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Tuboly E, Szabó A, Garab D, Bartha G, Janovszky Á, Erős G, Szabó A, Mohácsi Á, Szabó G, Kaszaki J, Ghyczy M, Boros M. Methane biogenesis during sodium azide-induced chemical hypoxia in rats. Am J Physiol Cell Physiol 2012; 304:C207-14. [PMID: 23174561 DOI: 10.1152/ajpcell.00300.2012] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous studies demonstrated methane generation in aerobic cells. Our aims were to investigate the methanogenic features of sodium azide (NaN(3))-induced chemical hypoxia in the whole animal and to study the effects of l-α-glycerylphosphorylcholine (GPC) on endogenous methane production and inflammatory events as indicators of a NaN(3)-elicited mitochondrial dysfunction. Group 1 of Sprague-Dawley rats served as the sham-operated control; in group 2, the animals were treated with NaN(3) (14 mg·kg(-1)·day(-1) sc) for 8 days. In group 3, the chronic NaN(3) administration was supplemented with daily oral GPC treatment. Group 4 served as an oral antibiotic-treated control (rifaximin, 10 mg·kg(-1)·day(-1)) targeting the intestinal bacterial flora, while group 5 received this antibiotic in parallel with NaN(3) treatment. The whole body methane production of the rats was measured by means of a newly developed method based on photoacoustic spectroscopy, the microcirculation of the liver was observed by intravital videomicroscopy, and structural changes were assessed via in vivo fluorescent confocal laser-scanning microscopy. NaN(3) administration induced a significant inflammatory reaction and methane generation independently of the methanogenic flora. After 8 days, the hepatic microcirculation was disturbed and the ATP content was decreased, without major structural damage. Methane generation, the hepatic microcirculatory changes, and the increased tissue myeloperoxidase and xanthine oxidoreductase activities were reduced by GPC treatment. In conclusion, the results suggest that methane production in mammals is connected with hypoxic events associated with a mitochondrial dysfunction. GPC is protective against the inflammatory consequences of a hypoxic reaction that might involve cellular or mitochondrial methane generation.
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Affiliation(s)
- Eszter Tuboly
- Institute of Surgical Research, Faculty of Medicine, University of Szeged, Szeged, Hungary
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202
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He XL, Zhang P, Dong XZ, Yang MH, Chen SL, Bi MG. JR6, a new compound isolated from Justicia procumbens, induces apoptosis in human bladder cancer EJ cells through caspase-dependent pathway. JOURNAL OF ETHNOPHARMACOLOGY 2012; 144:284-292. [PMID: 22985636 DOI: 10.1016/j.jep.2012.09.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 07/24/2012] [Accepted: 09/03/2012] [Indexed: 06/01/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Numerous efforts have been conducted in searching for effective agents against cancer, in particular from herbal medicines. Justicia procumbens is a traditional herbal remedy which was produced in the south-western and southern provinces of China and Taiwan province used to treat fever, pain, and cancer. Here, we identified a new compound 6'-hydroxy justicidin A (JR6) from Justicia procumbens, which showed obvious anti-cancer effects. MATERIALS AND METHODS The cytotoxicity activity was assayed using MTT and SRB. Intracellular ROS visualization and quantification were acquired by using a laser scanning confocal microscopy. Apoptosis was measured using a propidium iodide (PI) apoptosis detection kit by flow cytometry. Activation of caspases (caspase-3, caspase-8, and caspase-9) was evaluated respectively using GloMax luminescence detector and Caspase-Glo 3,8,9 assay kits. Loss of mitochondrial membrane potential was observed by microscopy using JC-1 dye. Quantitative real-time PCR analysis was employed to detect the expression of protein associated with cell death. RESULTS JR6 remarkably inhibited growth in human bladder cancer EJ cells by decreasing cell proliferation, reduced the SOD activity, increased the content of reactive oxygen species (ROS), and induced apoptosis. Activation of caspase-8, caspase-9, and the subsequent activation of caspase-3 indicated that JR6 may be inducing intrinsic and extrinsic apoptosis pathways. Caspase-3, caspase-8, and caspase-9 inhibition rendered this extract ineffective, thus JR6-induced apoptosis is caspase-dependent. JR6 also disrupted the mitochondrial membrane potential (Δψm) and unregulated the Bax and p53 expressions in EJ cells. CONCLUSION These observations suggest that JR6 induce apoptosis through caspase-dependent pathway in human bladder cancer EJ cells, emphasizing the importance of this traditional medicine and thus presents a potential novel alternative to bladder cancer therapy.
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Affiliation(s)
- Xiao-Li He
- Research Center for Pharmacology and Toxicology, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 151 Malianwa North Road, Haidian District, Beijing, China
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203
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Ataya B, Tzeng E, Zuckerbraun BS. Nitrite-generated nitric oxide to protect against intimal hyperplasia formation. Trends Cardiovasc Med 2012; 21:157-62. [PMID: 22814422 DOI: 10.1016/j.tcm.2012.05.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Vascular disease is a leading cause of morbidity and mortality worldwide. Current vascular therapeutic interventions directed at diseased vessels are restricted in long-term efficacy by the development of intimal hyperplasia and the reformation of flow-limiting disease. The vascular injury and inflammation that ensues from the intervention, especially in the setting of an existing atherosclerotic vascular disease, results in further endothelial dysfunction and subsequent smooth muscle cell proliferation and migration. Although the etiology of intimal hyperplasia is multifactorial, impaired nitric oxide (NO) signaling has been implicated. The vasoprotective properties of NO have been intensely studied, and many investigations have focused on harnessing this biological system for therapeutic benefit. Continued studies investigate the role of impaired NO signaling via the classical arginine/NO synthase (NOS)/NO pathway in the setting of intimal hyperplasia. Furthermore, the possible protective effects of nitrate and nitrite-generated NO via non-NOS-mediated pathways to limit vascular injury have been recently appreciated and will likely prove to be an important vasoregulatory and vasoprotective signaling pathway.
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Affiliation(s)
- Bilal Ataya
- University of Pittsburgh, Pittsburgh, PA 15240, USA
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204
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Inhaled Nitric Oxide Protects Males But not Females from Neonatal Mouse Hypoxia–Ischemia Brain Injury. Transl Stroke Res 2012; 4:201-7. [DOI: 10.1007/s12975-012-0217-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 10/08/2012] [Accepted: 10/10/2012] [Indexed: 12/22/2022]
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205
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Anabolic-androgenic steroids induce apoptosis and NOS2 (nitric-oxide synthase 2) in adult rat Leydig cells following in vivo exposure. Reprod Toxicol 2012; 34:686-93. [PMID: 23085480 DOI: 10.1016/j.reprotox.2012.10.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 08/31/2012] [Accepted: 10/02/2012] [Indexed: 01/13/2023]
Abstract
Anabolic-androgenic steroids (AAS) are synthetic derivatives of testosterone (T) predominantly taken as drugs of abuse. Using in vivo treatment of adult male rats we investigated the effects of testosterone enanthate (TE) a widely abused AAS, on apoptosis of Leydig cells. Increased T and decreased luteinizing hormone levels in serum and decreased intra-testicular T values were found in 2 and 10 weeks treated groups. Two weeks of TE-treatment stimulated the expression of inducible nitric oxide synthase (NOS2) followed by increased NO production, decreased mitochondrial membrane potential and increased prevalence of Leydig cell apoptosis. This was prevented by in vivo administration of androgen receptor blocker. The induced NOS2 level and apoptosis returned to control levels after 10 weeks of TE-treatment but testes contained fewer Leydig cells. Overall, AAS in addition to reduced steroidogenesis induce transient increase of Leydig cells apoptotic rate through mechanism associated with androgen receptor, most likely involving NOS2 induction.
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206
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Lambertucci RH, Leandro CG, Vinolo MA, Nachbar RT, dos Reis Silveira L, Hirabara SM, Curi R, Pithon-Curi TC. The Effects of Palmitic Acid on Nitric Oxide Production by Rat Skeletal Muscle: Mechanism via Superoxide and iNOS Activation. Cell Physiol Biochem 2012; 30:1169-80. [DOI: 10.1159/000343307] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2012] [Indexed: 01/05/2023] Open
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207
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Mongin AA, Dohare P, Jourd'heuil D. Selective vulnerability of synaptic signaling and metabolism to nitrosative stress. Antioxid Redox Signal 2012; 17:992-1012. [PMID: 22339371 PMCID: PMC3411350 DOI: 10.1089/ars.2012.4559] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
SIGNIFICANCE Nitric oxide (NO) plays diverse physiological roles in the central nervous system, where it modulates neuronal communication, regulates blood flow, and contributes to the innate immune responses. In a number of brain pathologies, the excessive production of NO also leads to the formation of reactive and toxic intermediates generically termed reactive nitrogen species (RNS). RNS cause irreversible or poorly reversible damage to brain cells. RECENT ADVANCES Recent work in the field focused on the ability of NO and RNS to yield protein modifications, including the S-nitrosation of cysteine residues, which, in many instances, impact cellular functions and viability. CRITICAL ISSUES The vast majority of neuropathological studies focus on the loss of cell viability, but nitrosative stress may also strongly impair the functions of neuronal processes: axonal projections and dendritic trees. The functional integrity of axons and dendrites critically depends on local metabolism and effective delivery of metabolic enzymes and organelles. Here, we summarize the existing literature describing the effects of nitrosative stress on the major pathways of energetic metabolism: glycolysis, tricarboxylic acid cycle, and mitochondrial respiration, with the emphasis on modifications of protein thiols. FUTURE DIRECTIONS We propose that axons and dendrites are highly vulnerable to nitrosative stress because of their low glycolytic capacity and high dependence on timely delivery of metabolic enzymes and organelles from the cell body. Thus, supplementation with the end products of glycolysis, pyruvate or lactate, may help preserve metabolism in distal neuronal processes and protect or restore synaptic function in the ailing brain.
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Affiliation(s)
- Alexander A Mongin
- Center for Neuropharmacology and Neuroscience, Albany Medical College, New York 12208, USA.
