ABSTRACT
Objective To investigate the effect of cysteine protease inhibitor derived from S chistosoma japonicum(SjCys-tatin)on dextran sodium sulfate(DSS)-induced acute ulcerative colitis in mice.Methods Eighteen C57BL/6 mice were ran-domly divided into three groups:a control group treated with PBS(Group A),a DSS-induced-colitis group treated with PBS(Group B),and a DSS-induced-colitis group treated with SjCystatin(Group C).Colitis was induced in mice by giving 3％DSS orally for 7 days.During this period,the mice were daily injected with 10μg of SjCystatin or PBS only as a control intraperitone-ally.The mice were monitored daily for their clinical manifestations and given scores based on disease activity index(DAI).The severity of colonic inflammation was monitored by the macroscopic score and pathological change.The cytokine profile including TNF-α,IL-4,IL-6 and IL-10 in the supernatants of colon homogenate was detected by ELISA.Results Compared with Group A(0.50 ± 0.28),the DAI score increased significantly in Group B(9.30 ± 1.30)(F=86.86,P<0.01),with remarkable path-ological damages seen in colon tissues.and the levels of TNF-α and IL-6 were(321.33±67.01)and(403.58 ±180.51)pg/mL.The DAI score significantly reduced in Group C(6.67±1.57)as compared to Group B(F=86.86,P<0.01),with improve-ments in the macroscopic and microscopic pathology in mouse colon specimens.As compared to Group B,the levels of TNF-α [(188.14 ± 40.14)pg/mL] and IL-6 [(209.71 ± 48.47)pg/mL] significantly decreased(F=17.46 and 9.89,both P<0.01).Con-clusion SjCystatin has a significantly inhibitory effect for alleviating DSS-induced acute ulcerative colitis in C57BL/6 mice.