effect of crocetin on functional recovery in the rat model of sciatic nerve crush injury: comparison with vitamin c

Crocetin (crt) is one of the active chemical compounds of saffron and has many biological effects such as antioxidant property. the present study investigated the effects of crt on crushed sciatic nerve function. vitamin c (vit c) was used as an antioxidant drug. material and methods: thirty rats were divided into six groups (n=5) including intact, sham, crush, crt 7.50, crt 30.00 and vit c 100. in anesthetized rats, right sciatic nerve was crushed using a small hemostatic forceps. with no significant differences, sfi at the test days was around 0.00 in intact and sham groups. in the crush group, sfi was -114.72 ± 11.28 at days 5 and reached to -82.46 ± 12.04 at day 20 after crush injury and showed significant differences (p < 0.001) with intact and sham groups. the crt (7.50 mg kg-1) did not affect time-point sfi. the crt (30.00 mg kg-1) significantly increased the decreased sfi to -44.43 ± 5.42 (p < 0.05) at day 5 and reached it to the intact and sham groups value (-7.09 ± 2.68, p > 0.05) at day 20. the vit c (100 mg kg-1) significantly increased the decreased sfi to -54.71 ± 6.08 (p < 0.05) at day 5 and reached it to the intact and sham groups value (-6.32 ± 3.13, p > 0.05) at day 20 (figure 1a). when the average of sfi was analyzed by one-way anova, a significant (p < 0.0001) difference was observed between groups. subsequent analysis by turkey’s test revealed that crt (30.00 mg kg-1) and vit c (100 mg kg-1) significantly (p < 0.001) decreased the increased sfi, whereas crt (7.50 mg kg-1) was without effect. the severities of sciatic nerve degeneration (edema, vacuolation and ellipsoid bodies) and gastrocnemius muscle atrophy were ameliorated, and the increased mda level and the decreased sod activity in the serum were restored by 20 consecutive days oral administration of 30.00 mg kg-1 crt and 100 mg kg-1 vit c. no significant differences were observed between 30.00 mg kg-1 and 100 mg kg-1 vit c. it is concluded that crt and vit c produce similar improving effects on crushed-injured sciatic nerve function. inhibition of oxidative stress, enhancement of endogenous antioxidant activity might be involved in improving effects of crt and vit c.