Early Antibiotic Exposure Alters Intestinal Development and Increases Susceptibility to Necrotizing Enterocolitis: A Mechanistic Study.
Ontology highlight
ABSTRACT:
SUBMITTER: Chaaban H
PROVIDER: S-EPMC8951210 | biostudies-literature | 2022 Feb
REPOSITORIES: biostudies-literature
Publications
Early Antibiotic Exposure Alters Intestinal Development and Increases Susceptibility to Necrotizing Enterocolitis: A Mechanistic Study.
Chaaban Hala H Patel Maulin M MM Burge Kathryn K Eckert Jeffrey V JV Lupu Cristina C Keshari Ravi S RS Silasi Robert R Regmi Girija G Trammell MaJoi M Dyer David D McElroy Steven J SJ Lupu Florea F
Microorganisms 20220227 3
Increasing evidence suggests that prolonged antibiotic therapy in preterm infants is associated with increased mortality and morbidities, such as necrotizing enterocolitis (NEC), a devastating gastrointestinal pathology characterized by intestinal inflammation and necrosis. While a clinical correlation exists between antibiotic use and the development of NEC, the potential causality of antibiotics in NEC development has not yet been demonstrated. Here, we tested the effects of systemic standard- ...[more]
Similar Datasets
Project description:Enterohepatic helicobacter species (EHS) infect the intestinal tract and biliary tree, triggering intestinal and hepatic disorders. Helicobacter hepaticus, the prototypic murine EHS, is also associated with inflammation. Necrotizing enterocolitis (NEC) is a devastating disease of premature infants. The cause of NEC is not fully understood, but anomalies of bacterial colonization (dysbiosis) are thought to play an important role in disease onset. To evaluate the effect of H. hepaticus infection on the development of NEC, premature formula-fed rats were kept either in H. hepaticus-free conditions or colonized with H. hepaticus; both groups were exposed to asphyxia and cold stress. The incidence of NEC, expression of Toll-like receptors (TLRs), production of cytokines and mucins, and presence of autophagy regulators were evaluated at the site of injury. H. hepaticus infection increased the incidence of NEC from 39 to 71% and significantly increased levels of TLR4 receptor, expression of proinflammatory cytokines CXCL1, IL-1?, IL-12, and IL-23, and altered activation of autophagy. H. hepaticus induces inflammation and increases the incidence and severity of experimental NEC; this is consistent with observations in neonates of blooms of proinflammatory microbes just before the onset of NEC. Future studies using rodent NEC models should include testing for H. hepaticus infection. Further studies in neonates of early identification and/or diminution of proinflammatory microbes may be beneficial in decreasing the incidence of NEC.
| S-EPMC3798735 | biostudies-literature
Project description:Necrotizing enterocolitis (NEC) is a complication of prematurity. The etiology is unknown, but is related to enteral feeding, ischemia, infection, and inflammation. Reactive oxygen species production, most notably superoxide, increases in NEC. NADPH oxidase (NOX) generates superoxide, but its activity in NEC remains unknown. We hypothesize that NOX-derived superoxide production increases in NEC. Newborn Sprague-Dawley rats were divided into control, formula-fed, formula/LPS, formula/hypoxia, and NEC (formula, hypoxia, and LPS). Intestinal homogenates were analyzed for NADPH-dependent superoxide production. Changes in superoxide levels on days 0-4 were measured. Inhibitors for nitric oxide synthase (L-NAME) and NOX2 (GP91-ds-tat) were utilized. RT-PCR for eNOS, NOX1, GP91phox expression was performed. Immunofluorescence studies estimated the co-localization of p47phox and GP91phox in control and NEC animals on D1, D2, and D4. NEC pups generated more superoxide than controls on D4, while all other groups were unchanged. NADPH-dependent superoxide production was greater in NEC on days 0, 3, and 4. GP91-ds-tat decreased superoxide production in both groups, with greater inhibition in NEC. L-NAME did not alter superoxide production. Temporally, superoxide production varied minimally in controls. In NEC, superoxide generation was decreased on day 1, but increased on days 3-4. GP91phox expression was higher in NEC on days 2 and 4. NOX1 and eNOS expression were unchanged from controls. GP91phox and p47phox had minimal co-localization in all control samples and NEC samples on D1 and D2, but had increased co-localization on D4. In conclusion, this study proves that experimentally-induced NEC increases small intestinal NOX activity. All components of NEC model are necessary for increased NOX activity. NOX2 is the major source, especially as the disease progresses.
