The prebiotics 2′-fucosyllactose prevent high-fat diet induced obesity via the promotion of thermogenesis and modulation of gut microbiota

2 '-fucosyllactose (2 '-FL) is one of the most prevalent milk oligosaccharides. In this study, the anti-obesity effect of 2 '-FL was explored in high-fat diet (HFD)-fed mice. Results showed that 2 '-FL alleviated body weight gain, improved serum lipid profiles and increased energy expenditure. Under cold exposure, 2 '-FL group showed higher body and rectal temperature, improving adaptive thermogenesis. 2 '-FL alleviated lipid accumulation, increased mitochondrial DNA content, as well as upregulated the protein expression of thermogenic markers including UCP1, PRDM16, PGC-1 alpha and the phosphorylation of AMPK in both white and brown adipose tissue. 2 ' FL also increased the diversity of gut microbiota in HFD mice. The Bacteroides/Firmicutes ratio, and the Bifidobacterium abundance were increased, while Lachnospiraceae abundance was decreased after 2 '-FL treatment. Moreover, 2 '-FL to HFD mice altered the bile acid profiles at levels comparable to normal diet group. These results indicates that 2 '-FL promotes thermogenesis and modulates gut microbiota to alleviate obesity.