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Villa RF, Ferrari F, Gorini A. Effects of Chronic Hypertension on the Energy Metabolism of Cerebral Cortex Mitochondria in Normotensive and in Spontaneously Hypertensive Rats During Aging. Neuromolecular Med 2024; 26:2. [PMID: 38393429 DOI: 10.1007/s12017-023-08772-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Accepted: 12/02/2023] [Indexed: 02/25/2024]
Abstract
In this study the subcellular modifications undergone by cerebral cortex mitochondrial metabolism in chronic hypertension during aging were evaluated. The catalytic properties of regulatory energy-linked enzymes of Tricarboxylic Acid Cycle (TCA), Electron Transport Chain (ETC) and glutamate metabolism were assayed on non-synaptic mitochondria (FM, located in post-synaptic compartment) and on intra-synaptic mitochondria of pre-synaptic compartment, furtherly divided in "light" (LM) and "heavy" (HM) mitochondria, purified form cerebral cortex of normotensive Wistar Kyoto Rats (WKY) versus Spontaneously Hypertensive Rats (SHR) at 6, 12 and 18 months. During physiological aging, the metabolic machinery was differently expressed in pre- and post-synaptic compartments: LM and above all HM were more affected by aging, displaying lower ETC activities. In SHR at 6 months, FM and LM showed an uncoupling between TCA and ETC, likely as initial adaptive response to hypertension. During pathological aging, HM were particularly affected at 12 months in SHR, as if the adaptive modifications in FM and LM at 6 months granted a mitochondrial functional balance, while at 18 months all the neuronal mitochondria displayed decreased metabolic fluxes versus WKY. This study describes the effects of chronic hypertension on cerebral mitochondrial energy metabolism during aging through functional proteomics of enzymes at subcellular levels, i.e. in neuronal soma and synapses. In addition, this represents the starting point to envisage an experimental physiopathological model which could be useful also for pharmacological studies, to assess drug actions during the development of age-related pathologies that could coexist and/or are provoked by chronic hypertension.
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Affiliation(s)
- Roberto Federico Villa
- Department of Biology and Biotechnology, Laboratory of Pharmacology and Molecular Medicine of Central Nervous System, University of Pavia, Via Ferrata, 9, 27100, Pavia, Italy.
| | - Federica Ferrari
- Department of Biology and Biotechnology, Laboratory of Pharmacology and Molecular Medicine of Central Nervous System, University of Pavia, Via Ferrata, 9, 27100, Pavia, Italy
- School of Neurology, Department of Brain and Behavioral Sciences, University of Pavia, Via Bassi. 21, 27100, Pavia, Italy
| | - Antonella Gorini
- Department of Biology and Biotechnology, Laboratory of Pharmacology and Molecular Medicine of Central Nervous System, University of Pavia, Via Ferrata, 9, 27100, Pavia, Italy
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Wang H, Chen J, Guo R, Wang D, Wang T, Sun Y. Exogenous brassinolide treatment regulates phenolic accumulation in mung bean sprouts through the modulation of sugar and energy metabolism. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2024; 104:1656-1667. [PMID: 37851693 DOI: 10.1002/jsfa.13060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 10/10/2023] [Accepted: 10/19/2023] [Indexed: 10/20/2023]
Abstract
BACKGROUND The effects of exogenous brassinolide (BR) treatment (3.0 μmol L-1 ) on phenolic biosynthesis in mung bean sprouts were investigated. This investigation included the analysis of sugar content, substrates within the phenylpropane pathway, energy substances, enzymatic activity within the phenylpropane pathway, sugar metabolism and energy metabolism. RESULTS Results showed that BR treatment significantly increased the levels of total phenolics, p-hydroxybenzoic acid, p-coumaric acid, gallic acid, fumalic acid and caffeic acid. This enhancement was accomplished through the elevation of l-phenylalanine levels and the activation of enzymes associated with the phenylpropane pathway in mung bean sprouts, including phenylalanine ammonia-lyase, cinnamate 4-hydroxylase and 4-coumarate CoA ligase. Furthermore, BR treatment induced alterations in sugar metabolism in mung bean sprouts as evidenced by the increased levels of glucose, fructose, sucrose and phosphoenolpyruvate. Moreover, increased activity was observed for enzymes linked to sucrose metabolism and glycolysis in the BR-treated group. Concurrently, BR treatment bolstered the levels of adenosine triphosphate and energy charge in mung bean sprouts, which was attributed to the activation of H+ -adenosine triphosphatase, Ca2+ -adenosine triphosphatase and succinic dehydrogenase. CONCLUSION These results suggest that BR treatment can accelerate the accumulation of phenolic compounds in mung bean sprouts. This effect is achieved not only through the activation of the phenylpropane pathway, but also through the modulation of sugar and energy metabolism. The modulation provides ample energy and a substrate for the biosynthesis of phenolics. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Hanbo Wang
- College of Life Science, Henan Normal University, Xinxiang, China
| | - Jinghao Chen
- College of Life Science, Henan Normal University, Xinxiang, China
| | - Runjiu Guo
- College of Life Science, Henan Normal University, Xinxiang, China
| | - Dan Wang
- College of Life Science, Henan Normal University, Xinxiang, China
| | - Taixia Wang
- College of Life Science, Henan Normal University, Xinxiang, China
| | - Yali Sun
- College of Life Science, Henan Normal University, Xinxiang, China
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Li Y, Zuo X, Ji N, Zhang J, Wang K, Jin P, Zheng Y. PpMYB1 and PpNPR1 interact to enhance the resistance of peach fruit to Rhizopus stolonifer infection. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 198:107682. [PMID: 37060868 DOI: 10.1016/j.plaphy.2023.107682] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 03/18/2023] [Accepted: 04/03/2023] [Indexed: 05/07/2023]
Abstract
MYB transcription factors play important role in stress-resistance of plants. Nevertheless, the function of MYB TFs in peach Rhizopus rot remains poorly understood. Herein, Pichia guilliermondii treatment activated resistance against Rhizopus stolonifer, as illustrated by reductions in the incidence rate and severity of Rhizopus rot disease, increased enzyme activities and gene expression of chitinase (CHI) and β-1,3-glucanase (GLU), and enhancement of energy production by inducing the activities and expression of H+-ATPase and Ca2+-ATPase, succinate dehydrogenase (SDH), and cytochrome c oxidase (CCO). Moreover, an R1-type MYB, PpMYB1, from peach fruit was induced during R. stolonifer infection and in response to P. guilliermondii treatment. PpMYB1 activated the transcription of PpCHI-EP3 and PpGLU-like genes and the energy metabolism-related gene PpH+-ATPase1 by directly targeting the MBS element. Importantly, PpMYB1 interacted with PpNPR1 to form a heterodimer, which was conducive to enhancing the activation of target gene transcription. Collectively, our findings suggest that PpMYB1 cooperates with PpNPR1 to positively regulate disease resistance by activating the disease defense system and energy metabolism in peaches.
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Affiliation(s)
- Yanfei Li
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Xiaoxia Zuo
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Nana Ji
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Jinglin Zhang
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Kaituo Wang
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Peng Jin
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Yonghua Zheng
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, PR China.
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Lin D, Yan R, Xing M, Liao S, Chen J, Gan Z. Fucoidan treatment alleviates chilling injury in cucumber by regulating ROS homeostasis and energy metabolism. FRONTIERS IN PLANT SCIENCE 2022; 13:1107687. [PMID: 36618644 PMCID: PMC9816408 DOI: 10.3389/fpls.2022.1107687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
INTRODUCTION Chilling injury is a major hindrance to cucumber fruit quality during cold storage. METHODS AND RESULTS In this study, we evaluated the effects of fucoidan on fruit quality, reactive oxygen species homeostasis, and energy metabolism in cucumbers during cold storage. The results showed that, compared with the control cucumber fruit, fucoidan-treated cucumber fruit exhibited a lower chilling injury index and less weight loss, as well as reduced electrolyte leakage and malondialdehyde content. The most pronounced effects were observed following treatment with fucoidan at 15 g/L, which resulted in increased 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radical scavenging rates and reduced superoxide anion production rate and hydrogen peroxide content. The expression and activity levels of peroxidase, catalase, and superoxide dismutase were enhanced by fucoidan treatment. Further, fucoidan treatment maintained high levels of ascorbic acid and glutathione, and high ratios of ascorbic acid/dehydroascorbate and glutathione/oxidized glutathione. Moreover, fucoidan treatment increased the activities of ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, and glutathione reductase and their gene expression. Fucoidan treatment significantly delayed the decrease in ATP and ADP, while preventing an increase in AMP content. Finally, fucoidan treatment delayed the decrease of energy charge and the activities and gene expression of H+-ATPase, Ca2+-ATPase, cytochrome c oxidase, and succinate dehydrogenase in cucumber fruits. CONCLUSION Altogether, our findings indicate that fucoidan can effectively enhance antioxidant capacity and maintain energy metabolism, thereby improving cucumber cold resistance during cold storage.
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Eprintsev AT, Fedorin DN, Bakarev MY. [Molecular and biochemical studies of succinate dehydrogenase in rat liver under conditions of alloxan diabetes]. BIOMEDITSINSKAIA KHIMIIA 2022; 68:272-278. [PMID: 36005845 DOI: 10.18097/pbmc20226804272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Experimental alloxan diabetes in rats causes an increase in the activity of liver succinate dehydrogenase (SDH) without changes in its isozyme composition. The observed increase in the catalytic activity of SDH clearly correlates with the intensification of transcription of the genes encoding catalytic dimer of SDH. Analysis of the methyl status of the promoters of the genes, encoding the catalytic dimer of SDH in rats under normal and experimental conditions did not reveal any dependence on the level of their expression. The obtained results of bisulfite sequencing indicate a passive role of the epigenetic mechanism of regulation of SDH gene expression in the development of alloxan diabetes. The transcription factor CREB, responsible for of gluconeogenesis in diabetes, may play an important role in the control of the transcriptional activity of the sdha and sdhb genes.
