Embryonic stem cells improve skeletal muscle recovery after extreme atrophy in mice

Introduction We injected embryonic stem cells into mouse tibialis anterior muscles subjected to botulinum toxin injections as a model for reversible neurogenic atrophy. Methods Muscles were exposed to botulinum toxin for 4 weeks and allowed to recover for up to 6 weeks. At the onset of recovery, a single muscle injection of embryonic stem cells was administered. The myofiber cross-sectional area, single twitch force, peak tetanic force, time-to-peak force, and half-relaxation time were determined. Results Although the stem cell injection did not affect the myofiber cross-sectional area gain in recovering muscles, most functional parameters improved significantly compared with those of recovering muscles that did not receive the stem cell injection. Conclusions Muscle function recovery was accelerated by embryonic stem cell delivery in this durable neurogenic atrophy model. We conclude that stem cells should be considered a potential therapeutic tool for recovery after extreme skeletal muscle atrophy. Muscle Nerve 51: 346–352, 2015