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Da Costa RT, Riggs LM, Solesio ME. Inorganic polyphosphate and the regulation of mitochondrial physiology. Biochem Soc Trans 2023; 51:2153-2161. [PMID: 37955101 PMCID: PMC10842919 DOI: 10.1042/bst20230735] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 10/30/2023] [Accepted: 10/30/2023] [Indexed: 11/14/2023]
Abstract
Inorganic polyphosphate (polyP) is an ancient polymer that is well-conserved throughout evolution. It is formed by multiple subunits of orthophosphates linked together by phosphoanhydride bonds. The presence of these bonds, which are structurally similar to those found in ATP, and the high abundance of polyP in mammalian mitochondria, suggest that polyP could be involved in the regulation of the physiology of the organelle, especially in the energy metabolism. In fact, the scientific literature shows an unequivocal role for polyP not only in directly regulating oxidative a phosphorylation; but also in the regulation of reactive oxygen species metabolism, mitochondrial free calcium homeostasis, and the formation and opening of mitochondrial permeability transitions pore. All these processes are closely interconnected with the status of mitochondrial bioenergetics and therefore play a crucial role in maintaining mitochondrial and cell physiology. In this invited review, we discuss the main scientific literature regarding the regulatory role of polyP in mammalian mitochondrial physiology, placing a particular emphasis on its impact on energy metabolism. Although the effects of polyP on the physiology of the organelle are evident; numerous aspects, particularly within mammalian cells, remain unclear and require further investigation. These aspects encompass, for example, advancing the development of more precise analytical methods, unraveling the mechanism responsible for sensing polyP levels, and understanding the exact molecular mechanism that underlies the effects of polyP on mitochondrial physiology. By increasing our understanding of the biology of this ancient and understudied polymer, we could unravel new pharmacological targets in diseases where mitochondrial dysfunction, including energy metabolism dysregulation, has been broadly described.
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Affiliation(s)
- Renata T Da Costa
- Department of Biology; and Center for Computational and Integrative Biology (CCIB), Rutgers University, Camden, NJ, U.S.A
| | - Lindsey M Riggs
- Department of Biology; and Center for Computational and Integrative Biology (CCIB), Rutgers University, Camden, NJ, U.S.A
| | - Maria E Solesio
- Department of Biology; and Center for Computational and Integrative Biology (CCIB), Rutgers University, Camden, NJ, U.S.A
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2
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García-Velázquez L, Massieu L. The proteomic effects of ketone bodies: implications for proteostasis and brain proteinopathies. Front Mol Neurosci 2023; 16:1214092. [PMID: 37575967 PMCID: PMC10413579 DOI: 10.3389/fnmol.2023.1214092] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 07/07/2023] [Indexed: 08/15/2023] Open
Abstract
A growing body of evidence supports the beneficial effects of the ketone bodies (KBs), acetoacetate and β-hydroxybutyrate (BHB), on diverse physiological processes and diseases. Hence, KBs have been suggested as therapeutic tools for neurodegenerative diseases. KBs are an alternative fuel during fasting and starvation as they can be converted to Ac-CoA to produce ATP. A ketogenic diet (KD), enriched in fats and low in carbohydrates, induces KB production in the liver and favors their use in the brain. BHB is the most abundant KB in the circulation; in addition to its role as energy fuel, it exerts many actions that impact the set of proteins in the cell and tissue. BHB can covalently bind to proteins in lysine residues as a new post-translational modification (PTM) named β-hydroxybutyrylation (Kbhb). Kbhb has been identified in many proteins where Kbhb sites can be critical for binding to other proteins or cofactors. Kbhb is mostly found in proteins involved in chromatin structure, DNA repair, regulation of spliceosome, transcription, and oxidative phosphorylation. Histones are the most studied family of proteins with this PTM, and H3K9bhb is the best studied histone mark. Their target genes are mainly related to cell metabolism, chromatin remodeling and the control of circadian rhythms. The role of Kbhb on physiological processes is poorly known, but it might link KB metabolism to cell signaling and genome regulation. BHB also impacts the proteome by influencing proteostasis. This KB can modulate the Unfolded Protein Response (UPR) and autophagy, two processes involved in the maintenance of protein homeostasis through the clearance of accumulated unfolded and damaged proteins. BHB can support proteostasis and regulate the UPR to promote metabolism adaptation in the liver and prevent cell damage in the brain. Also, BHB stimulates autophagy aiding to the degradation of accumulated proteins. Protein aggregation is common to proteinopathies like Alzheimer's (AD) and Parkinson's (PD) diseases, where the KD and BHB treatment have shown favorable effects. In the present review, the current literature supporting the effects of KBs on proteome conformation and proteostasis is discussed, as well as its possible impact on AD and PD.