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Mouli MSSV, Mishra AK. Synthesis, characterization and photophysical studies of the flavopeptide conjugates as model for the covalently linked flavoenzymes. J CHEM SCI 2022. [DOI: 10.1007/s12039-022-02050-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Kan J, Liu Y, Hui Y, Wan B, Liu J, Qian C, Jin C. 2‐aminoindan‐2‐phosphonic acid alleviates oxidative browning in fresh‐cut lily bulbs. J FOOD PROCESS PRES 2022. [DOI: 10.1111/jfpp.16449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Juan Kan
- College of Food Science and Engineering Yangzhou University Yangzhou China
| | - Ying Liu
- College of Food Science and Engineering Yangzhou University Yangzhou China
| | - Yaoyao Hui
- College of Food Science and Engineering Yangzhou University Yangzhou China
| | - Bing Wan
- College of Food Science and Engineering Yangzhou University Yangzhou China
| | - Jun Liu
- College of Food Science and Engineering Yangzhou University Yangzhou China
| | - Chunlu Qian
- College of Food Science and Engineering Yangzhou University Yangzhou China
| | - Changhai Jin
- College of Food Science and Engineering Yangzhou University Yangzhou China
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Wang Y, Zhang X, Yao H, Chen X, Shang L, Li P, Cui X, Zeng J. Peroxisome-generated succinate induces lipid accumulation and oxidative stress in the kidneys of diabetic mice. J Biol Chem 2022; 298:101660. [PMID: 35124006 PMCID: PMC8881667 DOI: 10.1016/j.jbc.2022.101660] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 01/13/2023] Open
Abstract
Diabetes normally causes lipid accumulation and oxidative stress in the kidneys, which plays a critical role in the onset of diabetic nephropathy; however, the mechanism by which dysregulated fatty acid metabolism increases lipid and reactive oxygen species (ROS) formation in the diabetic kidney is not clear. As succinate is remarkably increased in the diabetic kidney, and accumulation of succinate suppresses mitochondrial fatty acid oxidation and increases ROS formation, we hypothesized that succinate might play a role in inducing lipid and ROS accumulation in the diabetic kidney. Here we demonstrate a novel mechanism by which diabetes induces lipid and ROS accumulation in the kidney of diabetic animals. We show that enhanced oxidation of dicarboxylic acids by peroxisomes leads to lipid and ROS accumulation in the kidney of diabetic mice via the metabolite succinate. Furthermore, specific suppression of peroxisomal β-oxidation improved diabetes-induced nephropathy by reducing succinate generation and attenuating lipid and ROS accumulation in the kidneys of the diabetic mice. We suggest that peroxisome-generated succinate acts as a pathological molecule inducing lipid and ROS accumulation in kidney, and that specifically targeting peroxisomal β-oxidation might be an effective strategy in treating diabetic nephropathy and related metabolic disorders.
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Nitric Oxide Extends the Postharvest Life of Water Bamboo Shoots Partly by Maintaining Mitochondrial Structure and Energy Metabolism. Int J Mol Sci 2022; 23:ijms23031607. [PMID: 35163530 PMCID: PMC8835775 DOI: 10.3390/ijms23031607] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/25/2022] [Accepted: 01/27/2022] [Indexed: 11/23/2022] Open
Abstract
Harvested water bamboo shoots can be stored for only a few days before they lose weight and become soft. Nitrogen oxide (NO) and modified atmosphere packaging (MAP) have previously been used to prolong horticultural crop storage. In the present study, we analyzed the joint effect of these two methods on extending the postharvest quality of water bamboo shoots. Water bamboo shoots were treated with (1) 30 μL L−1 NO, (2) MAP, and (3) a combination of NO and MAP. The NO treatment delayed the softness and weight loss through maintaining the integrity of the mitochondrial ultrastructure and enhancing the ATP level by activating the expressions and activities of succinic dehydrogenase, malic acid dehydrogenase, and cytochrome oxidase. MAP improved the effect of NO on the mitochondrial energy metabolism. These results indicate that NO and MAP treatments are effective at suppressing the quality deterioration of water bamboo shoots, MAP improves the effect of NO in extending postharvest life, and NO may be the main effective factor in the combination of NO and MAP.
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Ji N, Li Y, Wang J, Zuo X, Li M, Jin P, Zheng Y. Interaction of PpWRKY46 and PpWRKY53 regulates energy metabolism in MeJA primed disease resistance of peach fruit. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2022; 171:157-168. [PMID: 34999507 DOI: 10.1016/j.plaphy.2021.12.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 12/25/2021] [Accepted: 12/29/2021] [Indexed: 05/27/2023]
Abstract
Induced resistance is a promising strategy to manage plant disease, while adequate energy supply is crucial to plant defense. Our previous study has revealed that PpWRKY45 and PpWRKY70 are involved in MeJA-primed disease resistance by regulating jasmonate acid biosynthesis and phenylpropanoid metabolism. Herein, the possible role of WRKYs in MeJA-primed disease resistance and energy metabolism was investigated. PpWRKY46 and PpWRKY53 were up- and down-regulated, respectively, by MeJA treatment. The activities and gene expression of energy metabolism-related enzymes and energy status were promoted by MeJA treatment and R. stolonifer inoculation during 60 h storage at 20 °C. Energy metabolism-related genes, including PpSDH and PpCOX15 were transactivated by PpWRKY46, but repressed by PpWRKY53. Furthermore, PpWRKY46 interacted with PpWRKY53 to attenuate the transcriptional repression of PpWRKY53 to PpSDH and PpCOX15. Taken together, our results demonstrated that the counteraction of PpWRKY46 and PpWRKY53 contributes to MeJA-primed defense by regulating energy metabolism in peaches.
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Affiliation(s)
- Nana Ji
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Yanfei Li
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Jing Wang
- College of Food Science and Technology, Jiangxi Agricultural University, Nanchang, 330045, PR China
| | - Xiaoxia Zuo
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Meilin Li
- College of Food Science, Shenyang Agricultural University, Shenyang, 110866, PR China
| | - Peng Jin
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Yonghua Zheng
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, PR China.
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Mitochondrial iron-sulfur clusters: Structure, function, and an emerging role in vascular biology. Redox Biol 2021; 47:102164. [PMID: 34656823 PMCID: PMC8577454 DOI: 10.1016/j.redox.2021.102164] [Citation(s) in RCA: 98] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 10/04/2021] [Accepted: 10/08/2021] [Indexed: 12/31/2022] Open
Abstract
Iron-sulfur (Fe-S) clusters are essential cofactors most commonly known for their role mediating electron transfer within the mitochondrial respiratory chain. The Fe-S cluster pathways that function within the respiratory complexes are highly conserved between bacteria and the mitochondria of eukaryotic cells. Within the electron transport chain, Fe-S clusters play a critical role in transporting electrons through Complexes I, II and III to cytochrome c, before subsequent transfer to molecular oxygen. Fe-S clusters are also among the binding sites of classical mitochondrial inhibitors, such as rotenone, and play an important role in the production of mitochondrial reactive oxygen species (ROS). Mitochondrial Fe-S clusters also play a critical role in the pathogenesis of disease. High levels of ROS produced at these sites can cause cell injury or death, however, when produced at low levels can serve as signaling molecules. For example, Ndufs2, a Complex I subunit containing an Fe-S center, N2, has recently been identified as a redox-sensitive oxygen sensor, mediating homeostatic oxygen-sensing in the pulmonary vasculature and carotid body. Fe-S clusters are emerging as transcriptionally-regulated mediators in disease and play a crucial role in normal physiology, offering potential new therapeutic targets for diseases including malaria, diabetes, and cancer.
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Gonchar OO, Maznychenko AV, Klyuchko OM, Mankovska IM, Butowska K, Borowik A, Piosik J, Sokolowska I. C 60 Fullerene Reduces 3-Nitropropionic Acid-Induced Oxidative Stress Disorders and Mitochondrial Dysfunction in Rats by Modulation of p53, Bcl-2 and Nrf2 Targeted Proteins. Int J Mol Sci 2021; 22:ijms22115444. [PMID: 34064070 PMCID: PMC8196695 DOI: 10.3390/ijms22115444] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 05/16/2021] [Accepted: 05/19/2021] [Indexed: 01/23/2023] Open
Abstract
C60 fullerene as a potent free radical scavenger and antioxidant could be a beneficial means for neurodegenerative disease prevention or cure. The aim of the study was to define the effects of C60 administration on mitochondrial dysfunction and oxidative stress disorders in a 3-nitropropionic acid (3-NPA)-induced rat model of Huntington’s disease. Animals received 3-NPA (30 mg/kg i.p.) once a day for 3 consecutive days. C60 was applied at a dose of 0.5 mg/kg of body weight, i.p. daily over 5 days before (C60 pre-treatment) and after 3-NPA exposure (C60 post-treatment). Oxidative stress biomarkers, the activity of respiratory chain enzymes, the level of antioxidant defense, and pro- and antiapoptotic markers were analyzed in the brain and skeletal muscle mitochondria. The nuclear and cytosol Nrf2 protein expression, protein level of MnSOD, γ-glutamate-cysteine ligase (γ-GCLC), and glutathione-S-transferase (GSTP) as Nrf2 targets were evaluated. Our results indicated that C60 can prevent 3-NPA-induced mitochondrial dysfunction through the restoring of mitochondrial complexes’ enzyme activity, ROS scavenging, modulating of pro/antioxidant balance and GSH/GSSG ratio, as well as inhibition of mitochondria-dependent apoptosis through the limitation of p53 mitochondrial translocation and increase in Bcl-2 protein expression. C60 improved mitochondrial protection by strengthening the endogenous glutathione system via glutathione biosynthesis by up-regulating Nrf2 nuclear accumulation as well as GCLC and GSTP protein level.
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Affiliation(s)
- Olga O. Gonchar
- Department of Hypoxic States and Department of Movements Physiology, Bogomoletz Institute of Physiology, Bogomoletz Str. 4, 01024 Kyiv, Ukraine; (O.O.G.); (I.M.M.)
| | - Andriy V. Maznychenko
- Department of Hypoxic States and Department of Movements Physiology, Bogomoletz Institute of Physiology, Bogomoletz Str. 4, 01024 Kyiv, Ukraine; (O.O.G.); (I.M.M.)
