Anti‐inflammatory and immunomodulatory activities of stevioside and steviol on colonic epithelial cells

Abstract BACKGROUND Stevioside is a natural non‐caloric sweetener isolated from Stevia rebaudiana Bertoni leaves. We have proposed its effect on attenuation of tumour necrosis factor α ( TNF ‐α) and interleukin 1β ( IL ‐1β) release in lipopolysaccharide ( LPS )‐stimulated monocytes. In this study, the anti‐inflammatory and immunomodulatory activities of stevioside and its metabolite, steviol, on human colon carcinoma cell line (Caco‐2) were evaluated . RESULTS Stevioside and steviol, in the doses used in this study, had no cytotoxicity on Caco‐2 cells. Anti‐inflammatory activities of these two compounds were observed by potentially suppressed LPS ‐mediated TNF ‐α, IL ‐1β and IL ‐6 release. In addition, stevioside and steviol showed immunomodulatory effects on IκBα activation and nuclear factor kappa B ( NF‐κB ) suppression in western blotting . CONCLUSION Stevioside and steviol attenuate LPS ‐induced pro‐inflammatory cytokine productions by affecting cytokine gene expression via IκBα / NF‐κB signalling pathway. © 2013 Society of Chemical Industry