Bioactive Insulin-Loaded Electrospun Wound Dressings for Localized Drug Delivery and Stimulation of Protein Expression Associated with Wound Healing.

Effective therapy of wounds is difficult, especially for chronic, non-healing wounds, and novel therapeutics are urgently needed. This challenge can be addressed with bioactive wound dressings providing a microenvironment and facilitating cell proliferation and migration, ideally incorporating actives, which initiate and/or progress effective healing upon release. In this context, electrospun scaffolds loaded with growth factors emerged as promising wound dressings due to their biocompatibility, similarity to the extracellular matrix, and potential for controlled drug release. In this study, electrospun core-shell fibers were designed composed of a combination of polycaprolactone and polyethylene oxide. Insulin, a proteohormone with growth factor characteristics, was successfully incorporated into the core and was released in a controlled manner. The fibers exhibited favorable mechanical properties and a surface guiding cell migration for wound closure in combination with a high uptake capacity for wound exudate. Biocompatibility and significant wound healing effects were shown in interaction studies with human skin cells. As a new approach, analysis of the wound proteome in treated ex vivo human skin wounds clearly demonstrated a remarkable increase in wound healing biomarkers. Based on these findings, insulin-loaded electrospun wound dressings bear a high potential as effective wound healing therapeutics overcoming current challenges in the clinics.