Soares Roberto O, Horiquini-Barbosa Everton, Almeida Sebastião S, Lachat João-José
Laboratory of Neuroanatomy, Department of Surgery and Anatomy, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil.
Laboratory of Nutrition & Behavior, Department of Psychology, Faculty of Philosophy Sciences and Letters of Ribeirão Preto, University of São Paulo, São Paulo, Brazil.
Behav Brain Res. 2017 Sep 29;335:55-62. doi: 10.1016/j.bbr.2017.08.012. Epub 2017 Aug 8.
As early protein malnutrition has a critically long-lasting impact on the hippocampal formation and its role in learning and memory, and environmental enrichment has demonstrated great success in ameliorating functional deficits, here we ask whether exposure to an enriched environment could be employed to prevent spatial memory impairment and neuroanatomical changes in the hippocampus of adult rats maintained on a protein deficient diet during brain development (P0-P35). To elucidate the protective effects of environmental enrichment, we used the Morris water task and neuroanatomical analysis to determine whether changes in spatial memory and number and size of CA1 neurons differed significantly among groups. Protein malnutrition and environmental enrichment during brain development had significant effects on the spatial memory and hippocampal anatomy of adult rats. Malnourished but non-enriched rats (MN) required more time to find the hidden platform than well-nourished but non-enriched rats (WN). Malnourished but enriched rats (ME) performed better than the MN and similarly to the WN rats. There was no difference between well-nourished but non-enriched and enriched rats (WE). Anatomically, fewer CA1 neurons were found in the hippocampus of MN rats than in those of WN rats. However, it was also observed that ME and WN rats retained a similar number of neurons. These results suggest that environmental enrichment during brain development alters cognitive task performance and hippocampal neuroanatomy in a manner that is neuroprotective against malnutrition-induced brain injury. These results could have significant implications for malnourished infants expected to be at risk of disturbed brain development.
由于早期蛋白质营养不良对海马结构及其在学习和记忆中的作用具有极其持久的影响，并且环境富集已在改善功能缺陷方面取得了巨大成功，因此我们在此探讨，对于在脑发育期间（P0 - P35）维持蛋白质缺乏饮食的成年大鼠，暴露于富集环境是否可用于预防空间记忆损害和海马的神经解剖学变化。为了阐明环境富集的保护作用，我们使用莫里斯水迷宫任务和神经解剖学分析来确定空间记忆的变化以及CA1神经元的数量和大小在各组之间是否存在显著差异。脑发育期间的蛋白质营养不良和环境富集对成年大鼠的空间记忆和海马解剖结构有显著影响。营养不良但未富集的大鼠（MN）找到隐藏平台所需的时间比营养良好但未富集的大鼠（WN）更长。营养不良但经过富集的大鼠（ME）表现优于MN组，与WN组相似。营养良好但未富集的大鼠和经过富集的大鼠（WE）之间没有差异。在解剖学上，MN组大鼠海马中的CA1神经元数量比WN组少。然而，也观察到ME组和WN组大鼠保留的神经元数量相似。这些结果表明，脑发育期间的环境富集以一种对营养不良引起的脑损伤具有神经保护作用的方式改变了认知任务表现和海马神经解剖结构。这些结果可能对预期有脑发育紊乱风险的营养不良婴儿具有重要意义。
