帕罗西汀对慢性不可预见温和刺激的抑郁症大鼠抑郁行为的影响及其机制

目的探讨帕罗西汀对慢性不可预见温和刺激(Chronic unpredicted mild stress,CUMS)的抑郁症大鼠抑郁行为的影响及其机制。方法将SD大鼠随机分为正常对照组(NG)、模型组(MG)、帕罗西汀模型组(PMG)及帕罗西汀对照组(PNG),MG组和PMG组采用孤养结合CUMS方式复制大鼠抑郁模型,每天PMG组和PNG组灌胃盐酸帕罗西汀1.8 mg/kg,NG组和MG组灌胃等体积的5%CMC-Na溶液。通过高架十字迷宫试验和糖水偏好试验评价大鼠的抑郁行为;采用常规生物化学方法测定大鼠大脑皮层丙二醛(Malonaldehyde,MDA)含量及超氧化物歧化酶(Superoxide dismutase,SOD)和过氧化氢酶(Catalase,CAT)活性;RT-PCR检测海马5-羟色胺转运体(5-Hydroxy-tryptamine transporter,5-HTT)和去甲肾上腺素转运体(Noradrenaline transporter,NET)基因mRNA的转录水平。结果与NG组相比,MG组大鼠进入开放臂的次数和停留时间显著减少(P<0.01或P<0.001),而在封闭臂停留的时间明显延长(P<0.01);糖水偏好百分率显著下降(P<0.001);大脑皮层MDA含量显著升高(P<0.01),SOD和CAT活性显著降低(P<0.05);海马5-HTT和脑桥NET基因mRNA的转录水平均显著降低(P<0.001)。帕罗西汀能明显抑制CUMS诱导的上述改变(P<0.05),而对正常大鼠无显著影响(P<0.05)。结论帕罗西汀能明显改善CUMS所致的大鼠抑郁行为,其机制与增强机体抗氧化应激能力、上调海马5-HTT和脑桥NET基因mRNA的转录水平有关。     

川芎嗪对慢性脑缺血小鼠认知功能障碍及海马星形胶质细胞胶质原纤维蛋白表达的影响

目的探讨川芎嗪(tetramethylpyrazine,TMP)对慢性脑缺血小鼠认知功能障碍及海马星形胶质细胞胶质原纤维蛋白(glial fibrillary acidic protein,GFAP)表达的影响。方法采用改良双侧颈总动脉结扎术建立小鼠慢性脑缺血模型,经腹腔分别注射30和80 mg/kg的TMP注射液(即TMP低、高剂量组),每组10只,另设假手术组(不结扎),模型组和假手术组腹腔注射等量生理盐水。各组均在术后24 h开始给药,每日1次,连续8周。Morris水迷宫试验检测小鼠空间学习和记忆能力;黄嘌呤氧化酶法检测小鼠海马组织中的超氧化物歧化酶(superoxidedismutase,SOD)含量,硫代巴比妥酸(TBA)法检测丙二醛(malonaldehyde,MDA)含量,双抗体两步ELISA法检测肿瘤坏死因子-α(tumor necrosis factorα,TNF-α)及白介素-1β(interleukin-1β,IL-1β)含量;免疫组织化学染色法及Western blot法检测小鼠海马CA1区GFAP的表达水平。结果与模型组比较,TMP低、高剂量组小鼠在Morris水迷宫定位航行试验中的逃避潜伏期和游泳路程均明显缩短(P<0.05),空间探索试验中穿越原平台的次数增多(P<0.05);小鼠海马组织中SOD含量明显增加(P<0.05),MDA、TNF-α及IL-1β含量明显降低(P<0.05);IOD值明显下降(P<0.05),GFAP表达水平明显下降(P<0.05)。结论 TMP可改善慢性脑缺血小鼠认知功能障碍,其机制可能是增强抗脂质氧化能力,抑制星形胶质细胞增生活化,减少GFAP的表达,减轻炎症反应,从而降低对海马组织的损害。     

