A vitamin E-deficient diet affects nerve regeneration in rats

Degenerative changes in the neuromuscular system have been found in animals and humans with vitamin E (E) deficiency. This morphologic study examined the effect of dietary E on the regeneration of peripheral nerves in male Sprague-Dawley rats. After feeding an E-sufficient diet ( dl-α-tocopheryl acetate 50 mg/kg diet) for 6 d, 24 rats were randomly and equally assigned to one of three groups: control (CTRL) fed an E-sufficient diet for 43 d without surgery, normal (NE) fed an E-sufficient diet, or low (LE) fed an E-deficient diet ( dl-α-tocopheryl acetate 0 mg/kg diet). After 22 d of feeding, NE and LE had surgical compression of the right sciatic nerve and continued eating for 15 d. On day 43, the right triceps surae muscles and a segment of the right sciatic nerve were removed, then all rats were euthanized. The nerve and muscles were processed for morphologic analyses. Presurgery and postsurgery LE ate less food ( P < 0.048 and P < 0.001, respectively), which resulted in a lower body weight gain ( P < 0.0002). LE had irregularly shaped and less myelinated axons than NE ( P < 0.0001) and CTRL ( P < 0.0001). The LE plantaris muscle had less type II fibers when compared with NE ( P < 0.007) and CTRL ( P < 0.03). The results suggest that an E-deficient diet affects food intake, impairs nerve regeneration, and decreases type II fibers, whereas an E-sufficient diet contributes to normal axon regeneration.