Michael Ladegaard Jensen

Similar efficacy of human banked milk and bovine colostrum to decrease incidence of necrotizing enterocolitis in preterm piglets

Preterm birth and formula feeding predispose to necrotizing enterocolitis (NEC) in infants. As mothers milk is often absent following preterm delivery, infant formula (IF) and human donor milk (HM) are frequently used as alternatives. We have previously shown that porcine and bovine colostrum (BC) provide similar NEC protection in preterm piglets relative to IF. We hypothesized that HM exerts similar effects and that this effect is partly species-independent. Preterm piglets (n = 40) received 2 days of total parenteral nutrition, followed by a rapid transition to full enteral feeding (15 ml·kg(-1)·2 h(-1)) for 2 days using BC (n = 13), HM (n = 13), or IF (n = 14). Intestinal passage time and hexose absorption were tested in vivo. Body and organ weights were recorded on day 5, and macroscopic NEC lesions in the gastrointestinal tract were assessed. Intestinal samples were collected for determination of histomorphology, histopathology, tissue IL-6 and IL-8, organic acids, bacterial adherence by fluorescence in situ hybridization score, and digestive enzyme activities. Relative to IF, pigs from BC and HM showed longer intestinal passage time; higher weight gain, hexose absorptive capacity, mucosal proportion, and enzyme activities; lower NEC incidence, organic acid concentration, and IL-8 concentration; and reduced histopathology lesions. Tissue IL-6 concentration and bacterial adherence score were lower for HM, relative to both BC and IF groups. We conclude that BC and HM are both superior to IF in stimulating gut structure, function, and NEC resistance in preterm piglets. BC may be a relevant alternative to HM when mothers milk is unavailable during the first week after preterm birth.

Antibiotics modulate intestinal immunity and prevent necrotizing enterocolitis in preterm neonatal piglets

Preterm birth, bacterial colonization, and formula feeding predispose to necrotizing enterocolitis (NEC). Antibiotics are commonly administered to prevent sepsis in preterm infants, but it is not known whether this affects intestinal immunity and NEC resistance. We hypothesized that broad-spectrum antibiotic treatment improves NEC resistance and intestinal structure, function, and immunity in neonates. Caesarean-delivered preterm pigs were fed 3 days of parenteral nutrition followed by 2 days of enteral formula. Immediately after birth, they were assigned to receive either antibiotics (oral and parenteral doses of gentamycin, ampicillin, and metronidazole, ANTI, n = 11) or saline in the control group (CON, n = 13), given twice daily. NEC lesions and intestinal structure, function, microbiology, and immunity markers were recorded. None of the ANTI but 85% of the CON pigs developed NEC lesions by day 5 (0/11 vs. 11/13, P < 0.05). ANTI pigs had higher intestinal villi (+60%), digestive enzyme activities (+53-73%), and goblet cell densities (+110%) and lower myeloperoxidase (-51%) and colonic microbial density (10(5) vs. 10(10) colony-forming units, all P < 0.05). Microarray transcriptomics showed strong downregulation of genes related to inflammation and innate immune response to microbiota and marked upregulation of genes related to amino acid metabolism, in particular threonine, glucose transport systems, and cell cycle in 5-day-old ANTI pigs. In a follow-up experiment, 5 days of antibiotics prevented NEC at least until day 10. Neonatal prophylactic antibiotics effectively reduced gut bacterial load, prevented NEC, intestinal atrophy, dysfunction, and inflammation and enhanced expression of genes related to gut metabolism and immunity in preterm pigs.

Modulation of Intestinal Inflammation by Minimal Enteral Nutrition With Amniotic Fluid in Preterm Pigs

BACKGROUND Necrotizing enterocolitis (NEC) is a severe inflammatory disorder, associated with the difficult transition from parenteral to enteral feeding after preterm birth. We hypothesized that minimal enteral nutrition (MEN) with amniotic fluid (AF), prior to enteral formula feeding, would improve resistance to NEC in preterm pigs. METHODS Experiment 1: IEC-6 cells were incubated with porcine (pAF) and human AF (hAF) to test AF-stimulated enterocyte proliferation and migration in vitro. Experiment 2: Cesarean-delivered, preterm pigs were fed parenteral nutrition and MEN with pAF, hAF, or control fluid (MEN-pAF, MEN-hAF, or MEN-CTRL; all n = 9) for 2 days before tissue collection. Experiment 3: Preterm pigs were fed MEN diets as in experiment 2, but followed by 2 days of enteral formula feeding, which predisposes to NEC (NEC-pAF, NEC-hAF, or NEC-CTRL; n = 10-12). RESULTS Both pAF and hAF stimulated enterocyte proliferation and migration in vitro. In experiment 2, MEN-pAF and MEN-hAF pigs showed increased body weight gain and reduced intestinal interleukin (IL)-8 and colonic IL-6 levels, indicating reduced inflammatory response. In experiment 3, body weight gain was highest in the 2 groups fed AF as MEN, but NEC incidences were similar (NEC-pAF) or increased (NEC-hAF) compared with controls. CONCLUSIONS Intake of pAF or hAF improved body growth and modulated intestinal inflammatory cytokines during a period of parenteral nutrition, but did not protect against later formula-induced NEC in preterm pigs. Further studies are required to show if MEN feeding with species-specific AF, combined with an optimal enteral diet (eg, human milk), will improve adaptation during the transition from parenteral to enteral feeding in preterm neonates.

