Iranian Journal of Basic Medical Sciences

Iranian Journal of Basic Medical Sciences

Generation of oligodendrocyte precursor-like cells from mouse embryonic fibroblasts using miR-7a mimics

Articles in Press

Document Type : Original Article

Authors
Maryam Ghasemi-Kasman 1, 2
Maryam Nakhaei-Nejad 3
Fatemeh Rabiei 4
Fabrizio Giuliani 3
1 Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
2 Department of Physiology, Faculty of Medicine, Babol University of Medical Sciences, Babol, Iran
3 Department of Medicine, University of Alberta, Edmonton, Canada
4 Student Research Committee, Babol University of Medical Sciences, Babol, Iran
10.22038/ijbms.2026.96127.20729
Abstract
Objective(s): Developing effective strategies to enhance remyelination remains a major therapeutic challenge in demyelinating disorders such as multiple sclerosis (MS). MicroRNAs (miRNAs) have emerged as powerful regulators of cell fate. It has been shown that miR-7a is highly expressed in oligodendrocyte precursor cells (OPCs). This study aimed to investigate whether overexpression of miR-7a can reprogram mouse embryonic fibroblasts (MEFs) into OPC-like cells and oligodendrocytes in vitro.
Materials and Methods: MEFs were cultured, confirmed by vimentin immunostaining, and transfected with miR-7a mimics using LipofectamineTM 3000 or LipofectamineTM RNAiMAX reagent. Transfection efficiency was assessed by qRT-PCR analysis of miR-7a expression levels. Cells were then cultured in OPC induction medium and assessed for NG2 expression at 14 and 21 days post-transfection. Differentiation potential was examined by transferring induced cells into oligodendrocyte differentiation medium and analyzing O4 and MBP expression using Immunocytofluorescence.
Results: LipofectamineTM RNAiMAX-mediated transfection produced significantly higher miR-7a expression than LipofectamineTM 3000, with a clear dose-dependent effect. MEFs transfected with miR-7a (10 and 20 pmol) exhibited NG2-positive cells at both 14 and 21 days, whereas no OPC markers were observed in negative controls or induction medium alone. Furthermore, miR-7a-induced OPC-like cells differentiated into O4⁺ and MBP⁺ oligodendrocytes, confirming their lineage potential.
Conclusion: Overexpression of miR-7a successfully reprogrammed MEFs into OPC-like cells and promoted their differentiation into oligodendrocytes in vitro. These findings establish miR-7a as a potential tool for cell-based reprogramming strategies to generate OPC-like cells, warranting further investigation before translation into in vivo remyelination procedures for MS.
Keywords
Cellular reprogramming techniques
Fibroblasts
MicroRNAs
MiR-7a
Multiple sclerosis
Oligodendrocyte precursor cells
Subjects
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Iranian Journal of Basic Medical Sciences

Articles in Press, Accepted Manuscript
Available Online from 11 August 2026