Dong Daoyin, Yu Jingwen, Wu Yanqing, Fu Noah, Villela Natalia Arias, Yang Peixin
Department of Obstetrics, Gynecology & Reproductive Sciences, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
Department of Obstetrics, Gynecology & Reproductive Sciences, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
Biochem Biophys Res Commun. 2015 Nov 13;467(2):407-12. doi: 10.1016/j.bbrc.2015.09.137. Epub 2015 Sep 30.
DNA damage and DNA damage response (DDR) in neurulation stage embryos under maternal diabetes conditions are not well understood. The purpose of this study was to investigate whether maternal diabetes and high glucose in vitro induce DNA damage and DDR in the developing embryo through oxidative stress. In vivo experiments were conducted by mating superoxide dismutase 1 (SOD1) transgenic male mice with wild-type (WT) female mice with or without diabetes. Embryonic day 8.75 (E8.75) embryos were tested for the DNA damage markers, phosphorylated histone H2A.X (p-H2A.X) and DDR signaling intermediates, including phosphorylated checkpoint 1 (p-Chk1), phosphorylated checkpoint 2 (p-Chk2), and p53. Levels of the same DNA damage markers and DDR signaling intermediates were also determined in the mouse C17.2 neural stem cell line. Maternal diabetes and high glucose in vitro significantly increased the levels of p-H2A.X. Levels of p-Chk1, p-Chk2, and p53, were elevated under both maternal diabetic and high glucose conditions. SOD1 overexpression blocked maternal diabetes-induced DNA damage and DDR in vivo. Tempol, a SOD1 mimetic, diminished high glucose-induced DNA damage and DDR in vitro. In conclusion, maternal diabetes and high glucose in vitro induce DNA damage and activates DDR through oxidative stress, which may contribute to the pathogenesis of diabetes-associated embryopathy.
在母体糖尿病条件下，神经胚形成阶段胚胎中的DNA损伤和DNA损伤反应（DDR）尚未得到充分了解。本研究的目的是调查母体糖尿病和体外高糖是否通过氧化应激在发育中的胚胎中诱导DNA损伤和DDR。体内实验通过将超氧化物歧化酶1（SOD1）转基因雄性小鼠与患有或不患有糖尿病的野生型（WT）雌性小鼠交配进行。检测胚胎第8.75天（E8.75）胚胎的DNA损伤标志物、磷酸化组蛋白H2A.X（p-H2A.X）和DDR信号中间体，包括磷酸化检查点1（p-Chk1）、磷酸化检查点2（p-Chk2）和p53。还在小鼠C17.2神经干细胞系中测定了相同DNA损伤标志物和DDR信号中间体的水平。母体糖尿病和体外高糖显著增加了p-H2A.X的水平。在母体糖尿病和高糖条件下，p-Chk1、p-Chk2和p53的水平均升高。SOD1过表达在体内阻断了母体糖尿病诱导的DNA损伤和DDR。Tempol，一种SOD1模拟物，在体外减少了高糖诱导的DNA损伤和DDR。总之，母体糖尿病和体外高糖通过氧化应激诱导DNA损伤并激活DDR，这可能有助于糖尿病相关胚胎病的发病机制。
