Project description:Preterm neonates are susceptible to gastrointestinal (GI) disorders such as necrotizing enterocolitis (NEC). Maternal milk, and especially colostrum, protects against NEC via growth promoting, immunomodulatory and antimicrobial factors. The fetal enteral diet, amniotic fluid (AF), contains similar bioactive components and we hypothesized that postnatal AF administration would reduce inflammatory responses and NEC in preterm neonates. Thirty preterm pigs (92% gestation) were delivered by caesarean section and fed total parental nutrition (TPN) for 48 h followed by enteral porcine colostrum (COLOS, n=7), infant formula (FORM, n=13) or formula + porcine AF (AF, n=10). Using a previously validated model of NEC in preterm pigs, we determined the structural, functional, microbiological and immunological responses to AF when administered prior to and after introduction of a suboptimal enteral formula diet. Keywords: Healthy versus inflammed tissues in relation to necrotizing enterocolitis
Project description:The cardioprotective effects of long chain (LC) 3PUFA can be achieved at the gene expression level, notably in liver. However, the complexity of biological pathways modulations and the nature of the bioactive molecules are still under investigation. The present study aimed to investigate the dose-response effects of LC 3PUFA on the production of peroxidated metabolites and on global gene expression in liver. The intake of LC ?3PUFA increased, in a dose-dependent manner, their incorporation in liver phospholipids but also the hepatic production of 4-HHE. Pathways related to inflammation were dose-dependently associated with the 3 groups but Group 2 was rather associated with inflammatory effects while Group 3 was anti-inflammatory. LC ?3PUFA had no effect on PPAR-controlled genes. However, they modified, in a dose-dependent manner, the expression of major genes related to lipoprotein metabolism (LDLR, VLDLR, INSIG1 and MTTP), possibly through the FXR signaling pathway. In conclusion, the effect of LC ?3PUFA is dependent on the dose possibly because of the production of peroxidated metabolites such as 4-HHE. New-Zealand white rabbits were fed (7 wk) a high cholesterol diet and received by daily oral gavages either oleic acid rich oil or a mixture of oils providing 0.1% (Group 1), 0.5% (Group 2) or 1% (Group 3) of energy as docosahexaenoic acid. Specific peroxidated metabolite issued from LC 3PUFA (4-hydroxyhexenal or 4-HHE) were measured by GC/MS/MS and transcription profiling was conducted in liver. Differentially expressed genes were identified using Bioconductor (Moderated p<0.05, Fold Change>1.20) and clustered into pathways (Ingenuity Pathway Analysis 7.0).
Project description:Most commonly used models of non-alcoholic steatohepatitis (NASH) are diets based on specific gene knockouts or represent extreme manipulations of diet. We have examined the effects of modest increased caloric intake and high dietary unsaturated fat content on the development of NASH in male rats using a model in which overfeeding is accomplished via intragastric infusion of liquid diets as a part of total enteral nutrition. Male Sprague dawley rats were fed diets 5% corn oil containing diets at 187 Kcal/kg3/4/d or fed 70% corn oil containing diets at 220 Kcal/kg3/4/d for a period of 3 weeks. Hepatic gene expression were assessed at the end of the study. Our results indicate that overfeeding of high unsaturated fat diets leads to pathological, endocrine and metabolic changes characteristic of NASH patients and is associated with increased oxidative stress and TNF-a. Experiment Overall Design: Two groups of male sprague dawley rats were fed liquid diets via total enteral nutrition. Experiment Overall Design: Group 1, Control, Rats were fed diets containing 5% Corn oil at 187 Kcal/kg3/4/d for 3 weeks. Experiment Overall Design: Group 2, NASH, Rats were fed diets containing 70% corn oil at 220 Kcal/kg3/4/d for 3 weeks.
Project description:Caesarean-delivered preterm pigs were fed 3 d of parenteral nutrition followed by 2 d of enteral formula feeding. Antibiotics (n=11) or control saline (n=13) were given twice daily from birth to tissue collection at d 5. NEC-lesions and intestinal structure, function, microbiology and immunity markers were recorded. We used Affymetrix microarrays to investigate gene expression in intestinal tissues of preterm piglets treated with antibiotics or control saline. Twenty-four preterm piglets were delivered by caesarean section on day 105 of gestation from two healthy sows. All piglets were initially provided with parenteral nutrition via a vascular catheter, combined with small amounts of minimal enteral nutrition. On day three, all parenteral nutrition was stopped and total enteral nutrition was given through an oro-gastric feeding tube. Piglets were allocated into controls ( n=13) and an intervention group receiving oral and systemic broad-spectrum antibiotics ( n=11). To assure high systemic and intra luminal MIC values antibiotics were given both orally and intramuscularly. All antibiotics were given directly after feeding with an oral bolus and control pigs were given corresponding amounts of saline. On day five, all piglets were euthanized, and small intestinal tissue collected.
