The Experts below are selected from a list of 285 Experts worldwide ranked by ideXlab platform
Matthew J. Picklo - One of the best experts on this subject based on the ideXlab platform.
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Oxidation of 4‐hydroxy‐2‐nonenal by succinic semialdehyde dehydrogenase (ALDH5A)
Journal of neurochemistry, 2004Co-Authors: Tonya C. Murphy, K. Michael Gibson, Venkataraman Amarnath, Matthew J. PickloAbstract:Elevated levels of 4-hydroxy-trans-2-nonenal (HNE) are implicated in the pathogenesis of numerous neurodegenerative disorders. Although well-characterized in the periphery, the mechanisms of detoxification of HNE in the CNS are unclear. HNE is oxidized to a non-toxic metabolite in the rat cerebral cortex by mitochondrial aldehyde dehydrogenases (ALDHs). Two possible ALDH enzymes which might oxidize HNE in CNS mitochondria are ALDH2 and succinic semialdehyde dehydrogenase (SSADH/ALDH5A). It was previously established that hepatic ALDH2 can oxidize HNE. In this work, we tested the hypothesis that SSADH oxidizes HNE. SSADH is critical in the detoxification of the GABA metabolite, succinic semialdehyde (SSA). Recombinant rat SSADH oxidized HNE and other α,β-unsaturated aldehydes. Inhibition and competition studies in rat brain mitochondria showed that SSADH was the predominant oxidizing enzyme for HNE but only contributed a portion of the total oxidizing activity in liver mitochondria. In vivo administration of diethyldithiocarbamate (DEDC) effectively inhibited (86%) ALDH2 activity but not HNE oxidation in liver mitochondria. The data suggest that a relationship between the detoxification of SSA and the neurotoxic aldehyde HNE exists in the CNS. Furthermore, these studies show that multiple hepatic aldehyde dehydrogenases are able to oxidize HNE.
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oxidation of 4 hydroxy 2 nonenal by succinic semialdehyde dehydrogenase aldh5a
Journal of Neurochemistry, 2004Co-Authors: Tonya C. Murphy, Michael K Gibson, Venkataraman Amarnath, Matthew J. PickloAbstract:Elevated levels of 4-hydroxy-trans-2-nonenal (HNE) are implicated in the pathogenesis of numerous neurodegenerative disorders. Although well-characterized in the periphery, the mechanisms of detoxification of HNE in the CNS are unclear. HNE is oxidized to a non-toxic metabolite in the rat cerebral cortex by mitochondrial aldehyde dehydrogenases (ALDHs). Two possible ALDH enzymes which might oxidize HNE in CNS mitochondria are ALDH2 and succinic semialdehyde dehydrogenase (SSADH/ALDH5A). It was previously established that hepatic ALDH2 can oxidize HNE. In this work, we tested the hypothesis that SSADH oxidizes HNE. SSADH is critical in the detoxification of the GABA metabolite, succinic semialdehyde (SSA). Recombinant rat SSADH oxidized HNE and other α,β-unsaturated aldehydes. Inhibition and competition studies in rat brain mitochondria showed that SSADH was the predominant oxidizing enzyme for HNE but only contributed a portion of the total oxidizing activity in liver mitochondria. In vivo administration of diethyldithiocarbamate (DEDC) effectively inhibited (86%) ALDH2 activity but not HNE oxidation in liver mitochondria. The data suggest that a relationship between the detoxification of SSA and the neurotoxic aldehyde HNE exists in the CNS. Furthermore, these studies show that multiple hepatic aldehyde dehydrogenases are able to oxidize HNE.
Tonya C. Murphy - One of the best experts on this subject based on the ideXlab platform.
