Abstract: Objective: To observe whether schisandrin B (SCB) can improve D-galactose-induced learning and memory impairment in aging mice. Methods: ICR mice were randomly divided into normal control group (intragastrically administered with distilled water and subcutaneously injected with normal saline), aging model group (intragastrically administered with distilled water and subcutaneously injected with 220 mg/kg D-galactose), SCB (M) group (intragastrically administered with 20 mg/kg SCB and subcutaneously injected with 220 mg/kg D-galactose), and SCB (C) group (intragastrically administered with 20 mg/kg SCB and subcutaneously injected with normal saline). The administration lasted for 7 weeks. Step-through test and Morris water maze test were applied to observe the effect of SCB on the learning and memory capacity of mice. The superoxide dismutase (SOD) activity in the brain tissue of mice was detected by the WST-1 method and the malondialdehyde (MDA) content was measured by the TBA method. The mRNA and protein expression of p19, p53 and p21 genes were detected by quantitative real-time PCR and Western blot, respectively. Results: SCB could significantly improve the learning and memory ability of D-galactose-induced aging mice, increase the SOD activity in the brain tissue, decrease the MDA level, and reduce the expression of p19, p53 and p21 genes. Conclusion: SCB can improve brain aging induced by D-galactose in mice, and the mechanism may be related to the increased antioxidant capacity and the decreased expression of p19, p53 and p21 genes in the brain tissue of mice.

Key words: schisandrin B, amelioration of age-associated memory impairment, p19 gene, p53 gene, p21 gene