L-DOPA is incorporated into brain proteins of patients treated for Parkinson's disease, inducing toxicity in human neuroblastoma cells in vitro
- Publication Type:
- Journal Article
- Experimental Neurology, 2012, 238 (1), pp. 29 - 37
- Issue Date:
Copyright Clearance Process
- Recently Added
- In Progress
- Closed Access
This item is closed access and not available.
Levodopa (l-dopa), a close structural analogue of the protein amino acid l-tyrosine, can substitute for l-tyrosine in protein synthesis and be mistakenly incorporated into newly synthesised proteins in vitro. We show that l- dopa-containing proteins are present in the brain in l-DOPA-treated Parkinson's disease patients and accumulate in specific brain regions. In vitro studies demonstrate that substitution of l-tyrosine residues in proteins with l-DOPA causes protein misfolding and promotes protein aggregation in SH-SY5Y neuroblastoma cells resulting in the appearance of autofluorescent bodies. We show that the presence of l-DOPA-containing proteins causes profound changes in mitochondria and stimulates the formation of autophagic vacuoles in cells. Unlike l-DOPA, which is toxic to cells through its ability to generate radicals, proteins containing incorporated l-DOPA are toxic to SH-SY5Y cells by a mechanism independent of oxidative stress and resistant to antioxidants. These data suggest that the accumulation of l-DOPA-containing proteins in vulnerable cells might negatively impact on cell function. © 2011 Elsevier Inc.
Please use this identifier to cite or link to this item: