The effect of dietary ginseng polysaccharide supplementation on porcine milk-derived esRNAs involved in the host immune responses.

Ginseng polysaccharides (GPS) have been well known as an immune modulator. This study was conducted to investigate the effects of dietary supplemental GPS on the immune responses involved in sow's milk-derived exosomal shuttle RNAs (esRNAs) using RNA-Seq and miRNA-Seq. Of the 213 identified miRNA types, a total of 26 conserved miRNAs were differently expressed in response to GPS supplementation, including 10 up-regulated and 16 down-regulated miRNAs in GPS feeding group. In addition, exosomal transcriptome analysis identified 14,696 protein-coding genes in sow's milk exosomes, and 283 genes with 204 and 79 candidates showing up and down-regulation were significantly responded to GPS supplementation. Integrated analysis of each differently expressed miRNA with significantly expressed genes further revealed the presence of 51 highly conserved miRNA-gene interactions that were annotated to be related to immunoregulatory functions. This work provided an important advance in the functional identification of dietary GPS supplementation and more fundamental information about how GPS promoted the immune response and healthy growth of the infant from mothers at molecular levels.