拓扑酶抑制剂ISO-1对小鼠胚泡植入的影响

Effect of tautomerase activity inhibitor ISO-1 on implantation of the mouse embryo

目的探讨巨噬细胞移动抑制因子(MIF)拓扑酶抑制剂ISO-1对小鼠胚泡植入的影响及其作用机制。方法将150只妊娠3d小鼠随机分为5组,即低、中、高剂量组及1%二甲基亚砜(DMSO)和生理盐水(NS)两个对照组。低、中、高剂量组分别按2、6、18 mg/kg一次性腹腔注射ISO-1,对照组注射等量1%DMSO或NS;妊娠4d各组小鼠处死一半,取出子宫进行HE染色,免疫组织化学SP法检测MIF蛋白的表达,原位杂交检测MIFmRNA的表达;妊娠8d处死另半数妊娠小鼠,观察胚胎数,测量子宫脏器系数。结果与对照组比较,低、中剂量组小鼠胚胎数和子宫脏器系数差异不显著(P>0.05);高剂量组胚胎数显著提高(P<0.05),而子宫脏器系数差异不显著(P>0.05);光镜观察未发现各组妊娠小鼠子宫内膜结构的明显差异;MIF蛋白和mRNA主要表达于小鼠子宫内膜的基质细胞团,但实验组阳性细胞的吸光度值与对照组相比差异不显著(P>0.05)。结论 ISO-1可能具有促进小鼠胚泡植入的作用,且此作用具有一定的剂量依赖性;ISO-1可能通过拮抗MIF的生物学作用促进小鼠胚泡的植入。

Objective To investigate the effects of 1SO-l, a selective macrophage migration inhibitory factor （MIF） tautomerase activity inhibitor,on the blastocysts implantation in mice and its mechanism. Methods Totally 150 pregnant mice were randomly divided into five groups. Low- dose, middle-dose and high-dose groups were given ISO-1 （2 mg/kg, 6 mg/kg, 18 mg/kg, respectively） by i.p. injection on day 3 of pregnancy and the two control groups were treated with the equal volume of 1% dimethyl sulfoxide （DMSO） or saline. A half of the mice were killed on the day 4 of pregnancy, and the uteri were excised. Structures of the endometrium were observed with HE staining. The expressions of MIF protein and mRNA were studied by the immunohistochemical staining and in situ hybridization techniques, respectively. The remaining half of the mice were killed on day 8 of pregnancy to examine the number of the embryos and calculate the uterine organ coefficient. Results Compared with the controls, there were no significant differences in the number of the embryos and the uterine organ coefficient in the low-dose group and middle-dose group （P 〉 0. 05 ）. In the high-dose group, the number of the embryos increased significantly （ P 〈 0. 05 ） , but there were no significant differences in the uterine organ coefficient compared with the controls （ P 〉 0.05 ）. The histological structure of endometrium showed no significant modifications among the groups, MIF protein and mRNA were mostly expressed in the cell aggregates scattered throughout the stroma. There were no significant differences in the average absorbance of MIF protein and mRNA in all the experimental groups compared with the controls （ P 〉 0. 05 ）. Conclusion ISO-1 may promote mice blastocysts implantation in a dose-dependent manner. ISO-1 may improve blastocysts implantation in mice by antagonizing the biological function of MIF.