Skin-permeable liposome improved stability and permeability of bFGF against skin of mice with deep second degree scald to promote hair follicle neogenesis through inhibition of scar formation

Excessive deposition of extracellular matrix (ECM) usually resulted in scar formation during wound healing, which caused skin dysfunction, such as hair loss. Basic fibroblast growth factor (bFGF) was very helpful for promoting hair follicle neogenesis and regulating the remodeling of ECM during wound healing. Because of its poor stability in wound fluids and low permeability against the dense wound scar, the repairing quality of bFGF on wound was hindered largely in clinical practice. To overcome these drawbacks, herein, a novel liposome with silk fibroin hydrogel core (bFGF-SF-LIP) was firstly prepared to stabilize bFGF, followed by insertion of laurocapam, a permeation enhancer, into the liposomal membrane to construct a skin-permeable liposome (SP-bFGF-SF-LIP). The encapsulated efficiency of bFGF was reaching to nearly 90% when ratio of drug/lipids above 1:300, and it activity was not compromised by laurocapam. SP-bFGF-SF-LIP exhibited a hydrodynamic diameter of 103.3 nm and Zeta potential of -2.31 mV. The stability of the encapsulated bFGF in wound fluid was obviously enhanced. After 24 h of incubation with wound fluid containing MMP-9, the remaining bFGF was as high as 65.4 +/- 0.5% for SP-bFGF-SF-LIP, while only 2.1 +/- 0.2% of free bFGF was remained. The skin-permeability of bFGF was significantly enhanced by SP-bFGF-SF-LIP and most of the encapsulated bFGF penetrated into the dermis. After treatment with SP-bFGF-SF-LIP, the morphology of hair follicle at wound zone was obviously improved and the hair regrew on the deep second scald mice model. The therapeutic mechanism was highly associated with inhibiting scar formation and promoting vascular growth in dermis. Conclusively, SP-bFGF-SF-LIP may a potential option to improve wound healing with high-quality.