SSADH Variants Increase Susceptibility of U87 Cells to Mitochondrial Pro-Oxidant Insult

International Journal of Molecular Sciences

ConcettaRosa Capo¹  Daniele Lettieri-Barbato¹  Luisa Rossi¹  Alessandra Vitaliti¹  Katia Aquilano¹  Patrizia Malaspina¹  Giovanna Menduti¹ 

[1] Department of Biology, University of Rome Tor Vergata, 00133 Rome, Italy;

关键词: GABA;    SSADH;    ALDH5A1;    SSA;    4-HNE;    paraquat;   

DOI  :  10.3390/ijms21124374

来源: DOAJ

【 摘 要 】

Succinate semialdehyde dehydrogenase (SSADH) is a mitochondrial enzyme, encoded by ALDH5A1, mainly involved in γ-aminobutyric acid (GABA) catabolism and energy supply of neuronal cells, possibly contributing to antioxidant defense. This study aimed to further investigate the antioxidant role of SSADH, and to verify if common SNPs of ALDH5A1 may affect SSADH activity, stability, and mitochondrial function. In this study, we used U87 glioblastoma cells as they represent a glial cell line. These cells were transiently transfected with a cDNA construct simultaneously harboring three SNPs encoding for a triple mutant (TM) SSADH protein (p.G36R/p.H180Y/p.P182L) or with wild type (WT) cDNA. SSADH activity and protein level were measured. Cell viability, lipid peroxidation, mitochondrial morphology, membrane potential (ΔΨ), and protein markers of mitochondrial stress were evaluated upon Paraquat treatment, in TM and WT transfected cells. TM transfected cells show lower SSADH protein content and activity, fragmented mitochondria, higher levels of peroxidized lipids, and altered ΔΨ than WT transfected cells. Upon Paraquat treatment, TM cells show higher cell death, lipid peroxidation, 4-HNE protein adducts, and lower ΔΨ, than WT transfected cells. These results reinforce the hypothesis that SSADH contributes to cellular antioxidant defense; furthermore, common SNPs may produce unstable, less active SSADH, which could per se negatively affect mitochondrial function and, under oxidative stress conditions, fail to protect mitochondria.

【 授权许可】

Unknown