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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

Re-Establishing the Redox State of CoQ Prevents Age-Related Pathology(A) PINK1 and Parkin levels in wild-type flies during aging.(B) Quantification of (A).(C) Representative images and quantification of dissected fly brains stained with MitoSOX (quantification n = 7).(D) Mitochondrial respiration in flies of the indicated genotypes.(E) CI, CII, and aconitase activities in flies of the indicated genotypes (n = 4–8).(F) Locomotive activity and flying time in flies of the indicated genotypes (n = 13).(G) Survival curves for the indicated genotypes (n = 160).(H) Mitochondrial respiration in flies of the indicated genotypes (n = 5).(I) Locomotive activity and flying time in flies of the indicated genotypes (n = 6).(J) Survival curves for the indicated genotypes (n = 160).Values shown represent means ± SEM of at least three biological replicates, unless otherwise stated. −/+ indicates absence/presence of 500 μM RU-486 during adulthood. See also Figure S4 and Table S1 for statistical analysis of survival curves.
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fig4: Re-Establishing the Redox State of CoQ Prevents Age-Related Pathology(A) PINK1 and Parkin levels in wild-type flies during aging.(B) Quantification of (A).(C) Representative images and quantification of dissected fly brains stained with MitoSOX (quantification n = 7).(D) Mitochondrial respiration in flies of the indicated genotypes.(E) CI, CII, and aconitase activities in flies of the indicated genotypes (n = 4–8).(F) Locomotive activity and flying time in flies of the indicated genotypes (n = 13).(G) Survival curves for the indicated genotypes (n = 160).(H) Mitochondrial respiration in flies of the indicated genotypes (n = 5).(I) Locomotive activity and flying time in flies of the indicated genotypes (n = 6).(J) Survival curves for the indicated genotypes (n = 160).Values shown represent means ± SEM of at least three biological replicates, unless otherwise stated. −/+ indicates absence/presence of 500 μM RU-486 during adulthood. See also Figure S4 and Table S1 for statistical analysis of survival curves.

Mentions: In Figure 1, we demonstrated that mitochondrial quality was decreased in aged flies. Interestingly, we also found that levels of PINK1 and Parkin decreased in parallel over time (Figures 4A and 4B). Experimental manipulation of PINK1 and Parkin levels has previously been shown to alter Drosophila lifespan (Rana et al., 2013, Todd and Staveley, 2012). Decreases in PINK1 activity have been related to a loss of CI activity (Morais et al., 2014), while Parkin loss of function mutations cause the accumulation of aberrant mitochondria (Greene et al., 2003). Strikingly, decreases in PINK1 and Parkin levels (Figures 4A and 4B) preceded the decline in respiration observed in old flies (Figure 1D). We hypothesized that this may contribute to the mitochondrial dysfunction that occurs with age. It has been recently shown that PINK1 is required for reduction of CoQ by CI via phosphorylation of NDUFA10 (Morais et al., 2014), although this was not confirmed by a later report (Pogson et al., 2014). Since PINK1 protein levels decrease with age, we hypothesized that this decrease could be responsible for the decline in CI-respiration. To test the relevance of CoQ-mediated ROS signaling in a more physiological context, we used the inducible GeneSwitch system to drive expression of an RNAi construct against PINK1 specifically in adult flies (PINK1 > daGS flies, Figure S4A). PINK1 knockdown did not increase ROS levels (Figures 4C and S4B); however, we did observe a significant decrease in CI-linked respiration (Figure 4D) and NADH:DQ CI activity, but not NADH:HAR activity (Figure 4E) or CI protein levels (Figure S4C), showing that reduction of CoQ by CI was impaired, as was observed in SOD2 knockdown flies (Figures 3D and 3E) and 50-d-old wild-type flies (Figures 1D and 1E). Furthermore, PINK1 knockdown flies displayed decreased mobility, time spent flying, and lifespan compared to controls (Figures 4F and 4G).