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Affiliation(s)
| | - Lourdes Massieu
- Department of Molecular Neuropathology, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México (UNAM), México City, Mexico
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3
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Huynh TV, Rethi L, Chung CC, Yeh YH, Kao YH, Chen YJ. Class I HDAC modulates angiotensin II-induced fibroblast migration and mitochondrial overactivity. Eur J Clin Invest 2022; 52:e13712. [PMID: 34783022 DOI: 10.1111/eci.13712] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 11/07/2021] [Accepted: 11/13/2021] [Indexed: 12/11/2022]
Abstract
BACKGROUND Inhibition of histone deacetylases (HDACs) attenuates cardiac fibrosis. In this study, we evaluated whether the inhibition of class I HDACs can attenuate angiotensin II (ANG II)-induced fibrogenesis and mitochondrial malfunction through its effects on reactive oxygen species (ROS) and calcium dysregulation in human cardiac fibroblasts (CFs). METHODS Seahorse XF24 extracellular flux analyser, fluorescence staining, Western blotting, HDAC activity assays and Transwell migration assay were used to study mitochondrial respiration, adenosine triphosphate (ATP) production, mitochondrial calcium uptake and ROS, HDAC expression and activity and fibroblast activity in CFs without (control) or with ANG II (100 nM) and/or MS-275 (HDAC class 1 inhibitor, 10 μM) for 24 h. RESULTS ANG II increased HDAC activity without changing protein expression in CFs. Compared with controls, ANG II-treated CFs had greater migration activity, higher ATP production, maximal respiration and spare capacity with higher mitochondrial Ca2+ uptake and ROS generation, which was attenuated by the administration of MS-275. ANG II activated CFs by increasing mitochondrial calcium content and ATP production, which may be caused by increased HDAC activity. Inhibition of HDAC1 attenuated the effects of ANG II by reducing mitochondrial ROS generation and calcium overload. CONCLUSIONS Modulating mitochondrial function by regulation of HDAC may be a novel strategy for controlling CF activity.
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Affiliation(s)
- Tin Van Huynh
- International Ph.D. Program in Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Department of Interventional Cardiology, Thong Nhat Hospital, Ho Chi Minh City, Vietnam
| | - Lekha Rethi
- School of Biomedical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei, Taiwan
| | - Cheng-Chih Chung
- Division of Cardiology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Yung-Hsin Yeh
- Division of Cardiology, Chang Gung Memorial Hospital, Taoyuan, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yu-Hsun Kao
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Department of Medical Education and Research, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Yi-Jen Chen
- Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
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4
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Macrì R, Musolino V, Gliozzi M, Carresi C, Maiuolo J, Nucera S, Scicchitano M, Bosco F, Scarano F, Ruga S, Zito MC, Guarnieri L, Bombardelli E, Mollace V. Ferula L. Plant Extracts and Dose-Dependent Activity of Natural Sesquiterpene Ferutinin: From Antioxidant Potential to Cytotoxic Effects. Molecules 2020; 25:molecules25235768. [PMID: 33297504 PMCID: PMC7731292 DOI: 10.3390/molecules25235768] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 12/04/2020] [Accepted: 12/06/2020] [Indexed: 02/07/2023] Open
Abstract
The employment studies of natural extracts in the prevention and treatment of several diseases highlighted the role of different species of genus Ferula L., belonging to the Apiaceae family, dicotyledonous plants present in many temperate zones of our planet. Ferula communis L. is the main source of sesquiterpene ferutinin, a bioactive compound studied both in vitro and in vivo, because of different effects, such as phytoestrogenic, antioxidant, anti-inflammatory, but also antiproliferative and cytotoxic activity, performed in a dose-dependent and cell-dependent way. The present review will focus on the molecular mechanisms involved in the different activities of Ferutinin, starting from its antioxidant potential at low doses until its ionophoric property and the subsequent mitochondrial dysfunction induced through administration of high doses, which represent the key point of its anticancer action. Furthermore, we will summarize the data acquired from some experimental studies on different cell types and on several diseases. The results obtained showed an important antioxidant and phytoestrogenic regulation with lack of typical side effects related to estrogenic therapy. The preferential cell death induction for tumor cell lines suggests that ferutinin may have anti-neoplastic properties, and may be used as an antiproliferative and cytotoxic agent in an estrogen dependent and independent manner. Nevertheless, more data are needed to clearly understand the effect of ferutinin in animals before using it as a phytoestrogen or anticancer drug.
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Affiliation(s)
- Roberta Macrì
- Institute of Research for Food Safety & Health IRC-FSH, University Magna Graecia, 88100 Catanzaro, Italy; (M.G.); (C.C.); (J.M.); (S.N.); (M.S.); (F.B.); (F.S.); (S.R.); (M.C.Z.); (L.G.); (V.M.)
- Correspondence: (R.M.); (V.M.); Tel./Fax: +39-0961-3694301 (R.M. & V.M.)
| | - Vincenzo Musolino
- Institute of Research for Food Safety & Health IRC-FSH, University Magna Graecia, 88100 Catanzaro, Italy; (M.G.); (C.C.); (J.M.); (S.N.); (M.S.); (F.B.); (F.S.); (S.R.); (M.C.Z.); (L.G.); (V.M.)
- Correspondence: (R.M.); (V.M.); Tel./Fax: +39-0961-3694301 (R.M. & V.M.)
| | - Micaela Gliozzi
- Institute of Research for Food Safety & Health IRC-FSH, University Magna Graecia, 88100 Catanzaro, Italy; (M.G.); (C.C.); (J.M.); (S.N.); (M.S.); (F.B.); (F.S.); (S.R.); (M.C.Z.); (L.G.); (V.M.)
| | - Cristina Carresi
- Institute of Research for Food Safety & Health IRC-FSH, University Magna Graecia, 88100 Catanzaro, Italy; (M.G.); (C.C.); (J.M.); (S.N.); (M.S.); (F.B.); (F.S.); (S.R.); (M.C.Z.); (L.G.); (V.M.)
