磷酸三(2,3-二氯丙基)酯和纳米二氧化钛联合暴露诱导斑马鱼胚胎细胞凋亡

Combined exposure of tris(2,3-dichloropropyl)phosphate and nano-TiO_(2) induces apoptosis of zebrafish embryos

鉴于纳米二氧化钛(nano-TiO_(2))与其他污染物共存会改变共存物的生物利用性及毒性,大量应用的阻燃剂磷酸三(1,3-二氯-2-丙基)酯(TDCIPP)与nano-TiO_(2)在水环境中共存性极高,共存物可能对人类健康带来不可预知的风险.本文研究了TDCIPP和nano-TiO_(2)对模式生物斑马鱼胚胎的复合毒性,重点考察了二者复合诱发的细胞凋亡.通过吖啶橙染色法直观观察凋亡细胞,测定细胞凋亡酶以及凋亡功能基因的表达分析诱发凋亡的潜在机制.结果显示,TDCIPP单一暴露能够诱导幼鱼发生凋亡,凋亡率呈剂量依赖关系.凋亡酶Caspase-3、Caspase-9和p 53、Bax也显著上调.数据表明TDCIPP单一暴露p 53上调,复合暴露组基因表达也一样,其中TDCIPP单独暴露与空白组相比分别增加了0.89、1.64、2.12和2.61倍.TDCIPP与nano-TiO_(2)共同暴露时导致斑马鱼细胞凋亡的趋势与TDCIPP单一暴露相似,但是诱发斑马鱼细胞凋亡趋势降低.结果表明,nano-TiO_(2)能够减轻TDCIPP诱导斑马鱼胚胎的细胞凋亡.

In view of the fact that the coexistence of nano-TiO_(2) and other pollutants will change the bioavailability and toxicity of the coexistence,the widely used flame retardant tris(1,3-dichloro-2-propyl)phosphate(TDCIPP)and nano-TiO_(2) have a very high coexistence in the water environment,and the coexistence may bring unpredictable risks to human health.In this study,we studied the combined toxicity of TDCIPP and nano-TiO_(2) on zebrafish embryos,with emphasis on the apoptosis induced by the combination of TDCIPP and nano-TiO_(2).The apoptotic cells were observed directly by acridine orange staining,and the expression of apoptotic enzymes and apoptotic functional genes were determined to analyze the potential mechanism of inducing apoptosis.The results showed that the single exposure of TDCIPP could induce apoptosis in juvenile fish in a dose dependent manner.The apoptotic enzymes Caspase-3,Caspase-9,p 53 and Bax were also significantly up-regulated.The data showed that p 53 was upregulated in the TDCIPP single exposure group,as well as in the combined exposure group,where TDCIPP exposure alone was associated with 0.89,1.64,2.12 and 2.61 fold increases in gene expression compared to the blank group,respectively.The co exposure of TDCIPP and nano-TiO_(2) led to the apoptosis of zebrafish cells in a similar trend to the single exposure of TDCIPP,but the apoptotic trend of zebrafish cells was reduced.The results showed that nano-TiO_(2) could reduce the apoptosis of zebrafish embryos induced by TDCIPP.