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Del Dotto V, Musiani F, Baracca A, Solaini G. Variants in Human ATP Synthase Mitochondrial Genes: Biochemical Dysfunctions, Associated Diseases, and Therapies. Int J Mol Sci 2024; 25:2239. [PMID: 38396915 PMCID: PMC10889682 DOI: 10.3390/ijms25042239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 02/06/2024] [Accepted: 02/08/2024] [Indexed: 02/25/2024] Open
Abstract
Mitochondrial ATP synthase (Complex V) catalyzes the last step of oxidative phosphorylation and provides most of the energy (ATP) required by human cells. The mitochondrial genes MT-ATP6 and MT-ATP8 encode two subunits of the multi-subunit Complex V. Since the discovery of the first MT-ATP6 variant in the year 1990 as the cause of Neuropathy, Ataxia, and Retinitis Pigmentosa (NARP) syndrome, a large and continuously increasing number of inborn variants in the MT-ATP6 and MT-ATP8 genes have been identified as pathogenic. Variants in these genes correlate with various clinical phenotypes, which include several neurodegenerative and multisystemic disorders. In the present review, we report the pathogenic variants in mitochondrial ATP synthase genes and highlight the molecular mechanisms underlying ATP synthase deficiency that promote biochemical dysfunctions. We discuss the possible structural changes induced by the most common variants found in patients by considering the recent cryo-electron microscopy structure of human ATP synthase. Finally, we provide the state-of-the-art of all therapeutic proposals reported in the literature, including drug interventions targeting mitochondrial dysfunctions, allotopic gene expression- and nuclease-based strategies, and discuss their potential translation into clinical trials.
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Affiliation(s)
- Valentina Del Dotto
- Laboratory of Biochemistry and Mitochondrial Pathophysiology, Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy; (V.D.D.); (G.S.)
| | - Francesco Musiani
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology (FABIT), University of Bologna, 40127 Bologna, Italy;
| | - Alessandra Baracca
- Laboratory of Biochemistry and Mitochondrial Pathophysiology, Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy; (V.D.D.); (G.S.)
| | - Giancarlo Solaini
- Laboratory of Biochemistry and Mitochondrial Pathophysiology, Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy; (V.D.D.); (G.S.)
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2
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Tülüce Y, Tat NM, Kara M, Tat AM. Investigation of the biochemical and histopathological effects of vitamin C, selenium, and therapeutic ultrasound on muscle damage in rats. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2023; 396:3581-3593. [PMID: 37261476 DOI: 10.1007/s00210-023-02547-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Accepted: 05/22/2023] [Indexed: 06/02/2023]
Abstract
Muscle injury is a common type of soft tissue injury. Increased oxidative damage has been reported after muscle injuries. Therapeutic ultrasound is commonly used for such injuries. This study compared the efficacy of therapeutic ultrasound treatment and various antioxidant agents in experimental muscle injuries. For this purpose, some serum enzymes, oxidative stress, and inflammatory markers were evaluated together with histopathological examinations. Six groups were formed with 6 male Wistar albino rats in each group. These groups were control, only injury (OI), ultrasound (U), vitamin C (Vit C), selenium (S), and mixture (M). Muscle injury was caused by a laceration of the gastrocnemius muscle in all groups except the control group. No treatment was performed in the OI group. At the end of the 6-day application, all rats were sacrificed. As for serum enzymes, CK, ALT, and AST levels returned to control values in almost all treatment groups. Total oxidative status (TOS) and oxidative stress index (OSI) increased in the OI group, while they decreased in the S and M groups. In addition, the decrease in MPO activity in the blood tissue of the Vit C group was statistically significant. There were no significant changes between groups in terms of serum inflammatory markers and histological findings. This study has shown that the ingestion of vitamin C and selenium may contribute to the treatment of muscle injury in addition to therapeutic ultrasound treatment. However, further studies are needed to support these results.
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Affiliation(s)
- Yasin Tülüce
- Department of Medical Biology, Faculty of Medicine, Van Yuzuncu Yil University, 65080, Van, Turkey.
| | - Necati Muhammed Tat
- Department of Physiology, Institute of Health Sciences, Van Yuzuncu Yil University, 65080, Van, Turkey
| | - Mehmet Kara
- Department of Physiology, Faculty of Medicine, Van Yuzuncu Yil University, 65080, Van, Turkey
| | - Ayşe Merve Tat
- Department of Physiology, Institute of Health Sciences, Van Yuzuncu Yil University, 65080, Van, Turkey
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3
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Drabik K, Piecyk K, Wolny A, Szulc-Dąbrowska L, Dębska-Vielhaber G, Vielhaber S, Duszyński J, Malińska D, Szczepanowska J. Adaptation of mitochondrial network dynamics and velocity of mitochondrial movement to chronic stress present in fibroblasts derived from patients with sporadic form of Alzheimer's disease. FASEB J 2021; 35:e21586. [PMID: 33960016 DOI: 10.1096/fj.202001978rr] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 03/11/2021] [Accepted: 03/25/2021] [Indexed: 12/18/2022]
Abstract
Alzheimer's disease (AD) is one of the most common neurodegenerative diseases. Only 10% of all cases are familial form, the remaining 90% are sporadic form with unknown genetic background. The etiology of sporadic AD is still not fully understood. Pathogenesis and pathobiology of this disease are limited due to the limited number of experimental models. We used primary culture of fibroblasts derived from patients diagnosed with sporadic form of AD for investigation of dynamic properties of mitochondria, including fission-fusion process and localization of mitochondria within the cell. We observed differences in mitochondrial network organization with decreased mitochondrial transport velocity, and a drop in the frequency of fusion-fission events. These studies show how mitochondrial dynamics adapt to the conditions of long-term mitochondrial stress that prevails in cells of sporadic form of AD.
