Molecular changes induced by bisphenol-A in rat Sertoli cell culture

Bisphenol-A (BPA) is an industrial chemical and is known to act as an endocrine disrupter. This study was designed to evaluate how BPA regulates Sertoli cell (SC) signal molecules. Purified rat SCs were cultured and treated with BPA (200?μmol/l) at various time points. Western blot analysis was used to determine the activation of extracellular signal-related kinases 1 and 2 (ERK1/2), c-Jun N-terminal kinase (JNK), p38 mitogen activated protein kinase (MAPK), nuclear factor kappa B (NF-κB), cyclooxygenase-1,2 (COX-1, 2), estrogen receptor-α (ER-α), and androgen receptor (AR). The levels of transferrin (TF), prostaglandin E(2) (PGE(2)), and prostaglandin F(2α) (PGF(2α)) in culture medium were quantified by ELISA. Interleukin (IL)-1β and IL-6 mRNAs were measured by quantitative real-time PCR (QRT-PCR). Compared with the control, BPA activated the phosphorylation of ERK1/2 (p-ERK1/2) through 30?min to 6?h. TF was down-regulated at 6 and 24?h. Furthermore, IL-1β was up-regulated at 30?min and IL-6 was up-regulated at 1 and 24?h. ERK activity inhibitor (PD98059, 10?μmol/l) inhibited these molecular changes. These results reveal the possibility that BPA may have adverse effects on spermatogenesis via ERK1/2.     

Effect of antispermatogenic agents on cell marker enzymes of rat Sertoli cells in vitro

OBJECTIVE: To examine the role of Sertoli cells in the antispermatogenic action of two nonsteroidal male contraceptive compounds (CDRI-84/35 and gossypol) by evaluating their effect on some key parameters of Sertoli cell function in vitro. METHODS: Primary cultures of Sertoli cell were established from 18-day-old rat testis and treated on day 5 with different concentrations (1.0, 0.1, 0.01, and 0.001 mM) of either CDRI-84/35 or gossypol in vitro. Lactate (secretion), along with beta-glucuronidase, gamma-glutamyl transpeptidase, lactate dehydrogenase (LDH) and aromatase activities, was measured in these cells to examine the functions targeted by antispermatogenic agents in Sertoli cells. RESULTS: CDRI-84/35 significantly affected Sertoli cell parameters (stimulation in most of the cases) that are important for germ cell development like lactate secretion, LDH activity, aromatase activity (estradiol secretion) and so on. Gossypol in comparison to CDRI-84/35 had a more severe effect on Sertoli cells with complete inhibition of enzyme activities at higher concentrations. CONCLUSION: It is probable that the antispermatogenic action of CDRI-84/35 and gossypol is routed through Sertoli cells by disruption of important cell functions that support spermatogenesis in vivo. However, the two compounds appear to have different course of action in Sertoli cells, ultimately leading to spermatogenic failure.     

丙烯腈对原代双室培养的大鼠睾丸支持细胞的毒性

[目的]研究丙烯腈(ACN)对原代双室培养的大鼠睾丸支持细胞(Sertolicell,Sc)的毒性,以探讨ACN诱导雄性生殖毒性机制。[方法]用已分离纯化的大鼠睾丸SC为材料,用原代双室培养方法,加和不加S9,以浓度为0、0.5、5.0、25.0μg/mlACN染毒,于4、12、24、48h后检测跨细胞上皮电阻(TER);染毒24、48h后检测转铁蛋白(Trf)浓度,评价ACN体外染毒对大鼠睾丸SC的损伤。[结果]ACN浓度≥5.0μg/ml时,对TER的形成有明显抑制作用;5.0μg/ml培养48h、25.0μg/ml培养12h后对已形成的TER引起下降;加S9( S9)与不加S9(-S9),TER值接近(如25.0μg/ml组培养12h后 S9组为480.3,-S9组为486.3),无明显差异。浓度为25.0μg/ml时,ACN染毒引起外室Trf浓度升高,明显高于对照及其他组(P<0.05),内室Trf浓度变化不明显,因此内室与外室之间Trf浓度差值缩小。[结论]结果表明ACN对双室培养的SCTER的形成有抑制作用,对已形成的TER有降低作用;提示ACN可能对SC形成的紧密连接和“血睾屏障”有影响。     

