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Al-Suhaimi E, AlQuwaie R, AlSaqabi R, Winarni D, Dewi FRP, AlRubaish AA, Shehzad A, Elaissari A. Hormonal orchestra: mastering mitochondria's role in health and disease. Endocrine 2024:10.1007/s12020-024-03967-1. [PMID: 39172335 DOI: 10.1007/s12020-024-03967-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Accepted: 07/10/2024] [Indexed: 08/23/2024]
Abstract
Mitochondria is a subcellular organelle involved in the pathogenesis of cellular stress, immune responses, differentiation, metabolic disorders, aging, and death by regulating process of fission, fusion, mitophagy, and transport. However, an increased interest in mitochondria as powerhouse for ATP production, the mechanisms of mitochondria-mediated cellular dysfunction in response to hormonal interaction remains unknown. Mitochondrial matrix contains chaperones and proteases that regulate intrinsic apoptosis pathway through pro-apoptotic Bcl-2 family's proteins Bax/Bak, and Cyt C release, and induces caspase-dependent and independent cells death. Energy and growth regulators such as thyroid hormones have profound effect on mitochondrial inner membrane protein and lipid compositions, ATP production by regulating oxidative phosphorylation system. Mitochondria contain cholesterol side-chain cleavage enzyme, P450scc, ferredoxin, and ferredoxin reductase providing an essential site for steroid hormones biosynthesis. In line with this, neurohormones such as oxytocin, vasopressin, and melatonin are correlated with mitochondrial integrity, displaying therapeutic implications for inflammatory and immune responses. Melatonin's also displayed protective role against oxidative stress and mitochondrial synthesis of ROS, suggesting a defense mechanism against aging-related diseases. An imbalance in mitochondrial bioenergetics can cause neurodegenerative disorders, cardiovascular diseases, and cancers. Hormone-induced PGC-1α stimulates mitochondrial biogenesis via activation of NRF1 and NRF2, which in turn triggers mtTFA in brown adipose and cardiac myocytes. Mitochondria can be transferred through cells merging, exosome-mediated transfer, and tunneling through nanotubes. By delineating the underlying molecular mechanism of hormonal mitochondrial interaction, this study reviews the dynamics mechanisms of mitochondria and its effects on cellular level, health, diseases, and therapeutic strategies targeting mitochondrial diseases.
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Affiliation(s)
- Ebtesam Al-Suhaimi
- Vice presidency for Scientific Research and Innovation, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia.
- King Abdulaziz and his Companions Foundation for Giftedness and Creativity "Mawhiba", Riyadh, Saudi Arabia.
| | - Rahaf AlQuwaie
- Master Program of Biotechnology, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Reem AlSaqabi
- Master Program of Biotechnology, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Dwi Winarni
- Department of Biology, Faculty of Science and Technology, Universitas Airlangga, Surabaya, East Java, Indonesia
| | - Firli Rahmah Primula Dewi
- Department of Biology, Faculty of Science and Technology, Universitas Airlangga, Surabaya, East Java, Indonesia
| | - Abdullah A AlRubaish
- College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Adeeb Shehzad
- Biodiversity Unit, Research Center, Dhofar University, Salalah, Oman
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Zoratti M, Biasutto L, Parrasia S, Szabo I. Mitochondrial permeability transition pore: a snapshot of a therapeutic target. Expert Opin Ther Targets 2024; 28:1-3. [PMID: 38235549 DOI: 10.1080/14728222.2024.2306337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 01/12/2024] [Indexed: 01/19/2024]
Affiliation(s)
- Mario Zoratti
- CNR Neuroscience Institute, Padova Unit, Padova, Italy
- Department Biomedical Sciences, University of Padova, Padova, Italy
| | - Lucia Biasutto
- CNR Neuroscience Institute, Padova Unit, Padova, Italy
- Department Biomedical Sciences, University of Padova, Padova, Italy
| | | | - Ildikó Szabo
- Department Biology, University of Padova, Padova, Italy
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3
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Szabo I, Szewczyk A. Mitochondrial Ion Channels. Annu Rev Biophys 2023; 52:229-254. [PMID: 37159294 DOI: 10.1146/annurev-biophys-092622-094853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Mitochondria are involved in multiple cellular tasks, such as ATP synthesis, metabolism, metabolite and ion transport, regulation of apoptosis, inflammation, signaling, and inheritance of mitochondrial DNA. The majority of the correct functioning of mitochondria is based on the large electrochemical proton gradient, whose component, the inner mitochondrial membrane potential, is strictly controlled by ion transport through mitochondrial membranes. Consequently, mitochondrial function is critically dependent on ion homeostasis, the disturbance of which leads to abnormal cell functions. Therefore, the discovery of mitochondrial ion channels influencing ion permeability through the membrane has defined a new dimension of the function of ion channels in different cell types, mainly linked to the important tasks that mitochondrial ion channels perform in cell life and death. This review summarizes studies on animal mitochondrial ion channels with special focus on their biophysical properties, molecular identity, and regulation. Additionally, the potential of mitochondrial ion channels as therapeutic targets for several diseases is briefly discussed.
