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- Högberg, Niclas, 1979-, et al.
(author)
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Genes regulating tight junctions and cell adhesion are altered in early experimental necrotizing enterocolitis
- 2013
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In: Journal of Pediatric Surgery. - : Elsevier BV. - 0022-3468 .- 1531-5037. ; 48:11, s. 2308-2312
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Journal article (peer-reviewed)abstract
- Background/purpose:Necrotizing enterocolitis (NEC) represents one of the gravest complications in preterm infants and carries significant morbidity and mortality. Increased intestinal permeability may play an important role in the pathogenesis of NEC. In this study we investigated the genes regulating structural proteins such as tight junctions (TJ) and cell adhesion in a neonatal rat model of early NEC, as well as the expression of TJ proteins by immunohistochemistry staining.Methods:The studies were performed on Sprague-Dawley rat pups. Experimental NEC was induced using hypoxia/reoxygenation treatment on day 1 after birth. Intestinal specimens from the ileum were obtained, mRNA was purified and the transcriptome was analyzed using microarray. Immunohistochemistry staining was performed for TJ proteins.Results:We found several TJ genes such as claudins 1, 8, 14, 15 and gap junction protein to be affected. Immunohistochemistry staining for TJ protein claudin-1 revealed decreased levels in experimental NEC compared to controls. Alterations in genes involved in the inflammatory response was confirmed, along with several genes regulating proteins used as biomarkers for NEC.Conclusion:This study indicates that tight junctions and cell adhesion may play a critical role in the pathogenesis of early experimental NEC. Better understanding of the pathogenesis of NEC may lead to novel strategies for the prevention and treatment of NEC.
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| 2. |
- Högberg, Niclas, 1979-, et al.
(author)
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Intestinal ischemia measured by intraluminal microdialysis
- 2012
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In: Scandinavian Journal of Clinical and Laboratory Investigation. - : Informa UK Limited. - 0036-5513 .- 1502-7686. ; 72:1, s. 59-66
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Journal article (peer-reviewed)abstract
- Objective. To evaluate the possibility of detecting intestinal ischemia by intraluminal microdialysis and comparing the ileum and colon. Methods. The studies were performed on male Sprague-Dawley rats. In the fi rst part of the study, microdialysis catheters were placed in the sigmoid part of the colon and in the subcutaneous adipose tissue. In the second part of the study, microdialysis catheters were placed in the lumen of the ileum and the colon. The infrarenal aorta was clamped proximal to the cranial mesenteric artery. Microdialysate levels of glucose, lactate, pyruvate and glycerol were measured. Intestinal specimens were removed at the end of the ischemic period for microscopic evaluation. Results. Intraluminal microdialysis could detect early signs of ischemic injury in the ileum, as well as in the colon, with a marked increase of lactate, lactate/pyruvate ratio and glycerol. The increased levels of intraluminal glycerol showed a positive correlation to prolonged ischemia and to higher degrees of intestinal damage. Conclusion. Intraluminal measurement of glycerol is a good marker for intestinal ischemia. Intraluminal microdialysis in the colon is easily accessible through the rectum, and ay prove to be a valuable clinical tool for diagnosing intestinal ischemia.
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| 3. |
- Högberg, Niclas, 1979-, et al.
(author)
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Intraluminal intestinal microdialysis detects markers of hypoxia and cell damage in experimental necrotizing enterocolitis
- 2012
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In: Journal of Pediatric Surgery. - : Elsevier BV. - 0022-3468 .- 1531-5037. ; 47:9, s. 1646-1651
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Journal article (peer-reviewed)abstract
- BACKGROUND/PURPOSE:Necrotizing enterocolitis (NEC) represents one of the gravest complications in premature infants and carries significant morbidity and mortality. There is a great need for improved diagnostic methods to reduce the severity and incidence of NEC. The aim of the study was to investigate if intraluminal microdialysis can detect intestinal ischemia in newborn rats with induced experimental NEC.METHODS:The studies were performed on 1-day-old Sprague-Dawley rat pups. Experimental NEC was induced using hypoxia/reoxygenation treatment. Microdialysis catheters were rectally inserted and placed in the rectosigmoid part of the colon. Microdialysate levels of glucose, lactate, pyruvate, and glycerol were measured. Intestinal specimens were collected at the end of the experiments for microscopic evaluation.RESULTS:Intraluminal microdialysis revealed signs of intestinal hypoxia and cellular damage, with a marked increase of lactate and glycerol. Microscopic evaluation confirmed intestinal damage in the NEC group.CONCLUSION:Intraluminal microdialysis can detect intestinal hypoxic stress and mucosal cell membrane decay in a rat model of NEC. Intestinal intraluminal microdialysis is easily accessible through the rectum and may be a useful noninvasive complement to other methods in the assessment of NEC.
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