沙尘与非沙尘PM_(2.5)对人肺成纤维细胞存活率及细胞间通讯的影响

目的探讨沙尘与非沙尘PM2.5对人肺成纤维细胞存活率及细胞间通讯的影响。方法使用沙尘与非沙尘PM2.5的全颗粒、无机提取物和有机提取物,按它们在PM2.5中的质量比例,确定各自的染毒浓度。受试物处理细胞24小时后,采用MTT法测定细胞的存活率,并用划痕染料标记示踪法测定细胞缝隙连接通讯(GJIC)水平。结果在按上述确定的染毒浓度范围,沙尘和非沙尘全颗粒、沙尘无机提取物表现出明显的细胞毒性,有剂量-反应关系,且沙尘全颗粒的毒性最大。细胞划痕实验结果显示,沙尘和非沙尘PM2.5的全颗粒及其提取物均可抑制细胞间荧光扩散,抑制作用随剂量增高而增强,且有机提取物的抑制作用最强,其次是全颗粒,再次为无机提取物。结论颗粒物的来源和成分是影响其毒性的重要因素;沙尘与非沙尘PM2.5都能抑制细胞间通讯,GJIC可能为颗粒物的毒性机制之一。

Effect of PM2.5 collected during the dust and non-dust periods on the viability and gap junctional intercellular communication in human lung fibroblasts

Objective To investigate the effects of PM_ 2.5 collected during the dust and non-dust periods on the viability and gap junctional intercellular communication (GJIC) in human lung fibroblasts. Methods Human lung fibroblasts were treated with PM_ 2.5 suspension and its organic and inorganic extracts at various concentrations for 24 h. The cellular viability was measured with MTT methods, and the GJIC between human lung fibroblasts was detected by the scrape loading dye transfer assay. Results PM_ 2.5 suspension from both sources and the inorganic extracts of dust PM_ 2.5 significantly decreased the viability of human lung fibroblast in a dose-dependent manner. Compared with other preparations, the dust PM_ 2.5 suspension had the highest effect. Gap junctional intercellular communication between human lung fibroblasts was significantly inhibited by the different composition of PM_ 2.5 from both sources in a dose-dependent manner. The inhibitory effects on GJIC were in the order of organic extract of PM_ 2.5 > suspension > inorganic extract. Conclusion Composition and source of PM_ 2.5 are important factors which influnce the toxic effects on cells. The composition of PM_ 2.5 from both sources can inhibit GJIC, suggesting decreasing GJIC may be related to the biological mechanisms of toxicity caused by PM_ 2.5.