Effect of different electrical stimulation waves on orientation and alignment of adipose derived mesenchymal stem cells

To investigate the effect of different electrical stimulation waves on orientation and alignment of adipose derived mesenchymal stem cells (ADSCs). ADSCs were isolated from 5-week-old Sprague Dawley rats (weight, 100-150 g) and cultivated. The cells at passages 3-5 were inoculated to prepare cell climbing slices, subsequently was exposed to direct-current electrical stimulations (ES) at electric field strengths of 1, 2, 3, 4, 5, and 6 V/cm on a homemade electric field bioreactor (groups A1, A2, A3, A4, A5, and A6); at electric field strength of 6 V/cm, at 50% duty cycle, and at frequency of 1 and 2 Hz (groups B1 and B2) of square wave ES; at electric field strength of 6 V/cm, at pulse width of 2 ms, and at frequency of 1 and 2 Hz (groups C1 and C2) of biphasic pulse wave ES; and no ES was given as a control (group D). The changes of cellular morphology affected by applied ES were evaluated by time-lapse micropho-tography via inverted microscope. The cell alignment was evaluated via average orientation factor