TRPV1 participates in the protective effect of propolis on colonic tissue of ulcerative colitis

• Published in: Zhong nan da xue xue bao. Journal of Central South University. Yi xue ban 2023-02, Vol.48 (2), p.182-190
• Main Authors: Wang, Jing, Qian, Zhen, Lu, Taiyu, Li, Ruirui, Li, Hui, Zhang, Hao, Sun, Li, Wang, Haihua
• Format: Article
• Language: chi ; eng
• Subjects: Animals; Antineoplastic Agents - therapeutic use; Colitis, Ulcerative - chemically induced; Colon - pathology; Disease Models, Animal; Interleukin-6 - pharmacology; Male; Propolis - therapeutic use; Rats; Rats, Sprague-Dawley; Sulfasalazine - therapeutic use; TRPV Cation Channels; Tumor Necrosis Factor-alpha - pharmacology
• ISSN: 1672-7347
• DOI: 10.11817/j.issn.1672-7347.2023.220426

Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) mainly characterized by inflammation, ulceration and erosion of colonic mucosa and submucosa. Transient receptor potential vanilloid 1 (TRPV1) is an important mediator of visceral pain and inflammatory bowel disease. This study aims to investigate the protective effect of water soluble propolis (WSP) on UC colon inflammatory tissue and the role of TRPV1. Male SD rats were randomly divided into 6 groups ( =8): a normal control (NC) group, an ulcerative colitis model (UC) group, a low-WSP (L-WSP) group, a medium-WSP (M-WSP) group, a high-WSP (H-WSP) group, and a salazosulfapyridine (SASP) group. The rats in the NC group drank water freely, and the other groups drank 4% dextran sulfate sodium (DSS) solution freely for 7 d to replicate the ulcerative colitis model. Based on the successful replication of the UC, the L-WSP, M-WSP, and H-WSP groups were given 50, 100, and 200 mg/kg of water-soluble propolis by gavage for 7 d, and the SASP group was given 100 mg/kg of sulfasalazine by gavage for 7 d. The body weight of rats in each group was measured at the same time every day, the fecal traits and occult blood were observed to record the disease activity index (DAI). After intragastric administration, the animals were sacrificed after fasted 24 h. Serum and colonic tissue were collected, and the changes of MDA, IL-6 and TNF-α were detected. The pathological changes of colon tissues were observed by HE staining, and the expression of TRPV1 in colon tissues was observed by Western blotting, immunohistochemistry, and immunofluorescence. The animals in each group that drank DSS freely showed symptoms such as weight loss, decreased appetite, depressed state, and hematochezia, indicating that the model was successfully established. Compared with the NC group, DAI scores of other groups were increased (all