用磁共振成像技术探讨唾液酸对仔猪早期脑发育的影响

发布时间：2018-03-19 18:31

本文选题：仔猪脑发育　切入点：唾液酸　出处：《厦门大学》2014年硕士论文　论文类型：学位论文

【摘要】：唾液酸(Sialic acid, Sia)是自然界中以酰基化形式存在的神经氨酸衍生物的统称。唾液酸具有多种生物学功能,比如：促进细胞的增值、分化和参与识别；与病原微生物相互作用,参与免疫反应；促进神经系统的发育,易化记忆形成,提高学习能力。大脑发育的关键时期,进行干预可以对大脑造成远期的不可逆的影响。许多动物实验表明唾液酸可以对大脑发育、学习和记忆能力产生重要影响。仔猪因其发育和解剖与婴儿相似,适合做研究婴儿发育的动物模型。磁共振成像技术因其对软组织空间分辨率高、可用多种参数成像和对机体无辐射损伤等优点已广泛应用于脑代谢、脑结构和的脑功能定量研究中。本实验以新生仔猪为动物模型,通过在饮食中添加唾液酸,用磁共振成像及定量分析技术,探索唾液酸对仔猪脑结构发育的影响。平均体重为2kg的61头3日龄仔猪,随机分为4组：对照组(不额外添加N-乙酰神经氨酸,N=16)、实验组一(N-乙酰神经氨酸601.8mg/100g,N=15)、实验组二(乳糖结合的N-乙酰神经氨酸486.8mg/100g,N=14)和实验组三(酪蛋白结合的N-乙酰神经氨酸和乳糖结合的N-乙酰神经氨酸各占50%以及0.5g/L的乳铁蛋白,N-乙酰神经氨酸的总含量为439.1mg/100g,N=16),且保证相同遗传背景的仔猪不在同一组。仔猪在38日龄进行磁共振(nuclear magnetic resonance, NMR)扫描,第39日龄仔猪安乐死断头取脑。NMR扫描采集的数据包括：T1加权成像(T1-weighted imaging, T1WI), T2加权成像(T2-weighted imaging, T2WI),弥散张量成像(Diffusion Tensor Imaging, DTI)。对T1图像用基于体素的形态测量学(voxel based morphometry, VBM)方法分析组间灰质体积的差异：DTI图像上用于工划分感兴趣区(region of interest,ROI)的方法将胼胝体分成三部分,并测量胼胝体各部的各向异性分数(fractional anisotropy,FA)。统计方法：实验组一、实验组二和实验组三分别和对照组进行双样本T检验(Two-sample t-test),以探究唾液酸对仔猪大脑发育过程中结构的影响。实验结果：各实验组相对于对照组仔猪的体重、脑重和全脑体积的差异无统计学意义。经图像处理和统计分析,VBM的结果如下：实验组一较对照组灰质体积增加的区域有左侧背外侧运动皮层、左侧小脑小叶和左侧初级视觉皮层,灰质体积减少的区域有左侧上丘；实验组二较对照组灰质体积增加的区域有左侧躯体感觉皮层、左侧颞叶、左侧岛叶皮层、左侧海马旁回、右侧小脑小叶,体积减少的区域为前联合周围灰质、中央灰质、右侧屏状核、右侧丘脑背外侧核。实验组三较对照组灰质体积增加的区域有左侧丘脑,左侧海马旁回,灰质体积减少区域为小脑小叶。DTI的结果是,各实验组相对于对照组胼胝体三个区域的FA值的差异均无统计学意义。本实验得出以下结论：(1)唾液酸对仔猪的体重、脑重和脑体积的影响不显著,差异无统计学意义；(2)唾液酸对仔猪大脑发育有促进作用,并且不同存在形式的唾液酸对仔猪大脑发育的影响不同。其中实验组一的配方奶可以促进左侧躯体感觉皮层、左侧颞叶、左侧岛叶皮层、左侧海马旁回、右侧小脑小叶等皮层灰质的发育；实验组二的配方奶可以促进左侧躯体感觉皮层、左侧颞叶、左侧岛叶皮层、左侧海马旁回、右侧侧小脑小叶皮层的发育；实验组三的配方奶可以促进部分丘脑神经核团以及海马旁回的发育。(3)唾液酸对胼胝体的发育没有显著影响,差异无统计学意义。
[Abstract]:Sialic acid (Sialic acid Sia) is a general designation of neuraminic acid derivatives in the form of acylation in nature. Sialic acid has many biological functions, such as promoting cell proliferation, differentiation and identification of pathogenic microorganisms in; and interactions involved in the immune response; promote the development of the nervous system, facilitated the formation of memory, to improve the ability of learning. The critical period of brain development, intervention can cause long-term irreversible effects on the brain. Many animal experiments show that sialic acid can have an important impact on brain development, learning and memory ability. Because of the development of piglets and the anatomy and the baby is similar to that for studying infant animal model development. Magnetic resonance imaging because of its high spatial resolution of soft tissue, can use a variety of parameters of imaging and no radiation damage to the body and other advantages has been widely used in brain metabolism, brain structure and brain function. It can be used in quantitative research.
In this experiment, the animal model of newborn piglets, by adding sialic acid, using magnetic resonance imaging and quantitative analysis technology, and explore the effects of sialic acid on the development of baby pig structure.
