The adverse and beneficial effects of polyphenols in green and black teas <i>in vitro</i> and <i>in vivo</i>
Mei-Hui Wu, Jer-Yuh Liu, Fang Ling Tsai, Jyuan-Jen Syu, Ciao-Sin Yun, Liang-Ying Chen, Je‐Chiuan Ye
Abstract
, we examined the impact of two green (G3 & G7) and two black (R3 & R8) teas with varying polyphenol content on dextran sulfate sodium (DSS)-induced inflammatory colitis in mice. Tea-treated groups exhibited significantly lower inflammatory scores (DAI) than the control group. DSS treatment in the control group led to shortened colorectal lengths in mice, while tea co-treatment partially prevented this loss. Histological analysis revealed that G7 and R3 (with a moderate polyphenol content) treatment improved colorectal crypt structure, decreased the severity of inflammatory ulcerative colitis, and significantly reduced histological scores compared to the control group. However, G3 and R8 (with high and low doses of polyphenol content, respectively) did not show these effects, suggesting that a moderate polyphenol level in both tea types is optimal for preventative benefits.