IGF-1及其信号转导在电针改善COH小鼠胚胎着床中的作用研究

Embryo implantation failure was the critical reason which severely restricted the clinical pregnancy in vitro fertilization-embryo transplantation,insulin-like growth factor-1 was a important factor in adjusting embryo impantation,accompanying with acupuncture can increase the pregnancy rate, but the mechanism was not clear. On the basis of previously research,our study team prepose "electroacupuncture may improve mice embryo implantation after controlled ovarian hyperstimulation through regulating insulin-like growth factor-1 and its signal transduction" .In the current study, we prepared the model rice by controlled ovarian hyperstimulation, and observed the pregnant rate through electroacupuncture therapy at GuanYuan, ZhongJi and SanYinJiao piont on the day of down regulating、Gonadotropin start、HCG injection and embryo transplantation respectively, to determine the best time of acupuncture therapy; moreover,in order to explore the mechanism of electroacupuncture regulating IGF-1 and its signal transduction to improve embryo implantation, we increased or decreased the expression of insulin-like growth factor-1 by in vivo uteri gene transfection, and observed the relationship of electroacupuncture with the expression of insulin-like growth factor-1 and its critical molecular on signal transduction through RT-PCR and Western blot methods. This study will significantly benefit the acupuncture clinic, and it's very meaningful to clarify the mechanism of electroacupuncture improving embryo implantation, and this research will establish the substantial foundation for study on embryo implantation failure.

胚胎着床障碍是制约体外受精-胚胎移植临床妊娠的关键原因，胰岛素样生长因子-1（IGF-1）是调节胚胎着床的重要因子，结合针刺可提高妊娠率，但作用机制和最佳治疗时间尚不明确。本课题组在已有的工作基础上，提出"电针通过调控IGF-1及其信号转导来改善胚胎着床"的假说，采用控制性超排卵长方案制备模型小鼠，进行体外胚胎培养和种植，在降调节日、Gn启动日、HCG注射日和胚胎种植日取"关元"、"中极"、"三阴交"行电针治疗，观察小鼠妊娠率，明确电针治疗介入的最佳时间点；运用宫腔内基因转染技术上调和下调IGF-1的表达，并进行电针干预，采用RT-PCR、Western blot等方法检测子宫内膜IGF-1及其信号转导中关键分子的表达，阐明电针调节IGF-1及其信号转导改善胚胎着床的作用机制。研究结果对针灸临床和阐明针灸改善胚胎着床的作用机制具有重要意义，为胚胎着床障碍的研究奠定基础。

体外受精-胚胎移植广泛用于不孕症的治疗，但临床妊娠率只有20% ~35%。大量临床及动物实验显示针刺对妊娠结局有促进作用。基于IGF-1是调节胚胎着床的重要因子，我们假定：针刺通过调整IGF-1及其信号转导改善胚胎着床。本项目采用控制性超排卵长方案制备模型小鼠，进行体外胚胎培养和种植，运用基因转染、分子生物学、形态学等技术，观察超排卵后子宫内膜IGF-1及其信号转导的变化及电针“关元”、“中极”、“三阴交”穴的影响。结果显示：1.超排卵后，IGF-1显著下降，妊娠率、平均着床位点数减少；2. HCG注射日行电针治疗可显著提高临床妊娠率，增加子宫内膜厚度、腺体直径、周长及面积；3.电针能提高子宫内膜IGF-1及其 mRNA表达水平；4.下调IGF-1表达可部分阻断电针效应；5. 电针可增加子宫内膜IGF-1R mRNA、IGF-1R、p-IGF-1R、p-Akt、p-ERK1/2表达水平；6.IGF-1受体拮抗剂可部分阻断电针对IGF-1信号转导通路的调节效应；7.AKT阻断剂或ERK1/2阻断剂对针刺效应的影响较小。上述证据提示，IVF-ET临床妊娠率低与子宫内膜IGF-1表达减少有关；HCG注射日为电针治疗介入的最佳时间点；针刺可能通过调节IGF-1及其信号转导改善胚胎着床。本研究为从分子水平阐明针刺改善胚胎着床的作用机制，为胚胎着床障碍的基础研究和IVF-ET结合针刺治疗的临床应用提供重要的理论依据。