5-Ethynyl-2'-deoxyuridine

5-ethynyl-2′-deoxyuridine (EdU), as a thymidine analoghas, a terminal alkyne group replacing a methyl group at the 5 position of the pyrimidine ring and can be readily incorporated into DNA during synthesis[1]. EdU is a inhibitor of the cell growth of human breast cancer cells (MCF-7 and MDA-MP-231) with the IC₅₀ of 0.4 μM for MCF-7 cells and 4.4 μM for MDA-MB-231 cells^[2].

In vitro, 10 μMEdU induced gamma-H2AX foci for 51D1 and KO40 in CHO cells for DNA damage responses^[3]. In vitro experiment it shown that A549 cells were treated with 20 μM EdU for 6 h increased the level of expression of γH2AX and ATM-S1981P by 88% and 116%, respectively^[4].

In vivo efficacy test it shown that femalJKe mice were administrated 10, 20, 50, 100 or 200 mg/kg EdU intraperitoneally, there is an increase in the number of EdU positive cells in the DG slightlyin a dose-dependent manner^[5]. In vivo, few EdU-positive cells were observed in Wistar and GK rats at a dose of 5 mg/kg and 25 mg/kg EdU intraperitoneally. Prominent EdU-positive cells were observed in Wistar and GK rats at a dose of 100 mg/kg and 200 mg/kg, respectively^[6]. In vivo, use of 5-Ethynyl-2'-deoxyuridine (EdU) incorporation to in vivo monitor T lymphocyte proliferation by flow cytometry with an adoptive transfer model. The result shown that the percentage of EdU-positive cells increased in a dose-dependent manner, and the saturated dose of EdU was 20mg/kg. Intraperitoneal and intravenous injection had no differences in lymphocyte proliferation detection with EdU in vivo^[7].

References:

[1] Kaiser CL, et al. 5-Ethynyl-2'-deoxyuridine labeling detects proliferating cells in the regenerating avian cochlea. Laryngoscope. 2009 Sep;119(9):1770-5.

[2] Meneni S, et al. (2007) 5-Alkynyl-2′-deoxyuridines: chromatography-free synthesis and cytotoxicity evaluation against human breast cancer cells. Bioorg Med Chem 15: 3082–3088.

[3] Haskins JS, et al. Evaluating the Genotoxic and Cytotoxic Effects of Thymidine Analogs, 5-Ethynyl-2'-Deoxyuridine and 5-Bromo-2'-Deoxyurdine to Mammalian Cells. Int J Mol Sci. 2020 Sep 10;21(18):6631.

[4] Zhao H, et al. DNA damage signaling, impairment of cell cycle progression, and apoptosis triggered by 5-ethynyl-2'-deoxyuridine incorporated into DNA. Cytometry A. 2013 Nov;83(11):979-88.

[5] Zeng C, et al. Evaluation of 5-ethynyl-2'-deoxyuridine staining as a sensitive and reliable method for studying cell proliferation in the adult nervous system. Brain Res. 2010 Mar 10;1319:21-32.

[6] Guo J, Li D, et al. Detecting DNA synthesis of neointimal formation after catheter balloon injury in GK and in Wistar rats: using 5-ethynyl-2'-deoxyuridine. Cardiovasc Diabetol. 2012 Dec 13;11:150.

[7] Sun X, Zhang C, et al. Flow cytometric analysis of T lymphocyte proliferation in vivo by EdU incorporation. Int Immunopharmacol. 2016 Dec;41:56-65.

5-乙炔基-2′-脱氧尿苷（EdU）,作为胸苷类似物,是取代嘧啶环5位甲基的末端炔基,在合成过程中可以很容易地结合到DNA中^[1]。EdU是人类乳腺癌症细胞（MCF-7和MDA-MP-231）的细胞生长抑制剂,MCF-7细胞的IC₅₀为0.4 μM,MDA-MB-231细胞为4.4μM^[2]。

在体外,10 μM EdU诱导CHO细胞中51D1和KO40的γ-H2AX焦点产生DNA损伤反应^[3]。体外实验表明,用20 μM EdU处理A549细胞6小时,γH2AX和ATM-S1981P的表达水平分别提高了88%和116%^[4]。

体内疗效测试表明,雌性JKe小鼠腹膜内给予10、20、50、100或200 mg/kg EdU,DG中EdU阳性细胞的数量略有增加,呈剂量依赖性^[5]。在体内,在Wistar和GK大鼠中观察到腹膜内剂量为5 mg/kg和25 mg/kg EdU的EdU阳性细胞很少。在Wistar和GK大鼠中分别观察到剂量为100 mg/kg和200 mg/kg的显著EdU阳性细胞^[6]。在体内,使用5-乙炔基-2'-脱氧尿苷（EdU）掺入通过过继转移模型的流式细胞术在体内监测T淋巴细胞增殖。结果表明,EdU阳性细胞的百分比呈剂量依赖性增加,EdU的饱和剂量为20 mg/kg。腹膜内注射和静脉注射在体内用EdU检测淋巴细胞增殖方面没有差异^[7]。