氟对大鼠脑组织α7尼古丁受体和ERK1/2影响

目的 研究氟对α7神经型尼古丁受体和细胞外信号调节蛋白激酶(ERK1/2)通路的影响。方法 SD大鼠随机分为3组,即对照组、低剂量染氟组、高剂量染氟组;实验6个月后,取大鼠脑组织,用蛋白印迹方法及实时荧光定量PCR方法分别检测尼古丁受体α7亚单位、ERK1/2激酶蛋白和mRNA表达。结果 染氟大鼠脑组织中尼古丁受体α7亚单位蛋白表达降低[对照组(100±11.45)%,低剂量染氟组(45.2±9.2)%,高剂量染氟组(29.6±7.6)%];phospho-ERK1/2和total-ERK1/2蛋白表达升高[对照组(100.0±9.6)%、(100.0±11.7)%,低剂量染氟组(125.4±9.6)%、(132.9±2.1)%,高剂量染氟组(175.3±12.4)%、(207.4±7.4)%];染氟组ERK1/2活化率降低[对照组(100.0±12.2)%,低剂量染氟组(82.9±4.9)%,高剂量染氟组(65.9±3.7)%];染氟组尼古丁受体α7亚单位和ERK1/2 mRNA表达水平无明显改变;ERK1/2活化率与尼古丁受体α7亚单位蛋白表达呈正相关(r=0.696,P<0.05)。结论 慢性氟中毒引起的脑组织ERK1/2信号通路改变可能与神经型尼古丁受体表达水平降低有关。     

青石棉诱导BEAS-2B细胞ERK1/2磷酸化表达的研究

目的 了解青石棉在致癌过程中引起信号转导蛋白变化的特点.方法 使用人呼吸道上皮细胞株（human bronchial epithelial cell line,BEAS-2B）体外培养,以终浓度100 μg/ml的青石棉和100nmoL/L表皮生长因子（epidermal growth factor,EGF）分别刺激BEAS-2B细胞30和120min,使用特异性抗磷酸化细胞外调节蛋白激酶（extracellular regulated protein kinase,ERK1/2）、ERK激酶（ERK kinase,MEK1/2）和抗总ERK1/2、MEK1/2抗体进行Western免疫印迹,检测相应的蛋白表达水平.结果 青石棉刺激BEAS-2B细胞30 min后,可诱导磷酸化ERK1/2的快速高表达,且此高表达可持续至120 min,与对照组比较,差异有统计学意义（P＜0.05）;EGF作为诱导磷酸化ERK1/2的阳性刺激物,在30和120 min两时段内均可诱导ERK1/2的激活,与对照组比较,差异有统计学意义（P＜0.05）;任何时间段刺激BEAS-2B,在对照、青石棉和EGF组间,总ERK1/2表达差异无统计学意义（P＞0.05）.青石棉刺激BEAS-2B细胞30、120 min后,可诱导磷酸化MEK1/2的快速高表达,与对照组比较,差异有统计学意义（P＜0.05）.结论 青石棉可快速诱导BEAS细胞产生磷酸化ERK1/2、MEK1/2蛋白的高表达,提示MAPKs参与了青石棉所致疾病的过程.     

