Anti-Inflammatory Effects of Fermented Products with Avena sativa on RAW264.7 and HT-29 Cells via Inhibition of Inflammatory Mediators

This study investigated therapeutic candidates with anti-inflammatory potential among traditional dietary ingredients targeting inflammatory bowel disease (IBD). Both Avena sativa and traditional fermented products, such as Korean soy paste, are popular health foods. We investigated the anti-inflammatory effects of soy paste combined with A. sativa (KDA), compared with soy paste without A. sativa (KD) by evaluating the expression of pro-inflammatory cytokines in lipopolysaccharide-stimulated RAW264.7 mouse macrophages and HT-29 human colon epithelial cells. KDA significantly inhibited the production of nitric oxide (NO) and downregulated the pro-inflammatory cytokines, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor-α in lipopolysaccharide (LPS)-induced RAW264.7 cells. In another in vitro experiment involving LPS-stimulated HT-29 cells, KDA suppressed the levels of IL-8, which is the chemokine elevated in IBD. In addition, KDA exhibited anti-oxidative properties, such as 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and 2,2'-azino-bis(3-ethylbenz-thiazoline-6-sulfonic acid) (ABTS) radical scavenging activity. Our findings revealed that A. sativa combined with soy paste exhibits a synergistic anti-inflammatory and anti-oxidant effect following fermentation. These results suggest that KDA may be used as a potential anti-inflammatory therapy against IBD.