A physically cross-linked double network polysaccharides/Ca2+ hydrogel scaffold for skeletal muscle tissue engineering

Abstract

The current therapy for muscle injury is facing challenges in tissue self-regeneration and function restoration, which declines steeply with age. Tissue engineering is a promising strategy for treating skeletal muscular disorders. Natural polysaccharides have great potential to support cell growth and attachment as tissue-engineered scaffolds. A three-dimensional (3D) porous hydrogel scaffold has been prepared based on the double network of natural polysaccharide sodium alginate (SA), chitosan (CS) and Ca2+ ions through the freeze-drying process. The physical, mechanical, and biological properties of the CS/SA/Ca2+ hydrogel scaffold can be controlled by adjusting the SA/CS ratio. The physically cross-linked double network hydrogel showed good biosafety, high stability and satisfactory degradation rate. When the CS/SA molar ratio was 1:1.2 (H-1.2 group), the pore size and compression modulus of the double network hydrogel were 104.06 ± 2.64 µm and 40.00 ± 2.52 kPa, respectively. The results of in vitro evaluation showed that the 3D structure of the CS/SA/Ca2+ double network hydrogel could well support adhesion and proliferation of C2C12 murine myoblasts and porcine skeletal muscle stem cells. The best cell growth effect was achieved in the H-1.2 group. The physically cross-linked CS/SA/Ca2+ double network hydrogel can be a promising printable material as the cell scaffold in applications of skeletal muscle tissue engineering.