Polyurethane/Gelatin Nanofiber Neural Guidance Conduit in Combination with Resveratrol and Schwann Cells for Sciatic Nerve Regeneration in the Rat Model

Peripheral nerve injury is a serious challenge which influences 2.8 percent of trauma patients. Tissue engineering of peripheral nerves mainly focuses on axonal regeneration via various nerve guides. The aim of this study is to evaluate a novel polyurethane (PU)/gelatin nanofibers (GNFs) conduit's potential combination with resveratrol (RVT) for sciatic nerve regeneration in the rat. Platelet-rich plasma (PRP) was used as a carrier for RVT. Different tests like contact angle, tensile strength etc. was used to evaluate properties of PU/GNFs conduits. In addition, the electron microscopy, MTT assay, and DAPI staining revealed its compatibility with Schwann cells. 24 male Wistar rats were allocated into four groups (n=6) (1) PU/GNF/PRP/Schwann cell, 2) PU/GNF/Schwann cell/PRP/RVT, 3) Positive control, and 4) Negative control in order to assess sciatic functional index (SFI), hot plate latency, electromyographical (EMG), the percentage of wet weight-loss of gastrocnemius muscle and histopathological studies using hematoxylin-eosin staining. The results represented sciatic functional index (SFI), hot plate latency, electromyographical improved significantly in group 1 and 2 compared to the negative control group. Histopathological findings showed remarkable improvements in myelin sheath regeneration and fibers condition in group 1 and 2 compared to the negative control group. Group 2 showed more resemblance to the normal sciatic nerve, with well-arranged fibers and an intact myelin sheath. This study successfully applied PU/GNFs/PRP/RVT conduits as a potential biocompatible nerve guide with proper mechanical properties, biocompatibility, and biodegradability that enhanced injured sciatic nerve's recovery rate.