Oxidative stress and aging reduce COX I RNA and cytochrome oxidase activity in Drosophila.
Free Radic Biol Med
; 25(6): 740-7, 1998 Oct.
Article
en En
| MEDLINE
| ID: mdl-9801075
ABSTRACT
Drosophila melanogaster displays an age-associated increase in oxidative damage and a decrease in mitochondrial transcripts. To determine if these changes result in energy production deficiencies, we measured the electron transport system (ETS) enzyme activity, and ATP levels with age. No statistically significant influences of age on activities of complexes I and II or citrate synthase were observed. In contrast, from 2 to 45 days post-eclosion, declines were found in complex IV cytochrome c oxidase activity (COX, 40% decline) and ATP abundance (15%), while lipid peroxidation increased 71%. We next examined flies that were either genetically or chemically oxidatively stressed to determine the effect on levels of mitochondrial-encoded cytochrome oxidase I RNA (coxI) and COX activity. A catalase null mutant line had 48% of coxI RNA compared to the wild type. In Cu/Zn superoxide dismutase (cSOD) null flies, the rate of coxI RNA decline was greater than in controls. CoxI RNA also declined with increasing hydrogen peroxide (H2O2) treatment, which was reflected in reduced cytochrome c oxidase (COX) activity. These results show that oxidative stress is closely associated with reductions in mitochondrial transcript levels and support the hypothesis that oxidative stress may contribute to mitochondrial dysfunction and aging in D. melanogaster.
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Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Envejecimiento
/
ARN Mensajero
/
Prostaglandina-Endoperóxido Sintasas
/
Complejo IV de Transporte de Electrones
/
Estrés Oxidativo
/
Drosophila
Límite:
Animals
Idioma:
En
Revista:
Free Radic Biol Med
Asunto de la revista:
BIOQUIMICA
/
MEDICINA
Año:
1998
Tipo del documento:
Article
País de afiliación:
Estados Unidos