Insulin-Loaded Polyurethane Tubes for Urethra Reconstruction: An In Vitro Evaluation

Abstract

High demand for urethra tissue grafts and their low availability has driven efforts to engineer these constructs In Vitro. Inspired by the regenerative functions of insulin, a bioactive artificial urethra was developed via electrospinning of polyurethane and polyvinyl alcohol solutions for sustained delivery of this hormone. Insulin was loaded into polyvinyl alcohol solution and co-electrospun with polyurethane solution via a double nozzle electrospinning device. The produced sheets were rolled up and shaped into tube-like structures. Various experiments were used for characterization of the produced urethra. Cell culture studies showed that the produced sheets were biocompatible with human urothelial cells and supported their adhesion and proliferation. Gene expression analysis showed that human urothelial cells cultured on insulin-delivering scaffolds had the highest relative gene expression for VEGF, b-FGF, and TGF-β genes; while, they significantly reduced fibrosis associate genes such as Collagen type I, Collagen type III, and elastin. This preliminary research suggests potential applicability of insulin-loaded Polyurethane/PVA scaffolds in urethra reconstruction.