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Heterologous ferredoxin reductase and flavodoxin protect Cos-7 cells from oxidative stress.

ABSTRACT: BACKGROUND: Ferredoxin-NADP(H) reductase (FNR) from Pisum sativum and Flavodoxin (Fld) from Anabaena PCC 7119 have been reported to protect a variety of cells and organisms from oxidative insults. In this work, these two proteins were expressed in mitochondria of Cos-7 cells and tested for their efficacy to protect these cells from oxidative stress in vitro. PRINCIPAL FINDINGS: Cos-7/pFNR and Cos-7/pFld cell lines expressing FNR and Fld, respectively, showed a significantly higher resistance to 24 h exposure to 300-600 µM hydrogen peroxide measured by LDH retention, MTT reduction, malondialdehyde (MDA) levels and lipid peroxide (LPO; FOX assay) levels. However, FNR and Fld did not exhibit any protection at shorter incubation times (2 h and 4 h) to 4 mM hydrogen peroxide or to a 48 h exposure to 300 µM methyl viologen. We found enhanced methyl viologen damage exerted by FNR that may be due to depletion of NADPH pools through NADPH-MV diaphorase activity as previously observed for other overexpressed enzymes. SIGNIFICANCE: The results presented are a first report of antioxidant function of these heterologous enzymes of vegetal and cyanobacterial origin in mammalian cells.

SUBMITTER: Mediavilla MG

PROVIDER: S-EPMC2957446 | biostudies-literature | 2010

REPOSITORIES: biostudies-literature

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Heterologous ferredoxin reductase and flavodoxin protect Cos-7 cells from oxidative stress.

Mediavilla María G MG Di Venanzio Gisela A GA Guibert Edgardo E EE Tiribelli Claudio C

PloS one 20101019 10

<h4>Background</h4>Ferredoxin-NADP(H) reductase (FNR) from Pisum sativum and Flavodoxin (Fld) from Anabaena PCC 7119 have been reported to protect a variety of cells and organisms from oxidative insults. In this work, these two proteins were expressed in mitochondria of Cos-7 cells and tested for their efficacy to protect these cells from oxidative stress in vitro.<h4>Principal findings</h4>Cos-7/pFNR and Cos-7/pFld cell lines expressing FNR and Fld, respectively, showed a significantly higher r ...[more]

PMID: 20976072

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Dataset Information

Heterologous ferredoxin reductase and flavodoxin protect Cos-7 cells from oxidative stress.

Publications

Heterologous ferredoxin reductase and flavodoxin protect Cos-7 cells from oxidative stress.

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