Low-intensity pulsed electromagnetic field stimulation enhances fusion in bovine myoblasts and improves tensile properties of engineered skeletal muscle tissue

Pulsed electromagnetic field (PEMF) stimulation has been widely investigated in musculoskeletal applications. This study investigates its application to promote bovine myoblast differentiation and maturation for cultured meat production, aiming to generate muscle constructs that better resemble conventional meat. PEMF stimulation duration and the effect of intermittent recovery were evaluated in terms of metabolic activity, differentiation markers, and structural characteristics in both 2D myoblast cultures and 3D bio-artificial muscle constructs. The best results were obtained with daily intermittent PEMF stimulation consisting of 90s stimulations separated by 30s breaks for 2h per day. This intermittent protocol increased the metabolic activity of myotubes, particularly those derived from low-fusion donors. Additionally, an increase in myoblast fusion capacity was observed under this condition. When applied to bio-artificial muscle constructs, both intermittent and 2h continuous PEMF stimulation enhanced metabolic activity, multinucleation, and striation, while maintaining similar fusion capacities to non-stimulated muscle constructs. Furthermore, PEMF-stimulated constructs exhibited significant enhancements in mechanical properties, with stiffness increasing similar to 2-fold and ultimate tensile strength rising by similar to 1.7-fold, approaching values observed in native adult muscle tissue. Concurrently, continuous stimulation led to an increase in myotube diameter. These findings suggest that low-intensity PEMF stimulation is a promising tool for muscle tissue engineering. For cultured meat applications, PEMF stimulation could improve the texture and structure of muscle constructs, thereby enhancing consumer acceptance of structured meat products.