| | - Jessica Maiuolo
- Institute of Research for Food Safety & Health IRC-FSH, University Magna Graecia, 88100 Catanzaro, Italy; (M.G.); (C.C.); (J.M.); (S.N.); (M.S.); (F.B.); (F.S.); (S.R.); (M.C.Z.); (L.G.); (V.M.)
| | - Saverio Nucera
- Institute of Research for Food Safety & Health IRC-FSH, University Magna Graecia, 88100 Catanzaro, Italy; (M.G.); (C.C.); (J.M.); (S.N.); (M.S.); (F.B.); (F.S.); (S.R.); (M.C.Z.); (L.G.); (V.M.)
| | - Miriam Scicchitano
- Institute of Research for Food Safety & Health IRC-FSH, University Magna Graecia, 88100 Catanzaro, Italy; (M.G.); (C.C.); (J.M.); (S.N.); (M.S.); (F.B.); (F.S.); (S.R.); (M.C.Z.); (L.G.); (V.M.)
| | - Francesca Bosco
- Institute of Research for Food Safety & Health IRC-FSH, University Magna Graecia, 88100 Catanzaro, Italy; (M.G.); (C.C.); (J.M.); (S.N.); (M.S.); (F.B.); (F.S.); (S.R.); (M.C.Z.); (L.G.); (V.M.)
| | - Federica Scarano
- Institute of Research for Food Safety & Health IRC-FSH, University Magna Graecia, 88100 Catanzaro, Italy; (M.G.); (C.C.); (J.M.); (S.N.); (M.S.); (F.B.); (F.S.); (S.R.); (M.C.Z.); (L.G.); (V.M.)
| | - Stefano Ruga
- Institute of Research for Food Safety & Health IRC-FSH, University Magna Graecia, 88100 Catanzaro, Italy; (M.G.); (C.C.); (J.M.); (S.N.); (M.S.); (F.B.); (F.S.); (S.R.); (M.C.Z.); (L.G.); (V.M.)
| | - Maria Caterina Zito
- Institute of Research for Food Safety & Health IRC-FSH, University Magna Graecia, 88100 Catanzaro, Italy; (M.G.); (C.C.); (J.M.); (S.N.); (M.S.); (F.B.); (F.S.); (S.R.); (M.C.Z.); (L.G.); (V.M.)
| | - Lorenza Guarnieri
- Institute of Research for Food Safety & Health IRC-FSH, University Magna Graecia, 88100 Catanzaro, Italy; (M.G.); (C.C.); (J.M.); (S.N.); (M.S.); (F.B.); (F.S.); (S.R.); (M.C.Z.); (L.G.); (V.M.)
| | - Ezio Bombardelli
- Nutramed S.c.a.r.l., Complesso Ninì Barbieri, Roccelletta di Borgia, 88021 Catanzaro, Italy;
| | - Vincenzo Mollace
- Institute of Research for Food Safety & Health IRC-FSH, University Magna Graecia, 88100 Catanzaro, Italy; (M.G.); (C.C.); (J.M.); (S.N.); (M.S.); (F.B.); (F.S.); (S.R.); (M.C.Z.); (L.G.); (V.M.)
- Nutramed S.c.a.r.l., Complesso Ninì Barbieri, Roccelletta di Borgia, 88021 Catanzaro, Italy;
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5
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Dąbek A, Wojtala M, Pirola L, Balcerczyk A. Modulation of Cellular Biochemistry, Epigenetics and Metabolomics by Ketone Bodies. Implications of the Ketogenic Diet in the Physiology of the Organism and Pathological States. Nutrients 2020; 12:nu12030788. [PMID: 32192146 PMCID: PMC7146425 DOI: 10.3390/nu12030788] [Citation(s) in RCA: 99] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 03/05/2020] [Accepted: 03/11/2020] [Indexed: 12/13/2022] Open
Abstract
Ketone bodies (KBs), comprising β-hydroxybutyrate, acetoacetate and acetone, are a set of fuel molecules serving as an alternative energy source to glucose. KBs are mainly produced by the liver from fatty acids during periods of fasting, and prolonged or intense physical activity. In diabetes, mainly type-1, ketoacidosis is the pathological response to glucose malabsorption. Endogenous production of ketone bodies is promoted by consumption of a ketogenic diet (KD), a diet virtually devoid of carbohydrates. Despite its recently widespread use, the systemic impact of KD is only partially understood, and ranges from physiologically beneficial outcomes in particular circumstances to potentially harmful effects. Here, we firstly review ketone body metabolism and molecular signaling, to then link the understanding of ketone bodies’ biochemistry to controversies regarding their putative or proven medical benefits. We overview the physiological consequences of ketone bodies’ consumption, focusing on (i) KB-induced histone post-translational modifications, particularly β-hydroxybutyrylation and acetylation, which appears to be the core epigenetic mechanisms of activity of β-hydroxybutyrate to modulate inflammation; (ii) inflammatory responses to a KD; (iii) proven benefits of the KD in the context of neuronal disease and cancer; and (iv) consequences of the KD’s application on cardiovascular health and on physical performance.
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Affiliation(s)
- Arkadiusz Dąbek
- Department of Molecular Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland; (A.D.); (M.W.)
| | - Martyna Wojtala
- Department of Molecular Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland; (A.D.); (M.W.)
| | - Luciano Pirola
- INSERM Unit 1060, CarMeN Laboratory, 165 Chemin du Grand Revoyet - BP12, F-69495 Pierre Bénite CEDEX, France;
| | - Aneta Balcerczyk
- Department of Molecular Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland; (A.D.); (M.W.)
