kisspeptin调控Notch1/Akt/Foxo1通路参与复发性流产患者子宫内膜蜕膜化

Notch1/Akt/Foxo1 Pathway Regulated by Kisspeptin Is Involved in Endometrial Decidualization in Patients With Recurrent Spontaneous Abortion

目的 kisspeptin是一种肿瘤抑制因子,由KISS1基因编码。Notch1/Akt/Foxo1是调节细胞增殖、分化的重要信号通路。本研究探讨kisspeptin通过Notch1/Akt/Foxo1信号通路调控子宫内膜蜕膜化在复发性流产(RSA)中的作用机制。方法 纳入2020年6月–2020年12月苏州大学附属第二医院生殖中心门诊收治的RSA患者45例及同期计划生育门诊择期人工流产女性50例,Western blot、RT-qPCR检测蜕膜组织中kisspeptin(及其基因KISS1)、蜕膜化标志物胰岛素样生长因子结合蛋白1(insulin-like growth factor binding protein 1, IGFBP1)、Notch1、Akt、Foxo1表达水平。使用siRNA干扰KISS1或添加kisspeptin10(kisspeptin的活性片段)处理永生化子宫内膜基质细胞(hESC)后,命名为siKP组或KP10组,并设转染空白siRNA的hESC为对照组,CCK8检测增殖情况。对3组hESC进行体外诱导蜕膜化,免疫荧光检测siKP组和KP10组细胞Notch1表达及蜕膜化形态差异,RT-qPCR和Western blot检测3组细胞IGFBP1、Notch1、Akt、Foxo1的表达。hESC添加Notch1、Akt、Foxo1对应抑制剂后诱导蜕膜化(以仅诱导蜕膜化、未添加抑制剂的hESC为正常对照组),检测4组细胞上述蛋白和基因的表达。建立正常妊娠(CBA/J×BALB/c)和复发性流产(CBA/J×DBA/2)小鼠模型,即NP模型和RSA模型,实验组分别给予kisspeptin10和kisspeptin234(阻滞剂)隔日1次腹腔注射(RSA-KP10组和NP-KP234组),对照组给予生理盐水隔日1次腹腔注射(RSA-NS组和NP-NS组),共4组,每组6只,取孕9.5 d的子宫组织,观察胚胎吸收的情况,检测上述蛋白和基因的表达。结果 与正常妊娠(NP)女性相比,RSA患者kisspeptin、IGFBP1、Notch1、Akt、Foxo1的蛋白及其基因表均降低(P<0.01或P<0.05)。hESC添加kisspeptin10后蜕膜化能力增强,Notch1、Akt、Foxo1的蛋白及基因表达增加,干扰KISS1后表达降低;免疫荧光见增殖状态的hESC呈细长形,蜕膜化后细胞变圆、变大,Notch1表达增加,添加kisspeptin10后蜕膜化程度增高,干扰KISS1后减弱;分别用Notch1、Akt、Foxo1抑制剂处理hESC,发现三者按Notch1/Akt/Foxo1的顺序依次调控(P<0.05)。与注射生理盐水组相比,正常妊娠小鼠注射kisspeptin234后吸收胎增多(P<0.001),IGFBP1、Notch1、Akt、Foxo1的蛋白及基因表达下降(P<0.05);复发流产小鼠注射kisspeptin10后吸收胎减少(P<0.001),上述蛋白及基因表达升高(P<0.05)。结论 kisspeptin可能通过Notch1/Akt/Foxo1信号通路调控子宫内膜蜕膜化,其表达下调导致蜕膜化不良,可能是导致RSA发病的原因之一。

