Ellagic acid (EA) is a polyphenol found in fruits and vegetables that can be used as functional ingredient. Accumulating evidence suggests that the effects of EA have large interindividual variability, which is involved in the differences in gut microbiota. However, the mechanisms underlying such effects remain unclear. Here, we found that EA supplementation caused a significant reduction in the body weight of young mice other than adult mice. 16S rRNA gene sequencing revealed that EA significantly affected the abundance of Bacteroides in the young group and Akkermansia and Lactobacillus in the adult group. Short-chain fatty acids (SCFAs) exhibited that the propionic acid and butyric acid levels increased markedly in the young group but not in the adult group. EA activated the expression of peroxisome proliferator-activated receptor gamma (PPARγ), which plays a crucial role in body weight loss. Furthermore, transcriptome analysis showed that the regulated genes mainly correlated with the PPAR signaling pathway related to the endocrine system and lipid metabolism in the young group, whereas the adult group encompassed other various biological processes. The related genes were analyzed by real-time qualitative polymerase chain reaction (RT–qPCR), including the upregulated mRNA expression of Cd36 in the PPAR signaling pathway and Cyp2b9, Cyp7b1, Cyp1a2, Cyp4a32, and Elovl3 associated with lipid metabolism. Spearman’s correlation analysis indicated that the bacteria with significant changes in abundance were strongly correlated with the PPAR pathway and lipid metabolism-related genes. This work indicates that the benefits of EA on the gut environment are partly affected by the age of the host and deepens our understanding on how EA regulates the gut environment.

鞣花酸 (EA) 是一种存在于水果和蔬菜中的多酚，可用作功能性成分。越来越多的证据表明，电针的影响具有很大的个体差异，这与肠道微生物群的差异有关。然而，这种影响背后的机制仍不清楚。在这里，我们发现补充 EA 导致年轻小鼠体重显着降低，而不是成年小鼠。16S rRNA基因测序显示，EA显着影响年轻组拟杆菌属和Akkermansia和Lactobacillus的丰度在成人组。短链脂肪酸 (SCFAs) 表明，丙酸和丁酸水平在年轻组中显着增加，而在成人组中则没有。EA 激活了过氧化物酶体增殖物激活受体 γ (PPARγ) 的表达，这在体重减轻中起着至关重要的作用。此外，转录组分析表明，受调控的基因主要与年轻组内分泌系统和脂质代谢相关的PPAR信号通路相关，而成年组则包含其他各种生物过程。通过实时定性聚合酶链反应 (RT-qPCR) 分析相关基因，包括 PPAR 信号通路中 Cd36 和与脂质代谢相关的 Cyp2b9、Cyp7b1、Cyp1a2、Cyp4a32 和 Elovl3 的上调 mRNA 表达。Spearman相关分析表明，丰度发生显着变化的细菌与PPAR途径和脂质代谢相关基因密切相关。这项工作表明 EA 对肠道环境的益处部分受宿主年龄的影响，并加深了我们对 EA 如何调节肠道环境的理解。