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Oxidation of 4‐hydroxy‐2‐nonenal by succinic semialdehyde dehydrogenase (ALDH5A)
Journal of neurochemistry, 2004Co-Authors: Tonya C. Murphy, K. Michael Gibson, Venkataraman Amarnath, Matthew J. PickloAbstract:Elevated levels of 4-hydroxy-trans-2-nonenal (HNE) are implicated in the pathogenesis of numerous neurodegenerative disorders. Although well-characterized in the periphery, the mechanisms of detoxification of HNE in the CNS are unclear. HNE is oxidized to a non-toxic metabolite in the rat cerebral cortex by mitochondrial aldehyde dehydrogenases (ALDHs). Two possible ALDH enzymes which might oxidize HNE in CNS mitochondria are ALDH2 and succinic semialdehyde dehydrogenase (SSADH/ALDH5A). It was previously established that hepatic ALDH2 can oxidize HNE. In this work, we tested the hypothesis that SSADH oxidizes HNE. SSADH is critical in the detoxification of the GABA metabolite, succinic semialdehyde (SSA). Recombinant rat SSADH oxidized HNE and other α,β-unsaturated aldehydes. Inhibition and competition studies in rat brain mitochondria showed that SSADH was the predominant oxidizing enzyme for HNE but only contributed a portion of the total oxidizing activity in liver mitochondria. In vivo administration of diethyldithiocarbamate (DEDC) effectively inhibited (86%) ALDH2 activity but not HNE oxidation in liver mitochondria. The data suggest that a relationship between the detoxification of SSA and the neurotoxic aldehyde HNE exists in the CNS. Furthermore, these studies show that multiple hepatic aldehyde dehydrogenases are able to oxidize HNE.
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oxidation of 4 hydroxy 2 nonenal by succinic semialdehyde dehydrogenase aldh5a
Journal of Neurochemistry, 2004Co-Authors: Tonya C. Murphy, Michael K Gibson, Venkataraman Amarnath, Matthew J. PickloAbstract:Elevated levels of 4-hydroxy-trans-2-nonenal (HNE) are implicated in the pathogenesis of numerous neurodegenerative disorders. Although well-characterized in the periphery, the mechanisms of detoxification of HNE in the CNS are unclear. HNE is oxidized to a non-toxic metabolite in the rat cerebral cortex by mitochondrial aldehyde dehydrogenases (ALDHs). Two possible ALDH enzymes which might oxidize HNE in CNS mitochondria are ALDH2 and succinic semialdehyde dehydrogenase (SSADH/ALDH5A). It was previously established that hepatic ALDH2 can oxidize HNE. In this work, we tested the hypothesis that SSADH oxidizes HNE. SSADH is critical in the detoxification of the GABA metabolite, succinic semialdehyde (SSA). Recombinant rat SSADH oxidized HNE and other α,β-unsaturated aldehydes. Inhibition and competition studies in rat brain mitochondria showed that SSADH was the predominant oxidizing enzyme for HNE but only contributed a portion of the total oxidizing activity in liver mitochondria. In vivo administration of diethyldithiocarbamate (DEDC) effectively inhibited (86%) ALDH2 activity but not HNE oxidation in liver mitochondria. The data suggest that a relationship between the detoxification of SSA and the neurotoxic aldehyde HNE exists in the CNS. Furthermore, these studies show that multiple hepatic aldehyde dehydrogenases are able to oxidize HNE.
Hann S Huang - One of the best experts on this subject based on the ideXlab platform.
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phoenix nasa low temperature multi pollutant nox sox mercury control system for fossil fuel combustion
2007Co-Authors: Landy Chung, Hann S HuangAbstract:Phoenix Systems International, Inc. (PSII) and National Aeronautics and Space Administration (NASA) worked together to completed the development of the Low Temperature Multi-Pollutant Control System (MPCS). PSII and NASA jointly developed a gas-phase Oxidizer system that effectively (−100%) converts nitric oxide (NO), the primary NO x component from fossil-fuel combustion, to NO2. It was found that the NO Oxidizer system also oxidizes elemental Mercury in the gas phase, which ultimately led to a system that captures >95 percent of the total Mercury emissions. Capture of SO x (primarily SO2) was necessary in order to efficiently oxidize NO to NO2. The capture efficiency for SO x is >99 percent and the capture efficiency for NO x is >98 percent. All of these tests were performed on a 3 MWe slip-stream from a coal-fired power plant located in South Carolina by an EPA Certified independent laboratory.
