FOXO3a转录因子参与调控新生大鼠卵母细胞凋亡的实验研究

目的:探讨新生大鼠卵巢卵母细胞的凋亡是否与FOXO3a(forkhead box group O)转录因子在细胞核内高表达有关。方法:取新生1d、2d、3d、4d雌性SD大鼠卵巢,用免疫组织化学方法检测FOXO3a与其靶分子促凋亡蛋白BIM的表达变化;TUNEL化学染色观察新生大鼠卵巢中卵母细胞凋亡状况;再用免疫组织荧光联合TUNEL荧光检测技术观察FOXO3a和其靶分子BIM表达水平与卵母细胞凋亡的关系。结果:免疫组织化学结果显示,FOXO3a在一些卵母细胞巢内和原始卵泡的卵母细胞核内高表达,其阳性率在出生后1-2d较高,随后逐渐下降。与FOXO3a相似,BIM也是在一些卵母细胞巢内和原始卵泡的卵母细胞中高表达,阳性率变化规律也与FOXO3a一致。凋亡细胞主要见于卵母细胞巢内和原始卵泡的卵母细胞中,其凋亡率变化与FOXO3a阳性率变化一致。免疫组织荧光联合TUNEL荧光检测结果表明,FOXO3a(核内)与BIM高表达的卵母细胞正是凋亡的卵母细胞。结论:FOXO3a转录因子参与新生大鼠卵巢中卵母细胞巢内卵母细胞和原始卵泡卵母细胞的凋亡调控。     

新生鼠卵巢FOXO3a表达水平与卵母细胞凋亡的相关性初步研究

目的:探讨新生大鼠卵巢中FOXO3a(forkhead box groupO)转录因子表达水平与卵母细胞凋亡的相关性。方法:取出生后2d、3d、8d、15d龄大鼠的卵巢,用免疫组化方法观察FOXO3a、caspase-3在卵巢组织中的定位及表达水平,且用TUNEL技术检测卵巢内卵母细胞的凋亡变化。结果:FOXO3a在新生大鼠部分卵母细胞巢内的卵母细胞核内高表达,而在卵泡发育启动后,FOXO3a则从卵母细胞的核内逐渐转移至胞浆。而在次级和成熟卵泡的卵母细胞内,FOXO3a仅出现在胞浆内。≤8d龄大鼠卵巢的部分卵母细胞核内或胞核、胞浆内可检测到caspase-3表达,2d、3d龄大鼠部分卵母细胞核内高表达。TUNEL染色与caspase-3结果相似,2d龄大鼠卵巢的卵母细胞阳性率最高。结论:生后2d大鼠卵巢的卵母细胞存在一个凋亡高峰期;在原始卵泡形成前,FOXO3a在部分卵母细胞核内高表达,并与卵母细胞的凋亡率呈一致性。     