- Department of Physical Education, Gdansk University of Physical Education and Sport, Kazimierza Gorskiego Str. 1, 80-336 Gdansk, Poland;
- Correspondence:
| | - Olena M. Klyuchko
- Department of Electronics, National Aviation University, L. Huzar Ave. 1, 03058 Kyiv, Ukraine;
| | - Iryna M. Mankovska
- Department of Hypoxic States and Department of Movements Physiology, Bogomoletz Institute of Physiology, Bogomoletz Str. 4, 01024 Kyiv, Ukraine; (O.O.G.); (I.M.M.)
| | - Kamila Butowska
- Laboratory of Biophysics, Intercollegiate Faculty of Biotechnology UG-MUG, Abrahama 58, 80-307 Gdansk, Poland; (K.B.); (A.B.); (J.P.)
| | - Agnieszka Borowik
- Laboratory of Biophysics, Intercollegiate Faculty of Biotechnology UG-MUG, Abrahama 58, 80-307 Gdansk, Poland; (K.B.); (A.B.); (J.P.)
| | - Jacek Piosik
- Laboratory of Biophysics, Intercollegiate Faculty of Biotechnology UG-MUG, Abrahama 58, 80-307 Gdansk, Poland; (K.B.); (A.B.); (J.P.)
| | - Inna Sokolowska
- Department of Physical Education, Gdansk University of Physical Education and Sport, Kazimierza Gorskiego Str. 1, 80-336 Gdansk, Poland;
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Seidlmayer LK, Hanson BJ, Thai PN, Schaefer S, Bers DM, Dedkova EN. PK11195 Protects From Cell Death Only When Applied During Reperfusion: Succinate-Mediated Mechanism of Action. Front Physiol 2021; 12:628508. [PMID: 34149440 PMCID: PMC8212865 DOI: 10.3389/fphys.2021.628508] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 04/28/2021] [Indexed: 11/13/2022] Open
Abstract
Aim: Reperfusion after myocardial ischemia causes cellular injury, in part due to changes in mitochondrial Ca2+ handling, oxidative stress, and myocyte energetics. We have previously shown that the 18-kDa translocator protein of the outer mitochondrial membrane (TSPO) can modulate Ca2+ handling. Here, we aim to evaluate the role of the TSPO in ischemia/reperfusion (I/R) injury. Methods: Rabbit ventricular myocytes underwent simulated acute ischemia (20 min) and reperfusion (at 15 min, 1 h, and 3 h) in the absence and presence of 50 μM PK11195, a TSPO inhibitor. Cell death was measured by lactate dehydrogenase (LDH) assay, while changes in mitochondrial Ca2+, membrane potential (ΔΨm), and reactive oxygen species (ROS) generation were monitored using confocal microscopy in combination with fluorescent indicators. Substrate utilization was measured with Biolog mitochondrial plates. Results: Cell death was increased by ~200% following I/R compared to control untreated ventricular myocytes. Incubation with 50 μM PK11195 during both ischemia and reperfusion did not reduce cell death but increased mitochondrial Ca2+ uptake and ROS generation. However, application of 50 μM PK11195 only at the onset and during reperfusion effectively protected against cell death. The large-scale oscillations in ΔΨm observed after ~1 h of reperfusion were significantly delayed by 1 μM cyclosporin A and almost completely prevented by 50 μM PK11195 applied during 3 h of reperfusion. After an initial increase, mitochondrial Ca2+, measured with Myticam, rapidly declined during 3 h of reperfusion after the initial transient increase. This decline was prevented by application of PK11195 at the onset and during reperfusion. PK11195 prevented a significant increase in succinate utilization following I/R and succinate-induced forward-mode ROS generation. Treatment with PK11195 was also associated with a significant increase in glutamate and a decrease in leucine utilization. Conclusion: PK11195 administered specifically at the moment of reperfusion limited ROS-induced ROS release and cell death, likely in part, by a shift from succinate to glutamate utilization. These data demonstrate a unique mechanism to limit cardiac injury after I/R.
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Affiliation(s)
- Lea K Seidlmayer
- Department of Cardiology, University Hospital Olbenburg, Olbenburg, Germany
| | - Benjamin J Hanson
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | - Phung N Thai
- Department of Internal Medicine, Division of Cardiovascular Medicine, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Saul Schaefer
- Department of Internal Medicine, Division of Cardiovascular Medicine, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Donald M Bers
- Department of Pharmacology, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Elena N Dedkova
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
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Brain Insulin Resistance: Focus on Insulin Receptor-Mitochondria Interactions. Life (Basel) 2021; 11:life11030262. [PMID: 33810179 PMCID: PMC8005009 DOI: 10.3390/life11030262] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/12/2021] [Accepted: 03/16/2021] [Indexed: 02/07/2023] Open
Abstract
Current hypotheses implicate insulin resistance of the brain as a pathogenic factor in the development of Alzheimer’s disease and other dementias, Parkinson’s disease, type 2 diabetes, obesity, major depression, and traumatic brain injury. A variety of genetic, developmental, and metabolic abnormalities that lead to disturbances in the insulin receptor signal transduction may underlie insulin resistance. Insulin receptor substrate proteins are generally considered to be the node in the insulin signaling system that is critically involved in the development of insulin insensitivity during metabolic stress, hyperinsulinemia, and inflammation. Emerging evidence suggests that lower activation of the insulin receptor (IR) is another common, while less discussed, mechanism of insulin resistance in the brain. This review aims to discuss causes behind the diminished activation of IR in neurons, with a focus on the functional relationship between mitochondria and IR during early insulin signaling and the related roles of oxidative stress, mitochondrial hypometabolism, and glutamate excitotoxicity in the development of IR insensitivity to insulin.
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Jain A, Nilatawong P, Mamak N, Jensen LT, Jensen AN. Disruption in iron homeostasis and impaired activity of iron-sulfur cluster containing proteins in the yeast model of Shwachman-Diamond syndrome. Cell Biosci 2020; 10:105. [PMID: 32944219 PMCID: PMC7488397 DOI: 10.1186/s13578-020-00468-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 09/04/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Shwachman-Diamond syndrome (SDS) is a congenital disease that affects the bone marrow, skeletal system, and pancreas. The majority of patients with SDS have mutations in the SBDS gene, involved in ribosome biogenesis as well as other processes. A Saccharomyces cerevisiae model of SDS, lacking Sdo1p the yeast orthologue of SBDS, was utilized to better understand the molecular pathogenesis in the development of this disease. RESULTS Deletion of SDO1 resulted in a three-fold over-accumulation of intracellular iron. Phenotypes associated with impaired iron-sulfur (ISC) assembly, up-regulation of the high affinity iron uptake pathway, and reduced activities of ISC containing enzymes aconitase and succinate dehydrogenase, were observed in sdo1∆ yeast. In cells lacking Sdo1p, elevated levels of reactive oxygen species (ROS) and protein oxidation were reduced with iron chelation, using a cell impermeable iron chelator. In addition, the low activity of manganese superoxide dismutase (Sod2p) seen in sdo1∆ cells was improved with iron chelation, consistent with the presence of reactive iron from the ISC assembly pathway. In yeast lacking Sdo1p, the mitochondrial voltage-dependent anion channel (VDAC) Por1p is over-expressed and its deletion limits iron accumulation and increases activity of aconitase and succinate dehydrogenase. CONCLUSIONS We propose that oxidative stress from POR1 over-expression, resulting in impaired activity of ISC containing proteins and disruptions in iron homeostasis, may play a role in disease pathogenesis in SDS patients.
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Affiliation(s)
- Ayushi Jain
- Department of Pathobiology, Faculty of Science, Mahidol University, 272 Rama 6 Road, Bangkok, 10400 Thailand
| | - Phubed Nilatawong
- Department of Pathobiology, Faculty of Science, Mahidol University, 272 Rama 6 Road, Bangkok, 10400 Thailand
- Division of Biopharmacy, Faculty of Pharmaceutical Sciences, Ubon Ratchathani University, Ubon Ratchathani, 34190 Thailand
| | - Narinrat Mamak
- Toxicology Graduate Program, Faculty of Science, Mahidol University, Bangkok, 10400 Thailand
| | - Laran T. Jensen
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, 10400 Thailand
| | - Amornrat Naranuntarat Jensen
- Department of Pathobiology, Faculty of Science, Mahidol University, 272 Rama 6 Road, Bangkok, 10400 Thailand
- Pathology Information and Learning Center, Department of Pathobiology, Faculty of Science, Mahidol University, Bangkok, 10400 Thailand
- Center of Excellence on Environmental Health and Toxicology (EHT), Bangkok, Thailand
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16
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Viviani VR, Silva JR, Amaral DT, Bevilaqua VR, Abdalla FC, Branchini BR, Johnson CH. A new brilliantly blue-emitting luciferin-luciferase system from Orfelia fultoni and Keroplatinae (Diptera). Sci Rep 2020; 10:9608. [PMID: 32541805 PMCID: PMC7295969 DOI: 10.1038/s41598-020-66286-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 05/07/2020] [Indexed: 12/18/2022] Open
Abstract
Larvae of O. fultoni (Keroplatidae: Keroplatinae), which occur along river banks in the Appalachian Mountains in Eastern United States, produce the bluest bioluminescence among insects from translucent areas associated to black bodies, which are located mainly in the anterior and posterior parts of the body. Although closely related to Arachnocampa spp (Keroplatidae: Arachnocampininae), O.fultoni has a morphologically and biochemically distinct bioluminescent system which evolved independently, requiring a luciferase enzyme, a luciferin, a substrate binding fraction (SBF) that releases luciferin in the presence of mild reducing agents, molecular oxygen, and no additional cofactors. Similarly, the closely related Neoceroplatus spp, shares the same kind of luciferin-luciferase system of Orfelia fultoni. However, the molecular properties, identities and functions of luciferases, SBF and luciferin of Orfelia fultoni and other luminescent members of the Keroplatinae subfamily still remain to be fully elucidated. Using O. fultoni as a source of luciferase, and the recently discovered non-luminescent cave worm Neoditomiya sp as the main source of luciferin and SBF, we isolated and initially characterized these compounds. The luciferase of O. fultoni is a stable enzyme active as an apparent trimer (220 kDa) composed of ~70 kDa monomers, with an optimum pH of 7.8. The SBF, which is found in the black bodies in Orfelia fultoni and in smaller dark granules in Neoditomiya sp, consists of a high molecular weight complex of luciferin and proteins, apparently associated to mitochondria. The luciferin, partially purified from hot extracts by a combination of anion exchange chromatography and TLC, is a very polar and weakly fluorescent compound, whereas its oxidized product displays blue fluorescence with an emission spectrum matching the bioluminescence spectrum (~460 nm), indicating that it is oxyluciferin. The widespread occurrence of luciferin and SBF in both luminescent and non-luminescent Keroplatinae larvae indicate an additional important biological function for the substrate, and therefore the name keroplatin.
