Short-Chain Naphthoquinone Protects Against Both Acute and Spontaneous Chronic Murine Colitis by Alleviating Inflammatory Responses

Winnie Mice: A Chronic and Progressive Model of Ulcerative Colitis

Recent trends show a continuous worldwide rise in the incidence of ulcerative colitis (UC), leading to increased interest in its etiology and pathogenesis, which is currently unknown. To gain a better mechanistic understanding of this disease, many mouse models have been developed over the last several years, with variations of dextran sodium sulfate administration representing the most widely employed. The Winnie mouse strain was created through elicited random mutations in Muc2, resulting in a progressive, chronic intestinal inflammation localized to the colon that worsens over time. Moreover, Winnie mice display immunologic and microbiota features that are similar to those that can be found in UC patients. Phenotypically, the presence, albeit rare, of rectal prolapse and other complications impacting quality of life can be observed in Winnie mice, as well as extraintestinal manifestations that are often associated with UC. While Winnie mice are currently less studied compared to other more established models of colitis, much has been discovered in the initial years of its use as a UC-like model. In summary, the use of Winnie mice adds to the growing armamentarium that is required to develop precision-based medicine for its future application in treating complex multifactorial diseases, such as UC.

Benefit Effect of Dendrobium officinale Ultrafine Powder on DSS-Induced Ulcerative Colitis Rats by Improving Colon Mucosal Barrier

Materials and Methods

After intragastric administration of DOFP for 3 weeks, the rat UC model was made by the administration of 4% oral DSS solution for one week, and the drug was given at the same time. During the experiment, the disease activity index (DAI) score of the rats was regularly computed. At the end of the experiment, the blood routine indexes of rats were obtained. The histopathological changes in the colon were monitored by hematoxylin-eosin (H&E) and PAS staining and observation of ultrastructural changes in the colon by transmission electron microscope. Occludin expression in the colon was monitored by Western blot, the expression of claudin-1 and ZO-1 in the colon was detected by immunofluorescence, and the expression of TNF-α, IL-6, and IL-1β in the colon was detected by immunohistochemistry.

Results

The results firstly indicated that DOFP could significantly alleviate the signs and symptoms of the DSS-induced rats UC model, which manifested as improvement of body weight loss, increase of colon length, and improvement of the symptoms of diarrhea and hematochezia. Then, results from histopathology, blood routine examination, and transmission electron microscope analysis further implied that DOFP could dramatically reduce inflammatory cell infiltration and restore intestinal epithelial barrier integrity. In addition, the experiments of Western Blot analysis, immunofluorescence, and PAS staining also further confirmed that DOFP could markedly increase related protein expressions of the intestinal barrier and mucus barrier, as the expression of occludin, claudin-1, and ZO-1 in the colon significantly decreased. The experiments of immunohistochemistry confirmed that DOFP could markedly decrease protein expression levels of inflammatory cytokines TNF-α, IL-6, and IL-1β.

Conclusion

DOFP notably alleviated inflammatory lesions, repaired the colon mucosa damage by promoting the expression of tight junction proteins occludin, claudin-1, and ZO-1 and inhibiting the release of inflammatory factors TNF-α, IL-6, and IL-1β, and finally achieved the purpose of treating UC.