Effects of cholesterol-bearing pullulan (CHP)-nanogels in combination with prostaglandin E1 on wound healing

The cholesterol-bearing pullulan (CHP)-nanogels are able to trap hydrophobic drugs or proteins inside the nanogels, which is potential in application to drug delivery system and tissue engineering. On the other hand, prostaglandin E1 (PGE1) plays important roles in wound healing and PGE1 ointment has been clinically used to treat chronic skin ulcers and wounds. The purpose of this study is to evaluate effects of CHP nanogels in combination with prostaglandin E1 on wound healing in full thickness skin defect model. A square skin defect (1 x 1 cm(2)) of full thickness was created on the dorsal of Wistar rats. The wound was treated with CHP nanogels without PGE1 (CHP group) or CHP nanogels containing with PGE1 (CHP/PGE1 group) or PGE1 ointment (PGE1 ointment group). In both CHP/PGE1 and PGE1 ointment groups, approximately 6 microg of PGE1 was applied to each wound. In the control group, the wound was untreated. The wound was evaluated in measuring wound area and histologically. In CHP/PGE1 group, the rate of wound size reduction was significantly higher than the ones of other groups. Histologically, CHP/PGE1 promoted neoepithelialization, neovascularization, and wound closure compared to the other treatments. These results suggest that CHP in combination with PGE1 can promote wound healing, which confirms the efficiency of CHP nanogels-based drug delivery system.