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208
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Zaobornyj T, Ghafourifar P. Strategic localization of heart mitochondrial NOS: a review of the evidence. Am J Physiol Heart Circ Physiol 2012; 303:H1283-93. [PMID: 23023869 DOI: 10.1152/ajpheart.00674.2011] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Heart mitochondria play a central role in cell energy provision and in signaling. Nitric oxide (NO) is a free radical with primary regulatory functions in the heart and involved in a broad array of key processes in cardiac metabolism. Specific NO synthase (NOS) isoforms are confined to distinct locations in cardiomyocytes. The present article reviews the chemical reactions through which NO interacts with biomolecules and exerts some of its crucial roles. Specifically, the article discusses the reactions of NO with mitochondrial targets and the subcellular localization of NOS within the myocardium and analyzes the available data about heart mitochondrial NOS activity and identity. The article also describes the regulation of heart mtNOS by the distinctive mitochondrial environment by showing the effects of Ca(2+), O(2), l-arginine, mitochondrial transmembrane potential, and the metabolic states on heart mitochondrial NO production. The article depicts the effects of NO on heart function and highlights the relevance of NO production within mitochondria. Finally, the evidence on the functional implications of heart mitochondrial NOS is delineated with emphasis on chronic hypoxia and ischemia-reperfusion studies.
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Affiliation(s)
- Tamara Zaobornyj
- Laboratory of Free Radical Biology, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina.
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209
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Al-Gubory KH, Garrel C, Faure P, Sugino N. Roles of antioxidant enzymes in corpus luteum rescue from reactive oxygen species-induced oxidative stress. Reprod Biomed Online 2012; 25:551-60. [PMID: 23063822 DOI: 10.1016/j.rbmo.2012.08.004] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 05/02/2012] [Accepted: 08/21/2012] [Indexed: 11/17/2022]
Abstract
Progesterone produced by the corpus luteum (CL) regulates the synthesis of various endometrial proteins required for embryonic implantation and development. Compromised CL progesterone production is a potential risk factor for prenatal development. Reactive oxygen species (ROS) play diverse roles in mammalian reproductive biology. ROS-induced oxidative damage and subsequent adverse developmental outcomes constitute important issues in reproductive medicine. The CL is considered to be highly exposed to locally produced ROS due to its high blood vasculature and steroidogenic activity. ROS-induced apoptotic cell death is involved in the mechanisms of CL regression that occurs at the end of the non-fertile cycle. Luteal ROS production and propagation depend upon several regulating factors, including luteal antioxidants, steroid hormones and cytokines, and their crosstalk. However, it is unknown which of these factors have the greatest contribution to the maintenance of CL integrity and function during the oestrous/menstrual cycle. There is evidence to suggest that antioxidants play important roles in CL rescue from luteolysis when pregnancy ensues. As luteal phase defect impacts fertility by preventing implantation and early conceptus development in livestock and humans, this review attempts to address the importance of ROS-scavenging antioxidant enzymes in the control of mammalian CL function and integrity. The corpus luteum (CL) is a transient endocrine organ that develops after ovulation from the ovulated follicle during each reproductive cycle. The main function of the CL is the production and secretion of progesterone which is necessary for embryonic implantation and development. Compromised CL progesterone production is a potential risk factor for prenatal development and pregnancy outcomes. Reactive oxygen species (ROS), which are natural by-products of cellular respiration and metabolism, play diverse roles in mammalian reproductive biology. ROS-induced oxidative damage and subsequent development of adverse pregnancy outcomes constitute important issues in reproductive medicine. Before the end of the first trimester, a high rate of human and animal conceptions end in spontaneous abortion and most of these losses occur at the time of implantation in association with ROS-induced oxidative damage. Every cell in the body is normally able to defend itself against the oxidative damage caused by the ROS. The cellular antioxidant enzymes constitute the first line of defence against the toxic effects of ROS. The CL is considered to be highly exposed to locally produced ROS due to its high blood vasculature and metabolic activity. There is now evidence to suggest that cellular antioxidants play important roles in CL rescue from regression when pregnancy ensues. As defective CL function impacts fertility by preventing implantation and early conceptus development in livestock and humans, this review attempts to address the importance of antioxidant enzymes in the control of mammalian CL function and integrity.
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Affiliation(s)
- Kaïs H Al-Gubory
- Institut National de la Recherche Agronomique, UMR 1198 Biologie du Développement et Reproduction, Département de Physiologie Animale et systèmes d'élevage, F-78350 Jouy-en-Josas, France.
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210
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Di Giacomo G, Rizza S, Montagna C, Filomeni G. Established Principles and Emerging Concepts on the Interplay between Mitochondrial Physiology and S-(De)nitrosylation: Implications in Cancer and Neurodegeneration. Int J Cell Biol 2012; 2012:361872. [PMID: 22927857 PMCID: PMC3425078 DOI: 10.1155/2012/361872] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Accepted: 06/19/2012] [Indexed: 01/10/2023] Open
Abstract
S-nitrosylation is a posttranslational modification of cysteine residues that has been frequently indicated as potential molecular mechanism governing cell response upon redox unbalance downstream of nitric oxide (over)production. In the last years, increased levels of S-nitrosothiols (SNOs) have been tightly associated with the onset of nitroxidative stress-based pathologies (e.g., cancer and neurodegeneration), conditions in which alterations of mitochondrial homeostasis and activation of cellular processes dependent on it have been reported as well. In this paper we aim at summarizing the current knowledge of mitochondria-related proteins undergoing S-nitrosylation and how this redox modification might impact on mitochondrial functions, whose impairment has been correlated to tumorigenesis and neuronal cell death. In particular, emphasis will be given to the possible, but still neglected implication of denitrosylation reactions in the modulation of mitochondrial SNOs and how they can affect mitochondrion-related cellular process, such as oxidative phosphorylation, mitochondrial dynamics, and mitophagy.
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Affiliation(s)
- Giuseppina Di Giacomo
- Research Centre IRCCS San Raffaele Pisana, Via di Val Cannuta, 247, 00166 Rome, Italy
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211
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McConell GK, Rattigan S, Lee-Young RS, Wadley GD, Merry TL. Skeletal muscle nitric oxide signaling and exercise: a focus on glucose metabolism. Am J Physiol Endocrinol Metab 2012; 303:E301-7. [PMID: 22550064 DOI: 10.1152/ajpendo.00667.2011] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nitric oxide (NO) is an important vasodilator and regulator in the cardiovascular system, and this link was the subject of a Nobel prize in 1998. However, NO also plays many other regulatory roles, including thrombosis, immune function, neural activity, and gastrointestinal function. Low concentrations of NO are thought to have important signaling effects. In contrast, high concentrations of NO can interact with reactive oxygen species, causing damage to cells and cellular components. A less-recognized site of NO production is within skeletal muscle, where small increases are thought to have beneficial effects such as regulating glucose uptake and possibly blood flow, but higher levels of production are thought to lead to deleterious effects such as an association with insulin resistance. This review will discuss the role of NO in skeletal muscle during and following exercise, including in mitochondrial biogenesis, muscle efficiency, and blood flow with a particular focus on its potential role in regulating skeletal muscle glucose uptake during exercise.
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Affiliation(s)
- Glenn K McConell
- Institute of Sport, Exercise and Active Living and the School of Biomedical and Health Sciences, Victoria University, Footscray, Victoria, Australia.
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212
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Jacobsen SB, Hansen MN, Jensen FB, Skovgaard N, Wang T, Fago A. Circulating nitric oxide metabolites and cardiovascular changes in the turtle Trachemys scripta during normoxia, anoxia and reoxygenation. J Exp Biol 2012; 215:2560-6. [DOI: 10.1242/jeb.070367] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
SUMMARY
Turtles of the genus Trachemys show a remarkable ability to survive prolonged anoxia. This is achieved by a strong metabolic depression, redistribution of blood flow and high levels of antioxidant defence. To understand whether nitric oxide (NO), a major regulator of vasodilatation and oxygen consumption, may be involved in the adaptive response of Trachemys to anoxia, we measured NO metabolites (nitrite, S-nitroso, Fe-nitrosyl and N-nitroso compounds) in the plasma and red blood cells of venous and arterial blood of Trachemys scripta turtles during normoxia and after anoxia (3 h) and reoxygenation (30 min) at 21°C, while monitoring blood oxygen content and circulatory parameters. Anoxia caused complete blood oxygen depletion, decrease in heart rate and arterial pressure, and increase in venous pressure, which may enhance heart filling and improve cardiac contractility. Nitrite was present at high, micromolar levels in normoxic blood, as in some other anoxia-tolerant species, without significant arterial–venous differences. Normoxic levels of erythrocyte S-nitroso compounds were within the range found for other vertebrates, despite very high measured thiol content. Fe-nitrosyl and N-nitroso compounds were present at high micromolar levels under normoxia and increased further after anoxia and reoxygenation, suggesting NO generation from nitrite catalysed by deoxygenated haemoglobin, which in turtle had a higher nitrite reductase activity than in hypoxia-intolerant species. Taken together, these data indicate constitutively high circulating levels of NO metabolites and significant increases in blood NO after anoxia and reoxygenation that may contribute to the complex physiological response in the extreme anoxia tolerance of Trachemys turtles.
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Affiliation(s)
- Søren B. Jacobsen
- Zoophysiology, Department of Bioscience, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Marie N. Hansen
- Institute of Biology, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Frank B. Jensen
- Institute of Biology, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Nini Skovgaard
- Zoophysiology, Department of Bioscience, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Tobias Wang
- Zoophysiology, Department of Bioscience, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Angela Fago
- Zoophysiology, Department of Bioscience, Aarhus University, DK-8000 Aarhus C, Denmark
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213
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Nitric oxide in myogenesis and therapeutic muscle repair. Mol Neurobiol 2012; 46:682-92. [PMID: 22821188 DOI: 10.1007/s12035-012-8311-8] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Accepted: 07/12/2012] [Indexed: 12/20/2022]
Abstract
Nitric oxide is a short-lived intracellular and intercellular messenger. The first realisation that nitric oxide is important in physiology occurred in 1987 when its identity with the endothelium-derived relaxing factor was discovered. Subsequent studies have shown that nitric oxide possesses a number of physiological functions that are essential not only to vascular homeostasis but also to neurotransmission, such as in the processes of learning and memory and endocrine gland regulation, as well as inflammation and immune responses. The discovery in 1995 that a splice variant of the neuronal nitric oxide synthase is localised at the sarcolemma via the dystrophin-glycoprotein complex and of its displacement in Duchenne muscular dystrophy has stimulated a host of studies exploring the role of nitric oxide in skeletal muscle physiology. Recently, nitric oxide has emerged as a relevant messenger also of myogenesis that it regulates at several key steps, especially when the process is stimulated for muscle repair following acute and chronic muscle injuries. Here, we will review briefly the mechanisms and functions of nitric oxide in skeletal muscle and discuss its role in myogenesis, with specific attention to the promising nitric oxide-based approaches now being explored at the pre-clinical and clinical level for the therapy of muscular dystrophy.
