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Rekuviene E, Ivanoviene L, Borutaite V, Morkuniene R. Effects of Anesthesia with Pentobarbital/Ketamine on Mitochondrial Permeability Transition Pore Opening and Ischemic Brain Damage. Biomedicines 2024; 12:2342. [PMID: 39457655 PMCID: PMC11504713 DOI: 10.3390/biomedicines12102342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2024] [Revised: 09/30/2024] [Accepted: 10/08/2024] [Indexed: 10/28/2024] Open
Abstract
BACKGROUND AND OBJECTIVE The alteration of mitochondrial functions, especially the opening of the mitochondrial permeability transition pore (mPTP), has been proposed as a key mechanism in the development of lesions in cerebral ischemia, wherefore it is considered as an important target for drugs against ischemic injury. In this study, we aimed to investigate the effects of mitochondrial complex I inhibitors as possible regulators of mPTP using an in vitro brain ischemia model of the pentobarbital/ketamine (PBK)-anesthetized rats. RESULTS We found that PBK anesthesia itself delayed Ca2+-induced mPTP opening and partially recovered the respiratory functions of mitochondria, isolated from rat brain cortex and cerebellum. In addition, PBK reduced cell death in rat brain slices of cerebral cortex and cerebellum. PBK inhibited the adenosine diphosphate (ADP)-stimulated respiration of isolated cortical and cerebellar mitochondria respiring with complex I-dependent substrates pyruvate and malate. Moreover, pentobarbital alone directly increased the resistance of isolated cortex mitochondria to Ca2+-induced activation of mPTP and inhibited complex I-dependent respiration and mitochondrial complex I activity. In contrast, ketamine had no direct effect on functions of isolated normal cortex and cerebellum mitochondria. CONCLUSIONS Altogether, this suggests that modulation of mitochondrial complex I activity by pentobarbital during PBK anesthesia may increase the resistance of mitochondria to mPTP opening, which is considered the key event in brain cell necrosis during ischemia.
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Affiliation(s)
- Evelina Rekuviene
- Neuroscience Institute, Lithuanian University of Health Sciences, Eiveniu 4, LT-50161 Kaunas, Lithuania; (V.B.); (R.M.)
- Department of Biochemistry, Lithuanian University of Health Sciences, Eiveniu 4, LT-50161 Kaunas, Lithuania;
| | - Laima Ivanoviene
- Department of Biochemistry, Lithuanian University of Health Sciences, Eiveniu 4, LT-50161 Kaunas, Lithuania;
| | - Vilmante Borutaite
- Neuroscience Institute, Lithuanian University of Health Sciences, Eiveniu 4, LT-50161 Kaunas, Lithuania; (V.B.); (R.M.)
- Department of Biochemistry, Lithuanian University of Health Sciences, Eiveniu 4, LT-50161 Kaunas, Lithuania;
| | - Ramune Morkuniene
- Neuroscience Institute, Lithuanian University of Health Sciences, Eiveniu 4, LT-50161 Kaunas, Lithuania; (V.B.); (R.M.)
- Department of Drug Chemistry, Lithuanian University of Health Sciences, Sukileliu 13, LT-50162 Kaunas, Lithuania
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Karadayian AG, Czerniczyniec A, Lores-Arnaiz S. Apoptosis Due to After-effects of Acute Ethanol Exposure in Brain Cortex: Intrinsic and Extrinsic Signaling Pathways. Neuroscience 2024; 544:39-49. [PMID: 38423164 DOI: 10.1016/j.neuroscience.2024.02.022] [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: 11/16/2023] [Revised: 02/21/2024] [Accepted: 02/23/2024] [Indexed: 03/02/2024]
Abstract
Alcohol hangover is the combination of negative mental and physical symptoms which can be experienced after a single episode of alcohol consumption, starting when blood alcohol concentration approaches zero. We previously demonstrated that hangover provokes mitochondrial dysfunction, oxidative stress, imbalance in antioxidant defenses, and impairment in cellular bioenergetics. Chronic and acute ethanol intake induces neuroapoptosis but there are no studies which evaluated apoptosis at alcohol hangover. The aim of the present work was to study alcohol residual effects on intrinsic and extrinsic apoptotic signaling pathways in mice brain cortex. Male Swiss mice received i.p. injection of ethanol (3.8 g/kg) or saline. Six hours after injection, at alcohol hangover onset, mitochondria and tissue lysates were obtained from brain cortex. Results indicated that during alcohol hangover a loss of granularity of mitochondria and a strong increment in mitochondrial permeability were observed, indicating the occurrence of swelling. Alcohol-treated mice showed a significant 35% increase in Bax/Bcl-2 ratio and a 5-fold increase in the ratio level of cytochrome c between mitochondria and cytosol. Caspase 3, 8 and 9 protein expressions were 32%, 33% and 20% respectively enhanced and the activity of caspase 3 and 6 was 30% and 20% increased also due to the hangover condition. Moreover, 38% and 32% increments were found in PARP1 and p53 protein expression respectively and on the contrary, SIRT-1 was almost 50% lower than controls due to the hangover condition. The present work demonstrates that alcohol after-effects could result in the activation of mitochondrial and non-mitochondrial apoptosis pathways.
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Affiliation(s)
- Analía G Karadayian
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Fisicoquímica, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Bioquímica y Medicina Molecular Prof. Alberto Boveris (IBIMOL) Buenos Aires, Argentina
| | - Analia Czerniczyniec
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Fisicoquímica, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Bioquímica y Medicina Molecular Prof. Alberto Boveris (IBIMOL) Buenos Aires, Argentina
| | - Silvia Lores-Arnaiz
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Fisicoquímica, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Bioquímica y Medicina Molecular Prof. Alberto Boveris (IBIMOL) Buenos Aires, Argentina.
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3
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Beresewicz-Haller M. Hippocampal region-specific endogenous neuroprotection as an approach in the search for new neuroprotective strategies in ischemic stroke. Fiction or fact? Neurochem Int 2023; 162:105455. [PMID: 36410452 DOI: 10.1016/j.neuint.2022.105455] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 11/03/2022] [Accepted: 11/17/2022] [Indexed: 11/23/2022]
Abstract
Ischemic stroke is the leading cause of death and long-term disability worldwide, and, while considerable progress has been made in understanding its pathophysiology, the lack of effective treatments remains a major concern. In that context, receiving more and more consideration as a promising therapeutic method is the activation of natural adaptive mechanisms (endogenous neuroprotection) - an approach that seeks to enhance and/or stimulate the endogenous processes of plasticity and protection of the neuronal system that trigger the brain's intrinsic capacity for self-defence. Ischemic preconditioning is a classic example of endogenous neuroprotection, being the process by which one or more brief, non-damaging episodes of ischemia-reperfusion (I/R) induce tissue resistance to subsequent prolonged, damaging ischemia. Another less-known example is resistance to an I/R episode mounted by the hippocampal region consisting of CA2, CA3, CA4 and the dentate gyrus (here abbreviated to CA2-4, DG). This can be contrasted with the ischemia-vulnerable CA1 region. There is not yet a good understanding of these different sensitivities of the hippocampal regions, and hence of the endogenous neuroprotection characteristic of CA2-4, DG. However, this region is widely reported to have properties distinct from CA1, and capable of generating resistance to an I/R episode. These include activation of neurotrophic and neuroprotective factors, greater activation of anti-excitotoxic and anti-oxidant mechanisms, increased plasticity potential, a greater energy reserve and improved mitochondrial function. This review seeks to summarize properties of CA2-4, DG in the context of endogenous neuroprotection, and then to assess the potential utility of these properties to therapeutic approaches. In so doing, it appears to represent the first such addressing of the issue of ischemia resistance attributable to CA2-4, DG.
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Is Nrf2 Behind Endogenous Neuroprotection of the Hippocampal CA2-4,DG Region? Mol Neurobiol 2023; 60:1645-1658. [PMID: 36547847 PMCID: PMC9899192 DOI: 10.1007/s12035-022-03166-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 12/10/2022] [Indexed: 12/24/2022]
Abstract
The transcription factor nuclear factor-erythroid 2-related factor 2 (Nrf2) is the master regulator of genes known to be involved in antioxidant, and anti-inflammatory processes, metabolic regulation, and other cellular functions. Here, we also hypothesize a core role for it in endogenous neuroprotection, i.e., the natural adaptive mechanisms protecting the brain from ischemia-reperfusion (I/R) episode. An example of endogenous neuroprotection is ischemia-resistance of the hippocampal regions comprising the CA2, CA3, CA4 and dentate gyrus subfields (here abbreviated to CA2-4,DG) which can be contrasted with the ischemia-vulnerable CA1 region. In the work detailed here, we used a gerbil model of transient cerebral ischemia to examined Nrf2 activation in CA1 and CA2-4,DG, in a control group, and post I/R episode. Data obtained indicate enhanced Nrf2 activity in CA2-4,DG as compared with CA1 in the control, with this difference seen to persist even after I/R. While I/R does indeed cause further activation of Nrf2 in CA2-4,DG, it is associated with slight and transient activation in CA1. Sub-regional differences in Nrf2 activity correlate with immunoreactivity of Keap1 (an Nrf2 suppressor) and Nrf2 target proteins, including heme oxygenase 1, the catalytic and modulatory sub-units of glutamate-cysteine ligase, and glutathione peroxidase 1. Pharmacological Nrf2 activation by sulforaphane results in protection of CA1 after I/R episode. Our results therefore suggest that high Nrf2 activity in CA2-4,DG may guarantee resistance of this region to I/R, potentially explaining the differential sensitivities of the hippocampal regions.