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Affiliation(s)
| | - Karolina Piecyk
- Nencki Institute of Experimental Biology, Warsaw, Poland.,Faculty of Chemistry, University of Warsaw, Warsaw, Poland
| | - Artur Wolny
- Nencki Institute of Experimental Biology, Warsaw, Poland
| | - Lidia Szulc-Dąbrowska
- Institute of Veterinary Medicine, Department of Preclinical Sciences, Warsaw University of Life Sciences, Warsaw, Poland
| | | | - Stefan Vielhaber
- Department of Neurology, Otto-von-Guericke University of Magdeburg, Magdeburg, Germany
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Chemical reversal of abnormalities in cells carrying mitochondrial DNA mutations. Nat Chem Biol 2020; 17:335-343. [PMID: 33168978 DOI: 10.1038/s41589-020-00676-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 08/30/2020] [Accepted: 09/16/2020] [Indexed: 12/24/2022]
Abstract
Mitochondrial DNA (mtDNA) mutations are the major cause of mitochondrial diseases. Cells harboring disease-related mtDNA mutations exhibit various phenotypic abnormalities, such as reduced respiration and elevated lactic acid production. Induced pluripotent stem cell (iPSC) lines derived from patients with mitochondrial disease, with high proportions of mutated mtDNA, exhibit defects in maturation into neurons or cardiomyocytes. In this study, we have discovered a small-molecule compound, which we name tryptolinamide (TLAM), that activates mitochondrial respiration in cybrids generated from patient-derived mitochondria and fibroblasts from patient-derived iPSCs. We found that TLAM inhibits phosphofructokinase-1 (PFK1), which in turn activates AMPK-mediated fatty-acid oxidation to promote oxidative phosphorylation, and redirects carbon flow from glycolysis toward the pentose phosphate pathway to reinforce anti-oxidative potential. Finally, we found that TLAM rescued the defect in neuronal differentiation of iPSCs carrying a high ratio of mutant mtDNA, suggesting that PFK1 represents a potential therapeutic target for mitochondrial diseases.
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Prognostic Factors Associating with Pro-oxidant-antioxidant Balance; Neutrophils to Lymphocytes Ratio, Vitamin D, Heat Shock Protein 27, and Red Cell Distribution Width. Arch Med Res 2020; 51:261-267. [DOI: 10.1016/j.arcmed.2020.02.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 01/19/2020] [Accepted: 02/17/2020] [Indexed: 12/17/2022]
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Pang KL, Chin KY. Emerging Anticancer Potentials of Selenium on Osteosarcoma. Int J Mol Sci 2019; 20:E5318. [PMID: 31731474 PMCID: PMC6862058 DOI: 10.3390/ijms20215318] [Citation(s) in RCA: 24] [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: 09/06/2019] [Revised: 10/05/2019] [Accepted: 10/22/2019] [Indexed: 02/07/2023] Open
Abstract
Selenium is a trace element essential to humans and forms complexes with proteins, which exert physiological functions in the body. In vitro studies suggested that selenium possesses anticancer effects and may be effective against osteosarcoma. This review aims to summarise current evidence on the anticancer activity of inorganic and organic selenium on osteosarcoma. Cellular studies revealed that inorganic and organic selenium shows cytotoxicity, anti-proliferative and pro-apoptotic effects on various osteosarcoma cell lines. These actions may be mediated by oxidative stress induced by selenium compounds, leading to the activation of p53, proapoptotic proteins and caspases. Inorganic selenium is selective towards cancer cells, but can cause non-selective cell death at a high dose. This condition challenges the controlled release of selenium from biomaterials. Selenium treatment in animals inoculated with osteosarcoma reduced the tumour size, but did not eliminate the incidence of osteosarcoma. Only one study investigated the relationship between selenium and osteosarcoma in humans, but the results were inconclusive. In summary, although selenium may exert anticancer properties on osteosarcoma in experimental model systems, its effects in humans require further investigation.