Intrauterine bisphenol A exposure leads to stimulatory effects on Sertoli cell number in rats

Using the optical disector for quantifying cell numbers, we investigated whether oral treatment of rats on days 6-21 of gestation with the weakly estrogenic bisphenol A (BPA, 0.1 or 50 mg/kg) or the highly estrogenic ethinyl estradiol (EE, 0.02 mg/kg) alters testicular histology, in those offspring 9-12 month of age. Since production of male germ cells depends on Sertoli cell number, possible changes in that parameter were investigated using unbiased stereology. Spermatogenesis was qualitatively normal in all groups. BPA increases Sertoli cell number per organ but not when expressed as per gram testis. EE did not affect cell number per organ but did affect numbers on a per gram testis basis due to a lowered testis weight. In contrast to the lowering of Sertoli cell numbers that might have been expected according to the estrogen hypothesis, intrauterine administration of these xenoestrogens in fact resulted in minor increases in Sertoli cell numbers and had no qualitative effect on spermatogenesis.     

三羟异黄酮对人乳腺癌细胞外调节激酶影响

目的探讨三羟异黄酮（genistein）对人乳腺癌细胞株MDA-MB-231细胞外调节激酶1/2（ERK1/2）MAPK信号转导通路的影响.方法采用四甲基偶氮噻唑蓝（MTT）比色法分别检测三羟异黄酮以及与ERK1/2上游激酶MEK1/2抑制剂联合作用时对MDA-MB-231增殖的抑制作用;应用Western blot蛋白免疫印记法分别检测ERK1/2总蛋白、c-Jun、c-Fos蛋白的表达.结果 MTT结果显示,与对照组相比,三羟异黄酮作用48h后,细胞存活度随浓度增加而降低,合用MEK1/2抑制剂细胞存活度最低;Western blot分析提示,随三羟异黄酮剂量的增加,ERK1/2、c-Jun、c-Fos蛋白表达增加,但合用抑制剂后蛋白表达降低.结论三羟异黄酮可以抑制MDA-MB-231细胞增殖,并激活了ERK1/2 MAPK信号转导通路;MEK1/2抑制剂可以抑制三羟异黄酮介导的ERK1/2活化,同时提高三羟异黄酮的肿瘤抑制作用.     

用睾丸细胞共培养探讨吡哆醇对大鼠睾丸细胞的毒性

目的探讨吡哆醇（ＰＮ）对大鼠睾丸的体外毒性。方法采用在Ｗｉｌｉａｍｓ方法的基础上改进的Ｓｅｒｔｏｌｉｇｅｒｍ细胞共培养系统,观察ＰＮ在不同剂量和接触时间对培养细胞的作用。结果脱落生精细胞数随ＰＮ浓度的增高和接触时间的延长而增加,并有明显的剂量—效应和时间—效应关系。同时,还观察到Ｓｅｒｔｏｌｉ细胞骨架出现松弛、回缩等效应。结论ＰＮ对大鼠生精细胞的体外效应反映了其对Ｓｅｒｔｏｌｉ细胞的损害。睾丸细胞共培养方法对探讨ＰＮ对大鼠睾丸的毒性作用具有实用价值。     

Fas／FasL参与热诱导大鼠睾丸生精细胞凋亡的调控

目的：探讨睾丸局部加热致大鼠睾丸生精细胞凋亡及Fas/FasL信号通路在生精细胞凋亡调控中的作用。方法16只成年SD雄性大鼠随机均分为加热组和对照组。加热组进行大鼠睾丸43℃水浴15 min;对照组行大鼠睾丸22℃水浴15 min。24 h后进行灌流和内固定,取睾丸。制作5μm的组织切片,采用睾丸原位末端标记法（TUNEL）和免疫组化分析,检测生精细胞凋亡及 Fas 和 FasL 表达。化学发光法检测大鼠血清睾酮水平。结果加热组睾丸生精细胞凋亡率（15.8％±1.6％）较对照组（2.2％±0.5％）显著增加;加热后Fas和FasL在生精细胞和支持细胞表达水平也明显升高;对照组和加热组血清睾酮（T）水平无差异。结论睾丸局部加热诱导生精细胞凋亡,Fas和FasL系统为该凋亡过程的信号通路之一。     

