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:Micronutrient deficiencies and environmental exposures have been to known to adversely impact brain and nervous system functions in adults and children worldwide. However, few studies have examined the short and long-term impact of these risk factors on neurodevelopmental outcomes in children in low-income countries, where the effects are likely to be more pronounced due to limited resources for monitoring and insufficient regulations. Biological risk factors of relevance include micronutrient deficiencies such as zinc and exposure to heavy metals such as lead and mercury. Studies have suggested an association between neurodevelopmental impairment and micronutrient deficiency as well as exposure to a number of heavy metals and environmental toxins. Moreover, findings also suggest that risk factors for adverse developmental outcomes that are independently significant may have the potential for causing cumulative increases in adverse effects. In Sub-Saharan Africa, severe malaria is a leading risk factor for long-term neurocognitive impairment in children. Zinc deficiency or exposure to heavy metals could influence risk of severe malaria, modify the risk of neurocognitive impairment in children with severe malaria, or independently affect risk of neurocognitive impairment. Untargeted analyses for potential environmental exposures or metabolomic changes in children with cerebral malaria vs. without cognitive impairment or in children with higher vs. lower cognitive scores, could also identify new risk factors for neurodevelopmental impairment in Ugandan children with cerebral malaria.In our completed study in Kampala, we assessed neurologic and developmental impairment in children with cerebral malaria [CM] or severe malarial anemia [SMA], as compared to health community children from the same extended household as the children with CM or SMA. As an extension of this study, we are interested in determining levels of micronutrients such as zinc in the population, and in addition, determining exposure levels of heavy metals (lead, mercury, copper, manganese etc.) in samples collected from children with severe malaria and community controls. The primary hypotheses of this study is that nutrient deficiencies or exposure to heavy metals influence short and long term neurocognitive outcomes in healthy community children and in children with severe malaria, and that children with cerebral malaria have specific metabolomic changes that relate to long-term neurocognitive impairment. The specific aims of our study are:Aim 1: To determine levels of zinc, heavy metals, and biomarkers associated with inflammation in children presenting with different forms of severe malaria (SM) and in healthy community children (CC). The working hypothesis of this aim is that 1) children with SM will have lower zinc levels compared to CC; 2) children with SM will present with higher toxic metal exposure and higher levels of biomarkers associated with inflammation than CC.Aim 2: To investigate how micronutrient deficiency, toxic metal exposure and inflammatory biomarkers affect short and long term neurodevelopmental outcomes and growth in children with severe malaria and community children (CC).The working hypothesis of this aim is that the lower levels of zinc, and presence of toxic metals in high concentrations will independently contribute to worsening neurodevelopmental outcomes and worsening growth over time in children with severe malaria and in community children. An alternate hypothesis is that micronutrient deficiency, toxic metal exposure and inflammatory states may interact with each other and with severe malaria to produce greater neurodevelopmental impairment, i.e., that the contribution is not independent but interactive.Aim 3: To determine whether the CSF metabolome differs according to level of neurodevelopmental impairment in children with cerebral malaria. The working hypothesis of this aim is that neurodevelopmental impairment in children with cerebral malaria is associated with changes in the CSF metabolome.
Project description:Microarray analysis of HT-29 cells co-cultured with tumor necrosis factor (TNF-a) in the presence or absence of polymeric formula as used for Exclusive Enteral Nutrition (EEN) therapy. Results provide insights into the molecular mechanisms underlying the anti-inflammatory effect of polymeric formula on intestinal epithelium.
Project description:The current study was designed to determine if dietary fatty acid concentration and composition affects the development and progression of nonalcoholic fatty liver disease. Male SD rats were overfed diets low (5%) or high (70%) fat diets via total enteral nutrition where the fat source was olive oil (monounsaturated), or corn oil (polyunsaturated). Overfeeding 5% corn oil produced little steatosis relative to feeding 5% olive oil. This was associated with lower fatty acid synthesis and reduced SREBP-c signaling in the 5% corn oil group. Overfeeding 70% fat diets increased steatosis and lead to increased liver necrosis in the 70% corn oil but not olive oil group. Increased injury after feeding polyunsaturated fat diets was linked to peroxidizability of hepatic free fatty acids and triglycerides and appearance of peroxidaized lipid products HETES and HODES previously linked to clinical nonalcoholic steatohepatitis. Male SD rats were overfed diets low (5%) or high (70%) fat diets via total enteral nutrition where the fat source was olive oil (monounsaturated) or corn oil (polyunsaturated).
Project description:Children with Hirschsprung disease (HD) who have a history of enterocolitis (HAEC) have a shift in colonic microbiota, many of which are necessary for short chain fatty acid (SCFA) production. As SCFAs play a critical role in colonic mucosal preservation, we hypothesized that fecal SCFA composition is altered in children with HAEC. Patients between age of 6 weeks and 16 years of age who were undergoing small bowel resection were selected, including those who were either receiving enteral nutrition preoperatively (control group), or those who were without enteral nutrition and receiving total parenteral nutrition (TPN group). At the time of operation, 100-500µl of effluent from the small bowel lumen was aspirated during the small bowel resection. The samples were immediately frozen in liquid nitrogen and stored at -80oC.
Research is published:
http://www.sciencedirect.com/science/article/pii/S0022346815006211
Project description:Opioid analgesics are frequently prescribed in the United States and worldwide. However, serious side effects such as addiction, immunosuppression and gastrointestinal symptoms limit long term use. In the current study using a chronic morphine-murine model a longitudinal approach was undertaken to investigate the role of morphine modulation of gut microbiome as a mechanism contributing to the negative consequences associated with opioids use. The results revealed a significant shift in the gut microbiome and metabolome within 24 hours following morphine treatment when compared to placebo. Morphine induced gut microbial dysbiosis exhibited distinct characteristic signatures profiles including significant increase in communities associated with pathogenic function, decrease in communities associated with stress tolerance. Collectively, these results reveal opioids-induced distinct alteration of gut microbiome, may contribute to opioids-induced pathogenesis. Therapeutics directed at these targets may prolong the efficacy long term opioid use with fewer side effects.
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: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.