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Affiliation(s)
| | - Kok-Yong Chin
- Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Cheras, Kuala Lumpur 56000, Malaysia;
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Walczak J, Dębska-Vielhaber G, Vielhaber S, Szymański J, Charzyńska A, Duszyński J, Szczepanowska J. Distinction of sporadic and familial forms of ALS based on mitochondrial characteristics. FASEB J 2018; 33:4388-4403. [PMID: 30550341 DOI: 10.1096/fj.201801843r] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Bioenergetic failure, oxidative stress, and changes in mitochondrial morphology are common pathologic hallmarks of amyotrophic lateral sclerosis (ALS) in several cellular and animal models. Disturbed mitochondrial physiology has serious consequences for proper functioning of the cell, leading to the chronic mitochondrial stress. Mitochondria, being in the center of cellular metabolism, play a pivotal role in adaptation to stress conditions. We found that mitochondrial dysfunction and adaptation processes differ in primary fibroblasts derived from patients diagnosed with either sporadic or familial forms of ALS. The evaluation of mitochondrial parameters such as the mitochondrial membrane potential, the oxygen consumption rate, the activity and levels of respiratory chain complexes, and the levels of ATP, reactive oxygen species, and Ca2+ show that the bioenergetic properties of mitochondria are different in sporadic ALS, familial ALS, and control groups. Comparative statistical analysis of the data set (with use of principal component analysis and support vector machine) identifies and distinguishes 3 separate groups despite the small number of investigated cell lines and high variability in measured parameters. These findings could be a first step in development of a new tool for predicting sporadic and familial forms of ALS and could contribute to knowledge of its pathophysiology.-Walczak, J., Dębska-Vielhaber, G., Vielhaber, S., Szymański, J., Charzyńska, A., Duszyński, J., Szczepanowska, J. Distinction of sporadic and familial forms of ALS based on mitochondrial characteristics.
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Affiliation(s)
- Jarosław Walczak
- Laboratory of Bioenergetics and Biomembranes, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | | | - Stefan Vielhaber
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany; and
| | - Jędrzej Szymański
- Laboratory of Bioenergetics and Biomembranes, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Agata Charzyńska
- Laboratory of Bioinformatics, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Jerzy Duszyński
- Laboratory of Bioenergetics and Biomembranes, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Joanna Szczepanowska
- Laboratory of Bioenergetics and Biomembranes, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
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Malinska D, Szymański J, Patalas-Krawczyk P, Michalska B, Wojtala A, Prill M, Partyka M, Drabik K, Walczak J, Sewer A, Johne S, Luettich K, Peitsch MC, Hoeng J, Duszyński J, Szczepanowska J, van der Toorn M, Wieckowski MR. Assessment of mitochondrial function following short- and long-term exposure of human bronchial epithelial cells to total particulate matter from a candidate modified-risk tobacco product and reference cigarettes. Food Chem Toxicol 2018; 115:1-12. [PMID: 29448087 DOI: 10.1016/j.fct.2018.02.013] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 02/07/2018] [Indexed: 12/25/2022]
Abstract
Mitochondrial dysfunction caused by cigarette smoke is involved in the oxidative stress-induced pathology of airway diseases. Reducing the levels of harmful and potentially harmful constituents by heating rather than combusting tobacco may reduce mitochondrial changes that contribute to oxidative stress and cell damage. We evaluated mitochondrial function and oxidative stress in human bronchial epithelial cells (BEAS 2B) following 1- and 12-week exposures to total particulate matter (TPM) from the aerosol of a candidate modified-risk tobacco product, the Tobacco Heating System 2.2 (THS2.2), in comparison with TPM from the 3R4F reference cigarette. After 1-week exposure, 3R4F TPM had a strong inhibitory effect on mitochondrial basal and maximal oxygen consumption rates compared to TPM from THS2.2. Alterations in oxidative phosphorylation were accompanied by increased mitochondrial superoxide levels and increased levels of oxidatively damaged proteins in cells exposed to 7.5 μg/mL of 3R4F TPM or 150 μg/mL of THS2.2 TPM, while cytosolic levels of reactive oxygen species were not affected. In contrast, the 12-week exposure indicated adaptation of BEAS-2B cells to long-term stress. Together, the findings indicate that 3R4F TPM had a stronger effect on oxidative phosphorylation, gene expression and proteins involved in oxidative stress than TPM from the candidate modified-risk tobacco product THS2.2.
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Affiliation(s)
- Dominika Malinska
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland
| | - Jędrzej Szymański
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland
| | - Paulina Patalas-Krawczyk
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland
| | - Bernadeta Michalska
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland
| | - Aleksandra Wojtala
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland
| | - Monika Prill
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland
| | - Małgorzata Partyka
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland
| | - Karolina Drabik
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland
| | - Jarosław Walczak
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland
| | - Alain Sewer
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, 2000 Neuchâtel, Switzerland
| | - Stephanie Johne
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, 2000 Neuchâtel, Switzerland
| | - Karsta Luettich
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, 2000 Neuchâtel, Switzerland
| | - Manuel C Peitsch
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, 2000 Neuchâtel, Switzerland
| | - Julia Hoeng
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, 2000 Neuchâtel, Switzerland
| | - Jerzy Duszyński
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland
| | - Joanna Szczepanowska
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland
| | - Marco van der Toorn
- PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, 2000 Neuchâtel, Switzerland.
| | - Mariusz R Wieckowski
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland.
