The Role of Dental Pulp Stem Cells in Sciatic Nerve Regeneration in Rats : Functional and Histological Analysis

Abstract

Objective Trauma is the most common cause of peripheral nerve injuries. Autografts are considered the gold standard for bridging nerve defects. Allografts are often used due to limited numbers of autografts and potential donor site morbidity. Lack of adequate neurogenic growth factors, especially in long length grafts, is an important reason for poor surgical outcomes. Stem cells with their ability to secrete neurotrophic growth factors can decrease inflammation and guide regeneration and have shown good results in nerve repair. Dental pulp stem cells (DPSC) are a viable option for nerve repair. We studied regeneration in sciatic nerve injuries in rats using DPSCs. Method Total 60 Sprague Dawley rats were included in the study. Sciatic nerve of right hindlimb was cut and repaired with allograft from Wistar rat. Depending on the type of allograft and timing of nerve repair, subjects were divided into six groups. Recovery was assessed after 12 weeks with general assessment, step length ratio, nerve conduction velocity, histopathological analysis, and plasma level of proinflammatory cytokines like tumor necrosis factor-α, interleukin-6 and interferon-γ. Results Incidence of trophic ulcers, contractures, and autotomy was lesser in DPSC-implanted allografts. Step length ratio improved in stem cell-implanted allografts. Nerve conduction velocity improved in DPSC-implanted allografts more than in allografts without stem cells (p < 0.05). Myelin loss was lesser in stem cell-implanted groups. Proinflammatory cytokine levels were lesser in the stem cell group, though the difference was not statistically significant. Conclusion DPSC-implanted allografts are viable, safe, and effective in traumatic peripheral nerve regeneration with better functional, electrophysiological, and histological outcomes