Curcumin improves neurofunctions of 6-OHDA-induced parkinsonian rats

Our previous study has demonstrated that curcumin (CM), a natural ingredient isolated from Zingiberaceae, exerts the effect of inhibiting hippocampal injury in 6-hydroxydopamine (6-OHDA)-induced parkinsonian rat. However, the potential effect of CM on 6-OHDA-injured substantia nigra (SN) needs to be investigated. This study aimed to further evaluate the therapeutic effectiveness of CM against damaged SN in rats. Methodologically, Parkinson's disease (PD) rat was prepared by using a surgical approach of injecting 6-hydroxydopamine (6-OHDA) into the SN. Morris water maze, open-field assays, and rotarod test were used to assess the neurobehavioral manifestations. Neurotransmitter contents in the SN were determined by using the biochemical tests. Western blotting was employed to evaluate the target protein expressions. The representative data showed that CM protected against 6-OHDA-induced neural impairments in the SN, as evidenced by improved memory abilities, elevated intercalatum levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and reduced concentration of malonaldehyde (MDA). In addition, dopamine (DA) and acetylcholine (ACh) levels were increased in the SN. Moreover, intercalatum heat shock protein 70 (HSP70) was lowered, while basic fibroblast growth factor (bFGF), nerve growth factor (NGF) and receptor tyrosine kinase A (TrkA) expressions were up-regulated, respectively. Taken together, the findings indicate that curcum in exerts neuroprotection in the SN via ameliorating neurofunctions of PD rats.