Evaluation of the Anxiolytic and Antidepressant Activities of the Aqueous Extract from Camellia euphlebia Merr. ex Sealy in Mice

Abstract

Camellia euphlebia Merr. ex Sealy is a traditional Chinese medicine that has been widely used for improvement of human emotions in the Guangxi Province of southern China. However, there are no studies about the anxiolytic and antidepressant activities of Camellia euphlebia. This study evaluated the anxiolytic and antidepressant activities of the aqueous extract from Camellia euphlebia (CEE) in mice. We found that administration of 400 mg/kg CEE or 20 mg/kg fluoxetine for 7 days significantly reduced the immobility time in both TST and FST. Oral administration of 100 mg/kg extract or 4 mg/kg diazepam for 7 days significantly increased the percentage of time spent and the number of entries into the open arms of the EPMT. In addition, the time spent by mice in the illuminated side of the LDBT was increased. Furthermore, pretreatment with 400 mg/kg CEE for 7 days significantly elevated the level of 5-HT and DA in the whole brain of mice. These results provide support for the potential anxiolytic and antidepressant activity of Camellia euphlebia and contribute towards validation of the traditional use of Camellia euphlebia in the treatment of emotional disorders.

Figure 1

Effects of oral administration of CEE (100, 200, or 400 mg/kg) or diazepam (4 mg/kg) on the time spent in the illuminated side of the light-dark box test in mice. The total time spent in the light box was recorded 1 h after the last administration. Values are presented as mean ± S.E.M. (n = 6 per group). ^∗ P < 0.05, ^∗∗ P < 0.01 as compared with vehicle control.

Figure 2

Effects of oral administration of CEE (100, 200, or 400 mg/kg) or diazepam (4 mg/kg) on the behaviors in the elevated plus-maze test in mice. The total time spent in the light box was recorded 1 h after the last administration. (a) The number of open arm entries during the total 5 min test in mice. (b) The time spent in open arms during the total 5 min test in mice. Values are presented as mean ± S.E.M. (n = 6 per group). ^∗ P < 0.05, ^∗∗ P < 0.01 as compared with vehicle control.

Figure 3

Effects of oral administration of CEE (100, 200, or 400 mg/kg) or fluoxetine (20 mg/kg) on the duration of immobility in the forced swimming test in mice. The total duration of immobility was recorded 1 h after the last administration. Values are presented as mean ± S.E.M. (n = 6 per group). ^∗ P < 0.05, ^∗∗ P < 0.01 as compared with vehicle control.

Figure 4

Effects of oral administration of CEE (100, 200, or 400 mg/kg) or fluoxetine (20 mg/kg) on the duration of immobility in the tail suspension test in mice. The total duration of immobility was recorded 1 h after the last administration. Values are presented as mean ± S.E.M. (n = 6 per group). ^∗ P < 0.05, ^∗∗ P < 0.01 as compared with vehicle control.

Figure 5

Effects of oral administration of CEE (100, 200, or 400 mg/kg) on the spontaneous locomotor activity in the open-field test in mice. Values are presented as mean ± S.E.M. (n = 6 per group).

Figure 6

Effects of CEE (100, 200, or 400 mg/kg) or fluoxetine (20 mg/kg) on the contents of 5-HT and DA in the whole brain of mice following the tail suspension test. Values are presented as mean ± S.E.M. (n = 6 per group). ^∗ P < 0.05, ^∗∗ P < 0.01 as compared with vehicle control.