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Necrotizing enterocolitis (NEC) is the leading cause of morbidity and mortality in premature infants. One of the most devastating complications of NEC is the development of NEC-induced brain injury, which manifests as impaired cognition that persists beyond infancy and which represents a proinflammatory activation of the gut-brain axis. Given that oral administration of the human milk oligosaccharides (HMOs) 20-fucosyllactose (20-FL) and 60-sialyslactose (60-SL) significantly reduced intestinal inflammation in mice, we hypothesized that oral administration of these HMOs would reduce NEC-induced brain injury and sought to determine the mechanisms involved. We now show that the administration of either 20-FL or 60-SL significantly attenuated NECinduced brain injury, reversed myelin loss in the corpus callosum and midbrain of newborn mice, and prevented the impaired cognition observed in mice with NEC-induced brain injury. In seeking to define the mechanisms involved, 20-FL or 60-SL administration resulted in a restoration of the blood-brain barrier in newborn mice and also had a direct anti-inflammatory effect on the brain as revealed through the study of brain organoids. Metabolites of 20-FL were detected in the infant mouse brain by nuclear magnetic resonance (NMR), whereas intact 20-FL was not. Strikingly, the beneficial effects of 20-FL or 60-SL against NEC-induced brain injury required the release of the neurotrophic factor brain-derived neurotrophic factor (BDNF), as mice lacking BDNF were not protected by these HMOs from the development of NEC-induced brain injury. Taken in aggregate, these findings reveal that the HMOs 20-FL and 60-SL interrupt the gut-brain inflammatory axis and reduce the risk of NEC-induced brain injury. [ABSTRACT FROM AUTHOR]

Y-27632 inhibits Rho-associated coiled-coil-containing protein kinase (ROCK) signaling, which is involved in various embryonic developmental processes, including angiogenesis, by controlling actin cytoskeleton assembly and cell contractility. Administration of Y-27632 impairs cytoskeletal arrangements in post-gastrulation chick embryos, leading to ventral body wall defects (VBWDs). Impaired angiogenesis has been hypothesized to contribute to VBWDs. ROCK is essential in transmitting signals downstream of vascular endothelial growth factor (VEGF). VEGF-mediated angiogenesis induces gene expressions and alterations of the actin cytoskeleton upon binding to VEGF receptors (VEGFRs). The aim of this study was to investigate effects of Y-27632 on angiogenesis in post-gastrulation chick embryos during early embryogenesis. After 60 h incubation, embryos in shell-less culture were treated with Y-27632 or vehicle for controls. Y-27632-treated embryos showed reduced extra-embryonic blood vessel formation with impaired circulation of the yolk sac, confirmed by fractal analysis. Western blot confirmed impaired ROCK downstream signaling by decreased expression of phosphorylated myosin light chain. Interestingly, RT-PCR demonstrated increased gene expression of VEGF and VEGFR-2 1 h post-treatment. Protein levels of VEGF were higher in Y-27632-treated embryos at 8 h following treatment, whereas no difference was seen in membranes. We hypothesize that administration of Y-27632 impairs vessel formation during angiogenesis, which may contribute to failure of VWB closure, causing VBWDs. [ABSTRACT FROM AUTHOR]

