PSYCH OpenIR  > 健康与遗传心理学研究室
大鼠可变产前应激及妊娠期补充乳酸菌对子代行为或前额叶生理影响的研究
其他题名The impact of repeated variable prenatal stress an gestational Lactobacillus helveticus supplement on thed offsbring rats' behavior or Phvsiology of the PFC
牛云霞
学位类型博士
导师金锋
2018-06
学位授予单位中国科学院研究生院
学位授予地点北京
学位专业认知神经科学
关键词产前应激 妊娠期补充乳酸菌 前脉冲抑制 生理指标 青春期 焦虑
摘要

  【研究背景】英国流行病学家David J. Barker博士很早就说过;“子宫可能比家庭更重要”。当代诸多的神经科学研究也告诉我们胎儿期的确是各种神经精神疾病最为易感的一个阶段。本研究将探究早期环境对子代生理或行为的影响。首先,己有不少研究指出产前应激是致使子代患许多神经精神疾病,比如精神分裂症、注意缺陷多动障碍、自闭症和物质使用障碍的重要风险因素。Markham和Koenig曾总结多个产前应激方式的动物模型用于研究不同的神经和精神疾病。然而,由于神经精神疾病在遗传和生理上的复杂性,几乎没有哪一种动物模型可以完全模拟这些疾病。另外,日前关于机体表面的“外环境”对机体影响的研究开始十分盛行,即机体所携带的微生物,尤其是肠道微生物。也有许多研究指出机体所携带的微生物同中枢神经系统的发生和发育有着密切的联系,其作用在生命的早期阶段尤为重要。益生元、益生菌和抗生素等是我们所熟知的可以有效改变机体所携带菌群的方法。乳酸杆菌是最重要的益生菌类型之一,且乳杆菌属广泛存在于人类身体的内外表面,比如整个消化道,在宿主健康中发挥着巨大作用。有些研究指出早期补充益生菌可降低儿童后期患神经精神障碍的风险,且产前补充益生菌和益生元的效果可能比婴儿期补充更有效。但是,关于妊娠期补充乳酸菌的安全性和有益性的研究还较少,其效用结果的呈现特点也不清楚。同时研究发现产前应激的影响具有性别特异性;青春期也是一个心理和生理的敏感期。而现有的动物实验研究多聚焦于成年期的雄性,关于雌性以及青春期阶段对象的研究较少,也更缺乏关于两种性别(雌性和雄性)和各个年龄阶段(比如青春期和成年期)的比较研究。
      [研究目的]本研究的主要目的是探究产前不利环境(可变产前应激)和产前有益因素(妊娠期补充乳酸菌)对子代的影响。在可变产前应激实验研究中,本研究采用了一个折中的策略,即仅将研究的焦点聚焦在大鼠可变产前应激对子代的生理和行为影响的结果和特点的分析上。本研究将检测大鼠前额叶对可变产前应激的应答,以及其对前额叶应答的性别(雌性和雄性)和年龄(青春期和成年期)差异的影响。另外,在妊娠期补充乳酸菌的实验中,本研究将探究妊娠期使用乳酸菌对子代行为是否有益或者有害,所呈现的特点,以及其对子代行为性别(雌性和雄性)和年龄(青春期和成年期)差异的影响。同时,本研究将比较正常条件下子代大鼠相应生理和行为的性别(雌性和雄性)和年龄(青春期和成年期)差异,以丰富相关研究成果。
      【研究方法】首先,由于人类妊娠中期是易患精神疾病的关键期,而大鼠妊娠期的最后一周(从妊娠的第14天到生产)约相当于人类的妊娠中期,所以可变产前应激的实施和乳酸菌补充均选择在大鼠妊娠期的最后一周。又由于前脉冲抑制与额叶执行功能密切相关,具有跨物种和跨时间的可比性,所以产前应激实验和妊娠期补充乳酸菌的实验均测定了子代大鼠惊反射的前脉冲抑制(PPI )。其次,在可变产前应激实验中,因为前额叶接收从其他所有皮层区域输入的信息,且在工作记忆、自我调节和目标导向的行为中有重要作用。前额叶是大脑中最后一个成熟的结构之一,在青春期和成年期之间的差异最大,且前额叶的发育也具有性别特异性。所以本部分研究重点关注对前额叶的分析。同时,研究发现产前应激可能会损害神经元、突触、免疫系统、HPA轴系统、5-HT和多巴胺系统。本研究用商用ELISA试剂盒检测了与前额叶密切相关或者易受产前应激影响的7个生理指标在前额叶中的含量,即脑源性神经营养因子(BDNF )、分化抗原簇68 C CD68 )、突触结合蛋白一1 ( Syt-1)、多巴胺(DA)和5-经色胺C 5-HT )、糖皮质激素受体(GR)和雌激素受体(ER)。再次,在妊娠期补充乳酸菌的实验中,由于本实验室以往研究证实瑞士乳杆菌NS8可提升高血氨大鼠的认知,改善慢性束缚应激大鼠的焦虑、抑郁和认知功能障碍症状。因此在妊娠期补充乳酸菌的实验中,本研究选择瑞士乳杆菌NS8。本部分研究用旷场实验和高架十字迷宫,两种最为常用的测定情绪的仪器,来检测子代的情绪。最后,使用方差分析法和相应的事后检验法,分析了相关生理、体重、脑重和行为数据;以及用非参数检验法分析了产仔量的数据。
      【研究结果】在可变产前应激实验研究中,主要有如下结果:C1)首先,可变产前应激提升了青春期阶段雌鼠和雄鼠的%PPI,提升了成年雌鼠的%PPI,而降低了成年雄鼠的%PPI;可变产前应激打破了雄鼠的%PPI随年龄增长而显著增长的趋势;可变产前应激打破了成年鼠中%PPI的性别差异,并没有打破青春期鼠中的这一差异。其次,可变产前应激升高了青春期阶段雌鼠前额叶中BDNF和CD68的含量,并打破了其随年龄增长而显著增长的趋势;可变产前应激升高了青春期雄鼠前额叶的Syt-1含量,降低了成年期雄鼠的Syt-1含量;可变产前应激打破了雄鼠前额叶的DA含量随年龄增长而增长的趋势;可变产前应激升高了成年期雄鼠前额叶的5-HT含量;可变产前应激没有显著改变ER和GR在所有组的大鼠前额叶中的含量。C2)在对照组中,%PPI和各个生理指标的年龄和性别差异主要呈现如下状况。