• Title/Summary/Keyword: adhesion molecules

Search Result 335, Processing Time 0.032 seconds

P-Selectin-mediated Acute Inflammation Can Be Blocked by Chemically Modified Heparin, RO-Heparin

  • Gao, Yanguang;Li, Na;Fei, Rui;Chen, Zhihong;Zheng, Sheng;Zeng, Xianlu
    • Molecules and Cells
    • /
    • v.19 no.3
    • /
    • pp.350-355
    • /
    • 2005
  • Selectins are carbohydrate-binding cell adhesion molecules that play a major role in the initiation of inflammatory responses. Heparin can bind to P-selectin, and its anti-inflammatory property is mainly due to inhibition of P-selectin. However, the strong anticoagulant activity of heparin limits its clinical use. We prepared periodate-oxidized, borohydride-reduced heparin (RO-heparin) by chemical modification and tested its anticoagulant and anti-inflammatory activities. Activated partial thromboplastin time (aPTT) assays showed that, compared with heparin, RO-heparin had greatly reduced anticoagulant activity. Intravenous administration of this compound led to reduction in the peritoneal infiltration of neutrophils in a mouse acute inflammation model. In vitro cell adhesion experiments demonstrated that the effect of RO-heparin on inflammatory responses was mainly due to inhibiting the interaction of P-selectin with its ligands. These results indicate that RO-heparin may be a safer treatment for inflammation than heparin, especially when selectin is targeted.

Protein tyrosine phosphatase PTPRT as a regulator of synaptic formation and neuronal development

  • Lee, Jae-Ran
    • BMB Reports
    • /
    • v.48 no.5
    • /
    • pp.249-255
    • /
    • 2015
  • PTPRT/RPTPρ is the most recently isolated member of the type IIB receptor-type protein tyrosine phosphatase family and its expression is restricted to the nervous system. PTPRT plays a critical role in regulation of synaptic formation and neuronal development. When PTPRT was overexpressed in hippocampal neurons, synaptic formation and dendritic arborization were induced. On the other hand, knockdown of PTPRT decreased neuronal transmission and attenuated neuronal development. PTPRT strengthened neuronal synapses by forming homophilic trans dimers with each other and heterophilic cis complexes with neuronal adhesion molecules. Fyn tyrosine kinase regulated PTPRT activity through phosphorylation of tyrosine 912 within the membrane-proximal catalytic domain of PTPRT. Phosphorylation induced homophilic cis dimerization of PTPRT and resulted in the inhibition of phosphatase activity. BCR-Rac1 GAP and Syntaxin-binding protein were found as new endogenous substrates of PTPRT in rat brain. PTPRT induced polymerization of actin cytoskeleton that determined the morphologies of dendrites and spines by inhibiting BCR-Rac1 GAP activity. Additionally, PTPRT appeared to regulate neurotransmitter release through reinforcement of interactions between Syntaxin-binding protein and Syntaxin, a SNARE protein. In conclusion, PTPRT regulates synaptic function and neuronal development through interactions with neuronal adhesion molecules and the dephosphorylation of synaptic molecules. [BMB Reports 2015; 48(5): 249-255]

Hydroquinone, a Reactive Metabolite of Benzene, Reduces Macrophage-mediated Immune Responses

  • Lee, Ji Yeon;Kim, Joo Young;Lee, Yong Gyu;Shin, Won Cheol;Chun, Taehoon;Rhee, Man Hee;Cho, Jae Youl
    • Molecules and Cells
    • /
    • v.23 no.2
    • /
    • pp.198-206
    • /
    • 2007
  • Hydroquinone is a toxic compound and a major benzene metabolite. We report that it strongly inhibits the activation of macrophages and associated cells. Thus, it suppressed the production of proinflammatory cytokines [tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-$1{\beta}$, IL-3, IL-6, IL-10, IL-12p40, IL-23], secretion of toxic molecules [nitric oxide (NO) and reactive oxygen species (ROS)] and the activation and expression of CD29 as judged by cell-cell adhesion and surface staining experiments. The inhibition was due to the induction of heme oxygenase (HO)-1 in LPS-activated macrophages, since blocking HO-1 activity with ZnPP, an HO-1 specific inhibitor, abolished hydroquinone's NO inhibitory activity. In addition, hydroquinone and inhibitors (wortmannin and LY294002) of the phosphatidylinositol-3 kinase (PI3K)/Akt pathway had very similar inhibitory effects on LPS-induced and CD29-mediated macrophage responses, including the phoshorylation of Akt. Therefore, our data suggest that hydroquinone inhibits macrophage-mediated immune responses by modulating intracellular signaling and protective mechanisms.

