PMX诱导神经管畸形及其对神经上皮细胞增殖和凋亡的影响

Effect of PMX on the development of neural tube defects and neuroepithelial cell proliferation and apoptosis

目的:用培美曲塞(pemetrexed,PMX)建立叶酸缺乏的神经管畸形(neural tube defect,NTD)动物模型,并探讨其对神经上皮细胞增殖和凋亡的影响。方法:应用不同剂量PMX(5、10、15、17.5、20和30 mg/kg)对C57BL/6孕鼠进行干预,筛选最佳造模剂量。采用磷酸化组蛋白H3(pH3免疫组化的方法以及TUNEL方法)观察胎鼠神经上皮增殖和凋亡情况。结果:随着PMX剂量的增加,小鼠胚胎的吸收胎和畸形率逐渐增加,其中17.5mg/kg体重组的NTD的发生率最高(30.6%),被筛选为最佳造模剂量。pH3免疫组化和TUNEL结果显示,与正常对照组相比,NTD小鼠胚胎神经上皮细胞增殖减少(P<0.05),凋亡增加(P<0.05)。结论:PMX能诱导NTD的发生,其机制可能是因为PMX阻断了叶酸代谢通路并导致神经上皮细胞的增殖抑制和过度凋亡。

Objective： To establish neural tube defect（NTD） animal model by pemetrexed（PMX） and explore the effects of PMX on neuroepithelial cell proliferation and apoptosis.Methods： To select an optimal dose,C57BL/6 pregnant mice were injected intraperitoneally with different doses of PMX（5,10,15,17.5,20,and 30 mg/kg body weight）.TUNEL and immunohistochemisty method for phosphorylated histone H3（pH3） were used to detect neuroepithelial cell proliferation and apoptosis of NTD embryos.Results： With the increasing of PMX doses,the incidence of absorbed embryos and malformations increased and the 17.5 mg/kg group was selected to be optimal with highest rate of NTD（30.6%）.The results of pH3 immunohistochemisty and TUNEL showed that neuroepithelial cell proliferation was decreased and cellular apoptosis was increased in NTD embryos compared with normal embryos.Conclusion： NTD embryos were induced by PMX,the mechanism of which might be PMX inhibited folate metabolism pathway and led to decreased cellular proliferation and excessive cellular apoptosis.