Macrophage phenotype could change by administration of EGCG in colitis mice
In our previous study, the macrophage phenotype could be changed with EGCG treat17. To further understand the potential mechanism by which EGCG therapy mitigate intestinal inflammation in this study, we analyzed the macrophages accumulation and the polarization of M1 macrophage by IHC and western blot analyses. The results showed that the levels of F4/80, which is marker of macrophages, were increased by DSS treat compare with normal group. And EGCG treatment could attenuate the macrophages accumulated (figure 4A). More importantly, the nitric oxide synthase (iNOS, M1 specific mark) were down-regulated with EGCG treat (figure 4A). The protein of iNOS expression was also decreased by EGCG treatment compared with mice in the DSS group (figure 4B and 4C). These results show that EGCG resolve inflammation of the colons partly because of reduced macrophages, especially the type of M1 macrophages.