细胞外信号调节激酶信号转导通路活化在新生大鼠缺氧缺血性脑损伤中的作用

目的 观察细胞外信号调节激酶(extracellular-signal regulated kinase,ERK)在新生大鼠缺氧缺血性脑损伤中的作用.方法 Wistar大鼠随机分为假手术组、缺氧缺血组和PD98059(ERK抑制剂)组,通过结扎右侧颈总动脉,恢复2 h后,吸入含8%氧气的氧氮混合气体2 h的方法 建立新生大鼠缺氧缺血性脑损伤模型,PD98059组结扎右侧颈总动脉前10 min股静脉注射PD980592 mg/kg.各组新生大鼠于模型制作后6 h剥离结扎侧海马及皮层脑组织,分别测定脑组织丙二醛(malondialdehyde,MDA)含量、超氧化物歧化酶(superoxide dismutase,SOD)活性和细胞凋亡水平.Western印迹法检测ERK1和ERK2,Bcl-2和Bax蛋白的表达.组间差异比较采用方差分析及q检验.结果 缺氧缺血组细胞凋亡率明显高于假手术组[(18.80±1.37)%和(3.53±0.34)%](q=6.06,P＜0.01),PD98059组细胞凋亡率[(15.53±0.64)%]低于缺氧缺血组(q=3.87,P＜0.01).缺氧缺血组MDA含量为(342.9±10.8)μmol/L,明显高于假手术组[(181.5±17.0)μmol/L](q=6.35,P＜0.01)和PD98059组[(252.0±17.1)μmol/L](q=5.28,P＜0.01),而SOD活性[(34.8±4.3)U/ml]明显低于假手术组[(63.4±4.3)U/ml](q=4.99,P＜0.01)和PD98059组[(51.5±3.8)U/ml](q=4.17,P＜0.01).3组总ERK1和ERK2蛋白表达差异无统计学意义.缺氧缺血组磷酸化ERK1和磷酸化ERK2蛋白表达明显高于假手术组(q分别=3.82和4.08,P均＜0.01)和PD98059组(q分别=4.79和5.12,P均＜0.01).缺氧缺血后Bcl-2和Bax蛋白表达明显高于假手术组(q分别=3.55和3.42,P均＜0.01);PD98059组较缺氧缺血组抗凋亡蛋白Bcl-2表达增加,促凋亡蛋白Bax表达降低(q分别=3.71和5.86,P均＜0.01).结论 ERK激活通过调节凋亡蛋白表达参与了新生大鼠缺氧缺血性脑损伤的发生.

Abstract：

Objective To investigate the effects of extracellular-signal regulated kinase (ERK) on hypoxic-ischemic brain damage of neonatal rats.Methods The hypoxic-ischemic brain damage model of neonatal Wistar rats was established as following:first the right common carotid artery of the rats was ligated;2 h after operation,the rats began to inhale 8%-oxygen oxygen-nitrogen gas mixture lasting for 2 h.Rats were randomly divided into three groups:sham-group,hypoxic-ischemic group and ERK inhibitor PD98059 group (the rats were injected PD98059 2 mg/kg 10 min before the ligation).Six hours after the models were done,hippocampi and cortex of the ligation side of rats in the three groups were collected,and the levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were measured.Apoptosis of neuron was assessed by TUNEL staining.The expression of ERK1,ERK 2,Bcl-2 and Bax were examined by Western blot.The differences among the groups were analyzed with ANOVA and q test.Results Compared with the sham-group,the MDA level [(342.9± 10.8) μmol/L vs (181.5± 17.0) μmol/L,q= 6.35,P＜0.01) and the apoptosis rate of neuron [(18.80±1.37)% vs (3.53±0.34)%,q=6.06,P＜0.01) of hypoxic-ischemic group was higher,and SOD level was lower [(34.8±4.3) U/ml vs (63.4±4.3) U/ml,q=4.99,P＜0.01].While the apoptosis rate of neuron [(15.53±0.64) %] and MDA level [(252.0± 17.1) μmol/L] of PD98059 group were lower than those of hypoxic-ischemic group(q=3.87 and 5.28,P＜0.01respectively),the SOD level [(51.5 ± 3.8) U/ml] was higher than that of hypoxic-ischemic group (q=4.17,P＜0.01).There were no differences of ERK1 and ERK2 expressions among the three groups.The phosphorylated ERK1 and ERK2 levels of hypoxic-ischemic group were higher than those of sham-group (q=3.82 and 4.08,P＜0.01) and PD98059 group (q=4.79 and 5.12,P＜0.01).The expression of Bcl-2 and Bax of hypoxic-ischemic group were higher than those of sham-group (q=3.55 and 3.42,P＜0.01).Compared with hypoxic-ischemic group,Bcl-2 expression (q=3.71,P＜0.01) of PD98059 group was higher,and Bax expression (q=5.86,P ＜ 0.01) was lower.Conclusions ERK is involved in hypoxic-ischemic brain damage of neonatal rats through regulating the expression of apoptosis protein.     

