Leonurine protects against ulcerative colitis by alleviating inflammation and modulating intestinal microflora in mouse models

Exp Ther Med. 2021 Nov;22(5):1199. doi: 10.3892/etm.2021.10633. Epub 2021 Aug 23.

Abstract

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the colon. The aim of the present study was to explore the effects of leonurine (YMJ) on inflammation and intestinal microflora in colonic tissues of a dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mouse model. Mice were randomly divided into control (n=5), DSS (n=5, treated with DSS) and DSS+YMJ (n=5, treated with DSS and YMJ) groups. Body weight was recorded, disease activity index (DAI) was calculated, and colon histopathology was evaluated using hematoxylin and eosin staining. Serum interleukin (IL)-6, tumor necrosis factor-α (TNF-α) and IL-1β levels were examined using ELISA. Expression levels of nuclear factor-κB (p65) and phosphorylated (p)-p65 were evaluated via western blotting. 16S ribosomal RNA was extracted from mouse feces. Composition or abundance changes of intestinal microflora were analyzed. The results indicated that YMJ treatment (DSS+YMJ group) significantly increased body weight, reduced DAI scores and increased colon length in UC mouse models compared with those in the DSS group (P<0.05). YMJ significantly reduced inflammatory infiltration, significantly decreased serum TNF-α, IL-6 and IL-1β levels (P<0.05) and significantly downregulated the p-p65/p65 ratio compared with the DSS group (P<0.05). YMJ increased the quantity of the intestinal flora and improved intestinal microflora diversity in the mice of the DSS group. Specifically, YMJ partly regulated intestinal microflora in feces, including a reduction of Bifidobacterium, and an increase in Parasutterella and Ackermania. In conclusion, YMJ improved disease outcomes of the UC mice, reduced the levels of serum inflammatory factors and increased the ratio of beneficial bacteria in the intestinal tract.

Keywords: inflammatory bowel disease; intestinal microflora; leonurine; ulcerative colitis.

Grants and funding

Funding: This work was funded by the Natural Science Foundation of Jiangsu province (grant no. BK20180678), the Natural Science Foundation of Jiangsu Universities (grant no. 17KJB330004), Project of ‘Nursing Science’ Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (General Office, the People's Government of Jiangsu Province; grant no. [2018]-No. 87), the key discipline project of ‘Nursing Science’ of Jiangsu province during the 13th five-year plan (Jiangsu Provincial Primary and Secondary School Teaching and Research Office; grant no. [2016]-No. 9), ‘Nursing Science’ of Jiangsu University Brand Professional Construction Project (Jiangsu Colleges and Universities; grant no. [2015]-No. 11) and ‘Centre for Health Promotion and Nursing Cooperative Innovation’ Constructive Project of Nanjing Medical University (grant no. JX21831803/004).