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Affiliation(s)
- Ildiko Szabo
- Department of Biology, University of Padova, Italy;
| | - Adam Szewczyk
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland;
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Varanita T, Angi B, Scattolini V, Szabo I. Kv1.3 K + Channel Physiology Assessed by Genetic and Pharmacological Modulation. Physiology (Bethesda) 2023; 38:0. [PMID: 35998249 DOI: 10.1152/physiol.00010.2022] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Potassium channels are widespread over all kingdoms and play an important role in the maintenance of cellular ionic homeostasis. Kv1.3 is a voltage-gated potassium channel of the Shaker family with a wide tissue expression and a well-defined pharmacology. In recent decades, experiments mainly based on pharmacological modulation of Kv1.3 have highlighted its crucial contribution to different fundamental processes such as regulation of proliferation, apoptosis, and metabolism. These findings link channel function to various pathologies ranging from autoimmune diseases to obesity and cancer. In the present review, we briefly summarize studies employing Kv1.3 knockout animal models to confirm such roles and discuss the findings in comparison to the results obtained by pharmacological modulation of Kv1.3 in various pathophysiological settings. We also underline how these studies contributed to our understanding of channel function in vivo and propose possible future directions.
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Affiliation(s)
| | - Beatrice Angi
- Department of Biology, University of Padova, Padova, Italy
| | | | - Ildiko Szabo
- Department of Biology, University of Padova, Padova, Italy
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Bian H, Ma D, Pan F, Zhang X, Xin K, Zhang X, Yang Y, Peng X, Xiao Y. Cardiolipin-Targeted NIR-II Fluorophore Causes "Avalanche Effects" for Re-Engaging Cancer Apoptosis and Inhibiting Metastasis. J Am Chem Soc 2022; 144:22562-22573. [PMID: 36445324 DOI: 10.1021/jacs.2c08602] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Restoring innate apoptosis and simultaneously inhibiting metastasis by a molecular drug is an effective cancer therapeutic approach. Herein, a large rigid and V-shaped NIR-II dye, DUT850, is rationally designed for potential cardiolipin (CL)-targeted chemo-phototheranostic application. DUT850 displays moderate NIR-II fluorescence, excellent photodynamic therapy (PDT) and photothermal therapy (PTT) performance, and ultra-high photostability. More importantly, the unique rigid V-shaped backbone, positive charge, and lipophilicity of DUT850 afford its specific recognition and efficient binding to CL; such an interaction of DUT850-CL induced a spectrum of physiological disruptions, including translocation of cytochrome c, Ca2+ overload, reactive oxygen species burst, and ATP depletion, which not only activated cancer cell apoptosis but also inhibited tumor metastasis both in vitro and in vivo. Furthermore, the tight binding of DUT850-CL improves the phototoxicity of DUT850 toward cancer cells (IC50 as low as 90 nM) under safe 808 nm laser irradiation (330 mW cm-2). Upon encapsulation into bovine serum albumin (BSA), DUT850@BSA exerted a synergetic chemo-PDT-PTT effect on the 4T1 tumor mouse model, eventually leading to solid tumor annihilation and metastasis inhibition, which could be followed in real time with the NIR-II fluorescence of DUT850. This work contributed a promising approach for simultaneously re-engaging cancer cell apoptotic networks and activating the anti-metastasis pathway by targeting a pivotal upstream effector, which will bring a medical boon for inhibition of tumor proliferation and metastasis.
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Affiliation(s)
- Hui Bian
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials Oriented Chemical Engineering, Dalian University of Technology, 2 Linggong Road, Dalian 116024, P. R. China
| | - Dandan Ma
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials Oriented Chemical Engineering, Dalian University of Technology, 2 Linggong Road, Dalian 116024, P. R. China
| | - Fei Pan
- Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, P. R. China
| | - Xiaodong Zhang
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
| | - Kai Xin
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
| | - Xinfu Zhang
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials Oriented Chemical Engineering, Dalian University of Technology, 2 Linggong Road, Dalian 116024, P. R. China
| | - Youjun Yang
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
| | - Xiaojun Peng
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials Oriented Chemical Engineering, Dalian University of Technology, 2 Linggong Road, Dalian 116024, P. R. China
| | - Yi Xiao
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials Oriented Chemical Engineering, Dalian University of Technology, 2 Linggong Road, Dalian 116024, P. R. China
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Multiple Mechanisms Converging on Transcription Factor EB Activation by the Natural Phenol Pterostilbene. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2021:7658501. [PMID: 34992716 PMCID: PMC8727145 DOI: 10.1155/2021/7658501] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 10/22/2021] [Accepted: 11/17/2021] [Indexed: 11/17/2022]
Abstract
Pterostilbene (Pt) is a potentially beneficial plant phenol. In contrast to many other natural compounds (including the more celebrated resveratrol), Pt concentrations producing significant effects in vitro can also be reached with relative ease in vivo. Here we focus on some of the mechanisms underlying its activity, those involved in the activation of transcription factor EB (TFEB). A set of processes leading to this outcome starts with the generation of ROS, attributed to the interaction of Pt with complex I of the mitochondrial respiratory chain, and spreads to involve Ca2+ mobilization from the ER/mitochondria pool, activation of CREB and AMPK, and inhibition of mTORC1. TFEB migration to the nucleus results in the upregulation of autophagy and lysosomal and mitochondrial biogenesis. Cells exposed to several μM levels of Pt experience a mitochondrial crisis, an indication for using low doses in therapeutic or nutraceutical applications. Pt afforded significant functional improvements in a zebrafish embryo model of ColVI-related myopathy, a pathology which also involves defective autophagy. Furthermore, long-term supplementation with Pt reduced body weight gain and increased transcription levels of Ppargc1a and Tfeb in a mouse model of diet-induced obesity. These in vivo findings strengthen the in vitro observations and highlight the therapeutic potential of this natural compound.
