Neurodegeneration in thiamine deficient rats-A longitudinal MRI study
Neurodegeneration in thiamine deficient rats-A longitudinal MRI study
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DOI：
10.1016/j.brainres.2009.10.032
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发表时间：
2010-01-13
期刊：
影响因子：
2.9
通讯作者：
Fattal-Valevski, Aviva
中科院分区：
文献类型：
--
作者：
Dror, Vered;Eliash, Sarah;Fattal-Valevski, Aviva
伴随线粒体功能障碍的选择性神经变性是阿尔茨海默病和帕金森病等神经退行性疾病的特征。大鼠硫胺素缺乏症（TD）是研究导致慢性氧化缺陷导致选择性神经元损失的细胞和分子机制的模型。 TD 大鼠的神经变性会在 12 至 14 天的时间内发生，并且可以通过硫胺素给药部分逆转。本研究的目的是使用 T-2 磁共振成像和扩散张量成像 (DTI) 来表征神经变性的体内进展和 TD 中的神经元拯救过程。每只大鼠在 TD 诱导前（第 0 天）、神经系统症状出现前（第 10 天）、症状阶段（第 12 和 14 天）以及恢复期间（第 31 和 87 天）均进行扫描。时间依赖性病变主要出现在丘脑和下丘。第 10 天发现下丘的分数各向异性 (FA) 早期下降，丘脑的程度较小，而 T-2 参数最早可检测到的变化仅发生在第 12 天。硫胺素恢复后，丘脑的 FA 值仍然显着较低，表明神经元结构发生不可逆的紊乱和替换。虽然额叶皮层的 T-2 值没有显示出病变，但 FA 值在第 14 天和第 31 天显着增加。在恢复期间观察到并持续存在侧脑室扩大。这项纵向 MRI 研究表明，TD MRI 可以检测神经退行性变和神经元恢复。在 TD 病变的早期检测中，DTI 比 T-2 标测更敏感。 (C) 2009 Elsevier B.V. 保留所有权利。
Selective neurodegeneration accompanied by mitochondrial dysfunction characterizes neuro degenerative disorders such as Alzheimer's and Parkinson's diseases. Thiamine deficiency (TD) in rats is a model for the study of cellular and molecular mechanisms that lead to selective neuronal loss caused by chronic oxidative deficits. Neurodegeneration in TD-rats develops over a period of 12 to 14 days and can be partially reversed by thiamine administration. The aim of this study was to characterize the in-vivo progression of neurodegeneration and the neuronal rescue processes in TD using T-2 magnetic resonance mapping and diffusion tensor imaging (DTI). Each rat was scanned prior to TD induction (day 0), before the appearance of neurological symptoms (day 10), during the symptomatic stage (days 12 and 14) and during the recuperation period (days 31 and 87). Time-dependent lesions were revealed mainly in the thalamus and the inferior colliculi. Early decrease in the fractional anisotropy (FA) was found on day 10 in the inferior colliculi and to a lesser degree in the thalamus, while the earliest detectable changes in the T-2 parameter occurred only on day 12. FA values in the thalamus remained significantly low after thiamine restoration, suggesting irreversible disarrangement and replacement of neuronal structures. While T-2 values in the frontal cortex demonstrated no lesions, FA values significantly increased on days 14 and 31. An enlargement of the lateral ventricles was observed and persevered during the recovery period. This longitudinal MRI study demonstrated that in TD MRI can detect neurodegeneration and neuronal recovery. DTI is more sensitive than T-2 mapping in the early detection of TD lesions. (C) 2009 Elsevier B.V. All rights reserved.