A new rat model of chronic relapsing ulcerative colitis with traditional Chinese medicine syndrome of yang deficiency and dampness stagnation

Abstract

IntroductionChronic relapsing ulcerative colitis (CRUC) is classified as an inflammatory bowel disease, and traditional Chinese medicine (TCM) has been recognized for its therapeutic benefits in treating CRUC. According to TCM principles, the prevailing syndromes in CRUC are yang deficiency and dampness stagnation (YDDS). The objective of this study is to establish a novel animal model of CRUC exhibiting the YDDS syndrome. MethodsInitially, the rats were administered hydrocortisone succinate sodium through subcutaneous injection, followed by the administration of senna folium granule solution. Subsequently, the rats underwent three cycles of dextran sulfate sodium solution ingestion. ResultsUpon completion of the modeling process, it was observed that the disease activity index, colonic mucosal damage index score, colon weight/length ratio, colonic histopathology score, and tissue damage index scores of the model rats were elevated, while the colon length and spleen index exhibited a decrease compared to the control group. The pathological alterations in the model rats included the presence of shallow or deep ulcers and acute or chronic inflammation throughout the process of CRUC modeling. Additionally, our findings indicate a correlation between the proximity of the ulcer to the anal verge, the severity of the lesion, and the presence of precancerous glands, glandular disappearance, crypt abscesses, and tissue destruction. Furthermore, the expression levels of IL6, IL10, IFNG, and TNFA in the colon tissues were significantly elevated in the model rats compared to the control group. Notably, the end-stage lesions observed in CRUC exhibited greater severity when compared to those observed in cases of acute ulcerative colitis. DiscussionIn conclusion, we have successfully developed a rat model of CRUC with YDDS syndrome, which can be utilized to investigate the effectiveness and underlying mechanisms of TCM in treating CRUC.