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Li Y, Wu J, Yang M, Wei L, Wu H, Wang Q, Shi H. Physiological evidence of mitochondrial permeability transition pore opening caused by lipid deposition leading to hepatic steatosis in db/db mice. Free Radic Biol Med 2021; 162:523-532. [PMID: 33220425 DOI: 10.1016/j.freeradbiomed.2020.11.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 11/02/2020] [Accepted: 11/11/2020] [Indexed: 02/07/2023]
Abstract
Mitochondrial permeability transition pore (mPTP) is an important regulator in cell apoptosis and necrosis. However, its role in hepatic steatosis, especially its electrophysiological properties transformation remains elusive. Herein, using diabetes mice, we investigated the role of mPTP in hepatic steatosis triggered by diabetes and the mechanisms involved. We found that hepatic steatosis altered mitochondrial morphology, generating mega mitochondria, mitochondria swelling, calcein fluorescence quenching and mitochondrial membrane potential depolarization. At the same time, we confirmed an augmented mPTP opening with patch clamping in liver mitoplasts in db/db mice and a similar transformation with arachidonic acid (AA) simulating liquid deposition. We also found mPTP opening was significantly attenuated in wt mice after removing mitochondrial matrix, while that in db/db mice remained active. In addition, we observed that AA could directly activate mPTP in inside-out mode, independent of matrix calcium. In conclusion, we for the first time provided a physiological evidence of mPTP opening in lipid deposition, which could be directly induced by AA without Ca2+ and can be inhibited by cyclosporine A. As a result, it led to mitochondria morphology and function transformation. This might provide insights into potential therapeutic target for future treatment of mitochondrial liver disease.
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Affiliation(s)
- Yuan Li
- Institute of Molecular Medicine, Peking University, Beijing, China.
| | - Jing Wu
- Institute of Molecular Medicine, Peking University, Beijing, China
| | - Min Yang
- Institute of Molecular Medicine, Peking University, Beijing, China
| | - Lisi Wei
- National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Hongkun Wu
- Institute of Molecular Medicine, Peking University, Beijing, China
| | - Qinyi Wang
- Institute of Molecular Medicine, Peking University, Beijing, China
| | - Hui Shi
- Institute of Molecular Medicine, Peking University, Beijing, China
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Nath S. A Novel Conceptual Model for the Dual Role of FOF1-ATP Synthase in Cell Life and Cell Death. Biomol Concepts 2020; 11:143-152. [PMID: 32827389 DOI: 10.1515/bmc-2020-0014] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 07/22/2020] [Indexed: 12/31/2022] Open
Abstract
The mitochondrial permeability transition (MPT) has been one of the longstanding enigmas in biology. Its cause is currently at the center of an extensive scientific debate, and several hypotheses on its molecular nature have been put forward. The present view holds that the transition arises from the opening of a high-conductance channel in the energy-transducing membrane, the permeability transition pore (PTP), also called the mitochondrial megachannel or the multiconductance channel (MMC). Here, the novel hypothesis is proposed that the aqueous access channels at the interface of the c-ring and the a-subunit of FO in the FOF1-ATP synthase are repurposed during induction of apoptosis and constitute the elusive PTP/ MMC. A unifying principle based on regulation by local potentials is advanced to rationalize the action of the myriad structurally and chemically diverse inducers and inhibitors of PTP/MMC. Experimental evidence in favor of the hypothesis and its differences from current models of PTP/MMC are summarized. The hypothesis explains in considerable detail how the binding of Ca2+ to a β-catalytic site (site 3) in the F1 portion of ATP synthase triggers the opening of the PTP/MMC. It is also shown to connect to longstanding proposals within Nath's torsional mechanism of energy transduction and ATP synthesis as to how the binding of MgADP to site 3 does not induce PTP/MMC, but instead catalyzes physiological ATP synthesis in cell life. In the author's knowledge, this is the first model that explains how Ca2+ transforms the FOF1-ATP synthase from an exquisite energy-conserving enzyme in cell life into an energy-dissipating structure that promotes cell death. This has major implications for basic as well as for clinical research, such as for the development of drugs that target the MPT, given the established role of PTP/MMC dysregulation in cancer, ischemia, cardiac hypertrophy, and various neurodegenerative diseases.
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Affiliation(s)
- Sunil Nath
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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9
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Mishra PK, Adameova A, Hill JA, Baines CP, Kang PM, Downey JM, Narula J, Takahashi M, Abbate A, Piristine HC, Kar S, Su S, Higa JK, Kawasaki NK, Matsui T. Guidelines for evaluating myocardial cell death. Am J Physiol Heart Circ Physiol 2019; 317:H891-H922. [PMID: 31418596 DOI: 10.1152/ajpheart.00259.2019] [Citation(s) in RCA: 135] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Cell death is a fundamental process in cardiac pathologies. Recent studies have revealed multiple forms of cell death, and several of them have been demonstrated to underlie adverse cardiac remodeling and heart failure. With the expansion in the area of myocardial cell death and increasing concerns over rigor and reproducibility, it is important and timely to set a guideline for the best practices of evaluating myocardial cell death. There are six major forms of regulated cell death observed in cardiac pathologies, namely apoptosis, necroptosis, mitochondrial-mediated necrosis, pyroptosis, ferroptosis, and autophagic cell death. In this article, we describe the best methods to identify, measure, and evaluate these modes of myocardial cell death. In addition, we discuss the limitations of currently practiced myocardial cell death mechanisms.
