In Vitro Cytotoxicity Model of Particulate Matter on Human Red Blood

我们的结果表明，二氧化钛颗粒在溶液中的悬浮方法会影响到颗粒对红细胞(RBC)或任何其他细胞系的作用，因此必须采用精确的标准分散方法。我们以前的实验和目前的结果表明，任何形式的二氧化钛都会引起溶血。虽然颗粒大小是决定二氧化钛溶血程度的重要因素，但颗粒的类型或晶型起着更重要的作用。我们通过检测颗粒对谷胱甘肽氧化和脂质过氧化的影响来研究氧化应激在二氧化钛诱导的溶血中的作用，结果是不确定的。初步的红细胞膜电泳实验表明，二氧化钛颗粒可能对一种被认为是粘附素的低分子量蛋白质产生影响。然而，这些结果的较差的重复性阻碍了我们对这一发现的证实。二氧化钛颗粒作用于A549肺上皮细胞可引起剂量依赖性的凋亡，IL-8mRNA和IL-8蛋白的释放略有增加，但对核因子-kB DNA没有影响。

Our results suggest that the method of suspension of titanium dioxide (TiO2) particles in solution influences the effects of the particles on red blood cells (RBCs) or any other cell line, therefore precise and standard dispersion methods must be employed. Our previous experiments and the current results demonstrate that any form of TiO_2 causes hemolysis. Although particle size is an important determinant of the level of hemolysis induced by TiO2, the particle type or polymorph plays a more significant role.We investigated the involvement of oxidative stress in TiO2-induced hemolysis by examining the effects of particles on glutathione oxidation and lipid peroxidation, and the results were inconclusive.Preliminary electrophoresis experiments with RBC membranes showed a probable effect of the TiO_2 particles on a low molecular weight protein, which was considered to be Cofilin. However, poor reproducibility of these results hindered our confirmation of this finding.TiO2 particles exposed to A549 lung epithelial cells caused dose-dependent apoptosis, slight increase in the release of IL-8 mRNA and IL-8 protein, but no effects on NF-kB DNA.