ATM蛋白激酶-检测点激酶2通路在氟抑制大鼠曲细精管上皮支持细胞增殖中的作用

目的观察ATM蛋白激酶-检测点激酶2(ATM-Chk2)通路在氟抑制大鼠曲细精管上皮支持细胞增殖中的作用。方法将18日龄SPF级雄性SD大鼠曲细精管上皮支持细胞分别暴露于含0(对照)、0.25、0.50、1.00、2.00、4.00 mmol/L氟化钠的血清培养基。分别于染毒24、48、72 h,采用MTT法测定支持细胞的增殖情况;于染毒24 h,采用实时荧光定量PCR技术检测支持细胞内ATM、Chk2 m RNA的表达水平。结果与对照组比较,染毒24、48、72 h时,4.00 mmol/L氟化钠染毒组大鼠曲细精管上皮支持细胞的抑制率均较高,差异有统计学意义(P0.05);且随着氟化钠染毒剂量的升高和染毒时间的延长,氟对曲细精管上皮支持细胞的抑制率均呈上升趋势。与对照组比较,1、2 mmol/L氟化钠染毒组曲细精管上皮支持细胞ATM和Chk2 m RNA的表达水平均升高,而4 mmol/L氟化钠染毒组ATM和Chk2 m RNA的表达水平均降低,差异有统计学意义(P0.05);且随着氟化钠染毒剂量的升高,曲细精管上皮支持细胞ATM、Chk2 m RNA的表达水平均呈下降趋势。结论不同剂量氟抑制生殖细胞增殖可能是通过干扰曲细精管上皮支持细胞中DNA损伤检验点ATM、Chk2的表达而实现的。     

ADAMTS1 and ADAMTS5 metalloproteases produced by Sertoli cells: a potential diagnostic marker in azoospermia

In this study, our aim was to detect protein levels of A Disintegrin and Metalloproteinase with Thrombospondin Motifs 1 and 5 (ADAMTS1 and ADAMTS5) proteases and to examine the effect of in vitro FSH supplementation on protease production in cultured Sertoli cells. The expression of metalloproteases, ADAMTS1, and ADAMTS5 were investigated in Sertoli cell cultures as well as in ejaculate of azoospermic men which then were compared with ejaculates of the fertile control group. A total of 15 azoospermic men, diagnosed as obstructive (OA, n = 5) and nonobstructive (NOA, n = 10) azoospermia were included in the study. ADAMTS1, ADAMTS5 and FSH receptors (FSHR) were found to be expressed 2.56, 2.10, and 2.66-fold less in Sertoli cells of NOA patients, than those of OA (p < 0.05). After rFSH was added onto Sertoli cell cultures of NOA patients, their expression did not increase significantly and did not reach to levels of control group. Evaluation of ejaculates revealed that the expression of ADAMTS1 and ADAMTS5 were insignificantly 1.03 and 1.1-fold higher in OA group (p > 0.05), respectively; however, in the NOA group, their expression were 1.70 and 1.96-fold lower, respectively, when compared with the fertile control group (p < 0.05) which was statistically significant. As a conclusion, the present study has revealed that insufficiency of ADAMTS1 and ADAMTS5 expression in Sertoli cells may have an important role in the etiology of male infertility. As expected due to low FSHR expression, rFSH response is impaired in NOA patients with relatively low ADAMTS expression response; therefore, such patients might hardly benefit from rFSH treatment. Further studies with larger cohorts may reveal ADAMTSs’ potential use as a predictive marker for positive sperm retrieval in azoospermic patients who are scheduled to undergo testicular sperm extraction.