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Affiliation(s)
- Vadim R Viviani
- Graduate School of Biotechnology and Environmental Monitoring (UFSCar), Federal University of São Carlos (UFSCar), Sorocaba, Brazil.
- Graduate School of Evolutive Genetics and Molecular Biology (UFSCar), São Carlos, Brazil.
| | - Jaqueline R Silva
- Graduate School of Biotechnology and Environmental Monitoring (UFSCar), Federal University of São Carlos (UFSCar), Sorocaba, Brazil
| | - Danilo T Amaral
- Graduate School of Biotechnology and Environmental Monitoring (UFSCar), Federal University of São Carlos (UFSCar), Sorocaba, Brazil
| | - Vanessa R Bevilaqua
- Graduate School of Evolutive Genetics and Molecular Biology (UFSCar), São Carlos, Brazil
| | - Fabio C Abdalla
- Graduate School of Biotechnology and Environmental Monitoring (UFSCar), Federal University of São Carlos (UFSCar), Sorocaba, Brazil
| | - Bruce R Branchini
- Department of Chemistry, Connecticut College, New London, Connecticut, USA
| | - Carl H Johnson
- Dept. Biological Sciences, Vanderbilt University, Nashville, TN, USA
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17
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Zhao RZ, Jiang S, Zhang L, Yu ZB. Mitochondrial electron transport chain, ROS generation and uncoupling (Review). Int J Mol Med 2019; 44:3-15. [PMID: 31115493 PMCID: PMC6559295 DOI: 10.3892/ijmm.2019.4188] [Citation(s) in RCA: 451] [Impact Index Per Article: 90.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Accepted: 04/19/2019] [Indexed: 12/18/2022] Open
Abstract
The mammalian mitochondrial electron transport chain (ETC) includes complexes I-IV, as well as the electron transporters ubiquinone and cytochrome c. There are two electron transport pathways in the ETC: Complex I/III/IV, with NADH as the substrate and complex II/III/IV, with succinic acid as the substrate. The electron flow is coupled with the generation of a proton gradient across the inner membrane and the energy accumulated in the proton gradient is used by complex V (ATP synthase) to produce ATP. The first part of this review briefly introduces the structure and function of complexes I-IV and ATP synthase, including the specific electron transfer process in each complex. Some electrons are directly transferred to O2 to generate reactive oxygen species (ROS) in the ETC. The second part of this review discusses the sites of ROS generation in each ETC complex, including sites IF and IQ in complex I, site IIF in complex II and site IIIQo in complex III, and the physiological and pathological regulation of ROS. As signaling molecules, ROS play an important role in cell proliferation, hypoxia adaptation and cell fate determination, but excessive ROS can cause irreversible cell damage and even cell death. The occurrence and development of a number of diseases are closely related to ROS overproduction. Finally, proton leak and uncoupling proteins (UCPS) are discussed. Proton leak consists of basal proton leak and induced proton leak. Induced proton leak is precisely regulated and induced by UCPs. A total of five UCPs (UCP1-5) have been identified in mammalian cells. UCP1 mainly plays a role in the maintenance of body temperature in a cold environment through non-shivering thermogenesis. The core role of UCP2-5 is to reduce oxidative stress under certain conditions, therefore exerting cytoprotective effects. All diseases involving oxidative stress are associated with UCPs.
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Affiliation(s)
- Ru-Zhou Zhao
- Department of Aerospace Physiology, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Shuai Jiang
- Department of Aerospace Physiology, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Lin Zhang
- Department of Aerospace Physiology, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Zhi-Bin Yu
- Department of Aerospace Physiology, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
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18
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Zhao H, Jiao W, Cui K, Fan X, Shu C, Zhang W, Cao J, Jiang W. Near-freezing temperature storage enhances chilling tolerance in nectarine fruit through its regulation of soluble sugars and energy metabolism. Food Chem 2019; 289:426-435. [PMID: 30955633 DOI: 10.1016/j.foodchem.2019.03.088] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 03/11/2019] [Accepted: 03/18/2019] [Indexed: 12/31/2022]
Abstract
To avoid chilling injury (CI) of nectarines during storage, the impact of near-freezing temperature (NFT) (-1.4 ± 0.1 °C), 0 ± 0.1 °C and 5 ± 0.1 °C on CI incidence, ion leakage, levels of soluble sugars and enzymatic activities related to soluble sugars and energy metabolism, were investigated over five weeks. NFT-stored fruit showed no CI symptoms and significantly (P < 0.05) lower increase of ion leakage than those kept at 0 and 5 °C. NFT significantly (P < 0.05) diminished the activities of sucrose metabolism-associated enzymes leading to a higher level of sucrose in fruit, and maintained higher activities of hexokinase and fructokinase. Additionally, NFT-stored fruit exhibited significantly (P < 0.05) higher activities of energy metabolism-associated enzymes than fruit stored at 0 and 5 °C, leading to high levels of adenosine triphosphate and energy in fruit. These results indicated that NFT storage can effectively enhance chilling tolerance of nectarine fruit by inducing the metabolism of soluble carbohydrates and energy.
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Affiliation(s)
- Handong Zhao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China
| | - Wenxiao Jiao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China
| | - Kuanbo Cui
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China; Agricultural Mechanization Institute, Xinjiang Academy of Agricultural Sciences, No. 291 Nanchangnanlu, Urumqi 830091, PR China
| | - Xinguang Fan
- College of Food Engineering, Ludong University, Yantai 264025, PR China
| | - Chang Shu
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China
| | - Wangli Zhang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China
| | - Jiankang Cao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China
| | - Weibo Jiang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China.
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19
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Wu Y, Hu Q, Li Z, Pei F, Mugambi Mariga A, Yang W. Effect of nanocomposite-based packaging on microstructure and energy metabolism of Agaricus bisporus. Food Chem 2019; 276:790-796. [DOI: 10.1016/j.foodchem.2018.10.088] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 10/16/2018] [Accepted: 10/18/2018] [Indexed: 02/06/2023]
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20
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Dourado DFAR, Swart M, Carvalho ATP. Why the Flavin Adenine Dinucleotide (FAD) Cofactor Needs To Be Covalently Linked to Complex II of the Electron-Transport Chain for the Conversion of FADH 2 into FAD. Chemistry 2017; 24:5246-5252. [PMID: 29124817 PMCID: PMC5969107 DOI: 10.1002/chem.201704622] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 11/07/2017] [Indexed: 11/10/2022]
Abstract
A covalently bound flavin cofactor is predominant in the succinate‐ubiquinone oxidoreductase (SQR; Complex II), an essential component of aerobic electron transport, and in the menaquinol‐fumarate oxidoreductase (QFR), the anaerobic counterpart, although it is only present in approximately 10 % of the known flavoenzymes. This work investigates the role of this 8α‐N3‐histidyl linkage between the flavin adenine dinucleotide (FAD) cofactor and the respiratory Complex II. After parameterization with DFT calculations, classical molecular‐dynamics simulations and quantum‐mechanics calculations for Complex II:FAD and Complex II:FADH2, with and without the covalent bond, were performed. It was observed that the covalent bond is essential for the active‐center arrangement of the FADH2/FAD cofactor. Removal of this bond causes a displacement of the isoalloxazine group, which influences interactions with the protein, flavin solvation, and possible proton‐transfer pathways. Specifically, for the noncovalently bound FADH2 cofactor, the N1 atom moves away from the His‐A365 and His‐A254 residues and the N5 atom moves away from the glutamine‐62A residue. Both of the histidine and glutamine residues interact with a chain of water molecules that cross the enzyme, which is most likely involved in proton transfer. Breaking this chain of water molecules could thereby compromise proton transfer across the two active sites of Complex II.
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Affiliation(s)
- Daniel F A R Dourado
- School of Chemistry and Chemical Engineering, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast, BT9 5AG, Northern Ireland, UK.,Almac Sciences, Department of Biocatalysis and Isotope Chemistry, Almac House, 20 Seagoe Industrial Estate, Craigavon, BT63 5QD, Northern Ireland, UK
| | - Marcel Swart
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, 17003, Girona, Spain.,ICREA, Pg. Lluís Companys 23, 08010, Barcelona, Spain
| | - Alexandra T P Carvalho
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504, Coimbra, Portugal
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21
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Song H, Wang X, Hu W, Yang X, Diao E, Shen T, Qiang Q. A cold-induced phytosulfokine peptide is related to the improvement of loquat fruit chilling tolerance. Food Chem 2017; 232:434-442. [DOI: 10.1016/j.foodchem.2017.04.045] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 03/21/2017] [Accepted: 04/06/2017] [Indexed: 12/31/2022]
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22
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Villa RF, Ferrari F, Bagini L, Gorini A, Brunello N, Tascedda F. Mitochondrial energy metabolism of rat hippocampus after treatment with the antidepressants desipramine and fluoxetine. Neuropharmacology 2017; 121:30-38. [DOI: 10.1016/j.neuropharm.2017.04.025] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Revised: 04/10/2017] [Accepted: 04/14/2017] [Indexed: 01/26/2023]
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23
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Brand MD. Mitochondrial generation of superoxide and hydrogen peroxide as the source of mitochondrial redox signaling. Free Radic Biol Med 2016; 100:14-31. [PMID: 27085844 DOI: 10.1016/j.freeradbiomed.2016.04.001] [Citation(s) in RCA: 668] [Impact Index Per Article: 83.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Revised: 04/02/2016] [Accepted: 04/06/2016] [Indexed: 02/07/2023]
Abstract
This review examines the generation of reactive oxygen species by mammalian mitochondria, and the status of different sites of production in redox signaling and pathology. Eleven distinct mitochondrial sites associated with substrate oxidation and oxidative phosphorylation leak electrons to oxygen to produce superoxide or hydrogen peroxide: oxoacid dehydrogenase complexes that feed electrons to NAD+; respiratory complexes I and III, and dehydrogenases, including complex II, that use ubiquinone as acceptor. The topologies, capacities, and substrate dependences of each site have recently clarified. Complex III and mitochondrial glycerol 3-phosphate dehydrogenase generate superoxide to the external side of the mitochondrial inner membrane as well as the matrix, the other sites generate superoxide and/or hydrogen peroxide exclusively in the matrix. These different site-specific topologies are important for redox signaling. The net rate of superoxide or hydrogen peroxide generation depends on the substrates present and the antioxidant systems active in the matrix and cytosol. The rate at each site can now be measured in complex substrate mixtures. In skeletal muscle mitochondria in media mimicking muscle cytosol at rest, four sites dominate, two in complex I and one each in complexes II and III. Specific suppressors of two sites have been identified, the outer ubiquinone-binding site in complex III (site IIIQo) and the site in complex I active during reverse electron transport (site IQ). These suppressors prevent superoxide/hydrogen peroxide production from a specific site without affecting oxidative phosphorylation, making them excellent tools to investigate the status of the sites in redox signaling, and to suppress the sites to prevent pathologies. They allow the cellular roles of mitochondrial superoxide/hydrogen peroxide production to be investigated without catastrophic confounding bioenergetic effects. They show that sites IIIQo and IQ are active in cells and have important roles in redox signaling (e.g. hypoxic signaling and ER-stress) and in causing oxidative damage in a variety of biological contexts.
