TY - JOUR
T1 - Actin Glutathionylation Increases in Fibroblasts of Patients with Friedreich's Ataxia
T2 - A potential role in the pathogenesis of the disease
AU - Pastore, Anna
AU - Tozzi, Giulia
AU - Gaeta, Laura Maria
AU - Bertini, Enrico
AU - Serafini, Valentina
AU - Di Cesare, Silvia
AU - Bonetto, Valentina
AU - Casoni, Filippo
AU - Carrozzo, Rosalba
AU - Federici, Giorgio
AU - Piemonte, Fiorella
PY - 2003/10/24
Y1 - 2003/10/24
N2 - Increasing evidence suggests that iron-mediated oxidative stress might underlie the development of neurodegeneration in Friedreich's ataxia (FRDA), an autosomal recessive ataxia caused by decreased expression of frataxin, a protein implicated in iron metabolism. In this study, we demonstrate that, in fibroblasts of patients with FRDA, the cellular redox equilibrium is shifted toward more protein-bound glutathione. Furthermore, we found that actin is glutathionylated, probably as a result of the accumulation of reactive oxygen species, generated by iron overload in the disease. Indeed, high-pressure liquid chromatography analysis of control fibroblasts in vivo treated with FeSO4 showed a significant increase in the protein-bound/free GSH ratio, and Western blot analysis indicated a relevant rise in glutathionylation. Actin glutathionylation contributes to impaired microfilament organization in FRDA fibroblasts. Rhodamine phalloidin staining revealed a disarray of actin filaments and a reduced signal of F-actin fluorescence. The same hematoxylin/eosin-stained cells showed abnormalities in size and shape. When we treated FRDA fibroblasts with reduced glutathione, we obtained a complete rescue of cytoskeletal abnormalities and cell viability. Thus, we conclude that oxidative stress may induce actin glutathionylation and impairment of cytoskeletal functions in FRDA fibroblasts.
AB - Increasing evidence suggests that iron-mediated oxidative stress might underlie the development of neurodegeneration in Friedreich's ataxia (FRDA), an autosomal recessive ataxia caused by decreased expression of frataxin, a protein implicated in iron metabolism. In this study, we demonstrate that, in fibroblasts of patients with FRDA, the cellular redox equilibrium is shifted toward more protein-bound glutathione. Furthermore, we found that actin is glutathionylated, probably as a result of the accumulation of reactive oxygen species, generated by iron overload in the disease. Indeed, high-pressure liquid chromatography analysis of control fibroblasts in vivo treated with FeSO4 showed a significant increase in the protein-bound/free GSH ratio, and Western blot analysis indicated a relevant rise in glutathionylation. Actin glutathionylation contributes to impaired microfilament organization in FRDA fibroblasts. Rhodamine phalloidin staining revealed a disarray of actin filaments and a reduced signal of F-actin fluorescence. The same hematoxylin/eosin-stained cells showed abnormalities in size and shape. When we treated FRDA fibroblasts with reduced glutathione, we obtained a complete rescue of cytoskeletal abnormalities and cell viability. Thus, we conclude that oxidative stress may induce actin glutathionylation and impairment of cytoskeletal functions in FRDA fibroblasts.
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U2 - 10.1074/jbc.M301872200
DO - 10.1074/jbc.M301872200
M3 - Article
C2 - 12915401
AN - SCOPUS:0142211205
VL - 278
SP - 42588
EP - 42595
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 43
ER -