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Affiliation(s)
- Paras K Mishra
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska
| | - Adriana Adameova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University of Bratislava, Bratislava, Slovakia
| | - Joseph A Hill
- Departments of Medicine (Cardiology) and Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Christopher P Baines
- Department of Biomedical Sciences, Dalton Cardiovascular Research Center, University of Missouri-Columbia, Columbia, Missouri
| | - Peter M Kang
- Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - James M Downey
- Department of Physiology and Cell Biology, College of Medicine, University of South Alabama, Mobile, Alabama
| | - Jagat Narula
- Mount Sinai Heart, Icahn School of Medicine at Mount Sinai Hospital, New York, New York
| | - Masafumi Takahashi
- Division of Inflammation Research, Center of Molecular Medicine, Jichi Medical University, Tochigi, Japan
| | - Antonio Abbate
- Virginia Commonwealth University, Pauley Heart Center, Richmond, Virginia
| | - Hande C Piristine
- Department of Medicine (Cardiology), University of Texas Southwestern Medical Center, Dallas, Texas
| | - Sumit Kar
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska
| | - Shi Su
- Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Jason K Higa
- Department of Anatomy, Biochemistry, and Physiology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, Hawaii
| | - Nicholas K Kawasaki
- Department of Anatomy, Biochemistry, and Physiology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, Hawaii
| | - Takashi Matsui
- Department of Anatomy, Biochemistry, and Physiology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, Hawaii
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Baines CP, Gutiérrez-Aguilar M. The still uncertain identity of the channel-forming unit(s) of the mitochondrial permeability transition pore. Cell Calcium 2018; 73:121-130. [PMID: 29793100 PMCID: PMC5993635 DOI: 10.1016/j.ceca.2018.05.003] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 05/07/2018] [Accepted: 05/12/2018] [Indexed: 10/16/2022]
Abstract
Mitochondria from different organisms can undergo a sudden process of inner membrane unselective leakiness to molecules known as the mitochondrial permeability transition (MPT). This process has been studied for nearly four decades and several proteins have been claimed to constitute, or at least regulate the usually inactive pore responsible for this transition. However, no protein candidate proposed as the actual pore-forming unit has passed rigorous gain- or loss-of-function genetic tests. Here we review evidence for -and against- putative channel-forming components of the MPT pore. We conclude that the structure of the MPT pore still remains largely undefined and suggest that future studies should follow established technical considerations to unambiguously consolidate the channel forming constituent(s) of the MPT pore.
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Affiliation(s)
- Christopher P Baines
- Dalton Cardiovascular Research Center, University of Missouri-Columbia, Columbia, MO 65211, USA; Department of Biomedical Sciences, University of Missouri-Columbia, Columbia, MO 65211, USA; Department of Medical Pharmacology and Physiology, University of Missouri-Columbia, Columbia, MO 65211, USA.
| | - Manuel Gutiérrez-Aguilar
- Departamento de Bioquímica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510 Ciudad de México, Mexico.
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Biasutto L, Azzolini M, Szabò I, Zoratti M. The mitochondrial permeability transition pore in AD 2016: An update. BIOCHIMICA ET BIOPHYSICA ACTA 2016; 1863:2515-30. [PMID: 26902508 DOI: 10.1016/j.bbamcr.2016.02.012] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 02/04/2016] [Accepted: 02/05/2016] [Indexed: 12/13/2022]
Abstract
Over the past 30years the mitochondrial permeability transition - the permeabilization of the inner mitochondrial membrane due to the opening of a wide pore - has progressed from being considered a curious artifact induced in isolated mitochondria by Ca(2+) and phosphate to a key cell-death-inducing process in several major pathologies. Its relevance is by now universally acknowledged and a pharmacology targeting the phenomenon is being developed. The molecular nature of the pore remains to this day uncertain, but progress has recently been made with the identification of the FOF1 ATP synthase as the probable proteic substrate. Researchers sharing this conviction are however divided into two camps: these believing that only the ATP synthase dimers or oligomers can form the pore, presumably in the contact region between monomers, and those who consider that the ring-forming c subunits in the FO sector actually constitute the walls of the pore. The latest development is the emergence of a new candidate: Spastic Paraplegia 7 (SPG7), a mitochondrial AAA-type membrane protease which forms a 6-stave barrel. This review summarizes recent developments of research on the pathophysiological relevance and on the molecular nature of the mitochondrial permeability transition pore. This article is part of a Special Issue entitled: Mitochondrial Channels edited by Pierre Sonveaux, Pierre Maechler and Jean-Claude Martinou.
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Affiliation(s)
- Lucia Biasutto
- CNR Neuroscience Institute, Viale G. Colombo 3, 35121 Padova, Italy; University of Padova, Department of Biomedical Sciences, Viale G. Colombo 3, 35121 Padova, Italy
| | - Michele Azzolini
- CNR Neuroscience Institute, Viale G. Colombo 3, 35121 Padova, Italy; University of Padova, Department of Biomedical Sciences, Viale G. Colombo 3, 35121 Padova, Italy
| | - Ildikò Szabò
- CNR Neuroscience Institute, Viale G. Colombo 3, 35121 Padova, Italy; University of Padova, Department of Biology, Viale G. Colombo 3, 35121 Padova, Italy
| | - Mario Zoratti
- CNR Neuroscience Institute, Viale G. Colombo 3, 35121 Padova, Italy; University of Padova, Department of Biomedical Sciences, Viale G. Colombo 3, 35121 Padova, Italy.
