Volatile Oil from Magnolia sieboldii Alleviates Depres-sion and Regulates Neurotransmitter Expression in...

This study explores the antidepressant efficacy of Magnolia sieboldii essential oils (MSEOs) and their underlying mechanisms in a reserpine-induced depression model utilizing mice. The impact of varying MSEOs concentrations on depressive behaviors was evaluated through the forced swimming test. Neuronal cell counts in the cerebral cortex, hippocampus, and hypothalamus were determined using Nissl staining. The expression levels of critical proteins, including 5HT-1A, 5HT-2A, and GR, were examined via immunohistochemistry. Furthermore, RT-qPCR was employed to detect the mRNA expression levels of CRF and TrkB. The findings indicate that MSEOs, particularly at medium and high doses, significantly enhance the survival motivation of mice, increase the quantity of normal neurons in the cortex and hippocampus, and mitigate depressive symptoms. Additionally, MSEOs markedly upregulate the expression of 5HT-1A and notably increase TrkB and GR levels at medium and high doses. Compared to the control group, MSEOs-treated groups demonstrate enhanced effects on neurotransmitter modulation and neuroprotection, especially at higher doses. In conclusion, MSEOs demonstrate therapeutic potential by enhancing survival motivation in mice, promoting neuronal proliferation in the brains of depressed mice, and upregulating the expression of 5HT-1A,5HT-2A, GR, CRF, and TrkB proteins. These findings suggest MSEOs may serve as a promising candidate drug for depression treatment.