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Affiliation(s)
- Martin D Brand
- Buck Institute for Research on Aging, Novato, CA 94945, United States.
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24
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Grivennikova VG, Kozlovsky VS, Vinogradov AD. Respiratory complex II: ROS production and the kinetics of ubiquinone reduction. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1858:109-117. [PMID: 27810396 DOI: 10.1016/j.bbabio.2016.10.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 09/29/2016] [Accepted: 10/28/2016] [Indexed: 11/26/2022]
Abstract
Bovine heart mitochondrial respiratory complex II generates ROS, mostly as superoxide, at the rate of about 20% of that detected during simultaneous operation of complex I and II when oxidation of ubiquinol is prevented by myxothiazol. ROS generating activity at different fumarate/succinate concentrations ratio implies that an enzyme component with a midpoint potential 40mV more positive than that of fumarate/succinate couple is the donor for one-electron reduction of oxygen. This suggests that the iron-sulfur cluster(s) is(are) involved in superoxide formation. Complex II-mediated ROS production exhibits a maximum at low (about 50μM) succinate concentration and gradually declines to zero activity upon further increase of the substrate. This phenomenology is explained and kinetically modeled to suggest a ping-pong mechanism of ROS generating activity where only dicarboxylate free reduced enzyme is oxidized by oxygen. The succinate:quinone reductase activity catalyzed by purified succinate:ubiquinone reductase also exhibits a ping-pong mechanism where only dicarboxylate free enzyme is oxidized by added quinone. Together these data suggest long distance interaction between the succinate (fumarate) binding and ubiquinone (ubiquinol) reactive sites.
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Affiliation(s)
- Vera G Grivennikova
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119991, Russian Federation
| | - Vladimir S Kozlovsky
- Belozersky Institute of Physical-Chemical Biology, Moscow State University, Moscow 119991, Russian Federation
| | - Andrei D Vinogradov
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119991, Russian Federation.
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25
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Differential susceptibility of mitochondrial complex II to inhibition by oxaloacetate in brain and heart. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1561-1568. [PMID: 27287543 PMCID: PMC4990131 DOI: 10.1016/j.bbabio.2016.06.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 05/16/2016] [Accepted: 06/04/2016] [Indexed: 02/06/2023]
Abstract
Mitochondrial Complex II is a key mitochondrial enzyme connecting the tricarboxylic acid (TCA) cycle and the electron transport chain. Studies of complex II are clinically important since new roles for this enzyme have recently emerged in cell signalling, cancer biology, immune response and neurodegeneration. Oxaloacetate (OAA) is an intermediate of the TCA cycle and at the same time is an inhibitor of complex II with high affinity (Kd ~ 10− 8 M). Whether or not OAA inhibition of complex II is a physiologically relevant process is a significant, but still controversial topic. We found that complex II from mouse heart and brain tissue has similar affinity to OAA and that only a fraction of the enzyme in isolated mitochondrial membranes (30.2 ± 6.0% and 56.4 ± 5.6% in the heart and brain, respectively) is in the free, active form. Since OAA could bind to complex II during isolation, we established a novel approach to deplete OAA in the homogenates at the early stages of isolation. In heart, this treatment significantly increased the fraction of free enzyme, indicating that OAA binds to complex II during isolation. In brain the OAA-depleting system did not significantly change the amount of free enzyme, indicating that a large fraction of complex II is already in the OAA-bound inactive form. Furthermore, short-term ischemia resulted in a dramatic decline of OAA in tissues, but it did not change the amount of free complex II. Our data show that in brain OAA is an endogenous effector of complex II, potentially capable of modulating the activity of the enzyme. Complex II in mitochondrial membranes is inhibited by tightly-bound oxaloacetate. Oxaloacetate binds to the heart enzyme during isolation. In brain a large fraction of Complex II is present in oxaloacetate-bound form. Short-time tissue ischemia does not affect the content of the free Complex II in brain.
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26
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Horton JL, Martin OJ, Lai L, Riley NM, Richards AL, Vega RB, Leone TC, Pagliarini DJ, Muoio DM, Bedi KC, Margulies KB, Coon JJ, Kelly DP. Mitochondrial protein hyperacetylation in the failing heart. JCI Insight 2016; 2. [PMID: 26998524 DOI: 10.1172/jci.insight.84897] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Myocardial fuel and energy metabolic derangements contribute to the pathogenesis of heart failure. Recent evidence implicates posttranslational mechanisms in the energy metabolic disturbances that contribute to the pathogenesis of heart failure. We hypothesized that accumulation of metabolite intermediates of fuel oxidation pathways drives posttranslational modifications of mitochondrial proteins during the development of heart failure. Myocardial acetylproteomics demonstrated extensive mitochondrial protein lysine hyperacetylation in the early stages of heart failure in well-defined mouse models and the in end-stage failing human heart. To determine the functional impact of increased mitochondrial protein acetylation, we focused on succinate dehydrogenase A (SDHA), a critical component of both the tricarboxylic acid (TCA) cycle and respiratory complex II. An acetyl-mimetic mutation targeting an SDHA lysine residue shown to be hyperacetylated in the failing human heart reduced catalytic function and reduced complex II-driven respiration. These results identify alterations in mitochondrial acetyl-CoA homeostasis as a potential driver of the development of energy metabolic derangements that contribute to heart failure.
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Affiliation(s)
- Julie L Horton
- Cardiovascular Metabolism Program, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida, USA
| | - Ola J Martin
- Cardiovascular Metabolism Program, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida, USA
| | - Ling Lai
- Cardiovascular Metabolism Program, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida, USA
| | - Nicholas M Riley
- Department of Chemistry, University of Wisconsin - Madison, Madison, Wisconsin, USA; Genome Center of Wisconsin, University of Wisconsin - Madison, Madison, Wisconsin, USA
| | - Alicia L Richards
- Department of Chemistry, University of Wisconsin - Madison, Madison, Wisconsin, USA; Genome Center of Wisconsin, University of Wisconsin - Madison, Madison, Wisconsin, USA
| | - Rick B Vega
- Cardiovascular Metabolism Program, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida, USA
| | - Teresa C Leone
- Cardiovascular Metabolism Program, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida, USA
| | - David J Pagliarini
- Department of Biochemistry, University of Wisconsin - Madison, Madison, Wisconsin, USA
| | - Deborah M Muoio
- Departments of Medicine, Pharmacology, and Cancer Biology, Duke University, Durham, North Carolina, USA
| | - Kenneth C Bedi
- Cardiovascular Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kenneth B Margulies
- Cardiovascular Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Joshua J Coon
- Department of Chemistry, University of Wisconsin - Madison, Madison, Wisconsin, USA; Genome Center of Wisconsin, University of Wisconsin - Madison, Madison, Wisconsin, USA; Department of Biomolecular Chemistry, University of Wisconsin - Madison, Madison, Wisconsin, USA
| | - Daniel P Kelly
- Cardiovascular Metabolism Program, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida, USA
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27
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Alleviation of chilling injury in tomato fruit by exogenous application of oxalic acid. Food Chem 2016; 202:125-32. [PMID: 26920276 DOI: 10.1016/j.foodchem.2016.01.142] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 01/10/2016] [Accepted: 01/29/2016] [Indexed: 11/23/2022]
Abstract
The effects of oxalic acid on the development of chilling injury (CI), energy metabolism and lycopene metabolism in tomato fruit (Solanum lycopersicum L.) were investigated. Mature green tomatoes were dipped in 10mmoll(-1) oxalic acid (OA) solution for 10min at 25°C. Tomatoes were subsequently stored at 4±0.5°C for 20days before being transferred to 25°C for 12days. Oxalic acid treatment apparently alleviated CI development and membrane damage; maintained higher levels of ATP and ADP; increased activities of succinic dehydrogenase (SDH), Ca(2+)-adenosine triphosphatase (Ca(2+)-ATPase) and H(+)-adenosine triphosphatase (H(+)-ATPase); and elevated lycopene accumulation associated with the upregulation of PSY1 and ZDS expression in tomatoes during a period at room temperature following exposure to chilling stress. Thus, oxalic acid treatment benefited the control of CI and the maintenance of fruit quality in tomatoes stored for long periods (approximately 32days).
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28
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Jin P, Zhang Y, Shan T, Huang Y, Xu J, Zheng Y. Low-temperature conditioning alleviates chilling injury in loquat fruit and regulates glycine betaine content and energy status. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:3654-9. [PMID: 25822129 DOI: 10.1021/acs.jafc.5b00605] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The influence of low-temperature conditioning (LTC) treatment on chilling injury, glycine betaine content, and energy metabolism in loquat fruit at 1 °C storage was investigated. The results indicated that LTC treatment significantly reduced chilling injury index, ion leakage, and malondialdehyde content in loquat fruit. Betaine aldehyde hydrogenase (BADH) activity and endogenous glycine betaine (GB) content in loquats treated with LTC were significantly higher than those in control fruit. Moreover, LTC treatment induced activities of energy metabolism-associated enzymes, including H(+)-adenosine triphosphatase, Ca(2+)-adenosine triphosphatase, succinic dehydrogenase, and cytochrome c oxidase. LTC treatment triggered obviously higher levels of adenosine triphosphate (ATP) content and energy charge in loquat fruit. These results showed that LTC possibly alleviated chilling injury and enhanced chilling tolerance of loquat fruit by enhancing endogenous GB content and energy status.
