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Wang Y, Lilienfeldt N, Hekimi S. Understanding coenzyme Q. Physiol Rev 2024; 104:1533-1610. [PMID: 38722242 DOI: 10.1152/physrev.00040.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 04/08/2024] [Accepted: 05/01/2024] [Indexed: 08/11/2024] Open
Abstract
Coenzyme Q (CoQ), also known as ubiquinone, comprises a benzoquinone head group and a long isoprenoid side chain. It is thus extremely hydrophobic and resides in membranes. It is best known for its complex function as an electron transporter in the mitochondrial electron transport chain (ETC) but is also required for several other crucial cellular processes. In fact, CoQ appears to be central to the entire redox balance of the cell. Remarkably, its structure and therefore its properties have not changed from bacteria to vertebrates. In metazoans, it is synthesized in all cells and is found in most, and maybe all, biological membranes. CoQ is also known as a nutritional supplement, mostly because of its involvement with antioxidant defenses. However, whether there is any health benefit from oral consumption of CoQ is not well established. Here we review the function of CoQ as a redox-active molecule in the ETC and other enzymatic systems, its role as a prooxidant in reactive oxygen species generation, and its separate involvement in antioxidant mechanisms. We also review CoQ biosynthesis, which is particularly complex because of its extreme hydrophobicity, as well as the biological consequences of primary and secondary CoQ deficiency, including in human patients. Primary CoQ deficiency is a rare inborn condition due to mutation in CoQ biosynthetic genes. Secondary CoQ deficiency is much more common, as it accompanies a variety of pathological conditions, including mitochondrial disorders as well as aging. In this context, we discuss the importance, but also the great difficulty, of alleviating CoQ deficiency by CoQ supplementation.
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Affiliation(s)
- Ying Wang
- Department of Biology, McGill University, Montreal, Quebec, Canada
| | - Noah Lilienfeldt
- Department of Biology, McGill University, Montreal, Quebec, Canada
| | - Siegfried Hekimi
- Department of Biology, McGill University, Montreal, Quebec, Canada
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Fakhrolmobasheri M, Hosseini MS, Shahrokh SG, Mohammadi Z, Kahlani MJ, Majidi SE, Zeinalian M. Coenzyme Q10 and Its Therapeutic Potencies Against COVID-19 and Other Similar Infections: A Molecular Review. Adv Pharm Bull 2023; 13:233-243. [PMID: 37342382 PMCID: PMC10278218 DOI: 10.34172/apb.2023.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 10/09/2021] [Accepted: 11/06/2021] [Indexed: 08/25/2023] Open
Abstract
Purpose: New lethal coronavirus disease 2019 (COVID-19), currently, has been converted to a disastrous pandemic worldwide. As there has been found no definitive treatment for the infection in this review we focused on molecular aspects of coenzyme Q10 (CoQ10) and possible therapeutic potencies of CoQ10 against COVID-19 and similar infections. Methods: This is a narrative review in which we used some authentic resources including PubMed, ISI, Scopus, Science Direct, Cochrane, and some preprint databases, the molecular aspects of CoQ10 effects, regarding to the COVID-19 pathogenesis, have been analyzed and discussed. Results: CoQ10 is an essential cofactor in the electron transport chain of the phosphorylative oxidation system. It is a powerful lipophilic antioxidant, anti-apoptotic, immunomodulatory and anti-inflammatory supplement which has been tested for the management and prevention of a variety of diseases particularly diseases with inflammatory pathogenesis. CoQ10 is a strong anti-inflammatory agent which can reduce tumor necrosis factor-α (TNF-α), interleukin (IL)- 6, C-reactive protein (CRP), and other inflammatory cytokines. The cardio-protective role of CoQ10 in improving viral myocarditis and drug induced cardiotoxicity has been determined in different studies. CoQ10 could also improve the interference in the RAS system caused by COVID-19 through exerting anti-Angiotensin II effects and decreasing oxidative stress. CoQ10 passes easily through blood-brain barrier (BBB). As a neuroprotective agent CoQ10 can reduce oxidative stress and modulate the immunologic reactions. These properties may help to reduce CNS inflammation and prevent BBB damage and neuronal apoptosis in COVID-19 patients. Conclusion: CoQ10 supplementation may prevent the COVID-19-induced morbidities with a potential protective role against the deleterious consequences of the disease, further clinical evaluations are encouraged.