Antibiotics Increase Gut Metabolism and Antioxidant Proteins and Decrease Acute Phase Response and Necrotizing Enterocolitis in Preterm Neonates

Background The appropriate use of antibiotics for preterm infants, which are highly susceptible to develop necrotizing enterocolitis (NEC), is not clear. While antibiotic therapy is commonly used in neonates with NEC symptoms and sepsis, it remains unknown how antibiotics may affect the intestine and NEC sensitivity. We hypothesized that broad-spectrum antibiotics, given immediately after preterm birth, would reduce NEC sensitivity and support intestinal protective mechanisms. Methodology/Principal Findings Preterm pigs were treated with antibiotics for 5 d (oral and systemic doses of gentamycin, ampicillin and metrodinazole; AB group) and compared with untreated pigs. Only the untreated pigs showed evidence of NEC lesions and reduced digestive function, as indicated by lowered villus height and activity of brush border enzymes. In addition, 53 intestinal and 22 plasma proteins differed in expression between AB and untreated pigs. AB treatment increased the abundance of intestinal proteins related to carbohydrate and protein metabolism, actin filaments, iron homeostasis and antioxidants. Further, heat shock proteins and the complement system were affected suggesting that all these proteins were involved in the colonization-dependent early onset of NEC. In plasma, acute phase proteins (haptoglobin, complement proteins) decreased, while albumin, cleaved C3, ficolin and transferrin increased. Conclusions/Significance Depressed bacterial colonization following AB treatment increases mucosal integrity and reduces bacteria-associated inflammatory responses in preterm neonates. The plasma proteins C3, ficolin, and transferrin are potential biomarkers of the colonization-dependent NEC progression in preterm neonates.

α1,2-fucosyllactose Does Not Improve Intestinal Function or Prevent Escherichia coli F18 Diarrhea in Newborn Pigs

Objectives: Infectious diarrhea, a leading cause of morbidity and deaths, is less prevalent in breastfed infants compared with infants fed infant formula. The dominant human milk oligosaccharide (HMO), &agr;-1,2-fucosyllactose (2′-FL), has structural homology to bacterial adhesion sites in the intestine and may in part explain the protective effects of human milk. We hypothesized that 2′-FL prevents diarrhea via competitive inhibition of pathogen adhesion in a pig model for sensitive newborn infants. Methods: Intestinal cell studies were coupled with studies on cesarean-delivered newborn pigs (n = 24) without (control) or with inoculation of enterotoxigenic Escherichia coli F18 (7.5 × 1010/day for 8 days) fed either no (F18) or 10 g/L 2′-FL (2FL-F18). Results: In vitro studies revealed decreased pathogen adhesion to intestinal epithelial cells with 2′-FL (5 g/L; P < 0.001). F18 pigs showed more diarrhea than control pigs (P < 0.01). Administration of 2′-FL to F18 pigs failed to prevent diarrhea, although the relative weight loss tended to be reduced (−19 vs −124 g/kg, P = 0.12), higher villi were observed in the distal small intestine (P < 0.05), and a trend toward increased proportion of mucosa and activities of some brush border enzymes in the proximal small intestine. In situ abundance of &agr;-1,2-fucose and E coli was similar between groups, whereas sequencing showed higher abundance of Enterobacteriaceae in F18, Enterococcus in control and Lachnospiraceae in 2FL-F18 pigs. Conclusions: 2′-FL inhibited in vitro adhesion of E coli F18 to epithelial cells, but had limited effects on diarrhea and mucosal health in newborn pigs challenged with E coli F18.

Escherichia coli challenge in newborn pigs.

