Nano-MgO composites containing plasmid DNA to silence SNCA gene displays neuroprotective effects in Parkinson's rats induced by 6-hydroxydopamine

Parkinson's disease (PD) always causes dyskinesia and cognitive impairments. The alpha-synuclein (alpha-syn) accumulation, one of the main pathological characteristics of PD, may impair synaptic structural and synaptic functions. Nano-MgO composites has been reported to interfere alpha-syn expression. The present study is aim to investigate the roles of nano-MgO composites on cognitive impairments in PD rats. PD rats were formed by 6hydroxydopamine (6-OH DA) and alpha-syn expression were evaluated by Western blot. Hippocampal dendritic morphology was examined by Golgi staining. Morris water maze (MWM) test was applied to evaluate learning and memory abilities and population spike was recorded by electrophysiological records in vivo. The results showed that: 6-OH DA-treated up-regulated alpha-syn levels in striatum and hippocampus and increased the rotational times by APO, but nano-MgO composites could down-regulated alpha-syn levels. The overall length of dendritic and the total number of intersections were reduced by 6-OH DA, accompanied by the decrease of the dendritic spine density in hippocampal CA1, CA3 and DG regions. Interestingly, nano-MgO composites could alleviate the morphological damages of dendrites. In the MWM test, the escape latencies and the swimming distances in PD rats were increased as compared to the sham group, and nano-MgO composites could reduce the escapes latencies and the swimming distances. Furthermore, 6-OH DA reduced the amplitudes of long-term potentiation (LTP) in hippocampal CA1 region, and 6 mg/kg nano-MgO composites could improve LTP amplitudes. In conclusion, the current findings would be helpful to explore the roles of nano-MgO composites on neuroprotection in PD.