脑胶质瘤EZH2基因的表达分析

目的探讨脑胶质瘤果蝇zeste基因增强子同源物2（EZH2）蛋白的表达变化。方法选取2010年5月至2011年12月手术切除的胶质瘤组织标本83例,其中2008年WHO分级Ⅰ级15例,Ⅱ级20,Ⅲ级26例,Ⅳ级22例;术前均未接受放疗或化疗。另外,收集30例颅脑损伤内减压手术切除的无肿瘤脑组织作为对照。采用实时荧光定量PCR法检测EZH2 m RNA表达。根据EZH2 m RNA表达水平分为高表达组（EZH2 m RNA≥0.3,48例）和低表达组（EZH2 m RNA〈0.3,35例）,分析两组术后生存期。结果胶质瘤组织EZH2 m RNA表达水平明显高于对照组（P〈0.01）,高级别胶质瘤（WHOⅢ、Ⅳ级）组织EZH2 m RNA表达水平明显高于低级别胶质瘤（WHOⅠ、Ⅱ级）组织（P〈0.01）。低表达组患者术后生存期较高表达组显著延长（P〈0.01）。结论脑胶质瘤组织EZH2 m RNA呈高表达,且其表达水平与病理分级具有相关性。     

人脑胶质瘤中CD133的表达及其意义

目的 探讨CD133 mRNA在人脑胶质瘤组织中的表达及其与病理分级的相关性.方法 用半定量逆转录聚合酶链反应法(RT-PCR)对43例胶质瘤患者、16例正常脑组织标本(均为急性颅脑损伤患者行内减压术切除的脑组织)进行CD133 mRNA检测.结果 (1)43例胶质瘤组织中CD133 mRNA表达全部呈阳性,而16例正常脑组织标本中仅有1例CD133 mRNA表达呈弱阳性.病例组和正常对照组CD133 mRNA的阳性率分别为100%和6.25%.病例组和对照组CD133 mRNA表达阳性率差异有统计学意义(P＜0.01).(2)在病例组中,参照1993年WHO分级标准分为Ⅰ级、Ⅱ级、Ⅲ级、Ⅳ级组,计算分组的标本CD133 mRNA与β-actin mRNA灰度比值.Ⅰ级和Ⅲ、Ⅳ级之间差异有统计学意义(P＜0.01),Ⅲ、Ⅳ级之间CD133 mRNA表达均高于Ⅰ级;Ⅱ级和Ⅲ、Ⅳ级之间差异有统计学意义(P＜0.01),Ⅲ、Ⅳ级之间CD133 mRNA表达均高于Ⅱ级.(3)相关性分析:CD133 mRNA表达量与胶质瘤病理分级呈正相关性(r=0.987,P＜0.001).结论 检测胶质瘤组织中CD133 mRNA的表达可用于胶质瘤患者的诊断及恶性程度和预后的判断.     

脑胶质瘤组织中胸腺嘧啶核苷激酶1的表达和意义及其与细胞增殖抗原Ki67表达的关系

目的 研究脑胶质瘤组织中胸腺嘧啶核苷激酶1(TK1)的表达和意义,以及其与细胞增殖抗原Ki67表达的关系.方法 202例脑胶质瘤患者,经病理检查进行脑胶质瘤病理分级及组织类型分型.采用免疫组化染色法检测脑胶质瘤组织中TK1和Ki67的表达.比较不同级别及类型患者脑胶质瘤组织中TK1表达的阳性率;分析TK1与Ki67表达的关系.结果 本组患者脑胶质瘤按WHO分级:Ⅰ级12例,Ⅱ级85例,Ⅲ级60例,Ⅳ级45例;组织类型分型:少突胶质细胞瘤28例,星形胶质细胞瘤174例.本组患者TK1阳性119例(58.9％);其中良性组(WHO Ⅰ级)患者无TK1阳性,低度恶性组(WHO Ⅱ级)阳性31例(36.5％),高度恶性组(WHO Ⅲ、Ⅳ级)阳性88例(83.8％);三组间TK1阳性率比较差异均有统计学意义(P ＜0.05 ～0.001).星形胶质细胞瘤及复发患者的TK1阳性率分别显著高于少突胶质细胞瘤和初发的患者(均P＜0.05).TK1与Ki67的表达水平呈正相关(r=0.711,P＜0.01).结论 恶性程度高、星形胶质细胞瘤及复发的脑胶质瘤患者瘤组织中TK1的表达增高;提示TK1表达可作为脑胶质瘤病理分级、分型及复发的重要参考指标.TK1与Ki67正相关,提示TK1亦可反映脑胶质瘤细胞的增殖情况.     