Caspase-3 持续激活时程与新生大鼠缺氧缺血性脑损伤

目的　探讨Caspase 3在新生大鼠缺氧缺血性脑损伤后期的表达情况及其与神经元凋亡的关系。　方法　新生大鼠缺氧缺血性脑损伤模型 ,在损伤后不同时间 (2、3和 4周 )随机分为 3组 ,每组每个时间点各 5只鼠。用半定量RT PCR观察新生大鼠缺氧缺血性脑损伤后期Caspase 3mRNA表达及用免疫组化方法观察Caspase 3蛋白表达情况 ;用TUNEL方法检测不同时程细胞凋亡情况。　结果　缺氧缺血后 3周时Caspase 3mRNA水平为 (0 .771± 0 .0 74 ) ,仍高于对照组的(0 .6 2 0± 0 .0 38,P <0 .0 1) ,Caspase 3蛋白表达 (平均吸光度A值 0 .375± 0 .0 38) ,亦强于对照组(0 .35 6± 0 .0 2 0 ) (P <0 .0 5 )。缺氧缺血后 4周时 ,缺氧缺血性脑损伤组与对照组比较 ,Caspase 3mR NA表达及其蛋白表达差异均无显著性 (P >0 .0 5 )。HI后 3周时左脑凋亡细胞数为 (8.0 0± 1.0 0 )个 ,与正常组 (4 .2 0± 1.30 )个比较 ,差异有显著性 (t=5 .17,P <0 .0 1) ;在HI后 4周时左脑凋亡细胞数 (4 .0 0± 1.0 0 )个 ,与对照组比较差异无显著性 (t=0 .2 7,P >0 .0 5 )。HI后 3周时脑组织DNA断裂百分率为 (8.19± 2 .4 9) % ,与正常组 (3.0 4± 0 .12 ) %比较 ,DNA断裂百分率之间差异有显著性 (t =4 .6 2 ,P <0 .0 5 ) ,而HI后 4周时则差异无显     

体外操作对人卵母细胞线粒体膜电位影响的研究

目的 比较体外不同操作对人卵母细胞线粒体膜电位的影响。方法 利用JC-1试剂盒检测人卵母细胞在体外成熟培养、玻璃化冷冻解冻、卵胞质内单精子注射(ICSI)前后的线粒体膜电位变化,从而得出体外不同操作对线粒体膜电位的影响及卵母细胞质量与线粒体膜电位的关系。结果 卵母细胞在体外正常培养成熟、成熟卵母细胞玻璃化冷冻解冻及卵母细胞显微操作过程中线粒体膜电位均无统计学变化(P0.05)。体外成熟培养失败及单精子注射后受精失败的卵母细胞线粒体膜电位有明显下降(P0.05)。结论 体外常规操作对卵母细胞线粒体膜电位并无显著影响,但是线粒体膜电位与卵母细胞质量有密切关系,可以作为检验卵母细胞质量的一个重要指标。     

茶多酚对新生大鼠卵巢发育的影响

目的:探讨茶多酚对新生大鼠卵泡发育和卵母细胞凋亡的影响及相关调控机制。方法:受孕11.5dSD大鼠灌胃茶多酚(100mg/kg,qd)直至分娩,分别用多聚甲醛固定出生后1d、2d、4d、8d龄雌仔鼠卵巢(A组),同时将正常出生后1d的雌幼SD大鼠腹腔注射茶多酚(50mg/kg×1-8d),分别固定出生后2d、4d、8d龄卵巢(B组);所有卵巢经HE染色,观察不同发育阶段的卵泡比例,TUNEL(TdT-mediated dUTP Nick-End Labeling)荧光染色检测卵巢内卵母细胞凋亡变化,免疫组化方法观察叉头转录因子(FOXO3a)、促凋亡因子(Bim)和抗凋亡因子(MnSOD2)在卵巢组织中的表达水平,并以母、幼均未处理的正常同龄大鼠卵巢为对照(C组)。结果:在茶多酚干预组(包括A组和B组)卵巢内,1d、2d龄未装配卵泡比例及4d、8d龄原始卵泡比例均高于C组;A组、B组中卵母细胞TUNEL阳性率显著低于C组;FOXO3a、MnSOD2在A组的1d、2d、4d龄卵巢中的表达高于C组,但二组间的Bim表达水平相一致。结论:茶多酚能延缓新生大鼠卵母细胞巢破裂,抑制原始卵泡的发育启动,减少卵泡的消耗,可能有益于延长卵巢的生殖寿命;茶多酚可能通过上调FOXO3a的活性从而抑制原始卵泡的发育启动,同时通过激活其下游靶分子MnSOD2抑制卵母细胞的凋亡,促进卵母细胞的存活。     

