Study On Immune Regulation Of Rabdosia Rubescens And Its Safety Assessment

Objective:To explore the immune regulatory function of Rabdosia rubescens and its safety, so that Rabdosia rubescens will be further developed as a health food in improving human immunological function.Methods:After the mice were orally administrated aqueous extract of Rabdosia rubescens at the doses of 18.33,36.67, 110.00ml/kg.bw for 30 days, the effects of Rabdosia rubescens on cellular,humoral immunologic functions and non-specific immune system were assessed by delayed-type hypersensitivity test (DTH), lymphocyte transformation method, hemolytic plaque assay, hemolysin assay, carbon clearance test, peritoneal macrophage phagocytosis function test and natural killer (NK) cell assay in mice.The safety of Rabdosia rubescens was comprehensively evaluated by acute toxicity test, mouse bone marrow cell micronucleus test and sperm malformation test in mice, Ames test and 90-day feeding study in rats.Results:In the experiments for assessment of enhancing immune function,The metatarsals swelling extents of mice treated with aqueous extract of Rabdosia rubescens in medium and high dose groups were significantly larger than that of control group.The number of antibody forming cells in medium and high dose groups and NK cell activity in medium dose group increased significantly.In the experiments for toxicological assessment of Rabdosia rubescens,Maximum Tolerated Dose(MTD) was greater than 20304mg/kg-bw in the male and female mice.The genotoxicity of Rabdosia rubescens was not observed in Ames test, bone marrow cell micronucleus test and sperm malformation test. The result of90-day feeding test showed that there were no treatment-related adverse effects on mice treated with Rabdosia rubescens and its No-observed-adverse-effect-level(NOAEL) was 5.000g/kg·bw.Conclusions:1.The aqueous extract of Rabdosia rubescens (the doses of 36.67 to 110.00ml/kg.bw)can enhance immunologic function in mice.2.The degree of the acute toxicity of Rabdosia rubescens is nontoxic according to the acute toxicity classification standard.3.The mutation tests show that the genotoxicty is negative.4.According to the results of sub-chronic toxicity test,Rabdosia rubescens is safe for health basically.