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Mitochondrial ROS Produced via Reverse Electron Transport Extend Animal Lifespan.

Scialò F, Sriram A, Fernández-Ayala D, Gubina N, Lõhmus M, Nelson G, Logan A, Cooper HM, Navas P, Enríquez JA, Murphy MP, Sanz A - Cell Metab. (2016)

Bottom Line: Here we show that the site of ROS production significantly contributes to their apparent dual nature.Furthermore, preventing ubiquinone reduction, through knockdown of PINK1, shortens lifespan and accelerates aging; phenotypes that are rescued by increasing reverse electron transport.These results illustrate that the source of a ROS signal is vital in determining its effects on cellular physiology and establish that manipulation of ubiquinone redox state is a valid strategy to delay aging.

View Article: PubMed Central - PubMed

Affiliation: Institute for Cell and Molecular Biosciences, Newcastle University Institute for Ageing, Newcastle University, Newcastle upon Tyne NE4 5PL, UK.

No MeSH data available.


Related in: MedlinePlus

NDI1 Increases ROS Production via Over-Reduction of CoQ(A) Representative images of dissected brains from indicated genotypes stained with MitoSOX.(B) Quantification of (A) (n = 5).(C) Survival curves for the indicated genotypes (n = 200).(D) Schematic diagram illustrating effects of expressing two different alternative respiratory enzymes on electron transport: (i) NDI1 generates ROS by over-reducing the CoQ pool; (ii) AOX reverts the effects of NDI1 by re-oxidizing the CoQ pool; (iii) decrease in the levels of CI can prevent reduction of CoQ and subsequent ROS production; (iv) ectopic expression of mtCAT reduces ROS levels without altering mitochondrial respiration or the redox state of CoQ.(E) Representative images of brains from the indicated genotypes stained with MitoSOX.(F) Quantification of (E) (n = 5).(G) Survival curves for the indicated genotypes (n = 160).(H) In vivo ROS measurements from indicated genotypes in brains dissected from flies expressing a mitochondrially localized redox-sensitive GFP-based reporter.(I) Quantification of (H) (n = 5–7).(J) Quantification of brains dissected from flies of the indicated genotypes stained with MitoSOX (n = 5).(K) Survival curves for the indicated genotypes (n = 200).(L) Diagram illustrating using metabolic poisons to dissect ROS production: rotenone (ROT), carbonyl cyanide-p-trifluoromethoxyphenylhydrazone (FCCP), or myxothiazol (MYX). Green dashed arrows indicate the possible flow of electrons following CoQ reduction.(M) Quantification of brains dissected from NDI1 flies fed with metabolic poisons, stained with MitoSOX (n = 4).Values shown represent means ± SEM of at least 3 biological replicates, unless otherwise stated.See also Figure S2 and Table S1 for statistical analysis of survival curves.
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fig2: NDI1 Increases ROS Production via Over-Reduction of CoQ(A) Representative images of dissected brains from indicated genotypes stained with MitoSOX.(B) Quantification of (A) (n = 5).(C) Survival curves for the indicated genotypes (n = 200).(D) Schematic diagram illustrating effects of expressing two different alternative respiratory enzymes on electron transport: (i) NDI1 generates ROS by over-reducing the CoQ pool; (ii) AOX reverts the effects of NDI1 by re-oxidizing the CoQ pool; (iii) decrease in the levels of CI can prevent reduction of CoQ and subsequent ROS production; (iv) ectopic expression of mtCAT reduces ROS levels without altering mitochondrial respiration or the redox state of CoQ.(E) Representative images of brains from the indicated genotypes stained with MitoSOX.(F) Quantification of (E) (n = 5).(G) Survival curves for the indicated genotypes (n = 160).(H) In vivo ROS measurements from indicated genotypes in brains dissected from flies expressing a mitochondrially localized redox-sensitive GFP-based reporter.(I) Quantification of (H) (n = 5–7).(J) Quantification of brains dissected from flies of the indicated genotypes stained with MitoSOX (n = 5).(K) Survival curves for the indicated genotypes (n = 200).(L) Diagram illustrating using metabolic poisons to dissect ROS production: rotenone (ROT), carbonyl cyanide-p-trifluoromethoxyphenylhydrazone (FCCP), or myxothiazol (MYX). Green dashed arrows indicate the possible flow of electrons following CoQ reduction.(M) Quantification of brains dissected from NDI1 flies fed with metabolic poisons, stained with MitoSOX (n = 4).Values shown represent means ± SEM of at least 3 biological replicates, unless otherwise stated.See also Figure S2 and Table S1 for statistical analysis of survival curves.

Mentions: Based on our previous results, we hypothesized that decreasing ROS and compensating for a loss in CI respiration would extend lifespan. We and others have previously reported that allotopic expression of NDI1 decreases ROS in mitochondria isolated from old individuals (Sanz et al., 2010). Surprisingly, measurement of ROS levels using MitoSOX, H2DCF, and mtORP1-roGPF revealed in fly brains a NDI1-mediated increase in ROS that was partially abolished by AOX expression (Figures 2A, 2B, and S2B). Neither NDI1 nor AOX had any detectable effect on respiration alone (Figure S2C). Strikingly, the increase in ROS elicited by NDI1 was similar to that caused by feeding flies with a dose of rotenone able to significantly inhibit CI (Figures S2D–S2F). AOX expression completely abolished lifespan extension conferred by NDI1 (Figure 2C), suggesting that NDI1 lifespan extension is dependent on over-reduction of the ETC and consequently increased ROS levels. Expression of AOX alone had a mild effect on wild-type ROS production (Figures 2A, 2B, and S2B) and did not shorten lifespan (Figure 2C).


