Chitosan-gelatin sheets as scaffolds for muscle tissue engineering

Hydrogels made of natural polymers [chitosan (CS) and gelatin (G)] have been prepared having mechanical properties similar to those of muscle tissues. In this study, the effect of polymer concentration and scaffold stiffness on the behavior of seeded muscle-derived cells (MDCs) on the CS-G hydrogel sheets has been evaluated. Both variables were found to be important in cell viability. Viability was assessed by observation of the cell morphology after 1 day as well as a 14-day MTT assay. The CS-G hydrogels were characterized using Fourier transform infrared (FTIR) analysis, which revealed evidences of strong intermolecular interactions between CS and G. Hydrogel samples with intermediate concentration of CS had suitable handling characteristics for surgical purposes as well as similar elasticity to muscle tissues. The sample with intermediate stiffness (22 +/- 1kPa) exhibited the greatest attachment, expansion, and proliferation rate. Such CS-G hydrogels with intermediate stiffness may be considered as new candidates for muscle tissue engineering in the reconstructive field of urology.