Genomic and non-genomic effects of dexamethasone on equine peripheral blood neutrophils
Genomic and non-genomic effects of dexamethasone on equine peripheral blood neutrophils
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DOI：
10.1016/j.vetimm.2008.10.303
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发表时间：
2009-03-15
影响因子：
1.8
通讯作者：
Lavoie, J. -P.
中科院分区：
文献类型：
--
作者：
Lecoq, L.;Vincent, P.;Lavoie, J. -P.
背景：糖皮质激素具有有效的抗炎特性，经常用于治疗家畜物种，包括马。它们通过基因组和非基因组效应诱导多种炎症途径的下调。目前，关于糖皮质激素对马外周血中性粒细胞的影响知之甚少。假设：地塞米松（DEX）是一种强效合成糖皮质激素，通过基因组和非基因组效应抑制马外周血中性粒细胞的功能。动物：六匹健康成年混种母马。方法：评估 DEX，使用梯度技术分离外周血中性粒细胞，并与100 ng/ml LPS和10(-6)M DEX单独孵育6小时，或与糖皮质激素受体(GR)抑制剂RU486(10(-5)M)联用。使用实时 RT-PCR 测量 IL-8、TNF-α 和 TLR-4 的信使 RNA。在用5 ng/ml佛波醇肉豆蔻酸酯乙酸酯刺激前5、10和15分钟，在用5μM二氯二氢荧光素(DCF)和10(-6)M DEX孵育的中性粒细胞中研究了DEX的非基因组效应。中性粒细胞同样与 DEX（10(-6) M，15 分钟）和 RU486（10-5 M）共同孵育，以评估 GR 对这些效应的贡献。使用流式细胞术研究 DCF 的氧化。结果：用 LIPS 刺激中性粒细胞导致 IL-8、TNF-α 和 TLR-4 mRNA 表达显着增加 (p < 0.0001)；与 DEX 一起孵育显着下调了这一过程 (p < 0.0001)。孵育 10 分钟和 15 分钟后，DEX 显着减少 DCF 的氧化（p < 0.0001）。这些作用是通过GRs介导的。结论：DEX通过基因组和非基因组途径对马外周血中性粒细胞发挥抗炎作用。 (C) 2008 Elsevier B.V. 保留所有权利。
Background: Glucocorticoids have potent anti-inflammatory properties and are frequently used for the treatment of domestic animal species, including horses. They induce a down-regulation of multiple inflammatory pathways through both genomic and non-genomic effects. Currently, little is known on the effects of glucocorticoids on equine peripheral blood neutrophils.Hypothesis: Dexamethasone (DEX), a potent synthetic glucocorticoid, inhibits the functions of equine peripheral blood neutrophils through both genomic and non-genomic effects.Animals: Six healthy adult mixed breed female horses.Methods: To assess the genomic effects of DEX, peripheral blood neutrophils were isolated using a gradient technique and incubated 6 h with 100 ng/ml LPS and 10(-6) M DEX alone, or combined with the glucocorticoid receptor (GR) inhibitor RU486 (10(-5) M). Messenger RNA for IL-8, TNF-alpha and TLR-4 were measured using real-time RT-PCR. The non-genomic effects of DEX were studied in neutrophils incubated with 5 mu M dichlorodihydrofluorescein (DCF) and 10(-6) M DEX 5, 10 and 15 min prior to being stimulated with 5 ng/ml phorbol myristate acetate. Neutrophils were similarly co-incubated with DEX (10(-6) M, 15 min) and RU486 (10-5 M) to evaluate the contribution of the GR to these effects. The oxidation of DCF was studied using flow-cytometry.Results: Neutrophils stimulation with LIPS resulted in a significant increase in IL-8, TNF-alpha and TLR-4 mRNA expressions (p < 0.0001); incubation with DEX significantly down-regulated this process (p < 0.0001). DEX significantly reduced oxidation of DCF after 10 and 15 min of incubation (p < 0.0001). Those effects were mediated through the GRs.Conclusion: DEX exerts anti-inflammatory effects on equine peripheral blood neutrophils through both genomic and non-genomic pathways. (C) 2008 Elsevier B.V. All rights reserved.