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9
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Walczak J, Partyka M, Duszyński J, Szczepanowska J. Implications of mitochondrial network organization in mitochondrial stress signalling in NARP cybrid and Rho0 cells. Sci Rep 2017; 7:14864. [PMID: 29093569 PMCID: PMC5665886 DOI: 10.1038/s41598-017-14964-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 10/19/2017] [Indexed: 01/01/2023] Open
Abstract
Mitochondrial dysfunctions lead to the generation of signalling mediators that influence the fate of that organelle. Mitochondrial dynamics and their positioning within the cell are important elements of mitochondria-nucleus communication. The aim of this project was to examine whether mitochondrial shape, distribution and fusion/fission proteins are involved in the mitochondrial stress response in a cellular model subjected to specifically designed chronic mitochondrial stress: WT human osteosarcoma cells as controls, NARP cybrid cells as mild chronic stress and Rho0 as severe chronic stress. We characterized mitochondrial distribution in these cells using confocal microscopy and evaluated the level of proteins directly involved in the mitochondrial dynamics and their regulation. We found that the organization of mitochondria within the cell is correlated with changes in the levels of proteins involved in mitochondrial dynamics and proteins responsible for regulation of this process. Induction of the autophagy/mitophagy process, which is crucial for cellular homeostasis under stress conditions was also shown. It seems that mitochondrial shape and organization within the cell are implicated in retrograde signalling in chronic mitochondrial stress.
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Affiliation(s)
- Jarosław Walczak
- Laboratory of Bioenergetics and Biomembranes, Department of Biochemistry, Nencki Institute of Experimental Biology, Polish Academy of Science, 3 Pasteur St, 02-993, Warsaw, Poland
| | - Małgorzata Partyka
- Laboratory of Bioenergetics and Biomembranes, Department of Biochemistry, Nencki Institute of Experimental Biology, Polish Academy of Science, 3 Pasteur St, 02-993, Warsaw, Poland
| | - Jerzy Duszyński
- Laboratory of Bioenergetics and Biomembranes, Department of Biochemistry, Nencki Institute of Experimental Biology, Polish Academy of Science, 3 Pasteur St, 02-993, Warsaw, Poland
| | - Joanna Szczepanowska
- Laboratory of Bioenergetics and Biomembranes, Department of Biochemistry, Nencki Institute of Experimental Biology, Polish Academy of Science, 3 Pasteur St, 02-993, Warsaw, Poland.
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López-Gallardo E, Llobet L, Emperador S, Montoya J, Ruiz-Pesini E. Effects of Tributyltin Chloride on Cybrids with or without an ATP Synthase Pathologic Mutation. ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:1399-405. [PMID: 27129022 PMCID: PMC5010394 DOI: 10.1289/ehp182] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 11/27/2015] [Accepted: 04/13/2016] [Indexed: 05/05/2023]
Abstract
BACKGROUND The oxidative phosphorylation system (OXPHOS) includes nuclear chromosome (nDNA)- and mitochondrial DNA (mtDNA)-encoded polypeptides. Many rare OXPHOS disorders, such as striatal necrosis syndromes, are caused by genetic mutations. Despite important advances in sequencing procedures, causative mutations remain undetected in some patients. It is possible that etiologic factors, such as environmental toxins, are the cause of these cases. Indeed, the inhibition of a particular enzyme by a poison could imitate the biochemical effects of pathological mutations in that enzyme. Moreover, environmental factors can modify the penetrance or expressivity of pathological mutations. OBJECTIVES We studied the interaction between mitochondrially encoded ATP synthase 6 (p.MT-ATP6) subunit and an environmental exposure that may contribute phenotypic differences between healthy individuals and patients suffering from striatal necrosis syndromes or other mitochondriopathies. METHODS We analyzed the effects of the ATP synthase inhibitor tributyltin chloride (TBTC), a widely distributed environmental factor that contaminates human food and water, on transmitochondrial cell lines with or without an ATP synthase mutation that causes striatal necrosis syndrome. Doses were selected based on TBTC concentrations previously reported in human whole blood samples. RESULTS TBTC modified the phenotypic effects caused by a pathological mtDNA mutation. Interestingly, wild-type cells treated with this xenobiotic showed similar bioenergetics when compared with the untreated mutated cells. CONCLUSIONS In addition to the known genetic causes, our findings suggest that environmental exposure to TBTC might contribute to the etiology of striatal necrosis syndromes. CITATION López-Gallardo E, Llobet L, Emperador S, Montoya J, Ruiz-Pesini E. 2016. Effects of tributyltin chloride on cybrids with or without an ATP synthase pathologic mutation. Environ Health Perspect 124:1399-1405; http://dx.doi.org/10.1289/EHP182.