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214
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Mitocans, Mitochondria-Targeting Anticancer Drugs. ACTA ACUST UNITED AC 2012. [DOI: 10.1201/b12308-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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215
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Lin TK, Cheng CH, Chen SD, Liou CW, Huang CR, Chuang YC. Mitochondrial dysfunction and oxidative stress promote apoptotic cell death in the striatum via cytochrome c/caspase-3 signaling cascade following chronic rotenone intoxication in rats. Int J Mol Sci 2012; 13:8722-8739. [PMID: 22942730 PMCID: PMC3430261 DOI: 10.3390/ijms13078722] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 07/04/2012] [Accepted: 07/05/2012] [Indexed: 12/21/2022] Open
Abstract
Parkinson's disease (PD) is a progressive neurological disorder marked by nigrostriatal dopaminergic degeneration. Evidence suggests that mitochondrial dysfunction may be linked to PD through a variety of different pathways, including free-radical generation and dysfunction of the mitochondrial Complex I activity. In Lewis rats, chronic systemic administration of a specific mitochondrial Complex I inhibitor, rotenone (3 mg/kg/day) produced parkinsonism-like symptoms. Increased oxidized proteins and peroxynitrite, and mitochondrial or cytosol translocation of Bim, Bax or cytochrome c in the striatum was observed after 2-4 weeks of rotenone infusion. After 28 days of systemic rotenone exposure, imunohistochemical staining for tyrosine hydroxylase indicated nigrostriatal dopaminergic neuronal cell degeneration. Characteristic histochemical (TUNEL or activated caspase-3 staining) or ultrastructural (electron microscopy) features of apoptotic cell death were present in the striatal neuronal cell after chronic rotenone intoxication. We conclude that chronic rotenone intoxication may enhance oxidative and nitrosative stress that induces mitochondrial dysfunction and ultrastructural damage, resulting in translocation of Bim and Bax from cytosol to mitochondria that contributes to apoptotic cell death in the striatum via cytochrome c/caspase-3 signaling cascade.
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Affiliation(s)
- Tsu-Kung Lin
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan; E-Mails: (S.-D.C.); (C.-W.L.); (C.-R.H.)
- Center for Parkinson’s Disease, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan
- Authors to whom correspondence should be addressed; E-Mails: (T.-K.L.); (Y.-C.C.); Tel.: +886-7-7317123 (T.-K.L.) (Y.-C.C.); Fax: +886-7-7318762 (T.-K.L.) (Y.-C.C.)
| | - Ching-Hsiao Cheng
- Neurosurgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan; E-Mail:
| | - Shang-Der Chen
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan; E-Mails: (S.-D.C.); (C.-W.L.); (C.-R.H.)
- Center for Parkinson’s Disease, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan
| | - Chia-Wei Liou
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan; E-Mails: (S.-D.C.); (C.-W.L.); (C.-R.H.)
- Center for Parkinson’s Disease, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan
| | - Chi-Ren Huang
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan; E-Mails: (S.-D.C.); (C.-W.L.); (C.-R.H.)
| | - Yao-Chung Chuang
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan; E-Mails: (S.-D.C.); (C.-W.L.); (C.-R.H.)
- Center for Parkinson’s Disease, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan
- Neurosurgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833, Taiwan; E-Mail:
- Department of Biological Science, National Sun Yet-Sen University, Kaohsiung 804, Taiwan
- Authors to whom correspondence should be addressed; E-Mails: (T.-K.L.); (Y.-C.C.); Tel.: +886-7-7317123 (T.-K.L.) (Y.-C.C.); Fax: +886-7-7318762 (T.-K.L.) (Y.-C.C.)
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216
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Wiseman DA, Thurmond DC. The good and bad effects of cysteine S-nitrosylation and tyrosine nitration upon insulin exocytosis: a balancing act. Curr Diabetes Rev 2012; 8:303-15. [PMID: 22587517 PMCID: PMC3571098 DOI: 10.2174/157339912800840514] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 03/28/2012] [Accepted: 04/14/2012] [Indexed: 12/21/2022]
Abstract
As understanding of the mechanisms driving and regulating insulin secretion from pancreatic beta cells grows, there is increasing and compelling evidence that nitric oxide (•NO) and other closely-related reactive nitrogen species (RNS) play important roles in this exocytic process. •NO and associated RNS, in particular peroxynitrite, possess the capability to effect signals across both intracellular and extracellular compartments in rapid fashion, affording extraordinary signaling potential. It is well established that nitric oxide signals through activation of guanylate cyclase-mediated production of cyclic GMP. The intricate intracellular redox environment, however, lends credence to the possibility that •NO and peroxynitrite could interact with a wider variety of biological targets, with two leading mechanisms involving 1) Snitrosylation of cysteine, and 2) nitration of tyrosine residues comprised within a variety of proteins. Efforts aimed at delineating the specific roles of •NO and peroxynitrite in regulated insulin secretion indicate that a highly-complex and nuanced system exists, with evidence that •NO and peroxynitrite can contribute in both positive and negative regulatory ways in beta cells. Furthermore, the ultimate biochemical outcome within beta cells, whether to compensate and recover from a given stress, or not, is likely a summation of contributory signals and redox status. Such seeming regulatory dichotomy provides ample opportunity for these mechanisms to serve both physiological and pathophysiologic roles in onset and progression of diabetes. This review focuses attention upon recent accumulating evidence pointing to roles for nitric oxide induced post-translational modifications in the normal regulation as well as the dysfunction of beta cell insulin exocytosis.
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Affiliation(s)
- Dean A. Wiseman
- Department of Pediatrics, Herman B Wells Center, Basic Diabetes Group, Indian University School of Medicine, Indianapolis, IN 46202
- Address correspondence to this author at the 635 Barnhill Drive, MS 2031, Indianapolis IN 46202, USA; Tel: 317-274-1551; Fax: 317-274-4107: and
| | - Debbie C. Thurmond
- Department of Pediatrics, Herman B Wells Center, Basic Diabetes Group, Indian University School of Medicine, Indianapolis, IN 46202
- Department of Biochemistry and Molecular Biology, Indian University School of Medicine, Indianapolis, IN 46202
- Department of Cellular and Integrative Physiology, Indian University School of Medicine, Indianapolis, IN 46202
- Address correspondence to this author at the 635 Barnhill Drive, MS 2031, Indianapolis IN 46202, USA; Tel: 317-274-1551; Fax: 317-274-4107: and
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Groschner LN, Waldeck-Weiermair M, Malli R, Graier WF. Endothelial mitochondria--less respiration, more integration. Pflugers Arch 2012; 464:63-76. [PMID: 22382745 PMCID: PMC3387498 DOI: 10.1007/s00424-012-1085-z] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 02/11/2012] [Indexed: 12/21/2022]
Abstract
Lining the inner surface of the circulatory system, the vascular endothelium accomplishes a vast variety of specialized functions. Even slight alterations of these functions are implicated in the development of certain cardiovascular diseases that represent major causes of morbidity and mortality in developed countries. Endothelial mitochondria are essential to the functional integrity of the endothelial cell as they integrate a wide range of cellular processes including Ca²⁺ handling, redox signaling and apoptosis, all of which are closely interrelated. Growing evidence supports the notion that impairment of mitochondrial signaling in the endothelium is an early event and a causative factor in the development of diseases such as atherosclerosis or diabetic complications. In this review, we want to outline the significance of mitochondria in both physiology and pathology of the vascular endothelium.
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Affiliation(s)
- Lukas N. Groschner
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21/III, 8010 Graz, Austria
| | - Markus Waldeck-Weiermair
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21/III, 8010 Graz, Austria
| | - Roland Malli
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21/III, 8010 Graz, Austria
| | - Wolfgang F. Graier
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Harrachgasse 21/III, 8010 Graz, Austria
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218
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The Chemical Interplay between Nitric Oxide and Mitochondrial Cytochrome c Oxidase: Reactions, Effectors and Pathophysiology. Int J Cell Biol 2012; 2012:571067. [PMID: 22811713 PMCID: PMC3395247 DOI: 10.1155/2012/571067] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Accepted: 03/23/2012] [Indexed: 01/20/2023] Open
Abstract
Nitric oxide (NO) reacts with Complex I and cytochrome c oxidase (CcOX, Complex IV), inducing detrimental or cytoprotective effects. Two alternative reaction pathways (PWs) have been described whereby NO reacts with CcOX, producing either a relatively labile nitrite-bound derivative (CcOX-NO2
−, PW1) or a more stable nitrosyl-derivative (CcOX-NO, PW2). The two derivatives are both inhibited, displaying different persistency and O2 competitiveness. In the mitochondrion, during turnover with O2, one pathway prevails over the other one depending on NO, cytochrome c2+ and O2 concentration. High cytochrome c2+, and low O2 proved to be crucial in favoring CcOX nitrosylation, whereas under-standard cell-culture conditions formation of the nitrite derivative prevails. All together, these findings suggest that NO can modulate physiologically the mitochondrial respiratory/OXPHOS efficiency, eventually being converted to nitrite by CcOX, without cell detrimental effects. It is worthy to point out that nitrite, far from being a simple oxidation byproduct, represents a source of NO particularly important in view of the NO cell homeostasis, the NO production depends on the NO synthases whose activity is controlled by different stimuli/effectors; relevant to its bioavailability, NO is also produced by recycling cell/body nitrite. Bioenergetic parameters, such as mitochondrial ΔΨ, lactate, and ATP production, have been assayed in several cell lines, in the presence of endogenous or exogenous NO and the evidence collected suggests a crucial interplay between CcOX and NO with important energetic implications.
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219
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Nitric oxide inactivation mechanisms in the brain: role in bioenergetics and neurodegeneration. Int J Cell Biol 2012; 2012:391914. [PMID: 22719764 PMCID: PMC3376480 DOI: 10.1155/2012/391914] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Accepted: 04/18/2012] [Indexed: 10/28/2022] Open
Abstract
During the last decades nitric oxide ((•)NO) has emerged as a critical physiological signaling molecule in mammalian tissues, notably in the brain. (•)NO may modify the activity of regulatory proteins via direct reaction with the heme moiety, or indirectly, via S-nitrosylation of thiol groups or nitration of tyrosine residues. However, a conceptual understanding of how (•)NO bioactivity is carried out in biological systems is hampered by the lack of knowledge on its dynamics in vivo. Key questions still lacking concrete and definitive answers include those related with quantitative issues of its concentration dynamics and diffusion, summarized in the how much, how long, and how far trilogy. For instance, a major problem is the lack of knowledge of what constitutes a physiological (•)NO concentration and what constitutes a pathological one and how is (•)NO concentration regulated. The ambient (•)NO concentration reflects the balance between the rate of synthesis and the rate of breakdown. Much has been learnt about the mechanism of (•)NO synthesis, but the inactivation pathways of (•)NO has been almost completely ignored. We have recently addressed these issues in vivo on basis of microelectrode technology that allows a fine-tuned spatial and temporal measurement (•)NO concentration dynamics in the brain.