Genipin Selectively Inhibits TNF-${\alpha}$-activated VCAM-1 But Not ICAM-1 Expression by Upregulation of PPAR-${\gamma}$ in Human Endothelial Cells

  • Jung, Seok-Hwa;Mun, Lidiya;Kim, Hye-Jung;Seo, Han-Geuk;Lee, Jae-Heun;Kwak, Jong-Hwan;Lee, Dong-Ung;Chang, Ki-Churl
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.15 no.3
    • /
    • pp.157-162
    • /
    • 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.

Heparin Attenuates the Expression of TNF $\alpha$-induced Cerebral Endothelial Cell Adhesion Molecule

  • Lee, Jeong-Ho;Kim, Chul-Hoon;Seo, Gi-Ho;Lee, Jin-U;Kim, Joo-Hee;Kim, Dong-Goo;Ahn, Young-Soo
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.12 no.5
    • /
    • pp.231-236
    • /
    • 2008
  • Heparin is a well-known anticoagulant widely used in various clinical settings. Interestingly, recent studies have indicated that heparin also has anti-inflammatory effects on neuroinflammation-related diseases, such as Alzheimer's disease and meningitis. However, the underlying mechanism of its actions remains unclear. In the present study, we examined the anti-inflammatory mechanism of heparin in cultured cerebral endothelial cells (CECs), and found that heparin inhibited the tumor necrosis factor $\alpha$ ($TNF{\alpha}$)-induced and nuclear factor kappa B (NF-${\kappa}B$)-dependent expression of adhesion molecules, such as intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), which are crucial for inflammatory responses. Heparin selectively interfered with NF-${\kappa}B$ DNA-binding activity in the nucleus, which is stimulated by $TNF{\alpha}$. In addition, non-anticoagulant 2,3-O desulfated heparin (ODS) prevented NF-${\kappa}B$ activation by $TNF{\alpha}$, suggesting that the anti-inflammatory mechanism of heparin action in CECs lies in heparin's ability to inhibit the expression of cell adhesion molecules, as opposed to its anticoagulant actions.

Inhibitory Effects of Ojeoksan on TNF-α-induced Vascular Inflammation in Human Umbilical Vein Endothelial Cells (TNF-α로 유도된 혈관내피세포의 혈관염증에 미치는 오적산(五積散)의 억제 효과)

  • Han, Byung Hyuk;Yoon, Jung Joo;Kim, Hye Yoom;Ahn, You Mee;Hong, Mi Hyeon;Son, Chan Ok;Na, Se Won;Lee, Yun Jung;Gang, Dae-Gil;Lee, Ho Sub
    • The Korea Journal of Herbology
    • /
    • v.33 no.4
    • /
    • pp.59-67
    • /
    • 2018
  • Objectives : Ojeoksan, originally recorded in an ancient Korean medicinal book named "Donguibogam" and has been used for the treatment of circulation disorder of blood which was called blood accumulation (血積) in Korean medicine. Therefore, this study was carried out to investigate the beneficial effect of OJS on vascular inflammation in HUVECs. Methods : We evaluated the effect of OJS on the expression of cell adhesion molecules and protective role in HUVEC stimulated by TNF-${\alpha}$ by using Western blot. Results : Pretreatment with OJS decreased the adhesion of HL-60 cells to TNF-${\alpha}$-induced HUVEC. OJS suppressed TNF-${\alpha}$-induced expression level of cell adhesion molecules such as intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1(VCAM-1), and endothelial cell selectin (E-selectin). Moreover, OJS significantly decreased TNF-${\alpha}$-induced production of intracellular reactive oxygen species (ROS); and inhibited the phosphorylation of $I{\kappa}B-{\alpha}$ in the cytoplasm compared to the experimental group. Pretreatment with OJS inhibited the trans-location of NF-${\kappa}B$ p65 to the nucleus. OJS also inhibited phosphorylation of MAPKs compared to the experimental group. OJS significantly increased the protein expression of Nrf2 and HO-1. Conclusions : Ojeoksan has a protective effect on vascular inflammation, and might be a potential therapeutic agent for early atherosclerosis.

