Premium
Human Bcl‐2 Protects Against AMPA Receptor‐Mediated Apoptosis
Author(s) -
Cheung Nam S.,
Beart Philip M.,
Pascoe Catherine J.,
John Christopher A.,
Bernard Ora
Publication year - 2000
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1046/j.1471-4159.2000.0741613.x
Subject(s) - ampa receptor , excitotoxicity , glutamate receptor , cnqx , staurosporine , biology , neuroprotection , programmed cell death , ionotropic effect , apoptosis , kainate receptor , microbiology and biotechnology , kainic acid , receptor , neuroscience , biochemistry , kinase , protein kinase a
Dysfunctions of the( S )‐α‐amino‐3‐hydroxy‐5‐methylisoxazole‐4‐propionate (AMPA)subtype of ionotropic receptor for the brain's major excitatoryneurotransmitter, L‐glutamate, occur in various neurological conditions. Wehave previously demonstrated that AMPA receptor‐mediated excitotoxicity occursby apoptosis and here examined the influence of the expression of cell deathrepressor gene Bcl‐2 on this excitotoxic insult. Using neuronalcortical cultures prepared from transgenic mice expressing the human Bcl‐2 gene, the influence of Bcl‐2 on AMPA receptor‐mediatedneuronal death was compared with that seen with staurosporine andH 2 O 2 . At day 6 cultures were exposed to AMPA (0.1‐100μ M ), and cellular injury was analyzed 48 h after insult usingphase‐contrast microscopy, a3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide viability assay,and DNA staining with 4,6‐diamidino‐2‐phenylindole and Sytox Green. AMPAproduced a concentration‐dependent increase in cell death that wassignificantly attenuated by human Bcl‐2 . AMPA (3 μ M )increased the number of apoptotic nuclei to 60% of control in wild‐typecultures, and human Bcl‐2 significantly decreased the number ofapoptotic nuclei to 30% of AMPA‐treated cultures. Human Bcl‐2 onlyprovided significant neuroprotection against neuronal injury induced by lowconcentrations of staurosporine (1‐10 n M ) andH 2 O 2 (0.1‐30 μ M ) and where neuronal deathwas by apoptosis, but not against H 2 O 2 ‐induced necrosis.Our findings indicate that overexpression of Bcl‐2 in primary cultured neurons protects in an insult‐dependent manner against AMPA receptor‐mediated apoptosis, whereas protection was not seen against more traumatic insults. This study provides new insights into the molecular therapeutics of neurodegenerative conditions.