Adipokines influence on suckling rat GALT and microbiota

Dietary components in early life play a role in both microbiota and intestinal immune systemmaturation in mammalian species. Adipokines, as endogenously produced hormones from breastmilk, may have an impact on this process. The aim of the present study was to establish the influenceof leptin and adiponectin supplementation during suckling on the intraepithelial lymphocytecomposition, intestinal gene expression and gut microbiota in rat. For this purpose, newborn Wistarrats were supplemented daily with leptin, adiponectin or whey protein concentrate during the first 21days of life. Lymphocyte composition was established by immunofluorescence staining and flowcytometry analysis; intestinal gene expression by real-time PCR and cecal microbiota were analyzedthrough 16S rRNA gene sequencing. Although leptin and adiponectin were able to increase the TcTCRαβ + , CD8 + and NKT cell proportion, they decreased the NK cell percentage in IEL. Furthermore,both adipokines enhanced the gene expression of TNF-α, MUC-2 and MUC-3, and decreased that ofFcRn. In addition, the adipokine supplementations decreased the abundance of the Proteobacteriaphylum and the presence of Blautia. Moreover, leptin-supplemented animals had lower relativeabundance of Sutterella and a higher proportion of Clostridium genus, among others. However,supplementation with adiponectin resulted in lower abundance of the Roseburia genus and a higherproportion of the Enterococcus genus. In conclusion, the supplementation with leptin and adiponectinthroughout the suckling period had an impact on both the IEL composition and the gut microbiotapattern, suggesting a modulatory role of these adipokines on the development of intestinalfunctionality.