Mechanism of Schisandrae Chinensis Fructus Lignans in Alleviating Learning and Memory Ability in D-galactose Aging Mice / 中国实验方剂学杂志

ABSTRACT

Objective:To study the effect of Schisandrae Chinensis Fructus lignans (SCL) on learning and memory ability of D-galactose（D-gal）-induced aging model mice. Method:ICR mice were randomly divided into 4 groups normal group (distilled water, subcutaneous injection with normal saline), model group (distilled water, subcutaneous injection with 200 mg·kg-1D-gal), piracetam group (oral administration with 200 mg·kg-1 piracetam, subcutaneous injection with 200 mg·kg-1D-gal), low-dose SCL group (oral administration with 50 mg·kg-1·d-1 SCL, subcutaneous injection with 200 mg·kg-1·d-1 D-gal), medium-dose SCL group (oral administration with 100 mg·kg-1·d-1 SCL, subcutaneous injection with 200 mg·kg-1·d-1D-gal), high-dose SCL group (oral administration with 200 mg·kg-1·d-1 SCL, subcutaneous injection with 200 mg·kg-1·d-1 D-gal). The drugs were administered continuously for 10 weeks. Dark test and Morris water maze test were performed to observe the effect of SCL on the learning and memory ability of D-gal-induced aging mice. The activities of superoxide dismutase (SOD) and malondialdehyde (MDA) in mouse brain tissue were detected by chemical colorimetry. The expressions of peroxiredoxin-6（Prdx6） and glutathione peroxidase 1（GSH-Px1） mRNA in mouse brain tissue were detected by polymerase chain reaction (PCR). The expressions of Prdx6 and GSH-Px1 protein in mouse tissues were detected by Western blot. Result:In behavioral experiments, compared with normal group, the number of dark avoidance errors in model group significantly increased (P<0.05), the latency was significantly reduced (P<0.01), and the number of mouse passes and the target quadrant residence time were significantly reduced (P<0.01), which can be used as an indicator of successful modeling. Compared with the model group, the number of errors in the piracetam group, and medium and high-dose SCL groups was significantly reduced (P<0.05，P<0.01), and the latency was significantly prolonged (P<0.05，P<0.01). At the same time, the number of water maze passes and the target quadrant retention time in the high-dose SCL group increased significantly (P<0.01). The results of biochemical indicators showed that compared with normal group, the SOD activity in brain tissue of model group mice was significantly reduced (P<0.01), while the MDA content was increased (P<0.05). Compared with the model group, SOD activity in the brain tissues of piracetam group, and low, medium and high-dose piracetam groups was significantly increased (P<0.05), whereas the level of MDA was reduced (P<0.05). The expressions of Prdx6 and GSH-Px1 were significantly increased (P<0.05，P<0.01), indicating that the SCL administration group was dose-dependent. Conclusion:SCL can improve the learning and memory ability of D-gal-induced aging mice, which may be related to the anti-oxidation ability of SCL and the up-regulation of Prdx6 and GSH-Px1 expressions in mouse brain tissue.