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Mahapatra G, Gao Z, Bateman JR, Lockhart SN, Bergstrom J, Piloso JE, Craft S, Molina AJA. Peripheral Blood Cells From Older Adults Exhibit Sex-Associated Differences in Mitochondrial Function. J Gerontol A Biol Sci Med Sci 2024; 79:glae098. [PMID: 38602189 PMCID: PMC11059251 DOI: 10.1093/gerona/glae098] [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: 11/22/2023] [Indexed: 04/12/2024] Open
Abstract
Blood-based mitochondrial bioenergetic profiling is a feasible, economical, and minimally invasive approach that can be used to examine mitochondrial function and energy metabolism in human subjects. In this study, we use 2 complementary respirometric techniques to evaluate mitochondrial bioenergetics in both intact and permeabilized peripheral blood mononuclear cells (PBMCs) and platelets to examine sex dimorphism in mitochondrial function among older adults. Employing equal numbers of PBMCs and platelets to assess mitochondrial bioenergetics, we observe significantly higher respiration rates in female compared to male participants. Mitochondrial bioenergetic differences remain significant after controlling for independent parameters including demographic parameters (age, years of education), and cognitive parameters (mPACC5, COGDX). Our study illustrates that circulating blood cells, immune cells in particular, have distinctly different mitochondrial bioenergetic profiles between females and males. These differences should be taken into account as blood-based bioenergetic profiling is now commonly used to understand the role of mitochondrial bioenergetics in human health and aging.
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Affiliation(s)
- Gargi Mahapatra
- Division of Geriatrics, Gerontology, and Palliative Care, Department of Medicine, University of California San Diego School of Medicine, La Jolla, California, USA
| | - Zhengrong Gao
- Section on Gerontology and Geriatrics, Department of Internal Medicine, Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest Baptist Medical Center, Winston-Salem, North Carolina, USA
| | - James R Bateman
- Department of Neurology, Wake Forest Baptist Medical Center, Winston-Salem, North Carolina, USA
- Section on Gerontology and Geriatrics, Department of Internal Medicine, Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest Baptist Medical Center, Winston-Salem, North Carolina, USA
| | - Samuel Neal Lockhart
- Section on Gerontology and Geriatrics, Department of Internal Medicine, Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest Baptist Medical Center, Winston-Salem, North Carolina, USA
| | - Jaclyn Bergstrom
- Division of Geriatrics, Gerontology, and Palliative Care, Department of Medicine, University of California San Diego School of Medicine, La Jolla, California, USA
| | - Jemima Elizabeth Piloso
- Section on Gerontology and Geriatrics, Department of Internal Medicine, Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest Baptist Medical Center, Winston-Salem, North Carolina, USA
| | - Suzanne Craft
- Section on Gerontology and Geriatrics, Department of Internal Medicine, Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest Baptist Medical Center, Winston-Salem, North Carolina, USA
| | - Anthony J A Molina
- Division of Geriatrics, Gerontology, and Palliative Care, Department of Medicine, University of California San Diego School of Medicine, La Jolla, California, USA
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Shen W, Chen H, Shih C, Samet J, Tong H. Modulatory effects of dietary saturated fatty acids on platelet mitochondrial function following short-term exposure to ambient Particulate Matter (PM 2.5). JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2024; 87:215-226. [PMID: 38111233 DOI: 10.1080/15287394.2023.2292709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2023]
Abstract
Exposure to ambient fine particulate matter (PM2.5) was found to produce vascular injury, possibly by activating platelets within days after exposure. The aim of this study was to investigate the modulatory effects of dietary saturated fatty acids on platelet mitochondrial respiratory parameters following short-term inhalational exposure to PM2.5. A total of 22 healthy male volunteers were recruited from the Research Triangle area of North Carolina. Platelets were isolated from fresh whole blood samples and mitochondrial respiratory parameters were measured using an extracellular flux analyzer. Intake of saturated fat was averaged from multiple 24-hr dietary recalls. Daily ambient PM2.5 concentrations were obtained from ambient air quality monitoring stations. Correlation and ANOVA were used in data analyses, along with the pick-a-point method and the Johnson-Neyman technique for probing moderation. After controlling for age and omega-3 index, the intake of dietary saturated fatty acids after reaching 9.3% or higher of the total caloric intake significantly moderated the associations between PM2.5 exposure and several platelet mitochondrial respiratory parameters. In conclusion, dietary saturated fatty acids above 9.3% of total caloric intake influenced the relationship between short-term PM2.5 exposure and platelet mitochondrial respiration. Further research is needed to understand these associations and their implications for cardiovascular health.
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Affiliation(s)
- Wan Shen
- Oak Ridge Institute for Science and Education, Oak Ridge, TN, USA
- Food and Nutrition Program, Department of Public and Allied Health, Bowling Green State University, Bowling Green, OH USA
| | - Hao Chen
- Oak Ridge Institute for Science and Education, Oak Ridge, TN, USA
| | - Chiahao Shih
- Department of Emergency Medicine, University of Toledo, Toledo, OH, USA
| | - James Samet
- Public Health and Integrated Toxicology Division, US Environmental Protection Agency, Chapel Hill, WA, USA
| | - Haiyan Tong
- Public Health and Integrated Toxicology Division, US Environmental Protection Agency, Chapel Hill, WA, USA
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Vernerova A, Garcia-Souza LF, Soucek O, Kostal M, Rehacek V, Kujovska Krcmova L, Gnaiger E, Sobotka O. Mitochondrial Respiration of Platelets: Comparison of Isolation Methods. Biomedicines 2021; 9:biomedicines9121859. [PMID: 34944675 PMCID: PMC8698846 DOI: 10.3390/biomedicines9121859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/27/2021] [Accepted: 12/01/2021] [Indexed: 11/30/2022] Open
Abstract
Multiple non-aggregatory functions of human platelets (PLT) are widely acknowledged, yet their functional examination is limited mainly due to a lack of standardized isolation and analytic methods. Platelet apheresis (PA) is an established clinical method for PLT isolation aiming at the treatment of bleeding diathesis in severe thrombocytopenia. On the other hand, density gradient centrifugation (DC) is an isolation method applied in research for the analysis of the mitochondrial metabolic profile of oxidative phosphorylation (OXPHOS) in PLT obtained from small samples of human blood. We studied PLT obtained from 29 healthy donors by high-resolution respirometry for comparison of PA and DC isolates. ROUTINE respiration and electron transfer capacity of living PLT isolated by PA were significantly higher than in the DC group, whereas plasma membrane permeabilization resulted in a 57% decrease of succinate oxidation in PA compared to DC. These differences were eliminated after washing the PA platelets with phosphate buffer containing 10 mmol·L−1 ethylene glycol-bis (2-aminoethyl ether)-N,N,N′,N′-tetra-acetic acid, suggesting that several components, particularly Ca2+ and fuel substrates, were carried over into the respiratory assay from the serum in PA. A simple washing step was sufficient to enable functional mitochondrial analysis in subsamples obtained from PA. The combination of the standard clinical PA isolation procedure with PLT quality control and routine mitochondrial OXPHOS diagnostics meets an acute clinical demand in biomedical research of patients suffering from thrombocytopenia and metabolic diseases.
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Affiliation(s)
- Andrea Vernerova
- Department of Analytical Chemistry, Faculty of Pharmacy in Hradec Kralove, Charles University, Akademika Heyrovskeho 1203/8, 500 05 Hradec Kralove, Czech Republic; (A.V.); (L.K.K.)
- Department of Clinical Biochemistry and Diagnostics, University Hospital Hradec Kralove, Sokolska 581, 500 05 Hradec Kralove, Czech Republic
| | | | - Ondrej Soucek
- Department of Clinical Immunology and Allergology, University Hospital Hradec Kralove, Sokolska 581, 500 05 Hradec Kralove, Czech Republic;
| | - Milan Kostal
- 4th Department of Internal Medicine—Hematology, University Hospital Hradec Kralove, Sokolska 581, 500 05 Hradec Kralove, Czech Republic;
| | - Vit Rehacek
- Transfusion Department, University Hospital Hradec Kralove, Sokolska 581, 500 05 Hradec Kralove, Czech Republic;
| | - Lenka Kujovska Krcmova
- Department of Analytical Chemistry, Faculty of Pharmacy in Hradec Kralove, Charles University, Akademika Heyrovskeho 1203/8, 500 05 Hradec Kralove, Czech Republic; (A.V.); (L.K.K.)
