inflammation. These studies will provide novel insights into a clear delineation of the oxidative mechanisms of IL-4-mediated stimulation of vascular inflammation and subsequent development of atherosclerosis. It will also contribute to novel therapeutic approaches for atherosclerosis specifically targeted against pro-oxidative and pro-inflammatory pathways in vascular endothelium.

• Korean Chemical Engineering Research
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• v.47 no.4
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• pp.501-505
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• 2009

In this study, we evaluated the effect of soluble EPCR(Soluble Endothelial Protein C Receptor, sEPCR) on the anti-inflammatory activities by activated protein C(APC) in endothelium. We demonstrated that sEPCR inhibited the barrier protective activity, the inhibition of neutrophils adhesion toward endothelial cells and the inhibition of transendothelial migration by APC in endothelial cells. Interestingly, sEPCR also blocked the mechanism by which APC inhibited the expression of cell adhesion molecules(CAM) by TNF-alpha in endothelial cells. These results suggested that the anti-inflammatory activities of APC was inhibited by sEPCR which blocked the binding motifs of Gla domain of APC to membrane bound EPCR. This finding will provide the important evidence in the development of new medicine for the treatment of severe sepsis and inflammatory diseases and good clue for understanding unknown mechanisms by which APC showed the anti-inflammatory activities in endothelium.

• Korean Journal of Pharmacognosy
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• v.33 no.4 s.131
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• pp.343-351
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• 2002

Atherosclerosis is a progressive disease characterized by the accumulation of lipids and fibrous elements in the arteries. Monocyter/macrophages are involved in many aspects of the development of atherosclerotic plaques. It is known that the intercellular adhesion molecule-1(ICAM-1) expressed preferentially on endothelial cells of atherosclerotic plaque, promotes local adhesion and transendothelial migration of monocytes, neutrophils, and lymphocytes. Using the human promyelocytic leukemia HL-60 cell line, we investigated the inhibitory effects of methanol extracts of 175 natural plants on ICAM-1/LFA-1 mediated cell adhesion. Eight kinds of methanol extracts of tested plants inhibited PMA-induces homotypic aggregationof HL-60 cells without cytotoxicity at the concentration of $6.25\;{\mu}g/ml$. They were divided two fractions of $CHCI_3$ and $H_2O$ to use solvent partition. Among them, $CHCI_3$ extract $(1.0\;{\mu}g/ml)$ of Saururus chinensis and Chloranthus japonicus singificantly inhibited aggregation of HL-60 cells without cytotoxicity, respectively.

• Korean Journal of Bronchoesophagology
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• v.5 no.2
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• pp.174-181
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• 1999

The palatine tonsils(tonsils) and pharyngeal tonsils(adenoids) are situated at the entrance of the respiratory and alimentary tracts and represent the first site of contact with a variety of microorganisms and other antigens present in food and inhaled air. They are known as lymphoid organs carrying out the function of cellular and humoral immunity, and so they form a local protective barrier. And the expression of the vascular endothelial adhesion molecules is known to play an important role for the inflammatory reaction in tonsils and adenoids as well as in other inflammatory tissues, by binding with the receptors on the surface of leukocytes. But although several scientific hypotheses on the role of these lympoid tissues have been suggested, their complete functions have remained unknown. The purpose of this study is to present an basic data of the knowledge on the immunologic physiology of the tonsils and adenoids and their role as active immunologic organs that reinforce the mucosal immunity of the entire upper aerodigestive tract. We examined 16 human tonsils and adenoids and the expression of three endothelial adhesion molecules, vascular endothelial adhesion molecule-1(VCAM-1), intracellular adhesion molecule-1(ICAM-1), and E-selection, in tissue sections using immunohistochemistry. We used the inferior turbinate mucosa obtained from 9 patients getting septal surgery as a control group. The expressions of vascular endothelial adhesion molecule-1(VCAM-1) and intracellular adhesion molecule-1 (ICAM-1) were significantly higher in the tonsils and adenoids. But respectively, there were no significant differences between the tonsils and adenoids. The expression of E-selection was significant higher in the tonsils, but not in the adenoids. We observed that tonsils and adenoids showed significantly higher expressions of vascular endothelial adhesion molecule-1(VCAM-1), intracellular adhesion molecule-1(ICAM-1), and E-selection (in the case of E-selection, only in the tonsils). We propose that these adhesion molecules play an important role for the immunologic reaction by the transendothelial migration of lymphocytes and binding with the receptors on the surface of leukocytes.