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Novoderezhkina EA, Zhivotovsky BD, Gogvadze VG. Induction of unspecific permeabilization of mitochondrial membrane and its role in cell death. Mol Biol 2016. [DOI: 10.1134/s0026893316010167] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Santo-Domingo J, Wiederkehr A, De Marchi U. Modulation of the matrix redox signaling by mitochondrial Ca 2+. World J Biol Chem 2015; 6:310-323. [PMID: 26629314 PMCID: PMC4657127 DOI: 10.4331/wjbc.v6.i4.310] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 09/04/2015] [Accepted: 10/13/2015] [Indexed: 02/05/2023] Open
Abstract
Mitochondria sense, shape and integrate signals, and thus function as central players in cellular signal transduction. Ca2+ waves and redox reactions are two such intracellular signals modulated by mitochondria. Mitochondrial Ca2+ transport is of utmost physio-pathological relevance with a strong impact on metabolism and cell fate. Despite its importance, the molecular nature of the proteins involved in mitochondrial Ca2+ transport has been revealed only recently. Mitochondrial Ca2+ promotes energy metabolism through the activation of matrix dehydrogenases and down-stream stimulation of the respiratory chain. These changes also alter the mitochondrial NAD(P)H/NAD(P)+ ratio, but at the same time will increase reactive oxygen species (ROS) production. Reducing equivalents and ROS are having opposite effects on the mitochondrial redox state, which are hard to dissect. With the recent development of genetically encoded mitochondrial-targeted redox-sensitive sensors, real-time monitoring of matrix thiol redox dynamics has become possible. The discoveries of the molecular nature of mitochondrial transporters of Ca2+ combined with the utilization of the novel redox sensors is shedding light on the complex relation between mitochondrial Ca2+ and redox signals and their impact on cell function. In this review, we describe mitochondrial Ca2+ handling, focusing on a number of newly identified proteins involved in mitochondrial Ca2+ uptake and release. We further discuss our recent findings, revealing how mitochondrial Ca2+ influences the matrix redox state. As a result, mitochondrial Ca2+ is able to modulate the many mitochondrial redox-regulated processes linked to normal physiology and disease.
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Chinopoulos C, Szabadkai G. What Makes You Can also Break You, Part III: Mitochondrial Permeability Transition Pore Formation by an Uncoupling Channel within the C-Subunit Ring of the F1FO ATP Synthase? Front Oncol 2014; 4:235. [PMID: 25232534 PMCID: PMC4153043 DOI: 10.3389/fonc.2014.00235] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 08/11/2014] [Indexed: 11/13/2022] Open
Affiliation(s)
| | - Gyorgy Szabadkai
- Department of Cell and Developmental Biology, Consortium for Mitochondrial Research, University College London , London , UK ; Department of Biomedical Sciences, University of Padua , Padua , Italy
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15
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Halestrap AP, Richardson AP. The mitochondrial permeability transition: a current perspective on its identity and role in ischaemia/reperfusion injury. J Mol Cell Cardiol 2014; 78:129-41. [PMID: 25179911 DOI: 10.1016/j.yjmcc.2014.08.018] [Citation(s) in RCA: 310] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 08/21/2014] [Accepted: 08/24/2014] [Indexed: 12/29/2022]
Abstract
The mitochondrial permeability transition pore (MPTP) is a non-specific pore that opens in the inner mitochondrial membrane (IMM) when matrix [Ca(2+)] is high, especially when accompanied by oxidative stress, high [Pi] and adenine nucleotide depletion. Such conditions occur during ischaemia and subsequent reperfusion, when MPTP opening is known to occur and cause irreversible damage to the heart. Matrix cyclophilin D facilitates MPTP opening and is the target of its inhibition by cyclosporin A that is cardioprotective. Less certainty exists over the composition of the pore itself, with structural and/or regulatory roles proposed for the adenine nucleotide translocase, the phosphate carrier and the FoF1 ATP synthase. Here we critically review the supporting data for the role of each and suggest that they may interact with each other through their bound cardiolipin to form the ATP synthasome. We propose that under conditions favouring MPTP opening, calcium-triggered conformational changes in these proteins may perturb the interface between them generating the pore. Proteins associated with the outer mitochondrial membrane (OMM), such as members of the Bcl-2 family and hexokinase (HK), whilst not directly involved in pore formation, may regulate MPTP opening through interactions between OMM and IMM proteins at "contact sites". Recent evidence suggests that cardioprotective protocols such as preconditioning inhibit MPTP opening at reperfusion by preventing the loss of mitochondrial bound HK2 that stabilises these contact sites. Contact site breakage both sensitises the MPTP to [Ca(2+)] and facilitates cytochrome c loss from the intermembrane space leading to greater ROS production and further MPTP opening. This article is part of a Special Issue entitled "Mitochondria: From Basic Mitochondrial Biology to Cardiovascular Disease".