- Department of Clinical Biochemistry and Diagnostics, University Hospital Hradec Kralove, Sokolska 581, 500 05 Hradec Kralove, Czech Republic
| | - Erich Gnaiger
- Oroboros Instruments GmbH, Schoepfstrasse 18, A-6020 Innsbruck, Austria; (L.F.G.-S.); (E.G.)
- D.Swarovski Research Laboratory, Department of General and Transplant Surgery, Medical University of Innsbruck, Christoph-Probst-Platz 1, Innrain 52, A-6020 Innsbruck, Austria
| | - Ondrej Sobotka
- 3rd Department of Internal Medicine—Metabolic Care and Gerontology, University Hospital Hradec Kralove, Sokolska 581, 500 05 Hradec Kralove, Czech Republic
- Correspondence: ; Tel.: +420-495832243
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McCann MR, McHugh CE, Kirby M, Jennaro TS, Jones AE, Stringer KA, Puskarich MA. A Multivariate Metabolomics Method for Estimating Platelet Mitochondrial Oxygen Consumption Rates in Patients with Sepsis. Metabolites 2020; 10:E139. [PMID: 32252461 PMCID: PMC7240966 DOI: 10.3390/metabo10040139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 03/27/2020] [Accepted: 03/31/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Sepsis-induced alterations in mitochondrial function contribute to organ dysfunction and mortality. Measuring mitochondrial function in vital organs is neither feasible nor practical, highlighting the need for non-invasive approaches. Mitochondrial function may be reflected in the concentrations of metabolites found in platelets and whole blood (WB) samples. We proposed to use these as alternates to indirectly estimate platelet mitochondrial oxygen consumption rate (mOCR) in sepsis patients. METHODS We determined the relationships between platelet mOCR and metabolites in both platelets and WB, as measured by quantitative 1H-NMR metabolomics. The associations were identified by building multiple linear regression models with stepwise forward-backward variable selection. We considered the models to be significant with an ANOVA test (p-value ≤ 0.05) and a positive predicted-R2. RESULTS The differences in adjusted-R2 and ANOVA p-values (platelet adj-R2: 0.836 (0.0003), 0.711 (0.0004) vs. WB adj-R2: 0.428 (0.0079)) from the significant models indicate the platelet models were more associated with platelet mOCR. CONCLUSIONS Our data suggest there are groups of metabolites in WB (leucine, acetylcarnitine) and platelets (creatine, ADP, glucose, taurine) that are associated with platelet mOCR. Thus, WB and platelet metabolites could be used to estimate platelet mOCR.
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Affiliation(s)
- Marc R. McCann
- The NMR Metabolomics Laboratory, Department of Clinical Pharmacy, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA; (M.R.M.); (C.E.M.); (T.S.J.); (K.A.S.)
| | - Cora E. McHugh
- The NMR Metabolomics Laboratory, Department of Clinical Pharmacy, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA; (M.R.M.); (C.E.M.); (T.S.J.); (K.A.S.)
| | - Maggie Kirby
- Department of Emergency Medicine, University of Mississippi Medical Center, Jackson, MS 39216, USA; (M.K.); (A.E.J.)
| | - Theodore S. Jennaro
- The NMR Metabolomics Laboratory, Department of Clinical Pharmacy, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA; (M.R.M.); (C.E.M.); (T.S.J.); (K.A.S.)
| | - Alan E. Jones
- Department of Emergency Medicine, University of Mississippi Medical Center, Jackson, MS 39216, USA; (M.K.); (A.E.J.)
| | - Kathleen A. Stringer
- The NMR Metabolomics Laboratory, Department of Clinical Pharmacy, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA; (M.R.M.); (C.E.M.); (T.S.J.); (K.A.S.)
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, School of Medicine, University of Michigan, Ann Arbor, MI 48109, USA
- Michigan Center for Integrative Research in Critical Care, University of Michigan, Ann Arbor, MI 48109, USA
| | - Michael A. Puskarich
- Department of Emergency Medicine, University of Minnesota, Minneapolis, MN 55455, USA
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Holper L, Ben-Shachar D, Mann JJ. Multivariate meta-analyses of mitochondrial complex I and IV in major depressive disorder, bipolar disorder, schizophrenia, Alzheimer disease, and Parkinson disease. Neuropsychopharmacology 2019; 44:837-849. [PMID: 29855563 PMCID: PMC6461987 DOI: 10.1038/s41386-018-0090-0] [Citation(s) in RCA: 121] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 04/26/2018] [Accepted: 05/07/2018] [Indexed: 12/17/2022]
Abstract
Complex I (NADH dehydrogenase, NDU) and complex IV (cytochrome-c-oxidase, COX) of the mitochondrial electron transport chain have been implicated in the pathophysiology of major psychiatric disorders, such as major depressive disorder (MDD), bipolar disorder (BD), and schizophrenia (SZ), as well as in neurodegenerative disorders, such as Alzheimer disease (AD) and Parkinson disease (PD). We conducted meta-analyses comparing complex I and IV in each disorder MDD, BD, SZ, AD, and PD, as well as in normal aging. The electronic databases Pubmed, EMBASE, CENTRAL, and Google Scholar, were searched for studies published between 1980 and 2018. Of 2049 screened studies, 125 articles were eligible for the meta-analyses. Complex I and IV were assessed in peripheral blood, muscle biopsy, or postmortem brain at the level of enzyme activity or subunits. Separate meta-analyses of mood disorder studies, MDD and BD, revealed moderate effect sizes for similar abnormality patterns in the expression of complex I with SZ in frontal cortex, cerebellum and striatum, whereas evidence for complex IV alterations was low. By contrast, the neurodegenerative disorders, AD and PD, showed strong effect sizes for shared deficits in complex I and IV, such as in peripheral blood, frontal cortex, cerebellum, and substantia nigra. Beyond the diseased state, there was an age-related robust decline in both complexes I and IV. In summary, the strongest support for a role for complex I and/or IV deficits, is in the pathophysiology of PD and AD, and evidence is less robust for MDD, BD, or SZ.
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Affiliation(s)
- L Holper
- Division of Molecular Imaging and Neuropathology, Columbia University and New York State Psychiatric Institute, New York, NY, USA.
| | - D Ben-Shachar
- Laboratory of Psychobiology, Department of Psychiatry, Rambam Health Care Campus, Rappaport Faculty of Medicine, Technion IIT, Haifa, Israel
| | - J J Mann
- Division of Molecular Imaging and Neuropathology, Columbia University and New York State Psychiatric Institute, New York, NY, USA
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Vevera J, Fišar Z, Nekovářová T, Vrablík M, Zlatohlávek L, Hroudová J, Singh N, Raboch J, Valeš K. Statin-induced changes in mitochondrial respiration in blood platelets in rats and human with dyslipidemia. Physiol Res 2016; 65:777-788. [PMID: 27429121 DOI: 10.33549/physiolres.933264] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) are widely used drugs for lowering blood lipid levels and preventing cardiovascular diseases. However, statins can have serious adverse effects, which may be related to development of mitochondrial dysfunctions. The aim of study was to demonstrate the in vivo effect of high and therapeutic doses of statins on mitochondrial respiration in blood platelets. Model approach was used in the study. Simvastatin was administered to rats at a high dose for 4 weeks. Humans were treated with therapeutic doses of rosuvastatin or atorvastatin for 6 weeks. Platelet mitochondrial respiration was measured using high-resolution respirometry. In rats, a significantly lower physiological respiratory rate was found in intact platelets of simvastatin-treated rats compared to controls. In humans, no significant changes in mitochondrial respiration were detected in intact platelets; however, decreased complex I-linked respiration was observed after statin treatment in permeabilized platelets. We propose that the small in vivo effect of statins on platelet energy metabolism can be attributed to drug effects on complex I of the electron transport system. Both intact and permeabilized platelets can be used as a readily available biological model to study changes in cellular energy metabolism in patients treated with statins.
