Icariin Inhibits Intestinal Inflammation of DSS-Induced Colitis Mice Through Modulating Intestinal Flora Abundance and Modulating p-p65/p65 Molecule

Turk J Gastroenterol. 2021 Apr;32(4):382-392. doi: 10.5152/tjg.2021.20282.

Abstract

Background: Ulcerative colitis, as a kind of inflammatory bowel disease (IBD) is characterized by abdominal pain. This study aimed to investigate the effect of icariin (ICA) on the intestinal microflora of colitis mice.

Methods: Fifteen female C57BL/6 mice were randomly divided into the Control group, dextran sodium sulfate (DSS)-induced colitis (DSS) group, and ICA treatment (DSS+ICA) group. The severity of inflammation in DSS-induced colitis mice was evaluated using disease activity scoring (considering weight-loss percentage, stool-shape change, and stool-bleeding scoring). Pathological changes of mice intestinal tract were evaluated using hematoxylin-eosin (HE) staining. Serum levels of TNF-α and IL-6 were detected with enzyme-linked immunosorbent assay. Expressions of p65 and p-p65 (p-p65/p65 ratio) were analyzed using Western blot assay. 16S rDNA sequencing was used to analyze the abundance and composition of intestinal microflora.

Results: Compared with DSS group, ICA significantly improved disease activity (P < .05) and reduced inflammatory damage of colon tissues (P < .05) in DSS-induced colitis mice. Compared with the DSS group, mice in the ICA group demonstrated significant weight and colon length (P < .05). ICA significantly inhibited expressions of IL-6 and TNF-α compared to the DSS group (P < .05). p-p65/ p65 ratio in the DSS + ICA group was remarkably enhanced compared to the DSS group (P < .05). ICA significantly reduced the proportion and activity of Bacteroides, Helicobacteraceae, Turicibacter, and significantly increased that of beneficial microflora (Lactobacillus, Lachnospiraceae, Akkermansia), so as improved damages of colon tissues.

Conclusion: ICA can improve intestinal flora abundance and composition of DSS-induced colitis mice, and inhibit tissue damage and inflammatory response through modulating the p-p65/p65 expression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Colitis / chemically induced
  • Colitis / drug therapy
  • Colitis, Ulcerative / chemically induced
  • Colitis, Ulcerative / drug therapy
  • Colon / drug effects*
  • Dextran Sulfate / toxicity*
  • Disease Models, Animal
  • Female
  • Flavonoids / pharmacology*
  • Gastrointestinal Microbiome*
  • Inflammation
  • Interleukin-6 / blood
  • Mice
  • Mice, Inbred C57BL
  • Tumor Necrosis Factor-alpha / blood

Substances

  • Flavonoids
  • Interleukin-6
  • Tumor Necrosis Factor-alpha
  • Dextran Sulfate
  • icariin

Grants and funding

This study was granted by the Natural Science Foundation of Jiangsu province [BK20180678], Project of “Nursing Science” Funded by the Priority Discipline Development Program of Jiangsu Higher Education Institutions (General Office, the People’s Government of Jiangsu Province [2018] No.87), Project of “Nursing Science” Funded by the Key Discipline Program of Jiangsu Province during the 13th five-year plan (Teaching and Research Office, the People’s Government of Jiangsu Province [2016] No.9).