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220
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Yu Z, Liu N, Liu J, Yang K, Wang X. Neuroglobin, a novel target for endogenous neuroprotection against stroke and neurodegenerative disorders. Int J Mol Sci 2012; 13:6995-7014. [PMID: 22837676 PMCID: PMC3397508 DOI: 10.3390/ijms13066995] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2012] [Revised: 05/25/2012] [Accepted: 05/31/2012] [Indexed: 11/16/2022] Open
Abstract
Brain neurons and tissues respond to sublethal injury by activating endogenous protective pathways. Recently, following the failure of a large number of clinical trials for protective strategies against stroke that aim to inhibit a specific ischemia response pathway, endogenous neuroprotection has emerged as a more promising and hopeful strategy for development of therapeutics against stroke and neurodegenerative disorders. Neuroglobin (Ngb) is an oxygen-binding globin protein that is highly and specifically expressed in brain neurons. Accumulating evidence have clearly demonstrated that Ngb is an endogenous neuroprotective molecule against hypoxic/ischemic and oxidative stress-related insults in cultured neurons and animals, as well as neurodegenerative disorders such as Alzheimer’s disease, thus any pharmacological strategy that can up-regulate endogenous Ngb expression may lead to novel therapeutics against these brain disorders. In this review, we summarize recent studies about the biological function, regulation of gene expression, and neuroprotective mechanisms of Ngb. Furthermore, strategies for identification of chemical compounds that can up-regulate endogenous Ngb expression for neuroprotection against stroke and neurodegenerative disorders are discussed.
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Affiliation(s)
- Zhanyang Yu
- Neuroprotection Research Laboratory, Department of Neurology and Radiology, Massachusetts General Hospital, Neuroscience Program, Harvard Medical School, Room 2401/2411A, 149 13th Street, Charlestown Boston, MA 02129, USA; E-Mails: (N.L.); (K.Y.)
- Authors to whom correspondence should be addressed; E-Mails: (Z.Y.); (X.W.); Tel.: +1-617-724-9503 (Z.Y.); +1-617-724-9513 (X.W.); Fax: +1-617-726-7830 (Z.Y.); +1-617-726-7830 (X.W.)
| | - Ning Liu
- Neuroprotection Research Laboratory, Department of Neurology and Radiology, Massachusetts General Hospital, Neuroscience Program, Harvard Medical School, Room 2401/2411A, 149 13th Street, Charlestown Boston, MA 02129, USA; E-Mails: (N.L.); (K.Y.)
| | - Jianxiang Liu
- National Institute for Radiological Protection, China Center for Disease Control and Prevention, Beijing 100088, China; E-Mail:
| | - Kevin Yang
- Neuroprotection Research Laboratory, Department of Neurology and Radiology, Massachusetts General Hospital, Neuroscience Program, Harvard Medical School, Room 2401/2411A, 149 13th Street, Charlestown Boston, MA 02129, USA; E-Mails: (N.L.); (K.Y.)
| | - Xiaoying Wang
- Neuroprotection Research Laboratory, Department of Neurology and Radiology, Massachusetts General Hospital, Neuroscience Program, Harvard Medical School, Room 2401/2411A, 149 13th Street, Charlestown Boston, MA 02129, USA; E-Mails: (N.L.); (K.Y.)
- Authors to whom correspondence should be addressed; E-Mails: (Z.Y.); (X.W.); Tel.: +1-617-724-9503 (Z.Y.); +1-617-724-9513 (X.W.); Fax: +1-617-726-7830 (Z.Y.); +1-617-726-7830 (X.W.)
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221
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Chen Z, Li Q, Sun Q, Chen H, Wang X, Li N, Yin M, Xie Y, Li H, Tang B. Simultaneous Determination of Reactive Oxygen and Nitrogen Species in Mitochondrial Compartments of Apoptotic HepG2 Cells and PC12 Cells Based On Microchip Electrophoresis–Laser-Induced Fluorescence. Anal Chem 2012; 84:4687-94. [DOI: 10.1021/ac300255n] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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222
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Nagai N, Ito Y. Dysfunction in cytochrome c oxidase caused by excessive nitric oxide in human lens epithelial cells stimulated with interferon-γ and lipopolysaccharide. Curr Eye Res 2012; 37:889-97. [PMID: 22632269 DOI: 10.3109/02713683.2012.689070] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE We previously found two mechanisms for the dysfunction in Ca(2+) regulation caused by excessive nitric oxide (NO) using the lenses of hereditary cataract model rats: the first is that NO causes a decrease in Adenosine-5'-triphosphate (ATP) level via cytochrome c oxidase (CCO), resulting in a decrease in ATPase function; the second is that NO causes enhanced lipid peroxidation, resulting in the oxidative inhibition of Ca(2+)-ATPase. In this study, we demonstrate the effect of excessive NO on lipid peroxidation and ATP production in human lens using a human lens epithelial cell line, SRA 01/04 (human lens epithelial (HLE) cells). METHODS Excessive NO via inducible NO synthase (iNOS) was induced by stimulating cells with a combination of interferon-gamma (1000 IU IFN-γ) and lipopolysaccharide (100 ng/mL LPS). CCO activity was measured using a Mitochondrial Isolation kit and Cytochrome c Oxidase Assay kit, and ATP levels were determined using a Sigma ATP Bioluminescent Assay Kit and a luminometer AB-2200. RESULTS Cytochrome c oxidase activity and ATP levels were decreased in HLE cells stimulated with IFN-γ and LPS, and aminoguanidine (AG) and diethyldithiocarbamate (DDC) added 6 h before cell collection significantly attenuated these decreases in cells stimulated with the IFN-γ and LPS for 24-30 h. However, the lower CCO activity and ATP levels in HLE cells stimulated with the IFN-γ and LPS for 30 h were not changed by treatment with AG or DDC for 6-12 h, while the CCO activity and ATP levels in HLE cells treated with AG or DDC for 18 were recovered. CONCLUSION Excessive NO causes a decrease in CCO activity and ATP levels, and the recovery time for CCO activity is related to exposure time to NO in HLE cells.
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Affiliation(s)
- Noriaki Nagai
- School of Pharmacy and Pharmaceutical Research and Technology Institute, Kinki University, Higashi-Osaka, Osaka, Japan
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223
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Kamga C, Krishnamurthy S, Shiva S. Myoglobin and mitochondria: a relationship bound by oxygen and nitric oxide. Nitric Oxide 2012; 26:251-8. [PMID: 22465476 DOI: 10.1016/j.niox.2012.03.005] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 03/22/2012] [Indexed: 01/04/2023]
Abstract
Since their initial discovery over a century ago, our knowledge of the functions of myoglobin and the mitochondrion has gradually evolved. The mitochondrion, once thought to be solely responsible for energy production, is now known to be an integral redox and apoptotic signal transducer within the cell. Likewise, myoglobin, traditionally thought of only as an oxygen store, has emerged as a physiological catalyst that can modulate reactive oxygen species levels, facilitate oxygen diffusion and scavenge or generate nitric oxide (NO) depending on oxygen tensions within the cell. By virtue of its unique ability to regulate O(2) and NO levels within the cell, myoglobin can modulate mitochondrial function in energy-demanding tissues such as the beating heart and exercising muscle. In this review, we present the conventional functions of myoglobin and mitochondria, and describe how these roles have been reassessed and advanced, particularly in the context of NO and nitrite signaling. We present the mechanisms by which mitochondria and myoglobin regulate one another within the cell through their interactions with NO and oxygen and discuss the implications of these interactions in terms of health and disease.
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Affiliation(s)
- Christelle Kamga
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA 15261, United States
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224
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Murphy MP. Mitochondrial thiols in antioxidant protection and redox signaling: distinct roles for glutathionylation and other thiol modifications. Antioxid Redox Signal 2012; 16:476-95. [PMID: 21954972 DOI: 10.1089/ars.2011.4289] [Citation(s) in RCA: 251] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
SIGNIFICANCE The mitochondrial matrix contains much of the machinery at the heart of metabolism. This compartment is also exposed to a high and continual flux of superoxide, hydrogen peroxide, and related reactive species. To protect mitochondria from these sources of oxidative damage, there is an integrated set of thiol systems within the matrix comprising the thioredoxin/peroxiredoxin/methionine sulfoxide reductase pathways and the glutathione/glutathione peroxidase/glutathione-S-transferase/glutaredoxin pathways that in conjunction with protein thiols prevent much of this oxidative damage. In addition, the changes in the redox state of many components of these mitochondrial thiol systems may transduce and relay redox signals within and through the mitochondrial matrix to modulate the activity of biochemical processes. RECENT ADVANCES Here, mitochondrial thiol systems are reviewed, and areas of uncertainty are pointed out, focusing on recent developments in our understanding of their roles. CRITICAL ISSUES The areas of particular focus are on the multiple, overlapping roles of mitochondrial thiols and on understanding how these thiols contribute to both antioxidant defenses and redox signaling. FUTURE DIRECTIONS Recent technical progress in the identification and quantification of thiol modifications by redox proteomics means that many of the questions raised about the multiple roles of mitochondrial thiols can now be addressed.
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225
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Kietadisorn R, Juni RP, Moens AL. Tackling endothelial dysfunction by modulating NOS uncoupling: new insights into its pathogenesis and therapeutic possibilities. Am J Physiol Endocrinol Metab 2012; 302:E481-95. [PMID: 22167522 DOI: 10.1152/ajpendo.00540.2011] [Citation(s) in RCA: 154] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Endothelial nitric oxide synthase (eNOS) serves as a critical enzyme in maintaining vascular pressure by producing nitric oxide (NO); hence, it has a crucial role in the regulation of endothelial function. The bioavailability of eNOS-derived NO is crucial for this function and might be affected at multiple levels. Uncoupling of eNOS, with subsequently less NO and more superoxide generation, is one of the major underlying causes of endothelial dysfunction found in atherosclerosis, diabetes, hypertension, cigarette smoking, hyperhomocysteinemia, and ischemia/reperfusion injury. Therefore, modulating eNOS uncoupling by stabilizing eNOS activity, enhancing its substrate, cofactors, and transcription, and reversing uncoupled eNOS are attractive therapeutic approaches to improve endothelial function. This review provides an extensive overview of the important role of eNOS uncoupling in the pathogenesis of endothelial dysfunction and the potential therapeutic interventions to modulate eNOS for tackling endothelial dysfunction.
