1
|
Wolder D, Swat A, Wolak P, Zmelonek-Znamirowska A, Białek K, Rokita W, Kaczmarek P, Świercz G. Enhanced Diagnostic Capabilities: Ultrasound Imaging of Fetal Alimentary Tract Obstruction with Advanced Imaging Technologies. AMERICAN JOURNAL OF CASE REPORTS 2024; 25:e943419. [PMID: 38444155 DOI: 10.12659/ajcr.943419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
BACKGROUND Congenital malformations of the alimentary tract constitute 5% to 6% of newborn anomalies, with congenital intestinal atresia being a common cause of alimentary tract obstruction. This study explores advanced ultrasound diagnostic possibilities, including 2D, HDlive, HDlive inversion, and HDlive silhouette imaging modes, through the analysis of 3 cases involving duodenal and intestinal obstructions. Congenital malformations of the alimentary tract often present challenges in prenatal diagnosis. The most prevalent defect is congenital intestinal atresia leading to alimentary tract obstruction, with an incidence of approximately 6 in 10 000 births. We focused on advanced ultrasound diagnostic techniques and their applications in 3 cases of duodenal and intestinal obstructions. CASE REPORT Three cases were examined using advanced ultrasound imaging modes. The first patient, diagnosed at week 35 of gestation, revealed stomach and duodenal dilatation. The second, identified at week 32, had the characteristic "double bubble" symptom. The third, at week 31, also had double bubble symptom and underwent repeated amnioreduction procedures. HDlive, HDlive inversion, and HDlive silhouette modes provided intricate visualizations of the affected organs. Prenatal diagnosis of alimentary tract obstruction relies on ultrasound examinations, with nearly 50% of cases being diagnosed before birth. CONCLUSIONS Advanced ultrasound imaging modes, particularly HDlive silhouette, play a crucial role in diagnosing fetal alimentary tract obstruction. These modes offer detailed visualizations and dynamic evaluations, providing essential insights for therapeutic decisions. The study emphasizes the importance of sustained fetal surveillance, a multidisciplinary approach, and delivery in a level III referral center to ensure specialized care for optimal outcomes.
Collapse
Affiliation(s)
- Daniel Wolder
- Department of Obstetrics and Gynecology, Jan Kochanowski University of Kielce, Kielce, Poland
| | - Adrian Swat
- Department of Obstetrics and Gynecology, Regional Hospital in Kielce, Kielce, Poland
| | - Przemysław Wolak
- Department of Obstetrics and Gynecology, Jan Kochanowski University of Kielce, Kielce, Poland
| | | | - Katarzyna Białek
- Department of Obstetrics and Gynecology, Medical University of Łódź, Łódź, Poland
| | - Wojciech Rokita
- Department of Obstetrics and Gynecology, Jan Kochanowski University of Kielce, Kielce, Poland
| | - Piotr Kaczmarek
- Department of Obstetrics and Gynecology, Medical University of Łódź, Łódź, Poland
| | - Grzegorz Świercz
- Department of Obstetrics and Gynecology, Regional Hospital in Kielce, Kielce, Poland
| |
Collapse
|
2
|
Sabbatini S, Ganji N, Chusilp S, Balsamo F, Li B, Pierro A. Intestinal atresia and necrotizing enterocolitis: Embryology and anatomy. Semin Pediatr Surg 2022; 31:151234. [PMID: 36417784 DOI: 10.1016/j.sempedsurg.2022.151234] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The primitive gut originates at week 3 of gestation from the endoderm, with posterior incorporation of the remaining embryo layers. Wnt, Notch and TLR4 pathways have been shown to play central roles in the correct development of the intestine. The classical hypothesis for intestinal atresia development consists of failure in bowel recanalization or a vascular accident with secondary bowel reabsorption. These have been challenged due to the high frequency of associated malformations, and furthermore, with the discovery of molecular pathways and genes involved in bowel formation and correlated defects producing atresia. Necrotizing enterocolitis (NEC) has a multifactorial pathogenesis with prematurity being the most important risk factor; therefore, bowel immaturity plays a central role in NEC. Some of the same molecular pathways involved in gut maturation have been found to correlate with the predisposition of the immature bowel to develop the pathological findings seen in NEC.
