Vascularized Silk Electrospun Fiber For Promoting Oral Mucosa

Objective:Construct the fibrous membrane capable of promoting angiogenesis via loading leptin onto silk fibroin fiber and study the ability of fibrous membrane to promote the oral mucosa regeneration.Methods:Silk fiber was prepared by electrospinning technology and leptin liposomes were prepared by film dispersion method.The surface of liposomes was aminated and grafted on the surface of silk fiber using through polydopamine as bridge to build vascularizable fibrous membrane.TEM、SEM、and AFM were used to characterized the morphology of liposomes and fibers.WCA and mechanical tester characterize the physical and chemical properties of the fiber membrane.Rat fibroblasts were planted on the fibrous membrane,and the cytotoxic effect of the fibers on the cells was examined by CCK-8 method and cell fluorescent staining.HUVECs were cultured with fibrous membrane extract to investigate the ability of fibrous ability of angiogenesis.Rabbit oral mucosal defect model was constructed to evaluate the fiber capability to promote mucosal regeneration.Results:After the silk fibroin was modified with polydopamine and liposomes grafted,the morphology changed slightly,but the hydrophilicity and mechanical properties were obviously improved.After co-culture of fibers and fibroblasts,it was found that the fiber membrane had no significant effect on cell proliferation and morphology.In vitro tube formation experiments found that HUVECs differentiated and arranged into obvious network structure after 5 hours of leptin-loaded fiber extract.In the rabbit oral mucosa large-area defect model,the rate of wound closure was higher in leptin-loaded fiber treatment than in the other groups,and the signal of CD34 under the regenerated mucosa was the most obvious.Conclusion:After leptin-encapsulated liposomes was grafted onto the surface of silk fiber via polydopamine,although the surface roughness of the fiber was increased,the mechanical properties and hydrophilicity of the fiber were improved.Leptin-loaded silk fiber had good cell compatibility.Leptin released by liposomes can effectively promote vascular regeneration and increase the rate of oral mucosal defects closure.