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Affiliation(s)
- Peng Jin
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Yu Zhang
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Timin Shan
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Yuping Huang
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Jia Xu
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Yonghua Zheng
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
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The influence of oxygen limitation for the production of succinic acid with recombinant strains of Yarrowia lipolytica. Appl Microbiol Biotechnol 2014; 99:1675-86. [DOI: 10.1007/s00253-014-6252-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 11/17/2014] [Accepted: 11/18/2014] [Indexed: 01/13/2023]
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Wang Y, Wang Y, Marcus S, Busenlehner LS. The role of frataxin in fission yeast iron metabolism: implications for Friedreich's ataxia. BIOCHIMICA ET BIOPHYSICA ACTA 2014; 1840:3022-33. [PMID: 24997422 DOI: 10.1016/j.bbagen.2014.06.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 06/25/2014] [Accepted: 06/26/2014] [Indexed: 01/01/2023]
Abstract
BACKGROUND The neurodegenerative disease Friedreich's ataxia is the result of frataxin deficiency. Frataxin is a mitochondrial protein involved in iron-sulfur cluster (Fe-S) cofactor biogenesis, but its functional role in this pathway is debated. This is due to the interconnectivity of iron metabolic and oxidative stress response pathways that make distinguishing primary effects of frataxin deficiency challenging. Since Fe-S cluster assembly is conserved, frataxin overexpression phenotypes in a simple eukaryotic organism will provide additional insight into frataxin function. METHODS The Schizosaccharomyces pombe frataxin homologue (fxn1) was overexpressed from a plasmid under a thiamine repressible promoter. The S. pombe transformants were characterized at several expression strengths for cellular growth, mitochondrial organization, iron levels, oxidative stress, and activities of Fe-S cluster containing enzymes. RESULTS Observed phenotypes were dependent on the amount of Fxn1 overexpression. High Fxn1 overexpression severely inhibited S. pombe growth, impaired mitochondrial membrane integrity and cellular respiration, and led to Fxn1 aggregation. Cellular iron accumulation was observed at moderate Fxn1 overexpression but was most pronounced at high levels of Fxn1. All levels of Fxn1 overexpression up-regulated oxidative stress defense and mitochondrial Fe-S cluster containing enzyme activities. CONCLUSIONS Despite the presence of oxidative stress and accumulated iron, activation of Fe-S cluster enzymes was common to all levels of Fxn1 overexpression; therefore, Fxn1 may regulate the efficiency of Fe-S cluster biogenesis in S. pombe. GENERAL SIGNIFICANCE We provide evidence that suggests that dysregulated Fe-S cluster biogenesis is a primary effect of both frataxin overexpression and deficiency as in Friedreich's ataxia.
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Affiliation(s)
- Yu Wang
- Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Yiwei Wang
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - S Marcus
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL 35487, USA.
| | - L S Busenlehner
- Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487, USA.
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Essentiality of succinate dehydrogenase in Mycobacterium smegmatis and its role in the generation of the membrane potential under hypoxia. mBio 2014; 5:mBio.01093-14. [PMID: 25118234 PMCID: PMC4145680 DOI: 10.1128/mbio.01093-14] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Succinate:quinone oxidoreductase (Sdh) is a membrane-bound complex that couples the oxidation of succinate to fumarate in the cytoplasm to the reduction of quinone to quinol in the membrane. Mycobacterial species harbor genes for two putative sdh operons, but the individual roles of these two operons are unknown. In this communication, we show that Mycobacterium smegmatis mc2155 expresses two succinate dehydrogenases designated Sdh1 and Sdh2. Sdh1 is encoded by a five-gene operon (MSMEG_0416-MSMEG_0420), and Sdh2 is encoded by a four-gene operon (MSMEG_1672-MSMEG_1669). These two operons are differentially expressed in response to carbon limitation, hypoxia, and fumarate, as monitored by sdh promoter-lacZ fusions. While deletion of the sdh1 operon did not yield any growth phenotypes on succinate or other nonfermentable carbon sources, the sdh2 operon could be deleted only in a merodiploid background, demonstrating that Sdh2 is essential for growth. Sdh activity and succinate-dependent proton pumping were detected in cells grown aerobically, as well as under hypoxia. Fumarate reductase activity was absent under these conditions, indicating that neither Sdh1 nor Sdh2 could catalyze the reverse reaction. Sdh activity was inhibited by the Sdh inhibitor 3-nitroproprionate (3NP), and treatment with 3NP dissipated the membrane potential of wild-type or Δsdh1 mutant cells under hypoxia but not that of cells grown aerobically. These data imply that Sdh2 is the generator of the membrane potential under hypoxia, an essential role for the cell. Complex II or succinate dehydrogenase (Sdh) is a major respiratory enzyme that couples the oxidation of succinate to fumarate in the cytoplasm to the reduction of quinone to quinol in the membrane. Mycobacterial species harbor genes for two putative sdh operons, sdh1 and sdh2, but the individual roles of these two operons are unknown. In this communication, we show that sdh1 and sdh2 are differentially expressed in response to energy limitation, oxygen tension, and alternative electron acceptor availability, suggesting distinct functional cellular roles. Sdh2 was essential for growth and generation of the membrane potential in hypoxic cells. Given the essentiality of succinate dehydrogenase and oxidative phosphorylation in the growth cycle of Mycobacterium tuberculosis, the potential exists to develop new antituberculosis agents against the mycobacterial succinate dehydrogenase. This enzyme has been proposed as a potential target for the development of new chemotherapeutic agents against intracellular parasites and mitochondrion-associated disease.
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Wang L, Hou E, Wang Z, Sun N, He L, Chen L, Liang M, Tian Z. Analysis of metabolites in plasma reveals distinct metabolic features between Dahl salt-sensitive rats and consomic SS.13(BN) rats. Biochem Biophys Res Commun 2014; 450:863-9. [PMID: 24971531 DOI: 10.1016/j.bbrc.2014.06.089] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Accepted: 06/17/2014] [Indexed: 11/26/2022]
Abstract
Salt-sensitive hypertension is a major risk factor for cardiovascular disorders. Our previous proteomic study revealed substantial differences in several proteins between Dahl salt-sensitive (SS) rats and salt-insensitive consomic SS.13(BN) rats. Subsequent experiments indicated a role of fumarase insufficiency in the development of hypertension in SS rats. In the present study, a global metabolic profiling study was performed using gas chromatography/mass spectrometry (GC/MS) in plasma of SS rats (n=9) and SS.13(BN) rats (n=8) on 0.4% NaCl diet, designed to gain further insights into the relationship between alterations in cellular intermediary metabolism and predisposition to hypertension. Principal component analysis of the data sets revealed a clear clustering and separation of metabolic profiles between SS rats and SS.13(BN) rats. 23 differential metabolites were identified (P<0.05). Higher levels of five TCA cycle metabolites, fumarate, cis-aconitate, isocitrate, citrate and succinate, were observed in SS rats. Pyruvate, which connects TCA cycle and glycolysis, was also increased in SS rats. Moreover, lower activity levels of fumarase, aconitase, α-ketoglutarate dehydrogenase and succinyl-CoA synthetase were detected in the heart, liver or skeletal muscles of SS rats. The distinct metabolic features in SS and SS.13(BN) rats indicate abnormalities of TCA cycle in SS rats, which may play a role in predisposing SS rats to developing salt-sensitive hypertension.
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Affiliation(s)
- Le Wang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Entai Hou
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Zhengjun Wang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Na Sun
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Liqing He
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Lan Chen
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Mingyu Liang
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States
| | - Zhongmin Tian
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China.
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Bienholz A, Al-Taweel A, Roeser NF, Kribben A, Feldkamp T, Weinberg JM. Substrate modulation of fatty acid effects on energization and respiration of kidney proximal tubules during hypoxia/reoxygenation. PLoS One 2014; 9:e94584. [PMID: 24728405 PMCID: PMC3984175 DOI: 10.1371/journal.pone.0094584] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 03/17/2014] [Indexed: 12/03/2022] Open
Abstract
Kidney proximal tubules subjected to hypoxia/reoxygenation develop a nonesterified fatty acid-induced energetic deficit characterized by persistent partial mitochondrial deenergization that can be prevented and reversed by citric acid cycle substrates. To further assess the role of competition between fatty acids and substrates on inner membrane substrate carriers in the deenergization and the contribution to deenergization of fatty acid effects on respiratory function, digitonin-permeabilized rabbit and mouse tubules were studied using either addition of exogenous oleate after control normoxic incubation or increases of endogenous fatty acids produced by hypoxia/reoxygenation. The results demonstrated major effects of matrix oxaloacetate accumulation on succinate-supported energization and respiration and their modification by fatty acids. Improvements of energization in the presence of fatty acids by glutamate were shown to result predominantly from lowering matrix oxaloacetate rather than from amelioration of transmembrane cycling of fatty acids and uncoupling. Mouse tubules had 2.5 fold higher rates of succinate utilization, which resulted in stronger effects of oxaloacetate accumulation than rabbit tubules. Hypoxia/reoxygenation induced respiratory inhibition that was more severe for complex I-dependent substrates. Fatty acids themselves did not acutely contribute to this respiratory inhibition, but lowering them during 60 min. reoxygenation to allow recovery of ATP during that period alleviated it. These data clarify the basis for the nonesterified fatty acid-induced mitochondrial energetic deficit in kidney proximal tubules that impairs structural and functional recovery and provide insight into interactions that need to be considered in the design of substrate-based interventions to improve mitochondrial function.