T-钙黏着蛋白与碱性成纤维细胞生长因子在人子宫肌瘤中的表达及其相关性

目的探讨T-钙黏着蛋白(T-cadherin)与碱性成纤维细胞生长因子(basic fibro blast growth factor,bFGF)在人子宫肌瘤中的表达及其相关性,以探讨二者在子宫肌瘤发生、发展过程中的作用。方法收集2011年9～12月间经重庆医科大学附属第一医院诊断为子宫肌瘤并行手术治疗,术后病理报告确诊为子宫肌瘤的患者50例,取其子宫肌瘤组织(A组)及同源正常子宫肌层组织(B组),同期收集经该院诊断为良性疾病并行手术治疗,术后病理报告确诊未患子宫肌瘤的10名患者正常子宫肌层组织作为对照组(C组)。50例子宫肌瘤患者根据术前彩色多普勒血流显像(Color Doppler Flow Imaging,CDFI)和激素水平进一步分组比较。采用SP免疫组化法检测子宫组织中T-cadherin和bFGF蛋白的定位,Western blot和RT-PCR法分别检测子宫组织中T-cadherin和bFGF蛋白的表达水平及基因mRNA转录水平,并分析二者与CDFI分级和激素分期的相关性。结果 A组T-cadherin主要定位于肌瘤细胞膜,bFGF主要定位于肌瘤细胞浆;A组子宫组织中T-cadherin和bFGF基因mRNA的转录水平及蛋白的表达水平均明显高于B组和C组(P<0.05),且二者明显呈正相关(P<0.01);T-cadherin和bFGF基因mRNA的转录水平及蛋白的表达水平均随CDFI等级的升高而增强(P<0.05或P<0.01)。结论 T-cadherin和bFGF在子宫肌瘤组织中高表达,提示二者在子宫肌瘤的发生、发展过程中起促进作用。     

过氧化物酶-4与胃癌发生发展的相关性

目的分析过氧化物酶-4(peroxidase-4,Prx4)与胃癌发生发展的相关性。方法利用甲基硝基亚硝基胍(N-methyl-N′-nitro-N-nitrosoguanidine,MNNG)诱导正常胃黏膜细胞GES-1构建癌变细胞模型,通过细胞形态、增殖率、迁移能力及集落形成能力的改变,确定MNNG最适浓度及最适诱变时间;经划痕试验、MTT法、集落形成试验、Western blot法和RT-PCR法进一步检测Prx4与胃黏膜上皮细胞恶性转化过程及转化细胞发展过程的相关性。结果MNNG最适浓度为8×10~(-5) mol/L,最适诱变时间为16 h。细胞恶性转化过程中呈现出细胞相对增殖率、迁移能力、集落形成能力整体升高的趋势;Prx4蛋白表达水平在0～16 h逐渐升高,16～24 h有所下降,而此时Prx4基因mRNA转录水平明显升高。转化细胞发展过程中呈现出细胞相对增殖率、迁移能力、集落形成能力整体逐渐升高的趋势;随着培养时间的增加,Prx4蛋白表达水平逐渐降低,Prx4基因m RNA转录水平无明显变化;但培养24 h时,恶性转化细胞mRNA基因转录水平显著高于正常胃黏膜细胞和胃腺癌细胞(P 0. 01)。结论正常胃黏膜细胞GES-1诱变16 h时已基本发生转化。细胞水平上,Prx4在转化过程中高表达,因此,Prx4主要参与并促进细胞转化过程。     

miR-34a过表达对小鼠脑皮质神经干细胞中巢蛋白表达的影响

目的探讨miR-34a(microRNA-34a)过表达对小鼠脑皮质神经干细胞(Neutral stem cell,NSCs)标志物巢蛋白(Nestin)表达的影响。方法通过神经球(Neurosphere)形成试验原代培养ICR胎鼠脑皮质NSCs,在脂质体2000的介导下分别转染miR-34a模拟物(mmu-miR-34a mimics)及其阴性对照(mmu-miR-34a control),另设脂质体对照组(仅转染脂质体)及空白对照组,转染48 h后,采用real time RT-PCR检测各组细胞中miR-34a的表达水平及Nestin基因mRNA的转录水平,Western blot检测Nestin蛋白的表达水平。结果 miR-34a模拟物转染后,显著上调了miR-34a在NSCs中的表达水平(P<0.01);miR-34a的过表达显著下调了NSCs中Nestin基因mRNA转录及蛋白的表达水平(P均<0.01)。结论外源性过表达miR-34a可下调NSCs中Nestin基因mRNA的转录水平及蛋白的表达水平,为NSCs的增殖、分化调控的研究提供了新的理论依据。     

