a Department of Biophysics and Clinical MRI Methods, Faculty of Medicine and Pharmacy , University of Fez , Morocco.
b Clinical Neuroscience Laboratory, Faculty of Medicine and Pharmacy , University of Fez , Morocco.
Nutr Neurosci. 2017 Nov;20(9):505-512. doi: 10.1080/1028415X.2016.1191165. Epub 2016 Jun 8.
The goal of this study was assessing the intermittent fasting effect on brain plasticity and oxidative stress (OS) using blood-oxygenation-level dependent (BOLD)-functional magnetic resonance image (fMRI) approach. Evidences of physiological and molecular phenomena involved in this process are discussed and compared to reported literature.
Six fully healthy male non-smokers volunteered in this study. All volunteers were right handed, and have an equilibrated, consistent and healthy daily nutritional habit, and a healthy lifestyle. Participants were allowed consuming food during evening and night time while fasting with self-prohibiting food and liquids during 14 hours/day from sunrise to sunset. All participants underwent identical brain BOLD-fMRI protocol. The images were acquired in the Department of Radiology and Clinical Imaging of the University Hospital of Fez, Fez, Morocco. The anatomical brain and BOLD-fMRIs were acquired using a 1.5-Tesla scanner (Signa, General Electric, Milwaukee, United States). BOLD-fMRI image acquisition was done using single-shot gradient echo echo-planer imaging sequence. BOLD-fMRI paradigm consisted of the motor task where volunteers were asked to perform finger taping of the right hand. Two BOLD-fMRI scan sessions were performed, the first one between the 5th and 10th days preceding the start of fasting and the second between days 25th and 28th of the fasting month. All sessions were performed between 3:30 PM and 5:30 PM. Although individual maps were originated from different individual participants, they cover the same anatomic area in each case. Image processing and statistical analysis were conducted with Statistical Parameter Mapping version 8 (2008, Welcome Department of Cognitive Neurology, London UK).
The maximal BOLD signal changes were calculated for each subject in the motor area M1; Activation maps were calculated and overlaid on the anatomical images. Group analysis of the data was performed, and the average volume and the maximum intensity of BOLD signal in the activated area M1 was determined for all studied volunteers. The current study allowed measuring regional brain volumes and neural network activity before and during an extended period of fasting using BOLD-fMRI. This demonstrated and confirmed the impact of fasting on human brain structure and function. Further studies are required to elucidate mechanisms and enable direct inference of a diet-induced OS effect on the brain.
本研究旨在通过血氧水平依赖（BOLD）功能磁共振成像（fMRI）方法评估间歇性禁食对大脑可塑性和氧化应激（OS）的影响。讨论了涉及这一过程的生理和分子现象的证据，并与已报道的文献进行了比较。
本研究招募了 6 名完全健康的男性非吸烟者。所有志愿者均为右利手，具有均衡、一致和健康的日常营养习惯以及健康的生活方式。参与者被允许在晚上和夜间进食，而在每天 14 小时内禁食，即从日出到日落期间禁止进食和饮水。所有参与者均接受了相同的大脑 BOLD-fMRI 方案。图像在摩洛哥非斯大学附属医院放射科和临床影像学部采集。使用 1.5T 扫描仪（美国密尔沃基通用电气公司 Signa）采集大脑解剖和 BOLD-fMRI。BOLD-fMRI 图像采集采用单次激发梯度回波回波平面成像序列。BOLD-fMRI 范式包括运动任务，要求志愿者用右手进行手指敲击。进行了 2 次 BOLD-fMRI 扫描，第 1 次在禁食开始前的第 5 天至第 10 天之间进行，第 2 次在禁食月的第 25 天至第 28 天之间进行。所有扫描均在下午 3:30 至 5:30 之间进行。虽然个体图谱源自不同的个体参与者，但它们在每种情况下都覆盖相同的解剖区域。使用统计参数映射版本 8（2008 年，英国伦敦欢迎认知神经病学系）进行图像处理和统计分析。
在运动区 M1 中为每位受试者计算了最大 BOLD 信号变化；计算了激活图，并叠加在解剖图像上。对数据进行了组分析，确定了所有研究志愿者 M1 激活区的平均体积和 BOLD 信号的最大强度。本研究允许使用 BOLD-fMRI 在延长的禁食期间测量大脑的区域体积和神经网络活动。这证明并证实了禁食对人脑结构和功能的影响。需要进一步的研究来阐明机制，并能够直接推断饮食诱导的 OS 对大脑的影响。