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Affiliation(s)
- Anja Bienholz
- Division of Nephrology, Department of Internal Medicine, Veterans Affairs Ann Arbor Healthcare System and University of Michigan, Ann Arbor, Michigan, United States of America
- Division of Nephrology, Department of Internal Medicine, University Duisburg-Essen, Essen, Germany
| | - Ahmad Al-Taweel
- Division of Nephrology, Department of Internal Medicine, Veterans Affairs Ann Arbor Healthcare System and University of Michigan, Ann Arbor, Michigan, United States of America
| | - Nancy F. Roeser
- Division of Nephrology, Department of Internal Medicine, Veterans Affairs Ann Arbor Healthcare System and University of Michigan, Ann Arbor, Michigan, United States of America
| | - Andreas Kribben
- Division of Nephrology, Department of Internal Medicine, University Duisburg-Essen, Essen, Germany
| | - Thorsten Feldkamp
- Division of Nephrology, Department of Internal Medicine, Veterans Affairs Ann Arbor Healthcare System and University of Michigan, Ann Arbor, Michigan, United States of America
- Division of Nephrology, Department of Internal Medicine, University Duisburg-Essen, Essen, Germany
- Division of Nephrology and Hypertension, Department of Internal Medicine, Christian-Albrechts-University, Kiel, Germany
| | - Joel M. Weinberg
- Division of Nephrology, Department of Internal Medicine, Veterans Affairs Ann Arbor Healthcare System and University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail:
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Oxalic acid alleviates chilling injury in peach fruit by regulating energy metabolism and fatty acid contents. Food Chem 2014; 161:87-93. [PMID: 24837925 DOI: 10.1016/j.foodchem.2014.03.103] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 03/18/2014] [Accepted: 03/20/2014] [Indexed: 11/20/2022]
Abstract
The effects of postharvest oxalic acid (OA) treatment on chilling injury, energy metabolism and membrane fatty acid content in 'Baifeng' peach fruit stored at 0°C were investigated. Internal browning was significantly reduced by OA treatment in peaches. OA treatment markedly inhibited the increase of ion leakage and the accumulation of malondialdehyde. Meanwhile, OA significantly increased the contents of adenosine triphosphate and energy charge in peach fruit. Enzyme activities of energy metabolism including H(+)-adenosine triphosphatase, Ca(2+)-adenosine triphosphatase, succinic dehydrogenase and cytochrome C oxidase were markedly enhanced by OA treatment. The ratio of unsaturated/saturated fatty acid in OA-treated fruit was significantly higher than that in control fruit. These results suggest that the alleviation in chilling injury by OA may be due to enhanced enzyme activities related to energy metabolism and higher levels of energy status and unsaturated/saturated fatty acid ratio.
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35
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Liang X, Qin L, Liu P, Wang M, Ye H. Genes for iron-sulphur cluster assembly are targets of abiotic stress in rice, Oryza sativa. PLANT, CELL & ENVIRONMENT 2014; 37:780-94. [PMID: 24028141 DOI: 10.1111/pce.12198] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 08/27/2013] [Accepted: 09/01/2013] [Indexed: 05/14/2023]
Abstract
Iron-sulphur (Fe-S) cluster assembly occurs in chloroplasts, mitochondria and cytosol, involving dozens of genes in higher plants. In this study, we have identified 41 putative Fe-S cluster assembly genes in rice (Oryza sativa) genome, and the expression of all genes was verified. To investigate the role of Fe-S cluster assembly as a metabolic pathway, we applied abiotic stresses to rice seedlings and analysed Fe-S cluster assembly gene expression by qRT-PCR. Our data showed that genes for Fe-S cluster assembly in chloroplasts of leaves are particularly sensitive to heavy metal treatments, and that Fe-S cluster assembly genes in roots were up-regulated in response to iron toxicity, oxidative stress and some heavy metal assault. The effect of each stress treatment on the Fe-S cluster assembly machinery demonstrated an unexpected tissue or organelle specificity, suggesting that the physiological relevance of the Fe-S cluster assembly is more complex than thought. Furthermore, our results may reveal potential candidate genes for molecular breeding of rice.
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Affiliation(s)
- Xuejiao Liang
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China
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36
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Mráček T, Holzerová E, Drahota Z, Kovářová N, Vrbacký M, Ješina P, Houštěk J. ROS generation and multiple forms of mammalian mitochondrial glycerol-3-phosphate dehydrogenase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:98-111. [DOI: 10.1016/j.bbabio.2013.08.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 08/20/2013] [Accepted: 08/25/2013] [Indexed: 01/10/2023]
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37
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Caesium accumulation in yeast and plants is selectively repressed by loss of the SNARE Sec22p/SEC22. Nat Commun 2013; 4:2092. [DOI: 10.1038/ncomms3092] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Accepted: 05/31/2013] [Indexed: 11/08/2022] Open
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38
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Damiano M, Diguet E, Malgorn C, D'Aurelio M, Galvan L, Petit F, Benhaim L, Guillermier M, Houitte D, Dufour N, Hantraye P, Canals JM, Alberch J, Delzescaux T, Déglon N, Beal MF, Brouillet E. A role of mitochondrial complex II defects in genetic models of Huntington's disease expressing N-terminal fragments of mutant huntingtin. Hum Mol Genet 2013; 22:3869-82. [PMID: 23720495 PMCID: PMC3766181 DOI: 10.1093/hmg/ddt242] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Huntington's disease (HD) is a neurodegenerative disorder caused by an abnormal expansion of a CAG repeat encoding a polyglutamine tract in the huntingtin (Htt) protein. The mutation leads to neuronal death through mechanisms which are still unknown. One hypothesis is that mitochondrial defects may play a key role. In support of this, the activity of mitochondrial complex II (C-II) is preferentially reduced in the striatum of HD patients. Here, we studied C-II expression in different genetic models of HD expressing N-terminal fragments of mutant Htt (mHtt). Western blot analysis showed that the expression of the 30 kDa Iron–Sulfur (Ip) subunit of C-II was significantly reduced in the striatum of the R6/1 transgenic mice, while the levels of the FAD containing catalytic 70 kDa subunit (Fp) were not significantly changed. Blue native gel analysis showed that the assembly of C-II in mitochondria was altered early in N171-82Q transgenic mice. Early loco-regional reduction in C-II activity and Ip protein expression was also demonstrated in a rat model of HD using intrastriatal injection of lentiviral vectors encoding mHtt. Infection of the rat striatum with a lentiviral vector coding the C-II Ip or Fp subunits induced a significant overexpression of these proteins that led to significant neuroprotection of striatal neurons against mHtt neurotoxicity. These results obtained in vivo support the hypothesis that structural and functional alterations of C-II induced by mHtt may play a critical role in the degeneration of striatal neurons in HD and that mitochondrial-targeted therapies may be useful in its treatment.
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Affiliation(s)
- Maria Damiano
- The first two authors contributed equally to the present study
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39
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Dröse S. Differential effects of complex II on mitochondrial ROS production and their relation to cardioprotective pre- and postconditioning. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:578-87. [DOI: 10.1016/j.bbabio.2013.01.004] [Citation(s) in RCA: 139] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 01/04/2013] [Accepted: 01/09/2013] [Indexed: 11/30/2022]
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40
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Defining a direction: electron transfer and catalysis in Escherichia coli complex II enzymes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:668-78. [PMID: 23396003 DOI: 10.1016/j.bbabio.2013.01.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 01/23/2013] [Accepted: 01/23/2013] [Indexed: 11/24/2022]
Abstract
There are two homologous membrane-bound enzymes in Escherichia coli that catalyze reversible conversion between succinate/fumarate and quinone/quinol. Succinate:ubiquinone reductase (SQR) is a component of aerobic respiratory chains, whereas quinol:fumarate reductase (QFR) utilizes menaquinol to reduce fumarate in a final step of anaerobic respiration. Although, both protein complexes are capable of supporting bacterial growth on either minimal succinate or fumarate media, the enzymes are more proficient in their physiological directions. Here we evaluate factors that may underlie this catalytic bias. This article is part of a Special Issue entitled: Respiratory complex II: Role in cellular physiology and disease.
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41
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Baron JA, Laws KM, Chen JS, Culotta VC. Superoxide triggers an acid burst in Saccharomyces cerevisiae to condition the environment of glucose-starved cells. J Biol Chem 2012; 288:4557-66. [PMID: 23281478 DOI: 10.1074/jbc.m112.409508] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although yeast cells grown in abundant glucose tend to acidify their extracellular environment, they raise the pH of the environment when starved for glucose or when grown strictly with non-fermentable carbon sources. Following prolonged periods in this alkaline phase, Saccharomyces cerevisiae cells will switch to producing acid. The mechanisms and rationale for this "acid burst" were unknown. Herein we provide strong evidence for the role of mitochondrial superoxide in initiating the acid burst. Yeast mutants lacking the mitochondrial matrix superoxide dismutase (SOD2) enzyme, but not the cytosolic Cu,Zn-SOD1 enzyme, exhibited marked acceleration in production of acid on non-fermentable carbon sources. Acid production is also dramatically enhanced by the superoxide-producing agent, paraquat. Conversely, the acid burst is eliminated by boosting cellular levels of Mn-antioxidant mimics of SOD. We demonstrate that the acid burst is dependent on the mitochondrial aldehyde dehydrogenase Ald4p. Our data are consistent with a model in which mitochondrial superoxide damage to Fe-S enzymes in the tricarboxylic acid (TCA) cycle leads to acetate buildup by Ald4p. The resultant expulsion of acetate into the extracellular environment can provide a new carbon source to glucose-starved cells and enhance growth of yeast. By triggering production of organic acids, mitochondrial superoxide has the potential to promote cell population growth under nutrient depravation stress.
