Cardiac stem cells with electrical stimulation improve ischaemic heart function through regulation of connective tissue growth factor and miR-378.
OBJECTIVE
In this study, we investigated whether pre-conditioning (PC) by electrical stimulation (EleS) induces cytoprotective effect on cardiac stem cells (CSCs) and determined its underlying molecular mechanisms.


RESULTS
Sca-1(+) CSCs were isolated from male C57BL6 mice (12 weeks) hearts. PC of CSCs with EleS ((EleS)CSCs) was carried out for 3 h at 1.5 V followed by exposure to 300 µM H2O2 for 5 h. Cytoprotective effects and cell adhesion ability were significantly increased by EleS as evaluated by transferase-mediated dUTP nick-end labelling (TUNEL), lactate dehydrogenase (LDH) release assay, and adhesion assay. EleS increased phosphorylation of AKT, focal adhesion kinase (FAK), and glycogen synthase kinase (GSK3β), as well as decreased caspase-3 cleavage. Interestingly, inhibition of AKT or FAK abolished the pro-survival effects of EleS. We found that connective tissue growth factor (Ctgf) was responsible for EleS-induced CSC survival and adhesion.The survival rate of (EleS)CSCs after transplantation in the infarcted myocardium was significantly increased together with improvement in cardiac function. Importantly, knockdown of Ctgf abolished EleS-induced cytoprotective effects and recovery of cardiac function. Furthermore, we identified miR-378 as a potential Ctgf regulator in (EleS)CSCs.


CONCLUSIONS
EleS enhanced CSC survival in vitro and in vivo as well as functional recovery of the ischaemic heart through an AKT/FAK/CTGF signalling pathway. It is suggested that Ctgf and miR-378 are novel therapeutic targets for stem cell-based therapy.
Department of Molecular and Cellular Physiology.
Sun Wook
SW
Kim
Ha Won
HW
Kim
Wei
W
Huang
Motoi
M
Okada
Jeffrey A
JA
Welge
Yigang
Y
Wang
Muhammad
M
Ashraf
D000818:Animals; D000950:Antigens, Ly / Q000032:analysis; D002448:Cell Adhesion; D002470:Cell Survival; D055513:Connective Tissue Growth Factor / Q000502:physiology*; D019610:Cytoprotection; D004599:Electric Stimulation Therapy; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000502:physiology; D008565:Membrane Proteins / Q000032:analysis; D051379:Mice; D008810:Mice, Inbred C57BL; D035683:MicroRNAs / Q000502:physiology*; D017202:Myocardial Ischemia / Q000503:physiopathology / Q000628:therapy*; D032383:Myocytes, Cardiac / Q000502:physiology*; D018384:Oxidative Stress; D051057:Proto-Oncogene Proteins c-akt / Q000502:physiology; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000502:physiology
D000950:Antigens, Ly; C074650:Ly6a protein, mouse; C546119:MIRN378 microRNA, mouse; D008565:Membrane Proteins; D035683:MicroRNAs; D055513:Connective Tissue Growth Factor; D051416:Focal Adhesion Protein-Tyrosine Kinases; D051057:Proto-Oncogene Proteins c-akt
CTGF; Electrical stimulation; Ischaemic heart; Survival; miR-378