Improvement of peripheral nerve regeneration following nerve repair by silicone tube filled with curcumin: A preliminary study in the rat model

The objective was to assess the effect of locally administered curcumin on peripheral nerve regeneration and functional recovery. Thirty male healthy white Wistar rats were divided into two experimental groups (n = 15), randomly: In control group (CG), the left sciatic nerve was exposed and transected proximal to tibio-peroneal bifurcation leaving a 10-mm gap. Proximal and distal stumps were each inserted into a silicone tube and filled with 10 μL sterilized olive oil. In treatment group (TG), the graft was filled with 10 μL curcumin (5 mg/mL) solved in olive oil. Each group was subdivided into three subgroups of five animals each and regenerated nerve fibers were studied 4, 8 and 12 weeks after surgery. Behavioral testing, sciatic nerve functional study, static sciatic index (SSI), gastrocnemius muscle mass and morphometric indices confirmed faster recovery of regenerated axons in TG than CG group (p < 0.05). In immunohistochemistry, location of reactions to S-100 in TG was clearly more positive than that in CG group. When loaded in a silicone tube, curcumin improved functional recovery and morphometric indices of sciatic nerve. Curcumin is readily available and its local application is easily performed without limitations of its poor bioavailability in systemic administration.