Anti-inflammatory effects of Huangqin tang extract in mice on ulcerative colitis

Abstract

Ethnopharmacological relevanceHuangqinTang (HQT) is a traditional Chinese formula which is composed of Scutellaria baicalensis Georgi, Paeonia lactiflora Pall, Glycyrrhiza uralensis Fisch, and Ziziphus jujube Mill. HQT has been used in China for a wide range of disorders, especially in gastrointestinal inflammation with symptoms of nausea, vomiting, diarrhea, abdominal cramps and so on. Aim of the studyTo investigate the protective effects of HQT extract on 2, 4, 6-trinitrobenzenesulfonic acid (TNBS) induced colitis in mice. Materials and methodsDifferent doses of HQT extract (1, 2 and 4g/kg/day) and salicylazosulfapyridine (SASP, 500mg/kg/day) were administered by gavage for 7 days after the induction of colitis with TNBS. The effects were studied by macroscopic score, histological analysis, immunohistochemical study of Cyclo-oxygenase-2 protein expression, as well as by determination of inflammation markers such as myeloperoxidase (MPO) and mRNA expression levels of pro-inflammatory cytokines, including TNF-α, IL-1β and IL-6. ResultsIn TNBS induced group, mice body weight decreased gradually and did not recover at the end of the experiment, as compared with that of control group (p<0.01). Edema and redness were also discovered in the colons profoundly and scores representing inflammation were all high in this group (p<0.01). The level of colonic MPO activity and the tissue levels of TNF-α, IL-1β and IL-6 were markedly increased (p<0.01). The mice treated with HQT extract and SASP recovered significantly compared with the TNBS group (p<0.01). ConclusionOur results suggested that the efficacy of HQT extract, especially at the higher dose, was analogous to that of SASP, which implicated its potential application as a natural alternative medicine in colitis treatment.