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Patalas-Krawczyk P, Malinska D, Walczak J, Kratzer G, Prill M, Michalska B, Drabik K, Titz B, Eb-Levadoux Y, Schneider T, Szymanski J, Hoeng J, Peitsch MC, Duszynski J, Szczepanowska J, Van der Toorn M, Mathis C, Wieckowski MR. Effects of plant alkaloids on mitochondrial bioenergetic parameters. Food Chem Toxicol 2021; 154:112316. [PMID: 34089800 DOI: 10.1016/j.fct.2021.112316] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 05/26/2021] [Accepted: 05/29/2021] [Indexed: 10/21/2022]
Abstract
Mitochondria are among the first responders to various stress factors that challenge cell and tissue homeostasis. Various plant alkaloids have been investigated for their capacity to modulate mitochondrial activities. In this study, we used isolated mitochondria from mouse brain and liver tissues to assess nicotine, anatabine and anabasine, three alkaloids found in tobacco plant, for potential modulatory activity on mitochondrial bioenergetics parameters. All alkaloids decreased basal oxygen consumption of mouse brain mitochondria in a dose-dependent manner without any effect on the ADP-stimulated respiration. None of the alkaloids, at 1 nM or 1.25 μM concentrations, influenced the maximal rate of swelling of brain mitochondria. In contrast to brain mitochondria, 1.25 μM anatabine, anabasine and nicotine increased maximal rate of swelling of liver mitochondria suggesting a toxic effect. Only at 1 mM concentration, anatabine slowed down the maximal rate of Ca2+-induced swelling and increased the time needed to reach the maximal rate of swelling. The observed mitochondrial bioenergetic effects are probably mediated through a pathway independent of nicotinic acetylcholine receptors, as quantitative proteomic analysis could not confirm their expression in pure mitochondrial fractions isolated from mouse brain tissue.
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Affiliation(s)
| | - Dominika Malinska
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
| | - Jaroslaw Walczak
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
| | - Gilles Kratzer
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000, Neuchâtel, Switzerland.
| | - Monika Prill
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
| | - Bernadeta Michalska
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
| | - Karolina Drabik
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
| | - Bjorn Titz
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000, Neuchâtel, Switzerland.
| | - Yvan Eb-Levadoux
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000, Neuchâtel, Switzerland.
| | | | - Jedrzej Szymanski
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
| | - Julia Hoeng
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000, Neuchâtel, Switzerland.
| | - Manuel C Peitsch
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000, Neuchâtel, Switzerland.
| | - Jerzy Duszynski
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
| | - Joanna Szczepanowska
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
| | - Marco Van der Toorn
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000, Neuchâtel, Switzerland.
| | - Carole Mathis
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000, Neuchâtel, Switzerland.
| | - Mariusz R Wieckowski
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
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Ramírez-Pérez G, Sánchez-Chávez G, Salceda R. Mitochondrial bound hexokinase type I in normal and streptozotocin diabetic rat retina. Mitochondrion 2020; 52:212-217. [DOI: 10.1016/j.mito.2020.04.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 02/24/2020] [Accepted: 04/07/2020] [Indexed: 12/19/2022]
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7
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Addressing the alterations in cerebral ischemia-reperfusion injury on the brain mitochondrial activity: A possible link to cognitive decline. Biochem Biophys Res Commun 2019; 518:100-106. [DOI: 10.1016/j.bbrc.2019.08.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Accepted: 08/05/2019] [Indexed: 11/18/2022]
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8
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Ravindran S, Kurian GA. Eventual analysis of global cerebral ischemia-reperfusion injury in rat brain: a paradigm of a shift in stress and its influence on cognitive functions. Cell Stress Chaperones 2019; 24:581-594. [PMID: 31025239 PMCID: PMC6527675 DOI: 10.1007/s12192-019-00990-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 03/18/2019] [Accepted: 03/24/2019] [Indexed: 12/31/2022] Open
Abstract
Cognitive issues in stroke arise as a result of reperfusion of a clogged artery, which is reported to exacerbate the injury in the brain leading to oxidative stress. Through the present work, we try to understand the regional variations across brain regions mainly cortex and striatum associated with the progression of ischemia-reperfusion injury (IRI). In a rat model of IRI, the influence of varying ischemia and reperfusion times on the biochemical phases across the brain regions were monitored. IRI resulted in the blood-brain barrier disruption and developed mild areas of risk. The brain's tolerance towards IRI indicated a progressive trend in the injury and apoptosis from ischemia to reperfusion that was supported by the activities of plasma lactate dehydrogenase and tissue caspase-3. Cognitive impairment in these rats was an implication of cellular oxidative stress (higher lipid peroxidation and lower antioxidant enzyme activity) that persisted by 24-h reperfusion. The oxidative stress was prominent in the cortex than the striatum and was supported by the lower ATP level. Upregulated Mn-SOD expression leading to a preserved mitochondria in the striatum could be attributed to the regional protection. Overall, a progression of IRI was observed from striatum to cortex leading to 5-day cognitive decline.
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Affiliation(s)
- Sriram Ravindran
- Vascular Biology Laboratory, SASTRA Deemed University, Thanjavur, Tamil Nadu 613401 India
| | - Gino A. Kurian
- Vascular Biology Laboratory, SASTRA Deemed University, Thanjavur, Tamil Nadu 613401 India
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9
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Springer JE, Visavadiya NP, Sullivan PG, Hall ED. Post-Injury Treatment with NIM811 Promotes Recovery of Function in Adult Female Rats after Spinal Cord Contusion: A Dose-Response Study. J Neurotrauma 2017; 35:492-499. [PMID: 28967329 DOI: 10.1089/neu.2017.5167] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Mitochondrial homeostasis is essential for maintaining cellular function and survival in the central nervous system (CNS). Mitochondrial function is significantly compromised after spinal cord injury (SCI) and is associated with accumulation of high levels of calcium, increased production of free radicals, oxidative damage, and eventually mitochondrial permeability transition (mPT). The formation of the mPT pore (mPTP) and subsequent mPT state are considered to be end stage events in the decline of mitochondrial integrity, and strategies that inhibit mPT can limit mitochondrial demise. Cyclosporine A (CsA) is thought to inhibit mPT by binding to cyclophilin D and has been shown to be effective in models of CNS injury. CsA, however, also inhibits calcineurin, which is responsible for its immunosuppressive properties. In the present study, we conducted a dose-response examination of NIM811, a nonimmunosuppressive CsA analog, on recovery of function and tissue sparing in a rat model of moderate to severe SCI. The results of our experiments revealed that NIM811 (10 mg/kg) significantly improved open field locomotor performance, while the two higher doses tested (20 and 40 mg/kg) significantly improved return of reflexive bladder control and significantly decreased the rostral-caudal extent of the lesion. Taken together, these results demonstrate the ability of NIM811 to improve recovery of function in SCI and support the role of protecting mitochondrial function as a potential therapeutic target.
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Affiliation(s)
- Joe E Springer
- Department of Neuroscience, Spinal Cord and Brain Injury Research Center, University of Kentucky Medical Center , Lexington, Kentucky
| | - Nishant P Visavadiya
- Department of Neuroscience, Spinal Cord and Brain Injury Research Center, University of Kentucky Medical Center , Lexington, Kentucky
| | - Patrick G Sullivan
- Department of Neuroscience, Spinal Cord and Brain Injury Research Center, University of Kentucky Medical Center , Lexington, Kentucky
| | - Edward D Hall
- Department of Neuroscience, Spinal Cord and Brain Injury Research Center, University of Kentucky Medical Center , Lexington, Kentucky
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Graham LC, Eaton SL, Brunton PJ, Atrih A, Smith C, Lamont DJ, Gillingwater TH, Pennetta G, Skehel P, Wishart TM. Proteomic profiling of neuronal mitochondria reveals modulators of synaptic architecture. Mol Neurodegener 2017; 12:77. [PMID: 29078798 PMCID: PMC5659037 DOI: 10.1186/s13024-017-0221-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 10/19/2017] [Indexed: 02/16/2023] Open
Abstract
Background Neurons are highly polarized cells consisting of three distinct functional domains: the cell body (and associated dendrites), the axon and the synapse. Previously, it was believed that the clinical phenotypes of neurodegenerative diseases were caused by the loss of entire neurons, however it has recently become apparent that these neuronal sub-compartments can degenerate independently, with synapses being particularly vulnerable to a broad range of stimuli. Whilst the properties governing the differential degenerative mechanisms remain unknown, mitochondria consistently appear in the literature, suggesting these somewhat promiscuous organelles may play a role in affecting synaptic stability. Synaptic and non-synaptic mitochondrial subpools are known to have different enzymatic properties (first demonstrated by Lai et al., 1977). However, the molecular basis underpinning these alterations, and their effects on morphology, has not been well documented. Methods The current study has employed electron microscopy, label-free proteomics and in silico analyses to characterize the morphological and biochemical properties of discrete sub-populations of mitochondria. The physiological relevance of these findings was confirmed in-vivo using a molecular genetic approach at the Drosophila neuromuscular junction. Results Here, we demonstrate that mitochondria at the synaptic terminal are indeed morphologically different to non-synaptic mitochondria, in both rodents and human patients. Furthermore, generation of proteomic profiles reveals distinct molecular fingerprints – highlighting that the properties of complex I may represent an important specialisation of synaptic mitochondria. Evidence also suggests that at least 30% of the mitochondrial enzymatic activity differences previously reported can be accounted for by protein abundance. Finally, we demonstrate that the molecular differences between discrete mitochondrial sub-populations are capable of selectively influencing synaptic morphology in-vivo. We offer several novel mitochondrial candidates that have the propensity to significantly alter the synaptic architecture in-vivo. Conclusions Our study demonstrates discrete proteomic profiles exist dependent upon mitochondrial subcellular localization and selective alteration of intrinsic mitochondrial proteins alters synaptic morphology in-vivo. Electronic supplementary material The online version of this article (10.1186/s13024-017-0221-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Laura C Graham
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, UK.,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK
| | - Samantha L Eaton
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, UK.,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK
| | - Paula J Brunton
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, UK
| | - Abdelmadjid Atrih
- FingerPrints Proteomics Facility, College of Life Sciences, University of Dundee, Dundee, UK
| | - Colin Smith
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK.,Department of Academic Neuropathology, University of Edinburgh, CCBS, Chancellor's Building, Little France, Edinburgh, UK
| | - Douglas J Lamont
- FingerPrints Proteomics Facility, College of Life Sciences, University of Dundee, Dundee, UK
| | - Thomas H Gillingwater
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK.,Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, Edinburgh, UK
| | - Giuseppa Pennetta
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK.,Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, Edinburgh, UK
| | - Paul Skehel
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK.,Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, Edinburgh, UK
| | - Thomas M Wishart
- Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, UK. .,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK.