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Affiliation(s)
- Rinrada Kietadisorn
- Maastricht Univ. Medical Centre, Cardiovascular Research Institute Maastricht, Maastricht, The Netherlands
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226
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Calcium influx blocked by SK&F 96365 modulates the LPS plus IFN-γ-induced inflammatory response in murine peritoneal macrophages. Int Immunopharmacol 2012; 12:384-93. [DOI: 10.1016/j.intimp.2011.12.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 11/25/2011] [Accepted: 12/15/2011] [Indexed: 11/19/2022]
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Integrating nitric oxide, nitrite and hydrogen sulfide signaling in the physiological adaptations to hypoxia: A comparative approach. Comp Biochem Physiol A Mol Integr Physiol 2012; 162:1-6. [PMID: 22314020 DOI: 10.1016/j.cbpa.2012.01.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 01/18/2012] [Accepted: 01/23/2012] [Indexed: 02/07/2023]
Abstract
Hydrogen sulfide (H(2)S), nitric oxide (NO) and nitrite (NO(2)(-)) are formed in vivo and are of crucial importance in the tissue response to hypoxia, particularly in the cardiovascular system, where these signaling molecules are involved in a multitude of processes including the regulation of vascular tone, cellular metabolic function and cytoprotection. This report summarizes current advances on the mechanisms by which these signaling pathways act and may have evolved in animals with different tolerance to hypoxia, as presented and discussed during the scientific sessions of the annual meeting of the Society for Experimental Biology in 2011 in Glasgow. It also highlights the need and potential for a comparative approach of study and collaborative effort to identify potential link(s) between the signaling pathways involving NO, nitrite and H(2)S in the whole-body responses to hypoxia.
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228
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Ischemia-induced inhibition of mitochondrial complex I in rat brain: effect of permeabilization method and electron acceptor. Neurochem Res 2012; 37:965-76. [PMID: 22219133 DOI: 10.1007/s11064-011-0689-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 12/18/2011] [Accepted: 12/23/2011] [Indexed: 12/23/2022]
Abstract
In this study we have examined the effect of global brain ischemia/reperfusion on biochemical properties of the mitochondrial respiratory complex I (CI) in rat hippocampus and cortex. Since the inner mitochondrial membrane forms the permeability barrier for NADH, the methodology of enzymatic activity determinations employs membrane permeabilization methods. This action affects the basic character of electrostatic and hydrophobic interactions inside the membrane and might influence functional properties of membrane embedded proteins. Therefore we have performed the comparative analysis of two permeabilization methods (sonication, detergent) and their impact on CI enzymatic activities under global brain ischemic-reperfusion conditions. We have observed that ischemia led to significant decrease of CI activities using both permeabilization methods in both brain areas. However, significant differencies in enzymatic activities were registered during reperfusion intervals according to used permeabilization method. We have also tested the effect of electron acceptors (decylubiquinone, potassium ferricyanide, nitrotetrazolium blue) on CI activities during I/R. Based on our results we assume that the critical site where ischemia affects CI activities is electron transfer to electron acceptor. Further, the observed mitochondrial dysfunction was analyzed by means of one and 2-dimensional BN PAGE/SDS PAGE with the focus on 3-nitrotyrosine immunodetection as a marker of oxidative damage to proteins. Add to this, initialization of p53 mitochondrial apoptosis through p53, Bax, Bcl-X(L) proteins and a possible involvement of GRIM-19, the CI structural subunit, in apoptotic processes were also studied.
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229
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Scatena R. Mitochondria and cancer: a growing role in apoptosis, cancer cell metabolism and dedifferentiation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 942:287-308. [PMID: 22399428 DOI: 10.1007/978-94-007-2869-1_13] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
At the beginning of the twentieth century, Otto Warburg demonstrated that cancer cells have a peculiar metabolism. These cells preferentially utilise glycolysis for energetic and anabolic purposes, producing large quantities of lactic acid. He defined this unusual metabolism "aerobic glycolysis". At the same time, Warburg hypothesised that a disruption of mitochondrial activities played a precise pathogenic role in cancer. Because of this so-called "Warburg effect", mitochondrial physiology and cellular respiration in particular have been overlooked in pathophysiological studies of cancer. Over time, however, many studies have shown that mitochondria play a fundamental role in cell death by apoptosis or necrosis. Moreover, metabolic enzymes of the Krebs cycle have also recently been recognised as oncosuppressors. Recently, a series of studies were undertaken to re-evaluate the role of oxidative mitochondrial metabolism in cancer cell growth and progression. Some of these data indicate that modulation of mitochondrial respiration may induce an arrest of cancer cell proliferation and differentiation (pseudodifferentiation) and/or or death, suggesting that iatrogenic manipulation of some mitochondrial activities may induce anticancer effects. Moreover, studying the role of mitochondria in cancer cell dedifferentiation/differentiation processes may allow further insight into the pathophysiology and therapy of so-called cancer stem cells.
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Affiliation(s)
- Roberto Scatena
- Department of Laboratory Medicine, Catholic University, Rome, Italy.
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230
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Sarti P, Arese M, Forte E, Giuffrè A, Mastronicola D. Mitochondria and nitric oxide: chemistry and pathophysiology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 942:75-92. [PMID: 22399419 DOI: 10.1007/978-94-007-2869-1_4] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cell respiration is controlled by nitric oxide (NO) reacting with respiratory chain complexes, particularly with Complex I and IV. The functional implication of these reactions is different owing to involvement of different mechanisms. Inhibition of complex IV is rapid (milliseconds) and reversible, and occurs at nanomolar NO concentrations, whereas inhibition of complex I occurs after a prolonged exposure to higher NO concentrations. The inhibition of Complex I involves the reversible S-nitrosation of a key cysteine residue on the ND3 subunit. The reaction of NO with cytochrome c oxidase (CcOX) directly involves the active site of the enzyme: two mechanisms have been described leading to formation of either a relatively stable nitrosyl-derivative (CcOX-NO) or a more labile nitrite-derivative (CcOX-NO (2) (-) ). Both adducts are inhibited, though with different K(I); one mechanism prevails on the other depending on the turnover conditions and availability of substrates, cytochrome c and O(2). SH-SY5Y neuroblastoma cells or lymphoid cells, cultured under standard O(2) tension, proved to follow the mechanism leading to degradation of NO to nitrite. Formation of CcOX-NO occurred upon rising the electron flux level at this site, artificially or in the presence of higher amounts of endogenous reduced cytochrome c. Taken together, the observations suggest that the expression level of mitochondrial cytochrome c may be crucial to determine the respiratory chain NO inhibition pathway prevailing in vivo under nitrosative stress conditions. The putative patho-physiological relevance of the interaction between NO and the respiratory complexes is addressed.
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Affiliation(s)
- Paolo Sarti
- Department of Biochemical Sciences, University of Rome, Rome, Italy.
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231
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Neuroglobin: A Novel Target for Endogenous Neuroprotection. Transl Stroke Res 2012. [DOI: 10.1007/978-1-4419-9530-8_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
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232
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Cattaneo MG, Cappellini E, Benfante R, Ragni M, Omodeo-Salè F, Nisoli E, Borgese N, Vicentini LM. Chronic deficiency of nitric oxide affects hypoxia inducible factor-1α (HIF-1α) stability and migration in human endothelial cells. PLoS One 2011; 6:e29680. [PMID: 22216344 PMCID: PMC3246476 DOI: 10.1371/journal.pone.0029680] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Accepted: 12/01/2011] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Endothelial dysfunction in widely diffuse disorders, such as atherosclerosis, hypertension, diabetes and senescence, is associated with nitric oxide (NO) deficiency. Here, the behavioural and molecular consequences deriving from NO deficiency in human umbilical vein endothelial cells (HUVECs) were investigated. RESULTS Endothelial nitric oxide synthase (eNOS) was chronically inhibited either by N(G)-Nitro-L-arginine methyl ester (L-NAME) treatment or its expression was down-regulated by RNA interference. After long-term L-NAME treatment, HUVECs displayed a higher migratory capability accompanied by an increased Vascular Endothelial Growth Factor (VEGF) and VEGF receptor-2 (kinase insert domain receptor, KDR) expression. Moreover, both pharmacological and genetic inhibition of eNOS induced a state of pseudohypoxia, revealed by the stabilization of hypoxia-inducible factor-1α (HIF-1α). Furthermore, NO loss induced a significant decrease in mitochondrial mass and energy production accompanied by a lower O(2) consumption. Notably, very low doses of chronically administered DETA/NO reverted the HIF-1α accumulation, the increased VEGF expression and the stimulated migratory behaviour detected in NO deficient cells. CONCLUSION Based on our results, we propose that basal release of NO may act as a negative controller of HIF-1α levels with important consequences for endothelial cell physiology. Moreover, we suggest that our experimental model where eNOS activity was impaired by pharmacological and genetic inhibition may represent a good in vitro system to study endothelial dysfunction.
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Affiliation(s)
- Maria Grazia Cattaneo
- Department of Pharmacology, School of Medicine, Università degli Studi di Milano, Milano, Italy
| | - Elisa Cappellini
- Department of Pharmacology, School of Medicine, Università degli Studi di Milano, Milano, Italy
| | - Roberta Benfante
- Department of Pharmacology, School of Medicine, Università degli Studi di Milano, Milano, Italy
- CNR, Institute of Neuroscience, Milano, Italy
| | - Maurizio Ragni
- Department of Pharmacology, School of Medicine, Università degli Studi di Milano, Milano, Italy
| | - Fausta Omodeo-Salè
- Department of Molecular Sciences Applied to Biosystems, Faculty of Pharmacy, Università degli Studi di Milano, Milano, Italy
| | - Enzo Nisoli
- Department of Pharmacology, School of Medicine, Università degli Studi di Milano, Milano, Italy
| | - Nica Borgese
- Department of Pharmacology, School of Medicine, Università degli Studi di Milano, Milano, Italy
- CNR, Institute of Neuroscience, Milano, Italy
- Department of Pharmacobiological Science, University of Catanzaro “Magna Graecia”, Roccelletta di Borgia (Cz), Italy
| | - Lucia M. Vicentini
- Department of Pharmacology, School of Medicine, Università degli Studi di Milano, Milano, Italy
- * E-mail:
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Rohlena J, Dong LF, Ralph SJ, Neuzil J. Anticancer drugs targeting the mitochondrial electron transport chain. Antioxid Redox Signal 2011; 15:2951-74. [PMID: 21777145 DOI: 10.1089/ars.2011.3990] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
SIGNIFICANCE Mitochondria are emerging as highly intriguing organelles showing promise but that are yet to be fully exploited as targets for anticancer drugs. RECENT ADVANCES A group of compounds that induce mitochondrial destabilization, thereby affecting the physiology of cancer cells, has been defined and termed 'mitocans.' Based on their mode of action of targeting in and around mitochondria, we have placed these agents into several groups including hexokinase inhibitors, compounds targeting Bcl-2 family proteins, thiol redox inhibitors, VDAC/ANT targeting drugs, electron transport chain-targeting drugs, lipophilic cations targeting the inner membrane, agents affecting the tricarboxylic acid cycle, drugs targeting mtDNA, and agents targeting other presently unknown sites. CRITICAL ISSUES Mitocans have a potential to prove highly efficient in suppressing various malignant diseases in a selective manner. They include compounds that are currently in clinical trial and offer substantial promise to become clinically applied drugs. Here we update and redefine the individual classes of mitocans, providing examples of the various members of these groups with a particular focus on agents targeting the electron transport chain, and indicate their potential application in clinical practice. FUTURE DIRECTIONS Even though reactive oxygen species induction is important for the anticancer activity of many mitocans, the precise sequence of events preceding and following this pivotal event are not yet fully clarified, and warrant further investigation. This is imperative for effective deployment of these compounds in the clinic.