首先,在年龄差异中,雌鼠的%PPI在青春期和成年期之间没有显著差异,雄鼠的%PPI呈现为青春期显著低于成年期。雌鼠和雄鼠前额叶中BDNF和CD68的含量都随年龄增长而显著增长;雄鼠前额叶中Syt-1, DA和5-HT的含量随着年龄的增长而显著增长,而雌鼠前额叶的Syt-1,DA和5-HT含量不随年龄变化而发生显著变化;GR不随年龄变化而发生显著变化;雌鼠前额叶的ER含量随着年龄的增长而显著增长,而雄鼠前额叶的ER含量不随年龄变化而发生显著变化。其次,在性别差异中,青春期阶段的%PPI无显著的性别差异,而在成年期时则是雄鼠显著高于雌鼠。BDNF , ER和GR在前额叶中的含量都没有显著性别差异;青春期和成年期大鼠前额叶的CD68含量,均是雄鼠都显著高于雌鼠;前额叶的Syt-1含量,呈现青春期雌鼠显著高于青春期雄鼠,而在成年期则无此差异;成年雄鼠前额叶的DA和5-HT含量显著高于成年雌鼠。C3) 68dB前脉冲刺激强度上的%PPI与前额叶的BDNF, CD68, Syt-1和ER含量都成显著正相关关系;与DA,  5-HT和GR含量的相关性不显著。
    在妊娠期补充乳酸菌的实验中,主要有如下结果:C1)妊娠期补充乳酸菌组的脑重量和对照组无显著差异;妊娠期补充乳酸菌组和对照组子代鼠的脑重量都随着年龄的增长而显著增长;妊娠期补充乳酸菌组和对照组子代鼠的脑重量,在20日龄、青春期和成年期,都呈现为雄性显著高于雌性。C2)妊娠期补充乳酸菌组子代大鼠的体重在51, 76和86日龄时显著低于对照组。各组的体重都随着年龄增长而显著增加。雄鼠51, 66, 76和86日龄的体重显著高于雌鼠,而28日龄的体重无此性别差异。C3)妊娠期补充乳酸菌对三种行为数据结果的影响如下:在高架十字迷宫测试中,妊娠期补充乳酸菌组开臂活动的相对时间显著高于对照组。在旷场实验中,妊娠期补充乳酸菌组在中心区活动的相对时间、中心区相对进入次数、中心区活动的相对距离显著高于对照组,在进入中心区的潜伏期的相对时间显著低于对照组。在前脉冲抑制测试中,妊娠期补充乳酸菌对%PPI的改变不显著,也没有显著改变%PPI的年龄和性别差异。C4)对照组中三种行为数据结果的年龄差异如下:在高架十字迷宫测试中,青春期大鼠开臂活动的相对时间显著高于成年期大鼠,闭臂进入的次数显著低于成年期大鼠。在旷场试验中,青春期大鼠的相对总静止时间显著高于成年期大鼠;青春期大鼠在中心区活动的相对时间显著高于成年期大鼠;青春期大鼠的总活动距离显著大于成年期大鼠。在前脉冲抑制测试中,成年期大鼠的%PPI显著高于青春期大鼠。 CS)对照组中三种行为数据结果的性别差异如下:在高架十字迷宫测试中,青春期雌鼠的开臂活动的相对时间显著高于青春期雄鼠。在旷场试验中,青春期雌鼠的相对总静止时间显著高于青春期雄鼠。在前脉冲抑制测试中,雄鼠的%PPI显著高于雌鼠。
      【结论】本研究发现,可变产前应激可能加速青春期阶段大鼠的前额叶的发育,从而导致前脉冲抑制和特定生理指标的年龄差异(青春期阶段和成年期阶段)和性别差异(雌性和雄性)的缩小,而且,这一加速效应可能具有性别差异;神经免疫系统可能在年龄和性别差异中起着重要作用;同神经发育密切相关的生理指标也与运动门控密切相关。本研究还发现,妊娠期补充NS8乳酸菌可能对子代具有一定抗焦虑作用,尤其是对青春期阶段的子代;且不会对情绪和前脉冲抑制的年龄差异(青春期阶段和成年期阶段)和性别差异(雌性和雄性)产生影响;而且,妊娠期补充NS8乳酸菌可能有助于减轻处于不健康生活方式子代的体重。

其他摘要

  Background: Dr. David J. Barker, a British epidemiologist, once said, "the uterus may be more important than the family.”Many contemporary neuroscientific studies have also told us that the fetal period is indeed the most susceptible stage of many kinds of neuropsychiatric disorders. Here we will explore the effects of the early environment on the neurophysiology and psychology of the offspring in rats.Prenatal stress is a risk for many kinds of neuropsychiatric disorders. Markham and Koenig have reported that many kinds of prenatally stressed animals are used to study different types of neurological and psychiatric diseases. However, due to the genetic and physiological complexity of neuropsychiatric disease, almost none of these animal models can fully address the problem of these types of diseases. In addition,the day before on the body surface of the "external environment" impact on body health research is very popular, in which the body is