Coenzyme Q10 protects SHSY5Y neuronal cells from beta amyloid toxicity and oxygen-glucose deprivation by inhibiting the opening of the mitochondrial permeability transition pore

Abstract

Coenzyme Q10 (CoQ10) is an essential biological cofactor which increases brain mitochondrial concentration and exerts neuroprotective effects. In the present study, we exposed SHSY5Y neuroblastoma cells to neurotoxic beta amyloid peptides (Aβ) and oxygen glucose deprivation (OGD) to investigate the neuroprotective effect of 10 μM CoQ10 by measuring (i) cell viability by the MTT assay, (ii) opening of the mitochondrial permeability transition pore via the fluorescence intensity of calcein-AM, and (iii) superoxide anion concentration by hydroethidine. Cell viability (mean ± S.E.M.) was 55.5 ± 0.8% in the group exposed to Aβ + OGD, a value lower than that in the Aβ or OGD group alone (P < 0.01). CoQ10 had no neuroprotective effect on cell death induced by either Aβ or OGD, but increased cell survival in the Aβ + OGD group to 57.3 ± 1.7%, which was higher than in the group treated with vehicle (P < 0.05). The neuroprotective effect of CoQ10 was blocked by administration of 20 μM atractyloside. Pore opening and superoxide anion concentration were increased in the Aβ + OGD group relative to sham control (P < 0.01), and were attenuated to the sham level (P > 0.05) when CoQ10 was administered. Our results demonstrate that CoQ10 protects neuronal cells against Aβ neurotoxicity together with OGD by inhibiting the opening of the pore and reducing the concentration of superoxide anion. © 2005 - IOS Press and the authors. All rights reserved.