The average weight of 3 day old piglets 2kg 61, were randomly divided into 4 groups: control group (add N- acetylneuraminic acid, no additional N=16), experimental group (N- acetylneuraminic acid 601.8mg/100g, N=15), experimental group two (N- acetylneuraminic acid 486.8mg/100g, lactose binding N=14) and the experimental group (three casein binding N- acetylneuraminic acid and lactose binding N- acetylneuraminic acid and 0.5g/L each accounted for 50% of total content of lactoferrin, N- acetylneuraminic acid 439.1mg/100g, N=16), and ensure that the same genetic background were not in the same group. Piglets underwent magnetic resonance at 38 days of age (nuclear magnetic resonance, NMR) scanning, thirty-ninth day old piglets euthanasia decapitated.NMR scan data collected include: T1 weighted imaging (T1-weighted imaging, T1WI), T2 (T2-weighted imaging, T2WI weighted imaging, diffusion tensor imaging) (Diffusion Tensor Imaging, DTI T1). Voxel based morphometry image (voxel based morphometry, VBM) the difference between the groups in gray matter volume analysis method: for engineering division of region of interest image on DTI (region of interest, ROI) the corpus callosum is divided into three parts, each part of the corpus callosum and measurement of anisotropic fraction (fractional anisotropy, FA). Statistical methods: experimental group, experimental group two and experimental group three and control group respectively for the two sample T test (Two-sample t-test), to explore the effects of sialic acid on piglet brain development during the structure. The experimental results: the experimental group compared with control group the weight of piglets, there was no significant difference in brain weight and total brain volume. By image processing and statistical analysis, the results are as follows: VBM experimental group than the control group increased gray matter volume in left dorsolateral areas of the motor cortex, the left cerebellar lobule and left primary visual skin Layer, reduced gray matter volume in areas of the left superior colliculus; two in the experimental group than the control group increased gray matter volume in areas of the left somatosensory cortex, left temporal lobe, left insula cortex, left parahippocampal gyrus, right cerebellar lobule, reducing the volume of area for the former United periaqueductal gray, Central gray, right claustrum laterodorsal thalamic nucleus, right. Three in the experimental group than the control group increased gray matter volume in areas of the left thalamus, left parahippocampal gyrus, decreased gray matter volume results area for cerebellar lobule.DTI, each experimental group compared with control group differences in corpus callosum in three regions of FA values were not statistically significant.
This study draws the following conclusions: (1) the weight of sialic acid in piglets, affect the brain weight and brain volume was not significant, the difference was not statistically significant; (2) sialic acid has a promoting effect on piglet brain development, and different forms of the existence of sialic acid effects on brain development. The piglets of different formula in experimental group one can promote the left somatosensory cortex, left temporal lobe, left insula cortex, left parahippocampal gyrus, right cerebellar lobules of cortical gray matter development; the experimental group two formula can promote the left somatosensory cortex, left temporal lobe, left insula cortex, left parahippocampal gyrus, right lateral cerebellar cortical lobule the development of; experimental group three formula can promote the development of some thalamic nuclei and parahippocampal gyrus. (3) the development of sialic acid in the corpus callosum had no significant effect, the difference was not statistically significant.

【学位授予单位】：厦门大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R174.2;R445.2

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