Honokiol reverses depressive-like behavior and decrease in brain BDNF levels induced by chronic corticosterone injections in mice

Abstract

BackgroundHonokiol, an active component isolated and purified from Chinese traditional herb Magnolia officinalis. It is known to have a wide range of biological activities including antidepressant-like effects which have been observed in stress-induced depression models. This study was designed to investigate the antidepressant potential of honokiol in corticosteroid induced model of depression. MethodAdult Swiss albino mice were injected with 40 mg/kg of corticosterone (CORT) chronically for 21 days. Behavioral and biochemical parameters were estimated. Moreover, since brain derived neurotrophic factor (BDNF) has been implicated in antidepressant effects of many drugs, we also evaluated the effects of honokiol on BDNF in the hippocampus. ResultsThe results showed that the 3-week CORT injections caused the significant elevation in serum CORT levels in mice. Repeated CORT injections also caused depression-like behavior in mice, as indicated by the significant decrease in sucrose consumption (P < 0.01) and increase in immobility time in the forced swim test (P < 0.001). Moreover, it was found that BDNF levels in the hippocampus were significantly decreased (P < 0.001) in CORT-treated mice. Treatment of the mice with honokiol significantly suppressed the depression-like behavior and increased brain BDNF levels (P < 0.01) in CORT-treated mice. ConclusionThese results conclude that honokiol produces an antidepressant-like effect in CORT-induced depression, which is possibly mediated by increasing BDNF expression in the hippocampus.