Protective effect of crocin on cuprizone-induced model of multiple sclerosis in mice.

Crocin is the main bioactive components of the saffron which has positive role in the nervous system; however, its neuroprotective activity is not fully elicited. So, the aim of the current study was to determine effects of the crocin on reflexive motor and anti-depressive behaviors as well as serum and brain tissue antioxidant activities in cuprizone-induced (CPZ) model of multiple sclerosis (MS) mice. Forty male C57BL/6 mice were randomly assigned into 4 groups. Mice in the control group were received normal diet. In group 2, mice received normal diet and orally received crocin (100 mg/kg) 3 times per week for 5 weeks. In group 3, CPZ-induced demyelination was done by chew palate containing 0.2% (w/w) CPZ for 5 weeks. In group 4, mice feed CPZ containing diet and orally received crocin (100 mg/kg) three times per for 5 weeks. After determination of the MS signs, reflexive motor behavior and depressive tests were done. Also, serum and brain tissue antioxidant activity was determined. According to the data, CPZ had negative effects on hind-limb foot angle, hind- and front-limb suspension, surface righting, grip strength, and negative geotaxis while crocin improved it. Co-administration of the CPZ + crocin reversed effect of the CPZ on the reflexive motor behaviors. CPZ increased immobility time in the forced swimming test (FST) and tail suspension test (TST), while co-administration of the CPZ + crocin reversed effect of the CPZ on immobility time. CPZ decreased number of cross in open field test (OFT) and spending time on rotarod, while co-administration of the CPZ + crocin reversed effect of the CPZ. Malondialdehyde (MDA) production increased, and glutathione peroxidase (GPx), superoxide dismutase (SOD), and total antioxidant status (TAS) levels decreased in serum and brain tissue of the mice treated with CPZ. Pretreatment with crocin decreased adverse effect of the CPZ on serum and brain tissue antioxidants. These results suggested crocin has protective effect against CPZ-induced MS in mice.