Publications by authors named "Toshimitsu Yamada"

YM-58483/BTP-2, 4-methyl-4'-[3,5-bis(trifluoromethyl)-1H-pyrazol-1-yl]-1,2,3-thiadiazole-5-carboxanilide, blocks the store-operated Ca2+ entry (SOCE) that mediates the activation of non-excitable cells. This study investigated the pharmacological profile and therapeutic potential of YM-58483 as anti-asthma drug. YM-58483 inhibited DNP antigen-induced histamine release from and leukotrienes (LTs) production in IgE-primed RBL-2H3 cells, a rat basophilic leukemia cell line, with IC50 values of 460 and 310 nM, respectively.

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T cells play a regulatory role in the pathogenesis of various immune and allergic diseases, including human asthma. Recently, it was reported that a pyrazole derivative, YM-58483 (BTP2), potently inhibits Ca(2+) release-activated Ca(2+) (CRAC) channels and interleukin (IL)-2 production in T cells. We investigated the effects of YM-58483 on T helper type 2 (Th2) cytokine production in vitro and antigen-induced airway asthmatic responses in vivo.

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YM-393059, (+/-)-N-(4,6-dimethylpyrimidin-2-yl)-4-[2-(4-methoxy-3-methylphenyl)-5-(4-methylpiperazin-1-yl)-4,5,6,7-tetrahydro-1H-indol-1-yl]benzenesulfonamide difumarate, is a novel phosphodiesterase (PDE) inhibitor that inhibited the PDE7A isoenzyme with a high potency (IC50=14 nM) and PDE4 with a moderate potency (IC50=630 nM). In a cell-based assay, YM-393059 was found to inhibit anti-CD3 antibody, Staphylococcal enterotoxin B, and phytohaemagglutinin-induced interleukin (IL)-2 production in mouse splenocytes with IC50 values ranging from 0.48 to 1.

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3,5-Bis(trifluoromethyl)pyrazole derivative (BTP2) or N-[4-3, 5-bis(trifluromethyl)pyrazol-1-yl]-4-methyl-1,2,3-thiadiazole-5-carboxamide (YM-58483) is an immunosuppressive compound that potently inhibits both Ca2+ influx and interleukin-2 (IL-2) production in lymphocytes. We report here that BTP2 dosedependently enhances transient receptor potential melastatin 4 (TRPM4), a Ca2+-activated nonselective (CAN) cation channel that decreases Ca2+ influx by depolarizing lymphocytes. The effect of BTP2 on TRPM4 occurs at low nanomolar concentrations and is highly specific, because other ion channels in T lymphocytes are not significantly affected, and the major Ca2+ influx pathway in lymphocytes, ICRAC, is blocked only at 100-fold higher concentrations.

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CC chemokine ligand 11 (CCL11/eotaxin) and other CC chemokine receptor 3 (CCR3) ligands (CCL24/eotaxin-2, CCL26/eotaxin-3, CCL13/monocyte chemotactic protein-4, etc.) play important roles in the chemotaxis and activation of eosinophils and other CCR3-expressing cells (basophils, mast cells, and CD4(+) T helper 2 cells) in allergic inflammation incidents, including asthma and rhinitis. A newly synthesized compound, N-{(3R)-1-[(6-fluoro-2-naphthyl)methyl]pyrrolidin-3-yl}-2-{1-[(5-hydroxy-3-methylpyridin-2-yl)carbonyl]piperidin-4-ylidene}-acetamide hemifumarate (YM-355179), inhibited the binding of CCL11 and CCL5/regulated on activation normal T cell expressed and secreted to CCR3-expressing B300-19 cells with IC(50) values of 7.

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A newly synthesized compound, YM-90709, 2,3-dimethoxy-6,6-dimethyl-5,6-dihydrobenzo[7,8]indolizino[2,3-b]quinoxaline, was previously reported to specifically inhibit the binding of interleukin-5 (IL-5) to its receptor (R) on human eosinophils. In this study, the intravenous injection of YM-90709 inhibited antigen-induced infiltration of eosinophils into the bronchoalveolar lavage fluid (BALF) of BDF1 mice, with an ED(50) value of 0.050mg/kg.

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Interleukin-5 (IL-5) plays an important role in the activation of eosinophils in the allergic inflammation in conditions such as asthma, rhinitis, and atopic dermatitis. A newly synthesized compound, YM-90709 (2,3-dimethoxy-6,6-dimethyl-5,6-dihydrobenzo[7,8]indolizino[2,3-b]quinoxaline), was previously reported to inhibit the binding of IL-5 to its receptor (R) on human eosinophils and eosinophilic HL-60 clone 15 cells. However, it did not inhibit the binding of granulocyte-macrophage colony-stimulating factor (GM-CSF) to its receptor on the same cells.

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In nonexcitable cells, Ca(2+) entry is mediated predominantly through the store depletion-dependent Ca(2+) channels called store-operated Ca(2+) (SOC) or Ca(2+) release-activated Ca(2+) channels. YM-58483, a pyrazole derivative, inhibited an anti-CD3 mAb-induced sustained Ca(2+) influx in acute T cell leukemia, Jurkat cells. But it did not affect an anti-CD3 mAb-induced transient intracellular Ca(2+) increase in Ca(2+)-free medium, nor anti-CD3 mAb-induced phosphorylation of phospholipase Cgamma1.

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Interleukin-5 (IL-5) plays an important role in the activation of eosinophils in allergic inflammation including asthma and atopic dermatitis. A newly synthesized compound, YM-90709, 2,3-dimethoxy-6,6-dimethyl-5,6-dihydrobenzo[7,8]indolizino [2,3-b]quinoxaline, is reported here to inhibit the binding of IL-5 to its receptor on peripheral human eosinophils and butyric acid-treated eosinophilic HL-60 clone 15 cells, with IC50 values of 1.0 and 0.

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The antimuscarinic profile of the experimental drug solifenacin/YM905 [(+)-(1 S,3' R)-quinuclidin-3'-yl 1-phenyl-1,2,3,4-tetrahydroisoquinoline-2-carboxylate] for the treatment of overactive bladder was compared with the commonly prescribed agent oxybutynin. In radioligand binding assays, p K(i) values of solifenacin for M(1), M(2), and M(3) receptors were 7.6, 6.

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Platelet-endothelial cell adhesion molecule-1 (PECAM-1) is expressed on the membrane of leukocytes and vascular endothelial cells. PECAM-1 has been shown to play an important role in the process of leukocyte transmigration in various animal models of acute inflammation. We investigated the role of PECAM-1 in the progression of arthritis by systemically administering anti-murine PECAM-1 monoclonal antibody, 2H8, to DBA/1J mice with collagen-induced arthritis (CIA).

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