Glucosamine/collagen assembled biomimetic nanofibrous mats via LBL deposition for cartilage engineering

In order to highly simulate the chondrocyte extracellular matrix, electrospinning and layer-by-layer (LBL) self-assembly techniques were applied in this study. Polycaprolactone (PCL) with good mechanical property was selected as the substrate, while D-glucosamine sulfate (GAS) and collagen type I (COL) with chondroprotective properties were coated on the surfaces of PCL nanofibers. The morphology, chemical and physical investigations suggested the successful deposition of GAS/COL, improved mechanical properties and significantly ameliorated surfaces hydrophilicity after LBL medication. The release of GAS/COL was proved to be slow and sustainable. Besides, CCK-8 assay and cell morphology observation manifested that LBL structured mats were more suitable for rat articular chondrocytes (rACs) adhesion and proliferation, while quantitative Real-Time polymerase chain reaction analysis and glycosaminoglycans (GAG) production measurement indicated the introduction of GAS/COL upregulated glucuronosyltransferase I (GlcAT-I) gene expression and GAG content in rACs. Additionally, LBL structured mats induced GlcAT-I expression and reduced interleukin‐1β (IL‐1β) and Matrix metalloproteinases 13 (MMP13) expression in IL‐1β-induced rACs. Moreover, subcutaneous model in SCID mice further confirmed that GAS/COL modified PCL mat could facilitate the GAG production and collagen type II expression of rACs.