Radiation Biology Department, National Center for Radiation Research and Technology (NCRRT), Atomic Energy Authority, P.O. Box, 29 Nasr City, Cairo, Egypt.
Brain Res Bull. 2022 Aug;186:136-142. doi: 10.1016/j.brainresbull.2022.05.011. Epub 2022 May 28.
This study aims to investigate the impact of gamma-radiation on the cerebral- and cerebellar-cortex of rat's brain. Animals were whole-body exposed to 3 Gy, every 3 days, up to 9 Gy, and sacrificed 1 h, 1, 3, 7 & 10 days post the last radiation-dose. Irradiation triggers oxidative stress. Superoxide dismutase, catalase, glutathione reductase decreased, malondialdehyde and protein carbonyl increased from the 1st hour till the 10th day in both tissues. Glutathione peroxidase and glutathione decreased from the 1st hour in the cerebral-cortex, and 3rd day in the cerebellar-cortex. Irradiation increased the inflammatory marker, tumor necrosis factor-alpha, and the apoptotic markers, cytochrome-c and caspase-3 from the 1st hour till the 10th day in both tissues. β-amyloid was observed the 7th and 10th day in cerebral-cortex and 3rd, 7th and 10th day in cerebellar-cortex. Irradiation change the level of neurotransmitters. Norepinephrine decreased from the 1st hour in both tissues, while dopamine, epinephrine, aspartic acid, glutamic acid decreased, and gamma amino butyric acid increased from the 1st hour in the cerebral-cortex and later on the 3rd day in the cerebellar-cortex. Electroencephalographic measurement (EEG) showed significant decreases in the frequencies of beta-(>12 Hz) alpha-(7-12 Hz), theta-(4-7 Hz), and delta-rhythms (1-4 Hz) from the 1st hour in both occipital and parietal areas of the brain. Gamma-irradiation triggers oxidative stress, change the level of neurotransmitters, increase inflammatory and apoptotic responses, enhance deposition of amyloid plaque in the cerebral- and cerebellar- cortex, and decrease brain electrical activity in occipital and parietal areas of the brain.
本研究旨在探讨γ辐射对大鼠大脑皮质和小脑的影响。动物接受全身 3Gy 照射，每 3 天一次，最高达 9Gy，并在最后一次照射后 1 小时、1 天、3 天、7 天和 10 天处死。照射引发氧化应激。超氧化物歧化酶、过氧化氢酶、谷胱甘肽还原酶活性降低，丙二醛和蛋白质羰基含量在 1 小时至 10 天内均升高。谷胱甘肽过氧化物酶和谷胱甘肽在大脑皮质中从 1 小时开始下降，在小脑皮质中从第 3 天开始下降。照射使炎症标志物肿瘤坏死因子-α和凋亡标志物细胞色素 c 和半胱天冬酶-3从 1 小时到 10 天在两种组织中均增加。β-淀粉样蛋白在大脑皮质中第 7 天和第 10 天，在小脑皮质中第 3 天、第 7 天和第 10 天被观察到。照射改变了神经递质的水平。去甲肾上腺素在两种组织中从 1 小时开始下降，而多巴胺、肾上腺素、天冬氨酸、谷氨酸在大脑皮质中从 1 小时开始下降，在小脑皮质中从第 3 天开始下降，γ-氨基丁酸开始升高。脑电图（EEG）测量显示，在大脑的枕叶和顶叶区域，β-（>12Hz）、α-（7-12Hz）、θ-（4-7Hz）和 δ-（1-4Hz）频率从 1 小时开始显著降低。γ 辐射引发氧化应激，改变神经递质水平，增加炎症和凋亡反应，增强大脑皮质和小脑皮质中淀粉样斑块的沉积，降低大脑枕叶和顶叶区域的脑电活动。
