Morphine prevents peroxynitrite-induced death of human neuroblastoma SH-SY5Y cells through a direct scavenging action.
N-ethyl-2-(1-ethyl-2-hydroxy-2-nitrosohydrazino)-ethanamine (NOC12), a nitric oxide donor, 3-morpholinosydnonimine (SIN-1), a generator of peroxynitrite (ONOO-), and peroxynitrite induced cell death accompanied by DNA fragmentation in human neuroblastoma SH-SY5Y cell cultures. Morphine prevented the cell death induced by SIN-1 or peroxynitrite, but not that induced by NOC12. The protective effect of morphine was concentration-dependent (10-100 microM), but was not antagonized by naloxone. The selective ligands for opioid receptor subtypes, [D-Ala2, N-Me-Phe4, Gly-ol5]enkephalin (DAMGO, micro-opioid receptor agonist), [D-Pen2,5]enkephalin (DPDPE, delta-opioid receptor agonist) and trans-(+/-)-3,4-dichloro-N-methyl-N-(2-[1-pyrrolidinyl]-cyclohexyl)benze neacetamide (U-50488, kappa-opioid receptor agonist) even at the concentration of 100 microM did not prevent the cell death induced by SIN-1. From measurement of the absorbance spectrum of peroxynitrite, the decomposition of peroxynitrite in 0.25 M potassium phosphate buffer (pH 7.4) was very rapid and complete within seconds. However, the absorbance was very stable in the presence of morphine. In addition, morphine inhibited peroxynitrite-induced nitration of tyrosine in a concentration-dependent manner. These results indicate that morphine rapidly reacts with peroxynitrite. The present study showed that morphine prevented peroxynitrite-induced cell death through its direct scavenging action, suggesting that morphine can protect cells against damage caused by peroxynitrite.
Kanesaki
T
T
The Second Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Osaka University, Suita, Japan.
Saeki
M
M
Ooi
Y
Y
Suematsu
M
M
Matsumoto
K
K
Sakuda
M
M
Saito
K
K
Maeda
S
S
D016923:Cell Death; D004347:Drug Interactions; D006801:Humans; D009020:Morphine / Q000378:metabolism / Q000494:pharmacology*; D009447:Neuroblastoma / Q000378:metabolism / Q000473:pathology*; D009566:Nitrates / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000494:pharmacology*; D009569:Nitric Oxide / Q000494:pharmacology; D017465:Receptors, Opioid, delta / Q000096:biosynthesis; D017473:Receptors, Opioid, kappa / Q000096:biosynthesis; D017450:Receptors, Opioid, mu / Q000096:biosynthesis; D014407:Tumor Cells, Cultured
D009566:Nitrates; D017465:Receptors, Opioid, delta; D017473:Receptors, Opioid, kappa; D017450:Receptors, Opioid, mu; C039642:peroxynitric acid; D009569:Nitric Oxide; D009020:Morphine