Effect of water-soluble propolis on colonic motor function in rats with ulcerative colitis
Objective:To observe the alleviating effect of water-soluble propolis(WSP)on dextran sodium sulfate(DSS)induced ulcerative colitis(UC)in mice by measuring colonic tone and explore its possible mechanism.Methods:Twenty-four SPF C57 mice were randomly and equally divided into control group(CTRL group),dextran sodium sulfate group(DSS group),water-soluble propolis group(WSP group)and salicylazosulfapyridine group(SASP group).Except for the CTRL group,2.5％DSS was applied ad libitum in the mice in all groups for 7 days to induce an acute UC model.Disease activity index(DAI)and colon length were measured.Hematoxylin & eosin(HE)staining was performed to evaluate morphological changes of the colon.Enzyme-linked immunosorbent assay(ELISA)was used to detect the serum levels of pro-inflammatory cytokines interleukin-6(IL-6),interleukin-1 β(IL-1 β)and tumor necrosis factor alpha(TNF-α).The colonic tone and Ca2+dose-effect contraction were measured by PowerLab biological signal processing system.Results:Compared with the CTRL group,mice in the DSS group had lower body weight,higher DAI scores,shorter colon,significantly damaged colon mucosa,more inflammatory cell infiltration,higher serum levels of IL-6,IL-1β and TNF-α(P＜0.05),decreased muscle contractibility and increased contraction frequency(P＜0.01).The sensitivity to ACh and KCl stimulation and the Ca2+dose-effect contraction were decreased(P＜0.01).Compared with the DSS group,mice in the WSP group and SASP group had higher body weight,lower DAI scores,longer colon,less damaged colon mucosa and inflammatory cell infiltration,lower serum levels of IL-6,IL-1 β and TNF-α(P＜0.05),more normal contractibility and contraction frequency of colon smooth muscle(P＜0.01).Colon sensitivity to ACh and KC1 was increased and CaCl2 dose-effect contraction activity was enhanced(P＜0.01).Conclusion:The colon damage of DSS-induced acute UC mice is significant,with decreased contractibility and increased frequency,and CaCl2 dose-effect contraction activity is reduced.WSP can significantly alleviate colon damage in UC mice,possibly by lowering serum levels of pro-inflammatory cytokines,reducing intestinal mucosal damage,restoring their contractility and frequency,and thereby enhancing CaCl2 dose-effect contraction activity.
万方数据
维普
