In vitro toxicity of asbestos substitutes evaluated by cytomagnetometry

通过细胞磁力测定法评估石棉替代品的体外毒性

基本信息

批准号：
11470099
负责人：
AIZAWA Yoshiharu
金额：
$ 4.48万
依托单位：
Kitasato University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

项目摘要

Recently, some asbestos substitutes have been used in Japan, as health disorders occurred by asbestos had been known. However, such substitutes have not proved their safety yet, and it is important to establish screening methods for evaluating health disorders. Then we examined a few evaluations of health disorders for silicon carbide whisker (SiC), titanium dioxide whisker (TiO_2) and rock wool (RW) not only by cytomagnetometry, but also by LDH release assays, morphological observations and apoptotic observations.Both 20, 40, and 60 μg/ml of SiC and TiO_2 in the culture medium showed that relaxation was delayed dose-dependently and decay constants were smaller than those of negative controls. LDH release assay showed that releasing rates were increased dose-dependently. Morphological observations showed multiple vacuolations in cytosol, degenerations of nuclei, and agglutinations of chromatin. And apoptotic observations by using TUNEL method and DNA ladder method showed slight apoptotic cells in a sample added to SiC.On the other hand, 50, 100, and 150μg/ml of RW did not show delays of relaxation and decreasing of decay constants in comparison with negative controls. Results of LDH release assay, morphological observations including TUNEL method and DNA ladder method, and apoptotic observations supported results of cytomagnetometry.Then, it is found that an acute cytotoxicity of RW to alveolar macrophages is less than that of SiC and TiO_2 in in vitro experiments. In future, we are going to use subculture cells instead of alveolar macrophages obtained from bronchoalveolar lavage, to avoid changes in conditions of experiments. In order to observe a mechanism of relaxation optically, we will examine intracellular movements of magnetized particles after magnetization by using a video-enhanced microscope. In addition, cytotoxic evaluations of asbestos substitutes except SiC, TiO_2 and RW will be examined.

最近，日本已经使用了一些石棉替代品，因为众所周知的石棉发生了健康障碍。但是，这种替代品尚未证明其安全性，建立评估健康疾病的筛查方法很重要。 Then we examined a few evaluations of health disorders for silicon carbide whisker (SiC), titanium dioxide whisker (TiO_2) and rock wool (RW) not only by cytomagnetometry, but Also by LDH release assays, morphological observations and apoptotic observations.Both 20, 40, and 60 μg/ml of SiC and TiO_2 in the culture medium shown that松弛依赖剂量延迟，并且衰减常数小于阴性对照的常数。 LDH释放分析表明，释放率依赖性依赖性剂量。形态学观察结果显示在细胞质，核退化和染色质凝集中的多种空泡。使用TUNEL方法和DNA阶梯方法进行的凋亡观察结果在添加到SIC的样品中略微凋亡细胞，另一方面，RW 50、100和150μg/ml的RW与负面对照相比，没有显示出松弛和衰减常数的延迟。 LDH释放测定的结果，包括TUNEL方法和DNA梯子方法在内的形态学观察以及凋亡观测支持了细胞磁法的结果。然后，发现在体外实验中，RW对肺泡巨噬细胞的急性细胞毒性小于SIC和TIO_2。将来，我们将使用亚培养细胞，而不是从支气管肺泡灌洗中获得的肺泡巨噬细胞，以避免实验条件的变化。为了从光学上观察松弛的机制，我们将使用视频增强显微镜检查磁化后磁化颗粒的细胞内运动。此外，将检查除SIC，TIO_2和RW以外的石棉替代物的细胞毒性评估。