姜黄素对睡眠剥夺小鼠学习记忆力的影响

目的探讨姜黄素(Curcumin)对睡眠剥夺(sleep deprived,SD)小鼠学习记忆力的影响。方法将50只C57雄性小鼠随机分为正常睡眠组、睡眠剥夺模型组和姜黄素低、中、高剂量组。采用改良多平台水环境法进行睡眠剥夺,姜黄素低、中、高剂量组分别于24、48及72 h经小鼠腹腔注射给药,剂量分别为5、10、20 mg/kg,正常睡眠组及睡眠剥夺模型组小鼠在相同时间给予腹腔注射等体积的生理盐水。每天给药1 h后经Morris水迷宫试验测试各组小鼠的学习记忆力;睡眠剥夺72 h后,检测小鼠海马组织中的超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)、丙二醛(malonaldehyde,MDA)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)的含量,Western blot法检测TNF-α的表达水平。结果与睡眠剥夺模型组比较,姜黄素各剂量组小鼠在Morris水迷宫定位航行试验中逃避潜伏期和游泳路程均明显缩短(P0.05),空间探索试验中穿越平台次数明显增多(P0.05);小鼠海马组织中SOD、GSH-Px含量明显增加(P0.05),MDA、TNF-α含量明显降低(P0.05);Western blot法结果表明,TNF-α的表达量明显下降(P0.05)。结论姜黄素可改善睡眠剥夺小鼠学习记忆力,其机制可能是减少自由基堆积,增强抗氧化能力,减少炎症因子TNF-α的产生。     

远志不同炮制品对东莨菪碱模型小鼠模型学习记忆的影响

目的:研究远志不同炮制品对东莨菪碱致小鼠痴呆模型学习记忆的影响。方法:采用腹腔注射氢溴酸东莨菪碱的方法制备小鼠痴呆模型,灌胃给予远志的不同炮制品,采用Morris水迷宫和Y迷宫评价远志不同炮制品对小鼠认知能力的影响,同时测定小鼠大脑皮层和海马区乙酰胆碱酯酶(Ach E)的活性。结果:远志不同炮制品均能够缩短小鼠水迷宫平台训练实验的潜伏期,增加空间探索实验中在目标象限的时间比和穿越平台位置次数,增加Y迷宫实验中正确反应次数,降低大脑皮层和海马区Ach E的活性。制远志在上述行为学指标方面的效果显著优于生远志。结论:制远志在神经保护作用方面的药效优于生远志。     

Apg-2基因沉默对BaF3-MIGR1及BaF3-P210细胞增殖的影响

目的探讨Apg-2基因沉默对pMIGR1空载体感染的BaF3-MIGR1细胞及稳定表达Bcr-Abl融合基因的BaF3-P210细胞增殖的影响,为进一步研究Apg-2在Bcr-Abl阳性的CML细胞中的作用奠定基础。方法针对Apg-2基因609～629、845～865和2 110～2 130核苷酸合成3条shRNA序列Hspa41、Hspa42、Hspa43,同时合成阴性对照序列HspaHK,电穿孔转染BaF3-MIGR1和BaF3-P210细胞,经G418筛选稳定抑制细胞株,RT-PCR和Western blot检测细胞中Apg-2基因mRNA的转录水平及蛋白的表达水平;Am-blue法检测细胞增殖;甲基纤维素法检测细胞克隆形成能力;流式细胞技术检测细胞周期的变化。结果转染的3条shRNA质粒中,shRNA-Hspa42的干扰效果最佳。Apg-2表达抑制后,BaF3-P210细胞的增殖与克隆形成能力均明显下降(P<0.05),处于G1期细胞的百分率明显升高(P<0.05),处于S期的细胞百分率明显下降(P<0.05);而BaF3-MIGR1细胞的增殖与克隆形成能力均明显增强(P<0.05),处于S期的细胞百分率明显升高(P<0.05)。结论干扰Apg-2基因的表达可抑制Bcr-Abl阳性细胞BaF3-P210的增殖,而对Bcr-Abl阴性细胞BaF3-MIGR1的增殖起促进作用。     