- Correspondence: ; Tel.: +48 42 635 45 10
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6
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Solesio ME, Garcia Del Molino LC, Elustondo PA, Diao C, Chang JC, Pavlov EV. Inorganic polyphosphate is required for sustained free mitochondrial calcium elevation, following calcium uptake. Cell Calcium 2020; 86:102127. [PMID: 31954928 PMCID: PMC7024051 DOI: 10.1016/j.ceca.2019.102127] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 11/17/2019] [Accepted: 11/19/2019] [Indexed: 01/17/2023]
Abstract
Mitochondrial free calcium is critically linked to the regulation of cellular metabolism. Free ionic calcium concentration within these organelles is determined by the interplay between two processes: exchange across the mitochondrial inner membrane and calcium-buffering within the matrix. During stimulated calcium uptake, calcium is primarily buffered by orthophosphate, preventing calcium toxicity while allowing for well-regulated yet elevated calcium loads. However, if limited to orthophosphates only, this buffering system is expected to lead to the irreversible formation of insoluble precipitates, which are not observed in living cells, under physiological conditions. Here, we demonstrate that the regulation of free mitochondrial calcium requires the presence of free inorganic polyphosphate (polyP) within the organelle. We found that the overexpression of a mitochondrial-targeted enzyme hydrolyzing polyP leads to the loss of the cellular ability to maintain elevated calcium concentrations within the organelle, following stimulated cytoplasmic signal. We hypothesize that the presence of polyP prevents the formation of calcium-phosphate insoluble clusters, allowing for the maintenance of elevated free calcium levels, during stimulated calcium uptake.
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Affiliation(s)
- Maria E Solesio
- Department of Basic Sciences, New York University, New York, NY, USA
| | | | - Pia A Elustondo
- Department of Physiology and Biophysics, Dalhousie University, Halifax, NS, Canada
| | - Catherine Diao
- Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada
| | - Joshua C Chang
- Epidemiology and Biostatistics Section, Rehabilitation Medicine, Clinical Center, The National Institutes of Health, Bethesda, MD, USA; Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, The National Institutes of Health, Bethesda, MD, USA
| | - Evgeny V Pavlov
- Department of Basic Sciences, New York University, New York, NY, USA.
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7
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Bonartsev AP, Voinova VV, Bonartseva GA. Poly(3-hydroxybutyrate) and Human Microbiota (Review). APPL BIOCHEM MICRO+ 2018. [DOI: 10.1134/s0003683818060066] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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8
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Solesio ME, Peixoto PM, Debure L, Madamba SM, de Leon MJ, Wisniewski T, Pavlov EV, Fossati S. Carbonic anhydrase inhibition selectively prevents amyloid β neurovascular mitochondrial toxicity. Aging Cell 2018; 17:e12787. [PMID: 29873184 PMCID: PMC6052473 DOI: 10.1111/acel.12787] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/26/2018] [Indexed: 11/27/2022] Open
Abstract
Mounting evidence suggests that mitochondrial dysfunction plays a causal role in the etiology and progression of Alzheimer's disease (AD). We recently showed that the carbonic anhydrase inhibitor (CAI) methazolamide (MTZ) prevents amyloid β (Aβ)-mediated onset of apoptosis in the mouse brain. In this study, we used MTZ and, for the first time, the analog CAI acetazolamide (ATZ) in neuronal and cerebral vascular cells challenged with Aβ, to clarify their protective effects and mitochondrial molecular mechanism of action. The CAIs selectively inhibited mitochondrial dysfunction pathways induced by Aβ, without affecting metabolic function. ATZ was effective at concentrations 10 times lower than MTZ. Both MTZ and ATZ prevented mitochondrial membrane depolarization and H2 O2 generation, with no effects on intracellular pH or ATP production. Importantly, the drugs did not primarily affect calcium homeostasis. This work suggests a new role for carbonic anhydrases (CAs) in the Aβ-induced mitochondrial toxicity associated with AD and cerebral amyloid angiopathy (CAA), and paves the way to AD clinical trials for CAIs, FDA-approved drugs with a well-known profile of brain delivery.
