A new study found that Duchenne muscular dystrophy (DMD) muscle cells had altered (more positive) resting membrane potential (RMP) and reduced muscle membrane resistance compared to healthy muscle cells.
The study authors concluded, “DMD skeletal muscle cells are more depolarized, and that membrane integrity is compromised in DMD cells when compared to healthy muscle cells.”
In addition, they observed an improvement in RMP after incubating DMD muscle cells in 1% poloxamer 188 (P188) for 1 hour. The effect was further enhanced using longer incubation times. Therefore, P188 treatment may improve DMD muscle cells’ physiology.
P188 is an amphiphilic block copolymer that has been shown to stabilize the plasma membrane and enhance membrane integrity, thereby protecting dystrophic muscles from mechanical stress.
To evaluate DMD electrophysiology, Nguyen et al generated 3-dimensional bioengineered skeletal muscle tissues using immortalized DMD myoblast cell lines (DMD5-13515 and KM571-DMD).
“Our characterization will form a baseline for further studies directed at skeletal muscle function and serve to establish 3D muscle culture as a preclinical platform to test the efficacy of promising candidate therapies for muscle disease,” the authors wrote.
Nguyen CT, Ebrahimi M, Gilbert PM, Stewart BA. Electrophysiological analysis of healthy and dystrophic 3D bioengineered skeletal muscle tissues. Am J Physiol Cell Physiol. Published online August 18, 2021. doi:10.1152/ajpcell.00049.2021