酶法处理短棒状杆菌对荷瘤鼠脾细胞免疫功能的影响

目的探讨酶法处理短棒状杆菌(Enzyme-digested Corynebacterium parvum product,ECPP)对荷瘤鼠脾淋巴细胞免疫功能的影响。方法将NIH小鼠随机分为5组:生理盐水对照组(NS)、荷瘤对照组(CK)、阳性对照组(CPP)、低剂量ECPP组(ECPPⅠ,500μg/ml ECPP)和高剂量ECPP组(ECPPⅡ,1 000μg/ml ECPP)。除NS组经腹腔注射0.2 ml 0.9%NaCl外,其他4组小鼠均经腹腔注射0.2 ml艾氏腹水瘤(Ehrlich ascites carcinoma,EAC)细胞悬液(5.0×106个/ml),接种次日,每组小鼠腹腔注射相应药物(注射体积均为0.25 ml),每次间隔1 d,连续5次,停药次日,颈椎脱臼处死小鼠,检测腹水量;3H-TdR法检测脾淋巴细胞转化能力;流式细胞术分析T淋巴细胞亚群及NK细胞活性;RT-PCR检测脾淋巴细胞中IFNγ、TNF-α基因mRNA的转录水平。结果与CK组相比,各给药组均能明显降低小鼠腹水量(P<0.01),CPP组和ECPPⅡ组间差异无统计学意义(P>0.05),ECPPⅡ组降低腹水的能力明显高于ECPPⅠ组(P<0.01);与NS、CK及ECPPⅠ组相比,ECPPⅡ组可明显提高T、B淋巴细胞的转化能力,增加脾CD4+、CD8+及NK细胞数量(P<0.01),而与CPP组比较,差异无统计学意义(P>0.05);与NS、CK和ECPPⅠ组比较,ECPPⅡ组IFNγ、TNF-α基因mRNA转录水平明显提高(P<0.01),与CPP组比较,差异无统计学意义(P>0.05)。结论 ECPP能显著提高荷瘤鼠脾细胞的免疫功能。     

霉酚酸酯对小鼠肺纤维化组织中转化生长因子-β1表达的影响

目的探讨霉酚酸酯(mycophenolate mofetil,MMF)对博莱霉素(bleomycin,BLM)诱导的小鼠肺纤维化组织中转化生长因子-β1(transforming growth factor-β1,TGF-β1)表达的影响。方法将C57BL/6小鼠随机分为6组:正常对照组、MMF对照组、BLM模型组、MMF低(20 mg/kg)、中(60 mg/kg)、高(100 mg/kg)剂量干预组,每组6只。BLM模型组和MMF 3个干预组经气管注入BLM(6 mg/kg),正常对照组和MMF对照组注入等量无菌生理盐水;次日按MMF对照组和MMF干预低、中、高剂量组小鼠体重计算MMF给药量,灌胃小鼠,每日1次,连续14 d,正常对照组和BLM模型组用等体积的双蒸水灌胃。灌胃第16天采集小鼠肺脏标本,经HE、Masson染色,从组织形态学上观察肺组织纤维化情况并进行Aschcroft评分;RT-PCR法检测小鼠肺组织中TGF-β1基因mRNA的转录水平;Western blot法检测小鼠肺组织中TGF-β1蛋白的表达水平。结果 BLM诱导的小鼠肺纤维化改变显著,Ashcroft评分较正常对照组显著增高(P<0.01),表明小鼠肺纤维化模型构建成功;MMF高剂量干预组肺组织损伤减轻,炎细胞浸润及胶原沉积减少,Ashcroft评分显著降低(P=0.000)。MMF高剂量干预组与BLM模型组比较,TGF-β1基因mRNA的转录水平及蛋白的表达水平均明显减低(P<0.05);而MMF低、中剂量干预组与BLM模型组之间、MMF对照组与正常对照组之间,差异均无统计学意义(P>0.05)。结论高剂量的MMF(100 mg/kg)可抑制BLM诱导的肺纤维化小鼠肺组织中TGF-β1基因mRNA的转录水平及蛋白表达水平,有望成为治疗肺纤维化的理想药物。     