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Phoenix-NASA Low Temperature Multi-Pollutant (NOx, SOx & Mercury) Control System for Fossil Fuel Combustion
Challenges of Power Engineering and Environment, 2007Co-Authors: Landy Chung, Hann S HuangAbstract:Phoenix Systems International, Inc. (PSII) and National Aeronautics and Space Administration (NASA) worked together to completed the development of the Low Temperature Multi-Pollutant Control System (MPCS). PSII and NASA jointly developed a gas-phase Oxidizer system that effectively (−100%) converts nitric oxide (NO), the primary NO x component from fossil-fuel combustion, to NO2. It was found that the NO Oxidizer system also oxidizes elemental Mercury in the gas phase, which ultimately led to a system that captures >95 percent of the total Mercury emissions. Capture of SO x (primarily SO2) was necessary in order to efficiently oxidize NO to NO2. The capture efficiency for SO x is >99 percent and the capture efficiency for NO x is >98 percent. All of these tests were performed on a 3 MWe slip-stream from a coal-fired power plant located in South Carolina by an EPA Certified independent laboratory.
Venkataraman Amarnath - One of the best experts on this subject based on the ideXlab platform.
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Oxidation of 4‐hydroxy‐2‐nonenal by succinic semialdehyde dehydrogenase (ALDH5A)
Journal of neurochemistry, 2004Co-Authors: Tonya C. Murphy, K. Michael Gibson, Venkataraman Amarnath, Matthew J. PickloAbstract:Elevated levels of 4-hydroxy-trans-2-nonenal (HNE) are implicated in the pathogenesis of numerous neurodegenerative disorders. Although well-characterized in the periphery, the mechanisms of detoxification of HNE in the CNS are unclear. HNE is oxidized to a non-toxic metabolite in the rat cerebral cortex by mitochondrial aldehyde dehydrogenases (ALDHs). Two possible ALDH enzymes which might oxidize HNE in CNS mitochondria are ALDH2 and succinic semialdehyde dehydrogenase (SSADH/ALDH5A). It was previously established that hepatic ALDH2 can oxidize HNE. In this work, we tested the hypothesis that SSADH oxidizes HNE. SSADH is critical in the detoxification of the GABA metabolite, succinic semialdehyde (SSA). Recombinant rat SSADH oxidized HNE and other α,β-unsaturated aldehydes. Inhibition and competition studies in rat brain mitochondria showed that SSADH was the predominant oxidizing enzyme for HNE but only contributed a portion of the total oxidizing activity in liver mitochondria. In vivo administration of diethyldithiocarbamate (DEDC) effectively inhibited (86%) ALDH2 activity but not HNE oxidation in liver mitochondria. The data suggest that a relationship between the detoxification of SSA and the neurotoxic aldehyde HNE exists in the CNS. Furthermore, these studies show that multiple hepatic aldehyde dehydrogenases are able to oxidize HNE.
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oxidation of 4 hydroxy 2 nonenal by succinic semialdehyde dehydrogenase aldh5a
Journal of Neurochemistry, 2004Co-Authors: Tonya C. Murphy, Michael K Gibson, Venkataraman Amarnath, Matthew J. PickloAbstract:Elevated levels of 4-hydroxy-trans-2-nonenal (HNE) are implicated in the pathogenesis of numerous neurodegenerative disorders. Although well-characterized in the periphery, the mechanisms of detoxification of HNE in the CNS are unclear. HNE is oxidized to a non-toxic metabolite in the rat cerebral cortex by mitochondrial aldehyde dehydrogenases (ALDHs). Two possible ALDH enzymes which might oxidize HNE in CNS mitochondria are ALDH2 and succinic semialdehyde dehydrogenase (SSADH/ALDH5A). It was previously established that hepatic ALDH2 can oxidize HNE. In this work, we tested the hypothesis that SSADH oxidizes HNE. SSADH is critical in the detoxification of the GABA metabolite, succinic semialdehyde (SSA). Recombinant rat SSADH oxidized HNE and other α,β-unsaturated aldehydes. Inhibition and competition studies in rat brain mitochondria showed that SSADH was the predominant oxidizing enzyme for HNE but only contributed a portion of the total oxidizing activity in liver mitochondria. In vivo administration of diethyldithiocarbamate (DEDC) effectively inhibited (86%) ALDH2 activity but not HNE oxidation in liver mitochondria. The data suggest that a relationship between the detoxification of SSA and the neurotoxic aldehyde HNE exists in the CNS. Furthermore, these studies show that multiple hepatic aldehyde dehydrogenases are able to oxidize HNE.
