Electroacupuncture ameliorates experimental colitis induced by TNBS through activation of interleukin-10 and inhibition of iNOS in mice

PURPOSE: To study the anti-inflammatory actions of electroacupuncture (EAc) on an experimental colitis model in mice. METHODS: Thirty-eight male Swiss mice, divided in five groups, were subjected to induction of colitis by TNBS in 50% ethanol. Saline (SAL) and ethanol (ETNL) groups served as controls. TNBS+EAc and TNBS+dexamethasone subgroups were treated with EAc 100Hz and dexamethasone (DEXA) 1 mg/Kg/day, respectively. After three days, a colon segment was obtained for quantification of myeloperoxidase (MPO) activity, immunohistochemistry for iNOS, malondialdehyde (MDA) and cytokines (IL-1 beta and IL-10). RESULTS: Neutrophilic activity, assayed as MPO activity, was significantly higher in the TNBS colitis group than that in the saline control group. TNBS+EAc group showed suppression of IL-10 in the colon. EAc treatment significantly reduced the concentration of MDA and the expression of iNOS, as compared to the other groups. CONCLUSION: Electroacupuncture 100Hz applied to acupoint ST-36 promotes an anti-inflammatory action on the TNBS-induced colitis, mediated by increase of IL-10 and decrease of iNOS expression.