Effects of Berberine on Microglia and Cytokines in Rats with Experimental Autoimmune Encephalomyelitis

OBJECTIVE To explore the effects of berberine(Ber) on experimental autoimmune encephalomyelitis(EAE) and the changes of the levels of microglia, IFN-γ, TNF-α and IL-10 in spinal cord. METHODS Twenty four Lewis rats were randomly divided into three groups: control group, model group and Ber group. The change of activated microglia which expressing iba1 in lumbar cords was counted by immunohistochemistry. Expression levels of IFN-γ, TNF-α and IL-10 in serum and cervical cord were quantified by ELISA. RESULTS Eight rats in model group completely showed neurological signs of typical EAE. However, only three rats in Ber group demonstrated neurological signs of typical EAE. ELISA analysis showed that the expression of IFN-γ and TNF-α decreased significantly in the serum in Ber group compared with model group(P<0.05), IL-10 expression was not changed significantly. Immunohistochemical results showed that the active number of microglia was significantly inhibited in Ber group compared with the model group(P<0.05). Tissue ELISA analysis showed that the expression of IFN-γ and TNF-α decreased significantly(P<0.05), and the expression of IL-10 increased in the spinal cord in Ber group compared with model group(P<0.05). CONCLUSION Ber has an effect on prevention on occurence of EAE in Lewis rats, may be related to inhibition of microglia activation and downregulation of IFN-γ, TNF-α expression and upregulation of IL-10.