滋养细胞内质网应激特征性分子葡萄糖调节蛋白及内质网凋亡因子caspase-12与子痫前期发病的关系

目的 探讨滋养细胞内质网超微结构变化及内质网应激特征性分子--内质网分子伴侣葡萄糖调节蛋白(GRP)78、94和内质网凋亡因子--半胱氨酸天冬氨酸蛋白酶12(caspase-12)mRNA及蛋白表达与子痫前期发病的关系.方法 选择2008年7月-2010年1月在南京医科大学第一附属医院分娩的孕妇共65例,其中子痫前期孕妇30例(子痫前期组),健康孕妇35例为对照组.应用透射电镜扫描观察胎盘组织中滋养细胞内质网超微结构改变,逆转录(RT)PCR技术检测胎盘组织中GRP78、GRP94和caspase-12 mRNA的表达,蛋白印迹法检测胎盘组织中GRP78、GRP94和caspase-12蛋白的表达.结果 (1)对照组胎盘组织中滋养细胞内质网体积无明显增大,内质网无扩张也无肿胀变化;子痫前期组滋养细胞内质网水肿,数量减少,内质网体积增大,内质网扩张及液泡化,且内质网脱颗粒改变明显.(2)子痫前期组胎盘组织中GRP78 mRNA及蛋白表达水平分别为2.59±0.09及0.81±0.31,显著高于对照组的1.16±0.07及0.40±0.10,两组分别比较,差异均有统计学意义(P<0.01).(3)子痫前期组胎盘组织中GRP94 mRNA和蛋白表达水平分别为1.31±0.91及0.55±0.24,显著高于对照组的0.63±0.57及0.22±0.09,两组分别比较,差异均有统计学意义(P<0.01).(4)子痫前期组胎盘组织中caspase-12 mRNA和蛋白表达水平分别为4.03±0.65及1.56±0.17,显著高于对照组的1.85±0.85及0.91±0.69,两组分别比较,差异均有统计学意义(P<0.01).结论 子痫前期孕妇的滋养细胞内质网有明显的扩张及肿胀性改变;胎盘组织中GRP78、GRP94以及caspase-12 mRNA及蛋白表达水平比健康孕妇有明显升高.提示,内质网应激介导的滋养细胞凋亡可能是子痫前期发病的又一重要机制.     

葡萄糖调节蛋白78在围生医学中的研究进展

作为热休克蛋白70家族成员之一的葡萄糖调节蛋白78（glucose regulation protein 78,GRP78）,不仅是细胞内重要的分子伴侣,也是内质网应激的特异性标志分子,在蛋白质的折叠、转运过程中发挥重要作用,通过多种途径调节细胞内环境的稳定,维持细胞存活。近年研究发现,GRP78在妊娠特发疾病如子痫前期、妊娠期糖尿病等产妇的血清及胎盘滋养细胞中高度表达,同时参与到高血压、糖尿病等的慢性并发症中,与多种疾病的发生发展密切相关。现就GRP78的生物学功能及与各种妊娠相关疾病的关系进行分析与总结,探讨该蛋白是否具有预测作用,为围生期相关疾病的预防及治疗提供新思路。     

内质网应激介导的细胞凋亡在子宫内膜异位症发病中的作用研究

目的探讨内质网应激介导的细胞凋亡在子宫内膜异位症(endometriosis,EM)发病中的作用。方法选取2009年1月至2010年12月沈阳市第五人民医院妇产科32例EM患者的异位和在位子宫内膜组织,选取同期28例因浆膜下子宫肌瘤手术并经病理证实为正常子宫内膜组织为对照组。采用流式细胞仪检测子宫内膜细胞凋亡率,采用RT-PCR法检测子宫内膜内质网分子伴侣葡萄糖调节蛋白-78(glucose-regulated protein78,GRP-78)、葡萄糖调节蛋白-94(glucose-regulated protein94,GRP-94)和凋亡因子Caspase-12、Caspase-3mRNA的表达,采用Western blot法检测子宫内膜GRP78、GRP94和Caspase-12、Caspase-3蛋白的表达。结果 EM患者异位和在位子宫内膜细胞凋亡率均显著低于正常子宫内膜,且异位子宫内膜细胞凋亡率显著低于在位子宫内膜;EM患者异位和在位子宫内膜GRP78、GRP94和Caspase-12、Caspase-3mRNA及蛋白表达水平均显著低于正常子宫内膜,且异位子宫内膜GRP78、GRP94和Caspase-12、Caspase-3mRNA及蛋白表达水平显著低于在位子宫内膜。结论 EM患者子宫内膜细胞凋亡减少,内质网应激介导的细胞凋亡途径下调可能是EM发病的机制之一。     