Abbreviations: ADAM: A Disintegrin and Metalloproteinase; ADAMTS1 and ADAMTS5: A Disintegrin and Metalloproteinase with 10 Thrombospondin Motifs 1 and 5; ADAMTS: A Disintegrin and Metalloproteinase with Thrombospondin; ABP: androgen binding protein; CAMs: cell adhesion molecules; ECM: extracellular matrix; FSH: follicle stimulating hormone; FSHR: FSH receptors; HRP: horseradish peroxidase; MMP: matrix metalloproteinases; MP: metalloproteinases; NOA: nonobstructive azoospermia; OA: obstructive azoospermia; TIMP-1: tissue inhibitor of metalloproteinase-1     

IGFBP-rP1通过调控MEK/ERK信号通路对抑制子宫内膜癌HEC-1A细胞增殖的影响及机制探讨

目的:探讨外源性胰岛素样生长因子结合蛋白相关蛋白1 (IGFBP-rP1)联合MEK/ERK信号通路抑制剂PD98059对子宫内膜癌细胞HEC-1A增殖的影响及其机制.方法:体外培养人子宫内膜癌细胞HEC-1A细胞,向培养基中添加不同浓度人重组胰岛素生长因子结合蛋白相关蛋白1 (rhIGFBP-rP1)和PD98059,上调IGFBP-rP1的水平,采用Cell CountingKit-8(CCK-8)法检测不同浓度rhIGFBP-P1及rhIGFBP-P1联合MEK/ERK信号通路抑制剂PD98059对HEC-1A细胞增殖的影响,并用蛋白免疫印迹(western blot)法分析不同浓度rhIGFBP-rP1作用下子宫内膜癌细胞HEC-1A细胞总的ERK1/2和磷酸化ERK1/2水平变化.结果:添加rhIGFBP-rP1子宫内膜癌细胞HEC-1A增殖受到明显抑制,其抑制作用呈浓度和时间依赖性(P＜0.05);4ag/ml rIGFBP-rP1对HEC-1A增殖抑制作用随着时间延长越来越明显,12、24、48、72 h增殖抑制率比较差异有统计学意义(P＜0.05).而MEK/ERK通路抑制剂PD98059能增强其抑制作用,rIGFBP-rP1(4μg/ml)与PD98059(25 μmol/L)联用,以上各时间点细胞增殖抑制率分别增至(10.04±2.71)％、(17.02±1.58)％、(28.59±2.04)％、(35.29±1.12)％,各组比较,差异有统计学意义(P＜0.05);Western blot示添加rhIGFBP-rP1,磷酸化的ERK1/2水平显著降低,磷酸化的ERK1/2水平与rhIGFBP-rP1呈剂量依赖性.结论:IGFBP-rP1可以通过MEK/ERK信号通路抑制细胞增殖.     

碱性成纤维细胞生长因子对卵巢癌的影响

目的观察Ras-Raf-ERK 1/2途径介导的碱性成纤维细胞生长因子(bFGF)对卵巢癌细胞系CAOV3细胞增殖和凋亡影响,探讨bFGF及其信号转导途径与卵巢癌发生发展关系。方法以bFGF和促细胞分裂剂激活性蛋白激酶1(MEK1)抑制剂PD98059处理CAOV3细胞,用四甲基偶氮噻唑蓝(MTT)法检测细胞增殖情况,流式细胞术检测细胞凋亡情况,蛋白印迹(Western blot)检测细胞外信号调节蛋白激酶1/2(ERK1/2)的活性。结果bFGF处理后细胞增殖比明显增加,且与bFGF水平呈剂量依赖关系,bFGF浓度为75 ng/ml时细胞增殖比最高为140%;bFGF使无血清诱导的凋亡细胞比例下降[(33.20±5.32)%~(2.38±3.36)%];bFGF诱导ERK1/2活性增高。PD98059可抑制bFGF的这些作用。结论bFGF通过Ras-Raf-ERK 1/2途径介导,促进卵巢癌CAOV3细胞增殖,抵抗无血清诱导凋亡。在卵巢癌发生发展过程中,bFGF信号传递发挥了重要作用。     

Black rice extract protected HepG2 cells from oxidative stress-induced cell death via ERK1/2 and Akt activation

BACKGROUND/OBJECTIVES

The objective of this study was to evaluate the protective effect of black rice extract (BRE) on tert-butyl hydroperoxide (TBHP)-induced oxidative injury in HepG2 cells.

