Environmental Enrichment Increased Bdnf Transcripts in the Prefrontal Cortex: Implications for an Epigenetically...

Area of Science:

• Neuroscience
• Epigenetics
• Behavioral Science

Background:

• Environmental enrichment (EE) modulates brain physiology and behavior, potentially via brain-derived neurotrophic factor (BDNF).
• The specific Bdnf exon expression and epigenetic regulation under EE remain poorly understood.

Purpose of the Study:

• To investigate the transcriptional and epigenetic effects of 54-day EE exposure on BDNF in the mouse prefrontal cortex (PFC).
• To analyze individual BDNF exon mRNA expression and DNA methylation of a key regulator, exon IV.

Main Methods:

• Analysis of Bdnf exons II, IV, VI, and IX mRNA expression in the PFC of C57BL/6 male mice (n=33) after 54-day EE exposure.
• Assessment of DNA methylation profiles at two CpG sites within Bdnf exon IV.
• Evaluation of anxiety-like behavior and plasma corticosterone levels.

Main Results:

• EE upregulated Bdnf exons II, IV, VI, and IX mRNA expression in the PFC.
• EE reduced DNA methylation levels at two CpG sites in Bdnf exon IV.
• No significant changes in anxiety-like behavior or corticosterone levels were observed.

Conclusions:

• EE exposure induces epigenetic modifications in the PFC, specifically reducing DNA methylation of Bdnf exon IV.
• Findings suggest an EE-induced epigenetic control of BDNF exon expression, potentially involving exon IV methylation.
• This study elucidates the Bdnf gene's transcriptional and epigenetic regulation within the PFC under environmental enrichment.