妊娠期大鼠大量摄入酒精对子代糖代谢的影响及其机制

目的观察妊娠期大鼠大量摄入酒精对子代出生时及成年期糖代谢的影响,并探讨其机制。方法Wistard孕鼠酒精灌胃4g/(kg.d)至分娩前为酒精组,对照组给予等体积蒸馏水。每组子代鼠在出生1d及13周龄时,测定血糖、血浆胰岛素和抵抗素及脂肪组织抵抗素、瘦素mRNA转录水平。子代鼠13周龄时进行腹腔葡萄糖耐量试验。RT-PCR检测脂肪组织瘦素、抵抗素mRNA转录水平。结果与对照组比较,摄入酒精孕鼠的新生鼠出生时体重明显降低,血糖升高,血浆胰岛素含量降低。13周龄时酒精组血糖与对照组相比差异无显著意义,但血浆胰岛素明显高于对照组;葡萄糖耐量减低,葡萄糖及胰岛素曲线下面积明显增加。血浆抵抗素含量增加,酒精组新生鼠及13周龄子代鼠脂肪组织中抵抗素mRNA转录水平均显著增加,而酒精组新生鼠脂肪组织瘦素mRNA转录水平降低,13周龄子代鼠瘦素mRNA转录水平与对照组相比差异无显著意义。结论孕鼠大量摄入酒精引起子代出生后至成年期糖代谢改变可能与抵抗素增加有关。     

Silver Nanoparticles Impair Cognitive Functions and Modify the Hippocampal Level of Neurotransmitters in a Coating-Dependent Manner

Due to their potent antibacterial properties, silver nanoparticles (AgNPs) are widely used in industry and medicine. However, they can cross the brain–blood barrier, posing a risk to the brain and its functions. In our previous study, we demonstrated that oral administration of bovine serum albumin (BSA)-coated AgNPs caused an impairment in spatial memory in a dose-independent manner. In this study, we evaluated the effects of AgNPs coating material on cognition, spatial memory functioning, and neurotransmitter levels in rat hippocampus. AgNPs coated with BSA (AgNPs(BSA)), polyethylene glycol (AgNPs(PEG)), or citrate (AgNPs(Cit)) or silver ions (Ag⁺) were orally administered at a dose of 0.5 mg/kg b.w. to male Wistar rats for a period of 28 days, while the control (Ctrl) rats received 0.2 mL of water. The acquisition and maintenance of spatial memory related to place avoidance were assessed using the active allothetic place avoidance task, in which rats from AgNPs(BSA), AgNPs(PEG), and Ag⁺ groups performed worse than the Ctrl rats. In the retrieval test assessing long-term memory, only rats from AgNPs(Cit) and Ctrl groups showed memory maintenance. The analysis of neurotransmitter levels indicated that the ratio between serotonin and dopamine concentration was disturbed in the AgNPs(BSA) rats. Furthermore, treatment with AgNPs or Ag⁺ resulted in the induction of peripheral inflammation, which was reflected by the alterations in the levels of serum inflammatory mediators. In conclusion, depending on the coating material used for their stabilization, AgNPs induced changes in memory functioning and concentration of neurotransmitters.     

Color memory in children

The methods of simultaneous and memory color matching have been studied for a set of five Munsell color samples by 50 children, 25 boys and 25 girls (ranging in age from 9 to 11 years). By comparison between this group and one of 50 young adult observers, we can deduce the following: (a) In children, as in young adults, the mean CIELAB total color difference, ΔE*_ab, in simultaneous color matching is lower than the ΔE*_ab by memory color matching. (b) Children matched reference test worse than young adults for orange, bluish green (only boys and men) and yellow green (only girls and women). (c) While men remember, independently of age and delay time, violet reference test worse than women (P = 0.02), boys remember, independently of delay time, reference test worse than girls for orange (P = 0.026) and pink (P = 0.049). (d) In short‐term memory, boys remember the reference test better than girls for bluish green (P = 0.022); girls remember yellow green reference test worse than women (P = 0.034). (e) Chroma is the perceptual color attribute that best explains sex differences, although that depends upon the reference color test considered. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 372–380, 2008     

Tocotrienol Rich Fraction Reverses Age-Related Deficits in Spatial Learning and Memory in Aged Rats