MATERIALS/METHODS

Methanolic extract from black rice was evaluated for the protective effect on TBHP-induced oxidative injury in HepG2 cells. Several biomarkers that modulate cell survival and death including reactive oxygen species (ROS), caspase-3 activity, and related cellular kinases were determined.

RESULTS

TBHP induced cell death and apoptosis by a rapid increase in ROS generation and caspase-3 activity. Moreover, TBHP-induced oxidative stress resulted in a transient ERK1/2 activation and a sustained increase of JNK1/2 activation. While, BRE pretreatment protects the cells against oxidative stress by reducing cell death, caspase-3 activity, and ROS generation and also by preventing ERKs deactivation and the prolonged JNKs activation. Moreover, pretreatment of BRE increased the activation of ERKs and Akt which are pro-survival signal proteins. However, this effect was blunted in the presence of ERKs and Akt inhibitors.

CONCLUSIONS

These results suggest that activation of ERKs and Akt pathway might be involved in the cytoprotective effect of BRE against oxidative stress. Our findings provide new insights into the cytoprotective effects and its possible mechanism of black rice against oxidative stress.     

镉诱导大鼠腺垂体细胞凋亡及与p38 MAPK&ERK1/2途径介导机制关系的初步研究

目的了解CdCl2对腺垂体的损伤以及细胞凋亡发生与p38MAPK、ERK12表达的关系,为了解镉致腺垂体毒作用的分子机制提供科学依据。方法采用健康雄性SD大鼠进行整体试验(n=12),分别每天经口灌胃给予0、1.0、2.0、4.0mgkgbwCdCl2,6周后取腺垂体进行指标检测;离体试验采用酶解分离大鼠之原代腺垂体细胞,分别以0、1.56、3.12、6.25、12.50、25.00、50.00、100.00μmolLCdCl2处理,收获细胞进行检测;特异性阻断剂阻断凋亡效应的试验采用2.65μmolLp38MAPK的特异阻断剂SB203580或10μmolLERK12激酶的特异阻断剂U0126处理细胞,然后以3.12μmolL或100.00μmolL的CdCl2处理细胞后进行相应的检测。检测指标包括:TUNEL法和流式细胞术等检测凋亡。结果整体实验和离体实验结果均显示CdCl2以剂量依赖方式诱导腺垂体细胞发生凋亡(P<0.05);特异性阻断剂效应的研究结果显示2.65μmolLSB203580和10μmolLU0126对TUNEL阳性细胞的相对灰度和凋亡细胞率均有一定的影响。结论在一定的剂量条件下,CdCl2影响腺垂体激素分泌水平,并导致发腺垂体细胞凋亡,MAPKs家族成员p38MAPK和ERK12激酶通路在凋亡发生过程中可能发挥一定的作用。     

Effects of decabrominated diphenyl ether (PBDE-209) in regulation of growth and apoptosis of breast, ovarian, and cervical cancer cells

