Fig. 7: Total parenteral nutrition impairs hepatic metabolic zonation in neonatal pigs.

A Schematic representation of key aspects of orally-fed (MILK) and TPN-fed (TPN) piglets. Created with BioRender.com. B Representative pictures of immunohistochemistry against Glutamine synthetase in the liver of 2-week-old orally-fed and TPN-fed piglets. Zone 1 and Zone 3 are highlighted in each image. Scale bar 100 μm. C Representative pictures of immunofluorescence against Glutamine synthetase in the liver of 2-week-old orally-fed and TPN-fed piglets. Zone 1 and Zone 3 are highlighted in each image. Scale bar 100 μm. D, E RT-qPCR of livers from 2-week-old orally-fed (n = 6) and TPN-fed (n = 6) piglets. Expression levels of the indicated genes relative to the average level in control milk piglets. Atp5f1 was used as housekeeping gene. Statistical significance was calculated by using multiple unpaired two-tailed t-test. F PCA of the transcriptomic profiles of the samples. Each dot represents individual biological replicates. G GSEA in TPN-fed compared to orally-fed piglets on the list of significantly upregulated genes or downregulated genes in Li-TSC1^KORagA^GTP liver samples. NES normalized enrichment score, FDR false discovery rate. H GSEA in TPN-fed compared to orally-fed piglets on the list of significantly upregulated or downregulated genes related with zonation in Li-TSC1^KORagA^GTP liver samples. NES normalized enrichment score; FDR false discovery rate. I Enrichment plot for the “Wnt/β-catenin related genes” signature for TPN-fed versus control livers from piglets at the mRNA level. NES normalized enrichment score, FDR false discovery rate. J RT-qPCR of livers from 2-week-old orally-fed (n = 6) and TPN-fed (n = 6) piglets. Expression levels of Wnt2 relative to the average level in control milk piglets. Atp5f1 was used as housekeeping gene. Statistical significance was calculated by using unpaired two-tailed t-test. K Nutrient and hormone signaling to mTORC1 as a metabolic trigger of hepatic zonation. Created with BioRender.com. In all panels data are presented as mean values ± standard deviation.