ผลของวิตามินอีต่อการตายของเซลล์ประสาทในปมประสาทไขสันหลังและการงอกใหม่ของเส้นประสาทภายหลังการบาดเจ็บในหนูแรท / จุฑามาศ ดอกแก้ว = Effect of vitamin E on dorsal root ganglion neuronal death and nerve regeneration after nerve injury in rats / Jutamard Dokkaew
After nerve injury, there is degeneration of nerve fibers called Wallerian degeneration followed by nerve regeneration. However, the recovery is limited by slow axonal regeneration and neuronal cell death. To improve the regeneration, many drugs have been testing. Vitamin E has antioxidant property which can reduce oxidative stress. In the past, several studies have shown the benefits of vitamin E in nervous system disorders in which oxidative stress plays a causal role. Oxidative stress is also found after nerve injury. Therefore, vitamin E may be beneficial to nerve injury. The aim of this study was to test the effect of vitamin E on dorsal root ganglion neuronal death and nerve regeneration after nerve injury in rats. After crushing the left sciatic nerve, vitamin E was gavaged 100, 500 and 1,000 mg/kg/day for 10 days. L4 DRG neurons was counted and vitamin E 500 and 1,000 mg/kg/day significantly reduced neuronal cell loss in DRG (p<0.01) compared with 100 mg/kg/day and control group. The next study used the same nerve injury model with vitamin E 500 mg/kg/day treatment for 3 weeks. Then, the functional recovery of sciatic nerve was tested by measuring foot prints for calculating the sciatic functional index (SFI). The results showed that vitamin E 500 mg/kg/day did not significantly improve the functional recovery. However, in the nerve morphometry study, fiber density and myelinated nerve fiber were significantly increased in the distal nerve segments in the vitamin E (p<0.05) compared with the control group. These data show the benefits of vitamin E on nerve injury by reducing neuronal cell loss and enhancing nerve fiber regeneration.