Abstract: OBJECTIVE: To investigate the effect of Banxia Xiexin decoction(BXD) on Helicobacter pylori(Hp)-related peptic ulcers(PUs) and the possible mecha-nism underlying BXD actions via the transforming growth factor-β/small mothers against decapentaplegic(TGF-β/Smad) signaling pathway.METHODS: PU patients with cold-heat complex syndrome were randomly assigned to groups that received Chinese or Western medicines with 20 patients in each group. Serum was collected after 7 d of treatment. The healthy group included 20 individuals. Gastric mucosal epithelial cell line GES-1 was cultured in vitro and randomly divided into the following seven groups: control, model, healthy,Western Medicine, prior treatment, low dosage,and high dosage. After 72 h of treatment with the corresponding serum, the m RNA and protein expression levels of TGF-β1, Smad3, and Smad7 were measured by reverse transcription quantitative polymerase chain reaction and western blotting, respectively.RESULTS: The m RNA expression levels of TGF-β1 and Smad3 in GES-1 cells were increased after Hp introduction, and these increased levels were reduced by the BXD-containing serum. The protein levels of p-Smad3, but not TGF-β1 or Smad3, were significantly increased in Hp-treated GES-1 cells,and treatment with the BXD-containing serum markedly decreased the protein levels. Smad7 expression was significantly enhanced following treatment with the BXD-containing serum at transcriptional and protein levels in a dose-dependent manner.CONCLUSION: BXD regulates the TGF-β/Smad signaling pathway by inhibiting the expression of TGF-β1 and Smad3, and increasing the expression of Smad7.

Key words: Helicobacter pylori, Peptic ulcer, Transforming growth factor beta, Smad proteins, Banxia Xiexin decoction, human drug-containing serum