碲化镉量子点对小鼠肝脏的氧化损伤作用研究

目的探讨碲化镉量子点(CdTe QDs)对小鼠肝脏的氧化损伤作用。方法将40只雄性ICR小鼠随机分为5组,每组8只,尾静脉注射染毒。染毒浓度分别为0(对照)、0.5、5、50和500nmol/ml CdTe QDs溶液,每只动物注射0.2ml,对照组注射等体积的生理盐水,染毒24h后小鼠脱臼处死。采用生化方法检测肝脏组织匀浆中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性及丙二醛(MDA)含量,免疫组化法观察肝脏细胞8-羟基脱氧鸟嘌呤(8-OHdG)表达水平、TUNEL法检测肝细胞凋亡。结果 500nmol/ml CdTe QDs染毒组MDA含量与对照组比较显著增加(P<0.05);50和500nmol/ml CdTe QDs染毒组SOD活性与对照组比较显著降低(P<0.01);5、50和500nmol/ml CdTe QDs染毒组的CAT活性与对照组比较显著降低(P<0.01);免疫组化观察50、500nmol/ml CdTe QDs组肝细胞核内可见棕褐色的8-OHdG阳性颗粒表达,TUNEL法检测可见500nmol/ml CdTe QDs染毒组有少量凋亡细胞阳性颗粒表达出现。结论该实验条件下CdTe QDs可对小鼠肝脏组织产生氧化损伤作用,并有一定的剂量-效应关系。

Oxidative damage effects induced by CdTe quantum dots in mice liver

Objective To investigate oxidative damage effects induced by CdTe quantum dots(QDs) in mice liver.Methods 40 ICR mice were randomly divided into 5 groups,one control group(normal saline),four CdTe QDs(exposed by intravenous injection of 0.2ml CdTe QDs at the concentration of 0,0.5,5,50 and 500nmol/ml respectively).All mice were decapitated 24h after the injection.Concentration of MDA and the activities of SOD,CAT,8-OHdG expression were examined by immunohistochemistry and hepatocellular apoptosis was measured with TUNEL resperctively.Results The results showed in 500 nmol/ml CdTe QDs group,MDA concentration in the liver tissue were significantly higher than those of control group(P<0.05).The activities of SOD in 50 and 500 nmol/ml and CAT in 5,50 and 500 nmol/ml CdTe QDs groups were significantly lower than those of control group(P<0.01).Positive staining for 8-OHdG appeared in 50 and 500nmol/ml CdTe QDs groups and the apoptosis of liver cells was observed in 500nmol/ml CdTe QDs group by TUNEL technique.Conclusion It was suggested that CdTe QDs at certain doses could induce oxidative damage effects of the mice liver in the condition of this experiment.