Sampedro-Piquero P, De Bartolo Paola, Petrosini Laura, Zancada-Menendez C, Arias J L, Begega A
Laboratorio de Neurociencias, Departamento de Psicología, Universidad de Oviedo, Instituto de Neurociencias del Principado de Asturias, INEUROPA, Plaza Feijoo s/n, 33003 Oviedo, Spain.
Department of Psychology, University "Sapienza", via dei Marsi 78, 00185 Rome, Italy; IRCCS S. Lucia Foundation, via del Fosso di Fiorano 64, 00143 Rome, Italy.
Neurobiol Learn Mem. 2014 Oct;114:16-25. doi: 10.1016/j.nlm.2014.04.002. Epub 2014 Apr 12.
Currently, little is known about the effect of environmental enrichment (EE) on astrocytic plasticity, especially during aging. Given the newly discovered role of the astrocytes in regulating the synaptic transmission and thereby, the cognitive functions, we aimed to study the impact of EE on the performance in a spatial memory task and on the number and morphology of GFAP immunopositive cells in the dorsal hippocampus. After two months of EE (3 h/per day), the animals were tested in the Radial-Arm Water Maze (RAWM) for four days, with six daily trials. Next, we analyzed the changes in the GFAP immunopositive cells in CA1, CA3 and Dentate Gyrus (DG). Behavioral results showed that, even in advanced ages, EE improved the performance in a spatial memory task. Also, we found that aged rats submitted to EE had more GFAP immunopositive cells in the DG and more complex astrocytes, revealed by Sholl analysis, in all hippocampal subfields with respect to the other experimental conditions. Interestingly, the learning of a spatial memory task produced more morphological complexity and higher levels of GFAP immunopositive cells with regard to a standard control group, but not at the same level of the enriched groups. Thus, it is possible that the plastic changes found in the hippocampal astrocytes after EE are involved in a brain reserve to cope with age-related cognitive impairments.
目前，关于环境富集（EE）对星形胶质细胞可塑性的影响知之甚少，尤其是在衰老过程中。鉴于星形胶质细胞在调节突触传递进而调节认知功能方面新发现的作用，我们旨在研究EE对空间记忆任务表现以及背侧海马中胶质纤维酸性蛋白（GFAP）免疫阳性细胞数量和形态的影响。在进行两个月的EE（每天3小时）后，对动物进行为期四天的放射状臂式水迷宫（RAWM）测试，每天进行六次试验。接下来，我们分析了海马CA1、CA3和齿状回（DG）中GFAP免疫阳性细胞的变化。行为学结果表明，即使在高龄阶段，EE也能改善空间记忆任务的表现。此外，我们发现，与其他实验条件相比，接受EE的老年大鼠在DG中有更多的GFAP免疫阳性细胞，并且通过Sholl分析显示，在所有海马亚区中，星形胶质细胞更复杂。有趣的是，与标准对照组相比，空间记忆任务的学习使星形胶质细胞形态更复杂，GFAP免疫阳性细胞水平更高，但不如富集组。因此，EE后海马星形胶质细胞中发现的可塑性变化可能参与了一种大脑储备，以应对与年龄相关的认知障碍。
