title: The spatiotemporal development of intercalated disk in three-dimensional engineered heart tissues based on collagen/matrigel matrix.
abstract: Intercalated disk (ID), which electromechanically couples cardiomyocytes into a functional syncitium, is closely related to normal morphology and function of engineered heart tissues (EHTs), but the development mode of ID in the three-dimensional (3D) EHTs is still unclear. In this study, we focused on the spatiotemporal development of the ID in the EHTs constructed by mixing neonatal rat cardiomyocytes with collagen/Matrigel, and investigated the effect of 3D microenvironment provided by collagen/Matrigel matrix on the formation of ID. By histological and immmunofluorescent staining, the spatiotemporal distribution of ID-related junctions was detected. Furthermore, the ultra-structures of the ID in different developmental stages were observed under transmission electron microscope. In addition, the expression of the related proteins was quantitatively analyzed. The results indicate that accompanying the re-organization of cardiomyocytes in collagen/Matrigel matrix, the proteins of adherens junctions, desmosomes and gap junctions redistributed from diffused distribution to intercellular regions to form an integrated ID. The adherens junction and desmosome which are related with mechanical connection appeared earlier than gap junction which is essential for electrochemical coupling. These findings suggest that the 3D microenvironment based on collagen/Matrigel matrix could support the ordered assembly of the ID in EHTs and have implications for comprehending the ordered and coordinated development of ID during the functional organization of EHTs.
authors.affiliation: Department of Advanced Interdisciplinary Studies, Institute of Basic Medical Sciences and Tissue Engineering Research Center, Academy of Military Medical Sciences, Beijing, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Zhou
authors.forename: Yao
authors.initials: Y
authors.lastname: Shu
authors.forename: Shuang-Hong
authors.initials: SH
authors.lastname: Lü
authors.forename: Jun-Jie
authors.initials: JJ
authors.lastname: Li
authors.forename: Hong-Yu
authors.initials: HY
authors.lastname: Sun
authors.forename: Rong-Yu
authors.initials: RY
authors.lastname: Tang
authors.forename: Cui-Mi
authors.initials: CM
authors.lastname: Duan
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Qiu-Xia
authors.initials: QX
authors.lastname: Lin
authors.forename: Yong-Chao
authors.initials: YC
authors.lastname: Mou
authors.forename: Xia
authors.initials: X
authors.lastname: Li
authors.forename: Chang-Yong
authors.initials: CY
authors.lastname: Wang
mesh_terms: D022005:Adherens Junctions / Q000378:metabolism / Q000648:ultrastructure; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D015820:Cadherins / Q000378:metabolism; D060833:Cellular Microenvironment; D003094:Collagen / Q000737:chemistry*; D018031:Connexin 43 / Q000378:metabolism; D003896:Desmosomes / Q000378:metabolism / Q000648:ultrastructure; D004338:Drug Combinations; D017629:Gap Junctions / Q000378:metabolism / Q000648:ultrastructure; D006321:Heart / Q000033:anatomy & histology / Q000502:physiology; D007797:Laminin / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000378:metabolism; D051191:Plakophilins / Q000378:metabolism; D011509:Proteoglycans / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D023822:Tissue Engineering; D054457:Tissue Scaffolds
chemical_list: D015415:Biomarkers; D015820:Cadherins; C489083:Cdh2 protein, mouse; D018031:Connexin 43; D004338:Drug Combinations; D007797:Laminin; C495338:Pkp2 protein, mouse; D051191:Plakophilins; D011509:Proteoglycans; C059485:matrigel; D003094:Collagen