Collapse
Affiliation(s)
- S Sabbatini
- Translational Medicine Program, The Hospital for Sick Children, Toronto
| | - N Ganji
- Translational Medicine Program, The Hospital for Sick Children, Toronto
| | - S Chusilp
- Translational Medicine Program, The Hospital for Sick Children, Toronto
| | - F Balsamo
- Translational Medicine Program, The Hospital for Sick Children, Toronto
| | - B Li
- Translational Medicine Program, The Hospital for Sick Children, Toronto
| | - A Pierro
- Translational Medicine Program, The Hospital for Sick Children, Toronto; Division of General and Thoracic Surgery, The Hospital for Sick Children, Toronto.
| |
Collapse
|
3
|
Kostouros A, Koliarakis I, Natsis K, Spandidos DA, Tsatsakis A, Tsiaoussis J. Large intestine embryogenesis: Molecular pathways and related disorders (Review). Int J Mol Med 2020; 46:27-57. [PMID: 32319546 PMCID: PMC7255481 DOI: 10.3892/ijmm.2020.4583] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 04/08/2020] [Indexed: 02/07/2023] Open
Abstract
The large intestine, part of the gastrointestinal tract (GI), is composed of all three germ layers, namely the endoderm, the mesoderm and the ectoderm, forming the epithelium, the smooth muscle layers and the enteric nervous system, respectively. Since gastrulation, these layers develop simultaneously during embryogenesis, signaling to each other continuously until adult age. Two invaginations, the anterior intestinal portal (AIP) and the caudal/posterior intestinal portal (CIP), elongate and fuse, creating the primitive gut tube, which is then patterned along the antero‑posterior (AP) axis and the radial (RAD) axis in the context of left‑right (LR) asymmetry. These events lead to the formation of three distinct regions, the foregut, midgut and hindgut. All the above‑mentioned phenomena are under strict control from various molecular pathways, which are critical for the normal intestinal development and function. Specifically, the intestinal epithelium constitutes a constantly developing tissue, deriving from the progenitor stem cells at the bottom of the intestinal crypt. Epithelial differentiation strongly depends on the crosstalk with the adjacent mesoderm. Major molecular pathways that are implicated in the embryogenesis of the large intestine include the canonical and non‑canonical wingless‑related integration site (Wnt), bone morphogenetic protein (BMP), Notch and hedgehog systems. The aberrant regulation of these pathways inevitably leads to several intestinal malformation syndromes, such as atresia, stenosis, or agangliosis. Novel theories, involving the regulation and homeostasis of intestinal stem cells, suggest an embryological basis for the pathogenesis of colorectal cancer (CRC). Thus, the present review article summarizes the diverse roles of these molecular factors in intestinal embryogenesis and related disorders.
Collapse
Affiliation(s)
- Antonios Kostouros
- Laboratory of Anatomy-Histology-Embryology, Medical School, University of Crete, 71110 Heraklion
| | - Ioannis Koliarakis
- Laboratory of Anatomy-Histology-Embryology, Medical School, University of Crete, 71110 Heraklion
| | - Konstantinos Natsis
- Department of Anatomy and Surgical Anatomy, Medical School, Aristotle University of Thessaloniki, 54124 Thessaloniki
| | | | - Aristidis Tsatsakis
- Laboratory of Toxicology, Medical School, University of Crete, 71409 Heraklion, Greece
| | - John Tsiaoussis
- Laboratory of Anatomy-Histology-Embryology, Medical School, University of Crete, 71110 Heraklion
| |
Collapse
|
4
|
Jones MLM, Sarila G, Chapuis P, Hutson JM, King SK, Teague WJ. The Role of Fibroblast Growth Factor 10 Signaling in Duodenal Atresia. Front Pharmacol 2020; 11:250. [PMID: 32210824 PMCID: PMC7076179 DOI: 10.3389/fphar.2020.00250] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 02/24/2020] [Indexed: 11/24/2022] Open
Abstract
Introduction Duodenal atresia (DA) is a congenital bowel obstruction requiring major surgery in the first week of life. Three morphological phenotypes are described, reflecting increasing degrees of obstruction and discontinuity of the duodenum. The cause of DA is not known. Tandler’s original “solid cord” hypothesis conflicts with recent biological evidence, and is unable to account for differing DA types. In humans, a genetic etiology is supported by the association between Trisomy 21 and DA, and reports of familial inheritance patterns. Interruption of FGF10/FGFR2b signaling is the best demonstrated genetic link to DA in mice, with 35–75% of homozygous knockout embryos developing DA. Purpose This review examines the current evidence surrounding the etiology of DA. We focus on research regarding FGF10/FGFR2b signaling and its role in duodenal and other intestinal atresia. Further, we outline planned future research in this area, that we consider necessary to validate and better understand this murine model in order to successfully translate this research into clinical practice. Conclusion Determining the etiology of DA in humans is a clinical and scientific imperative. Fgf10/Fgfr2b murine models represent current science’s best key to unlocking this mystery. However, further research is required to understand the complex role of FGF10/FGFR2b signaling in DA development. Such complexity is expected, given the lethality of their associated defects makes ubiquitous interruption of either Fgf10 or Fgfr2b genes an unlikely cause of DA in humans. Rather, local or tissue-specific mutation in Fgf10, Fgfr2b, or their downstream targets, is the hypothesized basis of DA etiology.