Escherichia coli F18 is a common porcine enteric pathogen causing diarrhea and edema in weaned pigs. An essential step in the pathogenesis of this enteric colibacillosis is a fimbria-receptor interaction in the small intestine, involving the α(1,2)-fucosyltransferase gene (FUT1) enzyme for bacterial receptor binding to the epithelium. Enzyme expression is genetically determined and increases after weaning at 3 to5 wk, probably due to age- and/or diet-related intestinal maturation. We hypothesized that artificially reared piglets, deprived of sows milk from birth, show susceptibility to F18 already in the neonatal period. First we verified the intestinal expression of FUT1 in preterm, term, and weaned pigs by quantitative real-time polymerase chain reaction. Then age-related F18 susceptibility (degree of diarrhea) was evaluated in 3-, 10-, and 20-d-old pigs after inoculation of 10(10) cfu E. coli F18 per day for 12 d. Finally, F18 susceptibility was evaluated in caesarean-delivered 0- to 7-d-old piglets inoculated daily with F18 as above. For all pigs, their sows were genotyped to ensure expression of the FUT1 enzyme. FUT1 expression was detected in the proximal and distal small intestine with no apparent differences in levels among preterm, term, and weaned pigs. No consistent F18-induced diarrhea was detected in any of the 3 groups of 3- to 20-d-old pigs. In contrast, 0- to 7-d-old caesarean-delivered pigs showed a higher score of diarrhea in pigs inoculated with F18 compared with controls (2.4 ± 0.1 vs. 1.8 ± 0.1 respectively; P < 0.001). Caesarean-delivered piglets deprived of sow milk are highly susceptible to diarrhea induced by E. coli F18. Lack of the protective effects of birth colonization and sow milk may contribute to high intestinal F18 sensitivity. The newborn pig may be a useful model to investigate factors in maternal milk that protect against F18 diarrhea.

Escherichia coli pchallenge in newborn igs1

Escherichia coli F18 is a common porcine enteric pathogen causing diarrhea and edema in weaned pigs. An essential step in the pathogenesis of this enteric colibacillosis is a fimbria-receptor interaction in the small intestine, involving the α(1,2)-fucosyltransferase gene (FUT1) enzyme for bacterial receptor binding to the epithelium. Enzyme expression is genetically determined and increases after weaning at 3 to5 wk, probably due to age- and/or diet-related intestinal maturation. We hypothesized that artificially reared piglets, deprived of sows milk from birth, show susceptibility to F18 already in the neonatal period. First we verified the intestinal expression of FUT1 in preterm, term, and weaned pigs by quantitative real-time polymerase chain reaction. Then age-related F18 susceptibility (degree of diarrhea) was evaluated in 3-, 10-, and 20-d-old pigs after inoculation of 10(10) cfu E. coli F18 per day for 12 d. Finally, F18 susceptibility was evaluated in caesarean-delivered 0- to 7-d-old piglets inoculated daily with F18 as above. For all pigs, their sows were genotyped to ensure expression of the FUT1 enzyme. FUT1 expression was detected in the proximal and distal small intestine with no apparent differences in levels among preterm, term, and weaned pigs. No consistent F18-induced diarrhea was detected in any of the 3 groups of 3- to 20-d-old pigs. In contrast, 0- to 7-d-old caesarean-delivered pigs showed a higher score of diarrhea in pigs inoculated with F18 compared with controls (2.4 ± 0.1 vs. 1.8 ± 0.1 respectively; P < 0.001). Caesarean-delivered piglets deprived of sow milk are highly susceptible to diarrhea induced by E. coli F18. Lack of the protective effects of birth colonization and sow milk may contribute to high intestinal F18 sensitivity. The newborn pig may be a useful model to investigate factors in maternal milk that protect against F18 diarrhea.

pchallenge in newborn igs

Escherichia coli F18 is a common porcine enteric pathogen causing diarrhea and edema in weaned pigs. An essential step in the pathogenesis of this enteric colibacillosis is a fimbria-receptor interaction in the small intestine, involving the α(1,2)-fucosyltransferase gene (FUT1) enzyme for bacterial receptor binding to the epithelium. Enzyme expression is genetically determined and increases after weaning at 3 to5 wk, probably due to age- and/or diet-related intestinal maturation. We hypothesized that artificially reared piglets, deprived of sows milk from birth, show susceptibility to F18 already in the neonatal period. First we verified the intestinal expression of FUT1 in preterm, term, and weaned pigs by quantitative real-time polymerase chain reaction. Then age-related F18 susceptibility (degree of diarrhea) was evaluated in 3-, 10-, and 20-d-old pigs after inoculation of 10(10) cfu E. coli F18 per day for 12 d. Finally, F18 susceptibility was evaluated in caesarean-delivered 0- to 7-d-old piglets inoculated daily with F18 as above. For all pigs, their sows were genotyped to ensure expression of the FUT1 enzyme. FUT1 expression was detected in the proximal and distal small intestine with no apparent differences in levels among preterm, term, and weaned pigs. No consistent F18-induced diarrhea was detected in any of the 3 groups of 3- to 20-d-old pigs. In contrast, 0- to 7-d-old caesarean-delivered pigs showed a higher score of diarrhea in pigs inoculated with F18 compared with controls (2.4 ± 0.1 vs. 1.8 ± 0.1 respectively; P < 0.001). Caesarean-delivered piglets deprived of sow milk are highly susceptible to diarrhea induced by E. coli F18. Lack of the protective effects of birth colonization and sow milk may contribute to high intestinal F18 sensitivity. The newborn pig may be a useful model to investigate factors in maternal milk that protect against F18 diarrhea.