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Affiliation(s)
- J Vevera
- Department of Psychiatry, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, Czech Republic.
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Abstract
SIGNIFICANCE The molecular mechanism of aging is still vigorously debated, although a general consensus exists that mitochondria are significantly involved in this process. However, the previously postulated role of mitochondrial-derived reactive oxygen species (ROS) as the damaging agents inducing functional loss in aging has fallen out of favor in the recent past. In this review, we critically examine the role of ROS in aging in the light of recent advances on the relationship between mitochondrial structure and function. RECENT ADVANCES The functional mitochondrial respiratory chain is now recognized as a reflection of the dynamic association of respiratory complexes in the form of supercomplexes (SCs). Besides providing kinetic advantage (channeling), SCs control ROS generation by the respiratory chain, thus providing a means to regulate ROS levels in the cell. Depending on their concentration, these ROS are either physiological signals essential for the life of the cell or toxic species that damage cell structure and functions. CRITICAL ISSUES We propose that under physiological conditions the dynamic nature of SCs reversibly controls the generation of ROS as signals involved in mitochondrial-nuclear communication. During aging, there is a progressive loss of control of ROS generation so that their production is irreversibly enhanced, inducing a vicious circle in which signaling is altered and structural damage takes place. FUTURE DIRECTIONS A better understanding on the forces affecting SC association would allow the manipulation of ROS generation, directing these species to their physiological signaling role.
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Affiliation(s)
- Maria Luisa Genova
- Dipartimento di Scienze Biomediche e Neuromotorie, Alma Mater Studiorum-Università di Bologna , Bologna, Italy
| | - Giorgio Lenaz
- Dipartimento di Scienze Biomediche e Neuromotorie, Alma Mater Studiorum-Università di Bologna , Bologna, Italy
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Mitochondrial changes in platelets are not related to those in skeletal muscle during human septic shock. PLoS One 2014; 9:e96205. [PMID: 24787741 PMCID: PMC4006866 DOI: 10.1371/journal.pone.0096205] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 04/04/2014] [Indexed: 12/22/2022] Open
Abstract
Platelets can serve as general markers of mitochondrial (dys)function during several human diseases. Whether this holds true even during sepsis is unknown. Using spectrophotometry, we measured mitochondrial respiratory chain biochemistry in platelets and triceps brachii muscle of thirty patients with septic shock (within 24 hours from admission to Intensive Care) and ten surgical controls (during surgery). Results were expressed relative to citrate synthase (CS) activity, a marker of mitochondrial density. Patients with septic shock had lower nicotinamide adenine dinucleotide dehydrogenase (NADH)/CS (p = 0.015), complex I/CS (p = 0.018), complex I and III/CS (p<0.001) and complex IV/CS (p = 0.012) activities in platelets but higher complex I/CS activity (p = 0.021) in triceps brachii muscle than controls. Overall, NADH/CS (r2 = 0.00; p = 0.683) complex I/CS (r2 = 0.05; p = 0.173), complex I and III/CS (r2 = 0.01; p = 0.485), succinate dehydrogenase (SDH)/CS (r2 = 0.00; p = 0.884), complex II and III/CS (r2 = 0.00; p = 0.927) and complex IV/CS (r2 = 0.00; p = 0.906) activities in platelets were not associated with those in triceps brachii muscle. In conclusion, several respiratory chain enzymes were variably inhibited in platelets, but not in triceps brachii muscle, of patients with septic shock. Sepsis-induced mitochondrial changes in platelets do not reflect those in other organs.
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Sjövall F, Ehinger JKH, Marelsson SE, Morota S, Frostner EA, Uchino H, Lundgren J, Arnbjörnsson E, Hansson MJ, Fellman V, Elmér E. Mitochondrial respiration in human viable platelets--methodology and influence of gender, age and storage. Mitochondrion 2012; 13:7-14. [PMID: 23164798 DOI: 10.1016/j.mito.2012.11.001] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 09/25/2012] [Accepted: 11/07/2012] [Indexed: 12/23/2022]
Abstract
Studying whole cell preparations with intact mitochondria and respiratory complexes has a clear benefit compared to isolated or disrupted mitochondria due to the dynamic interplay between mitochondria and other cellular compartments. Platelet mitochondria have a potential to serve as a source of human viable mitochondria when studying mitochondrial physiology and pathogenic mechanisms, as well as for the diagnostics of mitochondrial diseases. The objective of the present study was to perform a detailed evaluation of platelet mitochondrial respiration using high-resolution respirometry. Further, we aimed to explore the limits of sample size and the impact of storage as well as to establish a wide range of reference data from different pediatric and adult cohorts. Our results indicate that platelet mitochondria are well suited for ex-vivo analysis with the need for minute sample amounts and excellent reproducibility and stability.
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Affiliation(s)
- Fredrik Sjövall
- Mitochondrial Pathophysiology Unit, Lund University, 221 84 Lund, Sweden.
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Shrivastava M, Das TK, Behari M, Pati U, Vivekanandhan S. Ultrastructural variations in platelets and platelet mitochondria: a novel feature in amyotrophic lateral sclerosis. Ultrastruct Pathol 2011; 35:52-9. [PMID: 21299344 DOI: 10.3109/01913123.2010.541985] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Platelets are characterized as a systemic tool to elucidate mitochondria-allied perturbance in neurological diseases. The authors studied ultrastructural changes in platelets and platelet mitochondria using a case-control approach in amyotrophic lateral sclerosis (ALS). Subjects were sporadic ALS cases (n = 22) and age- and sex-matched controls (n = 16). Phlebotomy was performed, platelet concentrates (PCs) were prepared, and mitochondria were extracted. PCs and mitochondria were processed for ultrastructure study using transmission electron microscopy. Image analysis was done using Image-J. Transmission electron microscopy demonstrated both qualitative and quantitative variations in ALS platelets and platelet mitochondria. Heterogeneous distribution of granules, formation of vacuoles, blebs, pseudopodia, loose demarcation of cell membrane with a significant increase in area (20.3%), perimeter (17.82%), integrated density (21.44%), electron-lucent granules (41.79%), and vacuoles (36.58%) were observed in ALS platelets. Conversely, control platelets exhibited an increase of circularity (11.7%) and electron-dense granules (36.89%). In parallel, nonuniformity of matrix, faint cristae, greater lysosomal bodies, and lesser intramitochondrial granules were seen in ALS platelet mitochondria. Significantly greater area (26.88%), perimeter (15%), circularity (3.76%), and integrated density (25.18%) were observed in control platelet mitochondria. Ultastructural divergence in platelets of ALS patients underlines a potential dependence of platelets on modest mitochondrial functioning. These observations also support the view that systemic involvement might be a novel feature in ALS pathophysiology.