Little is known about the effect of vitamin E on brain function. Therefore, in this study we evaluated the effect of tocotrienol rich fraction (TRF) on behavioral impairment and oxidative stress in aged rats. Thirty-six male Wistar rats (young: 3-months-old; aged: 21-months-old) were treated with either the control (olive oil) or TRF (200 mg/kg) for 3 months. Behavioral studies were performed using the open field test and Morris water maze (MWM) task. Blood was taken for assessment of DNA damage, plasma malondialdehyde (MDA) and vitamin E, and erythrocyte antioxidant enzyme activity. Brains were also collected to measure vitamin E levels. Results showed that aged rats exhibited reduced exploratory activity, enhanced anxiety and decreased spatial learning and memory compared with young rats. DNA damage and plasma MDA were increased, and vitamin E levels in plasma and brain were reduced in aged rats. Aged rats supplemented with TRF showed a markedly reduced level of anxiety, improved spatial learning and memory, reduced amount and severity of DNA damage, a reduced level of MDA, and increased levels of antioxidant enzyme activity and plasma/brain vitamin E compared with age-matched controls. In conclusion, TRF supplementation reverses spatial learning and memory decline and decreases oxidative stress in aged rats.     

Huperzine A Ameliorates Cognitive Deficits in Streptozotocin-Induced Diabetic Rats

The present study was designed to probe the effects of Huperzine A (HupA) on diabetes-associated cognitive decline (DACD) using a streptozotocin (STZ)-injected rat model. Diabetic rats were treated with HupA (0.05 and 0.1 mg/kg) for seven weeks. Memory functions were evaluated by the water maze test. Nissl staining was selected for detecting neuronal loss. Protein and mRNA levels of brain-derived neurotrophic factor (BDNF) were analyzed by ELISA and real-time PCR, respectively. The activities of choline acetylase (ChAT), Acetylcholinesterase (AChE), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), NF-κB p65 unit, TNF-α, IL-1β, IL-6 and caspase-3 were measured using corresponding kits. After seven weeks, diabetic rats exhibited remarkable reductions in: body weight, percentage of time spent in target quadrant, number of times crossing the platform, ChAT and BDNF levels, SOD, GSH-Px and CAT accompanied with increases in neuronal damage, plasma glucose levels, escape latency, mean path length, AChE, MDA level as well as CAT, NF-κB p65 unit, TNF-α, IL-1β, IL-6 and caspase-3 in cerebral cortex and hippocampus. Supplementation with HupA significantly and dose-dependently reversed the corresponding values in diabetes. It is concluded that HupA ameliorates DACD via modulating BDNF, oxidative stress, inflammation and apoptosis.     

c-Jun氨基末端激酶在邻苯二甲酸二(2-乙基)己酯诱导的尿道下裂大鼠阴茎组织中的表达

目的研究c-Jun氨基末端激酶(c-Jun N-terminal kinase,JNK)在邻苯二甲酸二(2-乙基)己酯[di(-2-ethyl-hexyl)phthalate,DEHP]诱导的尿道下裂大鼠阴茎组织中的表达变化,探讨尿道下裂发生的机制。方法将孕12 d(gestation day,GD12)的SD孕鼠随机分为2组:实验组[将DEHP溶于1.5 ml大豆油中灌胃大鼠,750 mg/(kg.d)]和对照组(以1.5 ml大豆油灌胃大鼠),每组20只,自GD12～GD19连续每天定时给药1次。各组分别取10只孕鼠正常分娩,雄性仔鼠出生后30 d,计数每窝产雄性活仔数,称量体重,并测量肛门生殖器距离(anogenital distance,AGD),逐个检查雄鼠的阴茎弯曲度和尿道开口部位,判断有无尿道下裂;其余孕鼠在怀孕第20天行剖宫产取出胎鼠,采用实时定量PCR(qPCR)和免疫组化法分别检测雄性胎鼠阴茎组织中JNK1和JNK2 mRNA和蛋白的表达水平。结果雄性仔鼠出生后30 d,实验组与对照组比较,每窝产雄性活仔数、雄性仔鼠的体重及AGD均有明显减少或缩短(P均<0.001);实验组尿道下裂发生率约为30.6%。与对照组比较,实验组胎鼠阴茎组织中JNK1和JNK2mRNA的水平明显增加(P<0.05),磷酸化JNK1和JNK2蛋白的表达水平有增加的趋势。结论 DEHP诱导的先天性尿道下裂可能与胎鼠阴茎组织中JNK通路异常表达有关。     

Aversive Learning Deficits and Depressive-Like Behaviors Are Accompanied by an Increase in Oxidative Stress in a Rat Model of Fetal Alcohol Spectrum Disorders: The Protective Effect of Rapamycin