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Affiliation(s)
- Andrew P Halestrap
- School of Biochemistry and Bristol CardioVascular, University of Bristol, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK.
| | - Andrew P Richardson
- School of Biochemistry and Bristol CardioVascular, University of Bristol, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
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16
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Halestrap AP. The C Ring of the F1Fo ATP Synthase Forms the Mitochondrial Permeability Transition Pore: A Critical Appraisal. Front Oncol 2014; 4:234. [PMID: 25202683 PMCID: PMC4142482 DOI: 10.3389/fonc.2014.00234] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 08/11/2014] [Indexed: 11/13/2022] Open
Affiliation(s)
- Andrew P Halestrap
- School of Biochemistry and Bristol CardioVascular, University of Bristol , Bristol , UK
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17
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Gutiérrez-Aguilar M, Douglas DL, Gibson AK, Domeier TL, Molkentin JD, Baines CP. Genetic manipulation of the cardiac mitochondrial phosphate carrier does not affect permeability transition. J Mol Cell Cardiol 2014; 72:316-25. [PMID: 24768964 PMCID: PMC4080311 DOI: 10.1016/j.yjmcc.2014.04.008] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 04/10/2014] [Accepted: 04/13/2014] [Indexed: 02/07/2023]
Abstract
The Mitochondrial Permeability Transition (MPT) pore is a voltage-sensitive unselective channel known to instigate necrotic cell death during cardiac disease. Recent models suggest that the isomerase cyclophilin D (CypD) regulates the MPT pore by binding to either the F0F1-ATP synthase lateral stalk or the mitochondrial phosphate carrier (PiC). Here we confirm that CypD, through its N-terminus, can directly bind PiC. We then generated cardiac-specific mouse strains overexpressing or with decreased levels of mitochondrial PiC to assess the functionality of such interaction. While PiC overexpression had no observable pathologic phenotype, PiC knockdown resulted in cardiac hypertrophy along with decreased ATP levels. Mitochondria isolated from the hearts of these mouse lines and their respective non-transgenic controls had no divergent phenotype in terms of oxygen consumption and Ca(2+)-induced MPT, as assessed by swelling and Ca(2+)-retention measurements. These results provide genetic evidence indicating that the mitochondrial PiC is not a critical component of the MPT pore.
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Affiliation(s)
| | - Diana L Douglas
- Dalton Cardiovascular Research Center, University of Missouri-Columbia, Columbia, MO 65211, USA
| | - Anne K Gibson
- Department of Medical Pharmacology and Physiology, University of Missouri-Columbia, Columbia, MO 65211, USA
| | - Timothy L Domeier
- Department of Medical Pharmacology and Physiology, University of Missouri-Columbia, Columbia, MO 65211, USA
| | - Jeffery D Molkentin
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA; Howard Hughes Medical Institute, Cincinnati, OH 45229, USA
| | - Christopher P Baines
- Dalton Cardiovascular Research Center, University of Missouri-Columbia, Columbia, MO 65211, USA; Department of Biomedical Sciences, University of Missouri-Columbia, Columbia, MO 65211, USA; Department of Medical Pharmacology and Physiology, University of Missouri-Columbia, Columbia, MO 65211, USA.
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De Marchi U, Santo-Domingo J, Castelbou C, Sekler I, Wiederkehr A, Demaurex N. NCLX protein, but not LETM1, mediates mitochondrial Ca2+ extrusion, thereby limiting Ca2+-induced NAD(P)H production and modulating matrix redox state. J Biol Chem 2014; 289:20377-85. [PMID: 24898248 DOI: 10.1074/jbc.m113.540898] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Mitochondria capture and subsequently release Ca(2+) ions, thereby sensing and shaping cellular Ca(2+) signals. The Ca(2+) uniporter MCU mediates Ca(2+) uptake, whereas NCLX (mitochondrial Na/Ca exchanger) and LETM1 (leucine zipper-EF-hand-containing transmembrane protein 1) were proposed to exchange Ca(2+) against Na(+) or H(+), respectively. Here we study the role of these ion exchangers in mitochondrial Ca(2+) extrusion and in Ca(2+)-metabolic coupling. Both NCLX and LETM1 proteins were expressed in HeLa cells mitochondria. The rate of mitochondrial Ca(2+) efflux, measured with a genetically encoded indicator during agonist stimulations, increased with the amplitude of mitochondrial Ca(2+) ([Ca(2+)]mt) elevations. NCLX overexpression enhanced the rates of Ca(2+) efflux, whereas increasing LETM1 levels had no impact on Ca(2+) extrusion. The fluorescence of the redox-sensitive probe roGFP increased during [Ca(2+)]mt elevations, indicating a net reduction of the matrix. This redox response was abolished by NCLX overexpression and restored by the Na(+)/Ca(2+) exchanger inhibitor CGP37157. The [Ca(2+)]mt elevations were associated with increases in the autofluorescence of NAD(P)H, whose amplitude was strongly reduced by NCLX overexpression, an effect reverted by Na(+)/Ca(2+) exchange inhibition. We conclude that NCLX, but not LETM1, mediates Ca(2+) extrusion from mitochondria. By controlling the duration of matrix Ca(2+) elevations, NCLX contributes to the regulation of NAD(P)H production and to the conversion of Ca(2+) signals into redox changes.
