title: Co-culture with neonatal cardiomyocytes enhances the proliferation of iPSC-derived cardiomyocytes via FAK/JNK signaling.
abstract: BACKGROUND
  We previously reported that the pluripotent stem cells can differentiate into cardiomyocytes (CMs) by co-culture with neonatal CMs (NCMs) in vitro. However, the involving mechanism is not clear.
  
  
  METHODS
  Mouse induced pluripotent stem cells (iPSCs) were cultured in hanging drops to form embryoid bodies (EBs) and to induce myocardial differentiation. Co-culture of EBs and NCMs was established in a transwell insert system, while EBs grown alone in the wells were used as controls.
  
  
  RESULTS
  Co-culture with NCMs markedly increased the generation of functional CMs from iPSCs. The focal adhesion kinase (FAK) phosphorylation, and c-Jun N-terminal kinase (JNK) phosphorylation in co-culture were higher than that in EBs grown alone. Treating FAK small interfering RNA (FAK siRNA) or specific inhibitor for JNK (SP600125) to iPSCs significantly reduced the phosphorylation of JNK and the expressions of Mef2c and Bcl-2. The expressions of cTnT and MLC-2V were also decreased. Our results revealed that co-culture with NCMs significantly enhance the differentiation ability of iPSCs by increasing Mef2c and Bcl-2 expressions concomitantly with a marked augment on cell proliferation through JNK signaling pathways.
  
  
  CONCLUSIONS
  These findings indicated that co-culture of EBs with NCMs induces genes expressed in a mature pattern and stimulates the proliferation of iPSC-derived CMs (iPS-CMs) by activating FAK/JNK signaling.
authors.affiliation: State Key Laboratory of Military Stomatology, Research and Development Center for Tissue Engineering, School of Stomatology, Fourth Military Medical University, 1st Kang-fu Road, Xi'an, 710032, Shaanxi, China.|Department of Cardiology, NO. 422 Hospital of PLA, Zhanjiang, 524005, Guangdong, China.|Department of Cardiology, Tangdu Hospital, Fourth Military Medical University, Xi'an, 710038, Shaanxi, China.
authors.forename: Dongbo
authors.initials: D
authors.lastname: Ou
authors.affiliation: Department of Cardiology, NO. 422 Hospital of PLA, Zhanjiang, 524005, Guangdong, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Cardiology, NO. 422 Hospital of PLA, Zhanjiang, 524005, Guangdong, China.
authors.forename: Yanjin
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Department of Cardiology, Tangdu Hospital, Fourth Military Medical University, Xi'an, 710038, Shaanxi, China.
authors.forename: Di
authors.initials: D
authors.lastname: Zeng
authors.affiliation: Department of Cardiology, Tangdu Hospital, Fourth Military Medical University, Xi'an, 710038, Shaanxi, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Wei
authors.affiliation: Department of Cardiology, Tangdu Hospital, Fourth Military Medical University, Xi'an, 710038, Shaanxi, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Ding
authors.affiliation: Department of Cardiology, Tangdu Hospital, Fourth Military Medical University, Xi'an, 710038, Shaanxi, China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Cardiology, Tangdu Hospital, Fourth Military Medical University, Xi'an, 710038, Shaanxi, China. tdxznk01@fmmu.edu.cn.
authors.forename: Qiangsun
authors.initials: Q
authors.lastname: Zheng
authors.affiliation: State Key Laboratory of Military Stomatology, Research and Development Center for Tissue Engineering, School of Stomatology, Fourth Military Medical University, 1st Kang-fu Road, Xi'an, 710032, Shaanxi, China. yanjin@fmmu.edu.cn.|Research and Development Center for Tissue Engineering, Fourth Military Medical University, 1st Kang-fu Road, Xi'an, 710032, Shaanxi, China. yanjin@fmmu.edu.cn.
authors.forename: Yan
authors.initials: Y
authors.lastname: Jin
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D018920:Coculture Techniques / Q000379:methods*; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000378:metabolism*; D057026:Induced Pluripotent Stem Cells / Q000166:cytology* / Q000187:drug effects; D020935:MAP Kinase Signaling System / Q000187:drug effects; D051379:Mice; D009206:Myocardium / Q000166:cytology; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology*; D009928:Organ Specificity / Q000187:drug effects; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D034741:RNA, Small Interfering / Q000378:metabolism
chemical_list: D047428:Protein Kinase Inhibitors; D034741:RNA, Small Interfering; D051416:Focal Adhesion Protein-Tyrosine Kinases
keywords: Cardiomyocytes; Co-culture; FAK/JNK; Induced pluripotent stem cells; Proliferation