Atractylenolide Ⅲ maintains Th17/Treg balance by inhibiting STAT3 signaling in a mouse model of chronic inflammatory bowel disease
AIM:To investigate the potential of atractylenolide Ⅲ(AⅢ)in mitigating dextran sulfate sodium(DSS)-induced injury in a mouse model of chronic inflammatory bowel disease(IBD),and to explore the mechanisms in-volved,particularly the modulation of signal transducer and activator of transcription 3(STAT3)signaling,which plays a crucial role in the homeostasis of T helper 17(Th17)and regulatory T(Treg)cells.METHODS:A mouse model of DSS-induced chronic IBD was established,and the mice were divided into 4 groups:control,model(DSS),high-dose(50 mg/kg)AⅢ,and low-dose(30 mg/kg)AⅢ.The disease activity index(DAI)was utilized to assess disease severity.Histo-pathological damage in the colons of IBD mice was evaluated by hematoxylin-eosin(HE)staining.The protein levels of phosphorylated STAT3,occludin and zonula occludens-1(ZO-1)were analyzed using immunohistochemical staining and Western blot.Flow cytometry was employed to examine the differentiation of splenic lymphocytes into Th17/Treg cells.RESULTS:Both DAI assessments and HE staining indicated that AⅢ significantly alleviated inflammatory injury in mice with DSS-induced chronic IBD.Immunohistochemical analysis demonstrated that AⅢ enhanced the expression of ZO-1 and occludin in colonic tissues.Flow cytometry results revealed that AⅢ helped maintain the balance between splenic Th17 and Treg cells.Furthermore,immunohistochemical staining and Western blot showed that AⅢ inhibited the phos-phorylation of STAT3.CONCLUSION:Treatment with AⅢ effectively reduced inflammatory injury in a mouse model of chronic IBD by preserving Th17/Treg homeostasis through the inhibition of STAT3 phosphorylation.As a natural com-pound,AⅢ exhibits significant therapeutic potential for the treatment of chronic IBD.