Background: Polybrominated diphenyl ethers (PBDEs), commonly used in building materials, electronics, plastics, polyurethane foams, and textiles, are health hazards found in the environment.Objective: In this study we investigated the effects of PBDE-209, a deca-PBDE, on the regulation of growth and apoptosis of breast, ovarian, and cervical cancer cells as well as the underlying protein alterations.Methods: We used MCF-7 and MCF-7/ADR (multidrug-resistant MCF-7) breast cancer cell lines, the HeLa cervical cancer cell line, the OVCAR-3 ovarian cancer cell line, and the normal CHO (Chinese hamster ovary) cell line to assess the effects of PBDE-209 using cell viability, immunofluorescence, and flow cytometric assays. Western blot assays were used to detect changes in protein expression. To assess the effects of PBDE-209 on apoptosis, we used the protein kinase Cα (PKCα) inhibitor Gö 6976, the extracellular signal-regulated kinase (ERK) inhibitor PD98059, and tamoxifen.Results: Our data indicate that PBDE-209 increased viability and proliferation of the tumor cell lines and in CHO cells in a dose- and time-dependent manner. PBDE-209 also altered cell cycle distribution by inducing the S phase or G₂/M phase. Furthermore, PBDE-209 partially suppressed tamoxifen-induced cell apoptosis in the breast cancer cell lines (MCF-7 and MCF-7/ADR) but suppressed Gö 6976- and PD98059-induced apoptosis in all cell lines. At the molecular level, PBDE-209 enhanced PKCα and ERK1/2 phosphorylation in the cell lines.Conclusions: Our data demonstrate that PBDE-209 is able to promote proliferation of various cancer cells from the female reproductive system and normal ovarian CHO cells. Furthermore, it reduced tamoxifen, PKCα, and ERK inhibition-induced apoptosis. Finally, PBDE-209 up-regulated phosphorylation of PKCα and ERK1/2 proteins in tumor cells and in CHO cells.     

ERK信号转导通路在CdCl2诱导HEK293细胞低剂量兴奋效应中的作用

目的 探讨ERK信号转导通路在CdCl2诱导HEK293细胞低剂量兴奋效应过程中的作用.方法 以0、0.0005、0.005、0.05、0.5、5、50和500μmol/L浓度的氯化镉(CdCl2)分别染毒HEK293细胞12h和24h;在染毒前分别用ERK1/2抑制剂PD98059(100μmol/L)、U0126(...     

碘缺乏和甲状腺功能减退对大鼠仔鼠海马ERK1/2表达的影响

目的观察碘缺乏和甲状腺功能减退对大鼠仔鼠海马细胞外信号调节蛋白激酶1及2(ERK1/2)表达的影响。方法健康2月龄孕Wistar大鼠28只,按体重随机分成对照组、甲状腺功能减退组[按饮水中含丙基硫尿嘧啶(PTU)剂量分为5mg/L组和15mg/L组]和碘缺乏组,每组7只。分别于出生后第7、14、21、28和42天每组随机取5只仔鼠,灌流固定大脑,用组织病理切片和免疫组化染色观察分析海马的ERK1/2表达。结果在出生后14、21、28和42天时,海马CA1和CA3区的ERK1/2表达在PTU5mg/L组、PTU15mg/L组和碘缺乏组显著低于对照组(P0.05)。DG区的ERK1/2表达与对照组相比差异无显著性。出生后7天时,各组间ERK1/2表达差异无显著性。结论碘缺乏和甲状腺功能减退可降低海马CA1和CA3区的ERK1/2表达。     

AP-1在锌离子诱导BEAS-2B细胞COX-2基因转录中作用

目的探讨外源性锌离子对人支气管上皮细胞环氧化酶2(COX-2)基因诱导表达及转录因子激活蛋白-1(AP-1)的转录活性调节作用。方法以人支气管上皮细胞株BEAS-2B作为体外模型,Real-time PCR方法检测锌离子对BEAS-2B细胞COX-2基因表达影响;染色质免疫沉淀(ChIP) 实验检测50.0 μmol/L锌离子温育8 h后c-Jun(AP-1亚单位)和COX-2启动子的结合;用野生型和AP-1结合位点突变的COX-2启动子报告质粒转染BEAS-2B细胞,50.0 μmol/L锌离子温育8 h,采用荧光素酶报告基因检测COX-2基因启动子转录活性。结果 50.0 μmol/L Zn²⁺组BEAS-2B细胞中COX-2的mRNA相对表达量为(1.23±0.16),是对照组表达量(0.16±0.02)的7.68倍,表达明显升高(P<0.5);AP-1可与COX-2的基因启动子结合,COX-2基因启动子区AP-1结合位点突变可使锌离子所致的COX-2高转录活性降低82%。结论 转录因子AP-1可调节外源性锌离子所致人支气管上皮细胞COX-2基因的转录表达。