GRP78 induced by estrogen plays a role in the chemosensitivity of endometrial cancer

Objective

Molecular chaperone 78 kDa glucose-regulated protein (GRP78) is a residential protein in the endoplasmic reticulum (ER) that is induced by an unfolded-protein response triggered under many kinds of stress against a cell. GRP78 is also known to act as an anti-apoptotic factor by protecting ER-stress-induced cell death. In this study, we examined the significance of GRP78 expression in endometrial cancer.

Methods

Tissue samples obtained from patients with a diagnosis of enodometrial cancer were subjected to immunohistochemistry and RT-PCR to determine protein and mRNA expression levels of GRP78 and estrogen receptor α. We used Western blot and RT-PCR to examine whether estrogen induced GRP78 expression in cancer cell lines. Western blots and MTT assays of GRP78 siRNA transfected Ishikawa and HHUA cells were used to demonstrate whether GRP78 is involved in chemoresistence.

Results

GRP78 was highly expressed in well and moderately differentiated endometrial carcinoma. Estrogen induced GRP78 expression, which was correlated with cell viability and resistance to paclitaxel and cisplatin. Western blot analysis indicated that active caspase-3 and the 85-kDa protein poly (ADP-ribose) polymerase (PARP) were increased by incubation with either paclitaxel or cisplatin, suggesting that the apoptotic pathway was involved in cancer-drug-induced cell death.

Conclusions

These results may open up a novel therapeutic strategy for endometrial cancer: namely, the targeting of GRP78 to sensitize the tumor cell to chemotherapy.     

Interleukin-11 up-regulates endoplasmic reticulum stress induced target,PDIA4 in human first trimester placenta and in vivo in mice

Interleukin (IL)11 is a crucial factor for human trophoblast function and placentation. Elevated levels are associated with pregnancy complications including preeclampsia, intrauterine growth restriction (IUGR) and preterm birth. However, the regulation of IL11 in the placenta has not been investigated. We examined the effect of pro-inflammatory cytokines IL1β and TNFα, as well as low oxygen tension (2%) on IL11 levels in first trimester placental villous explants. IL1β upregulated IL11 mRNA and protein, while TNFα and low oxygen had no effect. Using mass spectrometry, we identified protein disulfide isomerase 4 (PDIA4) in IL11-treated first trimester human placental explants (100 ng/ml, 24 h, n = 3), but not PBS control tissues. PDIA4 is a member of the PDI family, also known as endoplasmic reticulum (ER) stress protein (ERP)72. We previously identified GRP78 (a master regulator for ER stress) in human placenta for the first time and demonstrated that IL11 up-regulates GRP78 in the placenta. In this report, we demonstrated that IL11 upregulates PDIA4 protein in human placental villous tissue, HTR8-SVneo trophoblasts (cell line) and in vivo in IL11-treated mouse placenta. We aimed to determine whether IL11 upregulates other ER stress proteins in human first trimester placental villous. IL11 stimulated ERP44, but not GRP94, or PDI. Placental endoplasmic reticulum stress has been postulated in the pathophysiology of preeclampsia and IUGR, but its activation remains elusive. Together, these data suggest that IL11 could trigger an ER stress response in the placenta, which may contribute to obstetric complications such as preeclampsia.     

Endoplasmic reticulum stress responses in placentation - A true balancing act

The unfolded protein response (UPR) is recognized as a key mechanism to promote protein folding and processing in eukaryotes when endoplasmic reticulum stress (ERS) occurs. Some conditions such as hypoxia or glucose deprivation are factors that may elicit ERS response. Recent literature collectively proposes that ERS response is crucial for mammalian reproduction by allowing decidualization and placentation to occur. However, prolonged ERS and activation of UPR pathways can lead to apoptosis and autophagy, which in turn could pose adverse effects on pregnancy outcomes and placentation. ERS associated pregnancy pathologies include intrauterine growth restriction and early-onset preeclampsia. Given these findings, evidence suggests that overactivation of UPR may lead to harmful reproductive circumstances, whereas physiological regulation of ERS response is essential for mammalian reproduction and placental function.In this review, we discuss the dual role of UPR activation with respect to its contribution to placental development as well as pathologies caused by pathway overactivation. In addition, we suggest potential protein markers associated with the UPR, as circulating C-terminal GRP78 or anti-GRP78 autoantibodies which may prove to be of clinical interest.     

