The effects of morphine on Parkinson’s-related genes PINK1 and PARK2

BACKGROUND: Parkinson’s disease (PD) continues to be an important neurological disorder. It is caused by the loss of dopaminergic neurons in the substantia nigra. Dopamine, the neurotransmitter produced from dopaminergic neurons, is a major precursor of endogenous morphine. There are approximately 18 genes associated with PD; their roles have not yet been completely established. PARK2 is a gene that encodes for the protein parkin, and PINK1 is a gene that encodes for PTEN-induced putative kinase 1. MATERIAL/METHODS: Our objective was to determine if morphine treatment of HTB-11 cells affects the expression of PINK1 and PARK2. HTB-11 cells were treated with 10(−7) M morphine for 2 h and a microarray analysis was conducted. To verify the microarray analysis, 3 Q-PCR trials were run using 10(−6) M naloxone, morphine (10(−7) M), or a naloxone/morphine mix. RESULTS: In both the microarray analysis and the Q-PCR analysis, PARK2 was up-regulated and PINK1 was down-regulated. CONCLUSIONS: Morphine can affect the expression of PD-associated genes.