INT202218
From wiki-pain
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Sentences Mentioned In
Key: | Protein | Mutation | Event | Anatomy | Negation | Speculation | Pain term | Disease term |
Cells transduced with AdAcon showed a significant increase in m-aconitase mRNA (? | |||||||||||||||
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To confirm that m-aconitase levels were indeed increased, m-aconitase mRNA from AdAcon transduced cells was compared to cells transduced with AdGFP. | |||||||||||||||
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Astrogliosis may increase the amount of m-aconitase available for oxidative inactivation. | |||||||||||||||
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Transduction with AdAcon increases aconitase expression and activity in primary midbrain cultures | |||||||||||||||
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Both in vitro and in vivo studies have utilized oxidative inactivation of aconitase as an index of increased ROS levels. | |||||||||||||||
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Importantly, the time-course of cell death confirms that H2O2 formation and Fe2+ release occur hours prior to cell death, suggesting that oxidative inactivation of m-aconitase contributes to cell death in primary midbrain cultures.
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Oxidative inactivation of m-aconitase leads to cell death | |||||||||||||||
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Our data demonstrate that oxidative inactivation of m-aconitase results in the formation of Fenton reactants in neuronal cells which provides evidence for the pathogenic mechanism in which m-aconitase not only serves as a target but also as a source of oxidants. | |||||||||||||||
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Oxidative inactivation of overexpressed m-aconitase exacerbates H2O2 production and mitochondrial iron accumulation | |||||||||||||||
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Of note, the use of PQ2+ as a toxicant was particularly advantageous in our model because in contrast to neuron-specific toxicants such as MPP+, PQ2+ is capable of inactivating m-aconitase in both mixed neuronal/glial cultures and near pure astrocytic cultures [30]. | |||||||||||||||
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We therefore asked whether oxidative inactivation of m-aconitase resulted in mitochondrial dysfunction and cell death 18 hrs after PQ2+ incubation in AdGFP vs. | |||||||||||||||
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However, at a later time point of 18 hrs, when differences in cell viability were detected, m-aconitase overexpressing cells demonstrated a significant increase in PI+ cells in the presence of PQ2+ (Fig. 6b) suggesting that delayed cell death was resulting from m-aconitase inactivation. | |||||||||||||||
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However, whether oxidative inactivation of m-aconitase is a source of Fe2+ and H2O2 in intact neuronal cells and whether it contributes to neurotoxicity remains unknown. | |||||||||||||||
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We have previously shown that m-aconitase is oxidatively inactivated in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of parkinsonism and that this correlates with an increase in chelatable mitochondrial iron in the ventral midbrain region [16]. | |||||||||||||||
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Exacerbation of PQ2+-induced H2O2 production observed in m-aconitase overexpressing cultures presumably originates from the latter source due to increased m-aconitase available for inactivation by O2.? | |||||||||||||||
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The virus was tested for its ability to overexpress m-aconitase by Western blot analysis (data not shown), then grown in large scale and purified by CsCl gradient centrifugation.
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We hypothesized that increasing the levels of m-aconitase would increase the amount of target enzyme available for oxidative inactivation leading to exacerbation of H2O2 production, Fe2+ formation and cell death. | |||||||||||||||
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These transgenics exhibit lower basal levels of liver mitochondrial SOD2 mRNA and protein, lower SOD2 activity levels, reduced lipid oxidation, and increased aconitase activity in mitochondria compared with wild-type mice. | |||||||||||||||
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These MCAT mice generate 25% less heart mitochondrial H2O2 and H2O2-induced aconitase inactivation, suggesting increased protection from ROS. | |||||||||||||||
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Therefore we compared cytoplasmic dye accumulation to the total amount of MS channel activity evoked in the presence of FM1-43 or FM3-25. | |||||||||||||||
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