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Affiliation(s)
- María E. Solesio
- Department of Basic SciencesNew York University College of DentistryNew YorkNew York
| | - Pablo M. Peixoto
- Department of Natural SciencesBaruch CollegeGraduate CenterThe City University of New YorkNew YorkNew York
| | - Ludovic Debure
- Department of PsychiatryNew York University School of MedicineNew YorkNew York
| | - Stephen M. Madamba
- Department of Natural SciencesBaruch CollegeGraduate CenterThe City University of New YorkNew YorkNew York
| | - Mony J. de Leon
- Department of PsychiatryNew York University School of MedicineNew YorkNew York
| | - Thomas Wisniewski
- Department of NeurologyCenter for Cognitive NeurologyNew York University School of MedicineNew YorkNew York
| | - Evgeny V. Pavlov
- Department of Basic SciencesNew York University College of DentistryNew YorkNew York
| | - Silvia Fossati
- Department of PsychiatryNew York University School of MedicineNew YorkNew York
- Department of NeurologyCenter for Cognitive NeurologyNew York University School of MedicineNew YorkNew York
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9
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Angelova PR, Vinogradova D, Neganova ME, Serkova TP, Sokolov VV, Bachurin SO, Shevtsova EF, Abramov AY. Pharmacological Sequestration of Mitochondrial Calcium Uptake Protects Neurons Against Glutamate Excitotoxicity. Mol Neurobiol 2018; 56:2244-2255. [PMID: 30008072 PMCID: PMC6394642 DOI: 10.1007/s12035-018-1204-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 06/26/2018] [Indexed: 12/14/2022]
Abstract
Neuronal excitotoxicity which is induced by exposure to excessive extracellular glutamate is shown to be involved in neuronal cell death in acute brain injury and a number of neurological diseases. High concentration of glutamate induces calcium deregulation which results in mitochondrial calcium overload and mitochondrial depolarization that triggers the mechanism of cell death. Inhibition of mitochondrial calcium uptake could be potentially neuroprotective but complete inhibition of mitochondrial calcium uniporter could result in the loss of some physiological processes linked to Ca2+ in mitochondria. Here, we found that a novel compound, TG-2112x, can inhibit only the lower concentrations mitochondrial calcium uptake (induced by 100 nM-5 μM) but not the uptake induced by higher concentrations of calcium (10 μM and higher). This effect was not associated with changes in mitochondrial membrane potential and cellular respiration. However, a pre-treatment of neurons with TG-2112x protected the neurons against calcium overload upon application of toxic concentrations of glutamate. Thus, sequestration of mitochondrial calcium uptake protected the neurons against glutamate-induced mitochondrial depolarization and cell death. In our hands, TG-2112x was also protective against ionomycin-induced cell death. Hence, low rate mitochondrial calcium uptake plays an underestimated role in mitochondrial function, and its inhibition could protect neurons against calcium overload and cell death in glutamate excitotoxicity.
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Affiliation(s)
- Plamena R Angelova
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Darya Vinogradova
- Institute of Physiologically Active Compounds Russian Academy of Sciences, Chernogolovka, 142432, Russia
| | - Margarita E Neganova
- Institute of Physiologically Active Compounds Russian Academy of Sciences, Chernogolovka, 142432, Russia
| | - Tatiana P Serkova
- Institute of Physiologically Active Compounds Russian Academy of Sciences, Chernogolovka, 142432, Russia
| | - Vladimir V Sokolov
- Institute of Physiologically Active Compounds Russian Academy of Sciences, Chernogolovka, 142432, Russia
| | - Sergey O Bachurin
- Institute of Physiologically Active Compounds Russian Academy of Sciences, Chernogolovka, 142432, Russia
| | - Elena F Shevtsova
- Institute of Physiologically Active Compounds Russian Academy of Sciences, Chernogolovka, 142432, Russia.
| | - Andrey Y Abramov
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK.
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10
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Plant growth-promoting bacterium Pseudomonas fluorescens FR1 secrets a novel type of extracellular polyhydroxybutyrate polymerase involved in abiotic stress response in plants. Biotechnol Lett 2018; 40:1419-1423. [DOI: 10.1007/s10529-018-2576-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 05/22/2018] [Indexed: 10/16/2022]
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11
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Wüst RCI, Helmes M, Martin JL, van der Wardt TJT, Musters RJP, van der Velden J, Stienen GJM. Rapid frequency-dependent changes in free mitochondrial calcium concentration in rat cardiac myocytes. J Physiol 2017; 595:2001-2019. [PMID: 28028811 DOI: 10.1113/jp273589] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 12/16/2016] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Calcium ions regulate mitochondrial ATP production and contractile activity and thus play a pivotal role in matching energy supply and demand in cardiac muscle. The magnitude and kinetics of the changes in free mitochondrial calcium concentration in cardiac myocytes are largely unknown. Rapid stimulation frequency-dependent increases but relatively slow decreases in free mitochondrial calcium concentration were observed in rat cardiac myocytes. This asymmetry caused a rise in the mitochondrial calcium concentration with stimulation frequency. These results provide insight into the mechanisms of mitochondrial calcium uptake and release that are important in healthy and diseased myocardium. ABSTRACT Calcium ions regulate mitochondrial ATP production and contractile activity and thus play a pivotal role in matching energy supply and demand in cardiac muscle. Little is known about the magnitude and kinetics of the changes in free mitochondrial calcium concentration in cardiomyocytes. Using adenoviral infection, a ratiometric mitochondrially targeted Förster resonance energy transfer (FRET)-based calcium indicator (4mtD3cpv, MitoCam) was expressed in cultured adult rat cardiomyocytes and the free mitochondrial calcium concentration ([Ca2+ ]m ) was measured at different stimulation frequencies (0.1-4 Hz) and external calcium concentrations (1.8-3.6 mm) at 37°C. Cytosolic calcium concentrations were assessed under the same experimental conditions in separate experiments using Fura-4AM. The increases in [Ca2+ ]m during electrical stimulation at 0.1 Hz were rapid (rise time = 49 ± 2 ms), while the decreases in [Ca2+ ]m occurred more slowly (decay half time = 1.17 ± 0.07 s). Model calculations confirmed that this asymmetry caused the rise in [Ca2+ ]m during diastole observed at elevated stimulation frequencies. Inhibition of the mitochondrial sodium-calcium exchanger (mNCE) resulted in a rise in [Ca2+ ]m at baseline and, paradoxically, in an acceleration of Ca2+ release. IN CONCLUSION rapid increases in [Ca2+ ]m allow for fast adjustment of mitochondrial ATP production to increases in myocardial demand on a beat-to-beat basis and mitochondrial calcium release depends on mNCE activity and mitochondrial calcium buffering.
