Abstract: The antidepressant effects of tea polyphenols on the chronic stress-induced depression in mice and the possible underlying mechanism were investigated in this paper. The antidepressant model of chronic unpredictable mild stress mice (CUMS) was established. The activities of the mice exposed to various stress were tested in the open-field, the immobility duration of the forced swimming test and tail suspension test were measured. Meanwhile, the contents of the 5-HT and the NE in the brain tissue were determined, and the activities of superoxide dismutase (SOD), GSH-Px and the content of malondialdehyde (MDA) in the brain tissue were estimated by spectrophotometry. The CUMS-induced depressive mice exhibited significant decrease in the activities in the open-field test as compared with the control group (^#P<0.05, ^△P<0.001), while the immobility duration in the forced swimming test and tail suspension test were significantly increased, and the latency period (^#P<0.05, ^△P<0.001. ^#P<0.05, ^△P<0.05) were shortened. However, tea polyphenols ameliorated the defecits of the behavior of the mice. Moreover, tea polyphenols increased the activities of SOD, GSH-Px, and the content of 5-HT, NE, and decreased the contents of MDA in the brain tissue. The depressive status can be attenuated by the administration of tea polyphenols, the underlying mechanism might be attributed to their antioxidative property and enhancement of serotonergic functions.

Key words: depression, tea polyphenols, CUMS, SOD, 5-hydroxytryptophan