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Affiliation(s)
- Ester López-Gallardo
- Departamento de Bioquímica, Biología Molecular y Celular,
- Instituto de Investigación Sanitaria de Aragón,
- CIBER de Enfermedades Raras (CIBERER), and
| | - Laura Llobet
- Departamento de Bioquímica, Biología Molecular y Celular,
- Instituto de Investigación Sanitaria de Aragón,
- CIBER de Enfermedades Raras (CIBERER), and
| | - Sonia Emperador
- Departamento de Bioquímica, Biología Molecular y Celular,
- Instituto de Investigación Sanitaria de Aragón,
- CIBER de Enfermedades Raras (CIBERER), and
| | - Julio Montoya
- Departamento de Bioquímica, Biología Molecular y Celular,
- Instituto de Investigación Sanitaria de Aragón,
- CIBER de Enfermedades Raras (CIBERER), and
- Address correspondence to E. Ruiz-Pesini, Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013-Zaragoza, Spain. Telephone: 34-976761640. E-mail: , or J. Montoya, Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013-Zaragoza, Spain. Telephone: 34-976761640. E-mail:
| | - Eduardo Ruiz-Pesini
- Departamento de Bioquímica, Biología Molecular y Celular,
- Instituto de Investigación Sanitaria de Aragón,
- CIBER de Enfermedades Raras (CIBERER), and
- Fundación ARAID, Universidad de Zaragoza, Zaragoza, Spain
- Address correspondence to E. Ruiz-Pesini, Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013-Zaragoza, Spain. Telephone: 34-976761640. E-mail: , or J. Montoya, Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013-Zaragoza, Spain. Telephone: 34-976761640. E-mail:
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Wojewoda M, Walczak J, Duszyński J, Szczepanowska J. Selenite activates the ATM kinase-dependent DNA repair pathway in human osteosarcoma cells with mitochondrial dysfunction. Biochem Pharmacol 2015; 95:170-6. [DOI: 10.1016/j.bcp.2015.03.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 03/30/2015] [Indexed: 01/22/2023]
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12
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Muzembo BA, Deguchi Y, Ngatu NR, Eitoku M, Hirota R, Suganuma N. Selenium and exposure to fibrogenic mineral dust: a mini-review. ENVIRONMENT INTERNATIONAL 2015; 77:16-24. [PMID: 25615721 DOI: 10.1016/j.envint.2015.01.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 12/28/2014] [Accepted: 01/04/2015] [Indexed: 06/04/2023]
Abstract
Individuals exposed to fibrogenic mineral dust may exhibit an impaired antioxidant system and produce high levels of reactive oxygen and nitrogen species through immune cells, contributing to the perturbation of immune cell function, inflammation, fibrosis and lung cancer. The lung diseases which are caused by inhalation of fibrogenic mineral dust, known as pneumoconioses, develop progressively and irreversibly over decades. At the moment there is no known cure. The trace element selenium has potent antioxidant and anti-inflammatory properties mediated mainly through selenoproteins. Research has demonstrated that selenium has the ability to protect against cardiovascular diseases; to kill cancer cells in vitro and reduce cancer incidence; and to immunomodulate various cellular signaling pathways. For these reasons, selenium has been proposed as a promising therapeutic agent in oxidative stress associated pathology that in theory would be beneficial for the prevention or treatment of pneumoconioses such as silicosis, asbestosis, and coal worker's pneumoconiosis. However, studies regarding selenium and occupational lung diseases are rare. The purpose of this study is to conduct a mini-review regarding the relationship between selenium and exposure to fibrogenic mineral dust with emphasis on epidemiological studies. We carried out a systematic literature search of English published studies on selenium and exposure to fibrogenic mineral dust. We found four epidemiological studies. Reviewed studies show that selenium is lower in individuals exposed to fibrogenic mineral dust. However, three out of the four reviewed studies could not confirm cause-and-effect relationships between low selenium status and exposure to fibrogenic mineral dust. This mini-review underscores the need for large follow-up and mechanistic studies for selenium to further elucidate its therapeutic effects.
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Affiliation(s)
- Basilua Andre Muzembo
- Division of Social Medicine, Department of Environmental Medicine, Kochi Medical School, Kochi University, Kochi, Japan; Research Fellow of the Japan Society for the Promotion of Science (JSPS), Tokyo, Japan.
| | - Yoji Deguchi
- School of Nursing, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Nlandu Roger Ngatu
- Division of Social Medicine, Department of Environmental Medicine, Kochi Medical School, Kochi University, Kochi, Japan; Disaster Graduate School of Health and Nursing Sciences, Disaster Nursing Global Leader program (DNGL), University of Kochi, Kochi, Japan
| | - Masamitsu Eitoku
- Division of Social Medicine, Department of Environmental Medicine, Kochi Medical School, Kochi University, Kochi, Japan
| | - Ryoji Hirota
- Division of Social Medicine, Department of Environmental Medicine, Kochi Medical School, Kochi University, Kochi, Japan
| | - Narufumi Suganuma
- Division of Social Medicine, Department of Environmental Medicine, Kochi Medical School, Kochi University, Kochi, Japan
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Fukuoh A, Cannino G, Gerards M, Buckley S, Kazancioglu S, Scialo F, Lihavainen E, Ribeiro A, Dufour E, Jacobs HT. Screen for mitochondrial DNA copy number maintenance genes reveals essential role for ATP synthase. Mol Syst Biol 2014; 10:734. [PMID: 24952591 PMCID: PMC4265055 DOI: 10.15252/msb.20145117] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The machinery of mitochondrial DNA (mtDNA) maintenance is only partially characterized and is of wide interest due to its involvement in disease. To identify novel components of this machinery, plus other cellular pathways required for mtDNA viability, we implemented a genome-wide RNAi screen in Drosophila S2 cells, assaying for loss of fluorescence of mtDNA nucleoids stained with the DNA-intercalating agent PicoGreen. In addition to previously characterized components of the mtDNA replication and transcription machineries, positives included many proteins of the cytosolic proteasome and ribosome (but not the mitoribosome), three proteins involved in vesicle transport, some other factors involved in mitochondrial biogenesis or nuclear gene expression, > 30 mainly uncharacterized proteins and most subunits of ATP synthase (but no other OXPHOS complex). ATP synthase knockdown precipitated a burst of mitochondrial ROS production, followed by copy number depletion involving increased mitochondrial turnover, not dependent on the canonical autophagy machinery. Our findings will inform future studies of the apparatus and regulation of mtDNA maintenance, and the role of mitochondrial bioenergetics and signaling in modulating mtDNA copy number.