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Affiliation(s)
- Mohammad Fakhrolmobasheri
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical sciences, Isfahan, Iran
| | - Mahnaz-Sadat Hosseini
- School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Seyedeh-Ghazal Shahrokh
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical sciences, Isfahan, Iran
| | - Zahra Mohammadi
- Department of Biology, Faculty of Sciences, Shahid Bahonar University of Kerman, Kerman, Iran
| | - Mohammad-Javad Kahlani
- Department of Cell and Molecular Biology and Microbiology, Faculty of Biological Sciences and Technologies, University of Isfahan, Isfahan, Iran
| | - Seyed-Erfan Majidi
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical sciences, Isfahan, Iran
| | - Mehrdad Zeinalian
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical sciences, Isfahan, Iran
- Pediatric Inherited Disease Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran
- Iranians Cancer Control Charity Institute (MACSA), Isfahan, Iran
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Coenzyme Q at the Hinge of Health and Metabolic Diseases. Antioxidants (Basel) 2021; 10:antiox10111785. [PMID: 34829656 PMCID: PMC8615162 DOI: 10.3390/antiox10111785] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 10/28/2021] [Accepted: 11/04/2021] [Indexed: 12/13/2022] Open
Abstract
Coenzyme Q is a unique lipidic molecule highly conserved in evolution and essential to maintaining aerobic metabolism. It is endogenously synthesized in all cells by a very complex pathway involving a group of nuclear genes that share high homology among species. This pathway is tightly regulated at transcription and translation, but also by environment and energy requirements. Here, we review how coenzyme Q reacts within mitochondria to promote ATP synthesis and also integrates a plethora of metabolic pathways and regulates mitochondrial oxidative stress. Coenzyme Q is also located in all cellular membranes and plasma lipoproteins in which it exerts antioxidant function, and its reaction with different extramitochondrial oxidoreductases contributes to regulate the cellular redox homeostasis and cytosolic oxidative stress, providing a key factor in controlling various apoptosis mechanisms. Coenzyme Q levels can be decreased in humans by defects in the biosynthesis pathway or by mitochondrial or cytosolic dysfunctions, leading to a highly heterogeneous group of mitochondrial diseases included in the coenzyme Q deficiency syndrome. We also review the importance of coenzyme Q levels and its reactions involved in aging and age-associated metabolic disorders, and how the strategy of its supplementation has had benefits for combating these diseases and for physical performance in aging.
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Ross D, Siegel D. The diverse functionality of NQO1 and its roles in redox control. Redox Biol 2021; 41:101950. [PMID: 33774477 PMCID: PMC8027776 DOI: 10.1016/j.redox.2021.101950] [Citation(s) in RCA: 191] [Impact Index Per Article: 63.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 03/15/2021] [Accepted: 03/16/2021] [Indexed: 12/20/2022] Open
Abstract
In this review, we summarize the multiple functions of NQO1, its established roles in redox processes and potential roles in redox control that are currently emerging. NQO1 has attracted interest due to its roles in cell defense and marked inducibility during cellular stress. Exogenous substrates for NQO1 include many xenobiotic quinones. Since NQO1 is highly expressed in many solid tumors, including via upregulation of Nrf2, the design of compounds activated by NQO1 and NQO1-targeted drug delivery have been active areas of research. Endogenous substrates have also been proposed and of relevance to redox stress are ubiquinone and vitamin E quinone, components of the plasma membrane redox system. Established roles for NQO1 include a superoxide reductase activity, NAD+ generation, interaction with proteins and their stabilization against proteasomal degradation, binding and regulation of mRNA translation and binding to microtubules including the mitotic spindles. We also summarize potential roles for NQO1 in regulation of glucose and insulin metabolism with relevance to diabetes and the metabolic syndrome, in Alzheimer's disease and in aging. The conformation and molecular interactions of NQO1 can be modulated by changes in the pyridine nucleotide redox balance suggesting that NQO1 may function as a redox-dependent molecular switch.
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Affiliation(s)
- David Ross
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA.
| | - David Siegel
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
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Hidalgo-Gutiérrez A, González-García P, Díaz-Casado ME, Barriocanal-Casado E, López-Herrador S, Quinzii CM, López LC. Metabolic Targets of Coenzyme Q10 in Mitochondria. Antioxidants (Basel) 2021; 10:520. [PMID: 33810539 PMCID: PMC8066821 DOI: 10.3390/antiox10040520] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/14/2021] [Accepted: 03/23/2021] [Indexed: 12/11/2022] Open
Abstract
Coenzyme Q10 (CoQ10) is classically viewed as an important endogenous antioxidant and key component of the mitochondrial respiratory chain. For this second function, CoQ molecules seem to be dynamically segmented in a pool attached and engulfed by the super-complexes I + III, and a free pool available for complex II or any other mitochondrial enzyme that uses CoQ as a cofactor. This CoQ-free pool is, therefore, used by enzymes that link the mitochondrial respiratory chain to other pathways, such as the pyrimidine de novo biosynthesis, fatty acid β-oxidation and amino acid catabolism, glycine metabolism, proline, glyoxylate and arginine metabolism, and sulfide oxidation metabolism. Some of these mitochondrial pathways are also connected to metabolic pathways in other compartments of the cell and, consequently, CoQ could indirectly modulate metabolic pathways located outside the mitochondria. Thus, we review the most relevant findings in all these metabolic functions of CoQ and their relations with the pathomechanisms of some metabolic diseases, highlighting some future perspectives and potential therapeutic implications.