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Affiliation(s)
- Jakub Rohlena
- Institute of Biotechnology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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235
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Seimetz M, Parajuli N, Pichl A, Veit F, Kwapiszewska G, Weisel FC, Milger K, Egemnazarov B, Turowska A, Fuchs B, Nikam S, Roth M, Sydykov A, Medebach T, Klepetko W, Jaksch P, Dumitrascu R, Garn H, Voswinckel R, Kostin S, Seeger W, Schermuly RT, Grimminger F, Ghofrani HA, Weissmann N. Inducible NOS inhibition reverses tobacco-smoke-induced emphysema and pulmonary hypertension in mice. Cell 2011; 147:293-305. [PMID: 22000010 DOI: 10.1016/j.cell.2011.08.035] [Citation(s) in RCA: 248] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Revised: 04/30/2011] [Accepted: 08/13/2011] [Indexed: 12/12/2022]
Abstract
Chronic obstructive pulmonary disease (COPD) is one of the most common causes of death worldwide. We report in an emphysema model of mice chronically exposed to tobacco smoke that pulmonary vascular dysfunction, vascular remodeling, and pulmonary hypertension (PH) precede development of alveolar destruction. We provide evidence for a causative role of inducible nitric oxide synthase (iNOS) and peroxynitrite in this context. Mice lacking iNOS were protected against emphysema and PH. Treatment of wild-type mice with the iNOS inhibitor N(6)-(1-iminoethyl)-L-lysine (L-NIL) prevented structural and functional alterations of both the lung vasculature and alveoli and also reversed established disease. In chimeric mice lacking iNOS in bone marrow (BM)-derived cells, PH was dependent on iNOS from BM-derived cells, whereas emphysema development was dependent on iNOS from non-BM-derived cells. Similar regulatory and structural alterations as seen in mouse lungs were found in lung tissue from humans with end-stage COPD.
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Affiliation(s)
- Michael Seimetz
- University of Giessen Lung Center, Excellence Cluster Cardiopulmonary System, Giessen, Germany
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236
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Gibbs PEM, Miralem T, Lerner-Marmarosh N, Tudor C, Maines MD. Formation of ternary complex of human biliverdin reductase-protein kinase Cδ-ERK2 protein is essential for ERK2-mediated activation of Elk1 protein, nuclear factor-κB, and inducible nitric-oxidase synthase (iNOS). J Biol Chem 2011; 287:1066-79. [PMID: 22065579 DOI: 10.1074/jbc.m111.279612] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Growth factors, insulin, oxidative stress, and cytokines activate ERK1/2 by PKCδ and MEK1/2. Human biliverdin reductase (hBVR), a Ser/Thr/Tyr kinase and intracellular scaffold/bridge/anchor, is a nuclear transporter of MEK1/2-stimulated ERK1/2 (Lerner-Marmarosh, N., Miralem, T., Gibbs, P. E., and Maines, M. D. (2008) Proc. Natl. Acad. Sci. U.S.A. 105, 6870-6875). hBVR, PKCδ, and MEK1/2 overlap in their tissue expression profile and type of activators. Presently, we report on formation of an hBVR-PKCδ-ERK2 ternary complex that is essential for ERK2 signal transduction and activation of genes linked to cell proliferation and cancer. MEK1/2 and the protein phosphatase PP2A were also present in the complex. When cells were stimulated with insulin-like growth factor-1 (IGF-1), an increased interaction between hBVR and PKCδ was detected by FRET-fluorescence lifetime imaging microscopy. hBVR and ERK2 were phosphorylated by PKCδ; however, the PKC was not a substrate for either ERK2 or hBVR. IGF-1 and phorbol ester increased hBVR/PKCδ binding; hBVR was required for the activation of PKCδ and its interaction with ERK2. The C-terminal phenylalanine residues of PKCδ (Phe(660), Phe(663), and Phe(665)) were necessary for binding to ERK2 but not for hBVR binding. Formation of the hBVR-PKCδ-ERK2 complex required the hBVR docking site for ERK, FXFP (DEF, C-box) and D(δ)-box (ILXXLXL) motifs. The hBVR-based peptide KKRILHCLGLA inhibited PKC activation and PKCδ/ERK2 interaction. Phorbol ester- and TNF-α-dependent activation of the ERK-regulated transcription factors Elk1 and NF-κB and expression of the iNOS gene were suppressed by hBVR siRNA; those activities were rescued by hBVR. The findings reveal the direct input of hBVR in PKCδ/ERK signaling and identify hBVR-based peptide regulators of ERK-mediated gene activation.
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Affiliation(s)
- Peter E M Gibbs
- Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642, USA
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237
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Yu Z, Liu N, Wang Y, Li X, Wang X. Identification of neuroglobin-interacting proteins using yeast two-hybrid screening. Neuroscience 2011; 200:99-105. [PMID: 22079573 DOI: 10.1016/j.neuroscience.2011.10.046] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Revised: 10/19/2011] [Accepted: 10/25/2011] [Indexed: 01/27/2023]
Abstract
Neuroglobin (Ngb) is a globin protein that is highly and specifically expressed in brain neurons. A large volume of evidence has proven that Ngb is a neuroprotective molecule against hypoxic/ischemic brain injury and other related neurological disorder; however, the underlying mechanisms remain poorly understood. Aiming to provide more clues in understanding the molecular mechanisms of Ngb's neuroprotection, we performed yeast two-hybrid screening to search for proteins that interact with Ngb. From a mouse brain cDNA library, we found totally 36 proteins that potentially interact with Ngb, and 10 of them were each identified in multiple positive clones. The shared sequences within these multiple clones are more likely to be Ngb-interacting domains. In primary cultured mouse cortical neurons, immuno-precipitation was performed to confirm the interactions of selected proteins with Ngb. The discovered Ngb-interacting proteins in this study include those involved in energy metabolism, mitochondria function, and signaling pathways for cell survival and proliferation. Our findings provide molecular targets for investigating protein interaction-based biological functions and neuroprotective mechanisms of Ngb.
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Affiliation(s)
- Z Yu
- Neuroprotection Research Laboratory, Departments of Neurology and Radiology, Massachusetts General Hospital, and Program in Neuroscience, Harvard Medical School, Charlestown, MA, USA.
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238
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Bråtane BT, Cui H, Cook DJ, Bouley J, Tymianski M, Fisher M. Neuroprotection by Freezing Ischemic Penumbra Evolution Without Cerebral Blood Flow Augmentation With a Postsynaptic Density-95 Protein Inhibitor. Stroke 2011; 42:3265-70. [DOI: 10.1161/strokeaha.111.618801] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background and Purpose—
The purpose of this study was to determine whether neuroprotection is feasible without cerebral blood flow augmentation in experimental permanent middle cerebral artery occlusion.
Methods—
Rats were subjected to permanent middle cerebral artery occlusion by the suture occlusion method and were treated 1 hour thereafter with a single 5-minute intravenous infusion of the postsynaptic density-95 protein inhibitor Tat-NR2B9c (7.5 mg/kg) or saline (n=8/group). Arterial spin-labeled perfusion-weighted MRI and diffusion weighted MRI were obtained with a 4.7-T Bruker system at 30, 45, 70, 90, 120, 150, and 180 minutes postmiddle cerebral artery occlusion to determine cerebral blood flow and apparent diffusion coefficient maps, respectively. At 24 hours, animals were neurologically scored (0 to 5), euthanized, and the brains stained with 2–3-5-triphenyl tetrazolium chloride to ascertain infarct volumes corrected for edema. Additionally, the effects of Tat-NR2B9c on adenosine 5′-triphosphate levels were measured in vitro in neurons subjected to oxygen–glucose deprivation.
Results—
Final infarct volume was decreased by 30.3% in the Tat-NR2B9c-treated animals compared with controls (
P
=0.028). There was a significant improvement in 24 hours neurological scores in the Tat-NR2B9c group compared with controls, 1.8±0.5 and 2.8±1.0, respectively (
P
=0.021). Relative to controls, Tat-NR2B9c significantly attenuated diffusion-weighted imaging lesion growth and preserved the diffusion-weighted imaging/perfusion-weighted imaging mismatch (ischemic penumbra) without affecting cerebral blood flow in the ischemic core or penumbra. Tat-NR2B9c treatment of primary neuronal cultures resulted in 26% increase in cell viability and 34% greater adenosine 5′-triphosphate levels after oxygen–glucose deprivation.
Conclusions—
Preservation of adenosine 5′-triphosphate levels in vitro and neuroprotection in permanent middle cerebral artery occlusion in rats is achievable without cerebral blood flow augmentation using a postsynaptic density-95 protein inhibitor.