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Affiliation(s)
- Umberto De Marchi
- From the Mitochondrial Function, Nestlé Institute of Health Sciences, EPFL Innovation Park, Building G, CH-1015 Lausanne, Switzerland, the Department of Cell Physiology and Metabolism, University of Geneva, Rue Michel-Servet, 1, CH-1211 Genève, Switzerland, and
| | - Jaime Santo-Domingo
- From the Mitochondrial Function, Nestlé Institute of Health Sciences, EPFL Innovation Park, Building G, CH-1015 Lausanne, Switzerland, the Department of Cell Physiology and Metabolism, University of Geneva, Rue Michel-Servet, 1, CH-1211 Genève, Switzerland, and
| | - Cyril Castelbou
- the Department of Cell Physiology and Metabolism, University of Geneva, Rue Michel-Servet, 1, CH-1211 Genève, Switzerland, and
| | - Israel Sekler
- the Department of Physiology, Ben-Gurion University of Negev, Beer-Sheva 84105, Israel
| | - Andreas Wiederkehr
- From the Mitochondrial Function, Nestlé Institute of Health Sciences, EPFL Innovation Park, Building G, CH-1015 Lausanne, Switzerland
| | - Nicolas Demaurex
- the Department of Cell Physiology and Metabolism, University of Geneva, Rue Michel-Servet, 1, CH-1211 Genève, Switzerland, and
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Abstract
The field of mitochondrial ion channels has recently seen substantial progress, including the molecular identification of some of the channels. An integrative approach using genetics, electrophysiology, pharmacology, and cell biology to clarify the roles of these channels has thus become possible. It is by now clear that many of these channels are important for energy supply by the mitochondria and have a major impact on the fate of the entire cell as well. The purpose of this review is to provide an up-to-date overview of the electrophysiological properties, molecular identity, and pathophysiological functions of the mitochondrial ion channels studied so far and to highlight possible therapeutic perspectives based on current information.
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20
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Hypothesis of lipid-phase-continuity proton transfer for aerobic ATP synthesis. J Cereb Blood Flow Metab 2013; 33:1838-42. [PMID: 24084698 PMCID: PMC3851912 DOI: 10.1038/jcbfm.2013.175] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 09/09/2013] [Accepted: 09/12/2013] [Indexed: 12/12/2022]
Abstract
The basic processes harvesting chemical energy for life are driven by proton (H(+)) movements. These are accomplished by the mitochondrial redox complex V, integral membrane supramolecular aggregates, whose structure has recently been described by advanced studies. These did not identify classical aqueous pores. It was proposed that H(+) transfer for oxidative phosphorylation (OXPHOS) does not occur between aqueous sources and sinks, where an energy barrier would be insurmountable. This suggests a novel hypothesis for the proton transfer. A lipid-phase-continuity H(+) transfer is proposed in which H(+) are always bound to phospholipid heads and cardiolipin, according to Mitchell's hypothesis of asymmetric vectorial H(+) diffusion. A phase separation is proposed among the proton flow, following an intramembrane pathway, and the ATP synthesis, occurring in the aqueous phase. This view reminiscent of Grotthus mechanism would better account for the distance among the Fo and F1 moieties of FoF1-ATP synthase, for its mechanical coupling, as well as the necessity of a lipid membrane. A unique active role for lipids in the evolution of life can be envisaged. Interestingly, this view would also be consistent with the evidence of an OXPHOS outside mitochondria also found in non-vesicular membranes, housing the redox complexes.
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Abstract
Mitochondria are implicated in many important cellular functions covering the whole life cycle from mitochondrial biogenesis to cell death. Mitochondrial homeostasis is tightly regulated, and mitochondrial dysfunction is frequently associated with severe human pathologies (eg, cardiovascular diseases, cancer, and neurodegeneration). The permeability transition pore (PTP) is an unselective voltage-dependent mitochondrial channel. Despite the extensive use of electrophysiology, biochemistry, pharmacology, and genetic invalidation in mice, the molecular identity of PTP is still unknown. Nevertheless, PTP is central to mitochondrial vital functions and can play a lethal role in many pathophysiological conditions. This review recapitulates the current knowledge of the various modes of conductance of the PTP channel and discusses their implication in the physiological roles of PTP and their regulation. Based on its involvement in normal physiology and human pathology, a better understanding of this channel and its roles remains a major goal for basic scientists and clinicians.
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Affiliation(s)
- Catherine Brenner
- INSERM UMR-S 769, LabEx LERMIT, Université de Paris-Sud, 5, Rue JB Clément, 92296 Châtenay-Malabry, France.
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22
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Abstract
SIGNIFICANCE Plants produce many small molecules with biomedical potential. Their absorption from foods, metabolism, their effects on physiological and pathological processes, and the mechanisms of action are intensely investigated. Many are known to affect multiple cellular functions. Mitochondria are coming to be recognized as a major target for these compounds, especially redox-active ones, but the mechanisms involved still need clarification. At the same time, frontline research is uncovering the importance of processes involving these organelles for the cell and for an array of physiological and pathological processes. We review the major functions and possible dysfunctions of mitochondria, identify signaling pathways through which plant-derived molecules have an impact, and show how this may be relevant for major pathologies. RECENT ADVANCES Antioxidant, protective effects may arise as a reaction to a low-level pro-oxidant activity, largely taking place at mitochondria. Some plant-derived molecules can activate AMP-dependent kinase, with a consequent upregulation of mitochondrial biogenesis and a potential favorable impact on aging, pathologies like diabetes and neurodegeneration, and on ischemic damage. CRITICAL ISSUES The extrapolation of in vitro results and the verification of paradigms in vivo is a key issue for current research on both plant-derived compounds and mitochondria. The low bioavailability of many of these molecules poses a problem for both the study of their activities and their utilization. FUTURE DIRECTIONS The further clarification of the role of mitochondria in the activities of plant dietary compounds and their metabolites, mitochondrial targeting, the development of analogs and pro-drugs are all topics for promising research.