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Affiliation(s)
- Agustín Hidalgo-Gutiérrez
- Departamento de Fisiología, Facultad de Medicina, Universidad de Granada, 18016 Granada, Spain; (P.G.-G.); (M.E.D.-C.); (E.B.-C.); (S.L.-H.)
- Centro de Investigación Biomédica, Instituto de Biotecnología, Universidad de Granada, 18016 Granada, Spain
| | - Pilar González-García
- Departamento de Fisiología, Facultad de Medicina, Universidad de Granada, 18016 Granada, Spain; (P.G.-G.); (M.E.D.-C.); (E.B.-C.); (S.L.-H.)
- Centro de Investigación Biomédica, Instituto de Biotecnología, Universidad de Granada, 18016 Granada, Spain
| | - María Elena Díaz-Casado
- Departamento de Fisiología, Facultad de Medicina, Universidad de Granada, 18016 Granada, Spain; (P.G.-G.); (M.E.D.-C.); (E.B.-C.); (S.L.-H.)
- Centro de Investigación Biomédica, Instituto de Biotecnología, Universidad de Granada, 18016 Granada, Spain
| | - Eliana Barriocanal-Casado
- Departamento de Fisiología, Facultad de Medicina, Universidad de Granada, 18016 Granada, Spain; (P.G.-G.); (M.E.D.-C.); (E.B.-C.); (S.L.-H.)
- Centro de Investigación Biomédica, Instituto de Biotecnología, Universidad de Granada, 18016 Granada, Spain
| | - Sergio López-Herrador
- Departamento de Fisiología, Facultad de Medicina, Universidad de Granada, 18016 Granada, Spain; (P.G.-G.); (M.E.D.-C.); (E.B.-C.); (S.L.-H.)
- Centro de Investigación Biomédica, Instituto de Biotecnología, Universidad de Granada, 18016 Granada, Spain
| | - Catarina M. Quinzii
- Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA;
| | - Luis C. López
- Departamento de Fisiología, Facultad de Medicina, Universidad de Granada, 18016 Granada, Spain; (P.G.-G.); (M.E.D.-C.); (E.B.-C.); (S.L.-H.)
- Centro de Investigación Biomédica, Instituto de Biotecnología, Universidad de Granada, 18016 Granada, Spain
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Ross D, Siegel D. Functions of NQO1 in Cellular Protection and CoQ 10 Metabolism and its Potential Role as a Redox Sensitive Molecular Switch. Front Physiol 2017; 8:595. [PMID: 28883796 PMCID: PMC5573868 DOI: 10.3389/fphys.2017.00595] [Citation(s) in RCA: 207] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 08/02/2017] [Indexed: 01/25/2023] Open
Abstract
NQO1 is one of the two major quinone reductases in mammalian systems. It is highly inducible and plays multiple roles in cellular adaptation to stress. A prevalent polymorphic form of NQO1 results in an absence of NQO1 protein and activity so it is important to elucidate the specific cellular functions of NQO1. Established roles of NQO1 include its ability to prevent certain quinones from one electron redox cycling but its role in quinone detoxification is dependent on the redox stability of the hydroquinone generated by two-electron reduction. Other documented roles of NQO1 include its ability to function as a component of the plasma membrane redox system generating antioxidant forms of ubiquinone and vitamin E and at high levels, as a direct superoxide reductase. Emerging roles of NQO1 include its function as an efficient intracellular generator of NAD+ for enzymes including PARP and sirtuins which has gained particular attention with respect to metabolic syndrome. NQO1 interacts with a growing list of proteins, including intrinsically disordered proteins, protecting them from 20S proteasomal degradation. The interactions of NQO1 also extend to mRNA. Recent identification of NQO1 as a mRNA binding protein have been investigated in more detail using SERPIN1A1 (which encodes the serine protease inhibitor α-1-antitrypsin) as a target mRNA and indicate a role of NQO1 in control of translation of α-1-antitrypsin, an important modulator of COPD and obesity related metabolic syndrome. NQO1 undergoes structural changes and alterations in its ability to bind other proteins as a result of the cellular reduced/oxidized pyridine nucleotide ratio. This suggests NQO1 may act as a cellular redox switch potentially altering its interactions with other proteins and mRNA as a result of the prevailing redox environment.