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Affiliation(s)
- Atsushi Fukuoh
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland Department of Clinical Chemistry and Laboratory Medicine, Kyushu University Graduate school of Medical Sciences, Fukuoka, Japan Department of Medical Laboratory Science, Junshin Gakuen University, Fukuoka, Japan
| | - Giuseppe Cannino
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Mike Gerards
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Suzanne Buckley
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Selena Kazancioglu
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Filippo Scialo
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Eero Lihavainen
- Department of Signal Processing, Tampere University of Technology, Tampere, Finland
| | - Andre Ribeiro
- Department of Signal Processing, Tampere University of Technology, Tampere, Finland
| | - Eric Dufour
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Howard T Jacobs
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland Research Program of Molecular Neurology, University of Helsinki, Helsinki, Finland
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14
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Li WH, Shi YC, Tseng IL, Liao VHC. Protective efficacy of selenite against lead-induced neurotoxicity in Caenorhabditis elegans. PLoS One 2013; 8:e62387. [PMID: 23638060 PMCID: PMC3637161 DOI: 10.1371/journal.pone.0062387] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Accepted: 03/21/2013] [Indexed: 11/19/2022] Open
Abstract
Background Selenium is an essential micronutrient that has a narrow exposure window between its beneficial and toxic effects. This study investigated the protective potential of selenite (IV) against lead (Pb(II))-induced neurotoxicity in Caenorhabditis elegans. Principal Findings The results showed that Se(IV) (0.01 µM) pretreatment ameliorated the decline of locomotion behaviors (frequencies of body bends, head thrashes, and reversal ) of C. elegans that are damaged by Pb(II) (100 µM) exposure. The intracellular ROS level of C. elegans induced by Pb(II) exposure was significantly lowered by Se(IV) supplementation prior to Pb(II) exposure. Finally, Se(IV) protects AFD sensory neurons from Pb(II)-induced toxicity. Conclusions Our study suggests that Se(IV) has protective activities against Pb(II)-induced neurotoxicity through its antioxidant property.
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Affiliation(s)
- Wen-Hsuan Li
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, Taiwan
| | - Yeu-Ching Shi
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, Taiwan
| | - I-Ling Tseng
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, Taiwan
| | - Vivian Hsiu-Chuan Liao
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, Taiwan
- * E-mail:
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15
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Voets AM, Lindsey PJ, Vanherle SJ, Timmer ED, Esseling JJ, Koopman WJH, Willems PHGM, Schoonderwoerd GC, De Groote D, Poll-The BT, de Coo IFM, Smeets HJM. Patient-derived fibroblasts indicate oxidative stress status and may justify antioxidant therapy in OXPHOS disorders. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1817:1971-8. [PMID: 22796146 DOI: 10.1016/j.bbabio.2012.07.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2012] [Revised: 06/12/2012] [Accepted: 07/02/2012] [Indexed: 10/28/2022]
Abstract
Oxidative phosphorylation disorders are often associated with increased oxidative stress and antioxidant therapy is frequently given as treatment. However, the role of oxidative stress in oxidative phosphorylation disorders or patients is far from clear and consequently the preventive or therapeutic effect of antioxidants is highly anecdotic. Therefore, we performed a systematic study of a panel of oxidative stress parameters (reactive oxygen species levels, damage and defense) in fibroblasts of twelve well-characterized oxidative phosphorylation patients with a defect in the POLG1 gene, in the mitochondrial DNA-encoded tRNA-Leu gene (m.3243A>G or m.3302A>G) and in one of the mitochondrial DNA-encoded NADH dehydrogenase complex I (CI) subunits. All except two cell lines (one POLG1 and one tRNA-Leu) showed increased reactive oxygen species levels compared with controls, but only four (two CI and two tRNA-Leu) cell lines provided evidence for increased oxidative protein damage. The absence of a correlation between reactive oxygen species levels and oxidative protein damage implies differences in damage prevention or correction. This was investigated by gene expression studies, which showed adaptive and compensating changes involving antioxidants and the unfolded protein response, especially in the POLG1 group. This study indicated that patients display individual responses and that detailed analysis of fibroblasts enables the identification of patients that potentially benefit from antioxidant therapy. Furthermore, the fibroblast model can also be used to search for and test novel, more specific antioxidants or explore ways to stimulate compensatory mechanisms.
