Abstract: Objective To investigate the effect of ginsenoside Rg1 on the spleen structure and function of aging rats and its relative mechanism.Methods 40 SD rats were randomLy divided into normal control group, aging model group (D-galactose 120 mg/kg,qd×42d), Rg1 intervention group（D-galactose 120 mg/kg,qd×42d and Rg1 20 mg/kg, from day 15th,qd×28d) and Rg1 control group (saline and Rg1 20 mg/kg,from day 15th,qd×28d) . After finishing injections ,the spleen index were measured, paraffin section were made to observe spleen microscopic structure. Senescence-accociated β-galactosidase(SA-β-Gal) stain was detected aging splenocytes. The proliferative capacity of splenocytes stimulated with Concanavalin A (ConA) was measured by CCK-8. The content of IL-2,IL-6 and advanced glycosylation end products(AGEs) were detected by ELISA. The levels of ROS was analyzed by flow cytometry(FCM). Malondialdehyde(MDA), superoxide dismutase (SOD) were detected by enzymatic assay. The expression of senescence-accociated protein P53,P21 and RB were detected by Western blot analysis. Results Comparing the Rg1 intervention group with the aging model group, spleen index, splenic white pulp area proportion, the proliferative capacity of splenocytes were significantly increased (P<0.05);The secretory capability of IL-2 and IL-6, the active content of SOD were obviously increased(P<0.01);The percentage of SA-β-Gal positive splenocytes, the production of ROS and MDA were significantly decreased (P<0.01);The production of AGEs was decreased (P<0.05);The expression of P53,P21 and Rb was also significantly down-regulated (P<0.01).Conclusion Ginsenoside Rg1 relieves injure of the spleen in aging rats induced by D-galactose.It is suggested that the mechanism may be Rg1 inhibiting oxidative stress and down-regulating P53-P21-RB signaling pathway.

Key words: ginsenoside Rg1, aging model , spleen , rat