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Affiliation(s)
- David Ross
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy, University of Colorado Anschutz Medical CampusAurora, CO, United States
| | - David Siegel
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy, University of Colorado Anschutz Medical CampusAurora, CO, United States
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López-Lluch G, Navas P. Calorie restriction as an intervention in ageing. J Physiol 2016; 594:2043-60. [PMID: 26607973 PMCID: PMC4834802 DOI: 10.1113/jp270543] [Citation(s) in RCA: 170] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Accepted: 11/21/2015] [Indexed: 12/20/2022] Open
Abstract
Ageing causes loss of function in tissues and organs, is accompanied by a chronic inflammatory process and affects life- and healthspan. Calorie restriction (CR) is a non-genetic intervention that prevents age-associated diseases and extends longevity in most of the animal models studied so far. CR produces a pleiotropic effect and improves multiple metabolic pathways, generating benefits to the whole organism. Among the effects of CR, modulation of mitochondrial activity and a decrease in oxidative damage are two of the hallmarks. Oxidative damage is reduced by the induction of endogenous antioxidant systems and modulation of the peroxidability index in cell membranes. Mitochondrial activity changes are regulated by inhibition of IGF-1 and Target of Rapamycin (TOR)-dependent activities and activation of AMP-dependent kinase (AMPK) and the sirtuin family of proteins. The activity of PGC-1α and FoxO is regulated by these systems and is involved in mitochondria biogenesis, oxidative metabolism activity and mitochondrial turnover. The use of mimetics and the regulation of common factors have demonstrated that these molecular pathways are essential to explain the effect of CR in the organism. Finally, the anti-inflammatory effect of CR is an interesting emerging factor to be taken into consideration. In the present revision we focus on the general effect of CR and other mimetics in longevity, focusing especially on the cardiovascular system and skeletal muscle.
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Affiliation(s)
- Guillermo López-Lluch
- Universidad Pablo de Olavide, Centro Andaluz de Biología del Desarrollo, CABD-CSIC, CIBERER, Instituto de Salud Carlos III, Carretera de Utrera km. 1, 41013, Sevilla, Spain
| | - Plácido Navas
- Universidad Pablo de Olavide, Centro Andaluz de Biología del Desarrollo, CABD-CSIC, CIBERER, Instituto de Salud Carlos III, Carretera de Utrera km. 1, 41013, Sevilla, Spain
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López-Domínguez JA, Khraiwesh H, González-Reyes JA, López-Lluch G, Navas P, Ramsey JJ, de Cabo R, Burón MI, Villalba JM. Dietary fat modifies mitochondrial and plasma membrane apoptotic signaling in skeletal muscle of calorie-restricted mice. AGE (DORDRECHT, NETHERLANDS) 2013; 35:2027-2044. [PMID: 23179253 PMCID: PMC3824980 DOI: 10.1007/s11357-012-9492-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 11/05/2012] [Indexed: 02/15/2024]
Abstract
Calorie restriction decreases skeletal muscle apoptosis, and this phenomenon has been mechanistically linked to its protective action against sarcopenia of aging. Alterations in lipid composition of membranes have been related with the beneficial effects of calorie restriction. However, no study has been designed to date to elucidate if different dietary fat sources with calorie restriction modify apoptotic signaling in skeletal muscle. We show that a 6-month calorie restriction decreased the activity of the plasma membrane neutral sphingomyelinase, although caspase-8/10 activity was not altered, in young adult mice. Lipid hydroperoxides, Bax levels, and cytochrome c and AIF release/accumulation into the cytosol were also decreased, although caspase-9 activity was unchanged. No alterations in caspase-3 and apoptotic index (DNA fragmentation) were observed, but calorie restriction improved structural features of gastrocnemius fibers by increasing cross-sectional area and decreasing circularity of fibers in cross sections. Changing dietary fat with calorie restriction produced substantial alterations of apoptotic signaling. Fish oil augmented the protective effect of calorie restriction decreasing plasma membrane neutral sphingomyelinase, Bax levels, caspase-8/10, and -9 activities, while increasing levels of the antioxidant coenzyme Q at the plasma membrane, and potentiating the increase of cross-sectional area and the decrease of fiber circularity in cross sections. Many of these changes were not found when we used lard. Our data support that dietary fish oil with calorie restriction produces a cellular anti-apoptotic environment in skeletal muscle with a downregulation of components involved in the initial stages of apoptosis engagement, both at the plasma membrane and the mitochondria.
