Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, Japan.
Ind Health. 2011;49(3):344-52. doi: 10.2486/indhealth.ms1218. Epub 2011 Mar 1.
In order to investigate whether or not dispersed nanoparticles have an effect of inflammation and fibrosis on animals, we developed a nanoparticle generation system and examined the gene expression of matrix metalloproteinase (MMP) and tissue inhibitor matrix proteinase (TIMP) in rat lung containing inhaled nickel oxide (NiO) or titanium dioxide (TiO(2)) nanoparticles. In both experiments, Wistar male rats were exposed to NiO or TiO(2) nanoparticles for 4 wk (6 h/day). The geometric mean diameters of NiO and TiO(2) in the chamber were 139 ± 12 nm and 51 ± 9 nm, respectively. The average concentration of the particle number of NiO and TiO(2) was 1.0E+05 /cm(3) and 2.8E+05 /cm(3), respectively. At 4 d, 1 and 3 months after the end of the inhalation, the rats exposed to these particles were sacrificed and the gene expressions of MMP-2, TIMP-2 and type I collagen were measured using RT-PCR. Pathological finding revealed that there was minimum inflammation with nickel oxide only at 4 d and no change with titanium oxide. However, there were no changes of the gene expression of MMP-2, TIMP-2, and type I collagen in either the NiO or TiO(2) exposure groups. In this study, inhalation of nickel oxide and titanium dioxide nanoparticles did not induce the gene expression of MMP-2 and TIMP-2 mRNA in rat lungs.
为了研究分散的纳米颗粒是否会对动物产生炎症和纤维化的影响，我们开发了一种纳米颗粒生成系统，并检测了吸入氧化镍（NiO）或二氧化钛（TiO(2)）纳米颗粒的大鼠肺中基质金属蛋白酶（MMP）和组织抑制剂基质蛋白酶（TIMP）的基因表达。在这两项实验中，Wistar 雄性大鼠暴露于 NiO 或 TiO(2)纳米颗粒中 4 周（每天 6 小时）。室内 NiO 和 TiO(2)的几何平均粒径分别为 139 ± 12nm 和 51 ± 9nm。NiO 和 TiO(2)的颗粒数平均浓度分别为 1.0E+05 /cm(3)和 2.8E+05 /cm(3)。在吸入结束后的第 4 天、1 个月和 3 个月，处死暴露于这些颗粒的大鼠，并用 RT-PCR 测量 MMP-2、TIMP-2 和 I 型胶原的基因表达。病理学发现，仅在第 4 天观察到镍氧化物引起的最小炎症，而钛氧化物没有变化。然而，在 NiO 或 TiO(2)暴露组中，MMP-2、TIMP-2 和 I 型胶原的基因表达均无变化。在这项研究中，吸入镍氧化物和二氧化钛纳米颗粒不会诱导大鼠肺中 MMP-2 和 TIMP-2 mRNA 的基因表达。