Objective Kisspeptin,a protein encoded by the KISS1 gene,functions as an essential factor in suppressing tumor growth.The intricate orchestration of cellular processes such as proliferation and differentiation is governed by the Notch1/Akt/Foxo1 signaling pathway,which assumes a central role in maintaining cellular homeostasis.In the specific context of this investigation,the focal point lies in a meticulous exploration of the intricate mechanisms underlying the regulatory effect of kisspeptin on the process of endometrial decidualization.This investigation delves into the interplay between kisspeptin and the Notch1/Akt/Foxo1 signaling pathway,aiming to elucidate its significance in the pathophysiology of recurrent spontaneous abortion(RSA).Methods We enrolled a cohort comprising 45 individuals diagnosed with RSA,who were admitted to the outpatient clinic of the Reproductive Center at the Second Affiliated Hospital of Soochow University between June 2020 and December 2020.On the other hand,an additional group of 50 women undergoing elective abortion at the outpatient clinic of the Family Planning Department during the same timeframe was also included.To comprehensively assess the molecular landscape,Western blot and RT-qPCR were performed to analyze the expression levels of kisspeptin(and its gene KISS1),IGFBP1(an established marker of decidualization),Notch1,Akt,and Foxo1 within the decidua.Human endometrial stromal cells(hESC)were given targeted interventions,including treatment with siRNA to disrupt KISS1 or exposure to kisspeptin10(the bioactive fragment of kisspeptin),and were subsequently designated as the siKP group or the KP10 group,respectively.A control group comprised hESC was transfected with blank siRNA,and cell proliferation was meticulously evaluated with CCK8 assay.Following in vitro induction for decidualization across the three experimental groups,immunofluorescence assay was performed to identify differences in Notch1 expression and decidualization morphology between the siKP and the KP10 groups.Furthermore,RT-qPCR and Western blot were performed to gauge the expression levels of IGFBP1,Notch1,Akt,and Foxo1 across the three cell groups.Subsequently,decidualization was induced in hESC by adding inhibitors targeting Notch1,Akt,and Foxo1.The expression profiles of the aforementioned proteins and genes in the four groups were then examined,with hESC induced for decidualization without adding inhibitors serving as the normal control group.To establish murine models of normal pregnancy(NP)and RSA,CBA/J×BALB/c and CBA/J×DBA/2 mice were used.The mice were respectively labeled as the NP model and RSA model.The experimental groups received intraperitoneal injections of kisspeptin10 and kisspeptin234(acting as a blocker)and were designated as RSA-KP10 and NP-KP234 groups.On the other hand,the control groups received intraperitoneal injections of normal saline(NS)and were referred to as RSA-NS and NP-NS groups.Each group comprised 6 mice,and uterine tissues from embryos at 9.5 days of gestation were meticulously collected for observation of embryo absorption and examination of the expression of the aforementioned proteins and genes.Results The analysis revealed that the expression levels of kisspeptin,IGFBP1,Notch1,Akt,and Foxo1 were significantly lower in patients diagnosed with RSA compared to those in women with NP(P<0.01 for kisspeptin and P<0.05 for IGFBP1,Notch1,Akt,and Foxo1).After the introduction of kisspeptin10 to hESC,there was an observed enhancement in decidualization capability.Subsequently,the expression levels of Notch1,Akt,and Foxo1 showed an increase,but they decreased after interference with KISS1.Through immunofluorescence analysis,it was observed that proliferative hESC displayed a slender morphology,but they transitioned to a rounder and larger morphology post-decidualization.Concurrently,the expression of Notch1 increased,suggesting enhanced decidualization upon the administration of kisspeptin10,but the expression decreased after interference with KISS1.Further experimentation involved treating hESC with inhibitors specific to Notch1,Akt,and Foxo1 separately,revealing a regulatory sequence of Notch1/Akt/Foxo1(P<0.05).In comparison to the NS group,NP mice administered with kisspeptin234 exhibited increased fetal absorption rates(P<0.001)and decreased expression of IGFBP1,Notch1,Akt,and Foxo1(P<0.05).Conversely,RSA mice administered with kisspeptin10 demonstrated decreased fetal absorption rates(P<0.001)and increased expression levels of the aforementioned molecules(P<0.05).Conclusion It is suggested that kisspeptin might exert its regulatory influence on the process of decidualization through the modulation of the Notch1/Akt/Foxo1 signaling cascade.A down-regulation of the expression levels of kisspeptin could result in suboptimal decidualization,which in turn might contribute to the development or progression of RSA.