Alginate oligosaccharides improve hepatic metabolic disturbance via regulating the gut microbiota

Alginate oligosaccharides (AOS) derived from sodium alginate are novel prebiotics with multiple biological functions. Low birth weight (LBW) is a public health concern worldwide. However, the benefits of AOS in LBW mammals have not been determined. In this study, we found that AOS significantly improved the growth performance, colonic mucosal immunity, and jejunal nutrient digestion and transport of LBW piglets. Moreover, AOS alleviated liver injury by alleviating oxidative stress and pro-inflammatory responses, and improved hepatic lipid accumulation and insulin resistance by decreasing the levels of genes involved in lipid transport, de novo lipogenesis, and the insulin signaling. Integrated 16S rDNA, transcriptome, and metabolome analyses revealed that AOS alleviated the disruption of colonic mucosal immunity by increasing the abundance of Lactobacillus and short-chain fatty acids, and improved hepatic dysfunction via the tryptophan metabolites and aryl hydrocarbon receptor signaling. These findings revealed the effects and mechanisms of AOS in intestinal and hepatic dysfunction in LBW piglets, and broadened the potential application of AOS in improving postnatal maldevelopment in LBW infants.