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Affiliation(s)
- Bernt T. Bråtane
- From the Department of Neurology (B.T.B., J.B., M.F.), University of Massachusetts Medical School, Worcester, MA; and Toronto Western Research Institute (H.C., D.J.C., M.T.), University Health Network, Toronto, Ontario, Canada
| | - Hong Cui
- From the Department of Neurology (B.T.B., J.B., M.F.), University of Massachusetts Medical School, Worcester, MA; and Toronto Western Research Institute (H.C., D.J.C., M.T.), University Health Network, Toronto, Ontario, Canada
| | - Douglas J. Cook
- From the Department of Neurology (B.T.B., J.B., M.F.), University of Massachusetts Medical School, Worcester, MA; and Toronto Western Research Institute (H.C., D.J.C., M.T.), University Health Network, Toronto, Ontario, Canada
| | - James Bouley
- From the Department of Neurology (B.T.B., J.B., M.F.), University of Massachusetts Medical School, Worcester, MA; and Toronto Western Research Institute (H.C., D.J.C., M.T.), University Health Network, Toronto, Ontario, Canada
| | - Michael Tymianski
- From the Department of Neurology (B.T.B., J.B., M.F.), University of Massachusetts Medical School, Worcester, MA; and Toronto Western Research Institute (H.C., D.J.C., M.T.), University Health Network, Toronto, Ontario, Canada
| | - Marc Fisher
- From the Department of Neurology (B.T.B., J.B., M.F.), University of Massachusetts Medical School, Worcester, MA; and Toronto Western Research Institute (H.C., D.J.C., M.T.), University Health Network, Toronto, Ontario, Canada
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239
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Necroptosis: an emerging form of programmed cell death. Crit Rev Oncol Hematol 2011; 82:249-58. [PMID: 21962882 DOI: 10.1016/j.critrevonc.2011.08.004] [Citation(s) in RCA: 163] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2011] [Revised: 07/17/2011] [Accepted: 08/10/2011] [Indexed: 02/08/2023] Open
Abstract
Necrosis plays an important role in multiple physiological and pathological processes. Recently, a relatively new form of necrosis has been characterized as "necroptosis". Morphologically, necroptosis exhibits the features of necrosis; however, necroptosis exhibits a unique signaling pathway that requires the involvement of receptor interaction protein kinase 1 and 3 (RIP1 and RIP3) and can be specifically inhibited by necrostatins. Necroptosis has been found to contribute to the regulation of immune system, cancer development as well as cellular responses to multiple stresses. In this review, we will summarize the signaling pathway, biological effects and pathological significance of this specific form of programmed cell death.
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240
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Sarti P, Forte E, Mastronicola D, Giuffrè A, Arese M. Cytochrome c oxidase and nitric oxide in action: molecular mechanisms and pathophysiological implications. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1817:610-9. [PMID: 21939634 DOI: 10.1016/j.bbabio.2011.09.002] [Citation(s) in RCA: 340] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 09/06/2011] [Accepted: 09/07/2011] [Indexed: 11/18/2022]
Abstract
BACKGROUND The reactions between Complex IV (cytochrome c oxidase, CcOX) and nitric oxide (NO) were described in the early 60's. The perception, however, that NO could be responsible for physiological or pathological effects, including those on mitochondria, lags behind the 80's, when the identity of the endothelial derived relaxing factor (EDRF) and NO synthesis by the NO synthases were discovered. NO controls mitochondrial respiration, and cytotoxic as well as cytoprotective effects have been described. The depression of OXPHOS ATP synthesis has been observed, attributed to the inhibition of mitochondrial Complex I and IV particularly, found responsible of major effects. SCOPE OF REVIEW The review is focused on CcOX and NO with some hints about pathophysiological implications. The reactions of interest are reviewed, with special attention to the molecular mechanisms underlying the effects of NO observed on cytochrome c oxidase, particularly during turnover with oxygen and reductants. MAJOR CONCLUSIONS AND GENERAL SIGNIFICANCE The NO inhibition of CcOX is rapid and reversible and may occur in competition with oxygen. Inhibition takes place following two pathways leading to formation of either a relatively stable nitrosyl-derivative (CcOX-NO) of the enzyme reduced, or a more labile nitrite-derivative (CcOX-NO(2)(-)) of the enzyme oxidized, and during turnover. The pathway that prevails depends on the turnover conditions and concentration of NO and physiological substrates, cytochrome c and O(2). All evidence suggests that these parameters are crucial in determining the CcOX vs NO reaction pathway prevailing in vivo, with interesting physiological and pathological consequences for cells.
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Affiliation(s)
- Paolo Sarti
- Department of Biochemical Sciences, Sapienza University of Rome, Italy.
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241
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Hydrogen peroxide differentially modulates cardiac myocyte nitric oxide synthesis. Proc Natl Acad Sci U S A 2011; 108:15792-7. [PMID: 21896719 DOI: 10.1073/pnas.1111331108] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Nitric oxide (NO) and hydrogen peroxide (H(2)O(2)) are synthesized within cardiac myocytes and play key roles in modulating cardiovascular signaling. Cardiac myocytes contain both the endothelial (eNOS) and neuronal (nNOS) NO synthases, but the differential roles of these NOS isoforms and the interplay of reactive oxygen species and reactive nitrogen species in cardiac signaling pathways are poorly understood. Using a recently developed NO chemical sensor [Cu(2)(FL2E)] to study adult cardiac myocytes from wild-type, eNOS(null), and nNOS(null) mice, we discovered that physiological concentrations of H(2)O(2) activate eNOS but not nNOS. H(2)O(2)-stimulated eNOS activation depends on phosphorylation of both the AMP-activated protein kinase and kinase Akt, and leads to the robust phosphorylation of eNOS. Cardiac myocytes isolated from mice infected with lentivirus expressing the recently developed H(2)O(2) biosensor HyPer2 show marked H(2)O(2) synthesis when stimulated by angiotensin II, but not following β-adrenergic receptor activation. We discovered that the angiotensin-II-promoted increase in cardiac myocyte contractility is dependent on H(2)O(2), whereas β-adrenergic contractile responses occur independently of H(2)O(2) signaling. These studies establish differential roles for H(2)O(2) in control of cardiac contractility and receptor-dependent NOS activation in the heart, and they identify new points for modulation of NO signaling responses by oxidant stress.
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242
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Osborne NN. WITHDRAWN: Reprint of: Mitochondria: Their role in ganglion cell death and survival in primary open angle glaucoma. Exp Eye Res 2011:S0014-4835(11)00225-9. [PMID: 21819980 DOI: 10.1016/j.exer.2011.07.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Accepted: 03/08/2010] [Indexed: 11/20/2022]
Abstract
The Publisher regrets that this article is an accidental duplication of an article that has already been published, doi:10.1016/j.exer.2010.03.008. The duplicate article has therefore been withdrawn.
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Affiliation(s)
- Neville N Osborne
- Nuffield Laboratory of Ophthalmology, University of Oxford, UK; Instituto Oftalmologico, Fundación de Investigación Optalmologica, Fernandez-Vega, Oviedo, Spain
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243
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Mekahli D, Bultynck G, Parys JB, De Smedt H, Missiaen L. Endoplasmic-reticulum calcium depletion and disease. Cold Spring Harb Perspect Biol 2011; 3:a004317. [PMID: 21441595 PMCID: PMC3098671 DOI: 10.1101/cshperspect.a004317] [Citation(s) in RCA: 321] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The endoplasmic reticulum (ER) as an intracellular Ca(2+) store not only sets up cytosolic Ca(2+) signals, but, among other functions, also assembles and folds newly synthesized proteins. Alterations in ER homeostasis, including severe Ca(2+) depletion, are an upstream event in the pathophysiology of many diseases. On the one hand, insufficient release of activator Ca(2+) may no longer sustain essential cell functions. On the other hand, loss of luminal Ca(2+) causes ER stress and activates an unfolded protein response, which, depending on the duration and severity of the stress, can reestablish normal ER function or lead to cell death. We will review these various diseases by mainly focusing on the mechanisms that cause ER Ca(2+) depletion.
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Affiliation(s)
- Djalila Mekahli
- Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, KU Leuven Campus Gasthuisberg O&N I, Belgium
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244
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Ilkka H, Bengt S, Jukka K, Sipilä HT, Vesa O, Pirjo N, Juhani K, Kari K, Ylva H. Skeletal muscle blood flow and oxygen uptake at rest and during exercise in humans: a pet study with nitric oxide and cyclooxygenase inhibition. Am J Physiol Heart Circ Physiol 2011; 300:H1510-7. [DOI: 10.1152/ajpheart.00996.2010] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The aim of the present study was to determine the effect of nitric oxide and prostanoids on microcirculation and oxygen uptake, specifically in the active skeletal muscle by use of positron emission tomography (PET). Healthy males performed three 5-min bouts of light knee-extensor exercise. Skeletal muscle blood flow and oxygen uptake were measured at rest and during the exercise using PET with H2O15 and 15O2 during: 1) control conditions; 2) nitric oxide synthase (NOS) inhibition by arterial infusion of NG-monomethyl-l-arginine (l-NMMA), and 3) combined NOS and cyclooxygenase (COX) inhibition by arterial infusion of l-NMMA and indomethacin. At rest, inhibition of NOS alone and in combination with indomethacin reduced ( P < 0.05) muscle blood flow. NOS inhibition increased ( P < 0.05) limb oxygen extraction fraction (OEF) more than the reduction in muscle blood flow, resulting in an ∼20% increase ( P < 0.05) in resting muscle oxygen consumption. During exercise, muscle blood flow and oxygen uptake were not altered with NOS inhibition, whereas muscle OEF was increased ( P < 0.05). NOS and COX inhibition reduced ( P < 0.05) blood flow in working quadriceps femoris muscle by 13%, whereas muscle OEF and oxygen uptake were enhanced by 51 and 30%, respectively. In conclusion, by specifically measuring blood flow and oxygen uptake by the use of PET instead of whole limb measurements, the present study shows for the first time in humans that inhibition of NO formation enhances resting muscle oxygen uptake and that combined inhibition of NOS and COX during exercise increases muscle oxygen uptake.
