BBI inhibits LPSinduced expression of inflammatory cytokines in intestinal epithelial cells

Abstract:

ObjectiveTo investigate the inhibitory effect and mechanism of soybeanderived BowmanBirk inhibitor (BBI) on LPSinduced expression of inflammatory cytokines in intestinal epithelial cells.MethodsCytotoxicity effect of LPS and BBI on intestinal epithelial cells was analyzed by MTT assay. Intestinal epithelial cells were pretreated with BBI, followed by LPS stimulation, expression of inflammatory cytokines（TNFα, IL1β, IL8, and MCP1） was detected by quantitative realtime polymerase chain reaction; the activation of NFκB was measured by pNFκBluc system and Western Blot.ResultsThe maximum concentration of LPS（10 000 ng/mL） and  BBI（1 000 μg/mL）had no cytotoxicity effect on intestinal epithelial cells. LPS could potently upregulate the expression of inflammatory cytokines（TNFα, IL1β, IL8, and MCP1）, the upregulation was positively correlated to the concentration of LPS; LPSinduced expression of inflammatory cytokines in intestinal epithelial cells could achieve the highest level, then decreased over time. The upregulation of LPS on inflammatory cytokines in intestinal epithelial cells had dosetime effect; when intestinal epithelial cells were pretreated by BBI for 6 hours, the inhibitory effect of BBI on LPSinduced expression of inflammatory cytokines in intestinal epithelial cells was most obvious, and had dosetime effect.ConclusionBBI can potently inhibit LPSinduced expression of  inflammatory cytokines through inhibiting NFκB in intestinal epithelial cells.