Neuroprotective effect of curcumin on hippocampal injury in 6-OHDA-induced Parkinson's disease rat

Clinically, Parkinson's disease (PD)-related neuronal lesions commonly occur. The purpose of this study is to investigate potential therapeutic effect of curcumin against hippocampal damage of 6-hydroxydopamine (6-OHDA)-PD rat model. These results showed that curcumin significantly increased the body weight of 6-OHDA-impaired rats (P < 0.01), and reversed the anhedonia in rats induced by 6-OHDA impairment (P < 0.01). Meanwhile, behavioral manifestations of curcumin-treated PD rats were effectively ameliorated as shown in open field test (P < 0.01). In addition, curcumin increased the contents of monoaminergic neurotransmitters (P < 0.01), such as dopamine (DA) and norepinephrine (NE), in hippocampal homogenate through high performance liquid chromatography (HPLC) assay. Curcumin effectively alleviated the 6-OHDA-induced hippocampal damage as observed in hematoxylin-eosin (H&E) staining. Furthermore, curcumin obviously up-regulated hippocampal brain derived neurotrophic factor (BDNF), TrkB, phosphatidylinositide 3-kinases (PI3K) protein expressions, respectively as shown in Western blot analysis. These findings demonstrated that curcumin mediated the neuroprotection against 6-OHDA-induced hippocampus neurons in rats, which the underlying mechanism is involved in activating BDNF/TrkB-dependent pathway for promoting neural regeneration of hippocampal tissue.