Physically crosslinked poly(vinyl alcohol)-based hydrogels for cartilage tissue engineering

Due to the limited self-healing ability of cartilage, cartilage defect repair remains a challenge in clinical treatment. Therefore, there is a need to provide patients with a promising cartilage defect repair strategy. In this study, we have reported an icariin-loaded PVA based biocompatible hydrogel scaffold for cartilage defect repair. The PTGH + Icariin hydrogel was prepared by a simple physical cross-linking method and consists of polyvinyl alcohol (PVA), tannic acid (TA), gelatin (Gel), hyaluronic acid (HA) and icariin. Inspired by the natural cartilage matrix compositions, the Gel and HA were used to improve the bioactivity and biocompatibility of hydrogel. Furthermore, icariin was introduced to further enhance the hydrogel's ability for cartilage regeneration. The results showed that PTGH + icariin hydrogel exhibited porous microstructures and tough mechanical properties. In vitro cell experiments confirmed PTGH + Icariin hydrogels could promote chondrocytes proliferation, chondrocytes spreading and chondrocytes migration. Meanwhile, the PTGH + Icariin hydrogel demonstrated the ability to promote the cartilage regeneration in a rat cartilage defect model. In particular, the implantation of PTGH + Icariin hydrogel could facilitate the restoration of motor function in rats. This study will provide a potential approach for the treatment of cartilage defects.