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Affiliation(s)
- Lucia Biasutto
- CNR Institute of Neuroscience, Department of Experimental Biomedical Sciences, University of Padova, Padova, Italy
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Reactive oxygen species and permeability transition pore in rat liver and kidney mitoplasts. J Bioenerg Biomembr 2011; 43:709-15. [PMID: 21964737 DOI: 10.1007/s10863-011-9384-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Accepted: 08/23/2011] [Indexed: 10/17/2022]
Abstract
Mitochondrial permeability transition is typically characterized by Ca(2+) and oxidative stress-induced opening of a nonselective proteinaceous membrane pore sensitive to cyclosporin A, known as the permeability transition pore (PTP). Data from our laboratory provide evidence that the PTP is formed when inner membrane proteins aggregate as a result of disulfide cross-linking caused by thiol oxidation. Here we compared the redox properties between PTP in intact mitochondria and mitoplasts. The rat liver mitoplasts retained less than 5% and 10% of the original outer membrane markers monoamine oxidase and VDAC, respectively. Kidney mitoplasts also showed a partial depletion of hexokinase. In line with the redox nature of the PTP, mitoplasts that were more susceptible to PTP opening than intact mitochondria showed higher rates of H(2)O(2) generation and decreased matrix NADPH-dependent antioxidant activity. Mitoplast PTP was also sensitive to the permeability transition inducer tert-butyl hydroperoxide and to the inhibitors cyclosporin A, EGTA, ADP, dithiothreitol and catalase. Taken together, these data indicate that, in mitoplasts, PTP exhibits redox regulatory characteristics similar to those described for intact mitochondria.
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24
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Gouriou Y, Demaurex N, Bijlenga P, De Marchi U. Mitochondrial calcium handling during ischemia-induced cell death in neurons. Biochimie 2011; 93:2060-7. [PMID: 21846486 DOI: 10.1016/j.biochi.2011.08.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Accepted: 08/03/2011] [Indexed: 12/18/2022]
Abstract
Mitochondria sense and shape cytosolic Ca(2+) signals by taking up and subsequently releasing Ca(2+) ions during physiological and pathological Ca(2+) elevations. Sustained elevations in the mitochondrial matrix Ca(2+) concentration are increasingly recognized as a defining feature of the intracellular cascade of lethal events that occur in neurons during cerebral ischemia. Here, we review the recently identified transport proteins that mediate the fluxes of Ca(2+) across mitochondria and discuss the implication of the permeability transition pore in decoding the abnormally sustained mitochondrial Ca(2+) elevations that occur during cerebral ischemia.
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Affiliation(s)
- Yves Gouriou
- Department of Cell Physiology and Metabolism, University of Geneva, rue Michel-Servet 1, Genève, Switzerland
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25
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Mitochondrial Unselective Channels throughout the eukaryotic domain. Mitochondrion 2011; 11:382-90. [DOI: 10.1016/j.mito.2011.02.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 02/16/2011] [Accepted: 02/25/2011] [Indexed: 02/03/2023]
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26
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De Marchi U, Checchetto V, Zanetti M, Teardo E, Soccio M, Formentin E, Giacometti GM, Pastore D, Zoratti M, Szabò I. ATP-sensitive cation-channel in wheat (Triticum durum Desf.): identification and characterization of a plant mitochondrial channel by patch-clamp. Cell Physiol Biochem 2011; 26:975-82. [PMID: 21220928 DOI: 10.1159/000324010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/04/2010] [Indexed: 11/19/2022] Open
Abstract
Indirect evidence points to the presence of K(+) channels in plant mitochondria. In the present study, we report the results of the first patch clamp experiments on plant mitochondria. Single-channel recordings in 150 mM potassium gluconate have allowed the biophysical characterization of a channel with a conductance of 150 pS in the inner mitochondrial membrane of mitoplasts obtained from wheat (Triticum durum Desf.). The channel displayed sharp voltage sensitivity, permeability to potassium and cation selectivity. ATP in the mM concentration range completely abolished the activity. We discuss the possible molecular identity of the channel and its possible role in the defence mechanisms against oxidative stress in plants.
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Affiliation(s)
- Umberto De Marchi
- Department of Experimental Biomedical Sciences, CNR Institute of Neuroscience, University of Padova, Padova, Italy.
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Biasutto L, Dong LF, Zoratti M, Neuzil J. Mitochondrially targeted anti-cancer agents. Mitochondrion 2010; 10:670-81. [PMID: 20601192 DOI: 10.1016/j.mito.2010.06.004] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2010] [Revised: 06/20/2010] [Accepted: 06/23/2010] [Indexed: 01/12/2023]
Abstract
Cancer is an ever-increasing problem that is yet to be harnessed. Frequent mutations make this pathology very variable and, consequently, a considerable challenge. Intriguingly, mitochondria have recently emerged as novel targets for cancer therapy. A group of agents with anti-cancer activity that induce apoptosis by way of mitochondrial destabilisation, termed mitocans, have been a recent focus of research. Of these compounds, many are hydrophobic agents that associate with various sub-cellular organelles. Clearly, modification of such structures with mitochondria-targeting moieties, for example tagging them with lipophilic cations, would be expected to enhance their activity. This may be accomplished by the addition of triphenylphosphonium groups that direct such compounds to mitochondria, enhancing their activity. In this paper, we will review agents that possess anti-cancer activity by way of destabilizing mitochondria and their possible targets. We propose that mitochondrial targeting, in particular where the agent associates directly with the target, results in more specific and efficient anti-cancer drugs of potential high clinical relevance.
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Affiliation(s)
- Lucia Biasutto
- CNR Institute of Neuroscience and Dept. of Experimental Biomedical Sciences, University of Padova, Padova, Italy
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