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Affiliation(s)
- J Allen Baron
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland 21205, USA
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42
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Quinlan CL, Orr AL, Perevoshchikova IV, Treberg JR, Ackrell BA, Brand MD. Mitochondrial complex II can generate reactive oxygen species at high rates in both the forward and reverse reactions. J Biol Chem 2012; 287:27255-64. [PMID: 22689576 DOI: 10.1074/jbc.m112.374629] [Citation(s) in RCA: 484] [Impact Index Per Article: 40.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Respiratory complex II oxidizes succinate to fumarate as part of the Krebs cycle and reduces ubiquinone in the electron transport chain. Previous experimental evidence suggested that complex II is not a significant contributor to the production of reactive oxygen species (ROS) in isolated mitochondria or intact cells unless mutated. However, we find that when complex I and complex III are inhibited and succinate concentration is low, complex II in rat skeletal muscle mitochondria can generate superoxide or H(2)O(2) at high rates. These rates approach or exceed the maximum rates achieved by complex I or complex III. Complex II generates these ROS in both the forward reaction, with electrons supplied by succinate, and the reverse reaction, with electrons supplied from the reduced ubiquinone pool. ROS production in the reverse reaction is prevented by inhibition of complex II at either the ubiquinone-binding site (by atpenin A5) or the flavin (by malonate), whereas ROS production in the forward reaction is prevented by malonate but not by atpenin A5, showing that the ROS from complex II arises only from the flavin site (site II(F)). We propose a mechanism for ROS production by complex II that relies upon the occupancy of the substrate oxidation site and the reduction state of the enzyme. We suggest that complex II may be an important contributor to physiological and pathological ROS production.
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Affiliation(s)
- Casey L Quinlan
- Buck Institute for Research on Aging, Novato, California 94945, USA.
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Miyamoto E, Tanioka Y, Nishizawa-Yokoi A, Yabuta Y, Ohnishi K, Misono H, Shigeoka S, Nakano Y, Watanabe F. Characterization of methylmalonyl-CoA mutase involved in the propionate photoassimilation of Euglena gracilis Z. Arch Microbiol 2010; 192:437-46. [PMID: 20379701 DOI: 10.1007/s00203-010-0572-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Revised: 02/26/2010] [Accepted: 03/24/2010] [Indexed: 11/24/2022]
Affiliation(s)
- Emi Miyamoto
- Department of Health and Nutrition, Nagasaki International University, Sasebo, Japan
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44
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Azarkina NV, Konstantinov AA. Energization of Bacillus subtilis membrane vesicles increases catalytic activity of succinate: Menaquinone oxidoreductase. BIOCHEMISTRY (MOSCOW) 2010; 75:50-62. [DOI: 10.1134/s0006297910010074] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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45
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Varghese M, Pandey M, Samanta A, Gangopadhyay PK, Mohanakumar KP. Reduced NADH coenzyme Q dehydrogenase activity in platelets of Parkinson's disease, but not Parkinson plus patients, from an Indian population. J Neurol Sci 2009; 279:39-42. [DOI: 10.1016/j.jns.2008.12.021] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Revised: 11/25/2008] [Accepted: 12/17/2008] [Indexed: 11/29/2022]
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46
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Abstract
After bleaching of visual pigment in vertebrate photoreceptors, all-trans retinal is reduced to all-trans retinol by retinol dehydrogenases (RDHs). We investigated this reaction in purified carp rods and cones, and we found that the reducing activity toward all-trans retinal in the outer segment (OS) of cones is >30 times higher than that of rods. The high activity of RDHs was attributed to high content of RDH8 in cones. In the inner segment (IS) in both rods and cones, RDH8L2 and RDH13 were found to be the major enzymes among RDH family proteins. We further found a previously undescribed and effective pathway to convert 11-cis retinol to 11-cis retinal in cones: this oxidative conversion did not require NADP(+) and instead was coupled with reduction of all-trans retinal to all-trans retinol. The activity was >50 times effective than the oxidizing activity of RDHs that require NADP(+). These highly effective reactions of removal of all-trans retinal by RDH8 and production of 11-cis retinal by the coupling reaction are probably the underlying mechanisms that ensure effective visual pigment regeneration in cones that function under much brighter light conditions than rods.
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Cohen-Ben-Lulu GN, Francis NR, Shimoni E, Noy D, Davidov Y, Prasad K, Sagi Y, Cecchini G, Johnstone RM, Eisenbach M. The bacterial flagellar switch complex is getting more complex. EMBO J 2008; 27:1134-44. [PMID: 18337747 DOI: 10.1038/emboj.2008.48] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2007] [Accepted: 02/25/2008] [Indexed: 11/09/2022] Open
Abstract
The mechanism of function of the bacterial flagellar switch, which determines the direction of flagellar rotation and is essential for chemotaxis, has remained an enigma for many years. Here we show that the switch complex associates with the membrane-bound respiratory protein fumarate reductase (FRD). We provide evidence that FRD binds to preparations of isolated switch complexes, forms a 1:1 complex with the switch protein FliG, and that this interaction is required for both flagellar assembly and switching the direction of flagellar rotation. We further show that fumarate, known to be a clockwise/switch factor, affects the direction of flagellar rotation through FRD. These results not only uncover a new component important for switching and flagellar assembly, but they also reveal that FRD, an enzyme known to be primarily expressed and functional under anaerobic conditions in Escherichia coli, nonetheless, has important, unexpected functions under aerobic conditions.
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48
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Pandey M, Varghese M, Sindhu KM, Sreetama S, Navneet AK, Mohanakumar KP, Usha R. Mitochondrial NAD+-linked State 3 respiration and complex-I activity are compromised in the cerebral cortex of 3-nitropropionic acid-induced rat model of Huntington's disease. J Neurochem 2007; 104:420-34. [PMID: 17953654 DOI: 10.1111/j.1471-4159.2007.04996.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Mitochondrial complex-I dysfunction has been observed in patients of Huntington's disease (HD). We assessed whether such a defect is present in the 3-nitropropionic acid (3-NP) model of HD. Rats treated with 3-NP (10-20 mg/kg i.p., for 4 days) exhibited weight loss, gait abnormalities, and striatal lesions with increased glial fibrillary acidic protein immunostaining on fifth and ninth days, while increase in striatal dopamine and loss of tyrosine hydroxylase immunoreactivity were observed on fifth day following treatment. We report for the first time a dose-dependent reduction in complex-I activity in the cerebral cortex when analyzed spectrophotometrically and by blue native-polyacrylamide gel electrophoresis following 3-NP treatment. The citrate synthase normalized activities of mitochondrial complex-I, -II, -(I + III) and -IV were decreased in the cortex of 3-NP treated rats. In addition, succinate driven State 3 respiration was also significantly inhibited in vivo and in the isolated mitochondria. These findings taken together with the observation of a significant decrease in vivo but not in vitro of State 3 respiration with NAD(+)-linked substrates, suggest complex-I dysfunction in addition to irreversible inhibition of complex-II and succinate dehydrogenase activity as a contributing factor in 3-NP-induced cortico-striatal lesion.
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Affiliation(s)
- Mritunjay Pandey
- Laboratory of Clinical & Experimental Neuroscience, Division of Cell Biology & Physiology, Indian Institute of Chemical Biology, Kolkata, India
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Zhao Z, Rothery RA, Weiner JH. Effects of site-directed mutations inEscherichia colisuccinate dehydrogenase on the enzyme activity and production of superoxide radicalsThis paper is one of a selection of papers published in this Special Issue, entitled CSBMCB — Membrane Proteins in Health and Disease. Biochem Cell Biol 2006; 84:1013-21. [PMID: 17215887 DOI: 10.1139/o06-188] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Escherichia coli succinate dehydrogenase (SdhCDAB) catalyzes the oxidation of succinate to fumarate in the Krebs cycle, and during turnover, it produces superoxide radicals. SdhCDAB is a good model system for the succinate dehydrogenase (Sdh) found in the mitochondrial respiratory chain (complex II), as the subunits are structural homologues. Although mutations in sdh genes are reportedly associated with a variety of mitochondria-related diseases, the molecular mechanism of these diseases is poorly understood. We have investigated the effects of site-directed mutations around the heme (SdhD-H71L and SdhC-H91L), and at the ubiquinone-binding site (Q site; SdhC-I28E), on enzyme activity and production of superoxide radicals. The mutations SdhD-H71L and SdhC-I28E, but not SdhC-H91L, significantly reduce the succinate–ubiquinone reductase activity of the enzyme. All 3 mutant enzymes produce more superoxide than the wild-type enzyme, indicating that disturbance of the heme or the Q site can enhance superoxide production. The presence of a Q-site inhibitor reduces superoxide production significantly. Furthermore, the yield of superoxide is substrate dependent and increases with succinate concentration from 0.1 to 10 mmol/L. Our results indicate that, in SdhCDAB, the Q site with bound ubiquinone is an important source of superoxide radicals.
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Affiliation(s)
- Zhongwei Zhao
- Membrane Protein Research Group, Department of Biochemistry, 474 Medical Sciences Building, University of Alberta, Edmonton, AB T6G 2H7, Canada
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50
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Shertzer HG, Genter MB, Shen D, Nebert DW, Chen Y, Dalton TP. TCDD decreases ATP levels and increases reactive oxygen production through changes in mitochondrial F(0)F(1)-ATP synthase and ubiquinone. Toxicol Appl Pharmacol 2006; 217:363-74. [PMID: 17109908 PMCID: PMC1783833 DOI: 10.1016/j.taap.2006.09.014] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2006] [Revised: 08/28/2006] [Accepted: 09/27/2006] [Indexed: 01/24/2023]
Abstract
Mitochondria generate ATP and participate in signal transduction and cellular pathology and/or cell death. TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) decreases hepatic ATP levels and generates mitochondrial oxidative DNA damage, which is exacerbated by increasing mitochondrial glutathione redox state and by inner membrane hyperpolarization. This study identifies mitochondrial targets of TCDD that initiate and sustain reactive oxygen production and decreased ATP levels. One week after treating mice with TCDD, liver ubiquinone (Q) levels were significantly decreased, while rates of succinoxidase and Q-cytochrome c oxidoreductase activities were increased. However, the expected increase in Q reduction state following TCDD treatment did not occur; instead, Q was more oxidized. These results could be explained by an ATP synthase defect, a premise supported by the unusual finding that TCDD lowers ATP/O ratios without concomitant changes in respiratory control ratios. Such results suggest either a futile cycle in ATP synthesis, or hydrolysis of newly synthesized ATP prior to release. The TCDD-mediated decrease in Q, concomitant with an increase in respiration, increases complex 3 redox cycling. This acts in concert with glutathione to increase membrane potential and reactive oxygen production. The proposed defect in ATP synthase explains both the greater respiratory rates and the lower tissue ATP levels.
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Affiliation(s)
- Howard G Shertzer
- Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056 Cincinnati, OH 45267-0056, USA.
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