Genetic and behavioural requirements for structural brain plasticity

Abstract

1AbstractHuman MRI studies show that experience can lead to changes in the volume of task-specific brain regions; however, the behavioural and molecular processes driving these changes remain poorly understood. Here, we used in-vivo mouse MRI and RNA sequencing to investigate the neuroanatomical and transcriptional changes induced by environmental enrichment, exercise, and social interaction. Additionally, we asked whether the volume changes require CREB, a transcription factor critical for memory formation and neuronal plasticity. Enrichment rapidly increased cortical and hippocampal volume, and these effects were not attributable to exercise or social interaction. Instead, they likely arise from learning and sensorimotor experience. Nevertheless, the volume changes were not attenuated in mice with memory impairments caused by loss of CREB, indicating that these effects are driven by processes distinct from this canonical learning and memory pathway. Finally, within brain regions that underwent volume changes, enrichment increased the expression of genes associated with axonogenesis, dendritic spine development, synapse structural plasticity, and neurogenesis, suggesting these processes underlie the volume changes detected with MRI.

Epitranscriptomic Regulation in Synaptic Plasticity, Aging and Neurodegeneration

“…Although a short (2 weeks) continuous exposure to EE did not display significant improvements in contextual or spatial learning (Appendix Figure 5), other studies have reported significant structural changes in the brain of these animals, including increased volume and gene expression changes, independent from classical transcriptional programs (T.-Y. Vousden et al 2018). Therefore, it would be of great interest to compare shorter, periodic EE protocols and analyze the hippocampal epitranscriptomic state of these mice to find commonalities and differences with the results obtained thus far.…”