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Affiliation(s)
- Mohita Shrivastava
- Department of Neurobiochemistry, All India Institute of Medical Sciences, New Delhi, India
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12
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Sjövall F, Morota S, Hansson MJ, Friberg H, Gnaiger E, Elmér E. Temporal increase of platelet mitochondrial respiration is negatively associated with clinical outcome in patients with sepsis. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2010; 14:R214. [PMID: 21106065 PMCID: PMC3219983 DOI: 10.1186/cc9337] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Revised: 11/18/2010] [Accepted: 11/24/2010] [Indexed: 02/08/2023]
Abstract
Introduction Mitochondrial dysfunction has been suggested as a contributing factor to the pathogenesis of sepsis-induced multiple organ failure. Also, restoration of mitochondrial function, known as mitochondrial biogenesis, has been implicated as a key factor for the recovery of organ function in patients with sepsis. Here we investigated temporal changes in platelet mitochondrial respiratory function in patients with sepsis during the first week after disease onset. Methods Platelets were isolated from blood samples taken from 18 patients with severe sepsis or septic shock within 48 hours of their admission to the intensive care unit. Subsequent samples were taken on Day 3 to 4 and Day 6 to 7. Eighteen healthy blood donors served as controls. Platelet mitochondrial function was analyzed by high-resolution respirometry. Endogenous respiration of viable, intact platelets suspended in their own plasma or phosphate-buffered saline (PBS) glucose was determined. Further, in order to investigate the role of different dehydrogenases and respiratory complexes as well as to evaluate maximal respiratory activity of the mitochondria, platelets were permeabilized and stimulated with complex-specific substrates and inhibitors. Results Platelets suspended in their own septic plasma exhibited increased basal non-phosphorylating respiration (state 4) compared to controls and to platelets suspended in PBS glucose. In parallel, there was a substantial increase in respiratory capacity of the electron transfer system from Day 1 to 2 to Day 6 to 7 as well as compared to controls in both intact and permeabilized platelets oxidizing Complex I and/or II-linked substrates. No inhibition of respiratory complexes was detected in septic patients compared to controls. Non-survivors, at 90 days, had a more elevated respiratory capacity at Day 6 to 7 as compared to survivors. Cytochrome c increased over the time interval studied but no change in mitochondrial DNA was detected. Conclusions The results indicate the presence of a soluble plasma factor in the initial stage of sepsis inducing uncoupling of platelet mitochondria without inhibition of the electron transfer system. The mitochondrial uncoupling was paralleled by a gradual and substantial increase in respiratory capacity. This may reflect a compensatory response to severe sepsis or septic shock, that was most pronounced in non-survivors, likely correlating to the severity of the septic insult.
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Affiliation(s)
- Fredrik Sjövall
- Mitochondrial Pathophysiology Unit, Laboratory for Experimental Brain Research, Department of Clinical Sciences, Lund University, Sölvegatan 17, SE-221 84, Lund, Sweden.
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Jayachandran M, Preston CC, Hunter LW, Jahangir A, Owen WG, Korach KS, Miller VM. Loss of estrogen receptor beta decreases mitochondrial energetic potential and increases thrombogenicity of platelets in aged female mice. AGE (DORDRECHT, NETHERLANDS) 2010; 32:109-121. [PMID: 19908165 PMCID: PMC2829645 DOI: 10.1007/s11357-009-9119-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Accepted: 10/15/2009] [Indexed: 05/28/2023]
Abstract
Platelets derived from aged (reproductively senescent) female mice with genetic deletion of estrogen receptor beta (betaER) are more thrombogenic than those from age-matched wild-type (WT) mice. Intracellular processes contributing to this increased thrombogenicity are not known. Experiments were designed to identify subcellular localization of estrogen receptors and evaluate both glycolytic and mitochondrial energetic processes which might affect platelet activation. Platelets and blood from aged (22-24 months) WT and estrogen receptor beta knockout (betaERKO) female mice were used in this study. Body, spleen weight, and serum concentrations of follicle-stimulating hormone and 17beta-estradiol were comparable between WT and betaERKO mice. Number of spontaneous deaths was greater in the betaERKO colony (50% compared to 30% in WT) over the course of 24 months. In resting (nonactivated) platelets, estrogen receptors did not appear to colocalize with mitochondria by immunostaining. Lactate production and mitochondrial membrane potential of intact platelets were similar in both groups of mice. However, activities of NADH dehydrogenase, cytochrome bc ( 1 ) complex, and cytochrome c oxidase of the electron transport chain were reduced in mitochondria isolated from platelets from betaERKO compared to WT mice. There were a significantly higher number of phosphatidylserine-expressing platelet-derived microvesicles in the plasma and a greater thrombin-generating capacity in betaERKO compared to WT mice. These results suggest that deficiencies in betaER affect energy metabolism of platelets resulting in greater production of circulating thrombogenic microvesicles and could potentially explain increased predisposition to thromboembolism in some elderly females.
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Affiliation(s)
- Muthuvel Jayachandran
- Department of Surgery, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN, 55905, USA,
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Ramanujan VK, Jo JA, Cantu G, Herman BA. Spatially resolved fluorescence lifetime mapping of enzyme kinetics in living cells. J Microsc 2008; 230:329-38. [PMID: 18503658 DOI: 10.1111/j.1365-2818.2008.01991.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Traditional cuvette-based enzyme studies lack spatial information and do not allow real-time monitoring of the effects of modulating enzyme functions in vivo. In order to probe the realistic timescales of steric modifications in enzyme-substrate complexes and functional binding-unbinding kinetics in living cells without losing spatial information, it is imperative to develop sensitive imaging strategies that can report enzyme kinetics in real time over a wide dynamic range of timescales. Here we present a multi-photon excitation-based, ultra-fast photon detection using a streak camera and Laguerre expansion-based fast deconvolution approach for achieving high spatio-temporal resolution in monitoring real-time enzyme kinetics in single cells. In particular, we report spatially resolved, nanosecond-scale fluorescence dynamics associated with binding-unbinding kinetics of endogenous metabolic co-factor nicotinamide adenine dinucleotide with enzymes in intact living cells. By monitoring real-time kinetics of NAD(P)H-enzyme kinetics in primary hepatocytes isolated from young and aged mouse models, we observed that the mechanism of inhibition of mitochondrial respiration at complex I site is mediated by redistribution of free and protein-bound nicotinamide adenine dinucleotide pools and that this equilibrium redistribution is affected by age-related modifications in mitochondrial function. We describe unique advantages of Laguerre deconvolution algorithm in comparison with conventional lifetime analysis approaches. Non-invasive monitoring of metabolic dysfunctions in intact animal models is an attractive strategy for gaining insight into the dynamics of tissue metabolism in health and in various metabolic syndromes such as cancer, diabetes and aging-induced metabolic dysfunctions. Besides the example demonstrated above, we envisage that the proposed method can find applications in a variety of other situations where intensity-based approaches fall short owing to spectroscopic artefacts.
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Affiliation(s)
- V K Ramanujan
- Department of Cellular and Structural Biology, University of Texas Health Science, Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA.
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15
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Shi C, Guo K, Yew DT, Yao Z, Forster EL, Wang H, Xu J. Effects of ageing and Alzheimer's disease on mitochondrial function of human platelets. Exp Gerontol 2008; 43:589-94. [PMID: 18359596 DOI: 10.1016/j.exger.2008.02.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Revised: 02/06/2008] [Accepted: 02/07/2008] [Indexed: 12/23/2022]
Abstract
Mitochondrial dysfunction may play an important role in the pathogenesis of ageing and age-neurodegenerative diseases such as Alzheimer's disease (AD). Platelet mitochondrial membrane potential (reflected by measurement of JC-1 fluorescence ratio) and adenosine 5'-triphosphate (ATP) contents of 24 moderate probable AD patients, 20 age-matched control subjects and 20 young control subjects were measured. Also, a beta-amyloid peptide (Abeta)-induced damage model of platelets was established. After the addition of Abeta, platelet JC-1 fluorescence ratio and ATP content of platelets were measured in 16 AD patients, 20 aged and 20 young control subjects. Young control subjects had higher JC-1 fluorescence ratio than both AD patients and aged control subjects. No significant differences in platelet ATP contents were found among AD patients, aged and young control subjects. After the addition of Abeta, platelet JC-1 fluorescence ratio and ATP content of aged and young control subjects lowered markedly, but no obvious decrease of platelet JC-1 fluorescence ratio of AD patients was found compared with those of aged and young control subjects. Decrease of platelet JC-1 fluorescence ratio of aged control subjects was lower than that of young control subjects following the addition of Abeta. These results indicated that mitochondrial dysfunction may occur during ageing and platelet mitochondria of AD patients and aged subjects showed a tolerance to Abeta-induced damage. Therefore, blood platelets might serve as a biomarker for detection of mitochondrial function and age-related disease.
