Aged Pu-Erh Tea Reduced Oxidative Stress-Mediated Inflammation in DSS-Induced Colitis Mice by Regulating Intestinal Microbes

Abstract

Background: Colitis is associated with gut microbiological disorders and oxidative stress-mediated intestinal inflammation. Pu-erh tea has been used as a beverage for bioactive potential in antioxidation and anti-inflammation. With increase of storage, the change of its bioactive components creates the difference of health care function. However, there is no evidence to show whether the storage period of Pu-erh tea affects its anti-inflammatory and anti-oxidant capacity in the colitis, or even intestinal protection. Results: In this study, 3.5% DSS-induced colitis mice were treated with 10 mg/kg bw/day extracts, aged 14 years (P2006) and unaged (P2020) Pu-erh tea respectively, for 1 week. It was found that Pu-erh tea, especially P2006, inhibited the intestinal oxidative stress-mediated inflammation signaling pathway (TLR4/MyD88/ROS/p38 MAPK/NF-κB p65), up-regulated the expression of intestinal tight junction proteins (Mucin-2, zonula occludens 1, occluding), promoted M2 polarization of macrophages, and in turn, improved the intestinal immune barrier, which stemmed from the reshaping of intestinal microbiota (e.g., increased Lachnospiraceae_NK4A136_group and Akkermansia levels). Conclusions: These results indicate that the changes of intestinal microflora caused by aged Pu-erh are the key to alleviate DSS-induced colitis, and speculate that drinking aged Pu-erh tea (10 mg/kg bw/day in mice, a human equivalent dose of 7 g/60 kg bw /day) has a practical effect on alleviating and preventing the development of intestinal inflammation.