Zinc oxide nanoparticles induce toxic responses in human neuroblastoma SHSY5Y cells in a size-dependent manner

Abstract

Jia Liu,1 Yiyuan Kang,1 Suhan Yin,1 Bin Song,2 Limin Wei,3 Liangjiao Chen,4 Longquan Shao1 1Department of Stomatology, Nanfang Hospital, Southern Medical University, Guangzhou, 2Department of Stomatology, Guizhou Provincial People’s Hospital, Guiyang, 3Department of Pediatric Dentistry, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, 4Key Laboratory of Oral Medicine, Guangzhou Institute of Oral Disease, Stomatology Hospital of Guangzhou Medical University, Guangzhou, China Abstract: Due to the widespread applications of zinc oxide nanoparticles (ZnO NPs), the potential exposure of workers, consumers, and scientists to these particles has increased. This potential for exposure has attracted extensive attention in the science community. Many studies have examined the toxicological profile of ZnO NPs in the immune system, digestive system, however, information regarding the toxicity of ZnO NPs in the nervous system is scarce. In this study, we detected the cytotoxicity of two types of ZnO NPs of various sizes – ZnOa NPs and ZnOb NPs – and we characterized the shedding ability of zinc ions within culture medium and the cytoplasm. We found that reactive oxygen species played a crucial role in ZnO NP-induced cytotoxicity, likely because zinc ions were leached from ZnO NPs. Apoptosis and cytoskeleton changes were also toxic responses induced by the ZnO NPs, and ZnOb NPs induced more significant toxic responses than ZnOa NPs in SHSY5Y cells. In conclusion, ZnO NPs induced toxic responses in SHSY5Y cells in a size-dependent manner, which can probably be attributed to their ion-shedding ability. Keywords: zinc oxide, nanoparticles, SHSY5Y cells, reactive oxygen species, apoptosis, cell cytoskeleton

Keywords

• Zinc oxide
• nanoparticles
• SH-SY5Y cells
• reactive oxygen species
• apoptosis
• cell cytoskeleton