The Impact of Oxytocin Gene Knockout on Sexual Behavior and Gene Expression Related to Neuroendocrine Systems in the Brain of Female Mice

Social relations are built and maintained from the interaction among individuals. The oxytocin (OT), vasopressin (VP), estrogen, dopamine, and their receptors are involved in the modulation of sexual behavior in females. This study aimed to analyze the impact of OT gene knockout (OTKO) on sexual behavior and the gene expression of oxytocin (OTR), estrogen alpha (ERα), estrogen beta (ERβ), vasopressin (V_1aR), and dopamine (D₂R) receptors in the olfactory bulb (OB), prefrontal cortex (PFC), hippocampus (HPC), and hypothalamus (HPT), as well as in the synthesis of VP in the HPT of female mice. Wild-type (WT) littermates were used for comparisons. The _CDNAs were synthesized by polymerase chain reaction and the gene expression was calculated with the 2^?ΔΔCt formula. Our results showed that the absence of OT caused an increase in the frequency and duration of non-receptive postures and a decrease in receptive postures in the OTKO. OTKO females showed a significant decrease in the gene expression of OTR in the HPC, V_1aR in the HPT, and ERα and ERβ in the PFC. There was no significant difference in the gene expression of D₂R of OTKO. However, OTKO showed an increased gene expression of V_1aR in the HPC. There is no significant difference in VP mRNA synthesis in the HPT between OTKO and WT. Our findings demonstrate that the absence of OT leads to significant changes in the expression of the studied genes (OTR, ERα, ERβ, V_1aR), and these changes may contribute to the decreased sexual behavior observed in OTKO females.     

葡萄胎中MBD2表达及其相关基因甲基化芯片研究

用Real-time RT-PCR、Western blot和免疫组织化学方法分别检测了去甲基化酶MBD2(methyl-CpG-binding domain 2,MBD2)在完全型葡萄胎(complete hydatidiform mole,CHM)和正常早期妊娠绒毛中的表达,用甲基化DNA免疫沉淀MeDIP(methylated DNA immunoprecipitation)-甲基化芯片分析完全型葡萄胎和正常早期妊娠绒毛中相关基因的甲基化情况,用生物信息学分析筛选了差异甲基化基因并进行功能分类。MBD2的mRNA在完全型葡萄胎中的表达明显高于正常早期妊娠绒毛(P=0.0083),Western blot(P=0.0005)和免疫组织化学(P=0.0091)检测到MBD2蛋白表达与Real-time RT-PCR结果一致。结果显示MBD2在完全型葡萄胎中的表达显著高于正常早期妊娠绒毛组织(P<0.01),与正常早期妊娠绒毛组织相比较,完全型葡萄胎组织中相对有89个基因发生了去甲基化,其中85个基因可被映射到基因组图谱中,MBD2在完全型葡萄胎中的高表达及部分基因的去甲基化可能在完全型葡萄胎的发生中扮演了重...     

滋养层细胞侵袭相关基因表达谱分析

分离收集正常妊娠第8～12周的细胞滋养层细胞和绒毛外滋养层细胞,提取细胞总RNA,制备cRNA探针并与AffymetrixU133plus2.0基因芯片进行杂交,获得正常细胞滋养层细胞和绒毛外滋养层细胞基因表达谱芯片。经计算机分析共筛选到1318个差异表达基因,其中上调基因813个,下调505个。所有差异表达基因按GeneOntoloty功能分类标准进行了功能检索。为胚胎发育早期绒毛外滋养层细胞侵袭的基因调控机制的研究提供了实验基础。     

Early and Late Gene Changes in MPTP Mice Model of Parkinson's Disease Employing cDNA Microarray

Recently, we reported specific brain gene expression changes in the chronic MPTP model in the late stage of degeneration, employing cDNA expression array, which indicate a domino cascade of events involved in neuronal cell death. In an attempt to elucidate early gene expression profile in the region of the substantia nigra (SN) and the striatum of acute MPTP-treated mice (3–24 h), we elected a restricted number of genes affected by the long-term MPTP treatment, and their expression was examined. Specifically, we detected alterations in the expression of genes implicated in oxidative-stress, inflammatory processes, signal transduction and glutamate toxicity. These pro-toxic genes appear to be compensated by the elevated expression in trophic factors and antioxidant defenses, which are also activated by short exposure to MPTP. The time course of these gene expression changes indicates the importance of investigating the early gene cascade of events occurring prior to late nigrostriatal dopamine neuronal cell death.     

Changes in Gene Expression Associated with FTO Overexpression in Mice

Single nucleotide polymorphisms in the first intron of the fat-mass-and-obesity-related gene FTO are associated with increased body weight and adiposity. Increased expression of FTO is likely underlying this obesity phenotype, as mice with two additional copies of Fto (FTO-4 mice) exhibit increased adiposity and are hyperphagic. FTO is a demethylase of single stranded DNA and RNA, and one of its targets is the m6A modification in RNA, which might play a role in the regulation of gene expression. In this study, we aimed to examine the changes in gene expression that occur in FTO-4 mice in order to gain more insight into the underlying mechanisms by which FTO influences body weight and adiposity. Our results indicate an upregulation of anabolic pathways and a downregulation of catabolic pathways in FTO-4 mice. Interestingly, although genes involved in methylation were differentially regulated in skeletal muscle of FTO-4 mice, no effect of FTO overexpression on m6A methylation of total mRNA was detected.     