Smad2基因在人脑胶质瘤的表达及其临床意义

目的 探讨Smad2基因在人脑胶质瘤组织中的表达情况,与细胞增殖指数Ki-67及患者生存期的关系.方法 对80例人脑胶质瘤组织标本,用免疫组化SP法检测Smad2、Ki -67的蛋白表达,逆转录聚合酶链反应法( RT - PCR)测定Smad2 mRNA的转录水平.Smad2蛋白表达情况与患者生存期的关系用Kaplan -Meier生存曲线表示,并采用log - rank方法分析.结果 (1) Smad2蛋白在高级别胶质瘤(Ⅲ级和Ⅳ级)中表达水平较低级别胶质瘤(Ⅱ级)明显增高(P ＜0.001).(2)Smad2 mRNA在高级别胶质瘤(Ⅲ级和Ⅳ级)中转录水平较低级别胶质瘤(Ⅱ级)增高(P＜0.05).(3)Smad2蛋白阳性表达与Ki -67阳性表达呈正相关(r=0.812,P＜0.001).(4)将所有患者分为Smad2高表达组和低表达组,两组间生存率差异有统计学意义(P＜0.05).结论 Smad2的转录和蛋白表达水平在恶性胶质瘤中显著增高,检测Smad2表达水平有利于脑胶质瘤的恶性程度判断及对患者预后的评估.     

lncRNA NEAT1在人脑胶质瘤的表达变化及其与病人预后的关系

目的 探讨长链非编码核糖核酸（lncRNA）NEAT1在人脑胶质瘤中的表达水平及其临床意义。方法 收集武汉大学人民医院神经外科2008年4月到2013年4月收治的65例脑胶质瘤标本及同期因颅脑手术切除的正常脑组织27例。65例胶质瘤中,WHO Ⅰ~Ⅱ级26例,Ⅲ~Ⅳ级39例。根据胶质瘤组织lncRNA NEAT1表达水平,将65例胶质瘤分成lncRNA NEAT1高表达组（n=38）和低表达组（n=27）。应用RT-PCR检测lncRNA NEAT1的表达水平,用Kaplan-Meier法进行生存分析,用多因素Cox比例风险回归模型分析lncRNA NEAT1的表达水平与病人预后关系。结果 胶质瘤组织lncRNA NEAT1的表达水平（2.893±0.296）显著高于正常人脑组织（1.000±0.297;P=0.001）。WHO Ⅰ~Ⅱ级胶质瘤lncRNA NEAT1的表达水平（2.160±0.270）显著低于WHO Ⅲ~Ⅳ级胶质瘤（3.627±0.312;P=0.005）。lncRNA NEAT1高表达组病人术后生存期明显缩短（P=0.033）,术后5年累积生存率显著低于lncRNA NEAT1低表达组（P=0.033）。lncRNA NEAT1表达水平高、病理级别高、KPS评分<80分以及复发时间<3个月是影响胶质瘤病人术后预后的独立危险因素（P<0.05）。结论 lncRNA NEAT1在人脑胶质瘤组织中表达水平明显增高,其表达水平与胶质瘤病人预后显著相关。     

