3种量子点促小胶质细胞炎性反应作用比较及机制探究

Comparison and mechanism exploration of three kinds of quantum dots promoting inflammatory in microglia

目的比较CdTe量子点(quantum dots,QDs)、CdTe@ZnS QDs和Ag_(2)Se QDs促小胶质细胞炎性反应作用的差异,探究炎性反应产生的机制。方法采用小鼠源性小胶质细胞株BV2为体外模型,QDs设置1.25、2.50和5.00 nmol/L浓度梯度,分别染毒3、6、12和24 h。比色法检测细胞LDH释放,ELISA法检测胞外IL-1β水平,Western blot法检测细胞核和细胞质内P65和Ikb表达水平,流式细胞术检测胞内活性氧(ROS)水平。结果细胞分别暴露于3种QDs后,与对照组相比,LDH释放水平会随着QDs染毒时间和浓度升高。LDH升高水平:CdTe QDs>CdTe@ZnS QDs>Ag_(2)Se QDs;IL-1β释放水平也随着QDs浓度升高,IL-1β升高水平:CdTe QDs>Ag_(2)Se QDs>CdTe@ZnS QDs。暴露后,细胞质内P65和Ikb表达水平随QDs浓度升高而减少;细胞内ROS水平随QDs浓度升高,ROS升高水平:CdTe QDs>CdTe@ZnS QDs>Ag_(2)Se QDs。结论3种QDs均可引起BV2细胞的炎性反应和氧化应激,进而激活NF-κB通路。比较3种QDs的细胞毒性和促炎效应,包锌可以有效缓解含镉量子点的毒性,低毒组分的量子点毒性有很大降低。

Objective The pro-inflammatory effect and mechanismof CdTe quantum dots(QDs),CdTe@ZnS QDs and Ag_(2)Se QDs in microglia.Methods Cell line BV2 was used as the in vitro model.Three concentration groups was set as 1.25,2.50,and 5.00 nmol/L,and the exposure time was 3,6,12 and 24 h,respectively.Cellular LDH release was measured by colorimetric assay.Extracellular IL-1βlevel was measured by ELISA assay.P65 and Ikb expression in the ucleus and cytoplasm were measured by Western Blot assay.Intracellular ROS levels were measured by flow cytometry.Results Compared with control group,the level of LDH release was increased with the exposure time and concentration of three QDs,and the increase was CdTe QDs>CdTe@ZnS QDs>Ag_(2)Se QDs.The IL-1βrelease level was also increased with QDs concentration,and the increase was CdTe QDs>Ag_(2)Se QDs>CdTe@ZnS QDs.After the exposure,the expressions of cytoplasmic P65 and Ikb decreased.The intracellular ROS was increased with the exposure,and the increase was CdTe QDs>CdTe@ZnS QDs>Ag_(2)Se QDs.Conclusion All the three QDs were able to induce the inflammatory response and oxidative stress in BV2 cells,and the NF-B pathway was then activated.The cytotoxic and pro-inflammatory effects of the three QDs were compared,zinc coating can effectively alleviate the toxicity of cadmium-containing quantum dots.