The protection of curcumin in nigral dopaminergic neuronal injury of mice model of Parkinson disease

Objective To investigate the neuroprotective effects of curcumin on dopaminergic neuronal injury of parkinsonian mice model induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP). Methods The C57BL mice were divided into 4 groups: MPTP group, MPTP + curcumin group, saline control group and solvent control (MPTP + DMSO) group. The number of tyrosine hydroxylase (TH) positive neurons and glial fibrillary acidic protein (GFAP) positive neurons in substantia nigra-striatum system was measured by immunohistochemistry. The expression levels of TH, inducible nitric oxide synthase (iNOS) and GFAP in substantia nigra-striatum system were detected by Western blotting. Results The number of TH positive neurons and GFAP positive neurons in the substantia nigra was significantly reduced in MPTP group than that in MPTP + curcumin and saline control groups (P 0.05, for all). After different doses of curcumin treatment (5 mg/kg, 50 mg/kg and 150 mg/kg), TH expression level obviously increased in striatum, and iNOS and GFAP expression levels markly decreased in subsfantia nigra, the differences with MPTP group were all significant (P 0.05), but the differences between MPTP group and MPTP + DMSO group were not siginifcant (P 0.05). Conclusion Curcumin could effectively block the loss of dopaminergic neurons in the parkinsonian mice model induced by MPTP. The mechanism may be related to its antioxidantion and anti-inflammatory activities.