The endoplasmic reticulum stress marker,glucose-regulated protein-78 (GRP78) in visceral adipocytes predicts endometrial cancer progression and patient survival

ObjectiveCurrently, accurately identifying endometrial cancer patients at high risk for recurrence remains poor. To ascertain if changes in the endoplasmic reticulum (ER) stress marker, glucose-regulated-protein-78 (GRP78) can serve as a prognosticator in endometrial cancer, we examined GRP78 expression in patient samples to determine its association with clinical outcome.MethodsA retrospective cohort study was conducted in endometrial cancer patients. Archived specimens of visceral adipocytes and paired endometrial tumors were analyzed by immunohistochemistry for GRP78 and another ER stress marker, C/EBP homologous protein (CHOP). Expression of these markers was correlated with clinico-pathological information and outcomes.ResultsGRP78 expression in visceral adipocytes was detected in 95% of the 179 endometrial cancer patients with analyzable visceral adipocytes. Within individual samples, 24% of adipocytes (range, 0–90%, interquartile range 18%–38%) exhibited GRP78 expression. High visceral adipocyte GRP78 expression positively correlated with advanced-stage disease (p = 0.007) and deep myometrial invasion (p = 0.004). High visceral adipocyte GRP78 expression was significantly associated with decreased disease-free survival (DFS) in multivariate analyses (hazard ratio 2.88, 95% CI 1.37–6.04, p = 0.005). CHOP expression paralleled the GRP78 expression in adipocytes (r = 0.55, p < 0.001) and in the tumor (p = 0.018).ConclusionsOur study demonstrates that the ER stress markers, GRP78 and CHOP, are elevated in endometrial cancer patients. Furthermore, GRP78 expression levels in visceral adipocytes from these patients were significantly correlated to disease stage and patient survival. Our results demonstrate, for the first time, that the GRP78 levels in endometrial cancer patients may be a prognosticator and aid with clinical risk stratification and focused surveillance.     

葡萄糖调节蛋白78在子痫前期胎盘滋养细胞中的表达及意义

目的:探讨葡萄糖调节蛋白78( GRP78)在子痫前期孕妇胎盘组织中表达及其与子痫前期发病机制的关系.方法:选择2009年1 ～12月在青岛市市立医院及青岛市第八人民医院住院的子痫前期孕妇120例,其中早发型轻度子痫前期孕妇30例(早发轻度组),晚发型轻度子痫前期孕妇30例(晚发轻度组),早发型重度子痫前期孕妇30例(早发重度组),晚发型重度子痫前期孕妇30例(晚发重度组);另选同期健康孕妇30例为健康孕妇组.采用半定量逆转录-聚合酶链反应(RT-PCR)检测胎盘组织中GRP78mRNA相对表达量;采用免疫组织化学方法、West-ern-Blotting检测胎盘组织GRP78蛋白的表达.结果:①子痫前期各组胎盘组织中GRP78 mRNA表达水平均高于健康孕妇组,差异有统计学意义(P＜0.05);但子痫前期各组间分别比较,差异无统计学意义(P＞0.05).②子痫前期各组和健康孕妇组胎盘组织中都有GRP78蛋白表达,主要表达于细胞质,呈棕黄色染色.Western-Blotting检测结果显示,子痫前期各组胎盘组织中GRP78蛋白表达水平均高于健康孕妇组,差异有统计学意义(P＜0.05);但子痫前期各组间分别比较,差异无统计学意义(P＞0.05).结论:GRP78在子痫前期胎盘组织中表达升高,GRP78的表达水平变化可能与子痫前期发病有关.     