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Affiliation(s)
- José Alberto López-Domínguez
- />Departamento de Biología Celular, Fisiología e Inmunología, Universidad de Córdoba, Campus de Excelencia Internacional Agroalimentario ceiA3, Campus Rabanales Edificio Severo Ochoa, 3ª planta, Córdoba, 14014 Spain
| | - Husam Khraiwesh
- />Departamento de Biología Celular, Fisiología e Inmunología, Universidad de Córdoba, Campus de Excelencia Internacional Agroalimentario ceiA3, Campus Rabanales Edificio Severo Ochoa, 3ª planta, Córdoba, 14014 Spain
| | - José Antonio González-Reyes
- />Departamento de Biología Celular, Fisiología e Inmunología, Universidad de Córdoba, Campus de Excelencia Internacional Agroalimentario ceiA3, Campus Rabanales Edificio Severo Ochoa, 3ª planta, Córdoba, 14014 Spain
| | - Guillermo López-Lluch
- />Centro Andaluz de Biología del Desarrollo (CABD), Universidad Pablo de Olavide-CSIC, and CIBERER (Instituto de Salud Carlos III), Sevilla, Spain
| | - Plácido Navas
- />Centro Andaluz de Biología del Desarrollo (CABD), Universidad Pablo de Olavide-CSIC, and CIBERER (Instituto de Salud Carlos III), Sevilla, Spain
| | - Jon Jay Ramsey
- />VM Molecular Biosciences, University of California, Davis, CA 95616 USA
| | - Rafael de Cabo
- />Laboratory of Experimental Gerontology, National Institute of Aging, Baltimore, NIH USA
| | - María Isabel Burón
- />Departamento de Biología Celular, Fisiología e Inmunología, Universidad de Córdoba, Campus de Excelencia Internacional Agroalimentario ceiA3, Campus Rabanales Edificio Severo Ochoa, 3ª planta, Córdoba, 14014 Spain
| | - José M. Villalba
- />Departamento de Biología Celular, Fisiología e Inmunología, Universidad de Córdoba, Campus de Excelencia Internacional Agroalimentario ceiA3, Campus Rabanales Edificio Severo Ochoa, 3ª planta, Córdoba, 14014 Spain
- />Departamento de Biología Celular, Fisiología e Inmunología, Universidad de Córdoba, Campus de Excelencia Agroalimentario ceiA3, Edificio Severo Ochoa, 3ª planta, Campus Rabanales, Córdoba, 14014 Spain
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Navas P, Villalba JM, de Cabo R. The importance of plasma membrane coenzyme Q in aging and stress responses. Mitochondrion 2007; 7 Suppl:S34-40. [PMID: 17482527 DOI: 10.1016/j.mito.2007.02.010] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2006] [Revised: 01/26/2007] [Accepted: 02/03/2007] [Indexed: 02/02/2023]
Abstract
The plasma membrane of eukaryotic cells is the limit to interact with the environment. This position implies receiving stress signals that affects its components such as phospholipids. Inserted inside these components is coenzyme Q that is a redox compound acting as antioxidant. Coenzyme Q is reduced by diverse dehydrogenase enzymes mainly NADH-cytochrome b(5) reductase and NAD(P)H:quinone reductase 1. Reduced coenzyme Q can prevent lipid peroxidation chain reaction by itself or by reducing other antioxidants such as alpha-tocopherol and ascorbate. The group formed by antioxidants and the enzymes able to reduce coenzyme Q constitutes a plasma membrane redox system that is regulated by conditions that induce oxidative stress. Growth factor removal, ethidium bromide-induced rho degrees cells, and vitamin E deficiency are some of the conditions where both coenzyme Q and its reductases are increased in the plasma membrane. This antioxidant system in the plasma membrane has been observed to participate in the healthy aging induced by calorie restriction. Furthermore, coenzyme Q regulates the release of ceramide from sphingomyelin, which is concentrated in the plasma membrane. This results from the non-competitive inhibition of the neutral sphingomyelinase by coenzyme Q particularly by its reduced form. Coenzyme Q in the plasma membrane is then the center of a complex antioxidant system preventing the accumulation of oxidative damage and regulating the externally initiated ceramide signaling pathway.
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Affiliation(s)
- Plácido Navas
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide-CSIC, 41013 Sevilla, Spain.
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