Hyperforin alleviates mood deficits of adult rats suffered from early separation

• Early separation from rat parents can lead to the mood deficits and depression.
• Hyperforin, active constituent of Hypericum perforatum, potently alleviates anxiety behavior.
• Hyperforin abolishes depressive symptoms evoked by early separation.

In this study, we aimed to explore the effect of hyperforin (Hyp) on adult rats suffered from early separation. Wistar infant rats were randomly divided into three groups: control group (CON), early separation from parents group (ESP), and early separation from parents + treatment with 3 mg/kg/day Hyp group (ESP + Hyp). Postnatal rats of ESP group and ESP + Hyp group were separated from their mothers for 6 h every day on the 14th day after birth, and this separation lasted for 3 weeks, while rats of CON group had no separation. Hyperforin was intragastric administrated on the 21th day after birth, and lasted for 2 weeks in ESP + Hyp group. After separation, adult rats were evaluated by using the open field test (OFT), novelty suppressed feeding test (NSF) and forced swimming test (FST). In OFT, time spent in central grids was much shorter in ESP group compared with that of CON group. After treatment with hyperforin, time spent in central area was much longer compared with that of ESP group. In NSF, the feeding latency of ESP group was much longer than that of CON group. After treatment with hyperforin, the feeding latency was shorter compared with that of ESP group. In FST, score of ESP group was markedly higher than that of CON group. Interestingly, the score was obviously lower in ESP + Hyp group than that of ESP group. In conclusion, these results suggest that hyperforin is able to alleviate anxiety and remit depression in ESP rats.