| S-EPMC4269454 | biostudies-literature
Project description:ObjectiveNecrotizing enterocolitis (NEC) is the most common surgical emergency in preterm infants, and pathogenesis associates with changes in the fecal microbiome. As fecal samples incompletely represent microbial communities in intestinal mucosa, we sought to determine the NEC tissue-specific microbiome and assess its contribution to pathogenesis.DesignWe amplified and sequenced the V1-V3 hypervariable region of the bacterial 16S rRNA gene extracted from intestinal tissue and corresponding fecal samples from 12 surgical patients with NEC and 14 surgical patients without NEC. Low quality and non-bacterial sequences were removed, and taxonomic assignment was made with the Ribosomal Database Project. Operational taxonomic units were clustered at 97%. We tested for differences between NEC and non-NEC samples in microbiome alpha- and beta-diversity and differential abundance of specific taxa between NEC and non-NEC samples. Additional analyses were performed to assess the contribution of other demographic and environmental confounding factors on the infant tissue and fecal microbiome.ResultsThe fecal and tissue microbial communities were different. NEC was associated with a distinct microbiome, which was characterized by low diversity, higher abundances of Staphylococcus and Clostridium_sensu_stricto, and lower abundances of Actinomyces and Corynebacterium. Infant age and vancomycin exposure correlated with shifts in the tissue microbiome.ConclusionThe observed low diversity in NEC tissues suggests that NEC is associated with a bacterial bloom and a distinct mucosal bacterial community. The exact bacterial species that constitute the bloom varied by infant and were strongly influenced by age and exposure to vancomycin.
| S-EPMC6203398 | biostudies-literature
Project description:Necrotizing enterocolitis (NEC) is the most devastating intestinal disease affecting preterm infants. In addition to being associated with short term mortality and morbidity, survivors are left with significant long term sequelae. The cost of caring for these infants is high. Epidemiologic evidence suggests that use of antibiotics and type of feeding may cause an intestinal dysbiosis important in the pathogenesis of NEC, but the contribution of specific infectious agents is poorly understood. Fecal samples from preterm infants ≤ 32 weeks gestation were analyzed using 16S rRNA based methods at 2, 1, and 0 weeks, prior to diagnosis of NEC in 18 NEC cases and 35 controls. Environmental factors such as antibiotic usage, feeding type (human milk versus formula) and location of neonatal intensive care unit (NICU) were also evaluated. Microbiota composition differed between the three neonatal units where we observed differences in antibiotic usage. In NEC cases we observed a higher proportion of Proteobacteria (61%) two weeks and of Actinobacteria (3%) 1 week before diagnosis of NEC compared to controls (19% and 0.4%, respectively) and lower numbers of Bifidobacteria counts and Bacteroidetes proportions in the weeks before NEC diagnosis. In the first fecal samples obtained during week one of life we detected a novel signature sequence, distinct from but matching closest to Klebsiella pneumoniae, that was strongly associated with NEC development later in life. Infants who develop NEC exhibit a different pattern of microbial colonization compared to controls. Antibiotic usage correlated with these differences and combined with type of feeding likely plays a critical role in the development of NEC.
| S-EPMC3875440 | biostudies-literature
Project description:BackgroundNecrotizing enterocolitis (NEC) is the most prevalent gastrointestinal disorder that predominantly threatens preterm newborns. Succinate is an emerging metabolic signaling molecule that was recently studied in relation to the regulation of intestinal immunity and homeostasis. We aimed to investigate the relationship between NEC and gut luminal succinate and preliminarily explored the effect of succinate on NEC pathogenesis.MethodsFecal samples from human neonates and mouse pups were analyzed by HPLC - MS/MS and 16S rRNA gene sequencing. C57BL/6 mice were randomly divided into four groups: control, NEC, Lsuc, and Hsuc. The mortality, weight gain, and intestinal pathological changes in four mouse groups were observed. Inflammatory cytokines and markers of macrophages were identified by quantitative real-time PCR. Succinate receptor 1 (SUCNR1) localization was visualized by immunohistochemistry. The protein levels of SUCNR1 and hypoxia-inducible factor 1a (HIF-1a) were quantified by western blotting.ResultsThe levels of succinate in feces from NEC patients were higher than those in feces from non-NEC patients (P <0.05). In the murine models, succinate levels in intestinal content samples were also higher in the NEC group than in the control group (P <0.05). The change in succinate level was closely related to intestinal flora composition. In samples from human neonates, relative to the control group, the NEC group showed a higher abundance of Enterobacteriaceae and a lower abundance of Lactobacillaceae and Lactobacillus (P <0.05). In the murine models, relative to the control group, increased abundance was observed for Clostridiaceae, Enterococcaceae, Clostridium_sensu_stricto_1, and Enterococcus, whereas decreased abundance was observed for Lactobacillaceae and Lactobacillus (P <0.05). Increased succinate levels prevented mice from gaining weight, damaged their intestines, and increased their mortality; upregulated the gene expression of interleukin-1β (IL-1β), IL-6, IL-18 and tumor necrosis factor (TNF); and downregulated the gene expression of IL-10 and transforming growth factor (TGF)-β. Exogenous succinic acid increased inducible nitric oxide synthase (iNOS) gene expression but decreased Arginase-1 (Arg1) gene expression; and increased the protein expression of SUCNR1 and HIF-1a.ConclusionSuccinate plays an important role in the development of necrotizing enterocolitis severity, and the activation of the HIF-1a signaling pathway may lead to disease progression.
