Ameliorative effect of betulin from Betula platyphylla bark on scopolamine-induced amnesic mice

Figures & data

Fig. 1. Effects of betulin and betulinic acid on the scopolamine-induced amnesic mice in the passive avoidance test.

Notes: Two hours before the training trial, mice received test samples (p.o.). After 90 min, amnesia was induced in orally treated mice with by scopolamine injection (1 mg/kg body weight, s.c.). Twenty-four hours after the training trial, the mice were again placed in the light compartment. The escape latency time from light compartment placement to entry into the dark compartment was recorded. Values shown are the mean latency ± SEM. Significant differences indicated by ###p < 0.001 vs. the control group and *p < 0.05 and ***p < 0.001 vs. the scopolamine-treated group.

Fig. 2. Effects of betulin and BPB on the scopolamine-induced amnesic mice in the Morris water maze test.

Notes: During acquisition trials using a submerged platform in the Morris water maze test, escape latency (A) and escape distance (B) of each mouse were monitored by a video-tracking system. Each day, mice were treated with betulin (5 mg/kg body weight, p.o.) and BPB (100 mg/kg body weight, p.o.). After 90 min of treatment, amnesia was induced by scopolamine injection (1 mg/kg body weight, s.c.). All mice were tested for spatial memory 30 min after scopolamine injection. Results significantly different from the values in trial 1 are indicated by *p < 0.05 and ***p < 0.001.

Fig. 3. The enhancing effects of betulin and BPB on spatial memory impairment induced by scopolamine in mice.

Notes: (A) Effects of betulin and BPB on scopolamine-induced memory deficit in the Y-maze test. Samples were administered orally to mice 60 min before the tests. (B) Effects of betulin and BPB during the probe trial of the Morris water maze test. Probe trial sessions were carried out for 60 s. Values are mean ± SEM. Significant differences indicated by ^###p < 0.001 and ^#p < 0.05 vs. the control group and *p < 0.05 vs. the scopolamine-treated group.

Table 1. The effects of betulin and betulinic acid on GSH levels in the hippocampus of scopolamine-injected mice.

	Total GSH (nmol/mg of protein)
Control	7.264 ± 0.660
Scopolamine	6.840 ± 1.026
Betulin 1 mg/kg	8.779 ± 0.448
Betulin 5 mg/kg	11.800 ± 0.784*
Betulin 10 mg/kg	10.694 ± 0.676*
Betulinic acid 5 mg/kg	9.065 ± 1.888

Note: GSH content was measured as described in materials and methods. Values represent the mean ± S.D. Values significantly different from the scopolamine group value are indicated by *p < 0.05 or **p < 0.01.