反义AKT2 RNA抑制U251胶质瘤细胞生长的体内外研究

目的 研究反义AKT2RNA对U251人脑胶质瘤细胞在体内外的生长抑制效用。方法 将逆转录病毒pLXSN为载体的反义AKT2构建体转染U251人脑胶质瘤细胞系，应用蛋白印记确定基因转染前后AKT2的表达水平。流式细胞法与Matrigel基质生长实验评价肿瘤细胞转染前后的增殖活性。进一步应用裸鼠皮下荷瘤模型观察脂质体介导pLXSN、pLXSN-AS-AKT2基因治疗对U251细胞生长抑制作用。在28d的观察期内定期测量皮下肿瘤体积，对肿瘤标本应用免疫组化的方法进行AKT2和胶质纤维酸性蛋白（GFAP）表达比较。结果 脂质体介导pLXSN-AS-AKT2可显著抑制U251细胞AKT2表达。与对照组和pLXSN转染组比较，细胞周期分析结果表明AK—AKT2转染组进入S期的细胞数减少了8．5％～8．9％，而进入G0＋G1期细胞则增加了7．9％～8．6％。Matrigel基质生长实验显示对照组和pLXSN转染组细胞呈正常形态贴壁生长，而AS～AKT2转染组细胞不能贴壁生长，呈团块状簇集生长。裸鼠皮下荷瘤模型实验显示pLXSN-AS-AKT2显著抑制皮下肿瘤生长，组织病理学分析显示AS-AKT2转染组AKT2表达下降而GFAP表达上调。结论 体内外实验证明反义AKT2方法在抗胶质瘤增殖方面作用重要，AKT2可作为基因治疗胶质瘤的优选靶标。     

胶质瘤中miR-134的表达及意义

目的 探讨miR-134在人脑胶质瘤组织和胶质瘤细胞系U87、U251中的表达及意义.方法 采用实时荧光定量PCR检测11例正常脑组织、42例不同级别脑胶质瘤组织、人脑胶质瘤细胞系U87和U251中miR-134的表达情况.结果 与正常脑组织相比,miR-134在不同级别胶质瘤中的表达均明显下降(均P＜0.05).WHOⅢ～Ⅳ级胶质瘤组织中miR-134表达明显低于WHO Ⅰ～Ⅱ级(P＜0.05).与正常脑组织相比,miR-134在胶质瘤细胞系U87、U251中的表达亦显著降低(均P＜0.05).结论 miR-134在胶质瘤中呈低表达,提示其可能参与胶质瘤的发生、发展.     

神经胶质瘤组织及外周血中ERCC1的表达水平与替莫唑胺化疗效果的相关性研究

目的 探讨神经胶质瘤组织及外周血中切除修复交叉互补基因1(excision repair cross-complementing gene 1, ERCC1)的表达水平与替莫唑胺化疗效果的相关性。方法 选择本院就诊并进行外科手术治疗的神经胶质瘤患者67例,其中WHO Ⅱ级21例,WHO Ⅲ级26例,WHO Ⅳ级20例; 化疗前取患者肿瘤组织以及外周血样本,利用实时荧光定量PCR法检测肿瘤组织及外周血中ERCC1基因的表达水平; 所有患者术后均口服替莫唑胺化疗,结合患者临床病理生理因素、患者的总生存期(OS)和疾病进展时间(TTP)进行相关性分析。结果 ERCC1基因在肿瘤组织及外周血中均有表达,且两者表达水平呈正相关(r=0.621,P<0.001),外周血及肿瘤组织中ERCC1低表达水平的患者可以获得更高的有效率,更长的OS和无进展生存期(PFS)(P<0.001)。Cox回归分析发现外周血和肿瘤组织中ERCC1的表达水平是影响OS和PFS的独立因素。结论 肿瘤组织及外周血中ERCC1的低表达水平患者更能从替莫唑胺化疗中获益,ERCC1的表达水平可以作为替莫唑胺疗效预判的指标之一。     

