Engineering a mucin coating to promote osteogenic differentiation of BMSCs in vitro and bone formation in vivo through the Wnt/-catenin pathway

Mucin, a family of glycoproteins, is widespread in the inner linings of various lumen organs and plays key roles in protecting epithelial cells from invasion by foreign species and communicating with the external environment. Here, we demonstrated that Mucin could be engineered as a promising building block in biomaterials with unexpected multifunctionalities by codepositing with procyanidin (PC, a kind of flavanol polyphenol) through a layer-by-layer technique. The process of generating PC/Mucin multilayers was well characterized and monitored, which was controllable by the assembly conditions. The behaviors of bone marrow mesenchymal stem cells (BMSCs), including proliferation, antioxidant ability, and expression of vinculin, were investigated to reveal the role of PC/Mucin multilayers on the osteogenic differentiation of BMSCs. Our data showed that PC/Mucin multilayers promoted osteogenesis-related genes (Col1, ON, OCN and RUNX2) in BMSCs in vitro and bone generation in vivo by activating the Wnt/beta-catenin pathway. These findings demonstrate that engineering Mucin might be a new route in the future to implant materials or coatings for bone regeneration.