Comprehensive toxioological assessment of fibrous particles by differential gene expression.

通过差异基因表达对纤维颗粒进行综合毒理学评估。

• 批准号: 11680563
• 负责人: HIRANO Seishiro
• 金额: $ 2.37万
• 依托单位: National Institute for Environmental Studies
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11680563/
• 关键词: Titanium oxide; Alveolar macrophage; Differential-display; Phagocytosis; krox20; egr-2; Northern hybridization; PCR; F ibrous particle; アスベスト; 浮遊粒子状物質; 肺胞マイクロファージ; デイファレンシャル-デイスプレイ; Krox-20; ノーザンハイブリダイゼーション

The present study was designed to study differences in biological responses of alveolar macrophages between phagocytosis of he spherical and fibrous particles. Although titanium dioxide is thought to be biologidlay inert, the cytotoxicity of fibrous titanium dioxide (FTiO2) was much higher than spherical TiO2 (STiO2). Differential display and the following Northern blot analysis indicated that transcription of krox2O/egr-2 gene was slightly and greatly upregulated in S and F-TiO2-exposed alveolar macrophages, repectively. The mRNA level of krox20/egr-2 ineased up to 8 hr, when alveolar macrophages were exposed to FTiO2. Quite interestingly the krox20/egr-2 mRNA level was transiently increased, when alveolar macrophages were plated into the culture dish. The analysis with 5' rapid amplification of cDNA ends (5'TACE) suggested that there is a heterogeneity in the upstream region of this gene (Krox20/egr-2 and krox20H1 ; acassion numbers AB032120 and AB032419, respectively). The PCR analysis with specific primers for krox-20/egr-2 and krox20H1 indicated that both genes were almost equally upregulated following either adhesion to the plastic dish or phagocytosis of FTiO2. Picetannol, a Syk kinase inhibitor, completely inhibited the krox20/egr-2 gene expression. These results suggest that tyrosine phosphorylation is implicated in adhesion and phagocytosis of alveolar macrophages, and the expression of krox20/egr-2 may reflect interaction of alveolar macrophages with foreign substances.

本研究旨在研究肺泡巨噬细胞吞噬球形颗粒和纤维状颗粒的生物学反应差异。虽然二氧化钛被认为是生物惰性的，但纤维状二氧化钛（FTiO 2）的细胞毒性远高于球形二氧化钛（STiO 2）。差异显示和随后的北方印迹分析表明，S和F-TiO_2暴露的肺泡巨噬细胞中krox_（2 O）/krox-2基因的转录分别轻微和显著上调。肺巨噬细胞暴露于FTIO_2后，krox 20/krox 2的mRNA水平在8小时内升高。非常有趣的是，当肺泡巨噬细胞接种到培养皿中时，krox 20/krox 2 mRNA水平瞬时增加。5'端快速扩增cDNA末端（5' TACE）分析表明，该基因上游区域存在异质性（Krox 20/Krox 20 -2和Krox 20-H1，序列号分别为AB 032120和AB 032419）。用krox-20/krox-2和krox 20 H1的特异性引物进行的PCR分析表明，无论是粘附到塑料培养皿上还是FTiO 2的吞噬作用下，这两个基因几乎同样地上调。Syk激酶抑制剂Picetannol可完全抑制krox 20/krox 2基因的表达。提示酪氨酸磷酸化参与了肺泡巨噬细胞的粘附和吞噬功能，krox 20/krox 2的表达可能反映了肺泡巨噬细胞与外源性物质的相互作用。

项目成果

Hiroki Kitajima,Seishiro Hirano,Kazuo T.Suzuki: "Upregulation of heme oxygenase gene expressio in rat lung epithelial cells following exposure to cadmium"Arch Toxicol. 73. 410-412 (1999)

Hiroki Kitajima、Seishiro Hirano、Kazuo T.Suzuki：“接触镉后大鼠肺上皮细胞血红素加氧酶基因表达上调”Arch Toxicol。

Seishiro Hirano, Mitsuru Ando, Sanae Kanno: "Inflammatory responses of rat alveolar macrophages following exposure to fluoride."Arch Toxicol.. 73. 310-315 (1999)

Seishiro Hirano、Mitsuru Ando、Sanae Kanno：“暴露于氟化物后大鼠肺泡巨噬细胞的炎症反应。”Arch Toxicol.. 73. 310-315 (1999)

Hiroki Kitajima, Seishiro Hirano, Kazuo T.Suzuki: "Upregulation of heme oxygenase gene expressio in rat lung epithelial cells following exposure to cadmium"Arch Toxicol.. 73. 410-412 (1999)

Hiroki Kitajima、Seishiro Hirano、Kazuo T.Suzuki：“暴露于镉后大鼠肺上皮细胞中血红素加氧酶基因表达的上调”Arch Toxicol.. 73. 410-412 (1999)