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Affiliation(s)
- Rob C I Wüst
- Department of Physiology, Institute for Cardiovascular Research, VU University Medical Centre, Amsterdam, the Netherlands
| | - Michiel Helmes
- Department of Physiology, Institute for Cardiovascular Research, VU University Medical Centre, Amsterdam, the Netherlands.,IonOptix LLC, Milton, MA, USA
| | - Jody L Martin
- Cell and Molecular Physiology, Loyola University, Chicago, IL, USA
| | - Thomas J T van der Wardt
- Department of Physiology, Institute for Cardiovascular Research, VU University Medical Centre, Amsterdam, the Netherlands
| | - René J P Musters
- Department of Physiology, Institute for Cardiovascular Research, VU University Medical Centre, Amsterdam, the Netherlands
| | - Jolanda van der Velden
- Department of Physiology, Institute for Cardiovascular Research, VU University Medical Centre, Amsterdam, the Netherlands
| | - Ger J M Stienen
- Department of Physiology, Institute for Cardiovascular Research, VU University Medical Centre, Amsterdam, the Netherlands.,Faculty of Science, Department of Physics and Astronomy, VU University, Amsterdam, the Netherlands
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12
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Mitochondrial Calcium Uptake in Activation of the Permeability Transition Pore and Cell Death. MOLECULAR BASIS FOR MITOCHONDRIAL SIGNALING 2017. [DOI: 10.1007/978-3-319-55539-3_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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13
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Inorganic polyphosphate (polyP) as an activator and structural component of the mitochondrial permeability transition pore. Biochem Soc Trans 2016; 44:7-12. [PMID: 26862181 DOI: 10.1042/bst20150206] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Mitochondrial permeability transition pore (mPTP) is a large channel located in the mitochondrial inner membrane. The opening of mPTP during pathological calcium overload leads to the membrane depolarization and disruption of ATP production. mPTP activation has been implicated as a central event during the process of stress-induced cell death. mPTP is a supramolecular complex composed of many proteins. Recent studies suggest that mitochondrial ATPase plays the central role in the formation of mPTP. However, the structure of the central conducting pore part of mPTP (mPTPore) remains elusive. Here we review current models proposed for the mPTPore and involvement of polyP in its formation and regulation. We discuss the underestimated role of polyP as an effector and a putative structural component of the mPTPore. We propose the hypothesis that inclusion of polyP can explain such properties of mPTP activity as calcium activation, selectivity and voltage-dependence.
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14
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Elustondo PA, Nichols M, Robertson GS, Pavlov EV. Mitochondrial Ca2+ uptake pathways. J Bioenerg Biomembr 2016; 49:113-119. [DOI: 10.1007/s10863-016-9676-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 09/05/2016] [Indexed: 12/19/2022]
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15
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Solesio ME, Demirkhanyan L, Zakharian E, Pavlov EV. Contribution of inorganic polyphosphate towards regulation of mitochondrial free calcium. Biochim Biophys Acta Gen Subj 2016; 1860:1317-25. [PMID: 26994920 DOI: 10.1016/j.bbagen.2016.03.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 03/08/2016] [Accepted: 03/15/2016] [Indexed: 12/31/2022]
Abstract
BACKGROUND Calcium signaling plays a key role in the regulation of multiple processes in mammalian mitochondria, from cellular bioenergetics to the induction of stress-induced cell death. While the total concentration of calcium inside the mitochondria can increase by several orders of magnitude, the concentration of bioavailable free calcium in mitochondria is maintained within the micromolar range by the mitochondrial calcium buffering system. This calcium buffering system involves the participation of inorganic phosphate. However, the mechanisms of its function are not yet understood. Specifically, it is not clear how calcium-orthophosphate interactions, which normally lead to formation of insoluble precipitates, are capable to dynamically regulate free calcium concentration. Here we test the hypothesis that inorganic polyphosphate, which is a polymerized form of orthophosphate, is capable to from soluble complexes with calcium, playing a significant role in the regulation of the mitochondrial free calcium concentration. METHODS We used confocal fluorescence microscopy to measure the relative levels of mitochondrial free calcium in cultured hepatoma cells (HepG2) with variable levels of inorganic polyphosphate (polyP). RESULTS The depletion of polyP leads to the significantly lower levels of mitochondrial free calcium concentration under conditions of pathological calcium overload. These results are coherent with previous observations showing that inorganic polyphosphate (polyP) can inhibit calcium-phosphate precipitation and, thus, increase the amount of free calcium. CONCLUSIONS Inorganic polyphosphate plays an important role in the regulation of mitochondrial free calcium, leading to its significant increase. GENERAL SIGNIFICANCE Inorganic polyphosphate is a previously unrecognized integral component of the mitochondrial calcium buffering system.
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Affiliation(s)
- M E Solesio
- Department of Basic Sciences, New York University College of Dentistry, 345 East 24th Street, 10010 New York, NY, USA
| | - L Demirkhanyan
- Department of Cancer Biology and Pharmacology, 1 Illini Drive, 61605 Peoria, IL, USA
| | - E Zakharian
- Department of Cancer Biology and Pharmacology, 1 Illini Drive, 61605 Peoria, IL, USA
| | - E V Pavlov
- Department of Basic Sciences, New York University College of Dentistry, 345 East 24th Street, 10010 New York, NY, USA.
