International Journal of Nanomedicine (Nov 2018)
A comparative study of toxicity of TiO2, ZnO, and Ag nanoparticles to human aortic smooth-muscle cells
Abstract
Maolin Wang,1,* Qianyu Yang,1,* Jimin Long,1 Yanghuai Ding,1 Xiaoqing Zou,1 Guochao Liao,2 Yi Cao1 1Key Laboratory of Environment-Friendly Chemistry and Application of Ministry of Education, Laboratory of Biochemistry, College of Chemistry, Xiangtan University, Xiangtan, Hunan 411105, People’s Republic of China; 2International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, People’s Republic of China *These authors contributed equally to this work Purpose: To evaluate the adverse vascular effects of nanoparticles (NPs) in vitro, extensive studies have investigated the toxicity of NPs on endothelial cells, but the knowledge of potential toxicity on human smooth-muscle cells (SMCs) is currently limited.Methods: This study compared the toxicity of TiO2, ZnO, and Ag NPs to human aortic SMCs. Results: Only ZnO NPs significantly induced cytotoxicity, accompanied by increased intracellular reactive oxygen species, Zn ions, and endoplasmic reticulum stress biomarkers (DDIT3 expression and p-Chop proteins). All the NPs significantly promoted the release of soluble VCAM1 and soluble sICAM1, but not IL6, which suggested that metal-based NPs might promote inflammatory responses. Furthermore, KLF4 expression (a transcription factor for SMC-phenotype switch) was significantly induced by TiO2 NPs and modestly by ZnO NPs, but the expression of CD68 remained unaltered.Conclusion: Our data indicated that ZnO NPs were more cytotoxic to human aortic SMCs than TiO2 and Ag NPs at the same mass concentrations, which might have been associated with intracellular reactive oxygen species, Zn ions, and endoplasmic reticulum stress. Keywords: metal-based nanoparticles, NPs, human aortic smooth-muscle cells, HASMCs, cytotoxicity, inflammation, endoplasmic reticulum stress, ER stress