miR-184通过JNK信号通路调控卵巢癌的增殖与凋亡

目的:探讨miR-184通过JNK信号通路对卵巢癌增殖与凋亡的影响。方法:收集卵巢癌患者的癌组织与癌旁组织标本,荧光定量PCR检测miR-184表达;采用Lipofectamine 2000将miR-184 inhibitor和miR-184 mimic分别转入卵巢癌细胞株OVCAR3,qPCR检测其转染效率,MTT及细胞凋亡实验检测miR-184表达对细胞增殖及凋亡的影响;Westerm blot检测miR-184表达对JNK信号通路中total JNK及p-JNK蛋白的影响。结果:卵巢癌组织中miR-184表达较癌旁组织明显升高,差异有统计学意义(P0.05);高表达miR-184后,OVCAR3细胞增殖率显著提高,细胞凋亡率显著下降,磷酸化p-JNK表达明显上调(P均0.05);下调miR-184表达后,OVCAR3细胞增殖率明显下降,细胞凋亡率显著升高,磷酸化p-JNK表达明显下调(P均0.05)。结论:miR-184可促进卵巢癌细胞增殖并抑制细胞凋亡,其机制可能与JNK信号通路有关。     

PI3K/Akt信号通路与卵巢早衰相关性的研究进展

近年研究发现,PI3K/Akt信号通路参与卵巢早衰(POF)疾病发生。磷脂酰肌醇3-激酶(PI3K)和蛋白激酶B(Akt)的过度激活可使原始卵泡过早发育及卵泡过快凋亡,进而发展成为POF。本文就关于PI3K/Akt信号通路与POF关系的研究进展做一综述。     

阻断PI3K/PKB通路对卵巢癌OVACA-3细胞株增殖和凋亡的影响

目的采用PI3K/PKB信号传导通路特异性抑制剂LY294002作用于人卵巢癌OVACA-3细胞,观察阻断PI3K/PKB信号传导通路对卵巢癌细胞增殖和凋亡等生物学特性的影响,揭示阻断PI3K/PKB信号传导通路治疗卵巢癌的机理和可行性。方法不同浓度的PI3K抑制剂LY294002作用于人卵巢癌OVACA-3细胞后,运用Western Blotting检测P-AKT及细胞核内NF-κBp65表达情况;MTT法、Annexin V-FITC流式细胞技术检测不同浓度的LY294002对卵巢癌OVACA-3细胞增殖及凋亡的影响。结果 LY294002可抑制人卵巢癌OVACA-3细胞中通路效应蛋白AKT、NF-κBp65的激活,且呈浓度及剂量依赖性。LY294002对细胞增殖抑制作用具有时间依赖性(F=10.398,P=0.001)和剂量依赖性(F=9.801,P=0.002)。LY294002可使卵巢癌细胞S期比例显著减少,G0/G1期比例增多,提示LY294002促使细胞在细胞周期G0-G1期受到阻滞。最终,抑制卵巢癌细胞增殖,促使其发生细胞凋亡,使细胞周期停滞在G1期。结论 PI3K/PKB信号传导通路阻断剂LY294002有可能成为治疗卵巢癌的新药,阻断PI3K/AKT信号传导通路可作为治疗卵巢癌的新切入点。     