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Affiliation(s)
- Heinonen Ilkka
- Turku PET Center,
- Departments of 2Clinical Physiology and Nuclear Medicine and
| | - Saltin Bengt
- Copenhagen Muscle Research Center, University of Copenhagen, Copenhagen, Denmark
| | - Kemppainen Jukka
- Turku PET Center,
- Departments of 2Clinical Physiology and Nuclear Medicine and
| | | | | | - Nuutila Pirjo
- Turku PET Center,
- Medicine, Turku University Hospital, University of Turku, Turku, Finland; and
| | | | | | - Hellsten Ylva
- Exercise and Sport Sciences, Section of Human Physiology, and
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245
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Regulation of mitochondrial processes by protein S-nitrosylation. Biochim Biophys Acta Gen Subj 2011; 1820:712-21. [PMID: 21397666 DOI: 10.1016/j.bbagen.2011.03.008] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Revised: 02/21/2011] [Accepted: 03/04/2011] [Indexed: 12/24/2022]
Abstract
BACKGROUND Nitric oxide (NO) exerts powerful physiological effects through guanylate cyclase (GC), a non-mitochondrial enzyme, and through the generation of protein cysteinyl-NO (SNO) adducts-a post-translational modification relevant to mitochondrial biology. A small number of SNO proteins, generated by various mechanisms, are characteristically found in mammalian mitochondria and influence the regulation of oxidative phosphorylation and other aspects of mitochondrial function. SCOPE OF REVIEW The principles by which mitochondrial SNO proteins are formed and their actions, independently or collectively with NO binding to heme, iron-sulfur centers, or to glutathione (GSH) are reviewed on a molecular background of SNO-based signal transduction. MAJOR CONCLUSIONS Mitochondrial SNO-proteins have been demonstrated to inhibit Complex I of the electron transport chain, to modulate mitochondrial reactive oxygen species (ROS) production, influence calcium-dependent opening of the mitochondrial permeability transition pore (MPTP), promote selective importation of mitochondrial protein, and stimulate mitochondrial fission. The ease of reversibility and the affirmation of regulated S-nitros(yl)ating and denitros(yl)ating enzymatic reactions support hypotheses that SNO regulates the mitochondrion through redox mechanisms. SNO modification of mitochondrial proteins, whether homeostatic or adaptive (physiological), or pathogenic, is an area of active investigation. GENERAL SIGNIFICANCE Mitochondrial SNO proteins are associated with mainly protective, bur some pathological effects; the former mainly in inflammatory and ischemia/reperfusion syndromes and the latter in neurodegenerative diseases. Experimentally, mitochondrial SNO delivery is also emerging as a potential new area of therapeutics. This article is part of a Special Issue entitled: Regulation of cellular processes by S-nitrosylation.
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246
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Pagliaro P, Moro F, Tullio F, Perrelli MG, Penna C. Cardioprotective pathways during reperfusion: focus on redox signaling and other modalities of cell signaling. Antioxid Redox Signal 2011; 14:833-50. [PMID: 20649460 DOI: 10.1089/ars.2010.3245] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Post-ischemic reperfusion may result in reactive oxygen species (ROS) generation, reduced availability of nitric oxide (NO•), Ca(2+)overload, prolonged opening of mitochondrial permeability transition pore, and other processes contributing to cell death, myocardial infarction, stunning, and arrhythmias. With the discovery of the preconditioning and postconditioning phenomena, reperfusion injury has been appreciated as a reality from which protection is feasible, especially with postconditioning, which is under the control of physicians. Potentially cooperative protective signaling cascades are recruited by both pre- and postconditioning. In these pathways, phosphorylative/dephosphorylative processes are widely represented. However, cardioprotective modalities of signal transduction also include redox signaling by ROS, S-nitrosylation by NO• and derivative, S-sulfhydration by hydrogen sulfide, and O-linked glycosylation with beta-N-acetylglucosamine. All these modalities can interact and regulate an entire pathway, thus influencing each other. For instance, enzymes can be phosphorylated and/or nitrosylated in specific and/or different site(s) with consequent increase or decrease of their specific activity. The cardioprotective signaling pathways are thought to converge on mitochondria, and various mitochondrial proteins have been identified as targets of these post-transitional modifications in both pre- and postconditioning.
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Affiliation(s)
- Pasquale Pagliaro
- Department of Clinical and Biological Sciences, Università di Torino, Regione Gonzole 10, Orbassano, Turin, Italy.
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247
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Nachuraju P, Friedman AJ, Friedman JM, Cabrales P. Exogenous nitric oxide prevents cardiovascular collapse during hemorrhagic shock. Resuscitation 2011; 82:607-13. [PMID: 21342744 DOI: 10.1016/j.resuscitation.2010.12.025] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Revised: 11/15/2010] [Accepted: 12/27/2010] [Indexed: 11/27/2022]
Abstract
This study investigated the systemic and microvascular hemodynamic changes related to increased nitric oxide (NO) availability following significant hemorrhage, made available by administration of NO releasing nanoparticles (NO-nps). Hemodynamic responses to hemorrhagic shock were studied in the hamster window chamber. Acute hemorrhage was induced by arterial controlled bleeding of 50% of blood volume, and the resulting hemodynamic parameters were followed over 90 min. Exogenous NO was administered in the form of NO-nps (5mg/kg suspended in 50 μl saline) 10 min following induced hemorrhage. Control groups received equal dose of NO free nanoparticles (Control-nps) and Vehicle solution. Animals treated with NO-nps partially maintained systemic and microvascular function during hypovolemic shock compared to animals treated with Control-nps or the Vehicle (50 μl saline). The continuous NO released by the NO-nps reverted arteriolar vasoconstriction, partially recovered both functional capillary density and microvascular blood flows. Additionally, NO supplementation post hemorrhage prevented cardiac decompensation, and thereby maintained and stabilized the heart rate. Paradoxically, the peripheral vasodilation induced by the NO-nps did not decrease blood pressure, and combined with NO's effects on vascular resistance, NO-nps promoted intravascular pressure redistribution and blood flow, avoiding tissue ischemia. Therefore, by increasing NO availability with NO-nps during hypovolemic shock, it is possible that cardiac stability and microvascular perfusion can be preserved, ultimately increasing survivability and local tissue viability, and reducing hemorrhagic shock sequelae. The relevance, stability, and efficacy of exogenous NO therapy in the form of NO-nps will potentially facilitate the intended use in battlefield and trauma situations.
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Affiliation(s)
- Parimala Nachuraju
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, NY, United States
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248
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Olson N, van der Vliet A. Interactions between nitric oxide and hypoxia-inducible factor signaling pathways in inflammatory disease. Nitric Oxide 2011; 25:125-37. [PMID: 21199675 DOI: 10.1016/j.niox.2010.12.010] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 12/22/2010] [Accepted: 12/29/2010] [Indexed: 02/06/2023]
Abstract
Induction and activation of nitric oxide (NO) synthases (NOS) and excessive production of NO are common features of almost all diseases associated with infection and acute or chronic inflammation, although the contribution of NO to the pathophysiology of these diseases is highly multifactorial and often still a matter of controversy. Because of its direct impact on tissue oxygenation and cellular oxygen (O(2)) consumption and re-distribution, the ability of NO to regulate various aspects of hypoxia-induced signaling has received widespread attention. Conditions of tissue hypoxia and the activation of hypoxia-inducible factors (HIF) have been implicated in hypoxia or in cancer biology, but are also being increasingly recognized as important features of acute and chronic inflammation. Thus, the activation of HIF transcription factors has been increasingly implicated in inflammatory diseases, and recent studies have indicated its critical importance in regulating phagocyte function, inflammatory mediator production, and regulation of epithelial integrity and repair processes. Finally, HIF also appears to contribute to important features of tissue fibrosis and epithelial-to-mesenchymal transition, processes that are associated with tissue remodeling in various non-malignant chronic inflammatory disorders. In this review, we briefly summarize the current state of knowledge with respect to the general mechanisms involved in HIF regulation and the impact of NO on HIF activation. Secondly, we will summarize the major recent findings demonstrating a role for HIF signaling in infection, inflammation, and tissue repair and remodeling, and will address the involvement of NO. The growing interest in hypoxia-induced signaling and its relation with NO biology is expected to lead to further insights into the complex roles of NO in acute or chronic inflammatory diseases and may point to the importance of HIF signaling as key feature of NO-mediated events during these disorders.
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Affiliation(s)
- Nels Olson
- Department of Pathology, College of Medicine, University of Vermont, Burlington, VT 05405, USA
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249
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Abstract
Ischemia/reperfusion (I/R) injury still represents an important cause of morbidity following hepatic surgery and limits the use of marginal livers in hepatic transplantation. Transient blood flow interruption followed by reperfusion protects tissues against damage induced by subsequent I/R. This process known as ischemic preconditioning (IP) depends upon intrinsic cytoprotective systems whose activation can inhibit the progression of irreversible tissue damage. Compared to other organs, liver IP has additional features as it reduces inflammation and promotes hepatic regeneration. Our present understanding of the molecular mechanisms involved in liver IP is still largely incomplete. Experimental studies have shown that the protective effects of liver IP are triggered by the release of adenosine and nitric oxide and the subsequent activation of signal networks involving protein kinases such as phosphatidylinositol 3-kinase, protein kinase C δ/ε and p38 MAP kinase, and transcription factors such as signal transducer and activator of transcription 3, nuclear factor-κB and hypoxia-inducible factor 1. This article offers an overview of the molecular events underlying the preconditioning effects in the liver and points to the possibility of developing pharmacological approaches aimed at activating the intrinsic protective systems in patients undergoing liver surgery.
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Robin E, Simerabet M, Hassoun SM, Adamczyk S, Tavernier B, Vallet B, Bordet R, Lebuffe G. Postconditioning in focal cerebral ischemia: role of the mitochondrial ATP-dependent potassium channel. Brain Res 2010; 1375:137-46. [PMID: 21182830 DOI: 10.1016/j.brainres.2010.12.054] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 12/14/2010] [Accepted: 12/14/2010] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Ischemic postconditioning (IpostC) has been described in both heart and brain. The first aim of this study was to evaluate the effects of IpostC on brain infarct size and neurological function in the middle cerebral artery occlusion (MCAO) model. The second aim was to determine the involvement of the mitochondrial potassium ATP-dependent channel (mitoK(ATP)) opening and its capacity to improve mitochondrial dysfunction induced by ischemia-reperfusion. METHODS Wistar rats were subjected to 60min MCAO followed by 24-h reperfusion. Postconditioning was performed by 3 cycles of 30-s occlusion-reperfusion at the onset of reperfusion. Three behavioral tests were performed following 24h of reperfusion. Involvement of mitoK(ATP) was determined by the modulation of IpostC effects by 5-hydroxydecanoate (5-HD) and diazoxide. Mitochondrial function after 24h of reperfusion on isolated mitochondria was assessed through mitochondrial oxygen consumption, mitochondrial membrane potential and calcium retention capacity to evaluate impact of IpostC on mitochondrial permeability transition pore (MPTP) opening. RESULTS IpostC resulted in a 40% decrease in infarct size and improved neurological outcome. These effects were lost when IpostC was delayed by 5min. The administration of diazoxide resulted in a 60% in infarct size. The beneficial effects of IpostC and diazoxide were blocked by 5-HD. Furthermore, 5-HD also blocked the inhibition of MPTP opening by IpostC and diazoxide. The hyperpolarization induced by ischemia-reperfusion was corrected by IpostC without any effect on oxidative phosphorylation. CONCLUSION Our results confirm ischemic postconditioning-induced neuroprotection. They also support the involvement of mitoK(ATP) opening and its role in inhibiting the opening of MTPT induced by postconditioning.
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Affiliation(s)
- Emmanuel Robin
- Department of Pharmacology, Lille Medical School, University of Lille 2, Lille, France
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