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Affiliation(s)
- A M Voets
- Department of Genetics and Cell Biology, Maastricht University, The Netherlands
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16
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Harris HR, Bergkvist L, Wolk A. Selenium intake and breast cancer mortality in a cohort of Swedish women. Breast Cancer Res Treat 2012; 134:1269-77. [PMID: 22736377 DOI: 10.1007/s10549-012-2139-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Accepted: 06/12/2012] [Indexed: 10/28/2022]
Abstract
Selenium is an important cofactor in the production of antioxidant enzymes that may influence cancer progression. Selenium intake and cancer survival has not been extensively studied; however, selenium supplementation has been demonstrated to reduce cancer mortality in nutritional intervention trials. We investigated whether dietary selenium intake was associated with survival among 3,146 women diagnosed with invasive breast cancer in the population-based Swedish Mammography Cohort. Selenium intake before breast cancer diagnosis was estimated using a food frequency questionnaire completed in 1987. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95 % confidence intervals (95 % CIs) for death from breast cancer, non-breast cancer death, and death from any cause. During 28,172 person-years of follow-up from 1987 to 2009, there were 416 breast cancer-specific deaths and 964 total deaths. Dietary selenium intake was inversely associated with breast cancer-specific mortality and overall mortality. Women in the highest quartile of selenium intake had a multivariable HR (95 % CI) of death from breast cancer of 0.69 (0.52-0.92) compared with those in the lowest quartile (P (trend) = 0.009). The inverse association between dietary selenium intake and breast cancer death appeared strongest among women who had ever smoked (HR = 0.34; 95 % CI 0.14-0.83; P (trend) = 0.01) comparing the highest to lowest quartile. Our findings suggest that selenium intake before breast cancer diagnosis may improve breast cancer-specific survival and overall survival. However, these results may be limited to populations with low intakes of selenium.
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Affiliation(s)
- Holly R Harris
- Division of Nutritional Epidemiology, The National Institute for Environmental Medicine, Karolinska Institutet, Box 210, 171 77 Stockholm, Sweden.
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17
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Szczepanowska J, Malinska D, Wieckowski MR, Duszynski J. Effect of mtDNA point mutations on cellular bioenergetics. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1817:1740-6. [PMID: 22406627 DOI: 10.1016/j.bbabio.2012.02.028] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 02/13/2012] [Accepted: 02/14/2012] [Indexed: 10/28/2022]
Abstract
This overview discusses the results of research on the effects of most frequent mtDNA point mutations on cellular bioenergetics. Thirteen proteins coded by mtDNA are crucial for oxidative phosphorylation, 11 of them constitute key components of the respiratory chain complexes I, III and IV and 2 of mitochondrial ATP synthase. Moreover, pathogenic point mutations in mitochondrial tRNAs and rRNAs generate abnormal synthesis of the mtDNA coded proteins. Thus, pathogenic point mutations in mtDNA usually disturb the level of key parameter of the oxidative phosphorylation, i.e. the electric potential on the inner mitochondrial membrane (Δψ), and in a consequence calcium signalling and mitochondrial dynamics in the cell. Mitochondrial generation of reactive oxygen species is also modified in the mutated cells. The results obtained with cultured cells and describing biochemical consequences of mtDNA point mutations are full of contradictions. Still they help elucidate the biochemical basis of pathologies and provide a valuable tool for finding remedies in the future. This article is part of a Special Issue entitled: 17th European Bioenergetics Conference (EBEC 2012).
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Affiliation(s)
- Joanna Szczepanowska
- Department of Biochemsitry, Nencki Institute of Experimental Biology, Warsaw, Poland
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18
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Selenium and its' role in the maintenance of genomic stability. Mutat Res 2012; 733:100-10. [PMID: 22234051 DOI: 10.1016/j.mrfmmm.2011.12.011] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Revised: 12/11/2011] [Accepted: 12/22/2011] [Indexed: 02/07/2023]
Abstract
Selenium (Se) is an essential micronutrient for humans, acting as a component of the unusual amino acids, selenocysteine (Se-Cys) and selenomethionine (Se-Met). Where Se levels are low, the cell cannot synthesise selenoproteins, although some selenoproteins and some tissues are prioritised over others. Characterised functions of known selenoproteins, include selenium transport (selenoprotein P), antioxidant/redox properties (glutathione peroxidases (GPxs), thioredoxin reductases and selenoprotein P) and anti-inflammatory properties (selenoprotein S and GPx4). Various forms of Se are consumed as part of a normal diet, or as a dietary supplement. Supplementation of tissue culture media, animal or human diets with moderate levels of certain Se compounds may protect against the formation of DNA adducts, DNA or chromosome breakage, and chromosome gain or loss. Protective effects have also been shown on mitochondrial DNA, and on telomere length and function. Some of the effects of Se compounds on gene expression may relate to modulation of DNA methylation or inhibition of histone deacetylation. Despite a large number of positive effects of selenium and selenoproteins in various model systems, there have now been some human clinical trials that have shown adverse effects of Se supplementation, according to various endpoints. Too much Se is as harmful as too little, with animal models showing a "U"-shaped efficacy curve. Current recommended daily allowances differ among countries, but are generally based on the amount of Se necessary to saturate GPx enzymes. However, increasing evidence suggests that other enzymes may be more important than GPx for Se action, that optimal levels may depend upon the form of Se being ingested, and vary according to genotype. New paradigms, possibly involving nutrigenomic tools, will be necessary to optimise the forms and levels of Se desirable for maximum protection of genomic stability in all humans.