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)

Re-Establishing the Redox State of CoQ Prevents Age-Related Pathology(A) PINK1 and Parkin levels in wild-type flies during aging.(B) Quantification of (A).(C) Representative images and quantification of dissected fly brains stained with MitoSOX (quantification n = 7).(D) Mitochondrial respiration in flies of the indicated genotypes.(E) CI, CII, and aconitase activities in flies of the indicated genotypes (n = 4–8).(F) Locomotive activity and flying time in flies of the indicated genotypes (n = 13).(G) Survival curves for the indicated genotypes (n = 160).(H) Mitochondrial respiration in flies of the indicated genotypes (n = 5).(I) Locomotive activity and flying time in flies of the indicated genotypes (n = 6).(J) Survival curves for the indicated genotypes (n = 160).Values shown represent means ± SEM of at least three biological replicates, unless otherwise stated. −/+ indicates absence/presence of 500 μM RU-486 during adulthood. See also Figure S4 and Table S1 for statistical analysis of survival curves.
© Copyright Policy - CC BY-NC-ND
Related In: Results  -  Collection

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Show All Figures
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fig4: Re-Establishing the Redox State of CoQ Prevents Age-Related Pathology(A) PINK1 and Parkin levels in wild-type flies during aging.(B) Quantification of (A).(C) Representative images and quantification of dissected fly brains stained with MitoSOX (quantification n = 7).(D) Mitochondrial respiration in flies of the indicated genotypes.(E) CI, CII, and aconitase activities in flies of the indicated genotypes (n = 4–8).(F) Locomotive activity and flying time in flies of the indicated genotypes (n = 13).(G) Survival curves for the indicated genotypes (n = 160).(H) Mitochondrial respiration in flies of the indicated genotypes (n = 5).(I) Locomotive activity and flying time in flies of the indicated genotypes (n = 6).(J) Survival curves for the indicated genotypes (n = 160).Values shown represent means ± SEM of at least three biological replicates, unless otherwise stated. −/+ indicates absence/presence of 500 μM RU-486 during adulthood. See also Figure S4 and Table S1 for statistical analysis of survival curves.
Mentions: In Figure 1, we demonstrated that mitochondrial quality was decreased in aged flies. Interestingly, we also found that levels of PINK1 and Parkin decreased in parallel over time (Figures 4A and 4B). Experimental manipulation of PINK1 and Parkin levels has previously been shown to alter Drosophila lifespan (Rana et al., 2013, Todd and Staveley, 2012). Decreases in PINK1 activity have been related to a loss of CI activity (Morais et al., 2014), while Parkin loss of function mutations cause the accumulation of aberrant mitochondria (Greene et al., 2003). Strikingly, decreases in PINK1 and Parkin levels (Figures 4A and 4B) preceded the decline in respiration observed in old flies (Figure 1D). We hypothesized that this may contribute to the mitochondrial dysfunction that occurs with age. It has been recently shown that PINK1 is required for reduction of CoQ by CI via phosphorylation of NDUFA10 (Morais et al., 2014), although this was not confirmed by a later report (Pogson et al., 2014). Since PINK1 protein levels decrease with age, we hypothesized that this decrease could be responsible for the decline in CI-respiration. To test the relevance of CoQ-mediated ROS signaling in a more physiological context, we used the inducible GeneSwitch system to drive expression of an RNAi construct against PINK1 specifically in adult flies (PINK1 > daGS flies, Figure S4A). PINK1 knockdown did not increase ROS levels (Figures 4C and S4B); however, we did observe a significant decrease in CI-linked respiration (Figure 4D) and NADH:DQ CI activity, but not NADH:HAR activity (Figure 4E) or CI protein levels (Figure S4C), showing that reduction of CoQ by CI was impaired, as was observed in SOD2 knockdown flies (Figures 3D and 3E) and 50-d-old wild-type flies (Figures 1D and 1E). Furthermore, PINK1 knockdown flies displayed decreased mobility, time spent flying, and lifespan compared to controls (Figures 4F and 4G).

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