Cytotoxicity and autophagy induction by graphene quantum dots with different functional groups

作     者：Yichun Xie Bin Wan Yu Yang Xuejing Cui Yan Xin Liang-Hong Guo 

作者机构：State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety National Center for Nanoscience and Technology of China Institute of Environment and Health Jianghan University 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2019年第31卷第3期

页      面：198-209页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 09[农学] 0903[农学-农业资源与环境] 0703[理学-化学] 070301[理学-无机化学] 0713[理学-生态学] 

基　　金：supported by the National Natural Science Foundation of China(Nos.21477146,21577163) the National Key Research and Development Program of China(No.2017YFF0211203-3) the Key Research Program of Frontier Sciences,CAS(No.QYZDJ-SSW-DQC020-02) the Chinese Academy of Sciences(No.XDB14040101) 

主　　题：Graphene quantum dots Cytotoxicity Autophagy Surface functional group 

摘      要：Graphene quantum dots(GQDs) possess great potential in various applications due to their superior physicochemical properties and wide array of available surface ***, the toxicity of GQDs has not been systematically assessed, thus hindered their further development; especially, the risk of surface modifications of GQDs is largely unknown. In this study, we employed a lung carcinoma A549 cells as the model to investigate the cytotoxicity and autophagy induction of three types GQDs, including cGQDs(COOH-GQDs), hGQDs(OH-GQDs), and aGQDs(NH_2-GQDs). The results showed hGQDs was the most toxic, as significant cell death was induced at the concentration of 100 μg/mL,determining by WST-1 assay as well as Annexin-V-FITC/PI apoptosis analysis, whereas cGQDs and aGQDs were non-cytotoxic within the measured concentration. Autophagy detection was performed by TEM examination, LC3 fluorescence tracking, and Westernblot. Both aGQDs and hGQDs induced cellular autophagy to various degrees except for cGQDs. Further analysis on autophagy pathways indicated all GQDs significantly activated p-p38 MAPK; p-ERK1/2 was inhibited by aGQDs and hGQDs but activated by c GQDs. p-JNK was inhibited by aGQDs and c GQDs, while activated by hGQDs. Simultaneously, Akt was activated by hGQDs but inhibited by aGQDs. Inhibition of autophagy by 3-MA significantly increased the cytotoxicity of GQDs, suggesting that autophagy played a protective role against the toxicity of GQDs. In conclusion, c GQDs showed excellent biocompatibility and may be considered for biological applications. Autophagy induction may be included in the health risk assessment of GQDs as it reflects the stress status which may eventually lead to diseases.