人脑胶质瘤EPO与CD105表达及意义

目的 探讨人脑胶质瘤组织促红细胞生成素（EPO）和CD105的表达变化及其意义。方法 收集2002~2008年人脑胶质瘤标本152例,其中WHO分级Ⅰ级4例,Ⅱ级32例,Ⅲ级68 例,Ⅳ级48例;取同期颅脑损伤内减压术切除正常脑组织20例为对照,采用免疫组化染色分析EPO及CD105表达。收集2005~2008年人脑胶质瘤标本胶质瘤17例（WHO Ⅱ级6例,Ⅲ~Ⅳ级11例）,正常对照5例,采用实时荧光定量PCR检测EPO mRNA表达变化。术后随访截止2010年4月23日,应用Kaplan-Meier生存曲线分析高级别（Ⅲ~Ⅳ级）胶质瘤生存曲线。结果 胶质瘤EPO表达阳性率（60.5%,92/152）明显高于正常脑组织（10%,2/20;P<0.001）,胶质瘤EPO表达强度与病理分级呈正相关（rs=0.368,P<0.001）。EPO表达阳性组CD105阳性率明显高于阴性组（P<0.05）,EPO高表达组明显高于低表达组（P<0.05）。Ⅱ级胶质瘤组EPO mRNA表达水平明显高于正常组与Ⅲ~Ⅳ级胶质瘤组（P<0.05）。对于高级别（WHO Ⅲ~Ⅳ级）胶质瘤,EPO低表达组中位生存时间为12个月,高表达组为36个月;EPO低表达组累积生存率明显低于高表达组（P<0.05）。结论 人脑胶质瘤EPO蛋白的表达与病理级别及新生血管正相关;WHO Ⅱ级胶质瘤EPO mRNA在转录水平已上调;WHO Ⅲ~Ⅳ级组胶质瘤EPO表达高者生存期长。     

铁死亡调控基因亚精胺/精胺N1-乙酰基转移酶1在脑胶质瘤中的 表达及临床意义

目的 探讨铁死亡调控基因亚精胺/ 精胺N1- 乙酰基转移酶1（SAT1）在脑胶质瘤患者中的 表达趋势及临床意义。方法 纳入中国脑胶质瘤基因组图谱计划（CGGA,http：//www.cgga.org.cn/）及美 国癌症基因组图谱计划（TCGA, http：//www.cancergenome.nih.gov/）数据库中3 批次共1 720 例（CGGA-325 组、CGGA-693 组及TCGA组分别为325、693、702 例）脑胶质瘤患者的临床资料及其胶质瘤组织样本表 达谱数据,分析SAT1 基因的表达趋势及与患者病理、分子病理指标、预后等因素的相关关系。应用细 胞模型研究SAT1 基因在脑胶质瘤中的生物学功能。采用Kaplan-Meier生存曲线比较SAT1 基因表达量 不同的脑胶质瘤患者的生存差异;应用受试者工作特征（ROC）曲线评估SAT1 对脑胶质瘤患者1 年和 3 年总生存率的预测作用。结果 在脑胶质瘤患者样本中,SAT1 在异柠檬酸脱氢酶（IDH）野生型胶质 母细胞瘤中表达水平最高,在IDH突变联合1p19q 缺失的低级别胶质瘤中表达水平最低（CGGA-325 组、 CGGA-693 组及TCGA 组患者中,均P＜ 0.001）。在世界卫生组织（WHO）Ⅲ级及Ⅳ级的患者中,SAT1 高 表达的患者预后更差（不同数据库、不同级别SAT1 高表达及低表达患者的中位生存期分别为：CGGA- 325 组WHO Ⅲ级患者,485 d 和1 321 d,P＜ 0.05;CGGA-325 组WHO Ⅳ级患者, 286 d 和493 d,P＜ 0.05; CGGA-693 组WHO Ⅲ级患者, 836 d 和2 982 d,P＜ 0.05;CGGA-693 组WHO Ⅳ级患者,356 d 和459 d, P＜ 0.05;TCGA 组WHO Ⅲ级患者, 31.57 个月和114 个月,P＜ 0.05;TCGA 组WHO Ⅳ级患者, 11.24 个 月和13.77 个月,P ＜ 0.05）。CGGA-325 组患者中,应用ROC 曲线评估SAT1 对患者1 年和3 年生存的预 测能力,其曲线下面积（AUC）分别为0.725、0.793;在CGGA-693 组数据中,其AUC 分别为0.615、0.671; 在TCGA 组中,其AUC 分别为0.791、0.808（均P＜ 0.001）;在细胞模型中,下调SAT1基因表达,可抑制胶 质瘤细胞增殖率（两种细胞系作用24 h 及48 h 后, 均P＜ 0.05）。结论 SAT1基因与脑胶质瘤患者级别、 分子亚型、预后等显著相关,可能通过激活肿瘤细胞增殖发挥作用。     

