Biological Action Mechanism of Graphene Oxide and Artificial Regulation of Biosafety

State Key Laboratory of Environmental Chemistry and Ecotoxicology, Chinese Academy of Sciences Research Center Liu Sijin's group has made new advances in the role of non-coding RNA miR-214 in arsenic-induced apoptotic cell death. Research findings have recently been published in the Journal of Free Radical Research. Free Radical Biology & Medicine (Free Radic Biol Med, 2016, 92:39-49); At the same time, progress has been made in the toxicity and biosafety control of graphene oxide (GO), and relevant research results have recently been published online at the American Chemical Society. The magazine ACS Nano (ACS Nano, 2016, DOI: 10.1021/acsnano.6b00539).

Arsenide is an environmental pollutant that is a serious hazard to human health, but its toxicological effects, especially the mechanism of toxicity of erythroid cells, remain unclear. The team found that the expression level of miR-214 was significantly down-regulated under the oxidative stress of erythroid cells (especially stimulated by arsenide). The results of overexpression and knockdown experiments showed that down-regulation of miR-214 antagonized arsenide-induced cell death effects. Further molecular studies revealed that arsenic induced oxidative stress resulted in a significant increase in the cellular stress protein Nrf2, and its binding to the miR-214 promoter significantly increased after entry into the nuclei, ultimately inhibiting the transcription of miR-214. expression. At the same time, it was found that the cell stress protein ATF4 and the key histone modification molecule EZH2 are direct downstream target genes of miR-214. Down-regulation of miR-214 expression stimulated by arsenic stimulated the protein levels of ATF4 and EZH2, and further antagonized arsenic induction. The cell death. This study has important implications for revealing the erythroid cytotoxicity of arsenic and the scientific value of miR-214 in environmental health research.

The team also found that the surface physicochemical properties of GO significantly affect its biological effects and toxicity. In the biological medium, the surface of the original GO adsorbs a large number of protein molecules, and some proteins with important biological functions (such as immunoglobulins) mediate the binding of the GO nanoparticles and the macrophage membrane, resulting in the original GO nanoparticles It is easily recognized, adhered and engulfed by macrophages. At the molecular level, it was confirmed that GO affects the levels of membrane structural and functionally related proteins, leading to abnormalities in cell membrane structure and function (such as cell membrane permeability, fluidity, membrane potential, and ion channels, etc.), which is also a cytotoxicity of GO. One of the mechanisms. At the same time, by controlling the surface physicochemical properties of GO, four different surface properties of GO (GO-NH2, GO-PEG, GO-PAM, GO-PAA) were prepared, and the in vitro and in vivo toxicity of these GO derivatives were studied in-depth. effect. The results show that PEG- and PAA-modification can greatly reduce the role of GO and cell membrane and injury, and relieve GO-induced toxicity in vivo. This research work has important scientific value for revealing the toxicity of graphene oxide and environmental health risks.

These researches have been supported by the national "973" project, the pilot project of the Chinese Academy of Sciences, and the project of the Natural Science Foundation of the Committee of the Foundation.

Wood Plastic Screwdriver

Wood plastic screwdriver,wood screwdriver,good quality screwdriver,non-slip screwdriver

henan horn tools co.,ltd. , https://www.horntoolsltd.com