The known effects of aging on the brain and behavior include impaired cognition, increases in anxiety and depressive-like behaviors, and reduced locomotor activity. Environmental exposures and interventions also influence brain functions during aging. We investigated the effects of normal aging under controlled environmental conditions and in the absence of external interventions on locomotor activity, cognition, anxiety and depressive-like behaviors, immune function and hippocampal gene expression in C57BL/6 mice. Healthy mice at 4, 9, and 14 months of age underwent behavioral testing using an established behavioral battery, followed by cellular and molecular analysis using flow cytometry, immunohistochemistry, and quantitative PCR. We found that 14-month-old mice showed significantly reduced baseline locomotion, increased anxiety, and impaired spatial memory compared to younger counterparts. However, no significant differences were observed for depressive-like behavior in the forced-swim test. Microglia numbers in the dentate gyrus, as well as CD8+ memory T cells increased towards late middle age. Aging processes exerted a significant effect on the expression of 43 genes of interest in the hippocampus. We conclude that aging is associated with specific changes in locomotor activity, cognition, anxiety-like behaviors, neuroimmune responses and hippocampal gene expression.

中文翻译：

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衰老对运动，认知和情感行为，神经免疫反应和海马基因表达的影响。

衰老对大脑和行为的已知影响包括认知障碍，焦虑和抑郁样行为增加以及运动能力降低。环境暴露和干预也会影响衰老过程中的大脑功能。我们调查了正常衰老在可控的环境条件下和在没有外部干预的情况下对C57BL / 6小鼠运动活动，认知，焦虑和抑郁样行为，免疫功能和海马基因表达的影响。在4、9和14个月大时对健康小鼠进行行为测试，使用既定的行为电池，然后使用流式细胞仪，免疫组织化学和定量PCR进行细胞和分子分析。我们发现14个月大的小鼠表现出明显的基线运动减少，焦虑增加，与年轻一代相比，空间记忆受损。但是，在强迫游泳测试中，没有观察到抑郁症样行为的显着差异。齿状回中的小胶质细胞数量以及CD8 +记忆T细胞在中年后期增加。衰老过程对海马中43个目的基因的表达产生了重要影响。我们得出结论，衰老与运动活动，认知，焦虑样行为，神经免疫反应和海马基因表达的特定变化有关。衰老过程对海马中43个目的基因的表达产生了重要影响。我们得出结论，衰老与运动活动，认知，焦虑样行为，神经免疫反应和海马基因表达的特定变化有关。衰老过程对海马中43个目的基因的表达产生了重要影响。我们得出结论，衰老与运动活动，认知，焦虑样行为，神经免疫反应和海马基因表达的特定变化有关。