There is a growing need to develop novel well-characterized biological inks (bioinks) that are customizable for three-dimensional (3D) bioprinting of specific tissue types. Gelatin methacryloyl (GelMA) is one such candidate bioink due to its biocompatibility and tunable mechanical properties. Currently, only low-concentration GelMA hydrogels (≤5% w/v) are suitable as cell-laden bioinks, allowing high cell viability, elongation, and migration. Yet, they offer poor printability. Herein, we optimize GelMA bioinks in terms of concentration and cross-linking time for improved skeletal muscle C2C12 cell spreading in 3D, and we augment these by adding gold nanoparticles (AuNPs) or a two-dimensional (2D) transition metal carbide (MXene nanosheets) for enhanced printability and biological properties. AuNP and MXene addition endowed GelMA with increased conductivity (up to 0.8 ± 0.07 and 0.9 ± 0.12 S/m, respectively, compared to 0.3 ± 0.06 S/m for pure GelMA). Furthermore, it resulted in an improvement of rheological properties and printability, specifically at 10 °C. Improvements in electrical and rheological properties led to enhanced differentiation of encapsulated myoblasts and allowed for printing highly viable (97%) stable constructs. Taken together, these results constitute a significant step toward fabrication of 3D conductive tissue constructs with physiological relevance.

P38 MAPKs play a central role in orchestrating the cellular response to stress and inflammation and in the regulation of myogenesis. Potent inhibitors of p38 MAPKs have been pursued as potential therapies for several disease indications due to their antiinflammatory properties, although none have been approved to date. Here, we provide a brief overview of p38 MAPKs, including their role in regulating myogenesis and their association with disease progression. Finally, we discuss targeting p38 MAPKs as a therapeutic approach for treating facioscapulohumeral muscular dystrophy and other muscular dystrophies by addressing multiple pathological mechanisms in skeletal muscle.