Curcumin regulated shift from Th1 to Th2 in trinitrobenzene sulphonic acid-induced chronic colitis

AIM: To investigate the therapeutic effects of curcumin (Cur) on trinitrobenzene sulphonic acid (TNBS)-induced colitis and the effects of Cur on the balance of Th1/Th2 cytokines. METHODS: Colitis was induced by TNBS and treated with Cur (30 mg/kg/d, ip), dexamethasone (Dex, 2 mg/kg/d), or Cur plus dexamethasone (Cur+Dex, 30 mg/kg/d Cur ip+2 mg/kg/d Dex,ip). mRNA in colon mucosa were detected by real-time quantitative polymerase chain reaction. Intracellular cytokines were detected by flow cytometry and concentrations of cytokines in sera were detected by enzyme-linked immunosorbent analysis. RESULTS: Both Cur and Dex improved body weight loss, ameliorated histological images and decreased macroscopic score and myeloperoxidase activity. Cur decreased the expression of Th1 cytokines (IL-12, IFN-gamma, TNF-alpha, IL-1) and increased the expression of Th2 cytokines (IL-4 and IL-10) in colon mucosa. Cur also increased the proportion of IFN-gamma/IL-4 in splenocytes and circulation. Dex and Cur+Dex decreased the expression of Th1 cytokines but could not increase the expression of Th2 cytokines and the proportion of IFN-gamma/IL-4. CONCLUSION: Cur exerted therapeutic effects on colitis by regulating the shift from Th1 to Th2.