Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy.
Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy.
Exp Gerontol. 2021 Apr;146:111225. doi: 10.1016/j.exger.2020.111225. Epub 2020 Dec 31.
It has clearly been demonstrated that cognitive stimulation, physical exercise, and social engagement help counteract age-related cognitive decline. However, several important issues remain to be addressed. Given the wide differences in cognitive impairment found among individuals of the same age, identifying the subjects who will benefit most from late-life interventions is one such issue. Environmental Enrichment (EE) is a particularly valuable approach to do this. In this study, aged (21-month-old) rats were assigned to a better (BL) or a worse (WL) learner group (training phase) and to a non-impaired (NI) or an impaired (I) group (probe phase) by their performance on the Morris Water Maze, using the test performances of adult (12-month-old) rats as the cut-offs. The aged rats were retested after a 12-week EE or standard housing (SH) protocol. After 12 weeks, the performances of SH rats had deteriorated, whereas all rats benefited from EE, albeit in different ways. In particular, the animals assigned to the BL and the NI groups prior to EE still performed as well as the adult rats (performance preservation) whereas, critically, the animals assigned to the WL and the I groups before EE showed such improved performances that they reached the level of the adult rats (performance improvement), despite having aged further. EE seems to induce the preservation in BLs and the improvement in WLs of spatial search strategies and the preservation in NIs and the increase in Is of a focused and protract research of the escape point. Our findings suggest that late-life EE prevents spatial learning and memory decline in still cognitively preserved animals and stimulates residual functional reserve in already cognitively compromised animals. Future research should focus on individually tailored stimulation protocols to improve their effect and afford a better understanding of the underlying processes.
很明显，认知刺激、体育锻炼和社会参与有助于抵抗与年龄相关的认知能力下降。然而，仍有几个重要问题需要解决。鉴于相同年龄的个体之间存在广泛的认知障碍差异，确定最受益于晚年干预的受试者是其中一个问题。环境丰富（EE）是一种特别有价值的方法。在这项研究中，年龄较大的（21 个月大）大鼠根据其在 Morris 水迷宫上的表现被分配到更好的（BL）或更差的（WL）学习者组（训练阶段）和非受损（NI）或受损（I）组（探针阶段），使用成年（12 个月大）大鼠的测试表现作为截止值。在 12 周的 EE 或标准饲养（SH）方案后，对老年大鼠进行重新测试。经过 12 周后，SH 大鼠的表现恶化，而所有大鼠都从 EE 中受益，尽管方式不同。特别是，在 EE 之前被分配到 BL 和 NI 组的动物仍然表现得像成年大鼠一样好（表现保留），而关键的是，在 EE 之前被分配到 WL 和 I 组的动物表现出如此改善的表现，以至于它们达到了成年大鼠的水平（表现改善），尽管它们进一步老化。EE 似乎诱导 BL 的保留和 WL 的空间搜索策略的改善，以及 NI 的保留和 Is 的增加，即集中和持久地搜索逃逸点。我们的研究结果表明，晚年 EE 可预防认知保留的动物的空间学习和记忆下降，并刺激已经认知受损的动物的剩余功能储备。未来的研究应侧重于个体化的刺激方案，以提高其效果，并更好地理解潜在的过程。