BIK and GRP78 protein expression as possible markers of response to preoperative chemotherapy and survival in breast cancer

ObjectiveBIK and GRP78 have shown differential expression profiles in breast cancer (BC) tissue, in addition to its important participation in the pathophysiology of cancer. The purpose of this study was to evaluate the association of BIK and GRP78 protein expression with clinical and pathologic response to preoperative chemotherapy, recurrence, disease-free survival (DFS) and overall survival (OS), in patients with BC.Material and methodsFifty-three patients who received preoperative chemotherapy where included in an observational, analytical and retrospective study to assess the BIK and GRP78 protein expression by immunohistochemistry in microarrays of BC tissue obtained before treatment. Associations between BIK and GRP78 expression with clinicopathological characteristics, clinical and pathologic response to preoperative chemotherapy, and recurrence were analyzed using Chi-square or Fisher's exact test. OS and postoperative DFS were assessed at 5-year follow-up by Kaplan-Meir curves, and the difference according to BIK and GRP78 expression was evaluated using the log-rank test. Bivariate analysis was performed using Cox risk proportion model. A p value < 0.05 was considered to be statistically significant.ResultsBIK and GRP78 staining revealed positive expression in 37 (71.2%) and 35 patients (72.9%) respectively. Association between pathological complete response (pCR) and positive expression of BIK (p = 0.046), as well as between clinical complete response (cCR) and negative expression of GRP78 was observed (p = 0.048). Patients with expression of GRP78 had lower DFS (HR = 3.46; 95% CI 1.01–11.80; p = 0.047) and shorter OS (HR = 3.49; 95% CI 1.04 a 11.72; p = 0.043).ConclusionWhen finding association of GRP78 and BIK protein expression with the response (clinical and pathologic respectively) to preoperative chemotherapy, and GRP78 with DFS and OS, in patients with BC, our results suggest a potential prognostic value of both proteins; however, a larger sample size is required to confirm this.     

子宫动脉阻断后腺肌病在位及病灶内膜组织凋亡现象观察

目的:观察子宫动脉阻断后腺肌病病灶内膜及在位子宫内膜凋亡现象;揭示子宫动脉阻断术治疗子宫腺肌病的治疗机制。方法:选择同济大学附属杨浦医院收治的子宫腺肌病患者10例,均行腹腔镜下双侧子宫动脉阻断术,子宫动脉阻断前及阻断后30min分别取子宫腺肌病病灶及在位子宫内膜组织标本各10g,子宫动脉阻断前标本为对照组。运用日本电子电镜观察组织细胞线粒体等亚细胞器结构变化,并采用Real-time PCR、Western blot法检测比较子宫动脉阻断前后子宫内膜及腺肌病组织中凋亡相关分子(Bcl-2、Bax、cyt-c、AIF、caspase-3、caspase-4、caspase-8、caspase-9、Endo-G、apf-1、GRP78、CHOP和TRADD)的表达情况。结果:电镜显示,子宫动脉阻断后子宫腺肌病病灶及在位子宫内膜出现了线粒体内嵴模糊、消失,线粒体肿胀明显,空泡样改变。核染色质边移,细胞膜反折;胞质浓缩,形成凋亡小体等凋亡改变。与子宫动脉阻断前比较,阻断后腺肌病病灶和在位子宫内膜组织中线粒体及内质网途径相关凋亡因子均出现显著性变化,差异有统计学意义(P0.05)。结论:子宫动脉阻断后可诱导腺肌病病灶及在位子宫内膜发生凋亡。缺氧所致细胞凋亡主要为线粒体途径,内质网途径协同参与。缺氧诱导细胞凋亡可能是子宫动脉阻断治疗子宫腺肌病的主要机制。     