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Grings M, Moura AP, Parmeggiani B, Motta MM, Boldrini RM, August PM, Matté C, Wyse ATS, Wajner M, Leipnitz G. Higher susceptibility of cerebral cortex and striatum to sulfite neurotoxicity in sulfite oxidase-deficient rats. Biochim Biophys Acta Mol Basis Dis 2016; 1862:2063-2074. [PMID: 27523630 DOI: 10.1016/j.bbadis.2016.08.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Revised: 07/27/2016] [Accepted: 08/09/2016] [Indexed: 12/22/2022]
Abstract
Patients affected by sulfite oxidase (SO) deficiency present severe seizures early in infancy and progressive neurological damage, as well as tissue accumulation of sulfite, thiosulfate and S-sulfocysteine. Since the pathomechanisms involved in the neuropathology of SO deficiency are still poorly established, we evaluated the effects of sulfite on redox homeostasis and bioenergetics in cerebral cortex, striatum, cerebellum and hippocampus of rats with chemically induced SO deficiency. The deficiency was induced in 21-day-old rats by adding 200ppm of tungsten, a molybdenum competitor, in their drinking water for 9weeks. Sulfite (70mg/kg/day) was also administered through the drinking water from the third week of tungsten supplementation until the end of the treatment. Sulfite decreased reduced glutathione concentrations and the activities of glutathione reductase and glutathione S-transferase (GST) in cerebral cortex and of GST in cerebellum of SO-deficient rats. Moreover, sulfite increased the activities of complexes II and II-III in striatum and of complex II in hippocampus, but reduced the activity of complex IV in striatum of SO-deficient rats. Sulfite also decreased the mitochondrial membrane potential in cerebral cortex and striatum, whereas it had no effect on mitochondrial mass in any encephalic tissue evaluated. Finally, sulfite inhibited the activities of malate and glutamate dehydrogenase in cerebral cortex of SO-deficient rats. Taken together, our findings indicate that cerebral cortex and striatum are more vulnerable to sulfite-induced toxicity than cerebellum and hippocampus. It is presumed that these pathomechanisms may contribute to the pathophysiology of neurological damage found in patients affected by SO deficiency.
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Affiliation(s)
- Mateus Grings
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Alana Pimentel Moura
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Belisa Parmeggiani
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Marcela Moreira Motta
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Rafael Mello Boldrini
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Pauline Maciel August
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Cristiane Matté
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003, Porto Alegre, RS, Brazil
| | - Angela T S Wyse
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003, Porto Alegre, RS, Brazil
| | - Moacir Wajner
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003, Porto Alegre, RS, Brazil; Serviço de Genética Médica, Hospital de Clínicas de Porto Alegre, Rua Ramiro Barcelos, 2350, CEP 90035-903, Porto Alegre, RS, Brazil
| | - Guilhian Leipnitz
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003, Porto Alegre, RS, Brazil.
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Schmidt-Kastner R. Genomic approach to selective vulnerability of the hippocampus in brain ischemia–hypoxia. Neuroscience 2015; 309:259-79. [DOI: 10.1016/j.neuroscience.2015.08.034] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Revised: 08/12/2015] [Accepted: 08/17/2015] [Indexed: 01/06/2023]
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13
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Alcohol hangover induces mitochondrial dysfunction and free radical production in mouse cerebellum. Neuroscience 2015; 304:47-59. [PMID: 26192095 DOI: 10.1016/j.neuroscience.2015.07.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 07/02/2015] [Accepted: 07/02/2015] [Indexed: 11/23/2022]
Abstract
Alcohol hangover (AH) is defined as the temporary state after alcohol binge-like drinking, starting when ethanol (EtOH) is absent in plasma. Previous data indicate that AH induces mitochondrial dysfunction and free radical production in mouse brain cortex. The aim of this work was to study mitochondrial function and reactive oxygen species production in mouse cerebellum at the onset of AH. Male mice received a single i.p. injection of EtOH (3.8g/kg BW) or saline solution. Mitochondrial function was evaluated 6h after injection (AH onset). At the onset of AH, malate-glutamate and succinate-supported state 4 oxygen uptake was 2.3 and 1.9-fold increased leading to a reduction in respiratory control of 55% and 48% respectively, as compared with controls. Decreases of 38% and 16% were found in Complex I-III and IV activities. Complex II-III activity was not affected by AH. Mitochondrial membrane potential and mitochondrial permeability changes were evaluated by flow cytometry. Mitochondrial membrane potential and permeability were decreased by AH in cerebellum mitochondria. Together with this, AH induced a 25% increase in superoxide anion and a 92% increase in hydrogen peroxide production in cerebellum mitochondria. Related to nitric oxide (NO) metabolism, neuronal nitric oxide synthase (nNOS) protein expression was 52% decreased by the hangover condition compared with control group. No differences were found in cerebellum NO production between control and treated mice. The present work demonstrates that the physiopathological state of AH involves mitochondrial dysfunction in mouse cerebellum showing the long-lasting effects of acute EtOH exposure in the central nervous system.
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Yu N, Wang S, Wang P, Li Y, Li S, Wang L, Chen H, Wang Y. The calcium uniporter regulates the permeability transition pore in isolated cortical mitochondria. Neural Regen Res 2015; 7:109-13. [PMID: 25767484 PMCID: PMC4354124 DOI: 10.3969/j.issn.1673-5374.2012.02.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Accepted: 12/20/2011] [Indexed: 01/28/2023] Open
Abstract
To investigate the influence of the mitochondrial calcium uniporter on the mitochondrial permeability transition pore, the present study observed mitochondrial morphology in cortical neurons isolated from adult rats using transmission electron microscopy, and confirmed the morphology and activity of isolated mitochondria by detecting succinic dehydrogenase and monoamine oxidase, two mitochondrial enzymes. Isolated mitochondria were treated with either ruthenium red, an inhibitor of the uniporter, spermine, an activator of the uniporter, or in combination with cyclosporin A, an inhibitor of the mitochondrial permeability transition pore. Results showed that ruthenium red inhibited CaCl2-induced mitochondrial permeability transition pore opening, spermine enhanced opening, and cyclosporin A attenuated the effects of spermine. Results demonstrated that the mitochondrial calcium uniporter plays a role in regulating the mitochondrial permeability transition pore in mitochondria isolated from the rat brain cortex.
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Affiliation(s)
- Ning Yu
- Department of Anesthesiology, Affiliated Hospital of Qingdao University Medical College, Qingdao 266003, Shandong Province, China
| | - Shilei Wang
- Department of Anesthesiology, Affiliated Hospital of Qingdao University Medical College, Qingdao 266003, Shandong Province, China
| | - Peng Wang
- Department of Anesthesiology, Affiliated Hospital of Qingdao University Medical College, Qingdao 266003, Shandong Province, China
| | - Yu Li
- Department of Anesthesiology, Affiliated Hospital of Qingdao University Medical College, Qingdao 266003, Shandong Province, China
| | - Shuhong Li
- Department of Anesthesiology, Affiliated Hospital of Qingdao University Medical College, Qingdao 266003, Shandong Province, China
| | - Li Wang
- Department of Anesthesiology, Affiliated Hospital of Qingdao University Medical College, Qingdao 266003, Shandong Province, China
| | - Hongbing Chen
- Cerebrovascular Disease Institute, Qingdao University Medical College, Qingdao 266003, Shandong Province, China
| | - Yanting Wang
- Department of Anesthesiology, Affiliated Hospital of Qingdao University Medical College, Qingdao 266003, Shandong Province, China
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15
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Steiner JP, Bachani M, Wolfson-Stofko B, Lee MH, Wang T, Li G, Li W, Strayer D, Haughey NJ, Nath A. Interaction of paroxetine with mitochondrial proteins mediates neuroprotection. Neurotherapeutics 2015; 12:200-16. [PMID: 25404050 PMCID: PMC4322069 DOI: 10.1007/s13311-014-0315-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
There are severe neurological complications that arise from HIV infection, ranging from peripheral sensory neuropathy to cognitive decline and dementia for which no specific treatments are available. The HIV proteins secreted from infected macrophages, gp120 and Tat, are neurotoxic. The goal of this study was to screen, identify and develop neuroprotective compounds relevant to HIV-associated neurocognitive disorders (HAND). We screened more than 2000 compounds that included FDA approved drugs for protective efficacy against oxidative stress-mediated neurodegeneration and identified selective serotonin reuptake inhibitors (SSRIs) as potential neuroprotectants. Numerous SSRIs were then extensively evaluated as protectants against neurotoxicity as measured by changes in neuronal cell death, mitochondrial potential, and axodendritic degeneration elicited by HIV Tat and gp120 and other mitochondrial toxins. While many SSRIs demonstrated neuroprotective actions, paroxetine was potently neuroprotective (100 nM potency) against these toxins in vitro and in vivo following systemic administration in a gp120 neurotoxicity model. Interestingly, the inhibition of serotonin reuptake by paroxetine was not required for neuroprotection, since depletion of the serotonin transporter had no effect on its neuroprotective properties. We determined that paroxetine interacts selectively and preferentially with brain mitochondrial proteins and blocks calcium-dependent swelling but had less effect on liver mitochondria. Additionally, paroxetine induced proliferation of neural progenitor cells in vitro and in vivo in gp120 transgenic animals. Therefore, SSRIs such as paroxetine may provide a novel adjunctive neuroprotective and neuroregenerative therapy to treat HIV-infected individuals.