Background Caveolin-1 (Cav-1) exerts major regulatory functions on intracellular signaling pathways originating at the plasma membrane. Cav-1 is a key regulator in adverse lung remodeling and the development of pulmonary hypertension (PH) regulating vasomotor tone through its ability to reduce nitric oxide (NO) production. This low-output endothelial NO synthase (eNOS) derived NO maintains normal pulmonary vascular homeostasis. Cav-1 deficiency leads to increased bioavailability of NO, which has been linked to increased nitrosative stress. Inhibition of eNOS reduced oxidant production and reversed PH, supporting the concept that Cav-1 regulation of eNOS activity is crucial to endothelial homeostasis in lungs. We designed this study to investigate the hypothesis that expression of Cav-1 is downregulated while eNOS expression is upregulated by the pulmonary endothelium in the nitrofen-induced congenital diaphragmatic hernia (CDH). Methods Pregnant rats were exposed to nitrofen or vehicle on day 9.5 (D9.5). Fetuses were sacrificed on D21 and divided into nitrofen and control groups. Quantitative real-time polymerase chain reaction, Western blotting, and confocal immunofluorescence were performed to determine pulmonary gene expression levels and protein expression of Cav-1 and eNOS. Results Pulmonary Cav-1 gene expression levels were significantly decreased, while eNOS gene expression was significantly increased in nitrofen-induced CDH(+). Western blotting and confocal microscopy revealed decreased pulmonary Cav-1 protein expression, while eNOS protein expression was increased in CDH(+) compared to controls. Conclusion The striking evidence of markedly decreased gene and protein expression of Cav-1 with concurrently increased eNOS gene and protein expression in the pulmonary vasculature suggests that activation of eNOS secondary to Cav-1 deficiency may play an important role in the pathogenesis of PH in the nitrofen-induced CDH [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Congenital diaphragmatic hernia (CDH) is attributed to severe pulmonary hypoplasia and pulmonary hypertension (PH). PH is characterized by structural changes resulting in vascular remodeling. Serotonin, a potent vasoconstrictor, plays a central role in the development of PH. It exerts its constricting effects on the vessels via Serotonin receptor 2A (5-HT2A) and induces pulmonary smooth muscle cell proliferation via the serotonin transporter (5-HTT). This study was designed to investigate expressions of 5-HT2A and 5-HTT in the pulmonary vasculature of rats with nitrofen-induced CDH. Methods: Rats were exposed to nitrofen or vehicle on D9. Fetuses were sacrificed on D21 and divided into nitrofen and control group (n =32). Pulmonary RNA was extracted and mRNA level of 5HT2A was determined by qRT-PCR. Protein expression of 5HT2A and 5-HTT was investigated by western blotting. Confocal immunofluorescence double-staining for 5-HT2A, 5-HTT, and alpha smooth muscle actin were performed. Results: Pulmonary 5-HT2A gene expression levels were significantly increased in nitrofen-induced CDH compared to controls. Western blotting and confocal microscopy confirmed increased pulmonary protein expression in CDH lungs compared to controls. Conclusion: Increased gene and protein expression of 5HT2A and 5-HTT in the pulmonary vasculature of nitrofen-induced CDH lungs suggest that 5HT2A and 5-HTT are important mediators of PH in nitrofen-induced CDH. [Copyright &y& Elsevier]

Purpose: Anorectal malformations (ARM) are one of the most challenging congenital malformations in pediatric surgery. We aimed to assess the research activity on ARM over the last five decades. Methods: Data on original research publications were retrieved from the Web of Science Core Collection (1970–2020), and analyzed for countries, authors, scientific journals, and top-ten papers. Scientific quantity was assessed by the number of publications. Research quality was estimated from the number of citations, average citation rate per item (ACI), and h-index. Results: A total number of 1595 articles with 19,419 citations (ACI = 12.2; h-index = 54) were identified. The annual number of publications and citations significantly increased over time (p < 0.0001). The USA (n = 386; 24.2%), Japan (n = 153; 9.6%), and China (n = 137; 8.6%) were the most productive countries; and the USA (n = 7850; ACI = 20.3; h-index = 44), Japan (n = 1937; ACI = 12.6; h-index = 21), and the Netherlands (n = 1318; ACI = 17.3; h-index = 22) were the top cited countries. Articles were preferentially published in JPS (n = 391; 24.5%), PSI (n = 181; 11.3%), and EJPS (n = 56; 3.5%). Top-ten cited papers focused on classification (n = 1), surgical technique (n = 3), associated syndromes (n = 2), postoperative outcome (n = 3), and basic research (n = 1). Conclusion: This bibliometric study provides valuable insights into the global development of ARM research, and shows that clinical studies and international collaborations dominate in this field. [ABSTRACT FROM AUTHOR]

The pyridine derivative Y-27632 inhibits Rho-associated coiled-coil-containing protein kinase (ROCK) signaling, which is involved in numerous developmental processes during embryogenesis, primarily by controlling actin-cytoskeleton assembly and cell contractility. Somite formation requires rearrangement of the cytoskeleton and assists in major morphological mechanisms, including ventral body wall formation. Administration of Y-27632 impairs cytoskeletal arrangements in post-gastrulation chick embryos leading to ventral body wall defects (VBWD) at later stages of development. The aim of this study was to investigate the effect of Y-27632 on somite development in post-gastrulation chick embryos during early embryogenesis. After 60 h incubation, embryos in shell-less culture were treated with Y-27632 or vehicle for controls. Following administration, abnormality rates were assessed. In treatment groups, embryos showed a kinked longitudinal body axis. Western blot confirmed impaired ROCK downstream signaling by decreased expression of phosphorylated cofilin-2. Histology, Lysotracker studies and RT-PCR demonstrated increased cell death in somites, the neural tube and the ectoderm. RT-PCR and Western blot of factors known to be involved during somitogenesis revealed reduced expression in the treatment group compared to controls. We hypothesize that administration of Y-27632 disrupts somite development causing axial kinking and embryo malformation, which may lead to VBWD. • Y-27632 leads to morphological abnormalities in post-gastrulation chick embryos. • Gross malformations are associated with inhibition of ROCK downstream signaling. • Lysotracker studies showed increased cell death in somites after Y-27632 treatment. • Factors essential during somitogenesis are reduced in Y-27632 treated chick embryos. [ABSTRACT FROM AUTHOR]