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Affiliation(s)
- Chun Shi
- Department of Anatomy, Zhongshan School of Medicine, Sun Yat-Sen University Guangzhou, Guangdong 510080, China
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16
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Xu J, Shi C, Li Q, Lam WP, Wai MSM, Yew DT. Effects of beta-amyloid peptide and estrogen on platelet mitochondrial function of Sprague-Dawley rats. Platelets 2007; 18:460-8. [PMID: 17763155 DOI: 10.1080/09537100701206808] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Beta-amyloid peptide (Abeta) peptides play a central role in the development of Alzheimer's disease. They are known to induce mitochondrial dysfunction and caspase activation, resulting in apoptosis of neuronal cells. In the present experiment, an Abeta-induced damage model of platelets was established to observe the effects of Abeta, estradiol benzoate (EB) and genistein on platelets and platelet mitochondria. It was found that after the addition of Abeta, platelet number, platelet mitochondrial membrane potential (DeltaPsim) and adenosine triphosphate (ATP) content were lowered while no protective effects of EB and genistein had been observed. The platelets could serve as a biomarker for detection of mitochondrial function and age related disease.
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Affiliation(s)
- Jie Xu
- Department of Anatomy, Zhongshan School of Medicine, Sun Yat-Sen University Guangzhou, Guangdong 510080, China
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17
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Xu J, Shi C, Li Q, Wu J, Forster EL, Yew DT. Mitochondrial dysfunction in platelets and hippocampi of senescence-accelerated mice. J Bioenerg Biomembr 2007; 39:195-202. [PMID: 17436064 DOI: 10.1007/s10863-007-9077-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2007] [Accepted: 03/12/2007] [Indexed: 12/22/2022]
Abstract
Senescence-accelerated mice (SAM) strains are useful models to understand the mechanisms of age-dependent degeneration. In this study, measurements of the mitochondrial membrane potential (Deltapsi(m)) of platelets and the Adenosine 5(')-triphosphate (ATP) content of hippocampi and platelets were made, and platelet mitochondria were observed in SAMP8 (faster aging mice) and SAMR1 (aging resistant control mice) at 2, 6 and 9 months of age. In addition, an Abeta-induced (Amyloid beta-protein) damage model of platelets was established. After the addition of Abeta, the Deltapsi(m) of platelets of SAMP8 at 1 and 6 months of age were measured. We found that platelet Deltapsi(m), and hippocampal and platelet ATP content of SAMP8 mice decreased at a relatively early age compared with SAMR1. The platelets of 6 month-old SAMP8 showed a tolerance to Abeta-induced damages. These results suggest that mitochondrial dysfunction might be one of the mechanisms leading to age-associated degeneration in SAMP mice at an early age and the platelets could serve as a biomarker for detection of mitochondrial function and age related disease.
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Affiliation(s)
- Jie Xu
- Department of Anatomy, Zhongshan School of Medicine, Sun Yat-Sen University Guangzhou, Guangdong 510080, China
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18
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Pallotti F, Lenaz G. Isolation and Subfractionation of Mitochondria from Animal Cells and Tissue Culture Lines. Methods Cell Biol 2007; 80:3-44. [PMID: 17445687 DOI: 10.1016/s0091-679x(06)80001-4] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Francesco Pallotti
- Dipartimento di Scienze Biomediche Sperimentali e Cliniche, Università degli Studi dell'Insubria, 21100 Varese, Italy
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19
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Lenaz G, Baracca A, Fato R, Genova ML, Solaini G. New insights into structure and function of mitochondria and their role in aging and disease. Antioxid Redox Signal 2006; 8:417-37. [PMID: 16677088 DOI: 10.1089/ars.2006.8.417] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
This review covers some novel findings on mitochondrial biochemistry and discusses diseases due to mitochondrial DNA mutations as a model of the changes occurring during physiological aging. The random collision model of organization of the mitochondrial respiratory chain has been recently challenged on the basis of findings of supramolecular organization of respiratory chain complexes. The source of superoxide in Complex I is discussed on the basis of laboratory experiments using a series of specific inhibitors and is presumably iron sulfur center N2. Maternally inherited diseases due to mutations of structural genes in mitochondrial DNA are surveyed as a model of alterations mimicking those occurring during normal aging. The molecular defects in senescence are surveyed on the basis of the "Mitochondrial Theory of Aging", establishing mitochondrial DNA somatic mutations, caused by accumulation of oxygen radical damage, to be at the basis of cellular senescence. Mitochondrial production of reactive oxygen species increases with aging and mitochondrial DNA mutations and deletions accumulate and may be responsible for oxidative phosphorylation defects. Evidence is presented favoring the mitochondrial theory, with primary mitochondrial alterations, although the problem is made more complex by changes in the cross-talk between nuclear and mitochondrial DNA.
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Affiliation(s)
- Giorgio Lenaz
- Dipartimento di Biochimica, Università di Bologna, Bologna, Italy.
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20
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Phinney AL, Andringa G, Bol JGJM, Wolters EC, van Muiswinkel FL, van Dam AMW, Drukarch B. Enhanced sensitivity of dopaminergic neurons to rotenone-induced toxicity with aging. Parkinsonism Relat Disord 2006; 12:228-38. [PMID: 16488175 DOI: 10.1016/j.parkreldis.2005.12.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2005] [Accepted: 12/14/2005] [Indexed: 12/21/2022]
Abstract
Rotenone has been reported to induce various degrees of Parkinsonism in rats. We tested whether advancing age alters the sensitivity of dopaminergic neurons to rotenone. A low, systemic dose of rotenone had no effect on young rats, but led to a 20-30% reduction of tyrosine hydroxylase-positive neurons in the substantia nigra of older rats. The effect was specific to nigral dopaminergic neurons and may be associated with the increase of glial cell activation in older rats. These data suggest that age enhances the sensitivity of dopaminergic neurons to rotenone and should be considered when assessing models of Parkinson's disease.
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Affiliation(s)
- Amie L Phinney
- Department of Medical Pharmacology, Institute for Clinical and Experimental Neurosciences, VU University Medical Center, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands
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21
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Müftüoglu M, Elibol B, Dalmizrak O, Ercan A, Kulaksiz G, Ogüs H, Dalkara T, Ozer N. Mitochondrial complex I and IV activities in leukocytes from patients with parkin mutations. Mov Disord 2004; 19:544-8. [PMID: 15133818 DOI: 10.1002/mds.10695] [Citation(s) in RCA: 158] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The parkin protein functions as a RING-type ubiquitin protein ligase. Considering the possibility that impaired ubiquitin-proteosomal system activity may impair antioxidant defenses and enhance oxidative stress, we have investigated the activity of mitochondrial respiratory enzymes in patients with parkin gene mutations. A significant decrease in the leukocyte complex I activity was found both in patients with parkin mutations (62.5%) and idiopathic PD (64.5%) compared with age-matched controls (P < 0.001). Complex IV activity was also decreased significantly in idiopathic PD patients (60%), but no difference was detected between controls and patients with parkin mutations.
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Affiliation(s)
- Meltem Müftüoglu
- Department of Biochemistry, Hacettepe University, Faculty of Medicine, Ankara, Turkey
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22
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Affiliation(s)
- Giorgio Lenaz
- Dipartimento Di Biochemica, Universita Di Bologna, Italy
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23
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GENOVA MARIALUISA, PICH MILENAMERLO, BERNACCHIA ANDREA, BIANCHI CRISTINA, BIONDI ANNALISA, BOVINA CARLA, FALASCA ANNAIDA, FORMIGGINI GABRIELLA, CASTELLI GIOVANNAPARENTI, LENAZ GIORGIO. The Mitochondrial Production of Reactive Oxygen Species in Relation to Aging and Pathology. Ann N Y Acad Sci 2004. [DOI: 10.1196/annals.1293.010] [Citation(s) in RCA: 167] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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24
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Genova ML, Pich MM, Bernacchia A, Bianchi C, Biondi A, Bovina C, Falasca AI, Formiggini G, Castelli GP, Lenaz G. The mitochondrial production of reactive oxygen species in relation to aging and pathology. Ann N Y Acad Sci 2004; 1011:86-100. [PMID: 15126287 DOI: 10.1007/978-3-662-41088-2_10] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Mitochondria are known to be strong producers of reactive oxygen species (ROS) and, at the same time, particularly susceptible to the oxidative damage produced by their action on lipids, proteins, and DNA. In particular, damage to mtDNA induces alterations to the polypeptides encoded by mtDNA in the respiratory complexes, with consequent decrease of electron transfer, leading to further production of ROS and thus establishing a vicious circle of oxidative stress and energetic decline. This deficiency in mitochondrial energetic capacity is considered the cause of aging and age-related degenerative diseases. Complex I would be the enzyme most affected by ROS, since it contains seven of the 13 subunits encoded by mtDNA. Accordingly, we found that complex I activity is significantly affected by aging in rat brain and liver mitochondria as well as in human platelets. Moreover, due to its rate control over aerobic respiration, such alterations are reflected on the entire oxidative phosphorylation system. We also investigated the role of mitochondrial complex I in superoxide production and found that the one-electron donor to oxygen is most probably the Fe-S cluster N2. Short chain coenzyme Q (CoQ) analogues enhance ROS formation, presumably by mediating electron transfer from N2 to oxygen, both in bovine heart SMP and in cultured HL60 cells. Nevertheless, we have accumulated much evidence of the antioxidant role of reduced CoQ(10) in several cellular systems and demonstrated the importance of DT-diaphorase and other internal cellular reductases to reduce exogenous CoQ(10) after incorporation.
