Treadmill exercise alters histone acetylation differently in rats exposed or not exposed to aversive learning context

Abstract

Epigenetic modifications have been linked to memory formation after learning context exposure and to exercise effects on memory performance. The aim of this study was to investigate the effect of treadmill exercise (20min/day during 2weeks) on H3K14 acetylation and H3S10 phosphorylation levels in the hippocampi of 3-month-old Wistar rats exposed and not exposed to aversive learning context. Male Wistar rats aged 2–3months were assigned to non-exercised (sedentary) and exercised (running daily for 20min for 2weeks) groups. Single-trial step-down inhibitory avoidance (IA) conditioning was employed as an aversive memory model. Epigenetic parameters were determined 30min after the IA test. A decrease in the H3K14 acetylation in the hippocampus 24h after IA training (30min after test session) was observed. Exercise reversed the IA effect, and no effect was observed in the non-IA exposed group. Our data support the hypothesis that modulation of H3K14 acetylation levels in the hippocampus might be related, at least in part, to exercise effects on aversive memory.