cDNA Microarray Analysis of Gene Expression in the Cerebral Cortex and Hippocampus of BALB/c Mice Subjected to Chronic Mild Stress

Depressive disorders are devastating metal illness that can lead to deterioration in the social and occupational functioning of affected individuals. The etiology and pathophysiology of depression remain unknown. Present study was performed to better understand the underlying causes of depression. An experimental animal depression was induced in male BALB/c mice subjected to a chronic mild stress (CMS) procedure involving different stressor for consecutive 4 weeks. A cDNA microarray was employed to study the effects of CMS on the gene expression in cerebral cortex and hippocampus. 4-week CMS caused a significant reduction of 2% sucrose consumption. Morris water maze procedure showed impairment in cognitive function in stressed mice. Results of microarray showed that there were 102 and 60 genes were markedly affected by CMS treatment in cerebral cortex and hippocampus regions, respectively, including DNA damage/repair-related enzymes, anti-oxidant enzyme, and cyclin and cyclin-dependent kinase (CDK). These findings suggest that multiple biochemical effects play an important role the etiology of depression.     

cDNA Microarray Analysis of Changes in Gene Expression Associated with MPP+ Toxicity in SH-SY5Y Cells

cDNA microarray analysis of 1-methyl-4-phenyl-pyridinium (MPP⁺) toxicity (1 mM, 72 h) in undifferentiated SH-SY5Y cells identified 48 genes that displayed a signal intensity greater than the mean of all differentially expressed genes and a two-fold or greater difference in normalized expression. RT-PCR analysis of a subset of genes showed that c-Myc and RNA-binding protein 3 (RMB3) expression decreased by 50% after 72 h of exposure to MPP⁺ (1 mM) but did not change after 72 h of exposure to 6-hydroxydopamine (25 M), rotenone (50 nM), and hydrogen peroxide (600 M). Exposure of retinoic acid (RA)-differentiated SH-SY5Y cells to MPP⁺ (1 mM, 72 h) also resulted in a decrease in RMB3 expression and an increase in GADD153 expression. In contrast, c-Myc expression was slightly increased in RA-differentiated cells. Collectively, these data provide new insights into the molecular mechanisms of MPP⁺ toxicity and show that MPP⁺ can elicit distinct patterns of gene expression in undifferentiated and RA-differentiated SH-SY5Y cells.     

ApoE基因缺失幼龄小鼠动脉粥样硬化相关基因的时序表达研究

利用RT-PCR技术检测apoE基因缺失(apoE-/-小鼠在1、2和3月龄3个年龄段主动脉以及14天、1、2和3月龄4个年龄段肝脏中动脉粥样硬化(atherosclerosis,AS)重要相关基因的时序表达特点,并通过血清牛化检测结合主动脉根部病理形态学特征的分析,探讨AS重要相关基因时序表达特点与AS早期病变的关系.在主动脉检测的9条AS相关基因中,apoE-/-与野生型(WT)小鼠相比,1、2和3月龄时IL-1β的mRNA表达水平均显著上调.1月龄时VCAM-1、IKB和TGF-β,2月龄时PDGF-α和CD36,3月龄时TNF-α和MM2的mRNA表达水平均显著上调,其他年龄段无显著变化.在肝脏检测的2条AS相关基因中,C反应蛋白(CRP)的mRNA表达水平在14天到2月龄时无显著变化,3月龄时显著上调.NF-kB在各年龄段apoE-/-小鼠主动脉和肝脏中的基因表达量与同龄WT小鼠相比均无显著差异.不同年龄段的apoE-/-小鼠血清TC、TG和LDL-C水平均明显高于同龄WT小鼠.2月龄apoE-/-小鼠主动脉内膜出现散在的脂质沉积,并随年龄增长逐渐加重.上述结果显示,时序表达上调的AS重要相关基因构成了以NF-kB为核心的复杂调控网络,它们之间相互作用,共同参与慢性炎症过程,在apoE-/-小鼠AS的早期发生发展中发挥重要作用.     

不同代次牛成肌细胞的诱导分化及相关基因的表达分析

利用初生荷斯坦牛的成肌细胞,在不同代次以含体积分数为2%马血清的DMEM进行诱导分化,在之后0、2、4、6、8、10 d观察细胞的形态变化并收集细胞提取总RNA,检测成肌相关基因的表达情况,为进一步研究牛肌肉发生过程及相关基因的表达调控提供依据。同时利用实时荧光定量PCR分别检测肌性相关基因MyoD(生肌决定因子)、MyoG(肌细胞生成素)以及非肌性相关基因A-FABP(脂肪细胞型脂肪酸结合蛋白)表达水平的变化。研究表明：①各代细胞在诱导培养4 d后开始有肌管形成,其后越来越多,8 d时达高峰。②成肌细胞向成熟肌细胞分化过程中,MyoD、MyoG、A-FABP基因都呈先上升然后下降的趋势。③高代次成肌细胞比低代次细胞增殖慢,而且在诱导分化后,肌管的数目明显变少; MyoD、MyoG、A-FABP随着代次的升高而下降。故推断MyoD、MyoG以及A-FABP基因会在成肌分化开始后的不同阶段被激活,从而发挥不同的调控作用,而且随着传代次数的增加成肌细胞的分化能力减弱。