Immunomodulatory Effect Of Ginsenoside Rb1 (G-Rb1) On Experimental Autoimmune Myasthenia Gravis

Objective: To observe the effects of ginsenoside Rb1(G-Rb1) on experimental autoimmune myasthenia gravis(experimental autoimmune myasthenia gravis, EAMG) in rats and its mechanism.Methods: Adult female Lewis rats were randomly divided into G-Rb1 high dose group(3.7mg/kg/d), G-Rb1 low dose group(2.6mg/kg/d), model control group(EAMG group) and blank control group(CFA group). EAMG was induced by subcutaneous injections into both hind footpads of 200 ?l inoculum containing 50 ?g R97-116 peptide and 1mg mycobacterium tuberculosis and incomplete Freund's adjuvant, followed 10 days later with the same injection in the back. The rats were weighed every other day until day43 post immunization.The severity of the disease was scored by measuring muscular weakness in a blinded fashion. After 39 days,we use flow cytometry to detect the percentage of different groups of lymph node mononuclear cells(MNC) IL-10+, IL-4+,IL-17, MHC II+ cells and CD4+ CD25+ T cells and CD4+ CD25 + Foxp3 T cell; enzyme linked immunosorbent method(ELISA)was used to detect IgG / IgG1/ IgG2a/ IgG2 b of different groups;CCK-8 was used to detect proliferation of lymph node mononuclear.Results: 1) Ginsenoside Rb1 suppressed the severity of clinical EAMG.Both the low and high doses of Ginsenoside Rb1 suppressed the severity of EAMG. Rats treated with3.7 mg/kg/day Ginsenoside Rb1 exhibited significantly lower clinical scores compared with control rats on day days 10 to 42(p < 0.01each). and rats treated with 2.6mg/kg/day Ginsenoside Rb1 on days 10 to 34(p<0.05 each) and days 12 to 32(p<0.01each) and days 36 to 40(p < 0.01 each). Rats treated with2.6 mg/kg/day and 3.7mg/kg/day Ginsenoside Rb1 also had lower clinical scores than CFA group. 2)Rats treatedwith 3.7 mg/kg/day Ginsenoside Rb1 lighter than the EAMG group on days 26 and 27(p<0.05 each). Rats treated with 2.6 mg/kg/day Ginsenoside Rb1 weight than the EAMG group on days18 to 42(p < 0.05 each). 3) High doses of G- Rb1 can increase the percentages of IL-10 cells(P=0.026) and decrease IL-17 + cells(P=0.036).Both low and high doses of G- Rb1 treatment groups increased the percentages of CD4+CD25+ T cells and CD4+CD25+ Foxp3 T cells among lymph node MNC when compared with untreatedG-Rb(p < 0.05 each). 4) The low G-Rb1 group can significantly decrease IgG1 ? IgG2 a compared with control group(p=0.001,p=0.029,respectively). 5) Both high and low doses of G-Rb1 have therapeutic effects on EAMG. The experimental results show that the treatment with low dose of G-Rb1 has better effect on G-Rb1.Conclusion: High dose and low dose was subsequently treated can significantly reduce the clinical symptoms of myasthenia gravis in rats. The mechanism may and lower percentage of IL-17 +cells and Th2 and Treg cells increased, thereby reducing the anti r97-116 IgG1 and IgG2 a antibody level.