Umeo Takahama - One of the best experts on this subject based on the ideXlab platform.
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Oxidation of hydroxycinnamic acid and hydroxycinnamyl alcohol derivatives by laccase and peroxidase. Interactions among p‐hydroxyphenyl, guaiacyl and syringyl groups during the oxidation reactions
Physiologia Plantarum, 1995Co-Authors: Umeo TakahamaAbstract:Fungal laccase oxidized derivatives of hydroxycinnamic acid. The rates decreased in the order sinapic acid > ferulic acid ≥p-coumaric acid. The laccase oxidized sinapyl alcohol faster than coniferyl alcohol. The rates of oxidation of the hydroxycinnamic acid derivatives by an isoenzyme of peroxidase from horseradish decreased in the order p-coumaric acid > ferulic acid ≥ sinapic acid. The peroxidase oxidized coniferyl alcohol much faster than sinapyl alcohol. The laccase and the peroxidase predominantly oxidized (a) ferulic acid in a reaction mixture that contained p-coumaric acid and ferulic acid, (b) sinapic acid in a mixture of p-coumaric acid plus sinapic acid, and (c) sinapic acid in a mixture of ferulic acid plus sinapic acid. In a reaction mixture that contained both coniferyl and sinapyl alcohols, both fungal laccase and horseradish peroxidase predominantly oxidized sinapyl alcohol. From these results, it is concluded (1) that the p-hydroxyphenyl radical can oxidize guaiacyl and syringyl groups and produce their radicals and (2) that the guaiacyl radical can oxidize the syringyl group under formation of its radical; and that (3) in both cases the reverse reactions are very slow.
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oxidation of hydroxycinnamic acid and hydroxycinnamyl alcohol derivatives by laccase and peroxidase interactions among p hydroxyphenyl guaiacyl and syringyl groups during the oxidation reactions
Physiologia Plantarum, 1995Co-Authors: Umeo TakahamaAbstract:Fungal laccase oxidized derivatives of hydroxycinnamic acid. The rates decreased in the order sinapic acid > ferulic acid ≥p-coumaric acid. The laccase oxidized sinapyl alcohol faster than coniferyl alcohol. The rates of oxidation of the hydroxycinnamic acid derivatives by an isoenzyme of peroxidase from horseradish decreased in the order p-coumaric acid > ferulic acid ≥ sinapic acid. The peroxidase oxidized coniferyl alcohol much faster than sinapyl alcohol. The laccase and the peroxidase predominantly oxidized (a) ferulic acid in a reaction mixture that contained p-coumaric acid and ferulic acid, (b) sinapic acid in a mixture of p-coumaric acid plus sinapic acid, and (c) sinapic acid in a mixture of ferulic acid plus sinapic acid. In a reaction mixture that contained both coniferyl and sinapyl alcohols, both fungal laccase and horseradish peroxidase predominantly oxidized sinapyl alcohol. From these results, it is concluded (1) that the p-hydroxyphenyl radical can oxidize guaiacyl and syringyl groups and produce their radicals and (2) that the guaiacyl radical can oxidize the syringyl group under formation of its radical; and that (3) in both cases the reverse reactions are very slow.