Fetal alcohol spectrum disorders (FASDs) are one of the most common consequences of ethanol exposure during pregnancy. In adulthood, these disorders can be manifested by learning and memory deficits and depressive-like behavior. Ethanol-induced oxidative stress may be one of the factors that induces FASD development. The mammalian target of the Rapamycin (mTOR) signaling pathway that acts via two distinct multiprotein complexes, mTORC1 and mTORC2, can affect oxidative stress. We investigated whether mTOR-dependent or mTOR-independent mechanisms are engaged in this phenomenon. Thus, Rapamycin—a selective inhibitor of mTORC1, Torin-2—a non-selective mTORC1/mTORC2 inhibitor, and FK-506—a drug that impacts oxidative stress in an mTOR-independent manner were used. Behavioral tests were performed in adult (PND60-65) rats using a passive avoidance (PA) task (aversive learning and memory) and forced swimming test (FST) (depressive-like behaviors). In addition, the biochemical parameters of oxidative stress, such as lipid peroxidation (LPO), as well as apurinic/apyrimidinic (AP)-sites were determined in the hippocampus and prefrontal cortex in adult (PND65) rats. The rat FASD model was induced by intragastric ethanol (5 g/kg/day) administration at postnatal day (PND)4–9 (an equivalent to the third trimester of human pregnancy). All substances (3 mg/kg) were given 30 min before ethanol. Our results show that neonatal ethanol exposure leads to deficits in context-dependent fear learning and depressive-like behavior in adult rats that were associated with increased oxidative stress parameters in the hippocampus and prefrontal cortex. Because these effects were completely reversed by Rapamycin, an mTORC1 inhibitor, this outcome suggests its usefulness as a preventive therapy in disorders connected with prenatal ethanol exposure.     

The Effect of Different Intensities of Treadmill Exercise on Cognitive Function Deficit Following a Severe Controlled Cortical Impact in Rats

Exercise has been proposed for the treatment of traumatic brain injury (TBI). However, the proper intensity of exercise in the early phase following a severe TBI is largely unknown. To compare two different treadmill exercise intensities on the cognitive function following a severe TBI in its early phase, rats experienced a controlled cortical impact (CCI) and were forced to treadmill exercise for 14 days. The results revealed that the rats in the low intensity exercise group had a shorter latency to locate a platform and a significantly better improvement in spatial memory in the Morris water maze (MWM) compared to the control group (p < 0.05). The high intensity exercise group showed a longer latency and a mild improvement in spatial memory compared to the control group rats in the MWM; however, this difference was not statistically significant (p > 0.05). The brain-derived neurotrophic factor (BDNF) and p-CREB protein levels in the contralateral hippocampus were increased significantly in the low intensity exercise group. Our results suggest that 2 weeks of low intensity of treadmill exercise is beneficial for improving cognitive function and increasing hippocampal BDNF expression after a severe TBI in its early phase.     

Postnatal Smoke Exposure Further Increases the Hepatic Nicotine Metabolism in Prenatally Smoke Exposed Male Offspring and Is Linked with Aberrant Cyp2a5 Methylation

Prenatal smoke exposure (PreSE) is a risk factor for nicotine dependence, which is further enhanced by postnatal smoke exposure (PostSE). One susceptibility gene to nicotine dependence is Cytochrome P450 (CYP) 2A6, an enzyme responsible for the conversion of nicotine to cotinine in the liver. Higher CYP2A6 activity is associated with nicotine dependence and could be regulated through DNA methylation. In this study we investigated whether PostSE further impaired PreSE-induced effects on nicotine metabolism, along with Cyp2a5, orthologue of CYP2A6, mRNA expression and DNA methylation. Using a mouse model where prenatally smoke-exposed adult offspring were exposed to cigarette smoke for 3 months, enzyme activity, mRNA levels, and promoter methylation of hepatic Cyp2a5 were evaluated. We found that in male offspring, PostSE increased PreSE-induced cotinine levels and Cyp2a5 mRNA expression. In addition, both PostSE and PreSE changed Cyp2a5 DNA methylation in male groups. PreSE however decreased cotinine levels whereas it had no effect on Cyp2a5 mRNA expression or methylation. These adverse outcomes of PreSE and PostSE were most prominent in males. When considered in the context of the human health aspects, the combined effect of prenatal and adolescent smoke exposure could lead to an accelerated risk for nicotine dependence later in life.