Jiang Xuefeng, Lu Chunjiao, Tang Mingjie, Yang Zhongbo, Jia Weijiao, Ma Yanbo, Jia Panpan, Pei Desheng, Wang Huabin
Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
ACS Omega. 2018 Jun 30;3(6):6770-6778. doi: 10.1021/acsomega.8b00608. Epub 2018 Jun 21.
Human embryonic kidney 293T cells (HEK293T cells) before and after treatment with silver nanoparticles (AgNPs) were measured using advanced atomic force microscopy (AFM) force measurement technique, and the biomechanical property of cells was analyzed using a theoretical model. The biomechanical results showed that the factor of viscosity of untreated HEK293T cells reduced from 0.65 to 0.40 for cells exposure to 40 μg/mL of AgNPs. Comet assay indicated that significant DNA damage occurred in the treated cells, measured as tail DNA% and tail moment. Furthermore, gene expression analysis showed that for the cells treated with 40 μg/mL of AgNPs, the antiapoptosis genes and were, respectively, downregulated to 0.65- and 0.66-fold of control, and that the proapoptosis gene was upregulated to 1.55-fold of control, which indicates that apoptosis occurred in cells exposed to AgNPs. Interestingly, excellent negative correlations were found between the factor of viscosity and tail DNA%, and tail moment, which suggest that the biomechanical property can be correlated with genotoxicity of nanoparticles on the cells. Based on the above results, we conclude that (1) AgNPs can lead to biomechanical changes in HEK293T cells, concomitantly with biological changes including cell viability, DNA damage, and cell apoptosis; (2) the factor of viscosity can be exploited as a promising label-free biomechanical marker to assess the nanotoxicity of nanoparticles on the cells; and (3) the combination of AFM-based mechanical technique with conventional biological methods can provide more comprehensive understanding of the nanotoxicity of nanoparticles than merely by using the biological techniques.
使用先进的原子力显微镜（AFM）力测量技术测量了银纳米颗粒（AgNPs）处理前后的人胚肾293T细胞（HEK293T细胞），并使用理论模型分析了细胞的生物力学特性。生物力学结果表明，对于暴露于40μg/mL AgNPs的细胞，未处理的HEK293T细胞的粘度系数从0.65降至0.40。彗星试验表明，处理后的细胞发生了显著的DNA损伤，以尾DNA%和尾矩来衡量。此外，基因表达分析表明，对于用40μg/mL AgNPs处理的细胞，抗凋亡基因和分别下调至对照的0.65倍和0.66倍，而促凋亡基因上调至对照的1.55倍，这表明暴露于AgNPs的细胞发生了凋亡。有趣的是，发现粘度系数与尾DNA%和尾矩之间存在极好的负相关，这表明生物力学特性可能与纳米颗粒对细胞的遗传毒性相关。基于上述结果，我们得出以下结论：（1）AgNPs可导致HEK293T细胞的生物力学变化，同时伴随着包括细胞活力、DNA损伤和细胞凋亡在内的生物学变化；（2）粘度系数可作为一种有前景的无标记生物力学标志物，用于评估纳米颗粒对细胞的纳米毒性；（3）基于AFM的机械技术与传统生物学方法相结合，比仅使用生物学技术能更全面地了解纳米颗粒的纳米毒性。
