Abstract
It has been reported recently (Tretter et al., 2007b) that in isolated guinea pig brain mitochondria supported by α-glycerophosphate (α-GP) reactive oxygen species (ROS) are produced through the reverse electron transport (RET) in the respiratory chain and by α-glycerophosphate dehydrogenase (α-GPDH). We studied the effect of calcium on the generation of H2O2 as measured by the Amplex Red fluorescent assay in this model. H2O2 production in α-GP-supported mitochondria was increased significantly in the presence of 100, 250, and 500 nM Ca2+, respectively. In addition, Ca2+ enhanced the membrane potential, the rate of oxygen consumption, and the NAD(P)H autofluorescence in these mitochondria. Direct measurement of α-GPDH activity showed that Ca2+ stimulated the enzyme by decreasing the Km for α-GR In those mitochondria where RET was eliminated by the Complex I inhibitor rotenone (2 μM) or due to depolarization by ADP (1 mM), the rate of H2O2 formation was smaller and the stimulation of H 2O2 generation by Ca2+ was prevented partly, but the stimulatory effect of Ca2+ was still significant. These data indicate that in α-GP-supported mitochondria activation of α-GPDH by Ca2+ leads to an accelerated RET-mediated ROS generation as well as to a stimulated ROS production by α-GPDH.
| Original language | English |
|---|---|
| Pages (from-to) | 3471-3479 |
| Number of pages | 9 |
| Journal | Journal of Neuroscience Research |
| Volume | 85 |
| Issue number | 15 |
| DOIs | |
| Publication status | Published - nov. 15 2007 |
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ASJC Scopus subject areas
- Neuroscience(all)
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Stimulation of H2O2 generation by calcium in brain mitochondria respiring on α-glycerophosphate. / Tretter, L.; Takacs, Katalin; Kövér, Kinga; Ádám-Vizi, V.
In: Journal of Neuroscience Research, Vol. 85, No. 15, 15.11.2007, p. 3471-3479.Research output: Article
}
TY - JOUR
T1 - Stimulation of H2O2 generation by calcium in brain mitochondria respiring on α-glycerophosphate
AU - Tretter, L.
AU - Takacs, Katalin
AU - Kövér, Kinga
AU - Ádám-Vizi, V.
PY - 2007/11/15
Y1 - 2007/11/15
N2 - It has been reported recently (Tretter et al., 2007b) that in isolated guinea pig brain mitochondria supported by α-glycerophosphate (α-GP) reactive oxygen species (ROS) are produced through the reverse electron transport (RET) in the respiratory chain and by α-glycerophosphate dehydrogenase (α-GPDH). We studied the effect of calcium on the generation of H2O2 as measured by the Amplex Red fluorescent assay in this model. H2O2 production in α-GP-supported mitochondria was increased significantly in the presence of 100, 250, and 500 nM Ca2+, respectively. In addition, Ca2+ enhanced the membrane potential, the rate of oxygen consumption, and the NAD(P)H autofluorescence in these mitochondria. Direct measurement of α-GPDH activity showed that Ca2+ stimulated the enzyme by decreasing the Km for α-GR In those mitochondria where RET was eliminated by the Complex I inhibitor rotenone (2 μM) or due to depolarization by ADP (1 mM), the rate of H2O2 formation was smaller and the stimulation of H 2O2 generation by Ca2+ was prevented partly, but the stimulatory effect of Ca2+ was still significant. These data indicate that in α-GP-supported mitochondria activation of α-GPDH by Ca2+ leads to an accelerated RET-mediated ROS generation as well as to a stimulated ROS production by α-GPDH.
AB - It has been reported recently (Tretter et al., 2007b) that in isolated guinea pig brain mitochondria supported by α-glycerophosphate (α-GP) reactive oxygen species (ROS) are produced through the reverse electron transport (RET) in the respiratory chain and by α-glycerophosphate dehydrogenase (α-GPDH). We studied the effect of calcium on the generation of H2O2 as measured by the Amplex Red fluorescent assay in this model. H2O2 production in α-GP-supported mitochondria was increased significantly in the presence of 100, 250, and 500 nM Ca2+, respectively. In addition, Ca2+ enhanced the membrane potential, the rate of oxygen consumption, and the NAD(P)H autofluorescence in these mitochondria. Direct measurement of α-GPDH activity showed that Ca2+ stimulated the enzyme by decreasing the Km for α-GR In those mitochondria where RET was eliminated by the Complex I inhibitor rotenone (2 μM) or due to depolarization by ADP (1 mM), the rate of H2O2 formation was smaller and the stimulation of H 2O2 generation by Ca2+ was prevented partly, but the stimulatory effect of Ca2+ was still significant. These data indicate that in α-GP-supported mitochondria activation of α-GPDH by Ca2+ leads to an accelerated RET-mediated ROS generation as well as to a stimulated ROS production by α-GPDH.
KW - α-glycerophosphate dehydrogenase
KW - Membrane potential
KW - NAD(P)H
KW - Reverse electron transport
KW - ROS
KW - Succinate
UR - http://www.scopus.com/inward/record.url?scp=35848959911&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=35848959911&partnerID=8YFLogxK
U2 - 10.1002/jnr.21405
DO - 10.1002/jnr.21405
M3 - Article
C2 - 17600838
AN - SCOPUS:35848959911
VL - 85
SP - 3471
EP - 3479
JO - Journal of Neuroscience Research
JF - Journal of Neuroscience Research
SN - 0360-4012
IS - 15
ER -