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Affiliation(s)
- Joseph P. Steiner
- />Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287 USA
- />Translational Neuroscience Center, National Institute of Neurological Diseases and Stroke, National Bldg 10, Room 7C-105, 10 Center Drive, Bethesda, MD 20892 USA
| | - Muznabanu Bachani
- />Translational Neuroscience Center, National Institute of Neurological Diseases and Stroke, National Bldg 10, Room 7C-105, 10 Center Drive, Bethesda, MD 20892 USA
| | - Brett Wolfson-Stofko
- />Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287 USA
| | - Myoung-Hwa Lee
- />Section of Infections of the Nervous System, National Institute of Neurological Diseases and Stroke, National Institute of Health, Bldg 10, Room 7C103, 10 Center Drive, Bethesda, MD 20892 USA
| | - Tonguang Wang
- />Translational Neuroscience Center, National Institute of Neurological Diseases and Stroke, National Bldg 10, Room 7C-105, 10 Center Drive, Bethesda, MD 20892 USA
| | - Guanhan Li
- />Section of Infections of the Nervous System, National Institute of Neurological Diseases and Stroke, National Institute of Health, Bldg 10, Room 7C103, 10 Center Drive, Bethesda, MD 20892 USA
| | - Wenxue Li
- />Section of Infections of the Nervous System, National Institute of Neurological Diseases and Stroke, National Institute of Health, Bldg 10, Room 7C103, 10 Center Drive, Bethesda, MD 20892 USA
| | - David Strayer
- />Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107 USA
| | - Norman J. Haughey
- />Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287 USA
| | - Avindra Nath
- />Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287 USA
- />Translational Neuroscience Center, National Institute of Neurological Diseases and Stroke, National Bldg 10, Room 7C-105, 10 Center Drive, Bethesda, MD 20892 USA
- />Section of Infections of the Nervous System, National Institute of Neurological Diseases and Stroke, National Institute of Health, Bldg 10, Room 7C103, 10 Center Drive, Bethesda, MD 20892 USA
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16
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Galli GLJ, Richards JG. Mitochondria from anoxia-tolerant animals reveal common strategies to survive without oxygen. J Comp Physiol B 2014; 184:285-302. [DOI: 10.1007/s00360-014-0806-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Revised: 01/09/2014] [Accepted: 01/17/2014] [Indexed: 12/15/2022]
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17
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Brophy GM, Mazzeo AT, Brar S, Alves OL, Bunnell K, Gilman C, Karnes T, Hayes RL, Bullock R. Exposure of cyclosporin A in whole blood, cerebral spinal fluid, and brain extracellular fluid dialysate in adults with traumatic brain injury. J Neurotrauma 2013; 30:1484-9. [PMID: 23540442 DOI: 10.1089/neu.2012.2524] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Cyclosporin A (CsA), an immunosuppressive medication traditionally used in the prevention of post-transplant rejection, is a promising neuroprotective agent for traumatic brain injury (TBI). Preliminary studies in animals and humans describe the efficacy and safety of CsA when administered following neurotrauma. The objective of this study is to describe CsA exposure in adults with severe TBI by assessing concentrations in whole blood, cerebrospinal fluid (CSF), and brain extracellular fluid (ECF) dialysate as measured by brain microdialysis. Severe TBI patients were enrolled in a randomized controlled trial following the written informed consent of their legal guardians. Patients received either CsA 5 mg/kg as a continuous infusion over 24 h, or matching placebo. Noncompartmental exposure analyses were performed using CsA concentrations in whole blood, CSF, and ECF dialysate. There were 37 patients randomized to the CsA arm of the trial and included in this exposure analysis. CsA was detected in the ECF dialysate and CSF at a fraction of the whole blood concentration. Mean CsA maximum concentrations were achieved at 24 and 30 h from the start of the 24 h infusion, in the CSF and ECF dialysate, respectively. A correlation was found between ECF dialysate and CSF concentrations. CsA was detected in the blood, CSF, and brain ECF dialysate. CsA exposure characteristic differences exist for whole blood, CSF, and ECF dialysate in severe TBI patients when administered as a continuous intravenous infusion. These exposure characteristics should be used for safer CsA dose optimization to achieve target CsA concentrations for neuroprotection in future TBI studies.
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Affiliation(s)
- Gretchen M Brophy
- Department of Pharmacotherapy and Outcomes Science, Medical College of Virginia Campus, Richmond, Virginia 23298-0533, USA.
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18
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Morota S, Manolopoulos T, Eyjolfsson A, Kimblad PO, Wierup P, Metzsch C, Blomquist S, Hansson MJ. Functional and pharmacological characteristics of permeability transition in isolated human heart mitochondria. PLoS One 2013; 8:e67747. [PMID: 23840770 PMCID: PMC3695980 DOI: 10.1371/journal.pone.0067747] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 05/22/2013] [Indexed: 11/18/2022] Open
Abstract
The objective of the present study was to validate the presence and explore the characteristics of mitochondrial permeability transition (mPT) in isolated mitochondria from human heart tissue in order to investigate if previous findings in animal models of cardiac disorders are translatable to human disease. Mitochondria were rapidly isolated from fresh atrial tissue samples obtained from 14 patients undergoing Maze surgery due to atrial fibrillation. Human heart mitochondria exhibited typical mPT characteristics upon calcium overload such as swelling, evaluated by changes in light scattering, inhibition of respiration and loss of respiratory coupling. Swelling was a morphologically reversible event following transient calcium challenge. Calcium retention capacity (CRC), a quantitative measure of mPT sensitivity assayed by following extramitochondrial [Ca(2+)] and changes in respiration during a continuous calcium infusion, was significantly increased by cyclophilin D (CypD) inhibitors. The thiol-reactive oxidant phenylarsine oxide sensitized mitochondria to calcium-induced mPT. Release of the pro-apoptotic intermembrane protein cytochrome c was increased after, but not before, calcium discharge and respiratory inhibition in the CRC assay. From the present study, we conclude that adult viable heart mitochondria have a CypD- and oxidant-regulated mPT. The findings support that inhibition of mPT may be a relevant pharmacological target in human cardiac disease and may underlie the beneficial effect of cyclosporin A in reperfusion injury.
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Affiliation(s)
- Saori Morota
- Mitochondrial Pathophysiology Unit, Skåne University Hospital & Lund University, Lund, Sweden
| | - Theodor Manolopoulos
- Department of Cardiothoracic Anesthesiology and Intensive Care, Skåne University Hospital & Lund University, Lund, Sweden
| | - Atli Eyjolfsson
- Department of Cardiothoracic Surgery, Skåne University Hospital & Lund University, Lund, Sweden
| | - Per-Ola Kimblad
- Department of Cardiothoracic Surgery, Skåne University Hospital & Lund University, Lund, Sweden
| | - Per Wierup
- Department of Cardiothoracic Surgery, Skåne University Hospital & Lund University, Lund, Sweden
| | - Carsten Metzsch
- Department of Cardiothoracic Anesthesiology and Intensive Care, Skåne University Hospital & Lund University, Lund, Sweden
| | - Sten Blomquist
- Department of Cardiothoracic Anesthesiology and Intensive Care, Skåne University Hospital & Lund University, Lund, Sweden
| | - Magnus J. Hansson
- Mitochondrial Pathophysiology Unit, Skåne University Hospital & Lund University, Lund, Sweden
- Department of Clinical Physiology, Skåne University Hospital & Lund University, Lund, Sweden
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19
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Gillingwater TH, Wishart TM. Mechanisms underlying synaptic vulnerability and degeneration in neurodegenerative disease. Neuropathol Appl Neurobiol 2013; 39:320-34. [PMID: 23289367 DOI: 10.1111/nan.12014] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Accepted: 12/21/2012] [Indexed: 02/06/2023]
Abstract
Recent developments in our understanding of events underlying neurodegeneration across the central and peripheral nervous systems have highlighted the critical role that synapses play in the initiation and progression of neuronal loss. With the development of increasingly accurate and versatile animal models of neurodegenerative disease it has become apparent that disruption of synaptic form and function occurs comparatively early, preceding the onset of degenerative changes in the neuronal cell body. Yet, despite our increasing awareness of the importance of synapses in neurodegeneration, the mechanisms governing the particular susceptibility of distal neuronal processes are only now becoming clear. In this review we bring together recent developments in our understanding of cellular and molecular mechanisms regulating synaptic vulnerability. We have placed a particular focus on three major areas of research that have gained significant interest over the last few years: (i) the contribution of synaptic mitochondria to neurodegeneration; (ii) the contribution of pathways that modulate synaptic function; and (iii) regulation of synaptic degeneration by local posttranslational modifications such as ubiquitination. We suggest that targeting these organelles and pathways may be a productive way to develop synaptoprotective strategies applicable to a range of neurodegenerative conditions.
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Affiliation(s)
- T H Gillingwater
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
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20
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Meratan AA, Nemat-Gorgani M. Mitochondrial membrane permeabilization upon interaction with lysozyme fibrillation products: Role of mitochondrial heterogeneity. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2012; 1818:2149-57. [DOI: 10.1016/j.bbamem.2012.04.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Revised: 04/18/2012] [Accepted: 04/26/2012] [Indexed: 11/30/2022]
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21
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Physiological uncoupling of mitochondrial oxidative phosphorylation. Studies in different yeast species. J Bioenerg Biomembr 2011; 43:323-31. [PMID: 21556887 DOI: 10.1007/s10863-011-9356-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Under non-phosphorylating conditions a high proton transmembrane gradient inhibits the rate of oxygen consumption mediated by the mitochondrial respiratory chain (state IV). Slow electron transit leads to production of reactive oxygen species (ROS) capable of participating in deleterious side reactions. In order to avoid overproducing ROS, mitochondria maintain a high rate of O(2) consumption by activating different exquisitely controlled uncoupling pathways. Different yeast species possess one or more uncoupling systems that work through one of two possible mechanisms: i) Proton sinks and ii) Non-pumping redox enzymes. Proton sinks are exemplified by mitochondrial unspecific channels (MUC) and by uncoupling proteins (UCP). Saccharomyces. cerevisiae and Debaryomyces hansenii express highly regulated MUCs. Also, a UCP was described in Yarrowia lipolytica which promotes uncoupled O(2) consumption. Non-pumping alternative oxido-reductases may substitute for a pump, as in S. cerevisiae or may coexist with a complete set of pumps as in the branched respiratory chains from Y. lipolytica or D. hansenii. In addition, pumps may suffer intrinsic uncoupling (slipping). Promising models for study are unicellular parasites which can turn off their aerobic metabolism completely. The variety of energy dissipating systems in eukaryote species is probably designed to control ROS production in the different environments where each species lives.