Effect of Ginsenoside Rb1 on Cell Adhesion, Surface Molecule Expression and Morphological Changes (Ginsenoside Rb1의 세포간 유착, 세포표면 단백질 발현 및 세포형태변화에 미치는 효과)

  • Kim, Byung-Hun;Cho, Jae-Youl
    • Journal of Ginseng Research
    • /
    • v.33 no.4
    • /
    • pp.330-336
    • /
    • 2009
  • Cell-cell adhesion managed by various adhesion molecules is known to be one of important phenomena found in numerous immunological responses or diseases such as immunostimulation, rheumatoid arthritis and allergic diseases. In this study, we examined the regulatory role of ginsenosides (G)-Rb1, reported to display immunostimulatory and anticancer effects, on cell adhesion, the up-regulation of surface adhesion molecules and morphological changes using monocytic U937 and macrophage-like RAW264.7 cells. G-Rb1 significantly up-regulated U937 cell-cell adhesion mediated by both CD29 and CD43. It also enhanced U937 cell-fibronectin adhesion, while CD29 blocking antibody P5D2 strongly suppressed it. In agreement, this compound also significantly increased the surface level of CD29 as well as CD43. Furthermore, this compound differentially modulated CD82 up-regulation and morphological changes triggered by lipopolysaccharide (LPS) and phorbol-12-myristate-13-acetate (PMA). Therefore, these results suggest that G-Rb1 may have differential modulatory function on cell adhesion events, surface molecule expression and morphological changes responsible for immune responses.

Delphinidin Chloride Effects on the Expression of TNF-$\alpha$ Induced Cell Adhesion Molecules (TNF-$\alpha$에 의해 유도된 세포부착분자의 발현에 대한 Delphinidin chloride의 억제 효과)

  • Koh, Eun-Gyeong;Chae, Soo-Chul;Seo, Eun-Sun;Na, Myung-Suk;Lee, Jong-Bin
    • Korean Journal of Environmental Biology
    • /
    • v.27 no.1
    • /
    • pp.88-94
    • /
    • 2009
  • The process of atherosclerosis begins through secretion of inflammatory cytokine or adhesion of leukocyte from damage in blood vessels and transmigration. This study was conducted to investigate the effects of delphinidin chloride (DC) in the initial process of atherosclerosis on the expression of ICAM-1 (Intracellular Adhesion Molecule-1) and VCAM-1 (Vascular Adhesion Molecule-1) related to adhesion of leukocyte at the HUVEC (human umbilical vein endothelial cell line. As a result, cell growth inhibition rate at 50 ${\mu}M$ was respectively 4, 3 and 5% without cell toxicity. As a result of morphological observation monocyte-endothelial cell adhesion assay and optical microscope carried out to measure attachment of mononuclear cells to endothelial cells induced by Tumor necrosis factor-alpha (TNF-$\alpha$) at concentrations without cell toxicity, DC concentration-dependently suppressed attachment. When effects on the expression of VCAM-1 and ICAM-1, cell adhesion molecules induced from endothelial cells by TNF-$\alpha$, were comparatively analyzed using western blot analysis and RT-PCR methods, protein of VCAM-1 and ICAM-1 and expression at the level of mRNA were concentration-dependently reduced. Taken together, the results of this studies provide evidence that DC possess an anti-metastatic activity.

Anti-cell Adhesion Effect of PLM-f74 with U937 Cell from Hallophilic Enterobacteria and Identification of Strain

  • Lim, Jong-Kwon;Seo, Hyo-Jin;Shin, Jin-Hyuk;Lee, Se-Young;Kim, Min-Yong;Kim, Jong-Deog
    • 한국생물공학회:학술대회논문집
    • /
    • 2005.10a
    • /
    • pp.406-411
    • /
    • 2005
  • Fermented materials with enterobacteria isolated from fusiform fish, have strong anti-angiogenesis effect and anti-cell adhesion effect. PLM-f74 got from 74th fraction of size exclusion chromatography from fermented material, showed strong anti-cell adhesion effect between HUVECs and U937 monocytic cell. Adhesion of U937 cell to HUVEC stimulated with IL-1b was clearly inhibited by PLM-f74 in a dose-dependent manner by 12.1, 21.2, 50.9, and 78.2%, when U937 cells treated with each of the PLM-f74 and stimulated with PMA (100 mg/L) was added onto untreated and unstimulated HUVECs, adhesion was observed by 15.8, 31.9, 70.8, and 102%, when both cell types were pretreated with PLM-f74, the adhesion was prominently decreased by 83.7, 99.2, 110, and 120.8%, with 0.74, 3.7, 7.4, and 18.5ug/mL of PLM-f74, respectively. PLM-f74, also, reduced IL-1-stimulated HUVEC expression of adhesion molecules, VCAM-1, ICAM-1, and E-selectin dose-dependently by ELISA method.

  • PDF