P078 Walnut extract ameliorates acute and chronic colitis in murine models of colitis
S.-J. Koh*, K. L. Lee, J.W. Kim, B. G. Kim, Y. J. Jung
Seoul National University Boramae Hospital, Seoul National University College of Medicine, Internal Medicine, Seoul, South Korea
Walnut (Juglans regia) is known to have anti-cancer and immunomodulatory effects. However, little information is available on the effect of walnut extract on acute and chronic murine colitis.
In the acute colitis model, mice were given 4% dextran sulfate sodium (DSS) for 5 days. Walnut extract (ie, 5 mg/kg/day and 20 mg/kg/day) was dissolved in PBS and administered once daily by oral gavage, beginning 2 days before DSS administration. To evaluate the disease activity index (DAI), body weight, stool consistency, and the presence of bloody stool or blood around the anus were assessed daily by a researcher. Postmoterm, a quantitative evaluation for histology was performed. Immunohistochemical stainings for phospho-IκB kinase (IKK) and occludin were performed in mouse colon tissue. In the chronic colitis, interleukin (IL)-10-/- mice were administered with either the vehicle or walnut extract (20 mg/kg) by oral gavage daily for 2 weeks.
Severe colitis was induced by DSS administration for 5 days. In contrast, administration of walnut extract significantly reduced the severity of DSS-induced murine colitis, as assessed by the disease activity index and colon length. In the histopathological analysis, histological grading showed that walnut extract significantly reduced overall colitis score in comparison to the scores of the PBS-treated controls. Immunohistochemical analysis showed that the DSS-induced phospho-IKK activation in intestinal epithelial cells was significantly decreased in walnut extract–treated mice. In addition, immunoreactivity for occludin was significantly inhibited by the treatments of walnut extract. Finally, walnut extract significantly reduced the severity of chronic colitis in IL-10-/- mice.
Walnut extract ameliorates acute and chronic colitis in mice, which suggest that walnut extract may have potential for the treatment of inflammatory bowel disease.