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22
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Vaz AR, Silva SL, Barateiro A, Falcão AS, Fernandes A, Brito MA, Brites D. Selective vulnerability of rat brain regions to unconjugated bilirubin. Mol Cell Neurosci 2011; 48:82-93. [PMID: 21708263 DOI: 10.1016/j.mcn.2011.06.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2010] [Revised: 06/06/2011] [Accepted: 06/10/2011] [Indexed: 12/22/2022] Open
Abstract
Hippocampus is one of the brain regions most vulnerable to unconjugated bilirubin (UCB) encephalopathy, although cerebellum also shows selective yellow staining in kernicterus. We previously demonstrated that UCB induces oxidative stress in cortical neurons, disruption of neuronal network dynamics, either in developing cortical or hippocampal neurons, and that immature cortical neurons are more prone to UCB-induced injury. Here, we studied if immature rat neurons isolated from cortex, cerebellum and hippocampus present distinct features of oxidative stress and cell dysfunction upon UCB exposure. We also explored whether oxidative damage and its regulation contribute to neuronal dysfunction induced by hyperbilirubinemia, considering neurite extension and ramification, as well as cell death. Our results show that UCB induces nitric oxide synthase expression, as well as production of nitrites and cyclic guanosine monophosphate in immature neurons, mainly in those from hippocampus. After exposure to UCB, hippocampal neurons presented the highest content of reactive oxygen species, disruption of glutathione redox status and cell death, when compared to neurons from cortex or cerebellum. In particular, the results indicate that cells exposed to UCB undertake an adaptive response that involves DJ-1, a multifunctional neuroprotective protein implicated in the maintenance of cellular oxidation status. However, longer neuronal exposure to UCB caused down-regulation of DJ-1 expression, especially in hippocampal neurons. In addition, a greater impairment in neurite outgrowth and branching following UCB treatment was also noticed in immature neurons from hippocampus. Interestingly, pre-incubation with N-acetylcysteine, a precursor of glutathione synthesis, protected neurons from UCB-induced oxidative stress and necrotic cell death, preventing DJ-1 down-regulation and neuritic impairment. Taken together, these data point to oxidative injury and disruption of neuritic network as hallmarks in hippocampal susceptibility to UCB. Most importantly, they also suggest that local differences in glutathione content may account to the different susceptibility between brain regions exposed to UCB.
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Affiliation(s)
- Ana Rita Vaz
- Research Institute for Medicines and Pharmaceutical Sciences, Faculty of Pharmacy, University of Lisbon, Lisbon, Portugal
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23
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Gizatullina ZZ, Gaynutdinov TM, Svoboda H, Jerzembek D, Knabe A, Vielhaber S, Malesevic M, Heinze HJ, Fischer G, Striggow F, Gellerich FN. Effects of cyclosporine A and its immunosuppressive or non-immunosuppressive derivatives [D-Ser]8-CsA and Cs9 on mitochondria from different brain regions. Mitochondrion 2011; 11:421-9. [DOI: 10.1016/j.mito.2010.12.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Revised: 11/16/2010] [Accepted: 12/08/2010] [Indexed: 11/17/2022]
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24
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Mitochondrial Unselective Channels throughout the eukaryotic domain. Mitochondrion 2011; 11:382-90. [DOI: 10.1016/j.mito.2011.02.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 02/16/2011] [Accepted: 02/25/2011] [Indexed: 02/03/2023]
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25
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Chen L, Bai S, Su W, Song X, Zhang P, Li L, Ji JJ. Transient oxygen-glucose deprivation causes immediate changes in redox activity in mouse brain tissue. Brain Res 2011; 1390:99-107. [PMID: 21414304 DOI: 10.1016/j.brainres.2011.03.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Revised: 03/08/2011] [Accepted: 03/09/2011] [Indexed: 12/22/2022]
Abstract
Redox activity is an important property of living cells, and decreases in redox activity are likely to be an upstream event in ischemic brain injuries. In this study, immediate changes in redox activity caused by ischemic injury were investigated in oxygen-glucose deprivation (OGD) treated mouse brain tissue. Adult mouse brain slices were subjected to 10 min or 15 min OGD treatments and were immediately stained with an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) staining procedure. After 10 min OGD, the redox activity decreased in the lateral globus pallidus (LGP), medial globus pallidus (MGP), pyramidal cell layer of hippocampus CA1 (CA1(PL)) and the granular layer of the cerebellum (cereb(GL)). After 15 min OGD, decreases also occurred in the substantia nigra (SN) and several other areas of the brain stem. Hoechst 33342 was used to confirm that changes in redox activity occurred before morphological alterations in the cellular nuclei--morphological changes were not observed even after a 60 min OGD. The results presented here indicate that functional ischemic vulnerability exists in several brain regions, and will be helpful for systematic research on mammalian brain injury caused by transient metabolic stress.
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Affiliation(s)
- Lianwan Chen
- State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing, 100101, China
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26
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Panov AV, Kubalik N, Zinchenko N, Ridings DM, Radoff DA, Hemendinger R, Brooks BR, Bonkovsky HL. Metabolic and functional differences between brain and spinal cord mitochondria underlie different predisposition to pathology. Am J Physiol Regul Integr Comp Physiol 2011; 300:R844-54. [PMID: 21248309 DOI: 10.1152/ajpregu.00528.2010] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Mitochondrial dysfunctions contribute to neurodegeneration, the locations of which vary among neurodegenerative diseases. To begin to understand what mechanisms may underlie higher vulnerability of the spinal cord motor neurons in amyotrophic lateral sclerosis, compared with brain mitochondria, we studied three major functions of rat brain mitochondria (BM) and spinal cord mitochondria (SCM) mitochondria: oxidative phosphorylation, Ca(2+) sequestration, and production of reactive oxygen species (ROS), using a new metabolic paradigm (Panov et al., J. Biol. Chem. 284: 14448-14456, 2009). We present data that SCM share some unique metabolic properties of the BM. However, SCM also have several distinctions from the BM: 1) With the exception of succinate, SCM show significantly lower rates of respiration with all substrates studied; 2) immunoblotting analysis showed that this may be due to 30-40% lower contents of respiratory enzymes and porin; 3) compared with BM, SCM sequestered 40-50% less Ca(2+), and the total tissue calcium content was 8 times higher in the spinal cord; 4) normalization for mitochondria from 1 g of tissue showed that BM can sequester several times more Ca(2+) than was available in the brain tissue, whereas SCM had the capacity to sequester only 10-20% of the total tissue Ca(2+); and 5) with succinate and succinate-containing substrate mixtures, SCM showed significantly higher state 4 respiration than BM and generated more ROS associated with the reverse electron transport. We conclude that SCM have an intrinsically higher risk of oxidative damage and overload with calcium than BM, and thus spinal cord may be more vulnerable under some pathologic conditions. (250).
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Affiliation(s)
- Alexander V Panov
- Carolinas Neuromuscular/Amyotrophic Lateral Sclerosis Center, Carolinas Medical Center, 1000 Blythe Blvd., Charlotte, North Carolina 28203, USA.
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27
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Abstract
This unit contains a protocol describing the isolation of brain mitochondria by using discontinuous Percoll gradient centrifugation. The Percoll density gradient centrifugation separates synaptosomes, myelin, and free nonsynaptic mitochondria released from cells during tissue homogenization into individual fractions. Mitochondria entrapped in synaptosomes (synaptic mitochondria) can be liberated using nitrogen cavitation and then further purified by Percoll gradient centrifugation. These methods yield mitochondria that exhibit good respiratory coupling and high respiratory rates.
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Affiliation(s)
- Tibor Kristian
- Department of Anesthesiology, Organized Research Center, School of Medicine, University of Maryland, Baltimore, Maryland, USA
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28
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A pore way to die: the role of mitochondria in reperfusion injury and cardioprotection. Biochem Soc Trans 2010; 38:841-60. [DOI: 10.1042/bst0380841] [Citation(s) in RCA: 238] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
In addition to their normal physiological role in ATP production and metabolism, mitochondria exhibit a dark side mediated by the opening of a non-specific pore in the inner mitochondrial membrane. This mitochondrial permeability transition pore (MPTP) causes the mitochondria to breakdown rather than synthesize ATP and, if unrestrained, leads to necrotic cell death. The MPTP is opened in response to Ca2+ overload, especially when accompanied by oxidative stress, elevated phosphate concentration and adenine nucleotide depletion. These conditions are experienced by the heart and brain subjected to reperfusion after a period of ischaemia as may occur during treatment of a myocardial infarction or stroke and during heart surgery. In the present article, I review the properties, regulation and molecular composition of the MPTP. The evidence for the roles of CyP-D (cyclophilin D), the adenine nucleotide translocase and the phosphate carrier are summarized and other potential interactions with outer mitochondrial membrane proteins are discussed. I then review the evidence that MPTP opening mediates cardiac reperfusion injury and that MPTP inhibition is cardioprotective. Inhibition may involve direct pharmacological targeting of the MPTP, such as with cyclosporin A that binds to CyP-D, or indirect inhibition of MPTP opening such as with preconditioning protocols. These invoke complex signalling pathways to reduce oxidative stress and Ca2+ load. MPTP inhibition also protects against congestive heart failure in hypertensive animal models. Thus the MPTP is a very promising pharmacological target for clinical practice, especially once more specific drugs are developed.
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29
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Wang X, Michaelis EK. Selective neuronal vulnerability to oxidative stress in the brain. Front Aging Neurosci 2010; 2:12. [PMID: 20552050 PMCID: PMC2874397 DOI: 10.3389/fnagi.2010.00012] [Citation(s) in RCA: 422] [Impact Index Per Article: 30.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Accepted: 03/11/2010] [Indexed: 12/21/2022] Open
Abstract
Oxidative stress (OS), caused by the imbalance between the generation and detoxification of reactive oxygen and nitrogen species (ROS/RNS), plays an important role in brain aging, neurodegenerative diseases, and other related adverse conditions, such as ischemia. While ROS/RNS serve as signaling molecules at physiological levels, an excessive amount of these molecules leads to oxidative modification and, therefore, dysfunction of proteins, nucleic acids, and lipids. The response of neurons to this pervasive stress, however, is not uniform in the brain. While many brain neurons can cope with a rise in OS, there are select populations of neurons in the brain that are vulnerable. Because of their selective vulnerability, these neurons are usually the first to exhibit functional decline and cell death during normal aging, or in age-associated neurodegenerative diseases, such as Alzheimer's disease. Understanding the molecular and cellular mechanisms of selective neuronal vulnerability (SNV) to OS is important in the development of future intervention approaches to protect such vulnerable neurons from the stresses of the aging process and the pathological states that lead to neurodegeneration. In this review, the currently known molecular and cellular factors that contribute to SNV to OS are summarized. Included among the major underlying factors are high intrinsic OS, high demand for ROS/RNS-based signaling, low ATP production, mitochondrial dysfunction, and high inflammatory response in vulnerable neurons. The contribution to the selective vulnerability of neurons to OS by other intrinsic or extrinsic factors, such as deficient DNA damage repair, low calcium-buffering capacity, and glutamate excitotoxicity, are also discussed.
