title: Spatiotemporal distribution of extracellular matrix changes during mouse duodenojejunal flexure formation.
abstract: Although gut flexures characterize gut morphology, the mechanisms underlying flexure formation remain obscure. Previously, we analyzed the mouse duodenojejunal flexure (DJF) as a model for its formation and reported asymmetric morphologies between the inner and outer bending sides of the fetal mouse DJF, implying their contribution to DJF formation. We now present the extracellular matrix (ECM) as an important factor for gut morphogenesis. We investigate ECM distribution during mouse DJF formation by histological techniques. In the intercellular space of the gut wall, high Alcian-Blue positivity for proteoglycans shifted from the outer to the inner side of the gut wall during DJF formation. Immunopositivity for fibronectin, collagen I, or pan-tenascin was higher at the inner than at the outer side. Collagen IV and laminins localized to the epithelial basement membrane. Beneath the mesothelium at the pre-formation stage, collagen IV and laminin immunopositivity showed inverse results, corresponding to the different cellular characteristics at this site. At the post-formation stage, however, laminin positivity beneath the mesothelium was the reverse of that observed during the pre-formation stage. High immunopositivity for collagen IV and laminins at the inner gut wall mesenchyme of the post-formation DJF implied a different blood vessel distribution. We conclude that ECM distribution changes spatiotemporally during mouse DJF formation, indicating ECM association with the establishment of asymmetric morphologies during this process.
authors.affiliation: Laboratory of Anatomy, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan.
authors.forename: Sawa
authors.initials: S
authors.lastname: Onouchi
authors.affiliation: Laboratory of Anatomy, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Ichii
authors.affiliation: Laboratory of Anatomy, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan.|Section of Biological Safety Research, Chitose Laboratory, Japan Food Research Laboratories, Chitose, Hokkaido, Japan.
authors.forename: Teppei
authors.initials: T
authors.lastname: Nakamura
authors.affiliation: Laboratory of Anatomy, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan.|Department of Histology and Cytology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
authors.forename: Yaser Hosny Ali
authors.initials: YH
authors.lastname: Elewa
authors.affiliation: Laboratory of Anatomy, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan. y-kon@vetmed.hokudai.ac.jp.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kon
mesh_terms: D000818:Animals; D024042:Collagen Type I / Q000378:metabolism; D004386:Duodenum / Q000196:embryology* / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism*; D005260:Female; D005353:Fibronectins; D007583:Jejunum / Q000196:embryology* / Q000378:metabolism; D007797:Laminin / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008954:Models, Biological; D009024:Morphogenesis; D011509:Proteoglycans / Q000378:metabolism; D019063:Tenascin / Q000378:metabolism
chemical_list: D024042:Collagen Type I; D005353:Fibronectins; D007797:Laminin; D011509:Proteoglycans; D019063:Tenascin
keywords: Duodenojejunal flexure; Extracellular matrix; Flexure formation; Gut morphogenesis; Mouse