TY - JOUR
T1 - Down-regulation of glutaredoxin by estrogen receptor antagonist renders female mice susceptible to excitatory amino acid mediated complex I inhibition in CNS
AU - Diwakar, Latha
AU - Kenchappa, Rajappa S.
AU - Annepu, Jayasree
AU - Saeed, Uzma
AU - Sujanitha, Ramakrishnan
AU - Ravindranath, Vijayalakshmi
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2006/12/13
Y1 - 2006/12/13
N2 - β-N-oxalyl-amino-l-alanine, (l-BOAA), an excitatory amino acid, acts as an agonist of the AMPA subtype of glutamate receptors. It inhibits mitochondrial complex I in motor cortex and lumbosacral cord of male mice through oxidation of critical thiol groups, and glutaredoxin, a thiol disulfide oxido-reductase, helps maintain integrity of complex I. Since incidence of neurolathyrism is less common in women, we examined the mechanisms underlying the gender-related effects. Inhibition of complex I activity by l-BOAA was seen in male but not female mice. Pretreatment of female mice with estrogen receptor antagonist ICI 182,780 or tamoxifen sensitizes them to l-BOAA toxicity, indicating that the neuroprotection is mediated by estrogen receptors. l-BOAA triggers glutathione (GSH) loss in male mice but not in female mice, and only a small but significant increase in oxidized glutathione (GSSG) was seen in females. As a consequence, up-regulation of γ-glutamyl cysteinyl synthase (the rate-limiting enzyme in glutathione synthesis) was seen only in male mouse CNS but not in females. Both glutathione reductase and glutaredoxin that reduce oxidized glutathione and protein glutathione mixed disulfides, respectively, were constitutively expressed at higher levels in females. Furthermore, glutaredoxin activity in female mice was down-regulated by estrogen antagonist indicating its regulation by estrogen receptor. The higher constitutive expression of glutathione reductase and glutaredoxin could potentially confer neuroprotection to female mice.
AB - β-N-oxalyl-amino-l-alanine, (l-BOAA), an excitatory amino acid, acts as an agonist of the AMPA subtype of glutamate receptors. It inhibits mitochondrial complex I in motor cortex and lumbosacral cord of male mice through oxidation of critical thiol groups, and glutaredoxin, a thiol disulfide oxido-reductase, helps maintain integrity of complex I. Since incidence of neurolathyrism is less common in women, we examined the mechanisms underlying the gender-related effects. Inhibition of complex I activity by l-BOAA was seen in male but not female mice. Pretreatment of female mice with estrogen receptor antagonist ICI 182,780 or tamoxifen sensitizes them to l-BOAA toxicity, indicating that the neuroprotection is mediated by estrogen receptors. l-BOAA triggers glutathione (GSH) loss in male mice but not in female mice, and only a small but significant increase in oxidized glutathione (GSSG) was seen in females. As a consequence, up-regulation of γ-glutamyl cysteinyl synthase (the rate-limiting enzyme in glutathione synthesis) was seen only in male mouse CNS but not in females. Both glutathione reductase and glutaredoxin that reduce oxidized glutathione and protein glutathione mixed disulfides, respectively, were constitutively expressed at higher levels in females. Furthermore, glutaredoxin activity in female mice was down-regulated by estrogen antagonist indicating its regulation by estrogen receptor. The higher constitutive expression of glutathione reductase and glutaredoxin could potentially confer neuroprotection to female mice.
KW - Excitatory amino acid
KW - Glutathione
KW - Mitochondrial dysfunction
KW - Neurodegeneration
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U2 - 10.1016/j.brainres.2006.10.015
DO - 10.1016/j.brainres.2006.10.015
M3 - Article
C2 - 17109834
AN - SCOPUS:33845188132
SN - 0006-8993
VL - 1125
SP - 176
EP - 184
JO - Brain Research
JF - Brain Research
IS - 1
ER -