Crocin Enhanced Functional Recovery after Sciatic Nerve Crush Injury in Rats

Crocin is a constituent of saffron and has many biological functions. The present study aimed to investigate the effects of intraperitoneal (IP) injection of crocin on sciatic nerve regeneration in male Wistar rats. Fifty-four rats were divided into 9 groups: groups 1-4 (intact + normal saline and intact + crocin at doses of 5, 20 and 80 mg/kg, respectively); group 5 (sham surgery + normal saline); groups 6-9 (crush + normal saline and crush + crocin at doses of 5, 20 and 80 mg/kg, respectively). Normal saline and crocin were IP injected for 10 consecutive days after induction of a standard crush injury in left sciatic nerve. Footprints were obtained 1 day before and weekly after induction of nerve injury for evaluation of sciatic functional index (SFI). Blood samples were taken for evaluation of malondialdehyde (MDA) levels. Histopathological changes of sciatic nerve were investigated by light microscopy. Sciatic nerve crush-injured rats showed SFI values reduction, increased plasma MDA levels and produced Wallerian degeneration in sciatic nerve. Crocin at a dose of 5 mg/kg had no significant effects. At doses of 20 and 80 mg/kg, crocin accelerated the SFI recovery, decreased MDA levels and reduced Wallerian degeneration severity. The present study suggests that the neuroprotective effects afforded by crocin may be due in part to reduction of free radicals-induced toxic effects