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Affiliation(s)
- Xinkun Wang
- Higuchi Biosciences Center, The University of Kansas Lawrence, KS, USA
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Presynaptic mitochondria in functionally different motor neurons exhibit similar affinities for Ca2+ but exert little influence as Ca2+ buffers at nerve firing rates in situ. J Neurosci 2010; 30:1869-81. [PMID: 20130196 DOI: 10.1523/jneurosci.4701-09.2010] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Mitochondria accumulate within nerve terminals and support synaptic function, most notably through ATP production. They can also sequester Ca(2+) during nerve stimulation, but it is unknown whether this limits presynaptic Ca(2+) levels at physiological nerve firing rates. Similarly, it is unclear whether mitochondrial Ca(2+) sequestration differs between functionally different nerve terminals. We addressed these questions using a combination of synthetic and genetically encoded Ca(2+) indicators to examine cytosolic and mitochondrial Ca(2+) levels in presynaptic terminals of tonic (MN13-Ib) and phasic (MNSNb/d-Is) motor neurons in Drosophila, which, as we determined, fire during fictive locomotion at approximately 42 Hz and approximately 8 Hz, respectively. Mitochondrial Ca(2+) sequestration starts in both terminals at approximately 250 nM, exhibits a similar Ca(2+)-uptake affinity (approximately 410 nM), and does not require Ca(2+) release from the endoplasmic reticulum. Nonetheless, mitochondrial Ca(2+) uptake in type Is terminals is more responsive to low-frequency nerve stimulation and this is due to higher cytosolic Ca(2+) levels. Since type Ib terminals have a higher mitochondrial density than Is terminals, it seemed possible that greater mitochondrial Ca(2+) sequestration may be responsible for the lower cytosolic Ca(2+) levels in Ib terminals. However, genetic and pharmacological manipulations of mitochondrial Ca(2+) uptake did not significantly alter nerve-stimulated elevations in cytosolic Ca(2+) levels in either terminal type within physiologically relevant rates of stimulation. Our findings indicate that presynaptic mitochondria have a similar affinity for Ca(2+) in functionally different nerve terminals, but do not limit cytosolic Ca(2+) levels within the range of motor neuron firing rates in situ.
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Xiong Y, Singh IN, Hall ED. Tempol protection of spinal cord mitochondria from peroxynitrite-induced oxidative damage. Free Radic Res 2009; 43:604-12. [PMID: 19513907 DOI: 10.1080/10715760902977432] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Peroxynitrite (PN)-mediated mitochondrial dysfunction has been implicated in the secondary injury process after traumatic spinal cord injury (SCI). This study investigated the detrimental effects of the PN donor SIN-1 (3-morpholinosydnonimine) on isolated healthy spinal cord mitochondria and the protective effects of tempol, a catalytic scavenger of PN-derived radicals. A 5 min exposure of the mitochondria to SIN-1 caused a dose-dependent decrease in the respiratory control ratio (RCR) that was accompanied by significant increases in complex I-driven states II and IV respiration rates and decreases in states III and V. These impairments occurred together with an increase in mitochondrial protein 3-nitrotyrosine (3-NT), but not in lipid peroxidation (LP)-related 4-hydroxynonenal (4-HNE). Tempol significantly antagonized the respiratory effects of SIN-1 in parallel with an attenuation of 3-NT levels. These results show that the exogenous PN donor, SIN-1, rapidly causes mitochondrial oxidative damage and complex I dysfunction identical to traumatic spinal cord mitochondrial impairment and that this is mainly due to tyrosine nitration. Consistent with that, the protection of mitochondrial respiratory function by tempol is associated with a decrease in 3-NT levels in mitochondrial proteins also similar to the previously reported antioxidant actions of tempol in traumatically-injured spinal cord mitochondria.
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Affiliation(s)
- Yiqin Xiong
- Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536, USA
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A comparison of Zn2+- and Ca2+-triggered depolarization of liver mitochondria reveals no evidence of Zn2+-induced permeability transition. Cell Calcium 2009; 45:447-55. [PMID: 19349076 DOI: 10.1016/j.ceca.2009.03.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Revised: 02/28/2009] [Accepted: 03/03/2009] [Indexed: 01/27/2023]
Abstract
Intracellular Zn(2+) toxicity is associated with mitochondrial dysfunction. Zn(2+) depolarizes mitochondria in assays using isolated organelles as well as cultured cells. Some reports suggest that Zn(2+)-induced depolarization results from the opening of the mitochondrial permeability transition pore (mPTP). For a more detailed analysis of this relationship, we compared Zn(2+)-induced depolarization with the effects of Ca(2+) in single isolated rat liver mitochondria monitored with the potentiometric probe rhodamine 123. Consistent with previous work, we found that relatively low levels of Ca(2+) caused rapid, complete and irreversible loss of mitochondrial membrane potential, an effect that was diminished by classic inhibitors of mPT, including high Mg(2+), ADP and cyclosporine A. Zn(2+) also depolarized mitochondria, but only at relatively high concentrations. Furthermore Zn(2+)-induced depolarization was slower, partial and sometimes reversible, and was not affected by inhibitors of mPT. We also compared the effects of Ca(2+) and Zn(2+) in a calcein-retention assay. Consistent with the well-documented ability of Ca(2+) to induce mPT, we found that it caused rapid and substantial loss of matrix calcein. In contrast, calcein remained in Zn(2+)-treated mitochondria. Considered together, our results suggest that Ca(2+) and Zn(2+) depolarize mitochondria by considerably different mechanisms, that opening of the mPTP is not a direct consequence of Zn(2+)-induced depolarization, and that Zn(2+) is not a particularly potent mitochondrial inhibitor.
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Hazelton JL, Petrasheuskaya M, Fiskum G, Kristián T. Cyclophilin D is expressed predominantly in mitochondria of gamma-aminobutyric acidergic interneurons. J Neurosci Res 2009; 87:1250-9. [PMID: 18951528 PMCID: PMC2650012 DOI: 10.1002/jnr.21921] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Brain mitochondria are relatively resistant to calcium-induced mitochondrial permeability transition (MPT), with heterogenic response to the insult. The cause for this heterogeneity is not clear, so we studied the distribution of a key regulator of the MPT, cyclophilin D (cypD), within the rat brain by using immunohistology and Western blotting. Motor and parietal cortex, hippocampus, striatum, substantia nigra, ventral tegmental area, septum, and mammillary nucleus displayed a strong immunoreactivity to cypD within specific subpopulation of neurons. The staining was punctate and intense, particularly in perinuclear regions of cells. Apart from neurons, a subpopulation of astrocytes and NG2-positive cells showed higher cypD immunoreactivity. Double staining of cypD with cytochrome oxidase confirmed the mitochondrial specificity of cypD immunoreactivity. The neurons with high levels of cypD also expressed glutamate decarboxylase (GAD) and the calcium binding protein parvalbumin or calbinding D-28k, identifying these cells as interneurons. Western blots confirmed our immunohistochemical findings, showing significantly higher levels of cypD in crude mitochondria of substantia nigra compared with cortex or striatum. Furthermore, nonsynaptic mitochondria representing mainly mitochondria from cell bodies of neurons and glia have about 16% higher levels of cypD compared with synaptic mitochondria that are localized in presynaptic buttons. These data suggest that the underlying factor of heterogenic response of isolated brain mitochondria to MPT-inducing insults can be the different expression levels of cypD, with mitochondria originated from interneurons as the most sensitive.
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Affiliation(s)
- Julie L Hazelton
- Department of Anesthesiology Research, School of Medicine, University of Maryland, Baltimore, Maryland 21201, USA
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Nicholls DG. Mitochondrial calcium function and dysfunction in the central nervous system. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:1416-24. [PMID: 19298790 DOI: 10.1016/j.bbabio.2009.03.010] [Citation(s) in RCA: 169] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2008] [Revised: 03/09/2009] [Accepted: 03/10/2009] [Indexed: 12/17/2022]
Abstract
The ability of isolated brain mitochondria to accumulate, store and release calcium has been extensively characterized. Extrapolation to the intact neuron led to predictions that the in situ mitochondria would reversibly accumulate Ca(2+) when the concentration of the cation in the vicinity of the mitochondria rose above the 'set-point' at which uptake and efflux were in balance, storing Ca(2+) as a complex with phosphate, and slowly releasing the cation when plasma membrane ion pumps lowered the cytoplasmic free Ca(2+). Excessive accumulation of the cation was predicted to lead to activation of the permeability transition, with catastrophic consequences for the neuron. Each of these predictions has been confirmed with intact neurons, and there is convincing evidence for the permeability transition in cellular Ca(2+) overload associated with glutamate excitotoxicity and stroke, while the neurodegenerative disease in which possible defects in mitochondrial Ca(2+) handling have been most intensively investigated is Huntington's Disease. In this brief review evidence that mitochondrial Ca(2+) transport is relevant to neuronal survival in these conditions will be discussed.
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Affiliation(s)
- David G Nicholls
- Buck Institute for Age Research, 8001 Redwood Boulevard, Novato, CA 94945, USA.
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35
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Du G, Willet K, Jarmuszkiewicz W, Sluse-Goffart CM, Sluse FE. Protective Effect of EGb 761 Against Oxidative Phosphorylation of Brain Mitochondria After Anoxia/Reoxygenation In Vivo and In Vitro. Toxicol Mech Methods 2008; 14:97-101. [DOI: 10.1080/15376520490257455] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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36
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Cyclophilin D deficiency attenuates mitochondrial and neuronal perturbation and ameliorates learning and memory in Alzheimer's disease. Nat Med 2008; 14:1097-105. [PMID: 18806802 DOI: 10.1038/nm.1868] [Citation(s) in RCA: 723] [Impact Index Per Article: 45.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2008] [Accepted: 08/25/2008] [Indexed: 12/22/2022]
Abstract
Cyclophilin D (CypD, encoded by Ppif) is an integral part of the mitochondrial permeability transition pore, whose opening leads to cell death. Here we show that interaction of CypD with mitochondrial amyloid-beta protein (Abeta) potentiates mitochondrial, neuronal and synaptic stress. The CypD-deficient cortical mitochondria are resistant to Abeta- and Ca(2+)-induced mitochondrial swelling and permeability transition. Additionally, they have an increased calcium buffering capacity and generate fewer mitochondrial reactive oxygen species. Furthermore, the absence of CypD protects neurons from Abeta- and oxidative stress-induced cell death. Notably, CypD deficiency substantially improves learning and memory and synaptic function in an Alzheimer's disease mouse model and alleviates Abeta-mediated reduction of long-term potentiation. Thus, the CypD-mediated mitochondrial permeability transition pore is directly linked to the cellular and synaptic perturbations observed in the pathogenesis of Alzheimer's disease. Blockade of CypD may be a therapeutic strategy in Alzheimer's disease.
