Abstract
Carbon monoxide (CO), produced during the degradation of heme by the enzyme heme oxygenase, is an important signaling mediator in mammalian cells. Here we show that precise delivery of CO to isolated heart mitochondria using a water-soluble CO-releasing molecule (CORM-3) uncouples respiration. Addition of low-micromolar concentrations of CORM-3 (1-20 μM), but not an inactive compound that does not release CO, significantly increased mitochondrial oxygen consumption rate (State 2 respiration) in a concentration-dependent manner. In contrast, higher concentrations of CORM-3 (100 μM) suppressed ADP-dependent respiration through inhibition of cytochrome c oxidase. The uncoupling effect mediated by CORM-3 was inhibited in the presence of the CO scavenger myoglobin. Moreover, this effect was associated with a gradual decrease in membrane potential (ψ) over time and was partially reversed by malonate, an inhibitor of complex II activity. Similarly, inhibition of uncoupling proteins or blockade of adenine nucleotide transporter attenuated the effect of CORM-3 on both State 2 respiration and Δψ. Hydrogen peroxide (H 2O2) produced by mitochondria respiring from complex I-linked substrates (pyruvate/malate) was increased by CORM-3. However, respiration initiated via complex II using succinate resulted in a fivefold increase in H2O2 production and this effect was significantly inhibited by CORM-3. These findings disclose a counterintuitive action of CORM-3 suggesting that CO at low levels acts as an important regulator of mitochondrial respiration.
| Original language | English |
|---|---|
| Pages (from-to) | 1556-1564 |
| Number of pages | 9 |
| Journal | Free Radical Biology and Medicine |
| Volume | 50 |
| Issue number | 11 |
| DOIs | |
| Publication status | Published - Jun 1 2011 |
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Keywords
- Carbon monoxide
- CO-releasing molecules
- Free radicals
- Mitochondrial respiration
- Reactive oxygen species
- Uncoupling agents
ASJC Scopus subject areas
- Biochemistry
- Physiology (medical)
Cite this
A carbon monoxide-releasing molecule (CORM-3) uncouples mitochondrial respiration and modulates the production of reactive oxygen species. / Lo Iacono, Luisa; Boczkowski, Jorge; Zini, Roland; Salouage, Issam; Berdeaux, Alain; Motterlini, Roberto; Morin, Didier.
In: Free Radical Biology and Medicine, Vol. 50, No. 11, 01.06.2011, p. 1556-1564.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - A carbon monoxide-releasing molecule (CORM-3) uncouples mitochondrial respiration and modulates the production of reactive oxygen species
AU - Lo Iacono, Luisa
AU - Boczkowski, Jorge
AU - Zini, Roland
AU - Salouage, Issam
AU - Berdeaux, Alain
AU - Motterlini, Roberto
AU - Morin, Didier
PY - 2011/6/1
Y1 - 2011/6/1
N2 - Carbon monoxide (CO), produced during the degradation of heme by the enzyme heme oxygenase, is an important signaling mediator in mammalian cells. Here we show that precise delivery of CO to isolated heart mitochondria using a water-soluble CO-releasing molecule (CORM-3) uncouples respiration. Addition of low-micromolar concentrations of CORM-3 (1-20 μM), but not an inactive compound that does not release CO, significantly increased mitochondrial oxygen consumption rate (State 2 respiration) in a concentration-dependent manner. In contrast, higher concentrations of CORM-3 (100 μM) suppressed ADP-dependent respiration through inhibition of cytochrome c oxidase. The uncoupling effect mediated by CORM-3 was inhibited in the presence of the CO scavenger myoglobin. Moreover, this effect was associated with a gradual decrease in membrane potential (ψ) over time and was partially reversed by malonate, an inhibitor of complex II activity. Similarly, inhibition of uncoupling proteins or blockade of adenine nucleotide transporter attenuated the effect of CORM-3 on both State 2 respiration and Δψ. Hydrogen peroxide (H 2O2) produced by mitochondria respiring from complex I-linked substrates (pyruvate/malate) was increased by CORM-3. However, respiration initiated via complex II using succinate resulted in a fivefold increase in H2O2 production and this effect was significantly inhibited by CORM-3. These findings disclose a counterintuitive action of CORM-3 suggesting that CO at low levels acts as an important regulator of mitochondrial respiration.
AB - Carbon monoxide (CO), produced during the degradation of heme by the enzyme heme oxygenase, is an important signaling mediator in mammalian cells. Here we show that precise delivery of CO to isolated heart mitochondria using a water-soluble CO-releasing molecule (CORM-3) uncouples respiration. Addition of low-micromolar concentrations of CORM-3 (1-20 μM), but not an inactive compound that does not release CO, significantly increased mitochondrial oxygen consumption rate (State 2 respiration) in a concentration-dependent manner. In contrast, higher concentrations of CORM-3 (100 μM) suppressed ADP-dependent respiration through inhibition of cytochrome c oxidase. The uncoupling effect mediated by CORM-3 was inhibited in the presence of the CO scavenger myoglobin. Moreover, this effect was associated with a gradual decrease in membrane potential (ψ) over time and was partially reversed by malonate, an inhibitor of complex II activity. Similarly, inhibition of uncoupling proteins or blockade of adenine nucleotide transporter attenuated the effect of CORM-3 on both State 2 respiration and Δψ. Hydrogen peroxide (H 2O2) produced by mitochondria respiring from complex I-linked substrates (pyruvate/malate) was increased by CORM-3. However, respiration initiated via complex II using succinate resulted in a fivefold increase in H2O2 production and this effect was significantly inhibited by CORM-3. These findings disclose a counterintuitive action of CORM-3 suggesting that CO at low levels acts as an important regulator of mitochondrial respiration.
KW - Carbon monoxide
KW - CO-releasing molecules
KW - Free radicals
KW - Mitochondrial respiration
KW - Reactive oxygen species
KW - Uncoupling agents
UR - http://www.scopus.com/inward/record.url?scp=79955598078&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79955598078&partnerID=8YFLogxK
U2 - 10.1016/j.freeradbiomed.2011.02.033
DO - 10.1016/j.freeradbiomed.2011.02.033
M3 - Article
C2 - 21382478
AN - SCOPUS:79955598078
VL - 50
SP - 1556
EP - 1564
JO - Free Radical Biology and Medicine
JF - Free Radical Biology and Medicine
SN - 0891-5849
IS - 11
ER -