Effects of Earthworm Extracts on Dextran Sulfate Sodium-induced Ulcerative Colitis in Mice

Purpose To investigate the effects of earthworm extracts on the dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice, providing experimental evidence for earthworm extracts as potential therapeutic drugs for UC.

Methods C57BL/6 mice drank 3.5% DSS solution freely for seven days and gavaged with different concentrations of earthworm extracts. The psychosis body weight, and stool characteristics were monitored daily. Dissection was performed on the 10th day, and the spleen and colon were sampled. Colon pathological sections were made by hematoxylin-eosin staining, and the mRNA expression level of tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), interleukin 1β (IL-1β) and interleukin 10 (IL-10) were detected by qRT-PCR; zonula occludens protein 1 (ZO-1), mucin 2 (Muc2), and occludin protein expression in colon tissue was detected by ELISA.

Results The earthworm extracts reduced body weight loss, disease activity index score and the degree of inflammatory cell infiltration in mice, down-regulated the mRNA expression level of IL-6, IL-1β and TNF-α, and up-regulated the mRNA expression of IL-10 and the protein expression of ZO-1, occludin and Muc2.

Conclusion Earthworm extract has a relieving effect on DSS-induced UC in mice, relieved the inflammatory damage of colon tissue and the symptoms of UC, protecting the integrity of the colonic mucosa and improving the intestinal mucosal barrier function.