Project description:Emerging knowledge shows the importance of early life events in programming the intestinal mucosal immune system and development of the intestinal barrier function. These processes depend heavily on close interactions between gut microbiota and host cells in the intestinal mucosa. In turn, development of the intestinal microbiota is largely dependent on available nutrients and substrates required for the specific microbial community structures to expand. It is currently not known what the specificities are of intestinal microbial community structures in relation to the programming of the intestinal mucosal immune system and development of the intestinal barrier function. The objective of the present study was to investigate the effect of a nutritional intervention on intestinal development of suckling piglets by daily oral administration of fructooligosaccharides (FOS) over a period of 12 days. At the microbiota community level a clear “bifidogenic” effect of the FOS administration was observed in colon digesta at day 14. The former, however, did not translate into significant changes of local gene expression in the colonic mucosa. In the jejunum, significant changes were observed for microbiota composition at day 14, and microbiota diversity at day 25. In addition, significant differentially expressed gene sets in mucosal tissues of jejunum were identified at both days 14 and 25 of age. At the age of 14 days, lower activity of cell cycle-related processes and a higher activity of extracellular matrix processes were observed in jejunal scrapings of piglets supplemented with FOS compared to control piglets. At day 25, lower activity of immune-related processes in jejunal tissue were seen in piglets supplemented with FOS. Histological parameters, villi height and crypt depth, were significantly different at day 25 between the experimental and control group, where piglets supplemented with FOS had higher villi and deeper crypts. We conclude that oral FOS administration during the suckling period of piglets has significant bifidogenic effects on the microbiota in the colon and on gene expression in jejunal mucosa scrapings. We hypothesize that FOS supplementation of suckling piglets results in a higher butyrate production in the colon due to the increase in bifidobacteria and lactobacilli in the hindgut. We further speculate that a higher butyrate production in colonic digesta relates to changes in gene expression in the jejunum by thus far unknown mechanisms.
Project description:Weaning is a very critical period for piglets, typically accompanied by lower feed intake, weight loss after weaning and increased mortality. At weaning, piglets are exposed to many stressors, such as loss of mothering, mixing with other litters, end of lactational immunity, and a change in their environment and gut microbiota. After weaning, morphological and histological changes occur in the small intestine of piglets producing a rapid change of feeding regime which is critical for the immature digestive system. Sixteen female piglets were weaned to assess the effect of sorbic acid supplementation on the small intestine tissue transcriptome. At weaning day (T0), 4 piglets were sacrified and tissue samples collected. The remaining 12 piglets were weighted and randomly assigned to different post weaning (T5) diets. Diet A (n=6) contained 5 g/kg of sorbic acid. Diet B (n=6) is the same as Standard diet. Total RNA was isolated from ileum samples to be analyzed using the a CombiMatrix CustomArrayTM 90K platform . Even though diet had no detectable effect during the first 5 days after weaning, outcomes from this study highlighted some of the response mechanisms to the stress of weaning occurring in the piglet gut. A total of 205 differentially expressed genes were used for functional analysis using bioinformatics through BLAST2GO, Ingenuity Pathway Analysis 8.0, and the Dynamic Impact Aproach (DIA). Bioinformatics analysis revealed that Apoptosis, RIG-I-like and NOD-like receptor signaling were altered as a result of weaning. Results suggest that immune and inflammatory responses were activated and likely are a cause of small intestine atrophy as revealed by a decrease in villus height and villus/crypt ratio. Keywords: weaning, gut, gene expression, sorbic acid, microarray analysis
Project description:In this study, we applied the isobaric tags for relative and absolute quantitation (iTRAQ) technique to detect alterations in the proteomic profile of the jejunal mucosa using a porcine model in which piglets were offered the protein-limited (PL) diet. Protein identification and quantification for iTRAQ experiments were performed using ProteinPilot (v4.0.8085) software. The LC-MS/MS data were searched against the UniProtKB (sus scrofa). To minimize the false discovery rate (FDR), a threshold for protein identification was applied, with the confident value > 95% (amount to the confident value “unused ProtScore” > 1.3 in ProteinPilot software), and at least one unique peptide was considered for protein identification. Proteins that were quantified with fold change > 2.0 were considered to be differentially expressed proteins. We identified 5275 proteins, 202 of which were differentially expressed. Furthermore, we adopted function annotation analysis of all identified proteins and function enrichment analysis of all differentially expressed proteins to explore more meaningful proteins and pathways.