Signaling pathway analysis of MPP+-treated human neuroblastoma SH-SY5Y cells

Analyzing Apomorphine-Mediated Effects in a Cell Model for Parkinson's Disease with Partial Least Squares Structure Equation Modeling

Genome-wide gene expression data for cell model of Parkinson's disease (PD) have considerably improved our understanding of the underlying molecular mechanisms involved in cell death during PD neurodegeneration. Apomorphine (APOM), a nonselective dopamine agonist, has been used to treat patients with advanced PD showing no response to levodopa or other dopamine agonists. Although APOM plays a role as a free radical scavenger with neuroprotective effect, it has been reported that long-term use of APOM in PD treatment brings about side effects such as nausea and orthostatic hypotension. For safe use of APOM in PD treatment, it is crucial to understand the underlying molecular mechanisms of APOM in PD. In this study, two groups of microarray data including PD cell model and APOM added PD cell model were used to survey mediation effects of APOM in PD cell model. Mediation analysis between disease genes obtained from PD cell model and drug genes obtained from APOM added PD cell model was carried out with shortest path model on KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways and partial least squares structure equation modeling. Our results suggest that drug genes responding to APOM might contribute to negative regulation of disease genes by direct or indirect ways.

The Neuroprotective Role of Insulin Against MPP(+) -Induced Parkinson's Disease in Differentiated SH-SY5Y Cells

Parkinson's disease (PD) is a common chronic neurodegenerative disorder associated with aging that primarily caused by the death of dopaminergic neurons in the substantia nigra pars compacta (SN). Retinoic acid (RA)-differentiated human neuroblastoma SH-SY5Y cells (SH-SY5Y+RA) have been broadly utilized in studies of mechanisms of the pathogenesis underlying 1-Methyl-4-phenyl pyridinium (MPP(+))-induced PD models. Here, we investigated the neuroprotective mechanisms of insulin on MPP(+)-induced neurotoxicity on SH-SY5Y+RA cells. Recent studies suggest that insulin has a protective effect against oxidative stress but not been elucidated for PD. In this study, pretreatment of insulin prevented the cell death in a dose dependent manner and lowered nitric oxide (NO) release, reactive oxygen species (ROS), and calcium ion (Ca(2+)) influx induced by MPP(+). Insulin also elevated tyrosine hydroxylase (TH) and insulin signaling pathways in dopaminergic neuron through activating PI3K/Akt/GSK-3 survival pathways which in turn inhibits MPP(+)-induced iNOS and ERK activation, and Bax to Bcl-2 ratio. These results suggest that insulin has a protective effect on MPP(+)-neurotoxicity in SH-SY5Y+RA cells.