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16
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Baev AY, Negoda A, Abramov AY. Modulation of mitochondrial ion transport by inorganic polyphosphate - essential role in mitochondrial permeability transition pore. J Bioenerg Biomembr 2016; 49:49-55. [PMID: 26888154 PMCID: PMC5331082 DOI: 10.1007/s10863-016-9650-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 01/27/2016] [Indexed: 12/30/2022]
Abstract
Inorganic polyphosphate (polyP) is a biopolymer of phosphoanhydride-linked orthophosphate residues. PolyP is involved in multiple cellular processes including mitochondrial metabolism and cell death. We used artificial membranes and isolated mitochondria to investigate the role of the polyP in mitochondrial ion transport and in activation of PTP. Here, we found that polyP can modify ion permeability of de-energised mitochondrial membranes but not artificial membranes. This permeability was selective for Ba2+ and Ca2+ but not for other monovalent and bivalent cations and can be blocked by inhibitors of the permeability transition pore – cyclosporine A or ADP. Lower concentrations of polyP modulate calcium dependent permeability transition pore opening. Increase in polyP concentrations and elongation chain length of the polymer causes calcium independent swelling in energized conditions. Physiologically relevant concentrations of inorganic polyP can regulate calcium dependent as well calcium independent mitochondrial permeability transition pore opening. This raises the possibility that cytoplasmic polyP can be an important contributor towards regulation of the cell death.
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Affiliation(s)
- Artyom Y Baev
- National University of Uzbekistan, Tashkent, Uzbekistan.,Department of Physiology and Biophysics, Dalhousie University, Halifax, Canada
| | - Alexander Negoda
- Department of Physiology and Biophysics, Dalhousie University, Halifax, Canada
| | - Andrey Y Abramov
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK.
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17
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Role of inorganic polyphosphate in mammalian cells: from signal transduction and mitochondrial metabolism to cell death. Biochem Soc Trans 2016; 44:40-5. [DOI: 10.1042/bst20150223] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Inorganic polyphosphate (polyP) is a polymer compromised of linearly arranged orthophosphate units that are linked through high-energy phosphoanhydride bonds. The chain length of this polymer varies from five to several thousand orthophosphates. PolyP is distributed in the most of the living organisms and plays multiple functions in mammalian cells, it is important for blood coagulation, cancer, calcium precipitation, immune response and many others. Essential role of polyP is shown for mitochondria, from implication into energy metabolism and mitochondrial calcium handling to activation of permeability transition pore (PTP) and cell death. PolyP is a gliotransmitter which transmits the signal in astrocytes via activation of P2Y1 receptors and stimulation of phospholipase C. PolyP-induced calcium signal in astrocytes can be stimulated by different lengths of this polymer but only long chain polyP induces mitochondrial depolarization by inhibition of respiration and opening of the PTP. It leads to induction of astrocytic cell death which can be prevented by inhibition of PTP with cyclosporine A. Thus, medium- and short-length polyP plays role in signal transduction and mitochondrial metabolism of astrocytes and long chain of this polymer can be toxic for the cells.
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18
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Dubis A, Zamaraeva MV, Siergiejczyk L, Charishnikova O, Shlyonsky V. Ferutinin as a Ca(2+) complexone: lipid bilayers, conductometry, FT-IR, NMR studies and DFT-B3LYP calculations. Dalton Trans 2015; 44:16506-15. [PMID: 26331156 DOI: 10.1039/c4dt03892d] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Calcium ionophoretic properties of ferutinin were re-evaluated in solvent-containing bilayer lipid membranes. The slopes of conductance-concentration curves suggest that in the presence of a solvent in the membrane the majority of complexes appear to consist of a single terpenoid molecule bound to one Ca ion. By contrast, the stoichiometry of ferutinin-Ca(2+) complexes in acetone determined using the conductometric method was 2 : 1. While the cation-cation selectivity of ferutinin did not change, the cation-anion selectivity slightly decreased in solvent containing membranes. FT-IR and NMR data together with DFT calculations at the B3LYP/6-31G(d) level of theory indicate that in the absence of Ca ions ferutinin molecules are hydrogen-bonded at the phenol hydroxyl groups. The variations of absorption assigned to -OH and -C-O stretching mode suggest that ferutinin interacts strongly with Ca ions via the hydroxyl group of ferutinol and carboxyl oxygen of the complex ether bond. The coordination through the carbonyl group of ferutinin was demonstrated by theoretical calculations. Taken together, ferutinin molecules form H-bonded dimers, while complexation of Ca(2+) by ferutinin ruptures this hydrogen bond due to spatial re-orientation of the ferutinin molecules from parallel to antiparallel alignment.