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Affiliation(s)
- Maria Luisa Genova
- Dipartimento di Biochimica "G. Moruzzi," University of Bologna, 40126 Bologna, Italy
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25
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Merlo Pich M, Raule N, Catani L, Fagioli ME, Faenza I, Cocco L, Lenaz G. Increased transcription of mitochondrial genes for Complex I in human platelets during ageing. FEBS Lett 2004; 558:19-22. [PMID: 14759509 DOI: 10.1016/s0014-5793(03)01520-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2003] [Revised: 08/29/2003] [Accepted: 12/23/2003] [Indexed: 10/26/2022]
Abstract
We studied the effect of ageing on the mRNA levels of mitochondria-encoded polypeptides in human platelets. We used quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) to investigate the expression of selected cytochrome c oxidase (COX) genes (subunits I and III) and Complex I genes (subunits reduced nicotinamide adenine dinucleotide (NADH) dehydrogenase (ND)1 and (ND)5 in platelets from young and aged healthy subjects. Northern blot analysis confirmed the PCR results. COX I expression is higher than that of COX III in both young and aged platelets. A significant increase of transcripts for Complex I was found during ageing. On the contrary, the mRNA levels of the two COX subunits did not significantly vary during ageing.
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Affiliation(s)
- Milena Merlo Pich
- Department of Biochemistry 'G. Moruzzi', University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
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26
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Uyemura SA, Luo S, Vieira M, Moreno SNJ, Docampo R. Oxidative Phosphorylation and Rotenone-insensitive Malate- and NADH-Quinone Oxidoreductases in Plasmodium yoelii yoelii Mitochondria in Situ. J Biol Chem 2004; 279:385-93. [PMID: 14561763 DOI: 10.1074/jbc.m307264200] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Respiration, membrane potential, and oxidative phosphorylation of mitochondria of Plasmodium yoelii yoelii trophozoites were assayed in situ after permeabilization with digitonin. ADP induced an oligomycin-sensitive transition from resting to phosphorylating respiration in the presence of oxidizable substrates. A functional respiratory chain was demonstrated. In addition, the ability of the parasite to oxidize exogenous NADH, as well as the insensitivity of respiration to rotenone and its sensitivity to flavone, suggested the presence of an alternative NADH-quinone (NADH-Q) oxidoreductase. Rotenone-insensitive respiration and membrane potential generation in the presence of malate suggested the presence of a malate-quinone oxidoreductase. These results are in agreement with the presence of genes in P. yoelii encoding for proteins with homology to NADH-Q oxidoreductases of bacteria, plant, fungi, and protozoa and malate-quinone oxidoreductases of bacteria. The complete inhibition of respiration by antimycin A and cyanide excluded the presence of an alternative oxidase as described in other parasites. An uncoupling effect of fatty acids was partly reversed by bovine serum albumin and GTP but was unaffected by carboxyatractyloside. These results provide the first biochemical evidence of the presence of an alternative NADH-Q oxidoreductase and a malate-quinone oxidoreductase and confirm the operation of oxidative phosphorylation in malaria parasites.
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Affiliation(s)
- Sergio A Uyemura
- Laboratory of Molecular Parasitology, Department of Pathobiology and Center for Zoonoses Research, University of Illinois at Urbana-Champaign, Urbana, Illinois 61802, USA
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27
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Genova ML, Pich MM, Biondi A, Bernacchia A, Falasca A, Bovina C, Formiggini G, Parenti Castelli G, Lenaz G. Mitochondrial production of oxygen radical species and the role of Coenzyme Q as an antioxidant. Exp Biol Med (Maywood) 2003; 228:506-13. [PMID: 12709577 DOI: 10.1177/15353702-0322805-14] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The mitochondrial respiratory chain is a powerful source of reactive oxygen species (ROS), which is considered as the pathogenic agent of many diseases and of aging. We have investigated the role of complex I in superoxide radical production and found by the combined use of specific inhibitors of complex I that the one-electron donor to oxygen in the complex is a redox center located prior to the sites where three different types of Coenzyme Q (CoQ) competitors bind, to be identified with an Fe-S cluster, most probably N2, or possibly an ubisemiquinone intermediate insensitive to all the above inhibitors. Short-chain Coenzyme Q analogs enhance superoxide formation, presumably by mediating electron transfer from N2 to oxygen. The clinically used CoQ analog, idebenone, is particularly effective, raising doubts on its safety as a drug. Cells counteract oxidative stress by antioxidants. CoQ is the only lipophilic antioxidant to be biosynthesized. Exogenous CoQ, however, protects cells from oxidative stress by conversion into its reduced antioxidant form by cellular reductases. The plasma membrane oxidoreductase and DT-diaphorase are two such systems, likewise, they are overexpressed under oxidative stress conditions.
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Affiliation(s)
- Maria Luisa Genova
- Dipartimento di Biochimica "G Moruzzi", University of Bologna, 40126 Bologna, Italy
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28
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Lenaz G, Bovina C, D'Aurelio M, Fato R, Formiggini G, Genova ML, Giuliano G, Merlo Pich M, Paolucci U, Parenti Castelli G, Ventura B. Role of mitochondria in oxidative stress and aging. Ann N Y Acad Sci 2002; 959:199-213. [PMID: 11976197 DOI: 10.1111/j.1749-6632.2002.tb02094.x] [Citation(s) in RCA: 294] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The mitochondrial respiratory chain is a powerful source of reactive oxygen species (ROS), considered as the pathogenic agent of many diseases and of aging. We have investigated the role of Complex I in superoxide radical production and found by combined use of specific inhibitors of Complex I that the one-electron donor in the Complex to oxygen is a redox center located prior to the sites where three different types of coenzyme Q (CoQ) competitors bind, to be identified with an Fe-S cluster, most probably N2, or possibly an ubisemiquinone intermediate insensitive to all the above inhibitors. Short-chain coenzyme Q analogues enhance superoxide formation, presumably by mediating electron transfer from N2 to oxygen. The clinically used CoQ analogue idebenone is particularly effective, raising doubts about its safety as a drug. The mitochondrial theory of aging considers somatic mutations of mitochondrial DNA induced by ROS as the primary cause of energy decline; in rat liver mitochondria, Complex I appears to be most affected by aging and to become strongly rate limiting for electron transfer. Mitochondrial energetics is also deranged in human platelets upon aging, as demonstrated by the decreased Pasteur effect (enhancement of lactate production by respiratory inhibitors). Cells counteract oxidative stress by antioxidants: CoQ is the only lipophilic antioxidant to be biosynthesized. Exogenous CoQ, however, protects cells from oxidative stress by conversion into its reduced antioxidant form by cellular reductases. The plasma membrane oxidoreductase and DT-diaphorase are two such systems: likewise, they are overexpressed under oxidative stress conditions.
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Affiliation(s)
- Giorgio Lenaz
- Dipartimento di Biochimica G. Moruzzi, Università di Bologna, Via Irnerio 48, 40126 Bologna, Italy.
