Biomimetic Conductive Hydrogel Scaffolds with Anisotropy And Electrical Stimulation for in Vivo Skeletal Muscle Reconstruction.

The nature of the hydrogel scaffold mimicking extracellular matrix plays a crucial role in tissue engineering like skeletal muscle repair. Herein, an anisotropic and conductive hydrogel scaffold was fabricated using GelMA as the matrix hydrogel and AgNW as the conductive dopant, through a directional freezing technique for muscle defect repair. The scaffold has an anisotropic structure composed of a directional longitudinal section and a honeycomb cross-section, with high mechanical strength of 10.5 kPa and excellent conductivity of 0.26 S/m. These properties are similar to native muscle ECM and allow for cell orientation under the guidance of contact cues and electrical stimulation synergistically. In vitro experiments have shown that the scaffold's oriented structure combined with electrical stimulation results in enhanced myotube formation, with a length of up to 863 μm and an orientation rate of 81%. Furthermore, the electrically stimulated scaffold displays a promoted muscle reconstruction ability when transplanted into rats with muscle defects, achieving a muscle mass and strength restoration ratio of 95% and 99%, respectively, compared to normal levels. These findings suggest that the scaffold has great potential in muscle repair applications. This article is protected by copyright. All rights reserved.