| S-EPMC9742382 | biostudies-literature
Project description:Decreased intestinal perfusion may contribute to the development of necrotizing enterocolitis (NEC). Vascular endothelial growth factor (VEGF) is an angiogenic protein necessary for the development and maintenance of capillary networks. Whether VEGF is dysregulated in NEC remains unknown.The objective of this study was to determine whether intestinal VEGF expression is altered in a neonatal mouse model of NEC and in human NEC patients.We first assessed changes of intestinal VEGF mRNA and protein in a neonatal mouse NEC model before significant injury occurs. We then examined whether exposure to formula feeding, bacterial inoculation, cold stress and/or intermittent hypoxia affected intestinal VEGF expression. Last, we visualized VEGF protein in intestinal tissues of murine and human NEC and control cases by immunohistochemistry.Intestinal VEGF protein and mRNA were significantly decreased in pups exposed to the NEC protocol compared to controls. Hypoxia, cold stress and commensal bacteria, when administered together, significantly downregulated intestinal VEGF expression, while they had no significant effect when given alone. VEGF was localized to a few single intestinal epithelial cells and some cells of the lamina propria and myenteric plexus. VEGF staining was decreased in murine and human NEC intestines when compared to control tissues.Intestinal VEGF protein is reduced in human and experimental NEC. Decreased VEGF production might contribute to NEC pathogenesis.
| S-EPMC4354688 | biostudies-literature
Project description:ObjectivesNecrotizing enterocolitis (NEC) and spontaneous intestinal perforation (SIP) are complications in preterm infants associated with high morbidity, mortality, impaired growth, and neurodevelopmental (ND) outcomes. Few studies have reported growth or ND outcomes of infants born extremely preterm with NEC/SIP beyond early childhood. Here, we compared anthropometric and ND outcomes, at 10 and 15 years, for children with medical NEC, surgical NEC, SIP, and neither NEC nor SIP.MethodsParticipants from the prospective longitudinal extremely low gestational age newborns study were evaluated at ages 10 and 15 years for anthropometrics, neurocognition, attention-deficit/hyperactivity disorder, epilepsy, and gross motor function.ResultsAt age 10 years, 889 children were followed-up (medical NEC = 138, surgical NEC = 33, SIP = 29, no NEC/SIP = 689), and 694 children were followed up-at 15 years. Children with medical NEC had similar weight, BMI, height, and head circumference compared with controls at both 10 and 15 years. At 15 years, children with surgical NEC had lower weight z-score (adjusted β: -0.75, 95% confidence interval [CI]: -1.25 to -0.25), lower BMI z-score (adjusted β: -0.55, 95% CI: -1.09 to -0.01), and lower height z-score (adjusted β: -0.65, 95% CI: -1.16 to -0.14). Children with SIP had lower weight and height z-scores at age 10 years when adjusted for sample attrition, but these differences were not significant when adjusted for confounders. We observed no differences in long-term ND outcomes.ConclusionsSurgical NEC- and SIP-associated growth impairment may persist through late childhood. ND outcomes among school-aged children born extremely preterm with any NEC or SIP are no different from children without NEC/SIP.
| S-EPMC9647591 | biostudies-literature
Project description:Apoptosis among intestinal epithelial cells contributes to necrotizing enterocolitis (NEC), a severe intestinal disease that particularly affects premature infants. β-arrestin-2, an important regulator of G-protein-coupled receptors, is expressed in intestinal epithelial cells, where its activation promotes apoptosis. We found that β-arrestin-2 was overexpressed in both human and murine NEC samples. β-arrestin-2-deficient mice were protected from endoplasmic reticulum stress and NEC development. The endoplasmic reticulum-resident chaperone BiP was found to promote intestinal epithelial cell survival. Pretreatment of intestinal epithelial cells or mice with the BiP inhibitor HA15 increased cell apoptosis and promoted NEC development. β-arrestin-2 bound to BiP and promoted its polyubiquitination and degradation, thereby facilitating the release of the pro-apoptotic molecule BIK from BiP. Silencing β-arrestin-2 downregulated apoptosis by increasing BiP levels, which suppressed endoplasmic reticulum stress. This study suggests that β-arrestin-2 induces NEC development by inhibiting BiP, thereby triggering apoptosis in response to endoplasmic reticulum stress. Thus, novel therapeutic strategies to inhibit β-arrestin-2 may enhance the treatment of NEC.
