Reprogramming efficiency and quality of induced Pluripotent Stem Cells (iPSCs) generated from muscle-derived fibroblasts of mdx mice at different ages

Induced pluripotent stem cells (iPSCs) hold promise as a potential treatment for Duchenne muscular dystrophy (DMD). To determine the impact of the donor's age on reprogramming, we generated iPSCs from muscle-derived fibroblasts (MuFs) of mdx mice aged 6 weeks, 6 months, and 14 months. MuFs from 14-month-old mdx mice showed lower proliferative activity and lower reprogramming efficiency, compared with those from younger mdx mice. Furthermore, iPSCs derived from 14-month-old mdx mice (14m-MuF-iPSCs) gradually lost Nanog expression, and regressed in conventional ES medium during passages. Interestingly, inhibition of TGF-β signaling and BMP signaling stabilized Nanog expression and promoted self-renewal of 14m-MuF-iPSCs. Finally, rescued mdx-derived iPSCs efficiently differentiated into the skeletal muscle lineage.