2脱氧葡萄糖诱导葡萄糖调节蛋白78表达上调对宫内窘迫胎鼠脑神经元的保护作用

目的 探讨2-脱氧葡萄糖(2DG)诱导葡萄糖调节蛋白78(GRP78)表达上调对宫内窘迫胎鼠的脑神经元凋亡及内质网一线粒体联合作用的影响.方法 (1)建立胎鼠宫内窘迫模型后随机分为正常组(10只)、缺血缺氧再灌注组(40只,再灌注3 h、6 h、12 h、24 h)及治疗组(40只,宫内窘迫模型制备成功后即刻腹腔注射2DG 100 mg/kg体重,再灌注3 h、6 h、12 h、24 h).(2)采用末端脱氧核苷酸转移酶介导的脱氧尿苷三磷酸标记(TUNEL)法检测胎鼠脑神经元凋亡情况及2DG对其的影响;蛋白印迹(western blot)法检测GRP78、半胱氨酸天冬氨酸蛋白酶(caspase)9、12及细胞色素C蛋白的表达水平,观察其与胎鼠脑神经元凋亡的关系及2DG对其的影响.结果 (1)正常组胎鼠阳性细胞数为(4.3±1.8)个/mm2;GRP78、caspase-9、-12、细胞色素C蛋白表达水平分别为0.012±0.003、0.004±0.003、0.006±0.002、0.012±0.005.(2)缺血再灌注组胎鼠再灌注3 h、6 h、12 h、24 h的阳性细胞数分别为(43.6±11.4)、(64.4±9.3)、(74.2±12.1)及(97.3±8.9)个/mm2,与正常组比较,差异有统计学意义(P＜0.05);GRP78蛋白表达水平分别为0.092±0.008、0.078±0.006、0.054±0.009、0.038±0.007,细胞色素C蛋白表达水平分别为0.040±0.006、0.076±0.009、0.108±0.005、0.089±0.008,caspase-9蛋白表达水平分别为0.042±0.003、0.086±0.007、0.142±0.006、0.112±0.009,caspase-12蛋白表达水平分别为0.076±0.006、0.113±0.010、0.125±0.005、0.057±0.008,均明显高于正常组(P＜0.05).(3)治疗组再灌注3 h、6 h、12 h、24 h的阳性细胞数分别为(19.4±10.6)、(26.4±12.3)、(39.3±13.3)及(49.3±13.6)个/mm2,与缺血再灌注组各时间点比较虽明显减少,但仍高于正常组(P＜0.05);GRP78蛋白表达水平分别为0.158±0.012、0.175±0.005、0.125±0.013、0.079±0.004,与缺血再灌注组各时间点及正常组比较,均明显升高(P＜0.05);细胞色素C蛋白表达水平分别为0.026±0.002、0.042±0.008、0.062±0.007、0.045±0.004,caspase-9蛋白表达水平分别为0.033±0.002、0.063±0.005、0.092±0.005、0.068±0.008,caspase-12蛋白表达水平分别为0.061±0.004、0.068±0.009、0.072±0.007、0.054±0.005,与缺血再灌注组各时间点比较虽然均明显减少,但仍高于正常组(P＜0.05).结论 内质网和线粒体共同参与了宫内窘迫胎鼠脑神经元凋亡进程.2DG通过诱导GRP78表达的上调对抗了内质网应激导致的细胞损害,对宫内窘迫胎鼠脑神经元具有良好的保护作用.     

Endoplasmic reticulum stress is activated in endometrial adenocarcinoma

Objectives

Endometrial cancer is the most common malignancy of the female genital tract. However, in spite of a huge advance in our understanding of endometrial cancer biology, therapeutic modalities haven't significantly changed over the past 40 years. The activation of the Unfolded Protein Response (UPR) and GRP78 increase following Endoplasmic Reticulum (ER) stress have been recently identified as mechanisms favoring growth, invasion and resistance to therapy of different types of cancer. However, a possible role of ER stress and GRP78 in endometrial cancer has never been investigated.

Methods

Tissue specimens from normal and neoplastic endometrium were analyzed for the expression of the ER stress markers GRP78, ATF6 and CHOP by Real-Time RT-PCR. In addition, GRP78 protein expression and localization were evaluated by Western blot and immunohistochemistry, respectively. The effect of GRP78 knock down on cell growth of Ishikawa cells was analyzed by proliferation curve analysis.

Results

In this analysis, the expression levels of GRP78, ATF6 and CHOP mRNAs were significantly increased in specimens of endometrioid endometrial carcinomas. GRP78 and ATF6 protein expression levels were also increased in specimens of endometrial adenocarcinomas. GRP78 knock down caused a decrease of Ishikawa cells' growth.

Conclusions

The increased expression of ER stress markers in endometrioid endometrial carcinomas suggests a role for ER stress, the UPR and, possibly, GRP78 in endometrial cancer. Whether these mechanisms have a substantial function in the pathogenesis of malignant transformation of human endometrium is still under investigation in our laboratory.     