Collapse
Affiliation(s)
- Matthew L M Jones
- F. Douglas Stephens Surgical Research Laboratory, Murdoch Children's Research Institute, Melbourne, VIC, Australia.,Discipline of Surgery, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia.,Department of Paediatric Surgery, The Royal Children's Hospital, Melbourne, VIC, Australia
| | - Gulcan Sarila
- F. Douglas Stephens Surgical Research Laboratory, Murdoch Children's Research Institute, Melbourne, VIC, Australia
| | - Pierre Chapuis
- Discipline of Surgery, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia
| | - John M Hutson
- F. Douglas Stephens Surgical Research Laboratory, Murdoch Children's Research Institute, Melbourne, VIC, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, VIC, Australia.,Department of Urology, The Royal Children's Hospital Melbourne, Melbourne, VIC, Australia
| | - Sebastian K King
- F. Douglas Stephens Surgical Research Laboratory, Murdoch Children's Research Institute, Melbourne, VIC, Australia.,Discipline of Surgery, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia.,Department of Paediatric Surgery, The Royal Children's Hospital, Melbourne, VIC, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, VIC, Australia
| | - Warwick J Teague
- F. Douglas Stephens Surgical Research Laboratory, Murdoch Children's Research Institute, Melbourne, VIC, Australia.,Discipline of Surgery, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia.,Department of Paediatric Surgery, The Royal Children's Hospital, Melbourne, VIC, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, VIC, Australia
| |
Collapse
|
5
|
Kowalkowski A, Zaremba KM, Rogers AP, Hoffman OR, Turco AE, Nichol PF. Lack of discreet colocalization of epithelial apoptosis to the atretic precursor in the colon of the Fibroblast growth factor receptor 2IIIb mouse and staining consistent with cellular movement suggest a revised model of atresia formation. Dev Dyn 2020; 249:741-753. [PMID: 32100913 DOI: 10.1002/dvdy.164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 12/30/2019] [Accepted: 01/27/2020] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Colonic atresias in the Fibroblast growth factor receptor 2IIIb (Fgfr2IIIb) mouse model have been attributed to increased epithelial apoptosis and decreased epithelial proliferation at embryonic day (E) 10.5. We therefore hypothesized that these processes would colocalize to the distal colon where atresias occur (atretic precursor) and would be excluded or minimized from the proximal colon and small intestine. RESULTS We observed a global increase in intestinal epithelial apoptosis in Fgfr2IIIb -/- intestines from E9.5 to E10.5 that did not colocalize to the atretic precursor. Additionally, epithelial proliferations rates in Fgfr2IIIb -/- intestines were statistically indistinguishable to that of controls at E10.5 and E11.5. At E11.5 distal colonic epithelial cells in mutants failed to assume the expected pseudostratified columnar architecture and the continuity of the adjacent basal lamina was disrupted. Individual E-cadherin-positive cells were observed in the colonic mesenchyme. CONCLUSIONS Our observations suggest that alterations in proliferation and apoptosis alone are insufficient to account for intestinal atresias and that these defects may arise from both a failure of distal colonic epithelial cells to develop normally and local disruptions in basal lamina architecture.
