Studies on neuronal apoptosis in primary forebrain cultures: neuroprotective/anti-apoptotic action of NR2B NMDA antagonists.
While the role of apoptosis in neuronal injury is continually being re-defined, approaches to intervene in the progression of apoptotic injury have been documented to provide neuroprotection against a variety of insults. The present studies were undertaken to systematically study the effects of certain neuroprotective agents against neuronal apoptosis mediated by staurosporine (ST). ST (0.01-5 micro M) produced a dose-related apoptotic injury (as characterized by cellular morphology, 'Comet' assay analysis [single cell gel electrophoresis] and caspase-3 activation) in primary cultures of forebrain neurons. ST significantly increased caspase-3 activity. The NMDA receptor subtype non-selective antagonist dizocilpine [(+) MK-801; 0.1-50 micro M] and a novel sodium channel blocker RS100642 (1.0-250 micro M) had no significant effects against ST-induced neurotoxicity. Conversely, NR2B-selective NMDA receptor antagonists CGX-1007 (0.01-50 micro M) and ifenprodil (0.01-50 micro M) provided dose-dependent neuroprotection against ST-induced neurotoxicity (as measured by neuronal viability and comet assay analysis). CGX-1007 had no significant effect on ST-induced caspase-3 activity; however, ifenprodil did block activation of caspase-3. These studies demonstrate that NR2B NMDA receptor antagonists are anti-apoptotic and may mediate their action via mechanism(s) that are dependent or independent of caspase-3 activation.
Dave
Jitendra R
JR
Department of Neuropharmacology and Molecular Biology, Division of Neurosciences, Walter Reed Army Institute of Research, Silver Spring, MD 20910-7500, USA. jit.dave@na.amedd.army.mil
Williams
Anthony J
AJ
Moffett
John R
JR
Koenig
Michael L
ML
Tortella
Frank C
FC
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002478:Cells, Cultured; D020916:Conotoxins / Q000494:pharmacology*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology*; D005260:Female; D008801:Mexiletine / Q000031:analogs & derivatives / Q000494:pharmacology; D009474:Neurons / Q000166:cytology* / Q000201:enzymology; D018696:Neuroprotective Agents / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology; D011247:Pregnancy; D016548:Prosencephalon / Q000166:cytology; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors*; D026941:Sodium Channel Blockers / Q000494:pharmacology; D019311:Staurosporine / Q000494:pharmacology
D020916:Conotoxins; D004791:Enzyme Inhibitors; D018691:Excitatory Amino Acid Antagonists; C121001:NR2B NMDA receptor; D018696:Neuroprotective Agents; D010880:Piperidines; C475846:RS100642; D016194:Receptors, N-Methyl-D-Aspartate; D026941:Sodium Channel Blockers; D008801:Mexiletine; D016291:Dizocilpine Maleate; C055407:conotoxin GV; C505410:Casp3 protein, rat; D053148:Caspase 3; D020169:Caspases; D019311:Staurosporine; C010739:ifenprodil