The animal models and related mechanisms for anti-depression research works

Prof. Lee-Yan Sheen

Institute of Food Science and Technology, National Taiwan University

 

WHO predicted that major depressive disorder (MDD) will be the number one disability and mortality disease in the world by the year of 2030. Due to the limitation of efficacy and undesirable adverse effects of antidepressant, the chronic and recurrent depression is still present at high rates. Therefore, using animal models are important tools for investigating and looking for the antidepressant-like food ingredients or herbal medicines. Our research mainly focuses on the roles of traditional Chinese dietary therapies on MDD prevention and complementary treatments. Forced swim test (FST), tail suspension test (TST), unpredictable chronic mild stress (UCMS) and chronic social defeat stress (CSDS) are very effective and well-established platforms to predict the antidepressant-like efficacy in rodent. Gastrodia elata Blume (GE) is commonly cultivated in China and Korea. GE is typically used as both food ingredient and Chinese medicine for thousands of years. Recently, we demonstrated that water extract of GE (WGE) had the antidepressant-like effect in FST, possibly via significantly reduced the cerebral turnover rates of serotonin and dopamine. Moreover, WGE significantly reversed the sucrose preference in UCMS. Maybe due to WGE normalized the HPA axis because of regulating the concentration of serum corticosterone as well as inhibiting the activity and protein expression of MAO-A, and increasing tyrosine hydroxylase (TH) level. In CSDS model, our data showed that WGE exerted antidepressant-like effects and possible mechanisms might be via the activation of BDNF/CREB/Akt signaling pathway in the hippocampus. In addition, our study also showed that lemon essential oil reduced immobility time in the TST through the modulation in the levels of norepinephrine, dopamine, and serotonin in the prefrontal cortex, striatum, and hippocampus. Thus, food and herbal medicine might be the alternative way for the prevention of depression or used as a complementary therapy for the clinical medicine to treat depression nowadays.