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29
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Ventura B, Genova ML, Bovina C, Formiggini G, Lenaz G. Control of oxidative phosphorylation by Complex I in rat liver mitochondria: implications for aging. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1553:249-60. [PMID: 11997134 DOI: 10.1016/s0005-2728(01)00246-8] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We compared NAD-dependent state 4 and state 3 respiration, NADH oxidation and Complex I specific activity in liver mitochondria from 4- and 30-month-old rats. All the activities examined were significantly decreased with aging. In both groups of animals, the flux control coefficients measured by rotenone titration indicated that Complex I is largely rate controlling upon NADH aerobic oxidation while, in state 3 respiration, it shares the control with other steps in the pathway. Moreover, we observed a trend wherein flux control coefficients of Complex I became higher with age. This indication was strengthened by examining the rotenone inhibition thresholds showing that Complex I becomes more rate controlling, over all the examined activities, during aging. Our results point out that age-related alterations of the mitochondrial functions are also present in tissues considered less prone to accumulate mitochondrial DNA mutations.
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Affiliation(s)
- Barbara Ventura
- Dipartimento di Biochimica G. Moruzzi, Università di Bologna, Via Irnerio 48, 40126, Bologna, Italy
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30
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Pallotti F, Lenaz G. Isolation and subfractionation of mitochondria from animal cells and tissue culture lines. Methods Cell Biol 2002; 65:1-35. [PMID: 11381588 DOI: 10.1016/s0091-679x(01)65002-7] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- F Pallotti
- Department of Neurology, Columbia University, New York, New York 10032, USA
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31
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Fang J, Wang Y, Beattie DS. Isolation and characterization of complex I, rotenone-sensitive NADH:ubiquinone oxidoreductase, from the procyclic forms ofTrypanosoma brucei. ACTA ACUST UNITED AC 2001; 268:3075-82. [PMID: 11358527 DOI: 10.1046/j.1432-1327.2001.02205.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Additional characterization of complex I, rotenone-sensitive NADH:ubiquinone oxidoreductase, in the mitochondria of Trypanosoma brucei brucei has been obtained. Both proline:cytochrome c reductase and NADH:ubiquinone oxidoreductase of procyclic T. brucei were inhibited by the specific inhibitors of complex I rotenone, piericidin A, and capsaicin. These inhibitors had no effect on succinate: cytochrome c reductase activity. Antimycin A, a specific inhibitor of the cytochrome bc1 complex (ubiquinol:cytochrome c oxidoreductase), blocked almost completely cytochrome c reductase activity with either proline or succinate as electron donor, but had no inhibitory effect on NADH:ubiquinone oxidoreductase activity. The rotenone-sensitive NADH:ubiquinone oxidoreductase of procyclic T. brucei was partially purified by sucrose density centrifugation of mitochondria solubilized with dodecyl-beta-D-maltoside, with an approximately eightfold increase in specific activity compared to that of the mitochondrial membranes. Four polypeptides of the partially purified enzyme were identified as the homologous subunits of complex I (51 kDa, PSST, TYKY, and ND4) by immunoblotting with antibodies raised against subunits of Paracoccus denitrificans and against synthetic peptides predicted from putative complex I subunit genes encoded by mitochondrial and nuclear T. brucei DNA. Blue Native polyacrylamide gel electrophoresis of T. brucei mitochondrial membrane proteins followed by immunoblotting revealed the presence of a putative complex I with a molecular mass of 600 kDa, which contains a minimum of 11 polypeptides determined by second-dimensional Tricine-SDS/PAGE including the 51 kDa, PSST and TYKY subunits.
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Affiliation(s)
- J Fang
- Department of Biochemistry, West Virginia University School of Medicine, Morgantown, WV 26506-9142, USA
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32
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D'Aurelio M, Merlo Pich M, Catani L, Sgarbi GL, Bovina C, Formiggini G, Parenti Castelli G, Baum H, Tura S, Lenaz G. Decreased Pasteur effect in platelets of aged individuals. Mech Ageing Dev 2001; 122:823-33. [PMID: 11337011 DOI: 10.1016/s0047-6374(01)00239-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We have investigated the mitochondrial energy state in human platelets of young (19-30 years old) and aged individuals (65-87 years old) exploiting the Pasteur effect, i.e. stimulation of lactate production by incubation of the purified platelets with the mitochondrial respiratory chain inhibitor, antimycin A. This assay allows the determination of mitochondrial function with respect to glycolysis, and the ratio of mitochondrial adenosine triphosphate (ATP) to glycolytic ATP. A significant increase of basal, non-stimulated lactate production and decrease of the stimulation by antimycin A were observed in the older individuals, suggesting that the impairment of oxidative phosphorylation detectable in post-mitotic tissues of aged individuals can be observed also in easily collectable blood cells.
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Affiliation(s)
- M D'Aurelio
- Dipartimento di Biochimica G. Moruzzi, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
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33
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Lenaz G, D'Aurelio M, Merlo Pich M, Genova ML, Ventura B, Bovina C, Formiggini G, Parenti Castelli G. Mitochondrial bioenergetics in aging. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1459:397-404. [PMID: 11004456 DOI: 10.1016/s0005-2728(00)00177-8] [Citation(s) in RCA: 147] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Mitochondria are strongly involved in the production of reactive oxygen species, considered as the pathogenic agent of many diseases and of aging. The mitochondrial theory of aging considers somatic mutations of mitochondrial DNA induced by oxygen radicals as the primary cause of energy decline; experimentally, complex I appears to be mostly affected and to become strongly rate limiting for electron transfer. Mitochondrial bioenergetics is also deranged in human platelets upon aging, as shown by the decreased Pasteur effect (enhancement of lactate production by respiratory chain inhibition). Cells counteract oxidative stress by antioxidants; among lipophilic antioxidants, coenzyme Q is the only one of endogenous biosynthesis. Exogenous coenzyme Q, however, protects cells from oxidative stress by conversion into its reduced antioxidant form by cellular reductases.
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Affiliation(s)
- G Lenaz
- Dipartimento di Biochimica 'G. Moruzzi', Università di Bologna, Via Irnerio 48, 40126, Bologna, Italy.
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Drouet M, Lauthier F, Charmes JP, Sauvage P, Ratinaud MH. Age-associated changes in mitochondrial parameters on peripheral human lymphocytes. Exp Gerontol 1999; 34:843-52. [PMID: 10622419 DOI: 10.1016/s0531-5565(99)00058-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Among theories of aging, mitochondria are believed to be involved in senescence. Alterations of respiratory chain function and accumulation of various mitochondrial DNA mutations have been reported in mammalian postmitotic tissues. Because mitochondria have a central role in apoptosis and in adenosine triphosphate production, alteration of mitochondria function could contribute to immune senescence. We searched for alterations of mitochondrial parameters in peripheral lymphocytes with aging. Comparisons of respiratory chain activities of complex II+III, III, and IV were carried out in two populations of healthy volunteers with average ages of 35.3 +/- 6.7 years and 80.8 +/- 8.7 years. No difference was observed in complex IV activity between each group, whereas a significant decrease of complex II+III and a nonsignificant decrease of complex III activity were observed with aging. Alterations in mitochondrial functions can result from mutations in mitochondrial DNA (mtDNA), the most common being the 4977-bp deletion (mtDNA(-4977)). In either group we observed many deletions of mtDNA on peripheral blood lymphocytes by large-fragment polymerase chain reaction. This result suggests that alterations of respiratory chain activities observed with aging in lymphocytes could be the result of nuclear DNA dysfunction, with consequences on immune function (reduced responsiveness to antigen). Its possible implication on the recent observation of increased apoptosis of CD45RA+ RO- T cells with aging is discussed.
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Affiliation(s)
- M Drouet
- Equipe Postulante Centre National de la Recherche Scientifique 118, Faculté de Médecine, Limoges, France.
