Running during adolescence rescues a maternal separation‐induced memory impairment in female mice: Potential role of differential exon‐specific BDNF expression

Luis Eduardo Wearick‐Silva, Paul R. Marshall, Thiago Wendt Viola, Anderson Centeno‐Silva, Lucas Araújo de Azeredo, Rodrigo Orso, Xiang Li, Márcio Vinı́cius Fagundes Donadio, Timothy W. Bredy, Rodrigo Grassi‐Oliveira

Developmental Psychobiology · 2016 · 29 citations · 39 references

TL;DR

Early life stress, such as maternal separation, is linked to memory deficits through altered BDNF signaling, yet the capacity of exercise to counteract these effects remains poorly understood. In this study, adolescent mice that experienced maternal separation were subjected to a 3‑week voluntary running regimen, after which recognition memory was assessed and hippocampal expression of BDNF exons I, IV, and IX was quantified. Maternal separation impaired recognition memory, but exercise restored performance and modulated BDNF transcripts—raising exon I, lowering exon IV, and selectively increasing exon IX in separated animals—indicating that exercise can mitigate memory deficits via dynamic BDNF regulation.

Abstract

Abstract Exposure to early life stress has been associated with memory impairments related to changes in brain‐derived neurotrophic factor (BDNF) signaling. However, the potential impact of physical exercise to reverse these effects of maternal separation has been under investigated. Mice were subjected to maternal separation during the first 2 weeks of life and then exposed to a 3‐week running protocol during adolescence. The spontaneous object recognition task was performed during adolescence followed by analysis of hippocampal expression of exons I, IV, and IX of the BDNF gene. As expected, maternal separation impaired recognition memory and this effect was reversed by exercise. In addition, running increased BDNF exon I expression, but decreased expression of BDNF exon IV in all groups, while exon IX expression increased only in MS animals exposed to exercise. Our data suggest that memory deficits can be attenuated by exercise and specific transcripts of the BDNF gene are dynamically regulated following both MS and exercise.

References

39