Organic photovoltaic device enhances the neural differentiation of rat bone marrow-derived mesenchymal stem cells

Electrical stimulation is known to be involved in stem cell differentiation,particularly neural differentiation.Various electrical stimulation systems and devices have been developed for neural tissue engineering.The organic photovoltaic materials PM6 and Y6 have showed high-power conversion efficiency.In this study,we used PM6 and Y6 to develop an organic photovoltaic device(OPD)to supply electrical stimulation.The photoelectric stimulation by the OPD showed no impact on cell viability.We tested the neural differentiation potential of rat bone marrow-derived mesenchymal stem cells(rBMSCs)under light induced electrical stimulation.The changes in cell morphology suggested that photoelectric stimulation significantly increased the neurite length and the number of extremities of differentiated neural cells.In addition,genes of neuron markers and neurotrophic factors were upregulated when rBMSCs were under photoelectric stimulation.Furthermore,the calcium influx of differentiated cells responding to acetylcholine and the phosphorylation of extracellular-signal-regulated kinase(ERK)1 and 2,protein kinase B(AKT)and mammalian target of rapamycin(mTOR)were significantly elevated after photoelectric stimulation.These findings demonstrated that PM6:Y6 based OPD could provide photoelectric stimulation to enhance rBMSCs neural differentiation,which might be an alternative approach to electrically manipulate stem cells differentiation into neural cells in vitro.