Berberine ameliorates experimental autoimmune neuritis by suppressing both cellular and humoral immunity.

Berberine (BBR), an isoquinoline derivative alkaloid, has been extensively used in traditional Chinese medicine for the treatment of diarrhoea, rheumatic diseases, diabetes, etc. Recent studies have demonstrated new biological properties of BBR and suggested the possibility of BBR to be a therapeutic agent for some autoimmune diseases. To explore the effect of BBR on the development of experimental autoimmune neuritis (EAN), BBR was administered intragastrically daily to Lewis rats immunized with P0 peptide 180-199 in Freund's complete adjuvant. We found BBR treatment resulted in amelioration of EAN, accompanied by suppressed lymphocyte (in particular CD4(+) T cell) proliferation, downregulated Th1 (TNF-α) and Th2 (IL-10) cytokines and reduced anti-P0 peptide 180-199 IgG1 and IgG2a. In brief, BBR played a role in ameliorating EAN by suppressing both cellular and humoral immunity. Thus, our study suggests that BBR may be a potential therapeutic agent for the autoimmune disease in the peripheral nervous system, such as Guillain-Barré syndrome.