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37
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Uchino H, Kuroda Y, Morota S, Hirabayashi G, Ishii N, Shibasaki F, Ikeda Y, Hansson MJ, Elmér E. Probing the molecular mechanisms of neuronal degeneration: importance of mitochondrial dysfunction and calcineurin activation. J Anesth 2008; 22:253-62. [PMID: 18685932 DOI: 10.1007/s00540-008-0617-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2008] [Accepted: 02/09/2008] [Indexed: 01/19/2023]
Abstract
Cerebral injury is a critical aspect of the management of patients in intensive care. Pathological conditions induced by cerebral ischemia, hypoxia, head trauma, and seizure activity can result in marked residual impairment of cerebral function. We have investigated the potential mechanisms leading to neuronal cell death in pathological conditions, with the aim of discovering therapeutic targets and methods to minimize neuronal damage resulting from insults directed at the central nervous system (CNS). Over the years, deeper understanding of the mechanisms of neuronal cell death has indeed evolved, enabling clinical critical care management to salvage neurons that are at the brink of degeneration and to support recovery of brain function. However, no substantial breakthrough has been achieved in the quest to develop effective pharmacological neuroprotective therapy directed at tissues of the CNS. The current situation is unacceptable, and preservation of function and protection of the brain from terminal impairment will be a vital medical issue in the twenty-first century. To achieve this goal, it is critical to clarify the key mechanisms leading to neuronal cell death. Here, we discuss the importance of the calcineurin/immunophilin signal transduction pathway and mitochondrial involvement in the detrimental chain of events leading to neuronal degeneration.
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Affiliation(s)
- Hiroyuki Uchino
- Department of Anesthesiology, Hachioji Medical Center, Tokyo Medical University, 1163 Tate-machi, Hachioji, Tokyo 193-0998, Japan
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Leung AWC, Halestrap AP. Recent progress in elucidating the molecular mechanism of the mitochondrial permeability transition pore. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2008; 1777:946-52. [PMID: 18407825 DOI: 10.1016/j.bbabio.2008.03.009] [Citation(s) in RCA: 250] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Revised: 03/04/2008] [Accepted: 03/19/2008] [Indexed: 12/16/2022]
Abstract
The mitochondrial permeability transition pore (MPTP) plays a key role in cell death, especially necrosis, and mediates the injury tissues such as the heart and brain experience following ischaemia and reperfusion. However, the molecular identity of the MPTP remains uncertain. Knockout studies have confirmed a role for cyclophilin-D (CyP-D) in pore opening, probably mediated by its peptidyl-prolyl cis-trans isomerase activity that facilitates a conformational change in an inner membrane protein. However, similar knockout studies have cast doubt on the central role of the adenine nucleotide translocase (ANT), previously regarded as a leading contender for the membrane component that forms the transmembrane channel of the MPTP. Here we review the evidence for and against a role for the ANT in MPTP opening and conclude that it usually plays a regulatory role rather than provide the transmembrane pore component. We suggest that the protein fulfilling the latter role is the mitochondrial phosphate carrier (PiC) and summarise recent evidence in support of this proposal. Our data are consistent with a model for the MPTP in which a calcium-triggered conformational change of the PiC, facilitated by CyP-D, induces pore opening. We propose that this is enhanced by an association of the PiC with the "c" conformation of the ANT. Agents that modulate pore opening may act on either or both the PiC and the ANT.
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Affiliation(s)
- Anna W C Leung
- Department of Biochemistry and Bristol Heart Institute, University of Bristol, School of Medical Sciences, University Walk, Bristol BS8 1TD, UK
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Piwonska M, Wilczek E, Szewczyk A, Wilczynski GM. Differential distribution of Ca2+-activated potassium channel beta4 subunit in rat brain: immunolocalization in neuronal mitochondria. Neuroscience 2008; 153:446-60. [PMID: 18359571 DOI: 10.1016/j.neuroscience.2008.01.050] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2007] [Revised: 12/20/2007] [Accepted: 01/28/2008] [Indexed: 10/22/2022]
Abstract
Large conductance Ca(2+)-activated potassium channels (BK(Ca) channels) are expressed in the plasma membrane of various cell types. Interestingly, recent studies provided evidence for the existence of BK(Ca) channels also in mitochondria. However, the molecular composition of these channels as well as their cellular and tissue distribution is still unknown. The goal of the present study was to find a candidate for the regulatory component of the mitochondrial large conductance calcium activated potassium (mitoBK(Ca)) channel in neurons. A combined approach of Western blot analysis, high-resolution immunofluorescence and immunoelectron microscopy with the use of antibodies directed against four distinct beta subunits demonstrated the presence of the BK(Ca) channel beta4 subunit (KCNMB4) in the inner membrane of neuronal mitochondria in the rat brain and cultured neurons. Within the cell, the expression of beta4 subunit was restricted to a subpopulation of mitochondria. The analysis of beta4 subunit distribution throughout the brain revealed that the highest expression levels occur in the thalamus and the brainstem. Our results suggest that beta4 subunit is a regulatory component of mitochondrial BK(Ca) channels in neurons. These findings may support the perspectives for the neuroprotective role of mitochondrial BK(Ca) channel in specific brain structures.
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Affiliation(s)
- M Piwonska
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, 3 Pasteur Street, Warsaw, Poland
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Chabrier PE, Auguet M. Pharmacological properties of BN82451: a novel multitargeting neuroprotective agent. CNS DRUG REVIEWS 2008; 13:317-32. [PMID: 17894648 PMCID: PMC6494126 DOI: 10.1111/j.1527-3458.2007.00018.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BN82451 belongs to a new family of small molecules designated as multitargeting or hybrid molecules. BN82451 is orally active, has good central nervous system penetration, and elicits potent neuronal protection and antiinflammatory properties. Neuronal protection is due to Na+ channel blockade, antioxidant properties, and mitochondria-protecting activity, whereas inhibition of cyclooxygenases is mostly responsible for its antiinflammatory activity. BN82451 has been shown to exert a potent neuroprotective effect in various in vitro and in vivo animal models. BN82451 was found to exert a significant protection in experimental animal models mimicking aspects of cerebral ischemia, Parkinson disease, Huntington disease, and more particularly amyotrophic lateral sclerosis. Collectively, its pharmacological properties designate BN82451 as a promising neuroprotective agent.
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41
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Contribution of calpain activation to early stages of hippocampal damage during oxygen–glucose deprivation. Brain Res 2008; 1196:121-30. [DOI: 10.1016/j.brainres.2007.12.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2007] [Revised: 11/30/2007] [Accepted: 12/01/2007] [Indexed: 01/19/2023]
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Morota S, Hansson MJ, Ishii N, Kudo Y, Elmér E, Uchino H. Spinal cord mitochondria display lower calcium retention capacity compared with brain mitochondria without inherent differences in sensitivity to cyclophilin D inhibition. J Neurochem 2007; 103:2066-76. [PMID: 17868326 DOI: 10.1111/j.1471-4159.2007.04912.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The mitochondrial permeability transition (mPT) is a potential pathogenic mechanism in neurodegeneration. Varying sensitivity to calcium-induced mPT has been demonstrated for regions within the CNS possibly correlating with vulnerability following insults. The spinal cord is selectively vulnerable in e.g. amyotrophic lateral sclerosis and increased mPT sensitivity of mitochondria derived from the spinal cord has previously been demonstrated. In this study, we introduce whole-body hypothermia prior to removal of CNS tissue to minimize the effects of differential tissue extraction prior to isolation of spinal cord and cortical brain mitochondria. Spinal cord mitochondria were able to retain considerably less calcium when administered as continuous infusion, which was not related to a general increased sensitivity of the mPT to calcium, its desensitization to calcium by the cyclophilin D inhibitor cyclosporin-A, or to differences in respiratory parameters. Spinal cord mitochondria maintained a higher concentration of extramitochondrial calcium during infusion than brain mitochondria possibly related to an increased set-point concentration for calcium uptake. A hampered transport and retention capacity of calcium may translate into an increased susceptibility of the spinal cord to neurodegenerative processes involving calcium-mediated damage.
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Affiliation(s)
- Saori Morota
- Department of Anesthesiology, Tokyo Medical University Hachioji Medical Center, Tatemachi, Hachioji, Japan
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Nakai A. Role of mitochondrial permeability transition in the immature brain following intrauterine ischemia. J NIPPON MED SCH 2007; 74:190-201. [PMID: 17625367 DOI: 10.1272/jnms.74.190] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Recirculation following 30 minutes of intrauterine ischemia due to uterine artery occlusion has previously been found to be accompanied by delayed deterioration of the cellular bioenergetic state and of mitochondrial function in the fetal rat brain. The objective of this study was to assess whether the delayed deterioration is due to the activation of mitochondrial permeability transition (MPT), which is observed ultrastructurally as mitochondrial swelling. The respiratory activities and ultrastructure of isolated mitochondria and the cellular bioenergetic state in the fetal rat brain were examined at the end of 30 minutes of intrauterine ischemia and after 1, 2, 3 or 4 hours of recirculation. Cyclosporin A (CsA), a potent and specific MPT blocker, or vehicle was given 1 hour after recirculation. In the vehicle-treated animals, the transient ischemia was associated with a delayed deterioration of the cellular bioenergetic state and mitochondrial activities 4 hours of recirculation. The number of swollen mitochondria increased markedly after 4 hours of recirculation. Both the deterioration and swelling were prevented by CsA. The present study indicates that treatment with CsA improves recovery of energy metabolism and inhibits mitochondrial swelling following transient intrauterine ischemia in the fetal brain. The results suggest that mitochondria and MPT may be involved in the development of ischemic brain damage in the immature rat.
