title: Efficient cardiomyocyte differentiation of embryonic stem cells by bone morphogenetic protein-2 combined with visceral endoderm-like cells.
abstract: As the signals required for cardiomyocyte differentiation and functional regulation are complex and only partly understood, the mechanisms prompting the differentiation and specification of pluripotential embryonic stem (ES) cells into cardiomyocytes remain unclear. We hypothesized that a combined technology system, cocultured with a visceral endoderm (VE) - like cell line, END-2, and added cytokine BMP-2, would induce high percentage conversion of murine ES-D3 cell line into cardiomyocytes, and derived cardiomyocytes in this system would exhibit more mature characteristics. It was observed that 92% (P<0.01) ES cell-derived aggregates in this system exhibited rhythmic contractions, and the contractile areas were greater. By contrast, in ES cells cultured alone, on the feeder layer of END-2 cells, or with added BMP-2, the total percentage of beating aggregates was 19, 69 (P<0.01) and 44% (P<0.01), respectively. All the rhythmically contractile cells derived from ES cells expressed cardiac-specific proteins for troponin T. Among them, the combined system resulted in significantly increased cardiac-specific genes (NKx2.5, alpha-MHC). Transmission electron microscopy (TEM) revealed varying degrees of myofibrillar organization, and the combined system resulted in a more mature phenotype such as Z bands, nascent intercalated discs and gap junctions. Before shifting to the cardiomyocyte phenotype, this system could accelerate apoptosis of the cell population (P<0.01). The inductive efficacy of this system can provide an opportunity to facilitate cardiomyocyte differentiation of ES cells. The inducible effects of this system may depend on increasing cardiac-specific gene expression and the induction of apoptosis in cells that are not committed to cardiac differentiation.
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, China. zengbin19982005@yahoo.com.cn
authors.forename: Zeng
authors.initials: Z
authors.lastname: Bin
authors.forename: Lin-Guo
authors.initials: LG
authors.lastname: Sheng
authors.forename: Zhu-Chen
authors.initials: ZC
authors.lastname: Gang
authors.forename: Jiang
authors.initials: J
authors.lastname: Hong
authors.forename: Cai
authors.initials: C
authors.lastname: Jun
authors.forename: Yang
authors.initials: Y
authors.lastname: Bo
authors.forename: Shen
authors.initials: S
authors.lastname: Hui
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects*; D002478:Cells, Cultured; D018920:Coculture Techniques / Q000379:methods; D004627:Embryonic Induction / Q000187:drug effects; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000187:drug effects; D004707:Endoderm / Q000166:cytology; D051379:Mice; D046529:Microscopy, Electron, Transmission; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D014781:Viscera / Q000166:cytology
chemical_list: C525719:Bmp2 protein, mouse; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D016212:Transforming Growth Factor beta