title: [Biphasic pulsed electrical stimulation promotes the differentiation of adipose-derived stem cells into cardiomyocyte-like cells].
abstract: OBJECTIVE
  To design a biphasic pulsed electrical stimulation (BPES) system for cardiac tissue engineering and investigate the effect of BPES on the cardiomyocyte-like differentiation of adipose-derived stem cells (ADSCs) in vitro.
  
  
  METHODS
  ADSCs were isolated and cultivated from Sprague Dawley rats. Surface protein expression was detected by flow cytometry to identify the cell phenotype. The multi-differentiation potential of ADSCs was verified by adipogenic and osteogenic inducers. The cells of the third passage were randomly divided into 2 groups: BPES group was subjected to BPES 24 hours after the cells were plated in 6-well culture plates, and BPES was set as 2 ms square pulses delivered at 2 Hz, 2 V voltage amplitude, and lasted 2 hours per day, for 3, 4 or 7 days. The culture medium was replaced every 3 days. Control group was cultured with the same condition but without BPES. The cell morphology was observed under an inverted phase-contrast microscope. Cell proliferation was evaluated by the MTT assay. The expression of cardiac-specific homeobox Nkx-2.5 and connexin 43(CX43) was determined by immunofluorescence cytochemistry.
  
  
  RESULTS
  The flow cytometry proved that the isolated cells were ADSCs. Oil red O staining showed the fat droplets in the cytoplasm of ADSCs after adipogenic induction. alkaline phosphatase and Von Kossa staining showed calcium nodes in the ADSCs after osteogenic induction. No obvious changes were found in the proliferation of ADSCs. The levels of Nkx-2.5 and CX43 proteins were significantly higher in the BPES group than in the control group.
  
  
  CONCLUSIONS
  BPES system we designed for tissue engineering could promote the differentiation of ADSCs into cardiomyocyte-like cells in vitro.
authors.affiliation: Department of Medical Information Engineering, School of Electrical Engineering and Information, Sichuan University, Chengdu 610065, China.
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Medical Information Engineering, School of Electrical Engineering and Information, Sichuan University, Chengdu 610065, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Yang
authors.affiliation: Department of Medical Information Engineering, School of Electrical Engineering and Information, Sichuan University, Chengdu 610065, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Huang
authors.affiliation: Department of Cardiovascular Surgery, West China School of Clinical Medicine, Sichuan University, Chengdu 610041, China.
authors.forename: Zhenghua
authors.initials: Z
authors.lastname: Xiao
authors.affiliation: Department of Medical Information Engineering, School of Electrical Engineering and Information, Sichuan University, Chengdu 610065, China.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Ren
mesh_terms: D000273:Adipose Tissue / Q000166:cytology*; D000818:Animals; D002454:Cell Differentiation; D049109:Cell Proliferation; D018031:Connexin 43 / Q000032:analysis; D004558:Electric Stimulation; D005260:Female; D032383:Myocytes, Cardiac / Q000166:cytology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013234:Stem Cells / Q000166:cytology*
chemical_list: D018031:Connexin 43; C580592:Gja1 protein, rat