Collapse
Affiliation(s)
- Anna Kowalkowski
- Surgery Department, University of Wisconsin, Madison, Wisconsin, USA
| | | | - Andrew P Rogers
- Surgery Department, University of Wisconsin, Madison, Wisconsin, USA
| | - Olivia R Hoffman
- Surgery Department, University of Wisconsin, Madison, Wisconsin, USA
| | - Anne E Turco
- Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin, USA
| | - Peter F Nichol
- Surgery Department, University of Wisconsin, Madison, Wisconsin, USA
| |
Collapse
|
6
|
Teague WJ, Jones MLM, Hawkey L, Smyth IM, Catubig A, King SK, Sarila G, Li R, Hutson JM. FGF10 and the Mystery of Duodenal Atresia in Humans. Front Genet 2018; 9:530. [PMID: 30473704 PMCID: PMC6238159 DOI: 10.3389/fgene.2018.00530] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 10/22/2018] [Indexed: 11/30/2022] Open
Abstract
Background: Duodenal atresia (DA) is a congenital obstruction of the duodenum, which affects 1 in 7000 pregnancies and requires major surgery in the 1st days of life. Three morphological DA types are described. In humans, the association between DA and Down syndrome suggests an underlying, albeit elusive, genetic etiology. In mice, interruption of fibroblast growth factor 10 (Fgf10) gene signaling results in DA in 30–50% of embryos, supporting a genetic etiology. This study aims to validate the spectrum of DA in two novel strains of Fgf10 knock-out mice, in preparation for future and translational research. Methods: Two novel CRISPR Fgf10 knock-out mouse strains were derived and embryos generated by heterozygous plug-mating. E15.5–E19.5 embryos were genotyped with respect to Fgf10 and micro-dissected to determine the presence and type of DA. Results: One twenty seven embryos (32 wild-type, 34 heterozygous, 61 null) were analyzed. No wild-type or heterozygous embryos had DA. However, 74% of Fgf10 null embryos had DA (49% type 1, 18% type 2, and 33% type 3). Conclusion: Our CRISPR-derived strains showed higher penetrance of DA due to single-gene deletion of Fgf10 in mice than previously reported. Further, the DA type distribution in these mice more closely reiterated that observed in humans. Future experiments will document RNA and protein expression of FGF10 and its key downstream signaling targets in normal and atretic duodenum. This includes exploitation of modern, high-fidelity developmental tools, e.g., Fgf10flox/+–tomatoflox/flox mice.
Collapse
Affiliation(s)
- Warwick J Teague
- F. Douglas Stephens Surgical Research Laboratory, Murdoch Children's Research Institute, Melbourne, VIC, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, VIC, Australia.,Discipline of Surgery, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia.,Department of Paediatric Surgery, The Royal Children's Hospital, Melbourne, VIC, Australia
| | - Matthew L M Jones
- F. Douglas Stephens Surgical Research Laboratory, Murdoch Children's Research Institute, Melbourne, VIC, Australia.,Discipline of Surgery, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia.,Department of Paediatric Surgery, The Royal Children's Hospital, Melbourne, VIC, Australia
| | - Leanne Hawkey
- Australian Phenomics Network, Department of Anatomy and Developmental Biology, Monash University, Melbourne, VIC, Australia
| | - Ian M Smyth
- Australian Phenomics Network, Department of Anatomy and Developmental Biology, Monash University, Melbourne, VIC, Australia.,Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia.,Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
| | - Angelique Catubig
- F. Douglas Stephens Surgical Research Laboratory, Murdoch Children's Research Institute, Melbourne, VIC, Australia
| | - Sebastian K King
- F. Douglas Stephens Surgical Research Laboratory, Murdoch Children's Research Institute, Melbourne, VIC, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, VIC, Australia.,Department of Paediatric Surgery, The Royal Children's Hospital, Melbourne, VIC, Australia.,Department of Gastroenterology and Clinical Nutrition, The Royal Children's Hospital, Melbourne, VIC, Australia
| | - Gulcan Sarila
- F. Douglas Stephens Surgical Research Laboratory, Murdoch Children's Research Institute, Melbourne, VIC, Australia
| | - Ruili Li
- F. Douglas Stephens Surgical Research Laboratory, Murdoch Children's Research Institute, Melbourne, VIC, Australia
| | - John M Hutson
- F. Douglas Stephens Surgical Research Laboratory, Murdoch Children's Research Institute, Melbourne, VIC, Australia.,Department of Paediatrics, The University of Melbourne, Melbourne, VIC, Australia.,Department of Urology, The Royal Children's Hospital, Melbourne, VIC, Australia
| |
Collapse
|
7
|
Celli J. Genetics of gastrointestinal atresias. Eur J Med Genet 2014; 57:424-39. [DOI: 10.1016/j.ejmg.2014.06.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Accepted: 06/21/2014] [Indexed: 01/04/2023]
