Neuroprotection by(-)-deprenyl and related compounds

There is an increasing number of data by in vitro and in vivo experiments, indicating that (-)-deprenyl is neuroprotective to dopamine neurons, even though detailed mechanism remains to be clarified. In this paper neuroprotection by (-)-deprenyl and structurally related compounds was examined in concern with the suppression of apoptosis induced by a reactive oxygen species, peroxynitrite generated from SIN-1. The apoptotic DNA damage was quantitatively determined using dopaminergic SH-SYSY cells and by a single cell gel electrophoresis (comet) assay. DNA damage induced by peroxynitrite was proved to be apoptotic by prevention of the damage by cycloheximide or actinomycin-D. (-)-Deprenyl and other propargylamines protected the cells from apoptosis in a dose-dependent way. (-)-Deprenyl protected the cells even after it was washed out, suggesting that it may initiate the intracellular process to repress the apoptotic death program. The study on the structure-activity relationship of(-)-deprenyl analogues revealed that a N-propargyl residue with adequate size of hydrophobic structure is essentially required for the anti-apoptotic activity. These results suggest that (-)-deprenyl and related compounds may protect neurons from apoptosis and be applicable to delay the deterioration of neurons during advancing ageing and in neurodegenerative disorders. (C) 1999 Published by Elsevier Science S.A. All rights reserved.