• The Journal of Korean Society of Virology
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• v.26 no.1
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• pp.47-58
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• 1996

Histopathological vascular changes in hemorrhagic fever with renal syndrome (HFRS) caused by Hantaan virus include increased vascular permeability, disseminated intravascular coagulation, thrombocytopenia and changes in coagulation activity. Although vascular endothelial cells of main target organs such as kidney infected with Hantaan virus are not damaged but swelling of endothelial cells, perivascular exudates and infiltration of mononuclear cells and fresh interstitial hemorrhages are common. However, the pathogenesis of cell infiltration and hemorrhages around vascular endothelial cells are not well understood. Some endothelial cell molecules or vascular adhesins that acts as adhesion moleulces for leukocyte are expressed on endothelial cells close to site of inflammation. However, whether the expression of endothelial adhesion molecules such as vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule (ICAM-1) and endothelial leukocyte adhesion molecule (ELAM) on vascular endothelial cells are increased by infection with Hantaan virus has not been studied. In this study, the relationship between the expression of VCAM-1, ICAM-1 and ELAM and adhesion of mononuclear cells on endothelial cells of human blood vessels infected with Hantaan virus was investigated. The endothelial cells of umbilical vein was passaged three times in culture medium and the monolayered cells were infected with $10^5\;pfu/ml$ of Hantaan virus grown in Vera E6 cell cultures. The multiplication of virus in cultured endothelial cells was monitored by immunohistochemistry and the expression of adhesion molecules was demonstrated by immunohistochemistry using monoclonal antibodies against VCAM-1, ICAM-1 and ELAM. And in situ hybriditation against ICAM-1 was also performed. The endothelial adhesion molecules, VCAM and ICAM, were expressed after 6 hours postinfection, respectively, and their expressions lasted for 72 hours. Similar expression of VCAM and ICAM appeared on endothelial cells by infection with virus, but the expression of ELAM was not recognized up to 72 hours postinfection. Microscopically, it was noted that many monocuclear cells adhered on endothelial cells infected with viruses. In an electronmicroscopic study, the transendothelial migration of mononuclear cells was observed on monolayered endothelial cells infected with virus. This results suggested that the endothelial adhesion molecules, particulary VCAM and ICAM, might be expressed on endothelial cells by infection with Hantaan virus and these molecules play a key role in the adhesion and extravasation of inflammatory cells around blood vessels.

• Molecules and Cells
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• v.39 no.7
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• pp.557-565
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• 2016

The paired immunoglobulin-like type 2 receptor (PILR) family consists of two functionally opposite members, inhibitory $PILR{\alpha}$ and activating $PILR{\beta}$ receptors. PILRs are widely expressed in various immune cells and interact with their ligands, especially CD99 expressed on activated T cells, to participate in immune responses. Here we investigated whether PILR-derived agonists inhibit ${\beta}1$ integrin activity as ligands for CD99. PILR-derived peptides as well as PILR-Fc fusion proteins prevented cell adhesion to fibronectin through the regulation of ${\beta}1$ integrin activity. Especially, PILRpep3, a representative 3-mer peptide covering the conserved motifs of the PILR extracellular domain, prevented the clustering and activation of ${\beta}1$ integrin by dephosphorylating FAK and vinculin, which are major components of focal adhesion. In addition, PILRpep3 inhibited transendothelial migration of monocytes as well as endothelial cell tube formation. Furthermore, upon intraperitoneal injection of PILRpep3 into mice with collagen-induced arthritis, the inflammatory response of rheumatoid arthritis was strongly suppressed. Taken together, these results suggest that PILR-derived agonist ligands may prevent the inflammatory reactions of rheumatoid arthritis by activating CD99.