摘要
目的探究亚砷酸钠诱导的活性氧是否影响N~6-甲基腺苷(m~6A)水平,从RNA表观遗传学角度探讨亚砷酸钠的毒性机制。方法以亚砷酸钠作为活性氧诱导剂,以N-乙酰半胱氨酸作为活性氧清除剂,检测细胞在亚砷酸钠单独处理和亚砷酸钠联合N-乙酰半胱氨酸处理情况下皮肤细胞活性氧积累情况,同时测定m~6A及其甲基化酶的m RNA和蛋白水平的改变。结果在5、10和15μM的亚砷酸钠处理下,活性氧含量随砷浓度升高而增加;在亚砷酸钠染毒浓度为15μM时,细胞内总m~6A水平水平相比于对照组升高了1.49倍(P<0.05),m~6A甲基化酶(METTL3、METTL14和WTAP)m RNA表达水平相应升高(P<0.05),METTL14和WTAP蛋白表达水平分别为对照组的1.47倍和1.85倍(P<0.05)。N-乙酰半胱氨酸可以降低异常升高的活性氧、m~6A以及其甲基化酶水平。结论亚砷酸钠诱导的活性氧能增加人皮肤细胞m~6A的修饰水平,其机制可能与上调m~6A甲基化酶表达水平有关。
Objective The aim of this study was to explore whether reactive oxygen species(ROS) induced by sodium arsenite affect N~6-methyladenosine(m~6A) level, in order to provide a new idea for the study on toxicity induced by arsenite from the perspective of RNA epigenetics. Methods Arsenite was used to induce ROS, and N-acetylcysteine was used to eliminate ROS. ROS level, mRNA and protein levels of m~6A and its methylases(METTL3, METTL14, and WTAP) were tested in arsenite treatment group and arsenite combined with N-acetylcysteine treatment group. Results 5, 10 and 15 μM of arsenite elevated ROS level in a concentration-dependent manner. With the treatment of 15 μM arsenite, the m~6A level increased 1.49-fold compared to the control(P<0.05), the RNA levels of m~6A methylases(METTL3, METTL14 and WTAP) elevated(P<0.05), and the protein levels of METTL14 and WTAP were increased 1.47-fold and 1.85-fold compared to the control,respectively(P<0.05). N-acetylcysteine could suppress abnormal increase of m~6A and its methylases levels in HaCaT cells treated by arsenite. Conclusion ROS induced by arsenite increases m~6A level possibly via upregulation of m~6A methylases.
引文
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