|
8
|
Schoppel K, Durkin ET, Kim HB, Chen C. Delayed presentation of bowel obstruction in a patient with Trisomy 21: A novel method for addressing intestinal webs. JOURNAL OF PEDIATRIC SURGERY CASE REPORTS 2014. [DOI: 10.1016/j.epsc.2014.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|
9
|
Fragoso AC, Martinez L, Estevão-Costa J, Tovar JA. Maternal hyperthyroidism increases the prevalence of foregut atresias in fetal rats exposed to adriamycin. Pediatr Surg Int 2014; 30:151-7. [PMID: 24363086 DOI: 10.1007/s00383-013-3445-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
PURPOSE Gastrointestinal malformations such as esophageal atresia with tracheoesophageal fistula (EA/TEF) and duodenal atresia (DA) have been reported in infants born to hyperthyroid mothers or with congenital hypothyroidism. The present study aimed to test whether maternal thyroid status during embryonic foregut division has any influence on the prevalence of EA/TEF and DA in an accepted rat model of these malformations. METHODS Pregnant rats received either vehicle or 1.75 mg/kg i.p. adriamycin on gestational days 7, 8 and 9. Transient maternal hyper or hypothyroidism was induced by oral administration of levothyroxine (LT4, 50 μg/kg/day) or propylthiouracil (PTU, 2 mg/kg/day), respectively, on days 7 to 12 of gestation. Plasma cholesterol, total T3, free T4 and TSH were measured at gestational days 7, 12, and 21. At the end of gestation, the mothers were sacrificed and embryo-fetal mortality was recorded. Fetuses were dissected to determine the prevalence of esophageal and intestinal atresias. RESULTS At gestational day 12, mothers treated with LT4 or PTU had hyper or hypothyroid status, respectively; plasma cholesterol levels were similar. In the adriamycin-exposed fetuses from hyperthyroid mothers, the embryonal resorption rate and the prevalence of both EA/TEF and DA were significantly higher than in the other groups; maternal hypothyroidism during the same period did not have significant effect on the prevalence of atresias. CONCLUSIONS Maternal hyperthyroidism during the embryonic window corresponding to foregut cleavage increased the prevalence of both EA/TEF and duodenal atresia in fetal rats exposed to adriamycin. This suggests that maternal thyroid hormone status might be involved in the pathogenesis of foregut atresias and invites further research on this likely clinically relevant issue in humans.
Collapse
Affiliation(s)
- Ana Catarina Fragoso
- INGEMM and IdiPaz Research Laboratory, Department of Pediatric Surgery, Hospital Universitario La Paz, 28046, Madrid, Spain
| | | | | | | |
Collapse
|
10
|
Reeder AL, Botham RA, Zaremba KM, Nichol PF. Haploinsufficiency of retinaldehyde dehydrogenase 2 decreases the severity and incidence of duodenal atresia in the fibroblast growth factor receptor 2IIIb-/- mouse model. Surgery 2012; 152:768-75; discussion 775-6. [PMID: 23021139 DOI: 10.1016/j.surg.2012.07.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Accepted: 07/13/2012] [Indexed: 11/19/2022]
Abstract
BACKGROUND Homozygous null mutation of the fibroblast growth factor receptor 2IIIb (Fgfr2IIIb) gene in mice results in 42% of embryos developing duodenal atresias. Retinaldehyde dehydrogenase 2 (Raldh2, a gene critical for the generation of retinoic acid) is expressed in the mouse duodenum during the temporal window when duodenal atresias form. Raldh2 is critical for the normal development of the pancreatoduodenal region; therefore, we were interested in the effect of a Raldh2 mutation on duodenal atresia formation. To test this, we rendered Fgfr2IIIb(-/-) embryos haploinsufficient for the Raldh2 and examined these embryos for the incidence and severity of duodenal atresia. METHODS Control embryos, Fgfr2IIIb(-/-) mutants, and Fgfr2IIIb(-/-); Raldh2(+/-) mutants were harvested at embryonic day 18.5, genotyped, and fixed overnight. Intestinal tracts were isolated. The type and severity of duodenal atresia was documented. RESULTS A total of 97 Fgfr2IIIb(-/-) embryos were studied; 44 had duodenal atresias, and 41 of these presented as type III. In the 70 Fgfr2IIIb(-/-); Raldh2(+/-) embryos studied, a lesser incidence of duodenal atresia was seen (15 of 70; P = .0017; Fisher exact test). Atresia severity was also decreased; there were 12 embryos with type I atresias, 3 with type II atresias, and 0 with type III atresias (P < 2.81E-013; Fisher exact test). CONCLUSION Haploinsufficiency of Raldh2 decreases the incidence and severity of duodenal atresia in the Fgfr2IIIb(-/-) model. The ability to alter defect severity through manipulation of a single gene in a specific genetic background has potentially important implications for understanding the mechanisms by which intestinal atresias arise.