carried by microorganisms,especially intestinal microorganisms. Many studies have pointed out that the microorganisms carried by the body, mainly intestinal microbes, are involved to the occurrence and development of the central nervous system, especially in the early stage of life. Probiotic bacteria, prebiotics and antibiotics are well known methods that can effectively change the flora of the organism. Lactobacillus species are one of the most important types of probiotics. Genus Lactobacillus is also widely distributed on inner and outer surfaces of the human body and throughout the entire digestive tract,is also an essential member of gut microbiota which plays great role in host health. It has been reported that probiotic supplement in early life may reduce the risk of neuropsychiatric disorder development later in childhood. However, there are few studies on the safety and benefits of supplementation of lactic acid bacteria during pregnancy. At the same time, studies have been found that the effects of prenatal stress were sex specific; adolescence is a psychological and physiological sensitive period; however, most of the existing animal researches focus on adult males; there are lack of studies about females and adolescence, and there is also a lack of comparative research on two kinds of sex (female and male) and different ages (such as adolescence and adulthood).
    Objective: The main purpose of present study is to explore the effects of prenatal adverse factors (Variable repeated prenatal stress, PNS) and prenatal beneficial factors (Lactobacillus helveticus (L. helveticus) supplement during pregnancy, LAC) on the offspring in rats. In the first study, a compromise strategy is adopted, that is, the focus of the research is only focused on the results and characteristics of the PNS effects on offspring rats' physiology and behavior. We will detect the response of rat prefrontal cortex to PNS, and the sex (male and female) and age (adolescence and adulthood) differences. In the second study, it will explore the effects of gestational L. helveticus on the offspring rats' behavior. The subjects included two kinds of sexe (male and female) and two age stages (adolescence and adulthood), and which also investigated the sex and age differences. Meanwhile present study will compare the sex (male and female) and age (adolescence and adulthood) differences, in order to enrich the relevant research results.
