The Effect of 2′-Fucosyllactose on Gut Health in Aged Mice

This study aimed to explore the effect of 2'-Fucosyllactose (2'-FL) on the gut health of aged mice. The results revealed that 2'-FL intervention effectively improved the intestinal permeability and reduced the serum diamine oxidase (DAO) level in aged mice (<i>p</i> < 0.05); in addition, 2'-FL increased the IgA level and decreased the IgG level (<i>p</i> < 0.05). Meanwhile, 2'-FL reduced the serum levels of IL-6, IL-1β, TNF-α, and IFN-γ (<i>p</i> < 0.05). Histopathological analysis indicated that 2'-FL successfully reversed intestinal damage in the jejunum and colon. Additionally, 2'-FL increased the expression of the tight-junction proteins ZO-1 and Claudin-1 both at mRNA and protein levels (<i>p</i> < 0.05), and also down-regulated the expression of pro-inflammatory factors (IL-6, IL-1β) (<i>p</i> < 0.05), and decreased aging-related markers P16^INK4α and P21^Cip1. Furthermore, 16S rRNA results showed that 2'-FL increased the relative abundance of beneficial bacteria in the gut, such as <i>Lachnospiraceae</i>_UCG-006, norank_f__<i>Muribaculaceae</i> and <i>Lachnospiraceae_</i>NK4A136_group. In conclusion, 2'-FL effectively improved the intestinal immune health of the aged mice and provided a theoretical basis for its application as a functional component in the treatment of intestinal diseases.