Infectious inflammation of the CNS involves activation of mitogen-activated protein kinase and AKT proteins in CSF in humans

Abstract The mitogen-activated protein kinases (MAPKs) and the AKT are interacting proteins that serve as transmitters of numerous extracellular signals to their intracellular targets, thereby regulating many cellular processes, such as proliferation, differentiation, development or stress responses. Whereas a large amount of information about the MAPKs/AKT participation in biological processes is available, less is known about their role in human diseases. We postulated that the MAPKs/AKT could be involved in inflammatory processes of the central nervous system (CNS) in humans and we investigated the CSF of 12 patients with viral infection of the CNS for the presence of the distinct components of these cascades. The cerebrospinal fluid (CSF) of 18 individuals who underwent a lumbar puncture for diagnostic purposes served as controls. Six patients with inflammatory disease of the CNS revealed the presence of activated ERK. In five patients p38MAPK was detected, in three in its activated form. The activity of AKT could be demonstrated in four patients. JNK was not found. None of the control patients showed the presence of MAPK enzymes. The mean CSF cellularity was higher in MAPK-positive than in MAPKnegative patients. There was no difference in mean age or gender between the patients and controls, or between the MAPK- and AKT-positive or -negative patients. Our work demonstrates that the MAPK and AKT cascades might participate in inflammatory processes of the CNS. As selective inhibitors of the MAPKs are available, their application in the future might reduce an inappropriate inflammatory response and thus limit brain damage in severe cases of meningoencephalitis.     

PI3K、AKT、PTEN在脑胶质瘤中的表达及其临床意义

目的 探讨磷脂酰肌醇3-激酶(phosphatidylinositol 3-kinase,PI3K)、苏氨酸蛋白激酶(serine-threonine kinase,AKT)、第10号染色体缺失的磷酸酶和张力蛋白同源物基因(phosphatase and tensin homolog deleted from chromosome 10,PTEN)在脑胶质瘤中的表达情况及其临床意义。方法 本院收治的43例脑胶质瘤患者为观察组,30例其他脑部疾病患者为对照组; 根据病理分级分为低级别组23例和高级别组20例; 计算各组PI3K、AKT、PTEN表达阳性率。结果 观察组PI3K、AKT阳性率显著高于对照组(P<0.05); 观察组PTEN阳性率显著低于对照组(P<0.05); 低级别组PI3K阳性率和AKT阳性率显著低于高级别组(P<0.05); 低级别组PTEN阳性率显著高于高级别组(P<0.05); Pearson相关性分析表明:PI3K与AKT呈显著正相关(r=0.882,P<0.05); PI3K、AKT与PTEN呈显著负相关(r=-0.753,-0.775,P<0.05)。结论 PI3K、AKT、PTEN可相互作用,能够反映脑胶质瘤病情进展。     

RNA干扰技术联合抑制AKT1和COX-2表达对U251胶质瘤细胞增殖的影响

目的 探讨应用RNA干扰(RNAi)技术抑制U251恶性胶质瘤细胞株AKT1和COX-2表达后,在体外对U251细胞增殖的抑制作用.方法 构建靶向AKT1和COX-2的RNAi重组腺病毒表达载体(rAd-A+C)转染至U251细胞.应用Realtime PCR检测AKT1和COX-2 mRNA水平的变化;应用Western blot检测AKT1和COX-2蛋白水平的变化,并对肿瘤细胞中相关功能蛋白的表达进行分析;应用MTr法和流式细胞术评价肿瘤细胞的增殖活性.结果 rAd-A+C可显著抑制U251细胞AKT1和COX-2的表达;与对照组和无义序列处理组(rAd-HK)比较,Western blot分析结果显示下游相关因子PCNA、Cyclin D1表达下降,而p53表达上调;细胞周期分析结果表明rAd-A+C处理组进入S期的细胞数较对照组减少了7.0%～7.8%,出现G0/G1期阻滞;MTT法分析显示rAd-A+C处理组细胞生长抑制率＞58%.结论 靶向AKT1和COX-2的RNAi技术可显著抑制U251细胞AKT1和COX-2表达,在体外对U251细胞增殖活性产生明显抑制作用.因此,RNAi重组腺病毒表达载体介导的基因治疗可成为胶质瘤靶向治疗的新策略.     

