Partial enzyme digestion facilitates regeneration of crushed nerve in rat

Peripheral nerve injury is a life-changing disability with significant socioeconomic consequences. In this rat model, we propose that partial enzyme digestion can facilitate the functional recovery of a crushed nerve. The sciatic nerves were harvested and in vitro cultured with the addition of Liberase to determine the appropriate enzyme amount in the hyaluronic acid (HA) membrane. Then, the sciatic nerve of adult male Sprague-Dawley rats was exposed, crushed, and then treated with partial enzyme digestion (either 0.001 or 0.002 unit/mm2 Liberase-HA membrane). The sciatic function index (SFI) for functional recovery of the sciatic nerve was evaluated. After 2 h of in vitro digestion, fascicles and axons were separated from each other, with the cells mobilized. Greater destruction of histology structures occurred in the high enzyme (Liberase-HA membrane at 0.002 unit/mm2) group at 24 h than in the low enzyme (0.001 unit/mm2) group at 48 h. In the SFI evaluation, the improvement in 0.001 unit/mm2 Liberase group was significantly better than control and 0.002 unit/mm2 Liberase group. Our study demonstrated that appropriate enzyme digestion had a significantly faster and earlier recovery.

Morphological Studies on Crushed Sciatic Nerve of Rabbits with Electroacupuncture or Diclofenac Sodium Treatment

Sciatic nerves of 15 rabbits were crushed by Halsted straight mosquito hemostat with 8-11 Newton force for 60 seconds on a point 5 mm above the knee joint, and then the rabbits were equally divided into three groups. The acupuncture group was treated by electroacupuncture on Huan Tiao and Wei Zhong points (25 minutes/day) for 7 days. The medicine group was treated with intramuscular administration of dicofenac sodium (15 mg) daily for 7 days. The control group was not treated. After treatment, the distal parts of crushed nerve were examined under light microscope, the densities of normal myelinated fibers in 0.126 mm2 were counted, and the diameters of 20 normal myelinated fibers were measured for each animal. The results showed that the mean densities were 176.2 ± 5.953 in the acupuncture group, 118.2 ± 10.878 in the medicine group and 101.4 ± 8.548 in the control group. The mean values were significantly different between the acupuncture and medicine groups ( p < 0.01) and highly significant difference between the acupuncture and control groups ( p < 0.001); but there was no significant difference between the medicine and control groups ( p > 0.05). There are more small myelinated fibers (0–9 μm) in the acupuncture group than in the medicine and control groups ( p = 0.0028). The results revealed and confirmed that acupuncture promotes nerve regeneration; diclofenac sodium did not show such an effect. The present study demonstrates the positive effect of acupuncture on regeneration of a crushed sciatic nerve in the rabbits. And acupuncture is a better treatment for regeneration of crushed nerve than diclofenac sodium.