Abstract
The present study was conducted to characterize the possible interaction of Al3+ and Fe2+ with synthetic melanin in the potentiation of lipid peroxidation in liposomes and rat caudate-putamen homogenates. Al3+ stimulated melanin-initiated lipid peroxidation as measured by the production of 2-thiobarbituric acid-reactive substances (TBARS) and conjugated dienes. The effect of Al3+ was dependent on melanin (10-100 μg/ml) and Al3+ (2.5-250 μM) concentrations and no synergism between Fe2+ and Al3+ was observed. The prooxidant effect of Al3+ was partially inhibited by superoxide dismutase indicating the involvement of Q2/·-, Ga3+ and Be2+ which can increase NADH oxidation in the presence of Q2/·-, also were shown to stimulate melanin-initiated TBARS production. Based on the effect of Al3+ and other non redox metals, we suggest that Al3+ does not act through either the induction of melanin free radicals, or the induction of changes in membrane physical properties. Results show that Al3+ enhances melanin-initiated lipid peroxidation in part through an interaction with O2/·- generated from the autoxidation of melanin. We speculate that Al3+ contributes to neuromelanin-mediated oxidative damage in dopaminergic neurons and subsequent neuronal degeneration and death in Parkinson's disease.
Original language | English (US) |
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Pages (from-to) | 1001-1008 |
Number of pages | 8 |
Journal | Neurochemical Research |
Volume | 24 |
Issue number | 8 |
DOIs | |
State | Published - 1999 |
Externally published | Yes |
Keywords
- Aluminum
- Free radicals
- Lipid peroxidation
- Melanin
- Neuromelanin
- Parkinson
ASJC Scopus subject areas
- Neuroscience(all)
- Biochemistry