摘要

Background and Objective: Astragaloside IV, the main bioactive ingredient of Radix Astragali showed anti-inflammation and would healing effect in practice. This study aimed to investigate the therapeutic effect of astragaloside IV (AS-IV) on experimental colitis as well as its role in mucosal healing and barrier function. Materials and Methods: TNBS-induced colitis rats were orally treated with AS-IV at the dose of 10,20 and 40 mg kg(-1) per day for 8 consecutive days. After drug treatment, histological damage score and myeloperoxidase activity of the colon tissue were detected, mucosal barrier function was evaluated by measuring the serum level of D-lactate and diamine oxidase and colonic goblet cells and the mRNA expression of Mucin were also evaluated by immuno-histochemistry and RT-PCR, respectively. The proteins and genes in Wnt and Notch signaling were further investigated by Western blot and RT-PCR to identify the effect of AS-IV on the differentiation of goblet cells. Results: Histological scores, myeloperoxidase activity and serum level of D-lactate and diamine oxidase in colitis rats were significantly increased, while mRNA expression of Muc-2 and Muc-3 were significantly decreased. AS-IV administration significantly reduced histological scores, myeloperoxidase activity and the level of D-lactate and diamine oxidase in colitis rats and the expression of Muc-2 and Muc-3 were markedly increased. Moreover, the protein expression in Wnt signaling, i.e., Lrp5, Lrp6 and beta-catenin, in the colon of colitis rats was significantly elevated, but the genes expression in Notch signaling, i.e., Rath1, Gfi1 and Klf4, in colitis rats were markedly decreased, and these alteration of Wnt and Notch signaling in colitis rats were markedly reversed by AS-IV administration. Conclusion: AS-IVattenuates colon inflammation in colitis rats via improving mucosal barrier function, the regulatory effect on the proliferation and differentiation of goblet cells may contribute to the therapeutic role of AS-IV in colitis.

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