Theabrownin from Fu Brick Tea Ameliorates Obesity via Modulating Tryptophan Metabolism and Downregulating Intestinal Lipid Transporters.

This study aims to explore the underlying mechanism by which theabrownin extracted from Fu brick tea (FBTB) alleviates obesity induced by a high-fat diet (HFD) in mice. Results showed that FBTB intervention ameliorated metabolic disorders, suppressed jejunal lipid accumulation, and enhanced fecal lipid excretion. 16S rRNA gene sequencing demonstrated that FBTB reversed gut microbiota dysbiosis and increased the abundance of potentially beneficial genera such as Dubosiella and Lactobacillus. Metabolomics revealed that FBTB altered tryptophan metabolism and significantly increased cecal levels of indole-3-acetic acid (IAA) and indole-3-propionic acid (IPA). Furthermore, these metabolites activated jejunal aryl hydrocarbon receptor (AhR) and interleukin-22 (IL-22) signaling, subsequently downregulating lipid transporters FATP4 and CD36 to reduce jejunal lipid accumulation. Notably, antibiotic treatment significantly blunted the suppressive effect of FBTB on jejunal lipid accumulation. Overall, FBTB prevents obesity may be through modulating the gut microbiota-tryptophan-IL-22 axis to reduce intestinal lipid accumulation.