Objective:To evaluate the effects of Huangqin Tang on the IL-23/IL-17 pathway in 2

4

6-trinitrobenzene sulfonic acid(TNBS)-induced colitis model. Method: SD rats were distributed into four group

containing TNBS-induced colitis

Huangqin Tang(1.2 g·kg-1) or mesalazine treatment group(10 mL·kg-1

ig)

negative control with no treatment and the last one was normal sham rats. Except for control group

experimental colitis was induced by rectal instillation of 2

4

6-trinitrobenzene sulfonic acid (TNBS) into rats. Drugs were given intragastrically for one week in each group continuously according to respectively-designed doses. The protein expressions of IL-17 and IL-23 in serum were determined by ELISA. The mRNA expressions of IL-17

IL-23

IL-17R

IL-23R and RORγt were determined by Real-time PCR. Result: Huangqin Tang markedly attenuated TNBS-induced colitis and effectively inhibited the protein expressions of IL-17(262.75±17.19) ng·L-1 and IL-23(56.75±6.20) ng·L-1. Furthermore

mRNA levels of IL-17(2.606±0.8)

IL-17R(5.33±1.10)

IL-23(2.16±0.19)

IL-23R(3.34±0.70)

RORγt(0.74±0.17)showed a marked reduction after Huangqin Tang teatment. Conclusion: Taken together

our findings demonstrate that Huangqin Tang can exerte therapeutic effects on TNBS-induced colitis

mediate probably by the IL-23/IL-17 pathway.