TY - JOUR
T1 - Impairment of glutamate transport and increased vulnerability to oxidative stress in neuroblastoma SH-SY5Y cells expressing a Cu,Zn superoxide dismutase typical of familial amyotrophic lateral sclerosis
AU - Sala, Gessica
AU - Beretta, Simone
AU - Ceresa, Chiara
AU - Mattavelli, Laura
AU - Zoia, Chiara
AU - Tremolizzo, Lucio
AU - Ferri, Alberto
AU - Carrì, Maria Teresa
AU - Ferrarese, Carlo
PY - 2005/2
Y1 - 2005/2
N2 - Human neuroblastoma SH-SY5Y cells transfected with either familial amyotrophic lateral sclerosis-typical G93A mutant or wild-type copper/zinc superoxide dismutase were compared to untransfected cells in term of glutamate transport. Vmax of glutamate uptake was reduced in mutant cells, with no change in Km. No difference in EAAT1, EAAT2 and EAAT3 glutamate transporter mRNAs and immunoreactive proteins was found, suggesting that one or more transporters are functionally inactivated, possibly due to increased oxidative stress induced by the G93A mutation. Mutant cells showed a marked sensitivity to oxidants, resulting in a more pronounced reduction of glutamate uptake. Short-term antioxidant treatment did not reverse the impairment of glutamate uptake in G93A cells. Interestlingly, N-acetylcysteine was partially effective in preventing glutamate uptake reduction due to exogenous oxidative insults. Since the inhibition of the EAAT2 transporter subtype had no effect on glutamate re-uptake in this model, our study suggests an impaired function of the EAAT1/3 transporter subtypes, possibly due to oxidative inactivation, in the presence of mutant copper/zinc superoxide dismutase. Therefore, this model might prove to be a valuable tool to study the effects of mutant copper/zinc superoxide dismutase associated with amyotrophic lateral sclerosis on glutamate transport in neuronal cells, without the specific contribution of glial cells. These findings might lead to the identification of new therapeutic strategies aimed at preventing the damage associated with ALS.
AB - Human neuroblastoma SH-SY5Y cells transfected with either familial amyotrophic lateral sclerosis-typical G93A mutant or wild-type copper/zinc superoxide dismutase were compared to untransfected cells in term of glutamate transport. Vmax of glutamate uptake was reduced in mutant cells, with no change in Km. No difference in EAAT1, EAAT2 and EAAT3 glutamate transporter mRNAs and immunoreactive proteins was found, suggesting that one or more transporters are functionally inactivated, possibly due to increased oxidative stress induced by the G93A mutation. Mutant cells showed a marked sensitivity to oxidants, resulting in a more pronounced reduction of glutamate uptake. Short-term antioxidant treatment did not reverse the impairment of glutamate uptake in G93A cells. Interestlingly, N-acetylcysteine was partially effective in preventing glutamate uptake reduction due to exogenous oxidative insults. Since the inhibition of the EAAT2 transporter subtype had no effect on glutamate re-uptake in this model, our study suggests an impaired function of the EAAT1/3 transporter subtypes, possibly due to oxidative inactivation, in the presence of mutant copper/zinc superoxide dismutase. Therefore, this model might prove to be a valuable tool to study the effects of mutant copper/zinc superoxide dismutase associated with amyotrophic lateral sclerosis on glutamate transport in neuronal cells, without the specific contribution of glial cells. These findings might lead to the identification of new therapeutic strategies aimed at preventing the damage associated with ALS.
KW - Amyotrophic lateral sclerosis
KW - Antioxidants
KW - Copper/zinc superoxide dismutase
KW - Excitotoxicity
KW - Glutamate uptake
KW - Oxidative stress
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U2 - 10.1016/j.neuint.2004.10.002
DO - 10.1016/j.neuint.2004.10.002
M3 - Article
C2 - 15670639
AN - SCOPUS:12744268071
VL - 46
SP - 227
EP - 234
JO - Neurochemistry International
JF - Neurochemistry International
SN - 0197-0186
IS - 3
ER -