Green tea extract and black tea extract differentially influence cecal levels of short-chain fatty acids in rats.

Tomonori Unno,Naomi Osakabe

doi:10.1002/fsn3.607

Abstract

Increasing evidence indicates that gut microbiota plays a critical role to maintain the host's health. The biological function of microbially produced short‐chain fatty acids (SCFA) becomes the focus of attention. This study aimed to compare the effects of green tea extract (GTE) and black tea extract (BTE) on cecal levels of SCFA in rats. Rats consumed an assigned diet of either a control diet, a GTE diet (10 g/kg), or a BTE diet (10 g/kg), for 3 weeks. The dietary addition of GTE significantly reduced the concentrations of acetate and butyrate in cecal digesta compared to the control, but BTE showed an increased trend for a cecal pool. In the GTE group, a significant amount of undigested starch was excreted in feces, but BTE produced no effect. Interestingly, feces of rats fed the BTE diet contained higher bacterial 16S rRNA gene copy numbers for total eubacteria compared to the control diet. Taken together, treatments of the diets with GTE and BTE brought about a different degree of producing SCFA in rat cecum. BTE might advantageously stimulate more SCFA production than GTE by facilitating bacterial utilization of starch.

Highlights

More than 100 trillion bacteria live symbiotically with our intestine, building the collective community
short-chain fatty acids (SCFA) bind G protein-coupled receptors, namely GPR41 and GPR43, which are expressed in enteroendocrine cells in the intestinal epithelium, and activate the secretion of peptide YY (PYY) and glucagon-like peptide-1 (GLP-1), which are responsible for reducing food intake and increasing energy expenditure
Food intake was comparable among the groups, the addition of green tea extract (GTE) or black tea extract (BTE) to the diet brought about a common distinctive feature of increasing wet mass of cecal digesta compared to the control group

Summary

Introduction

More than 100 trillion bacteria live symbiotically with our intestine, building the collective community. Attention is currently focused on the intricate role of intestinal microbial ecosystems in maturating immune system and modulating energy metabolism (Cénit, Matzaraki, Tigchelaar, & Zhernakova, 2014). It is recognized that environmental factors such as mode of birth, infant feeding patterns, antibiotic usage, and long-term dietary habit influence the overall microbial community (Power, O’Toole, Stanton, Ross, & Fitzgerald, 2014). SCFA bind G protein-coupled receptors, namely GPR41 and GPR43, which are expressed in enteroendocrine cells in the intestinal epithelium, and activate the secretion of peptide YY (PYY) and glucagon-like peptide-1 (GLP-1), which are responsible for reducing food intake and increasing energy expenditure (den Besten et al, 2013).

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