Collapse
Affiliation(s)
- Amy L Reeder
- Department of Surgery, Section of Pediatric Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | | | | | | |
Collapse
|
11
|
Reeder AL, Botham RA, Franco M, Zaremba KM, Nichol PF. Formation of intestinal atresias in the Fgfr2IIIb-/- mice is not associated with defects in notochord development or alterations in Shh expression. J Surg Res 2012; 177:139-45. [PMID: 22572615 DOI: 10.1016/j.jss.2012.04.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2012] [Revised: 03/24/2012] [Accepted: 04/11/2012] [Indexed: 10/28/2022]
Abstract
PURPOSE The etiology of intestinal atresia remains elusive but has been ascribed to a number of possible events including in utero vascular accidents, failure of recanalization of the intestinal lumen, and mechanical compression. Another such event that has been postulated to be a cause in atresia formation is disruption in notochord development. This hypothesis arose from clinical observations of notochord abnormalities in patients with intestinal atresias as well as abnormal notochord development observed in a pharmacologic animal model of intestinal atresia. Atresias in this model result from in utero exposure to Adriamycin, wherein notochord defects were noted in up to 80% of embryos that manifested intestinal atresias. Embryos with notochord abnormalities were observed to have ectopic expression of Sonic Hedgehog (Shh), which in turn was postulated to be causative in atresia formation. We were interested in determining whether disruptions in notochord development or Shh expression occurred in an established genetic model of intestinal atresia and used the fibroblast growth factor receptor 2IIIb homozygous mutant (Fgfr2IIIb-/-) mouse model. These embryos develop colonic atresias (100% penetrance) and duodenal atresias (42% penetrance). METHODS Wild-type and Fgfr2IIIb-/- mouse embryos were harvested at embryonic day (E) 10.5, E11.5, E12.5, and E13.5. Whole-mount in situ hybridization was performed on E10.5 embryos for Shh. Embryos at each time point were harvested and sectioned for hematoxylin-eosin staining. Sections were photographed specifically for the notochord and resulting images reconstructed in 3-D using Amira software. Colons were isolated from wild-type and Fgfr2IIIb-/- embryos at E10.5, then cultured for 48 hours in Matrigel with FGF10 in the presence or absence of exogenous Shh protein. Explants were harvested, fixed in formalin, and photographed. RESULTS Fgfr2IIIb-/- mouse embryos exhibit no disruptions in Shh expression at E10.5, when the first events in atresia formation are known to occur. Three-dimensional reconstructions failed to demonstrate any anatomical disruptions in the notochord by discontinuity or excessive branching. Culture of wild-type intestines in the presence of Shh failed to induce atresia formation in either the duodenum or colon. Cultured Fgfr2IIIb-/- intestines developed atresias of the colon in either the presence or absence of Shh protein. CONCLUSIONS Although disruptions in notochord development can be associated with intestinal atresia formation, in the Fgfr2IIIb-/- genetic animal model neither disruptions in notochord development nor the presence of exogenous Shh protein are causative in the formation of these defects.
Collapse
Affiliation(s)
- Amy L Reeder
- University of Wisconsin SMPH-Department of Surgery, Section of Pediatric Surgery, Madison, Wisconsin 53792, USA
| | | | | | | | | |
Collapse
|