    Methods: Because the last week of gestation (i.e. from gestational day 14 until delivery) in rats approximately coincides with the second trimester of gestation in humans, which is considered critical for vulnerability to psychiatric disorders. Both variable repeated prenatal stress (PNS) and gestational L. helveticus supplement (LAC)was administrated in the last week of rats' gestation. PPI (Prepulse Inhibition) is a robust phenomenon that is found across species and can be studied in both humans and animals with relative technical ease. Thus in the present study the prepulse inhibition was tested.
    In the first study, evidence showed that the PFC receives input from all other cortical regions and is very important in working memory and self-regulatory and goal-directed behaviours; the PFC is one of the last structures in the brain to mature;the differences in the PFC between the adolescent and adult brain are greatest; The development of the PFC is also sex-specific. So this part focused on the analysis of prefrontal cortex. Evidence also showed that prenatal stress could damage neurons,synapses, the immune system, the HPA system, the serotonin and dopamine systems.We tested the following physiological indices using commercially available ELISA kits, which are closely associated with the PFC or vulnerable to prenatal stress, i.e.Brain-derived neurotrophic factor (BDNF), Cluster of differentiation 68 (CD68),Synaptotagmin-1 (Syt-1), Dopamine (DA), 5-hydroxytryptamine (5-HT),Glucocorticoid receptors (GR) and Oestrogen receptors (ER).
    In the second study, L. helveticus strain NS8 has been shown to improve cognition in hyperammonemia rats, and improve chronic restraint stress-induced behavioral (anxiety and depression) and cognitive dysfunction. Thus L. helveticus strain NS8 will be administrated in this part. Then the open-field test (OFT) and the elevated-plus maze (EPM) were used to evaluate the offspring rats' emotion. Finally,the ANOVA and the corresponding post hoc test will be used in the data of body weight, brain weight, physiological indices, and behaviour; and nonparametric tests were used to analyze the data of litter size.
    Results: In the first study, the main results are as follows: (1) PNS significantly increased the percentage of prepulse inhibition (%PPI) of adolescent female and male rats, significantly increased %PPI in adult female rats, significantly decreased %PPI in adult male rats; PNS disturbed the significant increase of %PPI with age in male rats; PNS disturbed the significant sex difference in adult rats, not in adolescent rats.PNS significantly increased the content of BDNF and CD68 in the PFC in the adolescent female rats, and disturbed its significant increase with age; PNS did not significantly change the content of ER and GR in the PFC; PNS significantly increased the content of Syt-1 in the PFC in adolescent male rats and significantly decreased its content in adult male rats; PNS disturbed the significant increase of DA content with age in male rats; PNS significantly increased the content of 5-HT in PFC in adult male rats. (2) In the control group, the increase of %PPI with age was significant in male rats, not significant in female rats; %PPI in adult male rats was significantly higher than in adult females, and this sex difference was not significant in adolescent rats. And in the control group, the content of BDNF and CD68 in the PFC significantly increased with age in female and male rats; the contents of ER in the PFC significantly increased with age in female rats; the content of Syt-1,DA and 5-HT in the PFC significantly increased with age……

语种中文
文献类型学位论文
条目标识符http://ir.psych.ac.cn/handle/311026/26140
专题健康与遗传心理学研究室
作者单位中国科学院心理研究所
推荐引用方式
GB/T 7714
牛云霞. 大鼠可变产前应激及妊娠期补充乳酸菌对子代行为或前额叶生理影响的研究[D]. 北京. 中国科学院研究生院,2018.
条目包含的文件
文件名称/大小 文献类型 版本类型 开放类型 使用许可
牛云霞--博士学位论文 .pdf(8592KB)学位论文 限制开放CC BY-NC-SA浏览 请求全文
个性服务
推荐该条目
保存到收藏夹
查看访问统计
导出为Endnote文件
谷歌学术
谷歌学术中相似的文章
[牛云霞]的文章
百度学术
百度学术中相似的文章
[牛云霞]的文章
必应学术
必应学术中相似的文章
[牛云霞]的文章
相关权益政策
暂无数据
收藏/分享
文件名: 牛云霞--博士学位论文 .pdf
格式: Adobe PDF
所有评论 (0)
暂无评论
 

除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。