AKT1 Gene Polymorphisms and Obstetric Complications in the Patients with Schizophrenia

Objective

We performed a genetic association study with schizophrenic patients to investigate whether the V-akt murine thymoma viral oncogene homolog 1 (AKT1) gene plays a role in obstetric complications.

Methods

One-hundred-eighty patients with schizophrenia (male, 113; female, 67) were included. All patients fulfilled DSM-IV criteria for schizophrenia. Obstetric complications were measured by the Lewis scale. Prenatal and perinatal information was retrospectively collected from the patients'' mothers. We selected six single nucleotide polymorphisms (SNPs) for the AKT1 gene: SNP1 (rs3803300), SNP2 (rs1130214), SNP3 (rs3730358), SNP4 (rs 1130233), SNP5 (rs2494732), and SNPA (rs2498804). The genotype data were analyzed for an association with the Lewis total score in terms of allele, genotype, and haplotype distribution.

Results

The mean total Lewis scores were 1.30±1.61 for males and 1.54±1.87 for females. Higher total score tended to be correlated with an earlier age of onset of schizophrenia in females. In the total sample, no SNP was associated with obstetric complications. However, the additional analyses for male and female subgroups found a significant association between SNPA and SNP4 and Lewis score in females (p=0.02 for SNPA, p=0.04 for SNP4). The SNP5-SNPA haplotype showed a positive association with obstetric complications (p=0.03) in the female patient group.

Conclusion

We found an association between SNPs in the AKT1 gene and total Lewis score measuring obstetric complications in female patients with schizophrenia. Because these findings did not survive a correction for multiple testing, the significance should be interpreted carefully and replication studies are required.     

Inhibition of dystroglycan binding to laminin disrupts the PI3K/AKT pathway and survival signaling in muscle cells

Dystroglycan is a component of the dystrophin-glycoprotein complex (DGC) in muscle and a cell surface receptor for laminin. Numerous muscular dystrophies are the result of disruption of proteins comprising the DGC, but the underlying pathogenetic mechanisms are unknown. Because apoptosis is an early feature of muscular dystrophy in vivo, and perturbation of cell-extracellular matrix associations is known to induce apoptosis, we investigated the role of dystroglycan-laminin interactions in the propagation and maintenance of cell survival signals in muscle cells. We found that disrupting the interaction between alpha-dystroglycan and the extracellular matrix protein laminin induces apoptosis in muscle cells. This increase in apoptosis is mediated in part by caspase activation and can be blocked by a caspase-3 inhibitor. We demonstrate a role for the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway in muscle cell-survival signaling using a pharmacological inhibitor of PI3K. Treatment with this inhibitor resulted in decreased phosphorylation of AKT and its downstream effector glycogen synthase kinase (GSK)-3beta and induced apoptosis in muscle cell cultures. Disruption of dystroglycan-laminin interactions resulted in decreased phosphorylation of AKT and GSK-3beta. Furthermore, activation of AKT prior to the disruption of dystroglycan-laminin protected the muscle cells from the induction of apoptosis. These results support a role for the PI3K/AKT pathway in the propagation of cell-survival signals mediated by the DGC and provide new insight into the molecular pathogenesis associated with the development of muscular dystrophies.     

Association between AKT1 gene polymorphisms and depressive symptoms in the Chinese Han population with major depressive disorder

For this study, 461 Chinese Han patients with depressive disorder were recruited. The AKT1 genotype and allele distribution were determined by PCR amplification and direct sequencing. UNPHASED software was used to analyze associations between the 17-item Hamilton Depression Rating Scale, total score, four factors and the AKT1 rs2494746 and rs3001371 polymorphisms. The results indicate that there is a significant association between suicidal ideation and anxiety symptoms in depressed patients and the rs2494746 polymorphism. The other AKT1 polymorphism, rs3001371, was significantly associated with work and activities. Patients with the rs3001371-A allele had a significantly more severe illness compared to patients with the rs3001371-G allele. Thus, AKT1 polymorphisms appear to be associated with depression severity, anxiety symptoms, work and activities, and suicide attempts in patients with depressive disorder.     

