Sulfated chitosan coated polylactide membrane enhanced osteogenic and vascularization differentiation in MC3T3-E1s and HUVECs co-cultures system.

This study aimed to compare the effects of the two type chitosan derivatives, sulfated chitosan (SCS) and phosphorylated chitosan (PCS), coated on poly(d,l-lactide) (PDLLA) membrane via polydopamine, respectively, on vascularization and osteogenesis in vitro. Mouse preosteoblast cells (MC3T3-E1s) and human umbilical vein endothelial cells (HUVECs) were used as co-cultures system. The effects of two type membranes on calcium deposition, alkaline phosphatase (ALP) activity, vascularization related factors nitric oxide (NO) and angiogenic growth factor vascular endothelial growth factor (VEGF) were assessed. The changes of osteogenic and angiogenic related gene, and protein expression were evaluated too. In fact, SCS modified PDLLA membrane had the highest related gene and protein expression than other PDLLA membranes. Our results demonstrated that the SCS maybe a promising matrix for bone regeneration by co-cultures of ECs and OCs than PCS.

Different influence of sulfated chitosan with different sulfonic acid group sites on HUVECs behaviors.

The vascularization within the scaffold is still a significant challenge in tissue engineering applications. Sulfated chitosan (SCS) as an amazing substance have been used in tissue engineering to stimulate angiogenesis. However, it is not clear whether they have difference in the ability to promote vascularization of SCS with different sulfonic acid group sites. The aim of this study was to evaluate human umbilical vein endothelial cells (HUVECs) viability and differentiation in vitro, affected by three types of sulfated chitosan' i.e. 2-N-6-O-sulfated chitosan (2,6-SCS), 3'6-O-sulfated chitosan (3,6-SCS) and 6-O-sulfated chitosan (6-SCS). The results are showed that all the SCS possesses excellent biological properties to promote HUVECs viability and proliferation. Especially, 2,6-SCS promotes desirable intracellular nitric oxide secretion and capillary tube formation. Meanwhile, 2,6-SCS up-regulate the related gene and protein expression compared with other sulfonic acid group sites SCS and heparin. Therefore, 2,6-SCS is a promising substitute material for angiogenesis and as aqueous formulation can be employed to fabrication functionalization scaffold surface with promoted angiogenesis.

Sulfonated chitosan and phosphorylated chitosan coated polylactide membrane by polydopamine-assisting for the growth and osteogenic differentiation of MC3T3-E1s.

In this study, a poly(d,l-lactide) (PDLLA) membrane was prepared by the solution casting method, then the surface of the membrane was modified by polydopamine (PDOPA) as a substrate, followed by adsorption of different chitosan derivative sulfonated chitosan (SCS) or/and phosphorylated chitosan (PCS) to obtain different functionalized membranes, and two kinds of chitosan derivatives characterized by FTIR, elemental analysis and zeta potential. And different membranes were evaluated through surface potential, hydrophilicity, surface morphology and chemical compositions. In vitro, the cell culture results showed that the membrane functionalized by chitosan derivative could promote the proliferation of MC3T3-E1s and enhance the osteogenic differentiation by up-regulating the expression level of osteogenic genes compared to the PDLLA and P1/PDOPA membranes. Especially, when the outermost layer was SCS, the effect of promoting cell proliferation was better than that of PCS. However, for osteogenic differentiation, PCS had better quantitative experimental results than SCS. Therefore, SCS has superiority in promoting proliferation than PCS, but PCS is opposite in promoting osteogenic differentiation for MC3T3-E1s. The results suggested that PCS and SCS have the potential value to be used as a functional modified materials applied in bone tissue engineering.