Effects of edaravone on N-methyl-D-aspartate (NMDA)-mediated cytochrome c release and apoptosis in neonatal rat cerebrocortical slices.
N-Methyl-D-aspartate-mediated neurotoxicity is known to involve nitric oxide production and to be augmented in an environment of reactive oxygen species. We used TUNEL staining and homogenous cytosolic immunoreactivity of cytochrome c in an acute brain slice preparation to investigate the influence of edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one), a free radical scavenger, on N-methyl-D-aspartate-induced apoptosis. Cerebrocortical slices were obtained from parietal lobes of 7-day-old Sprague-Dawley rats, superfused with well-oxygenated artificial cerebrospinal fluid, and metabolically recovered. Subsequent 30-min exposures to 10 microM N-methyl-D-aspartate in treated and untreated slices were followed by 4 h of recovery superfusion with oxygenated artificial cerebrospinal fluid. Outcomes were compared for three groups of slices: "the N-methyl-D-aspartate-only group"; "the edaravone treatment group", which had 20 microM edaravone present throughout and subsequent to N-methyl-D-aspartate exposure; the "control group", in which slices were superfused only with oxygenated artificial cerebrospinal fluid. At the conclusion of recovery (t = 4 h), the percentage of TUNEL-positive cells in the edaravone treatment group (7.0+/-3.3%) was significantly reduced from the percentage for the N-methyl-D-aspartate-only group (21.9+/-4.1%), and insignificantly greater than the percentage for the control group (3.4+/-2.1%). Percentages of cytochrome c positive cells at t = 1 h were significantly increased (p < 0.01) in the N-methyl-d-aspartate-only group (30.6+/-1.9%) compared to percentages for both the control group (11.4+/-2.6%) and the edaravone treatment group (15.2+/-2.1%). Edaravone's reduction in TUNEL staining and cytochrome c release provides evidence of reactive oxygen species mechanisms and antioxidant benefits in cytochrome c-mediated apoptosis during N-methyl-D-aspartate excitotoxicity.
Nakano-Okuda
Yumi
Y
Department of Pediatrics, Kyoto Prefectural University of Medicine, Japan. YFA66746@nifty.com
Hasegawa
Koh
K
Hirai
Kiyoshi
K
Kanai-Ochiai
Rika
R
Morimoto
Masafumi
M
Sugimoto
Toru
T
D000818:Animals; D000831:Animals, Newborn; D000983:Antipyrine / Q000031:analogs & derivatives* / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D002540:Cerebral Cortex / Q000166:cytology / Q000378:metabolism* / Q000473:pathology; D045304:Cytochromes c / Q000378:metabolism*; D000077553:Edaravone; D016166:Free Radical Scavengers / Q000378:metabolism*; D006801:Humans; D020287:In Situ Nick-End Labeling; D016202:N-Methylaspartate / Q000378:metabolism / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley
D016166:Free Radical Scavengers; D016202:N-Methylaspartate; D045304:Cytochromes c; D000077553:Edaravone; D000983:Antipyrine