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35
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Martín-Valmaseda EM, Sánchez-Yagüe J, Rodríguez MC, Gómez FP, Llanillo M. Comparison between in vitro lipid peroxidation in fresh sheep platelets and peroxidative processes during sheep platelet ageing under storage at 4 degrees C. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1419:313-24. [PMID: 10407082 DOI: 10.1016/s0005-2736(99)00080-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Incubation of sheep platelet crude membranes with xanthine oxidase (XO)/hypoxanthine/Fe(2+)-ADP revealed: (i) a fast peroxidative response - with a maximal linear rate of 14 nmol malondialdehyde (MDA) equivalents/mg protein, as evidenced by the thiobarbituric acid test - and a decrease in the polyunsaturated fatty acid (PUFA) content of the platelet crude membranes; (ii) a decrease in the lipid fluidity in the deep lipid core of the membranes but not at the membrane surface; (iii) a dramatic inhibitory effect on glucose 6-phosphatase (Glc-6-Pase) but not on acetylcholinesterase activity. Platelets were also aged by storage at 4 degrees C in their own plasma or in Seto additive solution. In these media, platelet aggregates were visible and the effects on platelet phospholipids, PUFA, lipid extract fluorescence, crude membrane fluidity and membrane-bound enzyme activities were assessed for comparison with those observed in in vitro lipid peroxidation. The sensitivity of membranes from stored platelets to lipid peroxidation was also assessed. Storage of platelets in plasma for 5 days was associated with different changes in their crude membranes such as decreases in arachidonic acid contents, the decrease not being avoided by the presence of phospholipase A(2) inhibitors, increases in MDA equivalents, conjugated dienes and lipid extract fluorescence, decreases in the amounts of MDA equivalents formed by platelet crude membranes treated with the oxidizing agents, changes in membrane fluidity and inhibition of Glc-6-Pase. All these alterations were less pronounced or even abolished after platelet storage in Seto. These findings suggest that platelet lipid peroxidation due to XO/hypoxanthine/Fe(2+)-ADP and platelet membrane alterations observed after platelet ageing under storage at 4 degrees C share common features. Also, as regards the prevention of peroxidative processes, Seto solution permits better storage of sheep platelets than plasma.
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Affiliation(s)
- E M Martín-Valmaseda
- Departamento de Bioquímica y Biología Molecular, Universidad de Salamanca, Edificio Departamental, Lab. 106, Plaza Doctores de la Reina s/n, E-37007, Salamanca, Spain
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36
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Abstract
Mitochondria are deeply involved in the production of reactive oxygen species through one-electron carriers in the respiratory chain; mitochondrial structures are also very susceptible to oxidative stress as evidenced by massive information on lipid peroxidation, protein oxidation, and mitochondrial DNA (mtDNA) mutations. Oxidative stress can induce apoptotic death, and mitochondria have a central role in this and other types of apoptosis, since cytochrome c release in the cytoplasm and opening of the permeability transition pore are important events in the apoptotic cascade. The discovery that mtDNA mutations are at the basis of a number of human pathologies has profound implications: maternal inheritance of mtDNA is the basis of hereditary mitochondrial cytopathies; accumulation of somatic mutations of mtDNA with age has represented the basis of the mitochondrial theory of ageing, by which a vicious circle is established of mtDNA damage, altered oxidative phosphorylation and overproduction of reactive oxygen species. Experimental evidence of respiratory chain defects and of accumulation of multiple mtDNA deletions with ageing is in accordance with the mitochondrial theory, although some other experimental findings are not directly ascribable to its postulates.
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Affiliation(s)
- G Lenaz
- Dipartimento di Biochimica, Università di Bologna, Via Irnerio 48, 40126 Bologna, Italy.
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37
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Abstract
This review considers the interaction of Complex I with different redox acceptors, mainly homologs and analogs of the physiological acceptor, hydrophobic Coenzyme Q. After examining the physical properties of the different quinones and their efficacy in restoring mitochondrial respiration, a survey ensues of the advantages and drawbacks of the quinones commonly used in Complex I activity determination and of their kinetic properties. The available evidence is then displayed on structure-activity relationships of various quinone compounds in terms of electron transfer activity and proton translocation, and the present knowledge is discussed in terms of the nature of multiple quinone-binding sites in the Complex.
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Affiliation(s)
- G Lenaz
- Dipartimento di Biochimica 'G. Moruzzi', University of Bologna, Via Irnerio 48, 40126 Bologna, Italy.
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Biagini G, Pallotti F, Carraro S, Sgarbi G, Pich MM, Lenaz G, Anzivino F, Gualandi G, Xin D. Mitochondrial DNA in platelets from aged subjects. Mech Ageing Dev 1998; 101:269-75. [PMID: 9622230 DOI: 10.1016/s0047-6374(97)00181-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This study aimed to assess platelets as a possible model for screening the accumulation of mitochondrial DNA mutations, particularly during normal ageing. For this purpose we isolated platelets from young and old donors selected by lack of systemic and haematological diseases. We studied the accumulation of a particular deletion (4977-bp deletion) that usually accumulates in an age-related manner in different post-mitotic tissues, such as brain, heart and skeletal muscle, and in some non-post-mitotic tissues (skin, liver). Using different primers, we failed to detect this particular species of deletion in platelets both from young and old individuals. However, we cannot exclude the presence of other species of deletions or point mutations affecting the mitochondrial DNA in platelets during the aging process.
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Affiliation(s)
- G Biagini
- Istituto di Morfologia Umana Normale, Università di Ancona, Torrette di Ancona, Italy
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Pallotti F, Genova M, Pich M, Zucchini C, Carraro S, Tesei M, Bovina C, Lenaz G. Mitochondrial dysfunction and brain disorders. Arch Gerontol Geriatr 1998. [DOI: 10.1016/s0167-4943(98)80056-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Lenaz G, Cavazzoni M, Genova ML, D'Aurelio M, Merlo Pich M, Pallotti F, Formiggini G, Marchetti M, Parenti Castelli G, Bovina C. Oxidative stress, antioxidant defences and aging. Biofactors 1998; 8:195-204. [PMID: 9914819 DOI: 10.1002/biof.5520080305] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Apoptosis and aging share common mechanisms in oxidative stress and mitochondrial involvement. Treatment of cultured neuroblastoma cells with a radical initiator induced apoptosis; raise in hydrogen peroxide and release of cytochrome c from mitochondria preceded collapse of mitochondrial potential and cell death. In rat hepatocytes treated with adriamycin incubation with exogenous Coenzyme Q10 counteracted the drug-induced increase of hydrogen peroxide and the fall of the mitochondrial potential, thus demonstrating the quinone antioxidant effect. Complex I activity and its rotenone sensitivity decreased in brain cortex non-synaptic mitochondria from old rats; a 5 kb mitochondrial DNA deletion was found only in the old rats. A similar behavior was found in human platelets from old individuals. The postulated energy decline was confirmed by the inhibitor sensitivities of platelet aggregation and lactate production. The lack of the 5 kb deletion in platelets throws doubts on mitochondrial DNA lesions as the only causes of mitochondrial dysfunction in aging.
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Affiliation(s)
- G Lenaz
- Dipartimento di Biochimica G. Moruzzi, Università di Bologna, Italy.
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Genova ML, Bovina C, Marchetti M, Pallotti F, Tietz C, Biagini G, Pugnaloni A, Viticchi C, Gorini A, Villa RF, Lenaz G. Decrease of rotenone inhibition is a sensitive parameter of complex I damage in brain non-synaptic mitochondria of aged rats. FEBS Lett 1997; 410:467-9. [PMID: 9237684 DOI: 10.1016/s0014-5793(97)00638-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We investigated NADH oxidation in non-synaptic and synaptic mitochondria from brain cortex of 4- and 24-month-old rats. The NADH oxidase activity was significantly lower in non-synaptic mitochondria from aged rats; we also found a significant decrease of sensitivity of NADH oxidation to the specific Complex I inhibitor, rotenone. Since the rotenone-binding site encompasses Complex I subunits encoded by mtDNA, these results are in accordance with the mitochondrial theory of aging, whereby somatic mtDNA mutations are at the basis of cellular senescence. Accordingly, a 5 kb deletion was detected only in the cortex of the aged animals.
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Affiliation(s)
- M L Genova
- Department of Biochemistry, University of Bologna, Italy
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