Construction of an acellular spinal cord scaffold with a novel NT-3 sustained-release system promotes the neural differentiation of BMSCs through the NT-3/TrkC pathway

In previous neural tissue engineering studies, we successfully constructed NT-3 cross-linked acellular spinal cord scaffolds (NT-3 cross-linked scaffolds), which can sustain the release of NT-3 and promote the differentiation of rat bone marrow mesenchymal stem cells (BMSCs) into neuron-like cells. However, the molecular mechanism by which NT-3 cross-linked scaffolds promote BMSC differentiation into neurons is unknown, coupled with the low drug loading of scaffolds and the sudden release of NT-3 on the first day. We used WB and PCR in combination with NT-3/TrkC, MAPK/ERK, and PI3K/Akt pathway inhibitors to determine the mechanism of action in vitro. We hypothesized that NT-3 mediates the NT-3/TrkC pathway as a major target molecule that promotes the differentiation of BMSCs into neurons. We prepared an improved NT-3 scaffold and improve the sustained release of NT-3 through the combination of heparin methacryloyl and EDC/NHS. The adhesion, proliferation, differentiation, and NT-3/TrkC signaling pathway of BMSCs on different scaffolds were analyzed. We concluded that NT-3-improved scaffolds can be loaded with more NT-3 and more effectively promote the differentiation of BMSCs into neurons through the NT-3/TrkC pathway. The proposed method has biocompatibility and provides a new idea for spinal cord repair.