| S-EPMC6814604 | biostudies-literature
Project description:Although currently available data are variable, it appears that the incidence of surgical necrotizing enterocolitis (NEC) has not decreased significantly over the past decade. Pneumoperitoneum and clinical deterioration despite maximal medical therapy remain the most common indications for operative treatment. Robust studies linking outcomes with specific indications for operation are lacking. Promising biomarkers for severe NEC include fecal calprotectin and S100A12; serum fatty acid-binding protein; and urine biomarkers. Recent advances in ultrasonography make this imaging modality more useful in identifying surgical NEC and near-infrared spectroscopy (NIRS) is being actively studied. Another fairly recent finding is that regionalization of care for infants with NEC likely improves outcomes. The neurodevelopmental outcomes after surgical treatment are known to be poor. A randomized trial near completion will provide robust data regarding neurodevelopmental outcomes after laparotomy versus drainage as the initial operative treatment for severe NEC.
| S-EPMC5777619 | biostudies-other
Project description:Importance:Necrotizing enterocolitis (NEC) in preterm infants is an often-fatal gastrointestinal tract emergency. A robust NEC biomarker that is not confounded by sepsis could improve bedside management, lead to lower morbidity and mortality, and permit patient selection in randomized clinical trials of possible therapeutic approaches. Objective:To evaluate whether aberrant intestinal alkaline phosphatase (IAP) biochemistry in infant stool is a molecular biomarker for NEC and not associated with sepsis. Design, Setting, and Participants:This multicenter diagnostic study enrolled 136 premature infants (gestational age, <37 weeks) in 2 hospitals in Louisiana and 1 hospital in Missouri. Data were collected and analyzed from May 2015 to November 2018. Exposures:Infant stool samples were collected between 24 and 40 or more weeks postconceptual age. Enrolled infants underwent abdominal radiography at physician and hospital site discretion. Main Outcomes and Measures:Enzyme activity and relative abundance of IAP were measured using fluorometric detection and immunoassays, respectively. After measurements were performed, biochemical data were evaluated against clinical entries from infants' hospital stay. Results:Of 136 infants, 68 (50.0%) were male infants, median (interquartile range [IQR]) birth weight was 1050 (790-1350) g, and median (IQR) gestational age was 28.4 (26.0-30.9) weeks. A total of 25 infants (18.4%) were diagnosed with severe NEC, 19 (14.0%) were suspected of having NEC, and 92 (66.9%) did not have NEC; 26 patients (19.1%) were diagnosed with late-onset sepsis, and 14 (10.3%) had other non-gastrointestinal tract infections. For severe NEC, suspected NEC, and no NEC samples, median (IQR) fecal IAP content, relative to the amount of IAP in human small intestinal lysate, was 99.0% (51.0%-187.8%) (95% CI, 54.0%-163.0%), 123.0% (31.0%-224.0%) (95% CI, 31.0%-224.0%), and 4.8% (2.4%-9.8%) (95% CI, 3.4%-5.9%), respectively. For severe NEC, suspected NEC, and no NEC samples, median (IQR) enzyme activity was 183 (56-507) μmol/min/g (95% CI, 63-478 μmol/min/g) of stool protein, 355 (172-608) μmol/min/g (95% CI, 172-608 μmol/min/g) of stool protein, and 613 (210-1465) μmol/min/g (95% CI, 386-723 μmol/min/g) of stool protein, respectively. Mean (SE) area under the receiver operating characteristic curve values for IAP content measurements were 0.97 (0.02) (95% CI, 0.93-1.00; P < .001) at time of severe NEC, 0.97 (0.02) (95% CI, 0.93-1.00; P < .001) at time of suspected NEC, 0.52 (0.07) (95% CI, 0.38-0.66; P = .75) at time of sepsis, and 0.58 (0.08) (95% CI, 0.42-0.75; P = .06) at time of other non-gastrointestinal tract infections. Mean (SE) area under the receiver operating characteristic curve values for IAP activity were 0.76 (0.06) (95% CI, 0.64-0.86; P < .001), 0.62 (0.07) (95% CI, 0.48-0.77; P = .13), 0.52 (0.07) (95% CI, 0.39-0.67; P = .68), and 0.57 (0.08) (95% CI, 0.39-0.69; P = .66), respectively. Conclusions and Relevance:In this diagnostic study, high amounts of IAP protein in stool and low IAP enzyme activity were associated with diagnosis of NEC and may serve as useful biomarkers for NEC. Our findings indicated that IAP biochemistry was uniquely able to distinguish NEC from sepsis.
| S-EPMC6902776 | biostudies-literature