Synergistic effect of miR-9 overexpression and electrical induction on differentiation of conjunctiva mesenchymal stem cells into photoreceptor-like cells.

A variety of genes and materials can induce the differentiation of stem cells. The purpose of this work was to investigate the effect of microRNA-9 (miR-9) overexpression and electrical induction on the photoreceptor differentiation of Conjunctiva Mesenchymal Stem Cells (CJMSCs). In this study, an electroconductive scaffold (silk fibroin polymer (SF) and reduced graphene oxide (rGo) nanoparticles) was fabricated by electrospinning method, and its characteristics such as diameter, graphene distribution, compound, conductivity, and toxicity were evaluated by scanning and transmission electron microscopy (SEM and TEM), FTIR, electrochemical impedance spectroscopy, and MTT assay. The cells were transduced by a lentiviral vector carrying miR-9, then electrical induction was implied on mir-9-CJMSCs, cultivated on the fabricated scaffold, and the expressions of neural and photoreceptor marker genes were evaluated by RT-qPCR. A uniform, smooth appearance with lower diameter, uniform distribution of rGo nanoparticles across the fibers, and lower resistance were shown in SF-rGo fibrous scaffold. After electrical stimulation, lower and higher expression of neural marker genes and photoreceptor marker genes (Rhodopsin, PKC) were documented, respectively. Finally, we proposed that the combinational approach of miR-9 overexpression and electrical induction leads CJMSCs to photoreceptor-like cells.