[#2010-07] Grifola frondosa ( Maitake ) water extract alleviates intestinal inflammation by suppressing TNF-α production and its signaling, Jong Suk Lee et al.
Grifola frondosa ( Maitake ) water extract alleviates intestinal inflammation by suppressing TNF-α production and its signaling
Jong Suk Lee1*, Su-Young Park1*, Dinesh Thapa1, Mi Kyoung Choi1, Ill-Min Chung2, Young-Joon Park3, Chul Soon Yong1, Han Gon Choi1 and Jung-Ae Kim1
1College of Pharmacy Yeungnam University, Korea 2College of Life and Environmental Sciences Konkuk University Seoul, Korea 3Research Center Samil Pharmaceutical Co. Ltd. Korea
Abstract
TNF-α is a major cytokine involved in inflammatory bowel disease (IBD). In this study, water extract of Grifola frondosa (GFW) was evaluated for its protective effects against colon inflammation through the modulation of TNF-α action. In coculture of HT-29 human colon cancer cells with U937 human monocytic cells, TNF-α induced monocyte adhesion to HT-29 cells was significantly suppressed by GFW (10, 50, 100 ìg/ml). The reduced adhesion by GFW correlated with the suppressed expression of MCP-1 and IL-8, the major IBD-associated chemokines. In addition, treatment with GFW significantly suppressed TNF-α-induced reactive oxygen species production and NF-kB transcriptional activity in HT-29 cells. In differentiated U937 monocytic cells, LPS-induced TNF-α production, which is known to be mediated through NF-kB activation, was significantly suppressed by GFW. In an in vivo rat model of IBD, oral administration of GFW for 5 days (1 g/kg per day) significantly inhibited the trinitrobenzene sulfonic acid (TNBS)-induced weight loss, colon ulceration, myeloperoxidase activity, and TNF-α expression in the colon tissue. Moreover, the effect of GFW was similar to that of intra-peritoneal injection of 5-aminosalicylic acid (5-ASA), an active metabolite of sulfasalazine, commonly used drug for the treatment of IBD. The results suggest that GFW ameliorates colon inflammation by suppressing production of TNF-α as well as its signaling through NF-kB leading to the expression of inflammatory chemokines, MCP-1 and IL-8. Taken together, the results strongly suggest GFW is a valuable medicinal food for IBD treatment, and thus may be used as an alternative medicine for IBD.