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Affiliation(s)
- Akihito Nakai
- Department of Female Reproductive and Developmental Medicine, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
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Abstract
Irrespective of the morphological features of end-stage cell death (that may be apoptotic, necrotic, autophagic, or mitotic), mitochondrial membrane permeabilization (MMP) is frequently the decisive event that delimits the frontier between survival and death. Thus mitochondrial membranes constitute the battleground on which opposing signals combat to seal the cell's fate. Local players that determine the propensity to MMP include the pro- and antiapoptotic members of the Bcl-2 family, proteins from the mitochondrialpermeability transition pore complex, as well as a plethora of interacting partners including mitochondrial lipids. Intermediate metabolites, redox processes, sphingolipids, ion gradients, transcription factors, as well as kinases and phosphatases link lethal and vital signals emanating from distinct subcellular compartments to mitochondria. Thus mitochondria integrate a variety of proapoptotic signals. Once MMP has been induced, it causes the release of catabolic hydrolases and activators of such enzymes (including those of caspases) from mitochondria. These catabolic enzymes as well as the cessation of the bioenergetic and redox functions of mitochondria finally lead to cell death, meaning that mitochondria coordinate the late stage of cellular demise. Pathological cell death induced by ischemia/reperfusion, intoxication with xenobiotics, neurodegenerative diseases, or viral infection also relies on MMP as a critical event. The inhibition of MMP constitutes an important strategy for the pharmaceutical prevention of unwarranted cell death. Conversely, induction of MMP in tumor cells constitutes the goal of anticancer chemotherapy.
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Affiliation(s)
- Guido Kroemer
- Institut Gustave Roussy, Institut National de la Santé et de la Recherche Médicale Unit "Apoptosis, Cancer and Immunity," Université de Paris-Sud XI, Villejuif, France
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Chang DTW, Reynolds IJ. Mitochondrial trafficking and morphology in healthy and injured neurons. Prog Neurobiol 2006; 80:241-68. [PMID: 17188795 DOI: 10.1016/j.pneurobio.2006.09.003] [Citation(s) in RCA: 170] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2006] [Revised: 09/14/2006] [Accepted: 09/18/2006] [Indexed: 12/21/2022]
Abstract
Mitochondria are the primary generators of ATP and are important regulators of intracellular calcium homeostasis. These organelles are dynamically transported along lengthy neuronal processes, presumably for appropriate distribution to cellular regions of high metabolic demand and elevated intracellular calcium, such as synapses. The removal of damaged mitochondria that produce harmful reactive oxygen species and promote apoptosis is also thought to be mediated by transport of mitochondria to autophagosomes. Mitochondrial trafficking is therefore important for maintaining neuronal and mitochondrial health while cessation of movement may lead to neuronal and mitochondrial dysfunction. Mitochondrial morphology is also dynamic and is remodeled during neuronal injury and disease. Recent studies reveal different manifestations and mechanisms of impaired mitochondrial movement and altered morphology in injured neurons. These are likely to cause varied courses toward neuronal degeneration and death. The goal of this review is to provide an appreciation of the full range of mitochondrial function, morphology and trafficking, and the critical role these parameters play in neuronal physiology and pathophysiology.
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Affiliation(s)
- Diane T W Chang
- Medical Scientist Training Program, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
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Abstract
When mitochondria are exposed to high Ca2+ concentrations, especially when accompanied by oxidative stress and adenine nucleotide depletion, they undergo massive swelling and become uncoupled. This occurs as a result of the opening of a non-specific pore in the inner mitochondrial membrane, known as the MPTP (mitochondrial permeability transition pore). If the pore remains open, cells cannot maintain their ATP levels and this will lead to cell death by necrosis. This article briefly reviews what is known of the molecular mechanism of the MPTP and its role in causing the necrotic cell death of the heart and brain that occurs during reperfusion after a long period of ischaemia. Such reperfusion injury is a major problem during cardiac surgery and in the treatment of coronary thrombosis and stroke. Prevention of MPTP opening either directly, using agents such as cyclosporin A, or indirectly by reducing oxidative stress or Ca2+ overload, provides a protective strategy against reperfusion injury. Furthermore, mice in which a component of the MPTP, CyP-D (cyclophilin D), has been knocked out are protected against heart and brain ischaemia/reperfusion. When cells experience a less severe insult, the MPTP may open transiently. The resulting mitochondrial swelling may be sufficient to cause release of cytochrome c and activation of the apoptotic pathway rather than necrosis. However, the CyP-D-knockout mice develop normally and show no protection against a range of apoptotic stimuli, suggesting that the MPTP does not play a role in most forms of apoptosis.
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Brown MR, Sullivan PG, Geddes JW. Synaptic mitochondria are more susceptible to Ca2+overload than nonsynaptic mitochondria. J Biol Chem 2006; 281:11658-68. [PMID: 16517608 DOI: 10.1074/jbc.m510303200] [Citation(s) in RCA: 217] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Mitochondria in nerve terminals are subjected to extensive Ca2+ fluxes and high energy demands, but the extent to which the synaptic mitochondria buffer Ca2+ is unclear. In this study, we identified a difference in the Ca2+ clearance ability of nonsynaptic versus synaptic mitochondrial populations enriched from rat cerebral cortex. Mitochondria were isolated using Percoll discontinuous gradients in combination with high pressure nitrogen cell disruption. Mitochondria in the nonsynaptic fraction originate from neurons and other cell types including glia, whereas mitochondria enriched from a synaptosomal fraction are predominantly neuronal and presynaptic in origin. There were no differences in respiration or initial Ca2+ loads between nonsynaptic and synaptic mitochondrial populations. Following both bolus and infusion Ca2+ addition, nonsynaptic mitochondria were able to accumulate significantly more exogenously added Ca2+ than the synaptic mitochondria before undergoing mitochondrial permeability transition, observed as a loss in mitochondrial membrane potential and decreased Ca2+ uptake. The limited ability of synaptic mitochondria to accumulate Ca2+ could result from several factors including a primary function of ATP production to support the high energy demand of presynaptic terminals, their relative isolation in comparison with the threads or clusters of mitochondria found in the soma of neurons and glia, or the older age and increased exposure to oxidative damage of synaptic versus nonsynaptic mitochondria. By more readily undergoing permeability transition, synaptic mitochondria may initiate neuron death in response to insults that elevate synaptic levels of intracellular Ca2+, consistent with the early degeneration of distal axon segments in neurodegenerative disorders.
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Affiliation(s)
- Maile R Brown
- Graduate Center for Gerontology, Sanders-Brown Center on Aging, Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536-0509, USA
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Lifshitz J, Janmey PA, McIntosh TK. Photon correlation spectroscopy of brain mitochondrial populations: Application to traumatic brain injury. Exp Neurol 2006; 197:318-29. [PMID: 16289540 DOI: 10.1016/j.expneurol.2005.10.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2005] [Revised: 08/29/2005] [Accepted: 10/12/2005] [Indexed: 01/27/2023]
Abstract
Mitochondrial dysfunction and pathology that contribute to a host of neurodegenerative diseases are deduced from changes in ultrastructure, routinely examined by a host of optical techniques. We adapted the technique of photon correlation spectroscopy (PCS) to evaluate calcium-induced structural alterations in isolated viable cortical and hippocampal mitochondria. In detecting calcium-induced reductions in light intensity, PCS was more sensitive than absorbance across varying calcium concentrations. Mitochondrial populations encompass a broad distribution of sizes, confirmed by ultrastructural profiles, both which remain unaffected by calcium exposure. Cortical and hippocampal populations show fractional calcium-induced reductions in light scatter compared to subsequent maximal alamethicin-induced reductions. Although reductions in light scatter (refractive index) have been interpreted as mitochondrial swelling, PCS quantification of the mean mitochondrial radius demonstrates that mitochondrial size is unaffected by calcium exposure, but not alamethicin. Likewise, the population distribution histograms remain stable with calcium exposure, but shift to larger radii after alamethicin exposure. Furthermore, hippocampal mitochondrial populations from a neurodegenerative model of traumatic brain injury, lateral fluid percussion, demonstrate greater calcium-induced reductions in scatter intensity, which are associated with an initial population of large mitochondria becoming smaller. The disparate responses to calcium and subsequent alamethicin of mitochondria at 3 and 24 h after injury attest to an acute disruption of membrane permeability in mitochondria from injured brain. PCS provides quantitative indices of refractive index and size in isolated mitochondrial populations, aiding the evaluation of mitochondria in degenerative diseases.
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Affiliation(s)
- Jonathan Lifshitz
- Traumatic Brain Injury Laboratory, Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Blomgren K, Hagberg H. Free radicals, mitochondria, and hypoxia-ischemia in the developing brain. Free Radic Biol Med 2006; 40:388-97. [PMID: 16443153 DOI: 10.1016/j.freeradbiomed.2005.08.040] [Citation(s) in RCA: 217] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2005] [Revised: 08/01/2005] [Accepted: 08/24/2005] [Indexed: 11/17/2022]
Abstract
The immature brain is particularly susceptible to free radical injury because of its poorly developed scavenging systems and high availability of iron for the catalytic formation of free radicals. Neurons are more vulnerable to free radical damage than glial cells, but oligodendrocyte progenitors and immature oligodendrocytes in very prematurely born infants are selectively vulnerable to depletion of antioxidants and free radical attack. Reactive oxygen and nitrogen species play important roles in the initiation of apoptotic mechanisms and in mitochondrial permeability transition, and therefore constitute important targets for therapeutic intervention. Oxidative stress is an early feature after cerebral ischemia and experimental studies targeting the formation of free radicals demonstrate various degrees of protection after perinatal insults. Oxidative stress-regulated release of proapoptotic factors from mitochondria appears to play a much more important role in the immature brain. This review will summarize and compare with the adult brain some of the current knowledge of free radical formation in the developing brain and its roles in the pathophysiology after cerebral hypoxia-ischemia.
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Affiliation(s)
- Klas Blomgren
- Arvid Carlsson Institute, Sahlgrenska Academy, Göteborg University, Sweden.
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Uchino H, Morota S, Takahashi T, Ikeda Y, Kudo Y, Ishii N, Siesjö BK, Shibasaki F. A novel neuroprotective compound FR901459 with dual inhibition of calcineurin and cyclophilins. ACTA NEUROCHIRURGICA. SUPPLEMENT 2006; 96:157-62. [PMID: 16671446 DOI: 10.1007/3-211-30714-1_35] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Brain ischemia leads to severe damage in the form of delayed neuronal cell death. In our study, we show that the marked neuroprotection of the new immunosuppressant FR901495 in forebrain ischemia is due not only to inhibition of calcineurin, but also to protection against mitochondrial damage caused by mitochondrial permeability transition pore formation through cyclophilin D, one of the prolyl cis/trans isomerase family members. These findings shed light on the clinical application and development of new drugs for the treatment of ischemic damage in the brain as well as in the heart and liver.
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Affiliation(s)
- H Uchino
- Department of Anesthesiology, Hachioji Medical Center, Tokyo Medical University, Tokyo, Japan.
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