RESUMO
The aim of the present study was to investigate the therapeutic effect of Pulsatilla decoction (PD) on ulcerative colitis (UC) and to elucidate its potential molecular mechanisms. C57BL/6 mice expressing natural killer (NK)1.1 were used as experimental animals in the present study and a model of oxazoloneinduced colitis was established. Mice were randomly divided into the following five groups: i) PD group; ii) oxazoloneinduced colitis group; iii) IL13 intervention group; iv) 5aminosalicylic acid positive control group; and v) negative control group (equal volume saline gavage). A total of 10 animals were used in each group. The effects of PD on UC and the association between this regimen and the PI3KAktmTORC1 signaling pathway were evaluated by disease activity index (DAI), hematoxylin and eosin staining, reverse transcriptionquantitative PCR (RTqPCR), immunofluorescence assay, ELISA and western blotting. The UC models were successfully established by injecting oxazolone gavage solution. Clinical colitis evaluation and histological examination revealed that PD reduced the DAI values in oxazoloneinduced colitis in mice and the degree of infiltration in NK1.1 cells. PD significantly reduced the secretion of IL13, as determined using an ELISA. In addition, western blotting and RTqPCR analyses demonstrated that Beclin1 and LC3II/I expression levels were downregulated following treatment of the mice with PD. In addition, PD not only partially restored alterations in the expression of tight junction proteins in the colon tissues, but also suppressed the activation of the PI3KAktmTORC1 signaling pathway. The data indicated that this regimen could alleviate oxazoloneinduced UC in mice, which could significantly reduce tissue inflammation and autophagy. The mechanism of action was associated with the PI3KAktmTORC1 signaling pathway.