Calreticulin has opposing effects on the migration of human trophoblast and myometrial endothelial cells

Calreticulin is a calcium binding, endoplasmic reticulum resident protein best known for its roles in intracellular calcium homeostasis and the quality control processes of the endoplasmic reticulum. There is evidence for a range of activities for calreticulin outside the endoplasmic reticulum, including in the cytosol, on the surface of different cells types and in the extracellular matrix. Recent evidence indicates that human pregnancy is a condition of elevated circulating calreticulin. Calreticulin was increased in the plasma of women throughout pregnancy compared to the non-pregnant state. Calreticulin was also further increased during the hypertensive disorder of human pregnancy, pre-eclampsia. To clarify the roles of circulating calreticulin in pregnancy and pre-eclampsia, the aim of this study was to determine the effects of exogenous calreticulin on two cell types that are relevant to normal human pregnancy and to pre-eclampsia. Human primary myometrial microvascular endothelial cells (UtMVEC-Myo) and the human trophoblast cell line, HTR8/SVneo, were cultured with exogenous calreticulin at concentrations (2 μg/ml and 5 μg/ml) comparable to that measured in maternal blood. The higher concentration of calreticulin significantly increased the migration of the UtMVEC-Myo cells, but significantly reduced the migration of the HTR8/SVneo cells. In the presence of only FGF, FBS and antibiotics calreticulin at 5 μg/ml significantly reduced the number of UtMVEC-Myo cells during in vitro culture for 120 h. These results demonstrate that exogenous calreticulin can alter both HTR8/SVneo and UtMVEC-Myo cell functions in vitro at a (patho-) physiologically relevant concentration. Increased calreticulin may also contribute to altered functions of both cell types during pre-eclampsia.     

Electron microscopic study on the structure and the function of the granulosa cell in the human ovary--ultrastructure and 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) activity

The cytodifferentiation, subcellular steroidogenic sites in the granulosa cell of the developing follicle were investigated using electron microscopic cytochemistry. The follicular cell in the primordial follicle already had a few lipid droplets. In the secondary follicle, the granulosa cell had a round nucleus, rough endoplasmic reticulum, lipid droplets, Golgi apparatus, microfilament, rod-shaped mitochondria with lamellar cristae and a small amount of smooth endoplasmic reticulum. In particular, the granulosa cell in the preovulatory follicle considered to be a transitional form to the steroid-secreting cell was characteristic of rough endoplasmic reticulum, lipid droplets, mitochondria with lamellar or tubular cristae and moderately well developed smooth endoplasmic reticulum. On the other hand, the granulosa cell in the postovulatory follicle revealed a typical steroid-secreting activity showing abundant lipid droplets, round mitochondria with tubular or vesicular cristae, well developed smooth endoplasmic reticulum and lysosomes. Reaction products for 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) activity were localized on tubular or lamellar cristae and inner membrane of the mitochondria, and on the membrane of smooth endoplasmic reticulum in the granulosa cell of the preovulatory as well as of the postovulatory follicle. From these facts, it is suggested that the granulosa cell in the preovulatory follicle already has a steroid-secreting activity and might play an important role in human reproduction.     

TMED2/p24β1 is expressed in all gestational stages of human placentas and in choriocarcinoma cell lines

Members of the transmembrane emp24 domain (Tmed)/p24 family of proteins are required for transport of proteins between the endoplasmic reticulum and the Golgi. One member of this family, Tmed2/p24β1, is expressed during placental development in mice and its expression is required for normal development of the labyrinth layer. Although TMED2 is conserved in humans, little is known about its expression and function in human placenta. We examined TMED2 expression in human placenta between 5.5 and 40 weeks of gestation and showed that TMED2 is expressed in syncytiotrophoblast, cytotrophoblast, and stromal cells. We also found high levels of TMED2 expression in BeWo but not in JEG-3 choriocarcinoma cell line. We used the BeWo cell line to determine TMED2 subcellular localization in placental cells and show its co-localization with the endoplasmic reticulum Golgi intermediate compartment. Our findings show conservation of TMED2 expression in human placenta and suggest that this protein may also play a role during placental development in humans.     

Endoplasmic reticulum stress in the pathogenesis of early-onset pre-eclampsia

Recent data have provided molecular evidence of high levels of endoplasmic reticulum stress in non-laboured placentas from cases of early-onset pre-eclampsia. Endoplasmic reticulum stress is intricately linked to oxidative stress, and the two often share the same aetiology. In the case of pre-eclampsia this is likely to be placental malperfusion, secondary to deficient conversion of the spiral arteries. Endoplasmic reticulum stress activates a number of signalling pathways aimed at restoring homeostasis, but if these attempts fail then the apoptotic machinery may be activated. The potential consequences for placental development and function are numerous and diverse. Inhibition of protein synthesis results in lower levels of many kinases, growth factors and regulatory proteins involved in cell cycle control, and experiments in vitro reveal that endoplasmic reticulum stress slows cell proliferation. Chronic, low levels of stress during the second and third trimesters may therefore result in a growth restricted phenotype. Higher levels of endoplasmic reticulum stress lead to activation of pro-inflammatory pathways, a feature of pre-eclampsia that may contribute to maternal endothelial cell activation. These findings emphasise the complexity of cellular responses to stress, and the need to approach these in a holistic fashion when considering therapeutic interventions.     

