Velosky Alexander G, Tucker Laura B, Fu Amanda H, Liu Jiong, McCabe Joseph T
Department of Anatomy, Physiology & Genetics, F.E. Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD, United States.
Department of Anatomy, Physiology & Genetics, F.E. Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD, United States; Pre-Clinical Studies Core, Center for Neuroscience and Regenerative Medicine, Bethesda, MD, United States.
Behav Brain Res. 2017 May 1;324:115-124. doi: 10.1016/j.bbr.2017.02.017. Epub 2017 Feb 15.
In contact sports, repetitive concussive brain injury (rCBI) is the prevalent form of head injury seen in athletes. The need for effective treatment is urgent as rCBI has been associated with a host of cognitive, behavioral and neurological complaints. There has been a growing trend in the use of female animals in pre-clinical research, but few studies have investigated possible sex differences following rCBI. The goal of the current study was to determine any differences between male and female C57BL/6J mice on assessments of learning and memory after repetitive concussive injury. Following rCBI by impact to the scalp, male mice exhibited longer righting reflexes during acute recovery. In both sexes, there were no evident histopathological changes observed in the underlying cerebral cortex or hippocampus. Reactive astrogliosis was elevated in the corpus callosum and optic tract, and astrogliosis was slightly less in the optic tract of female mice. rCBI mice exhibited impairment during the learning phase of the Morris water maze (MWM), but female mice, in comparison to male mice, were observed to have superior spatial memory during standard MWM probe trials. Female mice were overall more active, evidenced by greater distances traveled in the y-maze and greater swim speeds in the MWM. The results of this study demonstrate sex differences in cognitive performance following rCBI and support previous research suggesting the neuroprotective role of sex in brain injury.
在接触性运动中，重复性脑震荡损伤（rCBI）是运动员中常见的头部损伤形式。由于rCBI与一系列认知、行为和神经方面的不适有关，因此迫切需要有效的治疗方法。临床前研究中使用雌性动物的趋势日益增加，但很少有研究调查rCBI后可能存在的性别差异。本研究的目的是确定重复性脑震荡损伤后，雄性和雌性C57BL/6J小鼠在学习和记忆评估上的差异。通过撞击头皮造成rCBI后，雄性小鼠在急性恢复期间表现出更长的翻正反射时间。在两性中，未观察到大脑皮层或海马体有明显的组织病理学变化。胼胝体和视束中的反应性星形胶质细胞增生增加，雌性小鼠视束中的星形胶质细胞增生略少。rCBI小鼠在莫里斯水迷宫（MWM）的学习阶段表现出损伤，但与雄性小鼠相比，在标准MWM探针试验中观察到雌性小鼠具有更好的空间记忆。雌性小鼠总体上更活跃，这在Y迷宫中行进的距离更远以及在MWM中的游泳速度更快得到证明。本研究结果表明rCBI后认知表现存在性别差异，并支持先前关于性别在脑损伤中具有神经保护作用的研究。
