Myristicin-induced neurotoxicity in human neuroblastoma SK-N-SH cells

Myristicin, 1-allyl-3,4-methylenedioxy-5-methoxybenzene, is a naturally occurring alkenylbenzene compound found in the nutmeg. The present study was conducted to assess the cytotoxic and apoptotic effects of myristicin on the human neuroblastoma SK-N-SH cells. We found that a dose-dependent reduction in cell viability occurs at myristicin concentration > or =0.5 mM in SK-N-SH cells. Apoptotic cell death was confirmed using DNA fragmentation, terminal deoxyribonucelotidyl transferase-mediated dUTP nick end labeling and by 4,6-diamidino-2-phenylindole staining. Microscopy was used to observe apoptotic cell morphology. Western blotting was used to investigate the protein expression of known apoptotic mediators including cytochrome c, caspase-3, and PARP. The apoptosis triggered by myristicin was accompanied by an accumulation of cytochrome c and by the activation of caspase-3. The results obtained suggest that myristicin induces cytotoxicity in human neuroblastoma SK-N-SH cells by an apoptotic mechanism. This myristicin-induced apoptosis provides further insight of the molecular mechanisms of myristicin toxicity.