Inhibitors of tryptase as mast cell-stabilizing agents in the human airways:: Effects of tryptase and other agonists of proteinase-activated receptor 2 on histamine release
Inhibitors of tryptase as mast cell-stabilizing agents in the human airways:: Effects of tryptase and other agonists of proteinase-activated receptor 2 on histamine release
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DOI：
10.1124/jpet.103.061291
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发表时间：
2004-04-01
影响因子：
3.5
通讯作者：
Walls, AF
中科院分区：
文献类型：
--
作者：
He, SH;Aslam, A;Walls, AF
类胰蛋白酶是人类肥大细胞的主要分泌产物，正在成为过敏性气道疾病治疗干预的新靶点。我们研究了类胰蛋白酶和类胰蛋白酶抑制剂调节人肺肥大细胞释放组胺的能力，并研究了蛋白酶激活受体 2 (PAR2) 的潜在贡献。类胰蛋白酶抑制剂 APC366 [N-(1-羟基-2-萘甲酰基)-L-精氨酰-L-脯氨酰胺盐酸盐] 能够非常有效地抑制抗 IgE 抗体或钙离子载体从酶促分散的人肺细胞中刺激的组胺释放。低至 10 μM 的 APC366 浓度能够抑制抗 IgE 依赖性组胺释放约 50%。添加亮肽素或胰蛋白酶底物 N-苯甲酰-D,L-精氨酸-对硝基苯胺也抑制 IgE 依赖性组胺释放。纯化的类胰蛋白酶在肝素存在下刺激肺细胞少量但显着地释放组胺，这表明类胰蛋白酶可以提供来自可能对蛋白酶抑制剂敏感的活化细胞的放大信号。胰蛋白酶还能够通过催化机制明显诱导组胺释放。此外，用代谢抑制剂或百日咳毒素预处理细胞会降低反应，表明非细胞毒性百日咳毒素敏感的 G 蛋白介导的信号传导过程。向细胞添加PAR2激动剂SLIGKV-NH2或tc-LIGRLO-NH2或适当的对照肽对组胺释放没有影响，并且通过免疫组织化学在组织肥大细胞中未检测到PAR2。类胰蛋白酶抑制剂作为肥大细胞稳定剂的有效作用可能对治疗呼吸道过敏性炎症有价值，可能是通过靶向类胰蛋白酶的非 PAR2 介导的作用。
Tryptase, the major secretory product of human mast cells, is emerging as a new target for therapeutic intervention in allergic airways disease. We have investigated the ability of tryptase and inhibitors of tryptase to modulate histamine release from human lung mast cells and have examined the potential contribution of proteinase-activated receptor 2 (PAR2). The tryptase inhibitor APC366 [N-(1-hydroxy-2-naphthoyl)-L-arginyl-L-prolinamide hydrochloride] was highly effective at inhibiting histamine release stimulated by anti-IgE antibody or calcium ionophore from enzymatically dispersed human lung cells. A concentration of APC366 as low as 10 muM was able to inhibit anti-IgE-dependent histamine release by some 50%. Addition of leupeptin or the tryptic substrate N-benzoyl-D, L-arginine-p-nitroanilide also inhibited IgE-dependent histamine release. Purified tryptase in the presence of heparin stimulated a small but significant release of histamine from lung cells, suggesting that tryptase may provide an amplification signal from activated cells that may be susceptible to proteinase inhibitors. Trypsin was also able to induce histamine release apparently by a catalytic mechanism. Moreover, pretreatment of cells with metabolic inhibitors or with pertussis toxin reduced responses, indicating a noncytoxic pertussis toxin-sensitive G protein-mediated signaling process. Addition to cells of the PAR2 agonists SLIGKV-NH2 or tc-LIGRLO-NH2 or appropriate control peptides were without effect on histamine release, and PAR2 was not detected by immunohistochemistry in tissue mast cells. The potent actions of tryptase inhibitors as mast cell-stabilizing agents could be of value in the treatment of allergic inflammation of the respiratory tract, possibly by targeting the non-PAR2-mediated actions of tryptase.