Project description:Preterm neonates are susceptible to gastrointestinal (GI) disorders such as necrotizing enterocolitis (NEC). Maternal milk, and especially colostrum, protects against NEC via growth promoting, immunomodulatory and antimicrobial factors. The fetal enteral diet, amniotic fluid (AF), contains similar bioactive components and we hypothesized that postnatal AF administration would reduce inflammatory responses and NEC in preterm neonates. Thirty preterm pigs (92% gestation) were delivered by caesarean section and fed total parental nutrition (TPN) for 48 h followed by enteral porcine colostrum (COLOS, n=7), infant formula (FORM, n=13) or formula + porcine AF (AF, n=10). Using a previously validated model of NEC in preterm pigs, we determined the structural, functional, microbiological and immunological responses to AF when administered prior to and after introduction of a suboptimal enteral formula diet. Keywords: Healthy versus inflammed tissues in relation to necrotizing enterocolitis Pigs from each treatment group (COLOS, n=4; FORM, n=6; and AF, n=7) were randomly selected for microarray analysis of frozen distal small intestine samples. The FORM group was further divided into formula-fed healthy pigs (F-HEA, n=3) and formula-fed NEC pigs (F-NEC, n=3) in order to compare sick versus healthy formula fed pigs. Equal amounts of total distal small intestinal RNA from all pigs were pooled to make the reference sample. Samples and reference pool were labelled with Oyster 550 and 650, respectively. The in-house spotted porcine oligonucleotide microarray version 4 (POM4) is a low density microarray consisting of 384 different oligonucleotide probes representing more than 200 different immune related genes.
Project description:The cardioprotective effects of long chain (LC) 3PUFA can be achieved at the gene expression level, notably in liver. However, the complexity of biological pathways modulations and the nature of the bioactive molecules are still under investigation. The present study aimed to investigate the dose-response effects of LC 3PUFA on the production of peroxidated metabolites and on global gene expression in liver. The intake of LC ω3PUFA increased, in a dose-dependent manner, their incorporation in liver phospholipids but also the hepatic production of 4-HHE. Pathways related to inflammation were dose-dependently associated with the 3 groups but Group 2 was rather associated with inflammatory effects while Group 3 was anti-inflammatory. LC ω3PUFA had no effect on PPAR-controlled genes. However, they modified, in a dose-dependent manner, the expression of major genes related to lipoprotein metabolism (LDLR, VLDLR, INSIG1 and MTTP), possibly through the FXR signaling pathway. In conclusion, the effect of LC ω3PUFA is dependent on the dose possibly because of the production of peroxidated metabolites such as 4-HHE.
Project description:Purpose: Surgical treatment of congenital and neonatal intestinal diseases often requires resection of intestine and/or diverstion of luminal flow. Subsequent growth on enteral nutrition alone depends on adaptation of the remaining bowel. The role of mechanoluminal stimulation in driving intestinal adaptation and the effects of depriving the intestine of mechanoluminal stimulation are unknown. Methods: 5 pairs of intestine from neonatal surgical patients were obtained at ileostomy reversal. The proximal segment contiguous with enteral feeding was denoted “fed” and the distal segment without luminal flow was denoted “unfed". Following RNA extraction, these samples underwent deep sequencing. Results: Fed intestine had increased expression of genes involved in inflammation and immune regulation and steroid secretion. Unfed intestine had increased expression of genes involved in digestion and transport. Conclusion: Independent of external influences, the presence or absence of enteral mechanoluminal stimulation causes significant alterations in gene expression in intestine.
Project description:Nutrition has a vital role in shaping the intestinal microbiome. The impact of nutrients and the consequences of enteral deprivation on the small intestinal mucosal microbiota, specifically in early life, has not been well described. Our aim was to study the impact of enteral deprivation on the small intestine mucosal microbiome and to search for factors that shape this interaction in early life. Host seem to be the most dominant factor in the structure of the early life mucosal microbial small intestine community. Under conditions of nutrient deprivation, there are specific changes in host proteomics. Further research is needed to better define and understand this host-microbe-nutrition interaction in the small intestine.
Project description:Excessive intake of dietary fat is known to be a contributing factor in the development of obesity. In this study, we determined the dose-dependent effects of dietary fat on the development of this metabolic condition with a focus on changes in gene expression in the small intestine. C57BL/6J mice were fed diets with either 10, 20, 30 or 45 energy% (E%) derived from fat for four weeks (n=10 mice/diet). We found a significant higher weight gain in mice fed the 30E% and 45E% fat diet compared to mice on the control diet. These data indicate that the main shift towards an obese phenotype lies between a 20E% and 30E% dietary fat intake. Analysis of differential gene expression in the small intestine showed a fat-dose dependent gradient in differentially expressed genes, with the highest numbers in mice fed the 45E% fat diet. The main shift in fat-induced differential gene expression was found between the 30E% and 45E% fat diet. Furthermore, approximately 70% of the differentially expressed genes were regulated in a fat-dose dependent manner. Many of these genes were involved in lipid metabolism-related processes and were already differentially expressed on a 30E% fat diet. Taken together, we conclude that up to 20E% of dietary fat, the small intestine has an effective ‘buffer capacity’ for fat handling. From 30E% of dietary fat, a switch towards an obese phenotype is triggered. We further speculate that especially fat-dose dependently regulated lipid metabolism-related genes are involved in development of obesity. The proximal, middle, and distal parts of the intestine of mice fed 10, 20, 30, or 45E% dietary fat were analyzed. 10 replicates each.