Mitochondrial ROS Produced via Reverse Electron Transport Extend Animal Lifespan.

Scialò F, Sriram A, Fernández-Ayala D, Gubina N, Lõhmus M, Nelson G, Logan A, Cooper HM, Navas P, Enríquez JA, Murphy MP, Sanz A - Cell Metab. (2016)

NDI1 Increases ROS Production via Over-Reduction of CoQ(A) Representative images of dissected brains from indicated genotypes stained with MitoSOX.(B) Quantification of (A) (n = 5).(C) Survival curves for the indicated genotypes (n = 200).(D) Schematic diagram illustrating effects of expressing two different alternative respiratory enzymes on electron transport: (i) NDI1 generates ROS by over-reducing the CoQ pool; (ii) AOX reverts the effects of NDI1 by re-oxidizing the CoQ pool; (iii) decrease in the levels of CI can prevent reduction of CoQ and subsequent ROS production; (iv) ectopic expression of mtCAT reduces ROS levels without altering mitochondrial respiration or the redox state of CoQ.(E) Representative images of brains from the indicated genotypes stained with MitoSOX.(F) Quantification of (E) (n = 5).(G) Survival curves for the indicated genotypes (n = 160).(H) In vivo ROS measurements from indicated genotypes in brains dissected from flies expressing a mitochondrially localized redox-sensitive GFP-based reporter.(I) Quantification of (H) (n = 5–7).(J) Quantification of brains dissected from flies of the indicated genotypes stained with MitoSOX (n = 5).(K) Survival curves for the indicated genotypes (n = 200).(L) Diagram illustrating using metabolic poisons to dissect ROS production: rotenone (ROT), carbonyl cyanide-p-trifluoromethoxyphenylhydrazone (FCCP), or myxothiazol (MYX). Green dashed arrows indicate the possible flow of electrons following CoQ reduction.(M) Quantification of brains dissected from NDI1 flies fed with metabolic poisons, stained with MitoSOX (n = 4).Values shown represent means ± SEM of at least 3 biological replicates, unless otherwise stated.See also Figure S2 and Table S1 for statistical analysis of survival curves.
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Related In: Results  -  Collection

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fig2: NDI1 Increases ROS Production via Over-Reduction of CoQ(A) Representative images of dissected brains from indicated genotypes stained with MitoSOX.(B) Quantification of (A) (n = 5).(C) Survival curves for the indicated genotypes (n = 200).(D) Schematic diagram illustrating effects of expressing two different alternative respiratory enzymes on electron transport: (i) NDI1 generates ROS by over-reducing the CoQ pool; (ii) AOX reverts the effects of NDI1 by re-oxidizing the CoQ pool; (iii) decrease in the levels of CI can prevent reduction of CoQ and subsequent ROS production; (iv) ectopic expression of mtCAT reduces ROS levels without altering mitochondrial respiration or the redox state of CoQ.(E) Representative images of brains from the indicated genotypes stained with MitoSOX.(F) Quantification of (E) (n = 5).(G) Survival curves for the indicated genotypes (n = 160).(H) In vivo ROS measurements from indicated genotypes in brains dissected from flies expressing a mitochondrially localized redox-sensitive GFP-based reporter.(I) Quantification of (H) (n = 5–7).(J) Quantification of brains dissected from flies of the indicated genotypes stained with MitoSOX (n = 5).(K) Survival curves for the indicated genotypes (n = 200).(L) Diagram illustrating using metabolic poisons to dissect ROS production: rotenone (ROT), carbonyl cyanide-p-trifluoromethoxyphenylhydrazone (FCCP), or myxothiazol (MYX). Green dashed arrows indicate the possible flow of electrons following CoQ reduction.(M) Quantification of brains dissected from NDI1 flies fed with metabolic poisons, stained with MitoSOX (n = 4).Values shown represent means ± SEM of at least 3 biological replicates, unless otherwise stated.See also Figure S2 and Table S1 for statistical analysis of survival curves.
Mentions: Based on our previous results, we hypothesized that decreasing ROS and compensating for a loss in CI respiration would extend lifespan. We and others have previously reported that allotopic expression of NDI1 decreases ROS in mitochondria isolated from old individuals (Sanz et al., 2010). Surprisingly, measurement of ROS levels using MitoSOX, H2DCF, and mtORP1-roGPF revealed in fly brains a NDI1-mediated increase in ROS that was partially abolished by AOX expression (Figures 2A, 2B, and S2B). Neither NDI1 nor AOX had any detectable effect on respiration alone (Figure S2C). Strikingly, the increase in ROS elicited by NDI1 was similar to that caused by feeding flies with a dose of rotenone able to significantly inhibit CI (Figures S2D–S2F). AOX expression completely abolished lifespan extension conferred by NDI1 (Figure 2C), suggesting that NDI1 lifespan extension is dependent on over-reduction of the ETC and consequently increased ROS levels. Expression of AOX alone had a mild effect on wild-type ROS production (Figures 2A, 2B, and S2B) and did not shorten lifespan (Figure 2C).

Bottom Line: Here we show that the site of ROS production significantly contributes to their apparent dual nature.Furthermore, preventing ubiquinone reduction, through knockdown of PINK1, shortens lifespan and accelerates aging; phenotypes that are rescued by increasing reverse electron transport.These results illustrate that the source of a ROS signal is vital in determining its effects on cellular physiology and establish that manipulation of ubiquinone redox state is a valid strategy to delay aging.

View Article: PubMed Central - PubMed

Affiliation: Institute for Cell and Molecular Biosciences, Newcastle University Institute for Ageing, Newcastle University, Newcastle upon Tyne NE4 5PL, UK.

No MeSH data available.


Related in: MedlinePlus