The AKT1 gene is associated with attention and brain morphology in schizophrenia

Abstract

Objectives. A meta-analysis of the associations between genetic variants in the AKT1 gene and schizophrenia found that a single nucleotide polymorphism (SNP5; rs2494732) was associated with schizophrenia in Asian populations. Methods. In this study, we investigated the effects of this SNP on memory and attentional performance and brain structure using magnetic resonance imaging in a Japanese population (117 patients with schizophrenia and 189 healthy subjects). Results. The memory performance, particularly attention/concentration score, measured by the Wechsler Memory Scale-Revised in A carriers of SNP5, which was found to be enriched in patients with schizophrenia, was lower than that in individuals with the G/G genotype. We confirmed the association of the SNP with attentional performance using the Continuous Performance Test, which assessed sustained attention and vigilance of attentional function. Patients with A allele demonstrated lower attentional performance than patients with the G/G genotype. Patients with the A allele had smaller gray matter volumes in the right inferior parietal lobule related to attentional processes and in the frontostriatal region related to different SNPs in AKT1 than patients with the G/G genotype. Conclusions. Our results suggest that a genetic variant of AKT1 might be associated with attentional deficits and brain morphological vulnerability in patients with schizophrenia.     

Neuroprotection by PGE2 receptor EP1 inhibition involves the PTEN/AKT pathway

The prostanoid synthesizing enzyme cyclooxygenase-2 (COX-2) is involved in the mechanisms of cerebral ischemia, an effect mediated by prostaglandin E2 through activation of EP1 receptors. Thus, inhibition of EP1 receptors is neuroprotective in models of ischemic stroke, but the molecular mechanisms of the effect have not been fully elucidated. We used oxygen glucose deprivation (OGD) in hippocampal slices as an injury model to investigate whether the neuroprotection afforded by EP1 receptor inhibition involves the PI3K/AKT survival pathway. EP1 receptor inhibition with SC51089 or SC51322 reduced the hippocampal damage produced by ODG by 28 ± 2% and 32 ± 3%, respectively (p < 0.05). OGD induced a transient reduction of AKT activity that was partly counteracted by SC51089. LY294002 blocked the increase in phospho-AKT evoked by SC51089 and abolished the associated protective effect. The AKT activation induced by SC51089 was associated with phosphorylation of PTEN, the phosphatase that negatively regulates AKT. Furthermore, SC51089 attenuated the mitochondrial translocation of the proapoptotic protein BAD. These data indicate that EP1 receptor inhibition improves the survival of hippocampal slices by preventing the attenuation in AKT activity induced by OGD, and by reducing the mitochondrial translocation of BAD. The findings provide evidence for a link between EP1 receptors and the PI3K/AKT survival pathway and shed light on the molecular mechanisms of the prosurvival effect of EP1 receptor inhibition.     

Further evidence for association of variants in the AKT1 gene with schizophrenia in a sample of European sib-pair families.

BACKGROUND: Involvement of AKT signaling pathways in schizophrenia has been recently suggested, on the basis of several lines of evidence. In addition to impairment of protein-levels and phosphorylation levels in the pathway, association of DNA sequence variants in the AKT1 gene with schizophrenia has been detected in a family sample. METHODS: We investigated the reported association of DNA sequence variants in the AKT1 gene in a sample of 79 sib-pair families with schizophrenia using the five single nucleotide polymorphisms (SNPs) of the original study and two additional SNPs in the neighborhood of the SNP for which association had been reported. RESULTS: We obtained statistical significance for single markers (p = .002) and multilocus haplotypes (p = .0013) located in the same region as has been reported in the previous study. CONCLUSIONS: The replication of association of variants in the AKT1 gene in a family sample with similar ethnical background as in the original study adds further evidence for involvement of AKT1 in development of schizophrenic disorders.