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Affiliation(s)
- A Dubis
- Institute of Chemistry, University of Bialystok, Poland
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19
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Dedkova EN, Blatter LA. Role of β-hydroxybutyrate, its polymer poly-β-hydroxybutyrate and inorganic polyphosphate in mammalian health and disease. Front Physiol 2014; 5:260. [PMID: 25101001 PMCID: PMC4102118 DOI: 10.3389/fphys.2014.00260] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 06/19/2014] [Indexed: 12/14/2022] Open
Abstract
We provide a comprehensive review of the role of β-hydroxybutyrate (β-OHB), its linear polymer poly-β-hydroxybutyrate (PHB), and inorganic polyphosphate (polyP) in mammalian health and disease. β-OHB is a metabolic intermediate that constitutes 70% of ketone bodies produced during ketosis. Although ketosis has been generally considered as an unfavorable pathological state (e.g., diabetic ketoacidosis in type-1 diabetes mellitus), it has been suggested that induction of mild hyperketonemia may have certain therapeutic benefits. β-OHB is synthesized in the liver from acetyl-CoA by β-OHB dehydrogenase and can be used as alternative energy source. Elevated levels of PHB are associated with pathological states. In humans, short-chain, complexed PHB (cPHB) is found in a wide variety of tissues and in atherosclerotic plaques. Plasma cPHB concentrations correlate strongly with atherogenic lipid profiles, and PHB tissue levels are elevated in type-1 diabetic animals. However, little is known about mechanisms of PHB action especially in the heart. In contrast to β-OHB, PHB is a water-insoluble, amphiphilic polymer that has high intrinsic viscosity and salt-solvating properties. cPHB can form non-specific ion channels in planar lipid bilayers and liposomes. PHB can form complexes with polyP and Ca(2+) which increases membrane permeability. The biological roles played by polyP, a ubiquitous phosphate polymer with ATP-like bonds, have been most extensively studied in prokaryotes, however polyP has recently been linked to a variety of functions in mammalian cells, including blood coagulation, regulation of enzyme activity in cancer cells, cell proliferation, apoptosis and mitochondrial ion transport and energy metabolism. Recent evidence suggests that polyP is a potent activator of the mitochondrial permeability transition pore in cardiomyocytes and may represent a hitherto unrecognized key structural and functional component of the mitochondrial membrane system.
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Affiliation(s)
- Elena N Dedkova
- Department of Molecular Biophysics and Physiology, Rush University Medical Center Chicago, IL, USA
| | - Lothar A Blatter
- Department of Molecular Biophysics and Physiology, Rush University Medical Center Chicago, IL, USA
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20
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Elustondo PA, Angelova PR, Kawalec M, Michalak M, Kurcok P, Abramov AY, Pavlov EV. Polyhydroxybutyrate targets mammalian mitochondria and increases permeability of plasmalemmal and mitochondrial membranes. PLoS One 2013; 8:e75812. [PMID: 24086638 PMCID: PMC3781052 DOI: 10.1371/journal.pone.0075812] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 08/21/2013] [Indexed: 01/21/2023] Open
Abstract
Poly(3-hydroxybutyrate) (PHB) is a polyester of 3-hydroxybutyric acid (HB) that is ubiquitously present in all organisms. In higher eukaryotes PHB is found in the length of 10 to 100 HB units and can be present in free form as well as in association with proteins and inorganic polyphosphate. It has been proposed that PHB can mediate ion transport across lipid bilayer membranes. We investigated the ability of PHB to interact with living cells and isolated mitochondria and the effects of these interactions on membrane ion transport. We performed experiments using a fluorescein derivative of PHB (fluo-PHB). We found that fluo-PHB preferentially accumulated inside the mitochondria of HeLa cells. Accumulation of fluo-PHB induced mitochondrial membrane depolarization. This membrane depolarization was significantly delayed by the inhibitor of the mitochondrial permeability transition pore - Cyclosporin A. Further experiments using intact cells as well as isolated mitochondria confirmed that the effects of PHB directly linked to its ability to facilitate ion transport, including calcium, across the membranes. We conclude that PHB demonstrates ionophoretic properties in biological membranes and this effect is most profound in mitochondria due to the selective accumulation of the polymer in this organelle.
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Affiliation(s)
- Pia A. Elustondo
- Department of Physiology and Biophysics, Dalhousie University, Halifax, Novia Scotia, Canada
| | | | - Michał Kawalec
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, Zabrze, Poland
| | - Michał Michalak
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, Zabrze, Poland
| | - Piotr Kurcok
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, Zabrze, Poland
| | | | - Evgeny V. Pavlov
- Department of Physiology and Biophysics, Dalhousie University, Halifax, Novia Scotia, Canada
- * E-mail:
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21
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Kane DA, Pavlov EV. Calculation of ion currents across the inner membrane of functionally intact mitochondria. Channels (Austin) 2013; 7:426-31. [PMID: 24037064 DOI: 10.4161/chan.26290] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Mitochondrial ion transport systems play a central role in cell physiology. Rates of Ca (2+) and K(+) transport across the inner mitochondrial membrane have been derived from the measurement of ion accumulation over time within functional isolated mitochondria or mitochondria of cultured cells. Alternatively, the electrical currents generated by ionic flux have been directly measured in purified and swollen mitochondrial samples (mitoplasts) or reconstituted channels, and typically range from 1 pA to several 100s pA. However, the direct electrophysiological approach necessarily requires extensive processing of the mitochondria prior to measurement, which can only be performed on isolated mitoplasts. To compare rates of mitochondrial ion transport measured in electrophysiological experiments to those measured in intact mitochondria and cells, we converted published rates of mitochondrial ion uptake into units of ionic current. We estimate that for monovalent ions, uptake by intact mitochondria at the rate of 1 nmol ∙ mg(-1) protein ∙ min(-1) is equivalent to 0.2 fA of current per whole single mitochondrion (0.4 fA for divalent ions). In intact mitochondria, estimated rates of electrogenic cation uptake are limited to 1-100 fA of integral current per single mitochondrion. These estimates are orders of magnitude lower than the currents through mitochondrial channels directly measured via patch-clamp or artificial lipid bilayer approaches.
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Affiliation(s)
- Daniel A Kane
- Department of Human Kinetics; St. Francis Xavier University; Antigonish, Nova Scotia, Canada
| | - Evgeny V Pavlov
- Department of Physiology and Biophysics; Dalhousie University; Halifax, Nova Scotia, Canada
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