Annickia polycarpa extract attenuates inflammation, neutrophil recruitment, and colon damage during colitis

• Published in: Immunology letters 2022-08, Vol.248, p.99-108
• Main Authors: Lartey, Nathaniel L., Vargas-Robles, Hilda, Guerrero-Fonseca, Idaira M., Nava, Porfirio, Kumatia, Emmanuel K., Ocloo, Augustine, Schnoor, Michael
• Format: Article
• Language: English
• Subjects: E-cadherin; Inflammatory bowel diseases; Nutritional supplement; Reactive oxygen species; Ulcerative colitis; ZO-1
• ISSN: 0165-2478; 1879-0542
• DOI: 10.1016/j.imlet.2022.07.006

•Annickia polycarpa stem bark extract (APE) ameliorates experimental colitis.•APE reduces the production of inflammatory cytokines and chemokines.•APE fine-tunes neutrophil recruitment and oxidative stress.•APE helps maintain epithelial barrier functions during colitis.•APE is a promising nutritional supplement to improve acute and chronic colitis. Inflammatory bowel diseases (IBD) including Crohn's disease (CD) and ulcerative colitis (UC) are complex inflammatory disorders of the digestive tract. Dysfunctional intestinal epithelial barrier, uncontrolled neutrophil recruitment into the colon, and oxidative stress are major features of IBD. IBD cannot be cured, but symptoms can be alleviated with anti-inflammatory drugs, which often show adverse effects. Thus, safer alternative treatment options are needed. Given the known anti-inflammatory properties of Annickia polycarpa extract (APE), we hypothesized that APE improves the outcome of the inflammatory response during colitis. We assessed APE effects on colon histology, epithelial barrier function and neutrophil recruitment during DSS-induced colitis in mice treated with APE. APE treatment significantly reduced the disease activity index and prevented DSS-induced colon damage as evidenced by reduced colon shortening, ulcerations, crypt dysplasia, edema formation, and leukocyte infiltration. Expression of the pro-inflammatory cytokines TNF-α, IL-6, and IL-1β were significantly diminished in APE-treated mice. Importantly, APE administration reduced neutrophil infiltration into the lamina propria leading to reduced oxidative stress, tight junction disruption and epithelial permeability in the colon. Thus, we propose APE as additional treatment strategy to attenuate colitis symptoms and enhance life quality of individuals with IBD. Graphical Abstract showing the suggested mechanism of action of Annickia polycarpa extract on DSS-induced colitis in mice. APE improves the outcome of DSS-colitis in mice by attenuating the pro-inflammatory immune response, fine-tuning neutrophil influx into the colon mucosa, consequently reducing oxidative stress and epithelial hyperpermeability in the inflamed colon. [Display omitted]