EGCG reduced the level of inflammatory cytokines in colon tissues of DSS-treated mice
The increased inflammation cytokines, such as TNF-α, IL-1β, IL-6, MCP-1, plays a critical role in DSS-induced ulcerative colitis4. To investigate the effect of EGCG on inflammation-associated molecules, ELISA assay was performed to confirm the effects of EGCG on the protein levels of TNF-α, IL-1β, IL-6 and MCP-1. Compared with the Normal group, these cytokines in colonic tissue were upregulated markedly in colonic tissues of mice with oral administration of DSS (figure3A, 3B, 3C and 3D). While secretion levels of these inflammatory cytokines were significantly suppressed in mice treated with EGCG (figure3A, 3B, 3C and 3D). Furthermore, we evaluated the expression levels of TNF-α and IL-1β using western blot assays. The levels of TNF-α and IL-1β was significantly reduced by EGCG treat compare with those of the DSS treatment group (figure 3E, 3F and 3G). Taken together, these data indicated that EGCG could inhibit the overwhelming inflammatory response in colonic tissue of mice with DSS-induced colitis.