Antidepressant-Like Effect of Aromatherapy with Magnolia sieboldii Essential Oils on Depression Mice

Abstract

Globally, depression is the fourth most common disorder. It is difficult to treat and prone to recurrent episodes. To elucidate the antidepressant effect and mechanism of action of Magnolia sieboldii aromatherapy, the main components of M. sieboldii essential oils were analyzed using GC-MS. A mouse model of depression, established by repeated intraperitoneal injection of reserpine, was used to probe antidepressant efficacy. Behavioral tests were used to evaluate depressive behavior in mice. In in vivo animal studies, changes in the number of measured neurons were detected using Nissl staining, and GR protein expression was examined using immunohistochemistry. The relative expression levels of 5-hydroxytryptamine (5-HT1A) and brain-derived neurotrophic factor (BDNF) were detected using western blot (WB). The results showed that the essential oils of M. sieboldii are mainly composed of β-elemene (22.11%), trans-β-ocimene (14.87%), germacrene D (7.27%), and nerolidol (4.51%). The expression of GR protein was substantially upregulated in the tissues of mice treated with the essential oils of M. sieboldii. WB showed that the components of M. sieboldii essential oils modulated the expression of BDNF and 5-HT in serum, which remarkably attenuated depressive behavior in mice. In addition, a medium concentration of M. sieboldii substantially ameliorated depressive-like behavior in mice and increased the serum levels of 5-HT1A and BDNF. This study suggests that a medium concentration of M. sieboldii has a prominent antidepressant effect.