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19
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NARP mutation and mtDNA depletion trigger mitochondrial biogenesis which can be modulated by selenite supplementation. Int J Biochem Cell Biol 2011; 43:1178-86. [DOI: 10.1016/j.biocel.2011.04.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Revised: 04/11/2011] [Accepted: 04/18/2011] [Indexed: 11/19/2022]
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20
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Effect of selenite on basic mitochondrial function in human osteosarcoma cells with chronic mitochondrial stress. Mitochondrion 2011; 12:149-55. [PMID: 21742063 DOI: 10.1016/j.mito.2011.06.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 06/20/2011] [Accepted: 06/24/2011] [Indexed: 11/22/2022]
Abstract
Mitochondrial chronic stress that originates from defective mitochondria is implicated in a growing list of human diseases. To enhance understanding of pathophysiology of chronic mitochondrial dysfunction we investigated human osteosarcoma cells with 2 types of chronic stress: corresponding to the mutation in ATP synthase subunit 6 encoded by mtDNA (NARP syndrome-mild stress) and to a total lack of mtDNA (Rho0 cells-heavy stress). We previously found that selenium influenced mitochondrial stress response and lowered ROS production. Therefore, in this study effect of selenite on other mitochondrial parameters was investigated. We showed that presence of selenium improved survival of starved cells, modified organization of mitochondrial network in NARP cybrids and decreased cytosolic calcium level in NARP and Rho0 cells. Selenium did not affect mitochondrial membrane potential, ATP level, activity of ATP synthase and activity of complex II of the respiratory chain.
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21
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Fairweather-Tait SJ, Bao Y, Broadley MR, Collings R, Ford D, Hesketh JE, Hurst R. Selenium in human health and disease. Antioxid Redox Signal 2011; 14:1337-83. [PMID: 20812787 DOI: 10.1089/ars.2010.3275] [Citation(s) in RCA: 770] [Impact Index Per Article: 59.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This review covers current knowledge of selenium in the environment, dietary intakes, metabolism and status, functions in the body, thyroid hormone metabolism, antioxidant defense systems and oxidative metabolism, and the immune system. Selenium toxicity and links between deficiency and Keshan disease and Kashin-Beck disease are described. The relationships between selenium intake/status and various health outcomes, in particular gastrointestinal and prostate cancer, cardiovascular disease, diabetes, and male fertility, are reviewed, and recent developments in genetics of selenoproteins are outlined. The rationale behind current dietary reference intakes of selenium is explained, and examples of differences between countries and/or expert bodies are given. Throughout the review, gaps in knowledge and research requirements are identified. More research is needed to improve our understanding of selenium metabolism and requirements for optimal health. Functions of the majority of the selenoproteins await characterization, the mechanism of absorption has yet to be identified, measures of status need to be developed, and effects of genotype on metabolism require further investigation. The relationships between selenium intake/status and health, or risk of disease, are complex but require elucidation to inform clinical practice, to refine dietary recommendations, and to develop effective public health policies.
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Affiliation(s)
- Susan J Fairweather-Tait
- School of Medicine, Health Policy and Practice, University of East Anglia, Norwich, Norfolk, United Kingdom.
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22
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Trevisan R, Mello DF, Fisher AS, Schuwerack PM, Dafre AL, Moody AJ. Selenium in water enhances antioxidant defenses and protects against copper-induced DNA damage in the blue mussel Mytilus edulis. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2011; 101:64-71. [PMID: 20947183 DOI: 10.1016/j.aquatox.2010.09.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 08/31/2010] [Accepted: 09/04/2010] [Indexed: 05/10/2023]
Abstract
Selenium and copper are naturally occurring elements in the environment that have important roles in cellular function. Selenium is known for its role in antioxidant defense, whereas copper is a redox-active metal capable of acting as a pro-oxidant. We investigated the effects of short term selenium (Na(2)SeO(3)) supplementation (4 μg/L for 3 days) on antioxidant parameters of the blue mussel, Mytilus edulis, and its possible protective effects against a subsequent copper (CuSO(4)) exposure (56 μg/L for 3 days). Selenium supplementation caused a 4-fold increase in glutathione levels in gills. The activity of selenium-dependent glutathione peroxidase was modulated by selenium in gills (2-fold increase) and also in cell-free haemolymph (40% increase). Copper exposure produced decreases in protein thiol levels (35%) and in thioredoxin reductase activity (60%) in gills and induced an increase in DNA damage in haemocytes (70% increase in % tail DNA observed using the comet assay). The decrease in thioredoxin reductase activity may constitute a mechanism of copper toxicity in bivalves, warranting further investigation. Pre-treatment with selenium largely prevented these deleterious effects of copper on protein thiols, thioredoxin reductase activity and DNA damage. The results suggest that induction of key antioxidant defenses such as glutathione and selenium-dependent glutathione peroxidase, as a result of selenium supplementation, may play an important role in protection of aquatic organisms against oxidative stress.
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Affiliation(s)
- Rafael Trevisan
- Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
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