炔诺酮对人早孕蜕膜和绒毛超微结构的影响

用炔诺酮（５ｍｇｑ８ｈ×５天）抗早孕后作人工流产，对蜕膜和绒毛的超微结构进行观察。结果显示绝大部分蜕膜和绒毛滋养细胞均发生不同程度的退变和坏死。蜕膜组织中大蜕膜细胞和绒毛合体滋养细胞变性坏死较重，而蜕膜颗粒细胞和细胞滋养细胞仅轻度变性。细胞退变的超微结构特征皆以线粒体肿胀和粗面内质网扩张为先导，继之，线粒体固缩伴高电子密度颗粒沉积，内质网不规则扩张，直至细胞全面崩解。本文就炔诺酮通过引起子宫局部缺血而导致蜕膜和绒毛滋养层细胞变性坏死的可能性进行了讨论。     

Association of <Emphasis Type="Italic">GRP78</Emphasis> promoter polymorphisms and serum GRP78 level with risk of asthenozoospermia

Purpose

The aim of this study was undertaken to investigate the association of 78-kDa glucose-regulated protein (GRP78) gene promoter polymorphisms with risk of asthenozoospermia (AZS) men. In addition, we performed association analysis between GRP78 promoter mutations and serum GRP78 level in asthenozoospermia.

Methods

The study population comprised 400 subjects with AZS patients and 400 healthy controls. We assessed GRP78 rs3216733, rs17840761, and rs17840762 polymorphisms by using Snapshot SNP genotyping assays; serum GRP78 level was measured by enzyme-linked immunosorbent assay (ELISA). Semen quality was assessed by computer-assisted semen analysis.

Results

We found that rs3216733 was associated with increased risk of AZS (Gd vs. dd: adjusted OR?=?1.42, 95% CI, 1.06–1.93, P =?0.020; Gd/GG vs. dd: adjusted OR?=?1.43, 95% CI, 1.08–1.91, P =?0.013; G vs. d adjusted OR?=?1.26, 95% CI, 1.03–1.56, P =?0.027). The haplotype analyses showed the frequency of G-C-C haplotype was significantly higher in AZS (P =?0.026). The percentage of progressive motility sperm was lower in the asthenozoospermic men with Gd and Gd/GG genotypes than dd genotype (P =?0.003). Moreover, the serum GRP78 levels were significantly lower in rs3216733 Gd/GG genotypes compared with the dd genotype (P <?0.001).

Conclusion

Our findings suggest that rs3216733 Gd/GG genotypes contribute to poor sperm motility, probably by decreasing the level of GRP78.

     

Expression and intracytoplasmic distribution of staufen and calreticulin in maturing human oocytes

Purpose

In this study we hypothesized that the mRNA vector Staufen mediates RNA relocalization during meiotic maturation, and by virtue of its interactions with endoplasmic reticulum, provides a possible mechanism by which protein synthesis is regulated.

Methods

We assessed the expression of staufen (STAU) and calreticulin (CALR), the latter adopted as a marker of the endoplasmic reticulum, in human oocytes at different stages of maturation: GV, metaphase MI and MII. Oocytes were subjected to polymerase chain reaction in order to investigate the expression of STAU and CALR. The corresponding protein products were identified by immunofluorescence and confocal laser scanning microscopy.

Results

STAU and CALR were constantly expressed and selectively localized during oocyte maturation. At the GV stage the both proteins displayed a dispersed distribution localization throughout the cytoplasm. Progressing to the MII stage, STAU tended to compartmentalize towards the cortical area of the oocyte clustering in granules of larger sizes. At the MII stage, CALR assumed a pattern reminiscent and possibly coincident with the position of the meiotic spindle.

Conclusions

The changing pattern of STAU distribution during meiotic maturation of human oocytes implicates a novel mechanism for the regulation of protein synthesis based on mRNA localization. Moreover, the unique disposition of CALR at the MII spindle uncovers a physical interaction with endoplasmic reticulum that may mediate cytoskeletal remodelling during oocyte maturation.