清肺通络膏对呼吸道合胞病毒感染大鼠肺组织PI3K-AKT-NFκB信号通路的影响

目的观察清肺通络膏对呼吸道合胞病毒(RSV)感染大鼠肺组织PI3K、AKT1/2、NF-κB p65蛋白表达的影响,探讨清肺通络膏对PI3K/AKT/NF-κB信号通路的调控机制。方法将30只SD大鼠随机分为正常组、模型组、治疗组各10只,模型组、治疗组均给予RSV滴鼻接种3d,治疗组于接毒第1天予清肺通络膏背部贴敷,连续7d。于造模第7天后取大鼠肺组织,运用免疫组织化学染色法检测各组大鼠肺组织中PI3K、AKT1/2、NF-κB p65蛋白的表达。结果与正常组比较,模型组大鼠肺组织PI3K、AKT1/2、NF-κB p65蛋白表达增多,差异有统计学意义(P0.05)。治疗组大鼠肺组织PI3K、AKT1/2、NF-κB p65蛋白表达均低于模型组,差异有统计学意义(P0.05)。结论 RSV感染大鼠时激活了PI3K/AKT/NF-κB信号通路,清肺通络膏能够抑制PI3K、AKT1/2、NF-κB p65蛋白的表达,可能是清肺通络膏干预RSV肺炎的机制之一。     

DKK3、Wnt/β-连环蛋白信号通路与宫颈癌关系的研究进展

宫颈癌为女性恶性肿瘤之一,对于其发病机制及所涉及的通路分子的研究越来越深入。其中Wnt/β-连环蛋白（β-catenin）信号通路的研究受到高度关注。Wnt/β-catenin信号通路涉及广泛的生理和病理过程,包括细胞生长、分化、个体发育、迁移、遗传稳定性、凋亡、干细胞自我更新和维持成人组织稳态。稳定的β-catenin在细胞质中积累并转移到细胞核,激活Wnt/β-catenin信号通路,是多种癌症的诱发因素之一。β-catenin的积累在Wnt/β-catenin信号通路占据核心位置。β-catenin通过Wnt/β-catenin信号通路驱动靶基因,参与宫颈癌多步骤的发生及发展。而Dickkopf相关蛋白3（DKK3）可能通过降解β-catenin、阻断β-catenin的核转运,抑制Wnt/β-catenin信号通路,在抑制宫颈癌的发生、发展中发挥潜在作用。因此,深入研究DKK3、Wnt/β-catenin信号通路与宫颈癌的关系,显得尤为重要。     

SHBG expression is correlated with PI3K/AKT pathway activity in a cellular model of human insulin resistance

Decreased sex hormone-binding globulin (SHBG) expression is an independent risk factor for gestational diabetes mellitus(GDM).However, the mechanisms that link low SHBG expression and insulin resistance in GDM is unclear. In this study, we investigated the placenta SHBG in the PI3K/AKT pathway to reveal the mechanism that links decreased SHBG to insulin resistance. A insulin resistance cells model was established by the method of insulin stimulation. Two groups were set up, HTR8/Svneo cells and insulin-resistance cells of HTR8/SVneo. The expression of SHBG and PI3K/AKT associated factors were detected using real-time PCR and western blotting and their correlations were analyzed. The results showed that SHBG protein and mRNA levels in insulin resistance cells were both significantly lower. Along with decreased SHBG expression, the mRNA and protein levels of IRS-1, IRS-2, PI3Kp85α and GLUT-3, GLUT-4 decreased significantly. However, the expression of GLUT-1 increased significantly. Pearson correlation analysis showed that SHBG mRNA expression was positively correlated with IRS-1, IRS-2 and PI3Kp85α mRNA levels. According to the results, low SHBG expression not only participates in the development of local insulin resistance, but may also play an important role in PI3K/AKT pathway-mediated systemic insulin resistance and gestational diabetes.