Hazard
Toxic by ingestion.
Description
Edaravone was marketed in Japan for improving neurologic recovery
following acute brain infarction. Currently, several agents classified as neuroprotectants
and acting by diverse mechanisms (inhibition of glutamate release, blockade of calcium
channels, lazaroids) have been marketed for treating the outcomes of brain damage due to
trauma, ischemia or cardiac arrest. Edavarone is the first antioxidant with free radical
scavenging activity to be introduced for this pathology. This previously described molecule
(in particular as norantipyrine, one of three metabolites of antipyrine in mammals) can be
simply prepared by direct cyclization of phenylhydrazine with alkylacetoacetate. Edarevone
is a lipophilic agent, readily accessible to brain tissue, that is capable of reducing edema
in the brain following ischemia by blocking the arachidonic acid cascade triggering
peroxidative neurodegeneration. Interestingly, this agent has been shown to quench active
oxygen species in endothelial cell homogenate, as well as inhibiting in vitro lipid peroxidative disintegration of membranes, so making this compound effective during
reperfusion following ischemic injury. As an additional indication, phase III trials started with edaravone for increasing the chance of recovery after subarachnoid hemorrhage.
Chemical Properties
Off white to light yellow powder
Originator
Mitsubishi Pharma (Japan)
Uses
antioxidant, lipoxygenase inhibitor
Uses
Edaravone inhibits the disease activity in rheumatoid arthritis.
Definition
ChEBI: A pyrazolone that is 2,4-dihydro-3H-pyrazol-3-one which is substituted at positions 2 and 5 by phenyl and methyl groups, respectively.
General Description
A free radical scavenger and antioxidant that reduces post-ischemic brain injury. Inhibits iron-dependent peroxidation in rat brain homogenates (IC50 = 15 μM). Inhibits mitochondrial permeability transition pore.
Flammability and Explosibility
Notclassified
Biological Activity
A radical scavenger and antioxidant which is able to protect against the effects of ischemia, probably by inhibiting the lipoxygenase system. Protects against MPTP-induced neurotoxicity.
Biochem/physiol Actions
Product does not compete with ATP.
Safety Profile
Moderately toxic by ingestion andintraperitoneal routes. An eye irritant. When heated todecomposition it emits toxic fumes of NOx.
Purification Methods
Crystallise the pyrazolone from hot H2O, EtOH or EtOH/water (1:1). It complexes with metals. [Veibel et al. Acta Chim Scand 6 1066 1952, Beilstein 24 II 9, 24 III/IV 71.]
References
1) Watanabe et al. (1994), Protective effects of MCI-186 on cerebral ischemia:possible involvement of free radical scavenging and antioxidant actions; J. Pharmacol. Exp. Ther., 268 1597
2) Yoshida et al. (2006) Neuroprotective effects of edaravone:a novel free radical scavenger in cerebrovascular injury; CNS Drug Reviews, 12 9
3) Kawasaki et al. (2007) Edaravone (3-Methyl-1-phenyl-2-pyrazolin-5-one), a Radical Scavenger, Prevents 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced Neurotoxicity in the Substantia Nigra but Not the Striatum; J. Pharmacol. Exp. Ther., 322 274
